Department of Human Science, Georgetown University Medical Center, Washington, DC 20057, USA.
Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80012, USA.
Int J Mol Sci. 2022 May 18;23(10):5675. doi: 10.3390/ijms23105675.
Sodium-glucose co-transporters (SGLTs) serve to reabsorb glucose in the kidney. Recently, these transporters, mainly SGLT2, have emerged as new therapeutic targets for patients with diabetes and kidney disease; by inhibiting glucose reabsorption, they promote glycosuria, weight loss, and improve glucose tolerance. They have also been linked to cardiac protection and mitigation of liver injury. However, to date, the mechanism(s) by which SGLT2 inhibition promotes systemic improvements is not fully appreciated. Using an obese TallyHo mouse model which recapitulates the human condition of diabetes and nonalcoholic fatty liver disease (NAFLD), we sought to determine how modulation of renal glucose handling impacts liver structure and function. Apart from an attenuation of hyperglycemia, Empagliflozin was found to decrease circulating triglycerides and lipid accumulation in the liver in male TallyHo mice. This correlated with lowered hepatic cholesterol esters. Using in vivo MRI analysis, we further determined that the reduction in hepatic steatosis in male TallyHo mice was associated with an increase in nuchal white fat indicative of "healthy adipose expansion". Notably, this whitening of the adipose came at the expense of brown adipose tissue. Collectively, these data indicate that the modulation of renal glucose handling has systemic effects and may be useful as a treatment option for NAFLD and steatohepatitis.
钠-葡萄糖协同转运蛋白(SGLTs)在肾脏中起重吸收葡萄糖的作用。最近,这些转运蛋白,主要是 SGLT2,已成为糖尿病和肾病患者的新治疗靶点;通过抑制葡萄糖重吸收,它们促进糖尿、体重减轻和改善葡萄糖耐量。它们还与心脏保护和减轻肝损伤有关。然而,迄今为止,SGLT2 抑制促进全身改善的机制尚不完全清楚。使用肥胖 TallyHo 小鼠模型,该模型模拟了人类糖尿病和非酒精性脂肪性肝病(NAFLD)的状况,我们试图确定肾脏葡萄糖处理的调节如何影响肝脏结构和功能。除了降低高血糖外,恩格列净还被发现降低了雄性 TallyHo 小鼠循环中的甘油三酯和肝脏中的脂质积累。这与肝脏胆固醇酯降低有关。通过体内 MRI 分析,我们进一步确定,雄性 TallyHo 小鼠肝脏脂肪变性的减少与颈背部白色脂肪增加有关,表明“健康脂肪扩张”。值得注意的是,这种脂肪的变白是以棕色脂肪组织为代价的。总的来说,这些数据表明,肾脏葡萄糖处理的调节具有全身效应,可能是治疗非酒精性脂肪性肝病和脂肪性肝炎的一种有用方法。