Disruption of metabolic interactions between astrocytes and neurons, in particular of the lactate shuttle, may contribute to neurodevelopmental and psychiatric disorders such as autism spectrum disord Show more
Disruption of metabolic interactions between astrocytes and neurons, in particular of the lactate shuttle, may contribute to neurodevelopmental and psychiatric disorders such as autism spectrum disorder (ASD) and schizophrenia. The enzyme glycine decarboxylase (GLDC), predominantly expressed in astrocytes, degrades glycine and plays a critical role in regulating NMDA receptor function and cellular metabolism. Here, we investigated whether administration of lactate would reverse schizophrenia-like phenotypes in a mouse model for psychosis with 4 copies of the Gldc gene (4cG mice). Adult male and female 4cG and wildtype mice were subjected to acute L-lactate intraperitoneal administration one hour before behavioral testing and brain collection for biochemical assays. Y-maze spontaneous alternation test, prepulse inhibition of acoustic startle test, and the three-chamber social interaction test were performed for behavioral analysis, and Western blots for protein estimations. In 4cG mice, acute lactate administration one hour before assessment rescued short-term memory deficits, acoustic startle habituation deficits, and normalized deficits in social preference behavior. Furthermore, lactate treatment restored the expression of PGC1α, a master regulator of mitochondrial biogenesis, and brain-derived neurotrophic factor (BDNF), a protein essential for synaptic plasticity. The results suggest a role for astrocytic metabolism in modulating neuronal function, and potential molecular mechanisms underlying the reversal of behavioral phenotypes. The results indicate that exogenous lactate may reverse key pathophysiological and behavioral deficits in a mouse model for schizophrenia and that lactate supplementation may be useful as a therapeutic strategy for schizophrenia and related disorders. Show less