Department of Physiology, LSU Health Sciences Center, New Orleans, LA 70112, United States of America.
Joint Diabetes, Endocrinology & Metabolism Program, Pennington Biomedical Research Center, Baton Rouge, LA 70808, United States of America.
Life Sci. 2021 May 15;273:119290. doi: 10.1016/j.lfs.2021.119290. Epub 2021 Mar 1.
The current study examined the role of sex differences in the development of risk factors associated with obesity and its comorbidities using models that differ in their susceptibility to develop obesity, obesity-resistant S5B/Pl (S5B) and obesity-prone Osborne-Mendel (OM) rats. Male and female rats were fed a low fat or high fat diet (HFD) and markers of metabolic syndrome (MetSyn) and expression of inflammatory cytokines/chemokines in visceral and subcutaneous adipose depots were measured. We hypothesized that male and female OM and S5B rats would exhibit differential responses to the consumption of HFD and that females, regardless of susceptibility to develop obesity, would display decreased obesity-related risk factors. Results suggested that consumption of HFD increased adiposity and fasting glucose levels in male OM and S5B rats, decreased circulating adiponectin levels in male S5B rats, and increased body weight and triglyceride levels in male OM rats. The consumption of HFD increased body weight and adiposity in female OM rats, not female S5B rats. Overall, female rats did not meet criteria for MetSyn, while male rats consuming HFD met criteria for MetSyn. Visceral and subcutaneous adipose tissue inflammation was higher in male rats. In visceral adipose tissue, HFD consumption differentially altered expression of cytokines in male and female S5B and OM rats. These findings suggest that resistance to obesity in males may be overridden by chronic consumption of HFD and lead to increased risk for development of obesity-related comorbidities, while female rats appear to be protected from the adverse effects of HFD consumption.
本研究使用易患肥胖、肥胖抗性 S5B/Pl（S5B）和肥胖易感 Osborne-Mendel（OM）大鼠的不同模型，研究了性别差异在与肥胖及其合并症相关的风险因素发展中的作用。雄性和雌性大鼠分别给予低脂或高脂饮食（HFD），并测量代谢综合征（MetSyn）标志物和内脏及皮下脂肪组织中炎症细胞因子/趋化因子的表达。我们假设雄性和雌性 OM 和 S5B 大鼠对 HFD 的摄入会有不同的反应，并且无论是否易患肥胖，雌性大鼠都会表现出较少的肥胖相关风险因素。结果表明，HFD 的摄入增加了雄性 OM 和 S5B 大鼠的肥胖和空腹血糖水平，降低了雄性 S5B 大鼠的循环脂联素水平，增加了雄性 OM 大鼠的体重和甘油三酯水平。HFD 的摄入增加了雌性 OM 大鼠的体重和肥胖，但不增加雌性 S5B 大鼠的体重和肥胖。总体而言，雌性大鼠不符合 MetSyn 标准，而摄入 HFD 的雄性大鼠符合 MetSyn 标准。雄性大鼠的内脏和皮下脂肪组织炎症水平更高。在内脏脂肪组织中，HFD 的摄入改变了雄性和雌性 S5B 和 OM 大鼠细胞因子的表达。这些发现表明，雄性对肥胖的抵抗力可能被 HFD 的慢性摄入所克服，并导致肥胖相关合并症发生的风险增加，而雌性大鼠似乎免受 HFD 摄入的不良影响。
