Fudan University School of Pharmacy, Shanghai 201203, China.
Fudan University School of Pharmacy, Shanghai 201203, China.
Biochem Pharmacol. 2024 May;223:116167. doi: 10.1016/j.bcp.2024.116167. Epub 2024 Mar 26.
Nonalcoholic fatty liver disease (NAFLD) prevalence is rising globally with no pharmacotherapies approved. Hepatic steatosis is closely associated with progression and prognosis of NAFLD. Dapagliflozin, kind of sodium-glucose cotransporter 2 (SGLT2) inhibitor, was found to improve NAFLD in clinical trials, while the underlying mechanism remains poorly elucidated. Here, we reported that dapagliflozin effectively mitigated liver injury and relieved lipid metabolism disorders in vivo. Further investigation showed that dapagliflozin markedly suppressed Liver X Receptor α (LXRα)-mediated synthesis of de novo lipids and bile acids (BAs). In AML12 cells, our results proved dapagliflozin decreased lipid contents via inhibiting the expression of LXRα and downstream liposynthesis genes. Proteosome inhibitor MG132 eliminated the effect of dapagliflozin on LXRα-mediated signaling pathway, which suggested that dapagliflozin downregulated LXRα expression through increasing LXRα degradation. Knockdown of LXRα with siRNA abolished the reduction of lipogenesis from dapagliflozin treatment, indicating that LXRα might be the pivotal target for dapagliflozin to exhibit the aforementioned benefits. Furthermore, the data showed that dapagliflozin reversed gut dysbiosis induced by BAs disruption and altered gut microbiota profile to reduce intestinal lipids absorption. Together, our study deciphered a novel mechanism by which dapagliflozin relieved hepatic steatosis and highlighted the potential benefit of dapagliflozin in treating NAFLD.
非酒精性脂肪性肝病 (NAFLD) 的全球患病率正在上升,但尚无批准的药物治疗方法。肝脂肪变性与 NAFLD 的进展和预后密切相关。达格列净是一种钠-葡萄糖共转运蛋白 2 (SGLT2) 抑制剂,已在临床试验中被发现可改善 NAFLD,但潜在机制仍未得到充分阐明。在这里,我们报告达格列净可有效减轻体内肝损伤并缓解脂质代谢紊乱。进一步的研究表明,达格列净显著抑制了肝 X 受体α (LXRα) 介导的新脂质和胆汁酸 (BAs) 的合成。在 AML12 细胞中,我们的结果证明达格列净通过抑制 LXRα 和下游脂肪合成基因的表达来减少脂质含量。蛋白酶体抑制剂 MG132 消除了达格列净对 LXRα 介导的信号通路的影响,这表明达格列净通过增加 LXRα 的降解来下调 LXRα 的表达。用 siRNA 敲低 LXRα 可消除达格列净治疗引起的脂肪生成减少,表明 LXRα 可能是达格列净发挥上述益处的关键靶标。此外,数据表明达格列净可逆转 BAs 破坏引起的肠道菌群失调,并改变肠道微生物群谱以减少肠道脂质吸收。总之,我们的研究揭示了达格列净缓解肝脂肪变性的新机制,并强调了达格列净在治疗 NAFLD 方面的潜在益处。