Effect of EPO on PRDM16, FGF21 expression and STAT phosphorylation of brown adipose tissue in HFD mice

doi:10.12047/j.cjap.5654.2018.068

Abstract

Abstract: Objective: To investigate the effect of erythropoietin (EPO) on blood glucoseand plasma insulin level, index of insulin resistance (HOMA-IR), introperitoneal glucose tolerance test (IPGTT), the mRNA and protein level of PR domain-containing 16 (PRDM16), phosphorylated signal transducer and activator of transcription 3 (p-STAT3), fibroblast growth factor 21 (FGF21) of brown adipose tissue (BAT) in mice fed with high fat diet (HFD) in order to provide clues for the mechanism of obesity and complication.Methods: Twenty C57BL/6J male mice fed with HFD were randomly divided into control group (HFD-Con) and EPO group (HFD-EPO), mice in the two groups were injected intraperitoneally normal saline and EPO (200 IU/kg) res pectively, 3 times per week for consecutive 4 weeks.Then the body weight, blood glucose, plasma insulin level, HOMA-IR and IPGTT were detected.The mRNA and protein level of PRDM16, FGF21, p-STAT3/STAT3 in brown adipose tissue were detected by real-time quantitative RT-PCR and Western blot respectively.Results: After intraperitoneal injection of EPO for 4 weeks, the body weight of the mice in HFD-EPO and HFD-Con groups was (26.65±0.85) g and (31.50±1.6 0) g respectively.The blood glucose of the mice in HFD-EPO group[(62.79±8.09) mg/dl]was significantly decreased compared with that in HFD-Con group[(91.06±9.86) mg/dl].The plasmainsulin level in HFD-EPO group[(10.56±1.06)μU/ml]was significantly decreased compared with that in HFD-Con group[(13.2±1.1)μU/ml, P< 0.01].The level of IPGTT in HFD-EPO group was significantly ameliorated and th e HOMA-IR decreased compared with those in HFD-Con group.The mRNA and protein expressions of PRDM16, FGF21 and the level of STAT3 of brown adipose tissue in HFD-E PO group were increased obviously.And there was no difference of FGF21 mRNA content in liver and FGF21 content in plasmabetween the two groups.Conclusion: EPO could promote differentiation of brown adipose tissue by increase in the express ion of PRDM16, and decrease the blood glucose level, ameliorate glucose metabolism in obses mice.

Key words: high fat diet, brown adipose tissue, erythropoietin, PR domain containing 16, phosphorylated signal transducer and activator of transcription 3, fibroblast growth factor 21

ZHANG Rui, CHEN Lu, GE Jun-mei, MA Gen-shan, CAI Jun-yan. Effect of EPO on PRDM16, FGF21 expression and STAT phosphorylation of brown adipose tissue in HFD mice[J]. CJAP, 2018, 34(4): 294-298.

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