Altered mitochondria-associated ER membranes (MAM) function shifts mitochondrial metabolism in amyotrophic lateral sclerosis (ALS)

Mitochondrial function is modulated by its functional interaction with the endoplasmic reticulum. Recent research indicates that these contacts are disrupted in familial models of amyotrophic lateral sclerosis. We report here this impairment in the crosstalk between mitochondria and the endoplasmic reticulum impedes the use of glucose-derived pyruvate as mitochondrial fuel, causing a shift to fatty acids to sustain energy production. Over time, this deficiency alters mitochondrial electron flow and the active/dormant status of complex I in spinal cord tissues, but not in the brain. These findings suggest MAM plays a crucial role in regulating cellular glucose metabolism and that its dysfunction may underlie the bioenergetic deficits observed in ALS.