Can We Reverse Cell Aging?

By: Dr. Alwyn Wong

Despite our best efforts, our pursuit of optimal health often falls short. And that only increases with age.

With the passage of time, the number and types of stressors in all our lives increase. Stress comes in many forms – physical, emotional, financial, psychological – but the result is the same: a part of the brain known as the hypothalamus stimulates the pituitary gland to release a hormone called ACTH (adrenocorticotropic hormone) which then acts on the adrenal glands that sit on top of each kidney. This triggers the kidneys to release the hormone cortisol.

Too much cortisol can lead to cellular destruction called senescence. When cells become senescent or aged, they stop behaving as they were designed to. Regardless of what we call it, a hallmark feature of cellular destruction or senescence is the release of pro-inflammatory chemicals known as cytokines, proteases, and miRNAs. Stress- induced senescence also causes both DNA damage and alteration, leading to chemicals that cause nearby cells to break down, resulting in a cascade of destruction and rapid aging.

Yikes! That’s a whole lot of scary science! So, how does the process of stress and aging make our fitness efforts futile? Problems arise when senescence affects muscle, nerve, and even fat cells that can lead to a disruption of function and an array of negative health effects and diseases.

But can the stress-senescence axis affect cells that have yet to become what they’re meant to be – our stem cells?

Let’s take one more dive into the scientific muck to discuss stem cells and progenitor cells.

Stem cells, the focus of much research over the last ten years, by contrast have the potential to develop or differentiate into various cell types, including muscle, nerve and fat cells,

among others. Stem cells hang out idly on the sidelines waiting to be put on the field or court. When called upon, these cells replace damaged cells and repair damaged tissues and organs, including muscles, nerves, and fat cells.

Progenitor cells are the next step in stem cell differentiation but they can only further develop into the cells that they’re designed to become. For example, a progenitor nerve cell can only become a fully functional nerve cell. These cells have to remain healthy in order for our body to recover from various stressors. And that’s the rub. In response to stress, cells including stem and progenitor cells are subject to harm. When these cells become damaged, aged or senescent, our bodies experience the negative effects.

A hallmark of senescence is inflammation, cell destruction, and the stimulation of nearby cells to break down. The outcome, common to all cell types, is the inability of a cell to divide properly, resulting in large and damaged cells.

HAEMOPOETIC STEM CELLS

Luckily, while the stem cells responsible for making blood actually decline in number as we age, their collective production of blood cells does not. This is thanks to increased production by healthy, functional stem cells. Despite this, mild anemia is often found in the elderly when cells age.

INTESTINAL STEM CELLS

The rapid turnover of cells in our digestive tract is due to the high concentration of stem cells there. If those stem cells become senescent, the digestive tract’s ability to recover is impaired.

SATELLITE CELLS

The population of muscle stem cells (“satellite cells”), is relatively small, despite the fact that they’re responsible for muscle growth and repair. In addition to reducing in number as we age, satellite cells tend to produce more fibrous tissue versus muscle tissue and it is this loss of satellite cell function, not actual muscle, that is likely responsible for reduced recovery and shrinking muscle size as we age.

NERVE CELLS

Luckily for us, the satellite nerve cell decline is resistant to many stressors. In this way, brain and neurological function is maintained; however, when senescence does strike, numbers reduce rapidly, leading to impaired memory and learning – hence the cognitive defects commonly seen in older individuals.

FAT STEM CELLS

White fat (“adipose tissue”) found around our organs is susceptible to senescence thanks to its high concentration of cortisol receptors. These stem cells lose their ability to divide properly until they no longer divide at all and simply enlarge. Once they reach a certain size, breakdown results in inflammation and water retention.

SKIN STEM CELLS

Skin stem cells are divided into categories with some responsible for hair growth such as hair follicle stem cells, and melanocyte-producing stem cells. Hair follicle stem cells don’t decline in number as we age even though hair loss is so common. It’s the loss of function that is responsible. Unlike hair follicle stem cells, the number of melanocyte stem cells rapidly declines with age.

HOW CAN WE PUT THIS WHOLE PROCESS INTO REVERSE?

In lieu of connecting your arteries with that of someone younger, there are a few steps we can take to prevent stem cells from becoming senescent, and for eliminating those that have.

REDUCE OUR SENESCENCE BURDEN

Senescent cells must be eliminated in order to prevent the damage they do and to protect nearby cells. Research has shown that fasting for 18 to 24 hours induces autophagy, the process used to recycle old proteins, damaged cells, and abnormal components of cellular checkpoints. When our body enters a state of autophagy, damaged cells and components are eliminated.

Various foods can also stimulate autophagy. These include:

• Green tea

• Coffee

• Ginger

• Curcumin

• Omega 3 fatty acids

• Berries

PREVENT OUR CELLS FROM BECOMING SENESCENT

Sympathetic or fight-or-flight dominance brought on by stress causes the release of cortisol from the adrenal glands. Excessive or prolonged exposure to cortisol will lead to the breakdown of cells and their components, but we can counter this by entering a state of rest and digest (“parasympathetic dominance”).

Try these techniques:

• Resonant frequency breathing (six breaths per minute)

• Avoid loud music

• Inhale lavender oil through a diffuser

• Walk in nature

• Take a panoramic view of artwork

• No more than three servings per day of processed foods

EXERCISE MORE

In addition to putting our body into a state of rest and digest, we can increase our capacity to deal with stress before the negative effects kick in. Moderate exercise for 150 minutes a week or intense exercise for 75 minutes a week will help.