Delgadillo-Velázquez Jaime, Alday Efrain, Aguirre-García María Magdalena, Canett-Romero Rafael, Astiazaran-Garcia Humberto
Coordinación de Nutrición, Centro de Investigación en Alimentación y Desarrollo, Hermosillo, Mexico.
Departmento de Ciencias Químico-Biológicas, Universidad de Sonora, Hermosillo, Mexico.
Front Nutr. 2024 Jul 1;11:1387521. doi: 10.3389/fnut.2024.1387521. eCollection 2024.
Obesity is a complex disease that predisposes individuals to cardiometabolic alterations. It leads to adipose tissue (AT) dysfunction, which triggers insulin resistance (IR). This suggests that people with obesity develop local IR first and systemic IR later. AT secretes extracellular vesicles, which may be physiopathologically associated with the development of IR. Our aim was to evaluate the effect of a high-fat diet on different parameters of adiposity in a rat model of early-stage obesity and to determine if these parameters are associated with markers of systemic IR. In addition, we sought to explore the relationship between fasting blood measures of IR (Triglycerides/High Density Lipoprotein-cholesterol [TAG/HDL-c] and Triglycerides-Glucose Index [TyG Index]) with the size of adipocyte-derived extracellular vesicles (adEV).
We used a model of diet-induced obesity for ten weeks in Wistar rats exposed to a high-fat diet. Final weight gain was analyzed by Dual X-ray absorptiometry. Visceral obesity was measured as epididymal AT weight. IR was evaluated with fasting TyG Index & TAG/HDL-c, and adEV were isolated from mature adipocytes on ceiling culture.
In the high-fat diet group, glucose and triglyceride blood concentrations were higher in comparison to the control group (Log2FC, 0.5 and 1.5 times higher, respectively). The values for TyG Index and adEV size were different between the control animals and the high-fat diet group. Multiple linear regression analyses showed that adEV size can be significantly associated with the TyG Index value, when controlling for epididymal AT weight.
Our results show that lipid and glucose metabolism, as well as the size and zeta potential of adEV are already altered in early-stage obesity and that adEV size can be significantly associated with liver and systemic IR, estimated by TyG Index.
肥胖是一种复杂的疾病，使个体易患心脏代谢改变。它会导致脂肪组织（AT）功能障碍，进而引发胰岛素抵抗（IR）。这表明肥胖者先出现局部IR，随后出现全身IR。AT分泌细胞外囊泡，其可能在病理生理上与IR的发生有关。我们的目的是评估高脂饮食对早期肥胖大鼠模型中不同肥胖参数的影响，并确定这些参数是否与全身IR的标志物相关。此外，我们试图探讨空腹血液中IR指标（甘油三酯/高密度脂蛋白胆固醇[TAG/HDL-c]和甘油三酯-葡萄糖指数[TyG指数]）与脂肪细胞衍生的细胞外囊泡（adEV）大小之间的关系。
我们对暴露于高脂饮食的Wistar大鼠使用饮食诱导肥胖模型十周。通过双能X线吸收法分析最终体重增加情况。以附睾AT重量衡量内脏肥胖。通过空腹TyG指数和TAG/HDL-c评估IR，并在顶空培养中从成熟脂肪细胞中分离adEV。
与对照组相比，高脂饮食组的血糖和甘油三酯血液浓度更高（Log2FC分别高0.5倍和1.5倍）。对照组动物和高脂饮食组之间TyG指数值和adEV大小不同。多元线性回归分析表明，在控制附睾AT重量时，adEV大小可与TyG指数值显著相关。
我们的结果表明，在早期肥胖中，脂质和葡萄糖代谢以及adEV的大小和zeta电位已经改变，并且adEV大小可与通过TyG指数估计的肝脏和全身IR显著相关。
