Mitochondrial dysfunction underlies depression, bipolar disorder, and schizophrenia.

Chronic stress damages mitochondria, impairing neuroplasticity and driving treatment-resistant depression.

Mitochondria travel through the blood and communicate signals between cells.

For decades, psychiatry has focused on neurotransmitters. Depression was a serotonin problem. Schizophrenia was a dopamine problem. Bipolar disorder was a mood stabilizer problem. This concept, while clinically useful, has always been incomplete. Now research suggests we may have been looking at the wrong part of the cell. The mitochondrion, which is often described as "the powerhouse of the cell," turns out to be a complex regulator of mood, cognition, stress resilience, and neuroplasticity. And it turns out that mitochondria don't always stay inside cells.

The Mitochondrion as Energy Producers

The human brain accounts for approximately 2% of the body’s weight but uses about 20% of the body's energy. Neurons are among the most energy-consuming cells in our body, and their survival depends on mitochondria. When mitochondria’s energy-producing efficiency decreases, the consequences are much more than just fatigue. Research has demonstrated that mitochondrial dysfunction occurs in major depressive disorder, bipolar disorder, and schizophrenia.

But, mitochondria control much more than energy production. They regulate calcium, initiate cell death (apoptosis), and produce reactive oxygen species (ROS). When ROS accumulate, they produce oxidative stress. This occurs during chronic psychological stress, and it destabilizes mitochondrial membranes. This impairs the neurons that regulate emotion, executive function, and social cognition. So, mental illness can be understood, at least in part, as a disease of the mitochondria.

Stress, the........

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