The Effect Of Leptin On Pre-adipocytes Differentiation And Browning Through Hedgehog Signaling Pathway

Leptin is a protein hormone secreted by adipocytes,has extensive biological effects,it promotes the body’s energy consumption,so predicted that leptin is invovled in the white adipose tissue browning.And white adipose tissue browning is a research hotspot in recent years,it has a function to regulate the body’s metabolism and energy balance,which provide metabolic diseases such as obesity,diabetes treatment with new ideas,thus to explore the Leptin role on white adipose tissue browning has great significance.Another Hedgehog(Hh)signaling pathway play an important role in embryonic development,the role of the white adipose tissue browning is more controversial,explore its action on the white adipose tissue browning has great significance.In this study,Hh inhibitor Cyclopamine(Cy)and activator Purmorphamine(Pu)and Leptin was used to treat mice pre-adipocytes in vitro.The size of lipid droplets in the cells was observed by staining.The expression of adipogenesis differentiation marker genes,brown adipose and mitochondria marker genes and Hh signaling pathway marker genes were detected by RT-qPCR and WB;In vivo,Leptin injection was performed on high-fat obese mice to measure various physiological indices of mice.HE staining was used to observe cell size in each tissue.RT-qPCR and WB were used to detect the expression of cell adipogenesis differentiation marker genes,brown fat and mitochondria marker genes and Hh signaling pathway marker genes,and obtained the following main innovative results:1.Cy make the small lipid droplets increased in adipocytes,the RT-qPCR and WB results show that the adipogenesis marker gene,brown adipose and mitochondria marker gene expression are on the rise significantly(P<0.05,P<0.01).Pu inhibits the production of lipid droplets in cells and inhibits the adipose differentiation and browning.2.100 nmol/L concentration of Leptin make small lipid droplets,the RT-qPCR and WB results show that the adipogenesis marker gene,brown adipose and mitochondria marker gene expression are on the rise significantly(P<0.05,P<0.01).And Leptin inhibits the Gli1 expression significantly(P<0.01),it’s marker gene of the Hh pathway.3.The injection of high fat obese mice living Leptin(5 mg/kg/d)continued 7 d,found that Leptin significantly reduce the weight of iWAT,eWAT and BAT(P<0.05),HE showed lipid droplets decreased significantly,and the RT-qPCR and WB results show that the lipolysis and brown adipose marker gene expression were significantly decreased in iWAT,eWAT,BAT(P<0.05,P<0.01),and Leptin significantly inhibit the expression of Gli in iWAT(P<0.01).But the adipogenesis marker gene and brown adipose marker gene expression was significantly increased in Liver(P<0.01).In summary,the Hh signaling pathway inhibits the differentiation and browning of pre-adipocytes in mice.Leptin promotes the differentiation and browning of pre-adipocytes by inhibiting the Hh signaling pathway in mice.Leptin inhibit the adipogenesis,lipolysis and browning of adipose tissue,improve the occurrence of diet-induced obesity.The above results provide the basis for further investigation of Leptin regulation on the mechanism of white adipose tissue browning.