College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea.
College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea.
Mol Metab. 2024 Dec;90:102039. doi: 10.1016/j.molmet.2024.102039. Epub 2024 Sep 27.
Adipose tissue remodeling plays a critical role in obesity-induced metabolic dysfunction, but the underlying molecular mechanisms remain incompletely understood. This study investigates the role of miR-10a-5p in adipose tissue inflammation and metabolic dysfunction induced by a high-fat diet (HFD).
Male miR-10a knockout (KO) mice were fed a HFD to induce obesity for up to 16 weeks. RNA sequencing (RNA-seq) analysis was performed to profile mRNA expression and assess the effects of miR-10a-5p KO in gonadal white adipose tissue (gWAT). Additional analyses included immunoblotting, qPCR, histological examination, and validation of the miR-10a-5p target sequence using a dual-luciferase reporter assay.
miR-10a-5p was highly expressed in gWAT but decreased after 8 weeks of HFD feeding. Over the 16-week HFD period, miR-10a KO mice exhibited greater weight gain and reduced energy expenditure compared to wild-type (WT) controls. gWAT of miR-10a KO mice on a HFD showed an increased population of proinflammatory macrophages, elevated inflammation, and increased cell death, characterized by upregulated apoptosis and necrosis markers. This was also associated with increased triglyceride accumulation in liver. Mechanistically, the proapoptotic gene Bcl2l11 was identified as a direct target of miR-10a-5p. Loss of miR-10a-5p led to BIM-mediated adipocyte death and inflammation, contributing to mitochondrial metabolic dysregulation, increased fibrosis marker expression, and the onset of inflammation in adipose tissue.
This study demonstrates the significant role of miR-10a-5p and its downstream target BIM in regulating adipocyte death during diet-induced obesity. This signaling pathway presents a potential therapeutic target for modulating obesity-induced inflammation and cell death in adipose tissue.
脂肪组织重塑在肥胖引起的代谢功能障碍中起着关键作用,但其中的分子机制尚不完全清楚。本研究探讨了 miR-10a-5p 在高脂肪饮食(HFD)诱导的脂肪组织炎症和代谢功能障碍中的作用。
雄性 miR-10a 敲除(KO)小鼠喂食 HFD 长达 16 周以诱导肥胖。进行 RNA 测序(RNA-seq)分析以描绘 mRNA 表达,并评估 miR-10a-5p KO 在性腺白色脂肪组织(gWAT)中的影响。其他分析包括免疫印迹、qPCR、组织学检查以及使用双荧光素酶报告基因检测来验证 miR-10a-5p 的靶序列。
miR-10a-5p 在 gWAT 中高度表达,但在 HFD 喂养 8 周后降低。在 16 周的 HFD 期间,与野生型(WT)对照相比,miR-10a KO 小鼠表现出更大的体重增加和能量消耗减少。HFD 喂养的 miR-10a KO 小鼠的 gWAT 中促炎巨噬细胞数量增加,炎症加剧,细胞死亡增加,特征为凋亡和坏死标志物上调。这也与肝脏中甘油三酯积累增加有关。在机制上,促凋亡基因 Bcl2l11 被鉴定为 miR-10a-5p 的直接靶标。miR-10a-5p 的缺失导致 BIM 介导的脂肪细胞死亡和炎症,导致线粒体代谢失调、纤维化标志物表达增加以及脂肪组织炎症的发生。
本研究表明 miR-10a-5p 及其下游靶标 BIM 在调节饮食诱导肥胖期间脂肪细胞死亡中起着重要作用。该信号通路为调节肥胖诱导的脂肪组织炎症和细胞死亡提供了一个潜在的治疗靶点。