Physiological role of CD206 macrophages and NAD+ metabolism in obesity and insulin resistance.

CD206 巨噬细胞和 NAD 代谢在肥胖和胰岛素抵抗中的生理作用。

• 批准号: 22K20737
• 负责人: Bilal Muhammad
• 金额: $ 1.83万
• 依托单位: University of Toyama
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Research Activity Start-up
• 财政年份: 2022
• 资助国家: 日本
• 起止时间: 2022-08-31 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-22K20737/
• 关键词: CD206; Nampt; Diabetes; CD206 Macrophages

First, I have successfully create of genetically engineered CD206+ M2like-macrophage-specific Nampt knock-out (KO) transgenic mice. I found that tamoxifen (TAM) administration did not affect the body weight of the chow-fed mice. After the administration of TAM I have performed ipGTT (intraperitoneal glucose tolerance test) and ITT (insulin tolerance test). My data showed that there is no significant difference between CD206 specific Nampt-KO mice and control mice normal chow-fed conditions. Then these mice were put on high fat diet (HFD). In consistent with my hypothesis, Nampt-KO mice gaining more body weight compared to the control mice. This data strongly suggested that CD206+ macrophages regulated diet-induced obesity or weight gain via Nampt-derived NAD+, with worsen glucose metabolism. My data suggest that CD206 gene have worsen effect on adipose tissue metabolism in obese states, which further worsen by Nampt KO. However, underlying molecular mechanism is unknown. My data also showed that CD206-positive macrophages shows inflammatory gene markers (Il1b, Tnfa, CD11c) after 12 weeks of HFD-feeding. Next, I am going to work on CD206-/-(CD206 gene knock-out) mice to evaluate how CD206 M2 macrophages is involved in regulation adipose tissue metabolism in obese conditions. I will perform GTT and ITT of these obese mice, and will harvest the tissue after sacrifice the mice. I will perform immunohistochemistry, RNA extraction, western blotting, flow cytometry, the qPCR of FACS sorted CD206+ macrophages to elucidate the underlying mechanism.

首先，我成功地创造了CD206+M2样巨噬细胞特异性NAMPT基因敲除(KO)转基因小鼠。我发现他莫昔芬()给药对喂食小鼠的体重没有影响。给药后，我进行了腹膜糖耐量试验和胰岛素耐量试验。我的数据显示，CD206特异性NAMPT-KO小鼠与正常饮食条件下的对照组小鼠之间没有显著差异。然后给这些小鼠喂高脂饮食(HFD)。与我的假设一致，与对照组相比，NAMPT-KO小鼠的体重增加了更多。这一数据强烈表明，CD206+巨噬细胞通过NAMPT衍生的NAD+调节饮食诱导的肥胖或体重增加，并导致糖代谢恶化。我的数据表明，CD206基因对肥胖状态下脂肪组织代谢的影响更差，而NAMPT KO进一步恶化了这一影响。然而，潜在的分子机制尚不清楚。我的数据还显示，在饲喂HFD 12周后，CD206阳性的巨噬细胞显示出炎症基因标志(IL1b、TNFa、CD11c)。接下来，我将对CD206-/-(CD206基因敲除)小鼠进行研究，以评估CD206 M2巨噬细胞如何参与肥胖条件下脂肪组织代谢的调节。我将对这些肥胖小鼠进行GTT和ITT，并在处死小鼠后采集组织。我将通过免疫组织化学、RNA提取、免疫印迹、流式细胞仪、定量聚合酶链式反应等方法对CD206+巨噬细胞进行分选，以阐明其可能的作用机制。