低温环境下禁食对小鼠自发运动及腓肠肌中PGC-lα、ERRα表达的影响

Effects of fasting on spontaneous activity and expression of PGC-lαand ERRαin gastrocnemius muscle of mice under low ambient temperature

应用旷场试验测定不同时长4℃冷暴露下采食和禁食C57BL/6小鼠的自发运动,并结合骨骼肌中PGC-lα与ERRα表达水平,探讨低温环境下禁食对C57BL/6小鼠自发运动的影响。结果显示,低温环境下禁食对C57BL/6小鼠的自发运动并无显著性影响,但焦虑情绪12 h差异显著(P<0.05),探索行为8 h和12 h差异极显著(P<0.01);腓肠肌中PGC-1α表达在4,8 h时差异极显著(P<0.01),12 h差异显著(P<0.05);ERRα表达在4,6 h时差异极显著(P<0.01)。结果表明,低温环境下禁食对C57BL/6小鼠自发运动未出现明显影响,而对小鼠焦虑情绪、探索行为和腓肠肌中PGC-lα、ERRα表达存在不同程度的影响,相比于禁食而言,冷刺激对小鼠机体的影响更大。

One of the most common stressors endured by free-living animals are reductions in food availability which can occur due to inclement weather.It is undoubtedly a serious challenge for animals to cope with the dual effects of food shortage and environmental disturbance.Therefore,the purpose of this study was to investigate the effect of short-term fasting on spontaneous activity of C57 BL/6 mice under low ambient temperature.Open field test was used to determine the spontaneous activity of C57 BL/6 mice in the feeding and fasting groups under cold exposure at 4℃for different time lengths.After the test,the mice were euthanized immediately and gastrocnemius muscle was collected.The expression of PGC-lαand ERRαin gastrocnemius muscle was determined by Western blot analysis.The results of open field test showed that there was no significant difference in spontaneous activity between feeding and fasting mice.However,there were significant differences in exploratory behavior between feeding and fasting mice when the cold stimulus lasted 8 h and 12 h.There was significant difference in anxiety between feeding and fasting mice at 12 h of cold stimulation.The expression of PGC-1αin gastrocnemius muscle were significantly different at 4,8,12 h of cold stimulation.And the expression of ERRαwere significantly different between the two groups at the 4 h and 6 h.This study showed that short-term fasting at low ambient temperature had no significant effect on spontaneous activity of C57 BL/6 mice,but had different effects on anxiety,exploratory behavior and expression of PGC-lαand ERRαin gastrocnemius muscle of mice,indicating that compared with short-term fasting,cold stimulation had greater effect on mice.