Histamine stimulates thermogenesis of brown and beige fat / 生理学报

β3-adrenergic agonists induce adaptive thermogenesis and promote beiging of white fat. However, it remains unclear which metabolites mediate the stimulatory effects of β3-adrenergic agonists on thermogenesis of brown and beige fat. In this study, adipose tissue was isolated from 8-week-old C57/BL6J male mice by intraperitoneal administration of β3-adrenergic agonist CL316,243 for RNA-Seq, which revealed that histidine decarboxylase, a key enzyme in histamine synthesis, was strongly induced in adipose by CL316,243. Therefore, we speculated that histamine might be involved in the process of thermogenesis in adipose tissue. We determined the physiological role and mechanism by which histamine promotes fat thermogenesis by intravenous administering histamine to C57BL/6J mice fed a normal or a high-fat diet. The results showed that intravenous injection of histamine into C57BL/6J mice fed a normal diet stimulated the expression of thermogenic genes, including peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) and uncoupling protein 1 (UCP1), in brown adipose tissue (BAT) and inguinal white adipose tissue (iWAT). H&E staining also suggested that histamine treatment decreased the size of lipid droplets in adipocytes. Moreover, histamine treatment also enhanced thermogenesis of fat in high-fat diet induced obese mice, and improved glucose intolerance and fatty liver phenotype. Finally, we demonstrated that the effects of histamine on the thermogenic program were cell autonomous. Our data suggest that histamine may mediate the effects of β3-adrenergic agonists on thermogenesis of fat.

[Comparison of moderate and high volume aerobic training on gene expression of uncoupling protein 1 [UCP-1] in subcutaneous white adipose tissue of wistar rats]

Introduction: The aim of this study was to investigate the effect of moderate and high volume aerobic training on the expression of Uncoupling Protein 1[UCP-1] gene in subcutaneous WAT [sub-WAT]

Materials and Methods: Twenty-four rats were assigned randomly into three groups: 1] control [n=8] 2] moderate-volume aerobic training [n=8] and 3] high-volume aerobic training [n=8]. Subjects of training groups underwent continuous aerobic training on the treadmill for 8 weeks, 5 sessions per week at two different volumes of training. The Real Time-PCR method was used to measure the expression ratio of UCP-1 gene

Results: Data showed that although the expression ratio of UCP1 gene in the moderate volume aerobic training group was significantly higher than control group [P=0.014], its expression ratio in the high volume aerobic training group did not differ significantly from controls [P=0.36]; neither was the gene expression ratio different between moderate and high volume aerobic training groups [P=0.59]

Conclusion: Results indicate that moderate volume aerobic training, had an obvious effect in inducing UCP1 gene expression in subcutaneous adipose tissue, while the high volume aerobic training did not. Thus, increasing the volume of aerobic training to high levels may not be a key factor in promoting the non-shivering theremogenesis of sub-WAT