VOLUME 1, JUNE 2020
Journal of Organic Biochemistry at St. Andrew’s Review articles researched and written by Upper School students.
A Note From the Editor
W
elcome to the inaugural issue of the Journal of Organic Biochemistry at St. Andrew’s (JOBSA). Each of the following review articles was researched and written by Upper School students as part of their culminating project in Fundamentals of Organic
Biochemistry, a rigorous senior year course for students interested in learning more about the chemical sciences. During the winter and spring, students learn to read current research articles in biochemistry. In April, students present an indepth analysis of a recent journal article of their choice. This final project requires each student to write their own review style article, synthesized from the information they find in multiple professional publications. Each project is then anonymously reviewed by their peers, simulating the publication process found in science today. A selection of the top articles have been collected here. We hope you enjoy the following works and are similarly inspired to explore the way chemistry impacts our world. Regards, Mr. William Ferriby
Table of Contents The Chemistry of Vaping Products and Cigarettes: A Comprehensive Review Nick Tsintolas
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Chrysin’s Antioxidant Effects on the Nervous System Show Its Potential Therapeutic Significance Anyi Li The Impact of Chocolate and Other Cocoa Products on Human Health Amanda Newcombe
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A Brief Review of the Pharmacology of Psilocybin Cameron Behram
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Artificial Food Coloring and its Effects on Human Health Theo Camille Burden
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Acrylamide: A Review of Its Formation and Health Effects Josh Lobsenz
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An Analysis of the Biochemical Mechanisms of Stress in the Brain Charlotte Wenk
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The Chemistry of Vaping Products and Cigarettes: A Comprehensive Review Nick Tsintolas Abstract: The recent popularization of ecigarette products as a safer alternative to smoking has prompted extensive scientific research into the kinds and extent of chemicals it produces in comparison to a traditional cigarette. This article serves as a review of the current knowledge surrounding the chemistry of vape and cigarette emissions and as a call for further research. Introduction to Vapes and Cigarettes: E-cigarettes, or vapes, have entered the mainstream and revolutionized the “smoking” experience. An understanding of these products is essential when discussing the chemicals they give off. Vapes work by heating a liquid cartridge containing nicotine and other chemicals, aerosolizing the mixture.1 See Figure 1 below:
Figure 1: A breakdown of the components of a traditional e- cigarette. Note the heating coil, nicotine cartridge, and vaporizing chamber as the producers of the aerosolized mixture.2 These chemicals, called “base compounds,” include propylene glycol and vegetable glycerin, which initially on their own are not dangerous. When heated, they become the toxic chemicals acrolein, formaldehyde, and acid aldehyde.3 When 1
analyzing the chemicals produced by vapes, it is important to consider their origin. Many vaping injuries and illnesses result from the use of devices tampered with in the black market or modified by their users. This is especially pertinent to vapes containing THC, the active ingredient in marijuana. These alterations worsen the effect of vapes and can confound proper experimentation into their chemical production.4 For cigarettes, the tobacco and other chemicals follow a combustion reaction.1 While there is a difference in how smokers and vapers are exposed to these harmful chemicals and the extent of the exposure, a vast majority of the chemicals are the same.3 The primary chemical both products contain is nicotine, an addictive substance that causes stress with withdrawal and brings a sense of relaxation with use.5 Nicotine can also raise blood pressure, increase adrenaline levels, and increase the risk for a heart attack.4 Vaping can cause seizures and serious lung damage after just a year of use. The chemicals in e-cigarettes can also hamper brain development in children. The documented illnesses and conditions associated with smoking are lung cancer, breast cancer, shortness of breath, and heart disease, all of which develop after years of exposure to these chemicals.5 Discussion of Scientific Research: Initial studies into the chemical output of ecigarettes by the FDA revealed a toxic compound in antifreeze and carcinogenic tobacco-related compounds present in ecigarettes advertised as “tobacco free”. Significant levels of other carcinogens like formaldehyde and benzene were detected in these vaping products. Levels of acrolein, a chemical known to damage DNA, increased in the saliva of five adults after a 15-minute vaping session. Acrolein’s DNA alteration potential establishes it as an additional carcinogen present in vapes.5 Juul, a popular e-cigarette manufacturer, has made natural
nicotine more neutral and thus less irritating to the throat, and as a result has increased the nicotine content in their products, which exacerbates its addictive qualities.3 Following these initial discoveries about the chemicals in vapes and cigarettes, research teams in 2016 including Jennifer Margham, et al and in 2020 including James Nichol, et al studied the chemical composition of e-cigarettes and published their findings in Chemical Research in Toxicology. The team including Nichol, et al, advanced the work of Margham, et al and included many of the same researchers.6 Margham, et al used the Ky3R4F Kentucky Reference Cigarette as the cigarette reference and the Vype ePen as the e-cigarette reference, both of which are legitimate, untampered products. A smoking machine was used to simulate use.6
out of liquid, so the experimenters recorded results in increments of 100 puffs. Likewise, the cigarette puff rate and volume in the study were also standardized; the Ky3R4F cigarette lasts between 10-15 puffs, so researchers recorded emissions on a percigarette basis. Researchers also measured relevant chemical levels in their laboratory air as a control. All samples were analyzed for their chemical emissions.6 Many of the chemical emissions in the study were in trace quantities below the limit of detection (LOD) and/or the limit of quantification (LOQ). With the goal of obtaining a percentage difference between the ePen and Ky3R4F emissions, researchers used Equation (1) to obtain an emission value when one product’s data was less than the LOD: (1) !"#!$#"%&' ("#$& =
)&*+)%&' ("#$& 2
In order to report levels greater than the LOD but less than the LOQ, (when data is detectable but not fully useful) researchers used Equation (2): (2) !"#!$#"%&' ("#$& = )&*+)%&' ,-. + (
Figure 2: A smoking machine similar to the one used in the study. The barrel, pictured here, is attached to a ventilator that breathes in and out, simulating taking a puff from a cigarette or vape.7 The vape puff rate and volume were standardized throughout the study. The Vype ePen provides 200 puffs before it runs
Compound Formaldehyde Acetaldehyde Acrolein Glycerol Propylene Glycol Nicotine Acetone
)&*+)%&' ,-/ − )&*+)%&' ,-. 2
)
Vape and cigarette levels below both the LOD and LOQ, were omitted from percentage difference calculations.6 Table 1 summarizes the e-cigarette emission levels of the chemicals discussed earlier in this article review in comparison to cigarette emissions. These are only a handful of the over 150 toxicants analyzed.6
Table 1: Results from Margham, et al.6 Emission Results 98.6-99.9% less emissions in vapes; for vape emissions, half were from air, half were from ePen 98.6-99.9% less emissions in vapes; for vape emissions, half were from in air, half were from ePen 98.6-99.9% less emissions in vapes; all emissions exclusively from ePen Higher emission levels than cigarettes due to its role in heating the liquid Higher emission levels than cigarettes due to its role in heating the liquid 97% less emissions than cigarettes 98.6-99.9% less emissions in vapes; for vapes, more present in air than from ePen
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Compound Formaldehyde Acetaldehyde Acrolein Glycerol Propylene Glycol Nicotine Acetone
Table 2: Results from Nichols, et al.3 Emission Results Less emissions in vapes; a non-significant difference was detected between IS1.0(TT) and ePen levels Less emissions in vapes; levels no hirer from IS1.0(TT) than from the air Less emissions in vapes; levels no hirer from IS1.0(TT) than from the air Higher emission levels from IS1.0(TT) than cigarettes and ePen, used in the liquid heating process Higher emission levels from IS1.0(TT) than cigarettes and ePen, used in the liquid heating process 97% less emissions than cigarettes; similar emissions between IS1.0(TT) and ePen Less emissions in vapes (Further details not extensively reported)
Overall, the ePen was shown to have fewer chemical emissions in its aerosol than cigarettes, with, on average, between 82-99% lower per-puff emission level than the traditional cigarette. The authors of this article suggested their findings support the claim that e-cigarettes are a “less harmful alternative” to traditional cigarettes, but they remained cautious of the impact of these toxicants, even at decreased levels.6 They used the 1RgF Kentucky Reference Cigarette as the cigarette reference, IS1.0(TT) as an e- cigarette reference, previous data on the Vype ePen, and a control of laboratory air. A smoking machine was also used to simulate use. Similar procedures as the previous study were used for emission analysis. Table 2 summarizes the findings of Nichol, et al.3
1 Rodriguez,
In general, Nichol, et al concurred with the previous study to show that e-cigarettes had significantly lower toxicant levels than cigarettes. These researchers cite the need to test the toxicology of the chemicals at the levels they are found in e-cigarette aerosols.3 Conclusions and Further Research: While extensive research has identified the similarities between of the chemicals produces by vapes and cigarettes, this knowledge is not exhaustive. Given that cancers take years to develop and vaping products are new to the market, decades must pass to allow the longterm studies required to fully understand the effects of vaping to be conducted. More research is necessary to confirm and supplement what is known about the chemistry of vaping and cigarettes, especially its impact on the body.
Carmen Heredia. "Cigarettes Vs. Vaping: That's the 'Wrong Comparison,' Says Inhalation Researcher." Kaiser Health News, Kaiser Family Foundation, 4 Nov. 2019, khn.org/news/cigarettes-vs-vaping-thatsthe-wrong-comparison-says-inhalation-researcher/. Accessed 3 May 2020. 2 HowStuffWorks.Com. “Electronic Cigarette.” HowStuffWorks, 2011, https://science.howstuffworks.com/innovation/everyday-innovations/electronic-cigarette1.htm 3 Margham, Jennifer, et al. "Chemical Composition of Aerosol from an E-Cigarette: A Quantitative Comparison with Cigarette Smoke." Chemical Research in Toxicology, vol. 29, no. 10, 18 Sept. 2016, pp. 1662-78. ACS Publications, https://pubs.acs.org/doi/10.1021/acs.chemrestox.6b00188. Accessed 3 May 2020. 4 Blaha, Michael Joseph, M.D., M.P.H., editor. "5 Vaping Facts You Need to Know." Johns Hopkins Medicine: Health, Johns Hopkins University, www.hopkinsmedicine.org/health/wellness-and-prevention/5-truths-you-need-to-knowabout-vaping. Accessed 3 May 2020. 5Gottschalk, Laura, et al. "Is Vaping Safer than Smoking Cigarettes?" Edited by Dr. Diana Zuckerman and other senior staff. National Center for Health Research, 2020, www.center4research.org/vaping-safer-smoking-cigarettes-2/. Accessed 3 May 2020. 6 Nichol, James, et al. "Comprehensive Chemical Characterization of the Aerosol Emissions of a Vaping Product Based on a New Technology." Chemical Research in Toxicology, vol. 33, no. 3, 3 Mar. 2020, pp. 789-99. ACS Publications, pubs.acs.org/doi/10.1021/acs.chemrestox.9b00442. Accessed 3 May 2020. 7 Harvard University. “Smoking machine.” The Harvard Gazette, The Harvard Gazette, https://news.harvard.edu/gazette/story/2016/11/creating-a-smokingmachine/
Chrysin’s Antioxidant Effects on the Nervous System Show Its Potential Therapeutic Significance Anyi Li
Abstract: Chrysin is a compound that is mostly found in various plants, honey and propolis. Chrysin is widely used as a nonprescription drug for bodybuilding, dealing with anxiety, or reducing inflammation. Recent research shows chrysin’s significance in controlling depression-like behavior of women. Chrysin (also called 5,7dihydroxyflavone, chemical formula: C15H10O4, structure is shown by figure 1) is a common member of the flavone family, which is a class of flavonoids that are common in plants.1
Figure 1: Structure of Chrysin.
Flavonoids are important component in the pigeon of plants, especially purple flowers, which indicates that it is a common chemical frequently ingested by humans. Additionally, Flavones do not have physiological effects in the human body and lack antioxidant food value.2 Chrysin, on the other hand, is not only found in plants like the passion flowers, but also found in products that are related to bees, for instance, honey and propolis.3
Chrysin is known for its function as an antioxidant. According to a group of researchers from Neyshabur University and Mashhad University in Iran, chrysin is one of the flavones that shows antioxidant properties, which is mainly supported by the double bond between carbons 2 and 3, and the carbonyl group on carbon 4 (see figure 1). Since ring B and ring C contain no oxygenation, chrysin is also related to other biological abilities like antitoxic and antiinflammatory effects.4 There has been abundant research about the physical benefit of honey. In 2014, two researchers from Chulalongkorn University, Thailand, Pongsathon Premratanachai and Chanpen Chanchao, wrote a review journal about propolis’s anticancer properties, among which chrysin plays an effective role. According to Premratanachai and Chanchao, chrysin has a broad influence on the apoptotic process.5 Despite flavonoids seems to be ineffective in human body, several recent researches show the potential therapeutic significant in cognition and nervous system of chrysin. Back in 1992, researchers from the Instituto de Biologfa Celular conducted an experiment on mice that indicates chrysin’s properties of anxiety decline. They used mice as experimental subjects, putting them into an elevated plus-maze (shown by figure 2) and observing the time they spent on the open and closed arms of the maze: greater trial times indicate anxiety in the mice, while low trial times reveal sedative activity.
Figure 2: Setting of an elevated plus-maze.
According to their experiment, chrysin has the potential ability of reducing anxiety among mice (see figure 3 below). However, this research group only tested chrysin contained medicine in living creatures, without explaining much about the biochemical process cause by the injection of chrysin in the living body.6
antidepressant-like effects of chrysin (see figure 4 for the graphing abstract).
Figure 4: A graphing abstract of the research of Cueto-Escobedo et al.
Figure 3: The mean percentage of open arm entries in the research of Instituto de Biologfa Celular. As shown by the figure, chrysin (CHRY) has lower open arm entries percentage than the comparison group, DZ, which is another medicine.
Moreover, a study in 2012 by the researchers from Research Center for Pharmacology and Toxicology shows that long-term treatment of chrysin significantly alleviates the neuronal damages which are increased accompanied by a large proliferation in glial fibrillary acidic protein. Similar to the prior experiment in 1992, they had chosen rats as their experimental subject. According to these researchers, the experiment on rats and the comparison on their escape latency in the Morris water maze shows that chrysin improves cognitive deficits. By the biochemical testing, researchers also found that chrysin reduced superoxide dismutase, indicating that it may have therapeutic potential for the treatment of neurodegeneration and dementia, which are caused by decreased cerebral blood flow.7 A recent research in October 2019 by Jonathan Cueto-Escobedo from Universidad Veracruzana et al. provides a deeper understanding about the 5
They explained the context that the neurobiology of depression is related to sexual hormone functions, resulting in females being at increased risk of depression than males due to the presence of ovarian hormones, which is a type of hormone that only exists in the female body. In the human brain, there exists steroid hormones like progesterone and allopregnanolone, which produce time-dependent effects on neurotransmitter pathways. One of the indirect actions to support this process can modulate the Îł-amino-butyric acid (GABA)ergic system, a neurotransmission that might decrease when the concentrations of steroid hormones are low in the human brain, causing people to present anxiety and depression-like behavior. GABAergic compounds include neurosteroids and plantderived flavonoids, which include chrysin as well. Same as the experiments in 2012, this group of researchers did their testing on rats by using the elevated plus-maze. However, this research on rats is focusing on finding out the effectiveness of GABAergic on ovarian hormones and female anxiety and depression-like behaviors, so they used female rats. The experiment they use is FST, which is a model that rats are forced to swim in without any possibility of escape, creating a valid chance to observe the anxiety of the subjects.8 According to their results, chrysin and fluoxetine “blocked the reduction of
grooming that was triggered by unpredictable chronic stress” (CuetoEscobedo, et al. 2020), presenting chrysin’s significance in reducing stress, anxiety, and depression-like behavior (see figure 5 for the table of the test). 9
Figure 5: The table that show the effect of treatment on crossing, rearing and grooming in the LAT. Data of rearing group and grooming group reflects the effectiveness of chrysin1 “Flavonoids.”
Linus Pauling Institute, Micronutrient Information Center, Oregon State University, 2 Apr. 2020, lpi.oregonstate.edu/mic/dietaryfactors/phytochemicals/flavonoids. 2 ibid. 3 ibid. 4 Samarghandian, Saeed, et al. “Protective Effects of Chrysin Against Drugs and Toxic Agents.” DoseResponse : a Publication of International Hormesis Society, SAGE Publications, 23 June 2017, www.ncbi.nlm.nih.gov/pmc/articles/PMC54844 30/ . 5 Premratanachai, Pongsathon, and Chanpen Chanchao. “Review of the Anticancer Activities of Bee Products.” Asian Pacific Journal of Tropical Biomedicine, Asian Pacific Tropical Medicine Press, May 2014, www.ncbi.nlm.nih.gov/pmc/articles/PMC398504 6/ . 6 Wolfman, Claudia, et al. “Possible Anxiolytic Effects of Chrysin, a Central Benzodiazepine Receptor Ligand Isolated from Passiflora Coerulea.” Pharmacology Biochemistry and Behavior, Elsevier, 26 Nov. 2002,
contained medicine in reducing anxiety and depression-like behavior.
This study also introduces GABAA receptor, which plays an effective role in the treatment of anxiolytic-like actions: “The binding of GABA with its receptor opens chloride ion channels to hyperpolarize the neuron and decrease neural activity. These neurophysiological actions are related to the anxiolytic effects of benzodiazepines, barbiturates, psychoactive drugs, and some neurosteroids” (Cueto-Escobedo, et al. 2020). Chrysin is able to interact with GABAA as well.10 Chrysin, as a component that is common in honey, plants, and many types of dietary supplies, shows its strong potential practice in anti-anxiety or antidepressant medications. Although there are still many properties of chrysin that remain unknown, such as whether its effect on male rats without ovarian hormones would be the same as on female rats, chrysin shows its therapeutic significance on physical and mental fields. www.sciencedirect.com/science/article/pii/009130 5 794901031. 7 He,
Xiao-Li, et al. “Chrysin Improves Cognitive Deficits and Brain Damage Induced by Chronic Cerebral Hypoperfusion in Rats.” European Journal of Pharmacology, U.S. National Library of Medicine, 5 Apr. 2012, www.ncbi.nlm.nih.gov/pubmed/22314218. 8 Can, Adem, et al. “The Mouse Forced Swim Test.” Journal of Visualized Experiments : JoVE, MyJove Corporation, 29 Jan. 2012, www.ncbi.nlm.nih.gov/pmc/articles/PMC3353513/ . 9 Cueto-Escobedo, Jonathan, et al. “Involvement of GABAergic System in the Antidepressant-like Effects of Chrysin (5,7-Dihydroxyflavone) in Ovariectomized Rats in the Forced Swim Test: Comparison with Neurosteroids.” Behavioural Brain Research, Elsevier, 14 Mar. 2020, www.sciencedirect.com/science/article/pii/S01664 3 2820302898. 10 ibid.
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A Brief Review of the Pharmacology of Psilocybin Cameron Behram Abstract: Following a decades-long hiatus in research after its classification as a Schedule I drug in the United States, psilocybin (4-phosphoryloxy-N,Ndimethyltryptamine) has become a new area of interest for those researching potential psychotherapeutic adjuncts. This article will briefly review the known pharmacology of psilocybin, as well as its pharmacokinetic and pharmacodynamic potential to both supplement therapeutic exercises in mentally ill individuals as well as help scientists better understand neurological mechanisms of sensory processing and even human consciousness as a whole due to its alteration in states of consciousness. Introduction: Psilocin, the psychoactive metabolite of the psilocybin found in psilocybin mushrooms (colloquially known as “magic mushrooms”) is a serotonergic hallucinogen that has recently become a focal point in the research of psychotherapeutic adjuncts. The use of psilocybin-containing mushrooms dates back to the Aztec Empire in shamanic and divinatory practices,1 but it was first chemically isolated by the now-famous Swiss chemist Albert Hoffman in 1957 and synthetically manufactured in 1958, when it was sold as an experimental psychotherapeutic adjunct under the name Indocybin® Sandoz after thorough human and animal testing.2 It has since been classified as a Schedule I drug in the United States, meaning that it has “no currently accepted medical use and a high potential for abuse”3, according to the United States Drug Enforcement Agency. This classification led to a 25-year-long gap in 7
research, until several breakthrough studies of psilocybin’s potential medical use drew attention from the scientific community, thus leading to a revival in both public and scientific interest in hallucinogens.4 The pharmacokinetics of psilocybin is now welldocumented, but vast amounts of research are being conducted to further understand its potential pharmacological uses to both ameliorate mental illness and better understand the mechanisms of the human brain due to its potent effects that alter the human state of consciousness. Pharmacokinetics of psilocin: Pharmacokinetics generally refers to the branch of pharmacology concerning a drug’s given mechanism of action and its physiological impacts on the human body. Recently, the scientific community has gained a comparatively thorough understanding of the pharmacokinetic mechanisms of psilocybin and psilocin through the use of modern brain imaging techniques. Upon oral ingestion of psilocybin, approximately 50% of it was actually absorbed into the bloodstream (calculated through isotropic labelling of the 14th carbon in psilocybin). Following absorption into the bloodstream, the psilocybin is enzymatically converted into 4 primary metabolites through a hepatic mechanism using the alkaline phosphatase enzyme. These metabolites consist of psilocin (4-hydroxy-N,N-dimethyltryptamine), which constitutes the primary metabolic product of psilocybin, which is further metabolized into 4-hydroxyindole-3yl-acetaldehyde, then into 4-hydroxyindole3-yl-acetic-acid and 4-hydroxytryptophol, which are largely clinically insignificant.2 The only clinically significant metabolite of psilocin is psilocin-O-glucuronide, which is the main urinary metabolite of psilocin and can be used to detect the presence of the drug.5 The specific metabolic pathway for psilocybin is pictured in Figure 1.
Figure 1: Metabolic Pathway of Psilocybin5
Pharmacodynamics of psilocin: As previously discussed, psilocin is the psychoactive metabolite of psilocybin that is actually responsible for the drug’s hallucinatory and psychoactive effects. Therefore, psilocybin is often classified as a prodrug, meaning that the molecule itself has no significant physiological impact on the body, but it gets metabolized into the actual psychoactive compound.5 The pharmacodynamic mechanism of action of psilocin in the brain has been elucidated through recent studies and imaging techniques, revealing that it acts as a 5hydroxytryptamine (5-HT2A) agonist due to its structural similarities to the neurotransmitter serotonin, which binds to these same receptors. It has a high binding affinity of Ki=6nM with 5-HT2A receptors in the brain, thus revealing that chemical interactions with this receptor is the genesis of the drug’s hallucinogenic and somatic effects. Moreover, while psilocin has not been shown to interact with D2 receptors (a part of the brain’s dopaminergic pathway), research suggests that this system is functionally altered as a result of alterations of the brain’s serotoninergic
Pathways.2 Furthermore, the use of PET (positron emission tomography) scans in 2 double-blind studies have elucidated the changes in metabolic consumption in the brain, thus revealing how psilocin alters brain activity in specific regions. It was found that neural metabolism increased by 25% in both the anterior cingulate gyrus (which regulates complex cognitive functions such as emotion and empathy) and temporal-medial cortex (which includes the hypothalamus and is responsible for the formation of explicit memories), by 24% bilaterally in the frontomedial and frontolateral cortex (which controls sensorimotor responses), by 19% in the basal ganglia (which regulates emotion and voluntary motor movement), and by 14% in the occipital cortex (which processes visual sensory stimuli). Conversely, metabolism decreased in the thalamus, which is the region that coordinates sensory input.6 These findings have immense implications relating to the psychopharmacology of the drug, as it drastically alters high-functioning cognitive areas of the brain without a high abuse potential due to its lack of interaction with D2 receptors, as an opiate would.7
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Pharmacology of psilocybin: The previously discussed pharmacokinetics and pharmacodynamics of psilocybin and psilocin contribute to their unique pharmacological identity, which manifests itself largely through psychic symptoms and largely inconsequential somatic symptoms. In a clinical setting, psilocybin’s primary objective would likely be treatment of psychological, rather than physical, ailments due to the overall lack of somatic effects,2 as pictured in Figures 2 and 3.
Figure 2: Somatic Symptoms of Psilocybin2 1 Nichols, David E. “Psychedelics.” Pharmacological
reviews vol. 68,2 (2016): 264-355. doi: 10.1124/pr.115.011478 2 Passie, Torsten, et al. "The Pharmacology of Psilocybin." Addiction Biology, digital ed., 2002, pp. 357-64. 3 "Drug Scheduling." United States Drug Enforcement Administration, DEA, www.dea.gov/drug-scheduling. Accessed 2 May 2020. 4 Carhart-Harris, Robin L., and Guy M. Goodwin. "The Therapeutic Potential of Psychedelic Drugs: Past, Present, and Future." Nature, 26 Apr. 2017. Nature, www.nature.com/articles/npp201784#cite as. Accessed 2 May 2020.
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Figure 3: Blood Pressure and Heart Rate Changes After Psilocybin Ingestion2
In fact, a thorough evaluation of both the physiological and psychological symptoms of psilocybin and psilocin suggests that it should be classified as a Schedule IV drug due to its low potential for abuse and low toxicity.6 Its actual clinical applicability, however, remains a point of contention among researchers and is currently being thoroughly investigated in various psychological contexts.4 However, this article will not delve into this, as it mainly aims to provide a review of what is already known about psilocybin and psilocin. Conclusion: After a long period of dormancy, a recent revival in interest regarding serotonergic hallucinogens as having potential clinical uses has led both scientists and society to rethink previous assertions regarding their use. As of the publication of this article, psilocybin has not yet been approved as a clinical treatment for psychological illnesses, but this very well may change in the coming years due to vast amounts of new research being conducted.4 5 Ricardo
Jorge Dinis-Oliveira (2017) Metabolism of psilocybin and psilocin: clinical and forensic toxicological relevance, Drug Metabolism Reviews, 49:1, 8491, DOI: 10.1080/03602532.2016.1278228 6 Vollenweider, F. X., M.D., et al. "Positron Emission Tomography and Fluorodeoxyglucose Studies of Metabolic Hyperfrontality and Psychopathology in the Psilocybin Model of Psychosis." Nature, vol. 17, May 1997, pp. 357-72, www.nature.com/articles/1380557.pdf. Accessed 3 May 2020. 7 Johnson, Matthew W et al. “The abuse potential of medical psilocybin according to the 8 factors of the Controlled Substances Act.” Neuropharmacology vol. 142 (2018): 143-166. doi:10.1016/j.neuropharm.2018.05.012
The Impact of Chocolate and Other Cocoa Products on Human Health Amanda Newcombe Abstract The large quantity of chocolate and cocoa products consumed throughout the world raises questions about their impact on health. This paper provides an historical and chemical background of chocolate and assesses the existing research about the positive impacts of chocolate and cocoa as well as what remains unclear about chocolate consumption. History and Background Chocolate has been a part of society from the time of the Olmecs, the first Mesoamerican civilization, that existed around 1500 BCA. In order for chocolate to be created from a cocoa bean, the bean must be fermented, dried, and roasted. During the anaerobic phase of fermentation, amino acids and peptides are the major nitrogen-containing flavors. However, during the drying stage many of the acids, such as acetic acid, are lost.1 Therefore, the health benefits of consuming cocoa may be different than the health benefits of consuming chocolate. Of the different types of chocolate, the more cocoa solids in a chocolate, the closer that chocolate will be to resembling cocoa. Additionally, the structural makeup of the chocolate varies depending on the type. The chemical makeup of different cocoa products can vary the health benefit of the product significantly. Cocoa contains high levels of antioxidants, the most abundant of which is procyanidin. Since darker chocolates contain more cocoa solids than other chocolates, they typically have higher levels of antioxidants and procyanidins. However, baking chocolates contain fewer procyanidins due to having a
higher fat content (50-60 percent) than natural cocoa. Also, chocolates that has undergone alkalization, such as Dutch chocolates, have significantly reduced amounts of procyanidin and therefore have fewer antioxidants.2 Chocolate is the richest natural source of theobromine, which is similar to caffeine. Because dark chocolate has more cocoa solids, it has more theobromine, and white chocolate, which contains only cocoa butter and does not have cocoa solids, only has a minimal amount of theobromine. Theobromine, which provides a lift after eating chocolate, is easily metabolized by humans, but it is hard for cats and dogs to metabolize, causing chocolate to be toxic to them.3
Figure 1: the basic chemical differences of dark, milk, and white chocolate3
Chocolate can also be used as a functional food, meaning that it provides health benefits beyond basic nutrition. While protein, fat, carbohydrates, vitamins, and minerals are considered basic nutritional needs, chocolate also has benefits to other aspects of human health, including a lower cardiovascular mortality and a decreased risk of high blood pressure.4
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Health Impact of Chocolate In addition to being a functional food and providing an energy boost, chocolate and other cocoa products have positive health benefits as they lower the risk of cardiovascular disease and contain antioxidants. A 2012 article published in the American Journal of Clinical Nutrition reviewed research regarding the health impact of chocolate, and it was found that the health benefits of consuming cocoa or dark chocolate outweigh the risks. The risks of consuming chocolate come from the sugar, fat, calories, and caffeine it contains, but this study concluded that cocoa and dark chocolate can also decrease cardiovascular disease risk and mortality, reduce insulin resistance, and have positive effects on fibromuscular dysplasia (FMD).5 The study included two people separately reviewing articles to decrease the bias before focusing the review on 42 of the most controlled and on-topic articles. The participants in the studies included healthy people as well as people who were overweight, had high blood pressure, had high serum total cholesterol levels, were type two diabetic, had cardiovascular disease risk, had stable coronary artery disease, had congestive heart failure, had smoking related endothelial dysfunction, had chronic fatigue, or had hypertensions and impaired glucose tolerance. Within the studies, there was a variation in the way the cocoa products were consumed, including consumption via cocoa drinks, dark or milk chocolate, cocoa supplements, solid chocolate plus cocoa drinks, or a whole diet which included cocoa powder and chocolate. In all the trials, the effects from the cocoa was compared to effects of low flavan-3-ol versions of the same foods, allowing the study to identify the health impact of the flavan-3-ols in chocolate.5 Flavan-3-ols are what provide the bitter taste in cocoa because they form complexes with salivary proteins. In 11
chocolate, the bitter flavor from the flavan3-ols is often masked by other flavors. The primary flavan-3-ols in cocoa are epicatechin, catechin, and procyanidins, and the procyanidins are primarily responsible for the antioxidant activity in cocoa products. The aromatic rings in the flavan3-ols can neutralize free radicals, chelate metals that enhance reactive oxygen species, inhibit enzymes, and upregulate antioxidant defenses.6
Figure 2: the basic structure of a flavan-3-ol with different R groups depending on the type5
The study found that consumption of chocolate or cocoa reduced insulin resistance because of a decrease in insulin secretion. Also, it was found that the chocolate or cocoa had beneficial effects on FMD, which proved to be stable to sensitivity analysis. Reductions in diastolic blood pressure, triglycerides, and average arterial pressure were also found, but these results were less stable in the sensitivity analysis. The same results occurred with LDL and HDL cholesterol, and significant effects on systolic blood pressure and CRP concentrations were found. However, when cocoa or chocolate consumption was combined with other dietary interventions, beneficial effects on HDL cholesterol were greater in longer-term trials and increasing the epicatechin dose led to significant improvements in FMD following acute intake. Overall, based off the limited data in this study, a notable relationship between
chocolate or cocoa intake and cardiovascular health indicates that increased consumption of chocolate or cocoa results in lower blood pressure and lower risks of stroke and cardiovascular mortality. 5 Additional research has since shown that the cause of flavan-3-ols resulting in lower blood pressure is due to flavanols producing nitric oxide in the endothelium, the lining of blood vessel cells. This occurrence can help to relax blood vessels and improve blood flow, therefore lowering blood pressure. Additionally, because the flavan-3-ols in chocolate have been proven to reduce insulin resistance in short term studies, in the long this could reduce the risk of diabetes.7 Due to the negative effects that over consumption of chocolate could have on human health, it is important to understand the quantity of chocolate needed in order to
receive the health benefits of chocolate. A 2017 study found that consuming more than one to three 30-gram servings of chocolate a week does not further increase the health benefits. Another study done at the same time suggests that older adults who consumed 10 grams of any type chocolate everyday had better cognitive function than non-chocolate eaters, and the people who consumed dark chocolate had a lower risk of mild cognitive impairment. However, this study on the cognitive impact of chocolate could have been affected by other lifestyle, dietary, or genetic factors.8 Overall, cocoa and chocolate consumption has been proven to have positive effects on cardiovascular health, insulin resistance, and fibromuscular dysplasia due the flavan-3-ols and their antioxidant priorities, but research still needs to be done to determine the long-term impact of cocoa and chocolate consumption.
1 Tannenbaum,
5 Hooper,
Ginger. “Chocolate: A Marvelous Natural Product of Chemistry.” Journal of Chemical Education, Edited by George Kauffman, vol. 81, 1 Aug. 2004, pp. 1131–1135., https://people.chem.umass.edu/mcdaniel/chem26 9 /experiments/trimyristin/chocolate-and-itscomplexity.pdf. 2 Core,
Jim. “In Chocolate, More Cocoa Means Higher Antioxidant Capacity.” Agricultural Research Service U.S. DEPARTMENT OF AGRICULTURE, 4 Apr. 2005, www.ars.usda.gov/newsevents/news/research-news/2005/in-chocolatemore-cocoa-means-higher-antioxidant-capacity/. 3 Bigler,
Abbey. “The Chemistry of Chocolate.” National Institute of General Medical Sciences, U.S. Department of Health and Human Services, 12 Feb. 2020, biobeat.nigms.nih.gov/2020/02/the- chemistry-ofchocolate/. 4 Albrecht,
Julie A, et al. “Http://Extensionpublications.unl.edu/Assets/P df/ hef599.Pdf.” University of Nebraska Lincoln Extension, University of Nebraska, 2012, extensionpublications.unl.edu/assets/pdf/hef599.pdf.
Lee A, et al. “Effects of Chocolate, Cocoa, and Flavan-3-Ols on Cardiovascular Health: a Systematic Review and Meta-Analysis of Randomized Trials.” The American Journal of Clinical Nutrition, vol. 95, no. 3, Jan. 2012, pp. 740–751., https://academic.oup.com/ajcn/article/95/3/740/ 4576702. 6 Katz,
David L, et al. “Cocoa and Chocolate in Human Health and Disease.” Antioxidants & Redox Signaling, vol. 15, 15 Nov. 2011, pp. 2779–2811., https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4 696435/. 7 “Dark
Chocolate.” The Nutrition Source, Harvard T.H. Chan School of Public Health, 4 Nov. 2019, www.hsph.harvard.edu/nutritionsource/foodfeatures/dark-chocolate/. 8 “Should
You Show Your Love with (Chocolate) Flavonoids?” Tufts Health & Nutrition Letter, Tufts University, 17 Jan. 2019, www.nutritionletter.tufts.edu/healthyeating/should- you-show-your-love-with-chocolateflavonoids.
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Artificial Food Coloring and its Effects on Human Health Theo Camille Burden Abstract: The use of artificial food coloring in our food has become more prevalent in our society. Some color additives are used to enhance natural colors, add color, or help identify flavor. Many artificial food colorings have been recognized by some to impose certain health risks. This paper evaluates the various types of artificial food coloring along with its potential effects on human health. The use of artificial coloring dates all the way back to ancient times, around 300 BC, when wine was beginning to be artificially colored. Natural color additives from vegetable and mineral sources were used to color food, drugs, and cosmetics (paprika, turmeric, saffron, and iron for example). Over time discoveries of synthetic organic dye started to emerge with the first discovery being mauve by British chemist, William Henry Perkin, in 1856. As more and more discoveries of dyes emerged the United States began the federal oversight initiative in 1881 with the U.S. Department of Agriculture’s (USDA). Their Bureau of Chemistry began research on the use of added colors in food with cheese and butter being the first foods the federal government authorized the use of artificial coloring for. Artificial food coloring was more widespread in the U.S. by the 1900’s, even though not all were harmless. Most color additives were used to hide the imperfections in food through added lead, arsenic, and mercury. As a result, Congress passed the Food and Drug Act in 1906 that prohibited the use of poisonous coloring or using color additives to hide the imperfections in food. The Food and Drug Administration (FDA) was
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responsible for enforcing the Food and Drug Act of 1906 in 1927. Four years later, in 1931, there were 15 colors approved for the use of food that have not been mixed or chemically reacted with any other substance, some of which are still use in our food today, such as, Blue No. 1, Blue No. 2, Green No. 3, Red No. 3, Yellow No. 5, and Yellow No. 6.1 As of recently there are nine FDA approved color additives, including those previously mentioned, along with Orange B, Red No. 2, and Red No. 40.2 Color additive derived from petroleum are found in several food products, such as breakfast cereal, snacks, beverages, vitamins, and products advertised for children. The FDA approved artificial food coloring derived from petroleum in order to enhance the appearance of foods. For example, some fresh oranges are dipped in coloring to brighten them up. It’s also said to be that the cereal “Cap’n Crunch’s Oops! All Berries” has the most color additives with 41 mg of dye.3 Over time some of the dyes have posed as health risks and some were even banned in certain continents. In 2010 the Center for Science in the Public Interest (CSPI) in Washington, DC did a report where they found that “the nine artificial dyes approved in the United States likely are carcinogenic, cause hypersensitivity reactions and behavioral problems, or are inadequately tested”.4 There have been studies to show how the effects of dye consumption can have an impact on a child’s behavior. Although, the studies are inaccurate since the dye dosage the children are given are far less than the amount of dye being consumed daily. The typical daily dosage of Red No. 40 is 10 mg, according to an exposure assessment by the FDA in 2014, whereas people consume as much as 52 mg of a single dye in one day. With trying to observe the effects artificial food coloring has on a child’s behavior there
are two general studies that come about, the studies that gave children food dye and see how they respond, or, the studies that eliminate certain dye containing foods from a child’s diet and observing their reaction. Some of the results of the studies showed that even the smallest amount of artificial dye, smaller than a cupcake, can spark adverse behavioral changes. Not only in children with behavioral disorders, but those without. These studies believe that artificial dyes can trigger ADHD symptoms which can be altered by dietary changes. The overall conclusions of these studies being that behavioral improvements for some children is possible by either eliminating food dyes completely or taking on a broader diet to eliminate them.5 Even though these studies conducted found somewhat of a behavioral change, this is not the case in all children. Some target “elimination diets” for artificial food since “they serve no health purpose whatsoever”, says, Michael Jacobson, director of the Center for Science in the Public Interest (CPSI).6 Although, in a small study with 26 children with ADHD, 73% of the children experienced “a decrease in symptoms when artificial food dyes and preservatives were eliminated”.7 There are many debates surrounding the topic of artificial food coloring and behavior problems in relation to ADHD as a result of insufficient data conclusions. As well as the effects artificial coloring has on hyperactivity varies from child to child.8 Along with hyperactivity there’s a growing concern that some color additives contain a
chemical that could increase the risk of bladder cancer. There have been three color additives that have been identified as containing a human and animal carcinogen*. FDA and Canadian government scientists found that Red No. 40, Yellow No. 5, and Yellow No. 6 have some containments of carcinogen. It was found by the FDA in 1985 that the “ingestion of free benzidine† raises the cancer risk to just under the “concern” threshold (1 cancer in 1 million people)”.9 Although the odds might appear minimal, the FDA only primarily test free benzidine, but overlook the bound benzidine. The dangers in bound benzidine are much greater than free benzidine since it comes in greater amounts, “so we could be exposed to vastly greater amounts of carcinogens than FDA’s routine tests indicate” (Michael Jacobson).10 Even though this is a concern brought by the CPSI, the FDA are unable to comment on topics under review so their position towards the issue is unknown. Moreover, the FDA has established legal limits to regulate cancer-causing containments in certain dyes. Although their efforts were to help prevent this health concern, the FDA didn’t consider in their tests the increased risks dyes have on children. Children consume much more artificial dyes than adults and they are more sensitive to carcinogens. Another risk that the FDA is failing to realize in their study on artificial dyes is the effect they have on the human body collectively, rather than independently.11 Since the use of artificial dyes are mainly advertised towards children, they are consuming large dye amounts of various types. For example, if a child were to
*A
substance capable of causing cancer in living tissue. † Free benzidine is an organic based manufactured chemical that was previously used to produce dyes for cloth, paper, and leather.
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eat a pack of jellybeans, they’re consuming a large amount of Red No. 40, Yellow No. 6, and Blue No. 1.12 As a result, it would be more beneficial in their lab work to test the effects of the consumptions of multiple color additives. With the growing concern that artificial dyes do not improve the safety or nutritional value in foods it has come to the attention of Michael Jacobson that, “all of the currently used dyes should be removed from the food supply and replaced, if at all, by safer colorings”.13 There has been an increase effort in trying to regulate artificial coloring. Manufactures overseas are considering using natural dyes that are made from beets and turmeric. The United States is also considering using natural dyes rather than artificial, although the only thing preventing them from doing so is how expensive natural dyes are and how they are less stable than artificial dyes.14 Meanwhile, still disturbed by the health concerns coloring additives have the Center for Science in the Public Interest is requesting that the FDA ban the following artificial food dyes in Figure 1 and in Figure 2.15 1 Barrows,
Julie N., et al. "Color Additives History." Edited by Sebastian Cianci. U.S. Food and Drug Administration, 3 Nov. 2017, www.fda.gov/industry/color-additives/coloradditives-history. 2 "Color Additives Questions and Answers for Consumers." U.S. Food and Drug Administration, 4 Jan. 2018, www.fda.gov/food/food-additivespetitions/color-additives-questions-andanswers-consumers. 3 Hennessy, Maggie. "Purdue Study: Artificial Dyes Highest in Beverages, Cereal, and Candy." Food Navigator, 7 May 2014, www.foodnavigator-usa.com/Article/ 2014/05/08/Purdue-study-Artificial-dyes-highestin-beverages-cereal-candy. 4 Potera, Carol. "Diet and Nutrition: The Artificial Food Dye Blues." Environmental Health Perspectives,
15
Figure 1: List of Artificial Food Coloring the CPSI hopes the FDA will ban16
Figure 2: List Continued
www.ncbi.nlm.nih.gov/pmc/articles/PM C2 957945/. 5 Lefferts, Lisa Y. Seeing Red. Edited by Michael F. Jacobson and Laura MacCleery, e-book. 6 Woodman, Dawnielle. "FDA Probes Link between Food Dyes, Kids' Behavior." Interview conducted by April Fullerton. National Public Radio, 30 Mar. 2011, www.npr.org/2011/03/30/134962888/. 7 Bell, Becky. "Food Dyes: Harmless or Harmful?" Healthline, 7 Jan. 2017, www.healthline.com/nutrition/food-dyes/. 8 Office of Food Additive Safety, Center for Food Safety and Applied Nutrition, Food and Drug Administration. "Artificial Food Color Additives and Child Behavior." Environmental Health Perspectives, www.ncbi.nlm.nih.gov/pmc/ articles/PMC3261955/.
13 S.,
9 Potera, Carol. "Diet and Nutrition: The Artificial Food Dye Blues." Environmental Health Perspectives, www.ncbi.nlm.nih.gov/pmc/articles/PMC29579 45/ . 10 Potera, Carol. "Diet and Nutrition: The Artificial Food Dye Blues." Environmental Health Perspectives, www.ncbi.nlm.nih.gov/pmc/articles/PMC29579 45/ . 11 Kobylewski, Sarah, and Michael F. Jacobson. "Food Dyes: A Rainbow of Risks." Center for Science in the Public Interest, PDF ed. 12 Woodman, Dawnielle. "FDA Probes Link between Food Dyes, Kids' Behavior." Interview conducted by April Fullerton. National Public Radio, 30 Mar. 2011, www.npr.org/2011/03/30/134962888/.
Kobylewski, and Jacobson M. "Toxicology of Food Dyes." PubMed, www.ncbi.nlm.nih.gov/pubmed/23026007. 14 Woodman, Dawnielle. "FDA Probes Link between Food Dyes, Kids' Behavior." Interview conducted by April Fullerton. National Public Radio, 30 Mar. 2011, www.npr.org/2011/03/30/134962888/. 15 Woodman, Dawnielle. "FDA Probes Link between Food Dyes, Kids' Behavior." Interview conducted by April Fullerton. National Public Radio, 30 Mar. 2011, www.npr.org/2011/03/30/134962888/.
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Acrylamide: A Review of Its Formation and Health Effects Josh Lobsenz Abstract: With the rise of genetically modified organisms and public support of food being “locally sourced”, “organic”, or “farm-to-table”, chemicals within food, such as acrylamide, have come under scrutiny. This paper will examine how acrylamide is formed in food and its potential health effects on humans. Acrylamide is a chemical that is found in foods when cooked with certain hightemperature methods,1 such as frying and grilling. It consists of an amide whose nitrogen is bonded to two hydrogens and whose carbon is bonded to an ethene (see Figure 1 below).
Figure 1: The structure of acrylamide.2 Acrylamide is formed via the Maillard reaction. In general, a Maillard reaction consists of a reducing sugar reacting with an amino acid at a high temperature; since almost all food contains at least some sugars and protein, Maillard reactions occur when food is cooked. It can manifest itself as the browning and flavor of meat, the color of toast, and the taste and golden-brown color of fried food.3 So how does the reaction work? (In order to simplify, this paper will only discuss the Maillard reaction with regard to creating acrylamide, as Maillard reactions can produce a multitude of other compounds.)
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The process begins with one of a handful of amino acids: asparagine, methionine, glutamine, cystine, and aspartic acid. Of these, asparagine is most commonly referenced and results in the highest levels of acrylamide, so it will be the amino acid used in this paper’s mechanism. Asparagine reacts with a sugar’s carbonyl group, and, via dehydration, a double bond is created between the non-amidic nitrogen and the formerly carbonyl carbon, resulting in a Schiff base (see Figure 2).
Figure 2: A Schiff base.4 The Schiff base releases a carbon dioxide molecule, and the nitrogen accepts a hydrogen atom, making it positively charged; this causes the double bond and negative charge to alternative between the two carbons, creating resonance. Both forms of the molecule become acrylamide, though by different means. In one, a hydrogen shifts onto the anionic carbon, stabilizing it, breaking it off from the nitrogen, and creating acrylamide. For the other form of the resonant molecule, water enters the system and breaks it up into an aldehyde and 3aminoproprionamide; in the latter of these, the nitrogen takes a hydrogen atom from the carbon and breaks free, forming ammonia. The unstable carbon then accepts a hydride shift and forms a double bond with the adjacent carbon, creating acrylamide.5,6,7 The mechanism is shown in Figure 3. Temperature is also an important factor in the accumulation of acrylamide (see Figure 4). Acrylamide will not form below
120 degrees Celsius, and it peaks at about 170 degrees Celsius with levels around 450 milligrams per mole.8 Additionally, the longer a food is cooked at a high temperature, the more acrylamide forms.
Figure 3: The mechanism for the formation of acrylamide.9
Figure 4: Amount of acrylamide produced at different temperatures from 0.1 mmol asparagine and 0.1 mmol glucose in 0.5 M phosphate buffer.10 As previously noted, asparagine is the amino acid most likely to form acrylamide.
However, this does not necessarily mean that foods high in asparagine have high levels of acrylamide. For instance, asparagus, the namesake of asparagine, generally has very little acrylamide,11 though this may be due to the fact that asparagus is typically steamed or boiled, cooking methods that do not result in the formation of acrylamide. The foods most mentioned as having high acrylamide levels are potatoes, particularly when they are fried at high temperatures; grains, such as cereal and toast; and coffee. Interestingly, meat does not have a lot of acrylamide, even when it is fried or burnt. (While there is concern that burnt meat can cause cancer, this is due to the formation of heterocyclic amines rather than acrylamide.12) This could be due to the fact that meat has very few sugars in it.13 As a side note, potatoes are high in asparagine and carbohydrates, which explains why they have high acrylamide levels. In order to reduce acrylamide accumulation, scientists have developed genetically modified potatoes that decrease the amount of glucose and fructose in the potato. This has shown to be effective in lowering the potatoes’ acrylamide levels (see Figure 5 below).14
Figure 5: Acrylamide levels in different genetically modified potatoes compared to the non-GMO potato.15 With all this discussion of acrylamide, what is its impact on human health? Do concerns about it have any basis in research?
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The greatest worry about acrylamide is that it is carcinogenic. In studies, animals that were given higher doses of acrylamide were more likely to develop cancer. Additionally, several organizations, such as the International Agency for Research on Cancer, the United States National Toxicology Program, and the United States Environmental Protection Agency, all say that acrylamide is probably carcinogenic in humans.16 The human body converts acrylamide into glycidamide (see Figure 6), which is known to alter and damage DNA. Despite this, studies in humans have not shown that increased intake of acrylamide leads to a higher cancer risk; this could be because humans process acrylamide differently than animals or because it is harder to control and account for confounding variables in humans. The United States Food and Drug Administration has urged for more longterm studies on the toxicity of acrylamide.17
Since its discovery in food in 2002, acrylamide has been the subject of much discussion in the scientific community and concern in the general public. Even though it is formed from delicious chemical reactions, it may be harmful to humans. That being said, some reactions to it may be overstated; more research needs to be done to determine how dangerous it really is.
1 "Acrylamide
10 Mottram,
Questions and Answers." FDA, U.S. Food & Drug Administration, www.fda.gov/food/chemicals/acrylamidequestions- and-answers. Accessed 3 May 2020. 2 "Acrylamide." Wikipedia, en.wikipedia.org/wiki/Acrylamide. Accessed 3 May 2020. 3 "What is the Maillard Reaction?" Science of Cooking, www.scienceofcooking.com/maillard_reaction.htm. Accessed 3 May 2020. 4 Zyzak, David V., et al. "Acrylamide Formation Mechanism in Heated Foods." Journal of Agricultural and Food Chemistry, vol. 51, no. 16, 30 July 2003, pp. 4782-87, DOI:10.1021/jf034180i. Accessed 3 May 2020. 5 Mottram, Donald S., et al. "Acrylamide Is Formed in the Maillard Reaction." Nature, vol. 419, no. 6906, 3 Oct. 2002, pp. 448-49. 6 Stadler, Richard H., et al. "Acrylamide from Maillard Reaction Products." Nature, vol. 419, no. 6906, 3 Oct. 2002, pp. 449-50. 7 Zyzak, David V., et al. 8 Mottram, Donald S., et al. 9 Stadler, Richard H., et al.
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Figure 6: The structure of glycidamide, a mutagenic compound which acrylamide converts into.18
Donald S., et al. Is Acrylamide and How Is It Involved with Food and Health?" The World's Healthiest Foods, www.whfoods.com/genpage.php?tname=george&dbi d=260. Accessed 4 May 2020. 12 "Meat and Cancer." Cancer Council NSW, www.cancercouncil.com.au/21639/ cancer-prevention/diet-exercise/nutritiondiet/fruit- vegetables/meat-and-cancer/. Accessed 4 May 2020. 13 “Acrylamide Questions and Answers.� 14 Rommens, Caius M., et al. "Low-acrylamide French Fries and Potato Chips." Plant Biotechnology Journal, vol. 6, no. 8, Oct. 2008, pp. 843-53. 15 Ibid., 847. 16 "Acrylamide and Cancer Risk." American Cancer Society, www.cancer.org/cancer/cancercauses/acrylamide.html. Accessed 4 May 2020. 17 "Acrylamide and Cancer Risk." National Cancer Institute, NIH, www.cancer.gov/aboutcancer/causes-prevention/risk/diet/acrylamidefact- sheet. Accessed 4 May 2020. 18 Glycidamide (CAS 5694-00-8). Santa Cruz Biotechnology, www.scbt.com/p/glycidamide5694- 00-8. Accessed 4 May 2020. 11 "What
An Analysis of the Biochemical Mechanisms of Stress in the Brain Charlotte Wenk Abstract: Any stimulus, external or internal, that causes a biological response is known as stress, and the compensatory responses to these stresses are known as stress responses. This article will elaborate on what the stress response is, and what occurs neurochemically and hormonally throughout the brain and body during the stress response. Introduction: When a sequence of events consisting of an external or internal stimulus that causes a reaction in the brain, it then activates a physiological fight or flight system in the body.1 This fight or flight system is commonly known as the stress response. Psychological, physiological, and physical, stressors all activate biological stress responses; the biological stress responses involve the release of hormones in the systemic circulation and within central and peripheral tissues. Stress Hormones: The stress response consists mainly of three hormones, norepinephrine and epinephrine, and cortisol. The sympathetic nervous system or SNS releases norepinephrine and epinephrine (as well as adrenaline and noradrenaline) from the adrenal medulla.2 Cortisol is induced by the adrenal gland in the zona fasciculata after the hypothalamicpituitary-adrenal axis or HPA is activated. 1
Dhabhar, Furdaus S., and Bruce S. Mcewen. "Acute Stress Enhances while Chronic Stress Suppresses Cell-Mediated Immunity." Brain, Behavior, and Immunity, vol. 11, no. 4, Dec. 1997, www.sciencedirect.com/science/article/abs/pii/ S08 89159197905080. Accessed 16 May 2020.
Additionally, the HPA axis is responsible for releasing neuropeptides and hormones in the spinal cord, medulla, pons, and higher order centers like the hypothalamus. (See Fig. 1)3 Almost every cell in the body has receptors for cortisol, norepinephrine and epinephrine. These receptors induce changes in cells and tissues throughout the entire body and inform them about the presence of the given stressor.
(Fig 1) Internal Stimuli: Psychological stressors, or stress due to hypothetical events that are not physically occurring, are primarily processed by the limbic system (see Fig. 2), including the hippocampus, amygdala and prefrontal cortex. Both the hippocampus and the amygdala are rich in receptors for cortisol. Amygdala stimulation can provoke the bed nucleus of the stria terminalis to cause the release Corticotropin-Releasing Enhancing Protection and Performance Under Conditions of Threat, Challenge, and Opportunity." NCBI, 26 Mar.2018, www.ncbi.nlm.nih.gov/pmc/articles/PM C596 013/. Accessed 16 May 2020. 3
Ibid
2Dhabhar,
Firdaus S. "The Short-Term Stress Response – Mother Nature's Mechanism for
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Hormone or CRH. CRH then causes the adrenal gland to release epinephrine & cortisol.4 The hippocampus is responsible for the intrusive thoughts and memories that occur when one is presented with psychological stressors or internal stimuli. The prefrontal cortex is responsible for the behaviors that occur due to the stressor.
The Formation of Glucocorticoids: CRH is not only prevalent with Psychological stressors, CRH is the major physiological activator of the HPA axis. It coordinates the neuroendocrine response to stress. CRH is released from parvocellular neuroendocrine neurons of the paraventricular nucleus of the hypothalamus (PVN). These neurons release CRH into the hypophyseal portal vasculature (blood vessels in the microcirculation at the base of the brain, connecting the hypothalamus with the anterior pituitary). The hypophyseal portal system transports CRH to secretory corticotrope cells in the anterior pituitary. The cells in the anterior pituitary gland then express the CRF receptor type 1. The activation of CRFR1 stimulates the release of Adrenocorticotropic hormone (ACTH) and other pro-opiomelanocortin (POMC) derived peptides. Finally, ACTH, triggers the synthesis and release of GCs from the adrenal cortex.6
(Fig. 2) External Stimuli: Conversely, physical stressors are not processed, at least fully, in the limbic system. Stress caused by physical factors cause the rapid activation of the SNS and the HPA axis. This, in turn, regulates the release of glucocorticoids (GCs) from the HPA axis. GCs mediate numerous physiological and metabolic reactions which prepare one to deal with the stressful situation. However, the process to form GCs from CRH hormones is very complex.5
(Fig. 3)
4
Chrousos, G. P., and P. W. Gold. "The Concepts of Stress and Stress System Disorders. Overview of Physical and Behavioral Homeostasis." nih.gov, 8 July 1992, pubmed.ncbi.nlm.nih.gov/1538563/. Accessed 16 May 2020.
5Dedic,
Nina, et al. "The CRF Family of Neuropeptides and their Receptors - Mediators of the Central Stress Response." nih.gov, 11 Feb. 2018, www.ncbi.nlm.nih.gov/pmc/articles/PMC593045 3/ #r19. Accessed 16 May 2020. 6 Ibid
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Functions and Effects of Glucocorticoids: The GCs mediate numerous physiological and metabolic reactions and ultimately prepare the organism to deal with the stressful situation. These responses to GCs affect many bodily systems. For example, the musculoskeletal system, as stress causes muscle tension. Stress also affects the respiratory system. Stress causes shortness of breath and rapid breathing (hyperventilation). Stress also affects the cardiovascular system; Adrenaline, noradrenaline and cortisol causes an increase in heart rate and stronger contractions of the heart muscle. And, the blood vessels that direct blood to large muscles dilate. This increases the amount of blood pumped to specific parts of the body and elevates blood pressure. The gastrointestinal system is affected as the brain-gut communication is affected by stress. Millions of bacteria inhabit the gut i
Chrousos, G. P., and P. W. Gold. "The Concepts of Stress and Stress System Disorders. Overview of Physical and Behavioral Homeostasis." nih.gov, 8 July 1992, pubmed.ncbi.nlm.nih.gov/1538563/. Accessed 16 May 2020. Dedic, Nina, et al. "The CRF Family of Neuropeptides and their Receptors - Mediators of the Central Stress Response." nih.gov, 11 Feb. 2018, www.ncbi.nlm.nih.gov/pmc/articles/PMC593045 3/ #r19. Accessed 16 May 2020. Dhabhar, Firdaus S. "The Short-Term Stress Response – Mother Nature's Mechanism for Enhancing Protection and Performance Under Conditions of Threat, Challenge, and Opportunity." NCBI, 26 Mar. 2018, www.ncbi.nlm.nih.gov/pmc/articles/PMC596401 3.
7
Stress effects on the body." American Psychological Association, 2020, www.apa.org/helpcenter/stressbody. Accessed 16 May 2020.
which influence its health and the brain’s health. The changes in gut bacteria can influence mood and emotions. Stress can cause, acid reflux, heartburn, bloating, nausea, stomach pain, vomiting, change in appetite, diarrhea, constipation. All of these possible symptoms are due to that stress affects every aspect and every organ in digestion. 7GCs also restore the HPA axis to its normal state after the body has reacted to the stressor. GCs signal back via glucocorticoid (GR) and mineralocorticoid receptors (MR) which reside in the cytoplasm of cells. The GRs and MRs mediate the genomic actions of GCs by acting as nuclear transcriptional activators and repressors. Membrane bound GRs mediate the rapid actions of GCs which consequently halts the secretion of CRF and then ACTH. (See Fig 3.) 8 i
Accessed 16 May 2020 Dhabhar, Furdaus S., and Bruce S. Mcewen. "Acute Stress Enhances while Chronic Stress Suppresses Cell-Mediated Immunity." Brain, Behavior, and Immunity, vol. 11, no. 4, Dec. 1997, www.sciencedirect.com/science/article/abs/pii/ S08 89159197905080. Accessed 16 May 2020. Srinivasan, Subhashini, et al. "The role of the glucocorticoids in developing resilience to stress and addiction." Frontiers in Psychiatry, 1 Aug. 2013, www.frontiersin.org/articles/10.3389/fpsyt.2013.000 68/full. Accessed 16 May 2020. "Stress effects on the body." American Psychological Association, 2020, www.apa.org/helpcenter/stressbody. Accessed 16 May 2020.
8Srinivasan,
Subhashini, et al. "The role of the glucocorticoids in developing resilience to stress and addiction." Frontiers in Psychiatry, 1 Aug. 2013, www.frontiersin.org/articles/10.3389/fpsyt.20 13.00068/full. Accessed 16 May 2020.
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