Laboratório de Experimentação Animal e Laboratório de Cardiologia Molecular e Celular, Instituto de Cardiologia/Fundação, Universitária de Cardiologia, Bairro Santana, Porto Alegre, RS, Brazil.
Cardiovasc Diabetol. 2012 Aug 16;11:100. doi: 10.1186/1475-2840-11-100.
Metabolic syndrome is characterized by insulin resistance, which is closely related to GLUT4 content in insulin-sensitive tissues. Thus, we evaluated the GLUT4 expression, insulin resistance and inflammation, characteristics of the metabolic syndrome, in an experimental model.
Spontaneously hypertensive neonate rats (18/group) were treated with monosodium glutamate (MetS) during 9 days, and compared with Wistar-Kyoto (C) and saline-treated SHR (H). Blood pressure (BP) and lipid levels, C-reactive protein (CRP), interleukin 6 (IL-6), TNF-α and adiponectin were evaluated. GLUT4 protein was analysed in the heart, white adipose tissue and gastrocnemius. Studies were performed at 3 (3-mo), 6 (6-mo) and 9 (9-mo) months of age.
MetS rats were more insulin resistant (p<0.001, all ages) and had higher BP (3-mo: p<0.001, 6-mo: p = 0.001, 9-mo: p = 0.015) as compared to C. At 6 months, CRP, IL-6 and TNF-α were higher (p<0.001, all comparisons) in MetS rats vs H, but adiponectin was lower in MetS at 9 months (MetS: 32 ± 2, H: 42 ± 2, C: 45 ± 2 pg/mL; p<0.001). GLUT4 protein was reduced in MetS as compared to C rats at 3, 6 and 9-mo, respectively (Heart: 54%, 50% and 57%; Gastrocnemius: 37%, 56% and 50%; Adipose tissue: 69%, 61% and 69%).
MSG-treated SHR presented all metabolic syndrome characteristics, as well as reduced GLUT4 content, which must play a key role in the impaired glycemic homeostasis of the metabolic syndrome.
代谢综合征的特征是胰岛素抵抗,这与胰岛素敏感组织中的 GLUT4 含量密切相关。因此,我们在实验模型中评估了 GLUT4 表达、胰岛素抵抗和炎症,这些都是代谢综合征的特征。
18 只自发性高血压新生儿大鼠(每组)接受 9 天的谷氨酸单钠(MetS)治疗,并与 Wistar-Kyoto(C)和盐水处理的 SHR(H)进行比较。评估血压(BP)和血脂水平、C 反应蛋白(CRP)、白细胞介素 6(IL-6)、肿瘤坏死因子-α(TNF-α)和脂联素。分析心脏、白色脂肪组织和比目鱼肌中的 GLUT4 蛋白。研究在 3(3 个月)、6(6 个月)和 9(9 个月)个月时进行。
MetS 大鼠的胰岛素抵抗更严重(p<0.001,所有年龄),且血压更高(3 个月:p<0.001,6 个月:p = 0.001,9 个月:p = 0.015)与 C 相比。6 个月时,MetS 大鼠的 CRP、IL-6 和 TNF-α 更高(所有比较 p<0.001),但 MetS 大鼠的脂联素在 9 个月时较低(MetS:32±2,H:42±2,C:45±2pg/mL;p<0.001)。与 C 大鼠相比,MetS 大鼠在 3、6 和 9 个月时的 GLUT4 蛋白分别降低(心脏:54%、50%和 57%;比目鱼肌:37%、56%和 50%;脂肪组织:69%、61%和 69%)。
接受谷氨酸单钠治疗的 SHR 表现出所有代谢综合征特征,以及 GLUT4 含量降低,这在代谢综合征的血糖稳态受损中起着关键作用。