PGC-1β modulates the expression of genes involved in mitochondrial function and adipogenesis during preadipocyte differentiation.

This study determined the expression of genes involved in mitochondrial function and adipogenesis at mRNA and protein levels by transfecting rat differentiating preadipocytes with siRNA/Lipofectamine complex and pcDNA-PGC-1β (peroxisome proliferator-activated receptor-γ coactivator-1β)/Lipofectamine complex, respectively, to further elucidate the role of PGC-1β in white preadipocyte differentiation. The results showed that the transfection of PGC-1β siRNA inhibited the expressions of mitochondrial genes malate dehydrogenase, carnitine palmitoyltransferase 1, nuclear respiratory factor 1, ATP synthesis, adipocyte differentiation key transcription factor peroxisome proliferator-activated receptor-γ, sterol regulatory element binding protein 1c and fatty acid synthetase, whereas the triglyceride synthesis was retarded (p < 0.05). Furthermore, overexpression of PGC-1β up-regulated the expressions of adipogenic and mitochondrial biosynthetic marker genes and promoted triglyceride accumulation during 3T3-L1 adipocyte differentiation. These observations suggest that PGC-1β modulates the expression of mitochondrial function and adipogenesis-related genes and affects white preadipocyte differentiation.