胰岛素失调的冰岛马中的胰岛素信号
F Frers1, J Delarocque1, K Feige1
1Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Bünteweg 9, Hannover 30559, Germany.
Domestic animal endocrinology
|November 4, 2024
概括
马的胰岛素失调涉及肝脏,肌肉和脂肪组织中蛋白质信号的改变. 拉帕素 (mTOR) 途径的机械性标在马类代谢条件中显得至关重要.
科学领域:
- 马类生理学 马类生理学
- 代谢研究的研究.
- 分子生物学分子生物学
背景情况:
- 马中的胰岛素失调 (ID) 机制尚不清楚.
- 研究肝脏,肌肉和脂肪组织中关键蛋白质信号传递对于理解ID至关重要.
- 马类代谢综合征和 pituitary pars 中介功能障碍是导致 ID 的潜在因素.
研究的目的:
- 为了确定马匹的胰岛素失调是否与胰岛素信号蛋白的基底表达和酸化变化有关.
- 为了在基底和刺激条件下比较胰岛素失调 (HI) 和胰岛素正常 (NI) 马的胰岛素信号通路.
- 探索拉巴胺素 (mTOR) 途径机械性标在马类胰岛素失调中的作用.
主要方法:
- 一项涉及口服葡萄糖 (Gluc PO) 和静脉注射胰岛素 (Ins IV) 的交叉研究,对12匹冰岛马进行了挑战.
- 肝脏 (LT),肌肉 (MT) 和皮下脂肪组织 (AT) 的活检是在基底和刺激条件下收集的.
- 西部斑点分析被用来评估蛋白质酸化,用ELISA测量胰岛素水平.
主要成果:
- 在12匹马中,有6匹马 (HI) 根据挑战后胰岛素水平升高而发现胰岛素失调.
- 在葡萄糖和胰岛素刺激下,在肝脏组织中观察到增强的胰岛素受体 (InsR) 酸化.
- 葡萄糖后,蛋白质激酶B的酸化在所有组织中增加,在胰岛素后在肌肉/脂肪中增加;腺单酸蛋白质激酶α酸化在葡萄糖后减少.
- HI马在肌肉组织中显示了显著更高的酸化机械标拉巴胺素 (mTOR).
- 在葡萄糖刺激后,HI和NI马的肝脏mTOR酸化模式不同.
结论:
- 冰岛马的胰岛素信号似乎总体保持不变,但在胰岛素失调时,后受体变化是显而易见的.
- 拉巴胺素 (mTOR) 信号通路的机械性标可能在马类胰岛素失调中发挥重要作用.
- 在HI马的肌肉组织中较高的mTOR酸化表明它参与了马类特定的代谢条件.
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