Department of Medical Sciences, Clinical Diabetology and Metabolism, Uppsala University, Uppsala, Sweden.
Department of Surgical Sciences, Transplantation Surgery, Uppsala University, Uppsala, Sweden.
Obesity (Silver Spring). 2024 Oct;32(10):1870-1884. doi: 10.1002/oby.24114. Epub 2024 Aug 29.
The objective was to study metabolic characteristics and transcriptome of renal sinus adipose tissue (RSAT) located around renal arteries and veins.
Adipose tissue biopsies from RSAT, omental (OAT), and subcutaneous (SAT) depots were obtained from healthy kidney donors (20 female, 20 male). Adipocyte glucose uptake rate and cell size were measured, and gene expression analyses using transcriptomics were performed.
RSAT adipocytes were significantly smaller, with a higher basal glucose uptake rate, than adipocytes from SAT and OAT. Transcriptomic analyses revealed 29 differentially expressed genes between RSAT and OAT (RSAT: 23 lower, 6 higher) and 1214 differentially expressed genes between RSAT and SAT (RSAT: 859 lower, 355 higher). RSAT demonstrated molecular resemblance to OAT, both exhibiting lower metabolic gene expression and higher expression of immune-related pathways, including IL-17, TNFα, and NF-κB signaling than SAT. Weighted gene coexpression network analysis associated RSAT with immune response and nucleic acid transport processes. Despite its location near the renal hilum, RSAT closely resembled OAT and there was a lack of expression in the classical brown adipose tissue genes. Gene enrichment analyses suggest an inflammatory environment in RSAT compared with SAT and, to some extent, OAT.
The findings suggest specific RSAT functions that could impact renal function and, possibly, the development of renal and cardiometabolic disorders.
研究位于肾动静脉周围的肾窦脂肪组织（RSAT）的代谢特征和转录组。
从健康肾脏供体（女性 20 名，男性 20 名）获取 RSAT、网膜（OAT）和皮下（SAT）脂肪组织的脂肪组织活检。测量脂肪细胞的葡萄糖摄取率和细胞大小，并进行转录组学分析。
RSAT 脂肪细胞明显小于 SAT 和 OAT 脂肪细胞，基础葡萄糖摄取率更高。转录组分析显示 RSAT 和 OAT 之间有 29 个差异表达基因（RSAT：23 个下调，6 个上调），RSAT 和 SAT 之间有 1214 个差异表达基因（RSAT：859 个下调，355 个上调）。RSAT 与 OAT 具有分子相似性，两者的代谢基因表达均较低，免疫相关途径（包括 IL-17、TNFα 和 NF-κB 信号通路）的表达较高，而 SAT 则较低。加权基因共表达网络分析将 RSAT 与免疫反应和核酸转运过程相关联。尽管位于肾门附近，但 RSAT 与 OAT 非常相似，缺乏经典棕色脂肪组织基因的表达。基因富集分析表明，与 SAT 相比，RSAT 存在炎症环境，在某种程度上与 OAT 也存在炎症环境。
这些发现表明 RSAT 具有特定的功能，可能影响肾功能，并可能影响肾脏和心脏代谢疾病的发展。
