By Dr. Frank Sabatino

The dance of life and death within the body is a many splendored thing. All cells go through relentless rituals of birth, growth, death,  nutrient intake, waste elimination, damage, repair, and metabolic activity that maintains/balances all body systems and functions. Since all these processes require energy, it is imperative to have enough usable energy for cellular function. In every one of the trillions of body cells, there are energy factories, power stations, called mitochondria that orchestrate cellular energy production. In fact, there is a direct correlation between the energy demands of cells and the amount of mitochondria they contain. Muscle (especially heart muscle), brain and liver cells are the most active, energy-demanding cells of the body, and can have several thousand mitochondria per cell.

Mitochondria are an integral player in a wide variety of cellular functions, including the unique cell cycle of energy production, special uptake and regulation of calcium signals in cells, and the activation and regulation of normal cell death referred to as apoptosis. Damage and dysfunction of mitochondria are associated with metabolic and age-related disorders, premature aging, neurodegenerative disease, and ischemic injury to the heart and brain caused by blood vessel damage that restricts blood and oxygen supply to these vital organs. (1) (2) (3)

This process of energy transformation in the mitochondria is a very sophisticated electrochemical process called oxidative phosphorylation that converts the food you eat, in the presence of the oxygen you breath,  into available, usable energy.

Mitochondria house the major enzyme and protein components that process (oxidize) the building blocks of plant sugars, proteins and fats,  in the presence of oxygen, into usable energy contained in the high-energy compound ATP. This process involves a pathway of cellular respiration (the citric acid cycle), and a chain of proteins and enzymes in the inner membrane of the mitochondria (the respiratory/electron transport chain), that generates and moves electrons and protons to create an electrical potential, like a battery, to power the formation of ATP. (4) The mitochondria is in constant communication with other parts of the cell to balance energy demand with production.

This communication is regulated by the signaling, uptake, and  availability of calcium in the mitochondria. An increase in calcium in the mitochondria is a major signal for an increased demand and production of energy. This is especially important for the most active cells in the body performing relentless functions that are the most energy demanding, including the contraction and activity of cells in muscles/heart, and the electrical excitability of nerve cells that release neurotransmitters in brain. (5)(6)

It is important to realize that all cells have a natural lifespan. Cells are constantly being born, living and dying. Red blood cells typically live about 120 days while other cells can only live a few short hours or days. The natural, programmed death of cells is called apoptosis and is regulated to a great extent by mitochondria. Some have referred to the mitochondria as the gatekeeper of cell death, and a poison cabinet, due to key proteins that are released from the inner membrane and matrix of the mitochondria that initiate apoptotic cell death. (1) The protein cytochrome c, an essential part of the respiratory chain, is a major initiator of apoptosis when it is released from the inner membrane of the mitochondria. (7) As cells age and approach death, structural changes occur in mitochondria that promote the removal of aged and damaged mitochondria via a specialized form of autophagy called mitophagy. (8) This ensures that defective mitochondria can be broken down into smaller parts, so their content can be easily degraded and recycled by the cell. 

Since oxygen is required for optimal energy production by the mitochondria, the use and turnover of oxygen also results in the production of very reactive, unstable oxygen by-products called free radicals (superoxide radicals). These reactive forms of oxygen are oxidants that are associated with oxidative damage and disease. However, the mitochondria has evolved the ability to produce and transport antioxidants including Superoxide Dismutase ( SOD), Coenzyme Q10, and Glutathione to protect itself against free radical damage. But there are a variety of food, lifestyle (smoking) and environmental factors (air pollution, herbicides and pesticides in food) that can significantly increase free radicals beyond the amount of antioxidants you have available for your protection, creating dangerous oxidative stress. (9) This chemical stress is fundamental to most disease processes and is significantly implicated in cardiovascular disease, diabetes, neurodegenerative disease, cancer, aging.

Animal products and ultra-processed foods significantly increase free radicals, oxidative stress, and damage to mitochondria. Meat, French fries and foods processed with, milk, cheese, butter and eggs produce significant amounts of the oxidized free-radical form of cholesterol associated with damage to blood vessels, and vascular blockage diseases in the heart and brain. (10) Compared to plant protein, the essential amino acid methionine is extremely high in eggs, meat and fish. Excess methionine increases the production of reactive oxygen free radicals in the mitochondria, increases oxidative stress, and decreases longevity. (11) A whole-food, plant-exclusive diet provides significantly more antioxidants, including flavonoids, vitamin C, vitamin E etc., than any other eating plan, reducing oxidative stress in mitochondria. Keep in mind that the antioxidants in plant food are contained in the colors of fruits and vegetables. So just put a rainbow on your plate every chance you get.

Chronic sleep deficiency promotes dysfunction of mitochondria, and increases the production of reactive oxygen free radicals and oxidative stress. Lack of sleep impairs the movement and current of electrons flowing in the inner mitochondrial membrane that powers energy production, reducing energy output and increasing fatigue at a cellular level. (12) So it is imperative to enhance your quality and quantity of restorative sleep to support your mitochondria, and improve and maintain your overall energy level. Chronic stress can promote mitochondrial damage and dysfunction that interferes with the production of ATP. The resulting cellular fatigue promotes inflammation, oxidative stress, and accelerated aging. (13) Minimizing the stressful events of your life, and participating in mindful stress reduction techniques, can significantly increase your production and reserve of available energy and reduce fatigue. 

It is also important to consider the connection between your muscles and mitochondria for effective energy production. As I previously stated, muscles are one of the most active parts of the body, and have thousands of mitochondria in each muscle cell to meet their high energy demands. Unfortunately, their is often a significant loss of muscle mass with age (sarcopenia). When you lose muscle mass, you lose the mitochondrial energy factories that they contain, and can experience a dramatic loss of energy and debilitating fatigue. So it is imperative to participate in a combination of endurance activity and resistance (weight) training on a regular basis, especially as you get older, to improve muscle mass, increase the number of mitochondria and promote sustained, enhanced energy production. 

If you are dealing with chronic disease or disturbing fatigue, embrace the food and lifestyle factors that reduce oxidative stress, and support the integrity and function of your mighty mitochondria for enhanced energy production.

REFERENCES

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