Touchstone Diabetes Center, The University of Texas Southwestern Medical Center, Dallas, US.
Division of Lymphatic Biology, Department of Medical Physiology, Texas A&M University College of Medicine, Bryan, TX, USA.
Nat Commun. 2023 Oct 17;14(1):6531. doi: 10.1038/s41467-023-42188-4.
Adiponectin is a secretory protein, primarily produced in adipocytes. However, low but detectable expression of adiponectin can be observed in cell types beyond adipocytes, particularly in kidney tubular cells, but its local renal role is unknown. We assessed the impact of renal adiponectin by utilizing male inducible kidney tubular cell-specific adiponectin overexpression or knockout mice. Kidney-specific adiponectin overexpression induces a doubling of phosphoenolpyruvate carboxylase expression and enhanced pyruvate-mediated glucose production, tricarboxylic acid cycle intermediates and an upregulation of fatty acid oxidation (FAO). Inhibition of FAO reduces the adiponectin-induced enhancement of glucose production, highlighting the role of FAO in the induction of renal gluconeogenesis. In contrast, mice lacking adiponectin in the kidney exhibit enhanced glucose tolerance, lower utilization and greater accumulation of lipid species. Hence, renal adiponectin is an inducer of gluconeogenesis by driving enhanced local FAO and further underlines the important systemic contribution of renal gluconeogenesis.
脂联素是一种分泌蛋白,主要在脂肪细胞中产生。然而,在脂肪细胞以外的细胞类型中也可以观察到低但可检测到的脂联素表达,特别是在肾小管细胞中,但它在局部肾脏中的作用尚不清楚。我们利用雄性可诱导肾小管细胞特异性脂联素过表达或敲除小鼠来评估肾脏脂联素的影响。肾脏特异性脂联素过表达导致磷酸烯醇丙酮酸羧激酶表达增加一倍,并增强了丙酮酸介导的葡萄糖生成、三羧酸循环中间产物和脂肪酸氧化 (FAO)。FAO 的抑制减少了脂联素诱导的葡萄糖生成增强,突出了 FAO 在诱导肾脏糖异生中的作用。相比之下,肾脏中缺乏脂联素的小鼠表现出增强的葡萄糖耐量、更低的利用和更大的脂质种类积累。因此,肾脏脂联素通过驱动增强的局部 FAO 诱导糖异生,并进一步强调了肾脏糖异生对全身的重要贡献。