OXPHOS-Arachidonic acid-PPAR signalosome controls brown adipocyte peroxisomal function.

Brown adipose tissue plays a crucial role in modulating whole-body energy expenditure through the thermogenic function of its mitochondrial respiratory chain. Pharmacological interventions targeting this function hold significant therapeutic promise. Thus, gaining a comprehensive understanding of the pathophysiological regulation of brown adipose tissue is imperative for future therapeutic applications. In this study, we investigated the metabolic mechanisms underlying the regulation of mature brown adipocyte function by the mitochondrial respiratory chain. Our findings indicate that deficiency in mitochondrial complex I in mature brown adipocytes leads to lipidomic remodeling. This remodeling results in an increase in arachidonic acid content and prostaglandin E2 (PGE2) production, leading to reduced transcriptional activity of peroxisome proliferator-activated receptor gamma (PPARγ) and peroxisome proliferator-activated receptor alpha (PPARα) and alterations in the content of PPAR activator complexes, which consequently result in reduced brown adipocyte thermogenesis and peroxisomal gene expression in mature brown adipocyte. In summary, our study elucidates that the mitochondrial-derived arachidonic acid signal regulates brown adipocyte thermogenesis and peroxisome biogenesis by modulating the PPAR activator complex."