Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02215, USA.
Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02215, USA; Institute of Biochemistry, Food Science and Nutrition, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Jerusalem, Israel.
Cell Chem Biol. 2024 Oct 17;31(10):1772-1786.e5. doi: 10.1016/j.chembiol.2024.09.001. Epub 2024 Sep 27.
Small molecules selectively inducing peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1α acetylation and inhibiting glucagon-dependent gluconeogenesis causing anti-diabetic effects have been identified. However, how these small molecules selectively suppress the conversion of gluconeogenic metabolites into glucose without interfering with lipogenesis is unknown. Here, we show that a small molecule SR18292 inhibits hepatic glucose production by increasing lactate and glucose oxidation. SR18292 increases phosphoenolpyruvate carboxykinase 1 (PCK1) acetylation, which reverses its gluconeogenic reaction and favors oxaloacetate (OAA) synthesis from phosphoenolpyruvate. PCK1 reverse catalytic reaction induced by SR18292 supplies OAA to tricarboxylic acid (TCA) cycle and is required for increasing glucose and lactate oxidation and suppressing gluconeogenesis. Acetylation mimetic mutant PCK1 K91Q favors anaplerotic reaction and mimics the metabolic effects of SR18292 in hepatocytes. Liver-specific expression of PCK1 K91Q mutant ameliorates hyperglycemia in obese mice. Thus, SR18292 blocks gluconeogenesis by enhancing gluconeogenic substrate oxidation through PCK1 lysine acetylation, supporting the anti-diabetic effects of these small molecules.
已鉴定出可选择性诱导过氧化物酶体增殖物激活受体γ共激活因子(PGC)-1α乙酰化并抑制胰高血糖素依赖性糖异生从而产生抗糖尿病作用的小分子。然而,这些小分子如何在不干扰脂肪生成的情况下选择性地抑制糖异生代谢物转化为葡萄糖尚不清楚。在这里,我们发现小分子 SR18292 通过增加乳酸和葡萄糖氧化来抑制肝葡萄糖生成。SR18292 增加磷酸烯醇丙酮酸羧激酶 1(PCK1)乙酰化,这可逆转其糖异生反应,并有利于从磷酸烯醇丙酮酸合成草酰乙酸(OAA)。由 SR18292 诱导的 PCK1 反向催化反应为三羧酸(TCA)循环提供 OAA,并且对于增加葡萄糖和乳酸氧化以及抑制糖异生是必需的。乙酰化模拟突变体 PCK1 K91Q 有利于补料反应,并模拟了 SR18292 在肝细胞中的代谢作用。PCK1 K91Q 突变体在肝脏中的特异性表达可改善肥胖小鼠的高血糖症。因此,SR18292 通过增强 PCK1 赖氨酸乙酰化的糖异生底物氧化来阻断糖异生,从而支持这些小分子的抗糖尿病作用。