Mitochondria are organelle that live in our each of our cells, types of cells differ in the number of mitochondria they house. Mitochondria are the powerhouse of the cell, responsible for making energy for us to carry out our bodily processes through the production of adenosine triphosphate or ATP. Mitochondria consume about 90% of oxygen used in the body in this process. Our brain consumes a relatively large amount of the ATP we make, 22-25%! Fats, proteins, and carbohydrates, our macronutrients, are the necessary substrates that power the pathways that that ultimately produce ATP within the mitochondria.
When we think of mitochondrial dysfunction we can think of “brain, pain, and drain”. Some disorders that stem from improper mitochondria function include Alzheimer’s, depression, autism, headaches, fatigue, neurodegeneration, memory loss, anxiety, and other mood orders. Some mitochondrial dysfunctions are from being born with a genetic abnormalityand are easy to identify. This is classified as primary dysfunction is relatively rare. However, some are due environmental events in our lives that challenge our mitochondrial health, these are classified as secondary mitochondrial diseases. This category makes up a much greater percentage of the population and come from deficiencies or excess of chemicals involved in the process, or are due to exposures to medications, environmental toxins, and heavy metals.
When we have a decrease in energy, we have an increase in oxidative stress and free radicals. Small amounts of oxidative stress are beneficial to the body and triggers our adaptation response. This signals the body to initiate DNA repair, create new tissues and neurons. When the body is overwhelmed and there is too much to repair, we get into problems and are unable to adapt. Often this can lead to a delay in determining if there is mitochondrial dysfunction because it can take a little while for the body to be tipped over to the point of overwhelmed.
Mitochondria also play a role is determining whether the entire cell lives or dies. This can occur when there is excess oxidative stress to the mitochondria. Mitochondria are directly involved in activation or suppression of genetic pathways to activate enzymes that deal with apoptosis (cell death). The state of health of the mitochondria plays a large role in whether the cell lives or dies. When we protect the mitochondria functionality there is a reduced risk of cell apoptosis.
When we focus providing an environment that protects mitochondrial healthy, we are protecting the brain against many neurogenetic diseases. This is also the same process used once we have one of these conditions that have already arisen to restore our mitochondrial health. Insult to the mitochondria include inflammation. When our brain is inflamed our mitochondria become dysfunctional.
When we think of things that are good for mitochondria, they often correlate with things that are good for our cognition. This includes appropriate exercise and appropriate calorie restriction. Aerobic exercise has led to an increase in size of the hippocampus, responsible for memory. this turns on the gene that is responsible for brain derived neurotropic factor, responsible for neurogenesis. This is no pharmacologic intervention that can do this.
On the other hand, sedentary lifestyle, diabetes, obesity, high cholesterol, and exposure to toxins, the body will not be able to adapt to the stress and this will lead to inflammation which leads to even more oxidative stress and perpetuates the cycle. High inflammation decreases neuroplasticity, synaptic plasticity, and can lead to neuro degeneration.
Brain events are very connected to the gut. The permeability or “leaky gut” has a large role in inflammation throughout or whole body and especially brain. This is a result of components from our digestive track making their way into out systemic circulation. When this happens, it initiates in immune response and ultimately leads to the production of cytokines. Cytokines can damage mitochondria and lead to cell death. Our brain health is closely connected on events occurring in the gut.
This gives us the opportunity to use lifestyle choices powerfully influence our gut health. Diets that higher in sugars and carbohydrates and lower in fat and fiber, favor a change in the epigenetic modulators. Our food choices influence our gut microbiome and can lead to major in the modulators that affect many processes.