Effect of Treadmill Running on MSTN and ActRⅡB Gene Expressions in Adipose Tissue of Obese Rats
(2.East China Normal University, Shanghai, China 200241)
【Abstract】Objective: The purpose of this study was to observe the effects of treadmill exercise on myostatin (MSTN) signaling pathway of white adipose tissue (WAT) and brown adipose tissue (BAT) in obese rats induced by high-fat diet. Methods: Sixty male Wistar rats were randomly divided into control group with standard rodent chow and high-fat diet group with high-fat rodent chow. Sixteen normal rats and 16 obese rats were selected from those two groups after 8 weeks, and were randomly divided into sedentary control group (SC, n = 8), exercised control group (EC, n = 8), sedentary obese group (SO, n = 8) and exercised obese group (EO, n = 8). The rats in EC and EO groups underwent treadmill exercise 60 min per day, 5 days per week at the speed of 21 m/min, 8 weeks in total. Meanwhile, the rats in SC and SO groups underwent free running on the treadmill 60 min per day, 5 days per week at the speed of 0 m/min, 8 weeks in total. Body weight, TG, TC, HDL and LDL of rats were detected. And their WAT (perirenal, epididymal) and BAT were dissected and weighed. The mRNA expression levels of MSTN and ActRⅡB of the WAT and BAT were tested by RT-PCR. Results: 1) Compared with SC, the body weight of EC decreased significantly (P < 0.05) while the BAT weight and the HDL of EC increased (P < 0.01, P < 0.05); the body weight, WAT, TC, TG and LDL of SO significantly increased (Ps < 0.05), but the HDL of SO significantly decreased (P < 0.05). Compared with SO group, thr body weight, WAT weight and TG of EO significantly reduced (P < 0.05). 2) Compared with SC, the ActRⅡB in WAT of EC group decreased and the MSTN of SO group increased (Ps < 0.01), but both of them of EO decreased compared with those of SO (Ps < 0.01). Compared with SC, the MSTN in BAT of EC group increased but the ActRⅡB in BAT of EC and SO decreased (Ps < 0.01). Compared with SO, the MSTN and ActRⅡB of EO increased (Ps < 0.01). Conclusion: The effect of eight weeks of treadmill exercise on WAT and BAT weights of obese rats induced by high-fat diet may be because of MSTN signaling pathway.
【Keywords】 treadmill exercise; obese; white adipose tissue; brown adipose tissue; myostatin signaling pathway;
(Translated by PXJ1)
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