The glucose metabolism reprogramming of yak Sertoli cells under hypoxia is regulated by autophagy

Hypoxia often has negative effects on testis development and spermatogenesis of mammals. Plateau yaks have lived in the hypoxia environment for generations, but have ensured testicular function, which is closely related to their unique hypoxia response mechanism. Glucose metabolic reprogramming is an important way for cells to respond to stressful environments, especially the metabolite lactate, which is the energy basis for the development and differentiation of germ cells. In this study, hypoxia (5% O₂) effectively promoted yak Sertoli cell proliferation and decreased autophagy and apoptosis. It was found that the cells showed good hypoxic adaptation. Metabolomics results showed that glucose metabolism was enhanced in yak Sertoli cells in response to hypoxia, and 13 glucose metabolites were increased, including the production and transport level of lactic acid (LA), which may have changed the pentose phosphate metabolic pathway of cells, these changes are conducive to support the glucose metabolism balance of cells under hypoxia. Crucially, when autophagy is activated under hypoxia, GLUT3, GLUT8, and MCT4 proteins are degraded, while GLUT1 and MCT1 are not affected, suggesting that autophagy may achieve glucose metabolic reprogramming by selectively regulating the expression of functional factors of glucose metabolism, which is conducive to energy intake and spermatogenesis in testis of yaks.