Martin Picard, Columbia University
Abstract: In addition to producing energy, mitochondria perform a number of biochemical and signaling functions. Recent evidence suggests that, like neurons in neural networks, mitochondria sense, integrate, and signal. Mitochondria thereby transmit information about external stressors and translate it into specific molecular and physiological responses. To understand how this influences gene expression and multisystemic neuroendocrine responses to psychological stress, we have genetically manipulated different mitochondrial functions in cells and mice. This work shows that mitochondria regulate the nature and magnitude of cellular and systemic stress responses. Studies in tissues of patients with mitochondrial DNA diseases also reveal the existence of novel mitochondrial structures – mitochondrial nanotunnels – that enhance communication between mitochondria. To understand the influence of psychological states on mitochondria, we have developed the mitochondrial health index (MHI), and found that positive and negative mood are associated with MHI on subsequent days. Together, these preliminary studies provide converging evidence that mitochondrial signaling plays an unsuspected role as an interface between psychological (brain) and physiological (body) processes.