Part VII of Oxidative Stress and Recovery: Mitochondrial Damage
This series of articles is based on the premise that the lack of progress in recovering lost health is due to a sustained level of oxidative stress that our body is unable to manage. Unmanaged oxidative stress keeps our bodies in turmoil. In this condition, our body's defenses are in retreat and we are fighting with a rear guard action. If we are unable to hold our ground, we are not able to maintain or achieve homeodynamics/homeostasis. Even a weak body that has reached homeodynamics, can begin getting well and taking back the ground it lost. In previous issues, I listed seven areas of oxidative stress that are primary offenders. The area this article will focus on is oxidative stress to the mitochondrion. In particular, mitochondrial damage (myopathy) from continued xenobiotic exposure (exogenous and endogenous) . This can come from exposure to neurotoxins like mercury and to continued exposure from what is stored in the body's tissue.
Mitochondrion
Every cell in the body contains hundreds of mitochondria--"electric power company" of cells. A single mitochondria contains several DNA loops, each of which includes 37 genes involved in energy generation. The DNA in the mitochondrion is completely different from the DNA in the cell nucleus. It does not have the same repair or protective mechanisms. In fact, it is 2000 times more likely to suffer permanent damage than the DNA in the cell nucleus. Mitochondrial DNA are inherited exclusively from the mother--genetic defects included. You are essentially more your mother than your father due to this inheritance of mitochondrial genes. The mitochondrion provide 90 per cent of the energy that cells with which tissues, organs, and the body as a whole need to function. Mitochondrial energy production is the foundation for good health and wellbeing. It is necessary for strength, stamina and consciousness. Even subtle deficits in mitochondrial function can cause weakness, fatigue and cognitive difficulties.
Mitochondrial Damage.
The mitochondria generate energy through a complicated process (oxidative phosphorylation) that involves the relay of electrons along a series of protein complexes (called the respiratory chain). This respiratory chain allows energy carrying molecules (ATP being the major one) to be synthesized from the food (fuel) we eat and the oxygen we breath. It also produces endogenous toxins called Reactive Oxygen Species (ROS). ROS are responsible for the damage the mitochondrial DNA incur. This is sometimes called the Oxygen Paradox.
Obviously, anything that is able to compromise ATP production could harm or kill cells and thereby cause organs to malfunction and clinical symptoms to develop. Tissues and organs most easily affected by decrease ATP production (low energy) are high energy requiring cells such as those found in the central nervous system followed by the heart and skeletal muscle, the kidneys and hormone-producing tissues.
Several factors could cause mitochondrial energy production to decline with age even in people who start off with healthy mitochondria and nuclear DNA. Long-term exposure to metal toxins such as mercury is one. Many of the most potent toxins work their mischief by inhibiting the mitochondria. Another factor could be life long accumulation of somatic mitochondrial DNA mutations.
Mitochondrial Preservation
Mutations and toxin inhibition of ATP synthesis forms the basis for the "mitochondrial theory of aging". Research evidence suggests that the activity of the respiratory chain complex falls with age in the brain, skeletal muscles and heart. If free-radical damage does indeed drive the accumulation of somatic mitochondrial DNA mutations and thus influence the speed of aging, then treatments that block mitochondrial production of free-radicals (ROS) and thereby protect mitochondrial DNA could potentially slow aging and delay the onset of age-related diseases. Such approaches could perhaps consist of lifelong treatment with antioxidants. "The combination of antioxidants such as vitamin E (particularly the mixed alpha, beta, gamma, and the delta tocopherols) coenzyme Q10, and lipoic acid seems to emerge as an important protector of mitochondrial function in tissues that are shifted toward oxidative stress as a consequence of proinflammatory reactive proteins or glycosylated proteins." Additional nutrients that support the respiratory chain further protect and up-regulate energy production. Caloric restriction studies have suggested that supplementation with antioxidants alone may not be enough to prevent damage; but, when combined with calorie restriction there appears to be a synergistic or enhanced effect. Also the type and quality of foods consumed are important as in the old adage "you are what you eat"
Action Plan
The weight of knowledge regarding the mitochondria and energy production is growing exponentially. The body of information suggest that life-style, quality and quantity of food, exercise and protection from ROS are important. Using an approach that includes all these factors is essential in protecting the mitochondrion and up-regulating its energy production. Prudence suggests that extremes in this approach such as using mega-amounts of antioxidants could be counter productive.
Suggested Reading
I recommend the book "The Road to Immunity: How to Survive and Thrive in a Toxic World" by Kenneth Bock, M.D., and Nellie Sabin. This book covers a broad range of environmental challenges to healthy living. It contains 426 pages of easy to understand but densely packed information. You can order this book here.