State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, People's Republic of China.
Comp Biochem Physiol A Mol Integr Physiol. 2010 Jan;155(1):25-33. doi: 10.1016/j.cbpa.2009.09.003. Epub 2009 Sep 11.
Immune defense is important for organisms' survival and fitness. Small mammals in temperate zone often face seasonal food shortages. Generally fasting can suppress immune function in laboratory rodents and little information is available for wild rodents. The present study tested the hypothesis that Mongolian gerbils (Meriones unguiculatus) could inhibit T cell-mediated immunity to adapt to acute fasting. Forty-two females were divided into the fed and fasted groups, in which the latter was deprived of food for 3days. After 66h fasting, half of the gerbils in each group were injected with phosphate buffered saline or phytohaemagglutinin (PHA) solution. T cell-mediated immunity assessed by PHA response was suppressed in the fasted gerbils compared with the fed gerbils. The fasted gerbils had lower body fat mass, wet and dry thymus mass, dry spleen mass, white blood cells, serum leptin and blood glucose concentrations, but higher corticosterone concentrations than those of the controls. Moreover, PHA response was positively correlated with body fat mass and serum leptin levels in the immunochallenged groups. Taken together, acute fasting leads to immunosuppression, which might be caused by low body fat mass and low serum leptin concentrations in female Mongolian gerbils.
免疫防御对于生物的生存和适应至关重要。温带地区的小型哺乳动物经常面临季节性食物短缺。一般来说，禁食可以抑制实验室啮齿动物的免疫功能，但对于野生啮齿动物的相关信息却很少。本研究检验了这样一个假设，即蒙古沙鼠（Meriones unguiculatus）可以抑制 T 细胞介导的免疫反应，以适应急性禁食。42 只雌性沙鼠被分为喂食组和禁食组，后者连续 3 天被剥夺食物。禁食 66 小时后，每组一半的沙鼠被注射磷酸盐缓冲盐水或植物血球凝集素（PHA）溶液。与喂食组相比，禁食组沙鼠的 T 细胞介导免疫反应（通过 PHA 反应评估）受到抑制。禁食组沙鼠的体脂质量、胸腺湿重和干重、脾脏干重、白细胞、血清瘦素和血糖浓度均较低，但皮质酮浓度较高。此外，在免疫挑战组中，PHA 反应与体脂质量和血清瘦素水平呈正相关。综上所述，急性禁食会导致免疫抑制，这可能是由于雌性蒙古沙鼠体脂质量和血清瘦素浓度降低所致。
