High sodium intake enhances insulin-stimulated glucose uptake in rat epididymal adipose tissue
High sodium intake enhances insulin-stimulated glucose uptake in rat epididymal adipose tissue
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DOI：
10.1038/oby.2008.69
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发表时间：
2008-06-01
期刊：
影响因子：
6.9
通讯作者：
Lima, Fabio B.
中科院分区：
文献类型：
--
作者：
Fonseca-Alaniz, Miriam H.;Takada, Julie;Lima, Fabio B.
目的：本研究探讨了不同钠含量的饮食对大鼠脂肪组织碳水化合物代谢和胰岛素sensitivity.Methods和程序的影响：雄性Wistar大鼠喂养正常（0.5%Na +; NS），高（3.12%Na +; HS），或低钠（0.06%Na +; LS）的饮食3，6，和9周后断奶。血压（BP）测量使用计算机尾袖系统。在禁食动物中进行静脉内胰岛素耐量试验（ivITT）。在每个阶段结束时，处死大鼠并采集血样用于葡萄糖和胰岛素测定。取腹部和腹股沟皮下（SC）和附睾周围（PE）贮库的白色脂肪组织（WAT），称重并处理用于脂肪细胞分离和测量胰岛素刺激的2-脱氧-d-[H-3]-葡萄糖摄取（2DGU）和[U-C-14]-葡萄糖转化为（CO2）-C-14的体外速率。6周后，HS饮食显著增加BP、SC和PE WAT质量、PE脂肪细胞大小和血浆胰岛素浓度。钠饮食含量不影响全身胰岛素敏感性。在来自HS大鼠的分离的PE脂肪细胞中观察到来自2DGU的剂量-反应曲线的较高的半数最大有效胰岛素浓度（EC 50）和胰岛素刺激的葡萄糖氧化速率的增加。慢性盐超负荷增强了脂肪细胞对葡萄糖摄取的胰岛素敏感性和胰岛素诱导的葡萄糖代谢，有助于促进脂肪细胞肥大并增加几个脂肪库的质量，特别是PE脂肪垫。
Objective: This study investigated the effect of different sodium content diets on rat adipose tissue carbohydrate metabolism and insulin sensitivity.Methods and Procedures: Male Wistar rats were fed on normal- (0.5% Na+; NS), high- (3.12% Na+; HS), or low-sodium (0.06% Na+; LS) diets for 3, 6, and 9 weeks after weaning. Blood pressure (BP) was measured using a computerized tail-cuff system. An intravenous insulin tolerance test (ivITT) was performed in fasted animals. At the end of each period, rats were killed and blood samples were collected for glucose and insulin determinations. The white adipose tissue (WAT) from abdominal and inguinal subcutaneous (SC) and periepididymal (PE) depots were weighed and processed for adipocyte isolation and measurement of in vitro rates of insulin-stimulated 2-deoxy-d-[H-3]-glucose uptake (2DGU) and conversion of -[U-C-14]-glucose into (CO2)-C-14.Results: After 6 weeks, HS diet significantly increased the BP, SC and PE WAT masses, PE adipocyte size, and plasma insulin concentration. The sodium dietary content did not influence the whole-body insulin sensitivity. A higher half-maximal effective insulin concentration (EC50) from the dose - response curve of 2DGU and an increase in the insulin-stimulated glucose oxidation rate were observed in the isolated PE adipocytes from HS rats.Discussion: The chronic salt overload enhanced the adipocyte insulin sensitivity for glucose uptake and the insulin-induced glucose metabolization, contributing to promote adipocyte hypertrophy and increase the mass of several adipose depots, particularly the PE fat pad.