性别差异对小鼠体重体脂影响的研究

Effect of sex difference on body weight and body fat in mice

目的探讨性别差异对小鼠体重及体脂的影响。方法使用77只FVB/NJ背景小鼠模型,分为雄性小鼠和雌性小鼠,分别在3~8周龄每周测量1次体重,采用小动物核磁共振谱仪检测小鼠体脂含量,糖耐量实验和胰岛素耐量实验评估糖代谢情况,能量代谢实验记录小鼠的氧气消耗量、二氧化碳呼出量和能量消耗值。此外,在普通与高脂饮食条件下,分析雄性小鼠与雌性小鼠体重、体脂含量、糖代谢和胰岛素敏感性的差异。结果从4周龄开始,雄性小鼠体重明显高于雌性小鼠,脂肪/体重低于雌性小鼠,差异有统计意义(P<0.05)。雄性小鼠葡萄糖耐受程度[(694.8±129.4)mg·dL^(-1)·h^(-1) vs.(492.6±130.7)mg·dL^(-1)·h^(-1)]和胰岛素敏感度[(1008.4±137.0)mg·dL^(-1)·h^(-1) vs.(798.5±119.9)mg·dL^(-1)·h^(-1)]较雌性小鼠更差,差异有统计意义(P<0.05)。雄性小鼠的氧气消耗量[(1.60±0.12)mL·h^(-1)·g^(-1) vs.(1.47±0.08)mL·h^(-1)·g^(-1)]、二氧化碳呼出量[(1.40±0.06)mL·h^(-1)·g^(-1) vs.(1.33±0.08)mL·h^(-1)·g^(-1)]和能量消耗值[(0.49±0.04)kcal·h^(-1)·g^(-1) vs.(0.44±0.03)kcal·h^(-1)·g^(-1)]高于雌性小鼠,差异有统计意义(P<0.05)。短期高脂饮食,雄性小鼠体重明显高于雌性小鼠[(23.17±2.67)g vs.(17.96±0.78)g],差异有统计学意义(P<0.05),但体脂含量比较,差异无统计学意义(P>0.05)。结论性别差异明显影响小鼠体重和体脂含量,雄性小鼠在高脂饮食下容易生成更多脂肪。

Objective To investigate the effects of sex difference on the body weight and body fat in mice.Methods Seventy-seven FVB/NJ background mice models were used and divided into the male mice and female mice.The body weight was measured once a week at 3 to 8 weeks of age.The content of body fat in mice was detected by the small animal nuclear magnetic resonance spectrometer.The glucose metabolism was evaluated by the glucose tolerance test and insulin resistance test.The oxygen consumption,carbon dioxide exhalation volume and energy consumption of mice were recorded in the energy metabolism experiment.In addition,the differences in body weight,body fat content,glucose metabolism and insulin sensitivity under normal and high fat diet conditions between male mice and female mice were analyzed.Results Starting from 4 weeks of age,the body weight of male mice was significantly higher than that of female mice,while the fat/body weight ratio was lower than that of female mice,and the differences were statistically significant(P<0.05).The glucose tolerance degree[(694.8±129.4)mg·dL^(-1)·h^(-1) vs.(492.6±130.7)mg·dL^(-1)·h^(-1)]and insulin sensitivity[(1008.4±137.0)mg·dL^(-1)·h^(-1) vs.(798.5±119.9)mg·dL^(-1)·h^(-1)]in the male mice were worse than those in the female mice,and the differences were statistically significant(P<0.05).The oxygen consumption volume[(1.60±0.12)mL-1·h^(-1)·g^(-1) vs.(1.47±0.08)mL-1·h^(-1)·g^(-1)],carbon dioxide expiration volume[(1.40±0.06)mL-1·h^(-1)·g^(-1) vs.(1.33±0.08)mL-1·h^(-1)·g^(-1)]and energy consumption value[(0.49±0.04)kcal·h^(-1)·g^(-1) vs.(0.44±0.03)kcal·h^(-1)·g^(-1)]in the male mice were higher than those in the female mice,and the differences were statistically significant(P<0.05).In the short high lipid diet,the body weight in the male mice was significantly higher than that in the female mice[(23.17±2.67)g vs.(17.96±0.78)g],and the difference was statistically significant(P<0.05).But the body lipid content had statistical difference(P>0.05).Conclusion The sex differences significantly affect the body weight and body fat of mice,meanwhile the male mice are more likely to generate more fat under high fat diet.