Li Chunpu, Hu Sha-Sha, Yang Lisheng, Wang Min, Long Jian-Dong, Wang Bing, Han Haozhen, Zhu Haoran, Zhao Sen, Liu Jing-Gen, Liu Dongxiang, Liu Hong
State Key Laboratory of Drug Research, Department of Pharmacology III, and Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 555 Zu-Chong-Zhi Road, Shanghai 201203, China.
School of Pharmaceutical Science and Technology, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China.
ACS Med Chem Lett. 2021 Mar 1;12(3):397-403. doi: 10.1021/acsmedchemlett.0c00559. eCollection 2021 Mar 11.
SIRT1, a member of the sirtuin family, catalyzes the deacetylation of proteins with the transformation of NAD into nicotinamide and 2'--acetyl-ADP-ribose. Selective SIRT1/2 inhibitors have potential application in the chemotherapy of colorectal carcinoma, prostate cancer, and myelogenous leukemia. Here we identified novel SIRT1 inhibitors with the scaffold of 5-benzylidene-2-phenyl-1,3-dioxane-4,6-dione. The most potent inhibitor displayed an IC of 460 nM and a selectivity for SIRT1 over SIRT2, SIRT3, and SIRT5 of 113.5-, 254.3-, and 10.83-fold, respectively. It did not affect the activity of SIRT6. To elucidate the inhibitory mechanism, we determined the inhibition type of the inhibitor by enzyme kinetic analysis, showing that the inhibitor was competitive to the acetyl peptide and noncompetitive to NAD. Further, the interaction of the inhibitor in SIRT1 was studied by using molecular docking, which was validated by the structure-activity relationship analysis of the inhibitors and the site-directed mutagenesis of SIRT1. Consistent with the assays, the inhibitors increased the acetylation level of p53 in a concentration-dependent manner in cells.
SIRT1是沉默调节蛋白家族的一员，它通过将NAD转化为烟酰胺和2'-O-乙酰-ADP-核糖来催化蛋白质的去乙酰化反应。选择性SIRT1/2抑制剂在结直肠癌、前列腺癌和骨髓性白血病的化疗中具有潜在应用价值。在此，我们鉴定出了具有5-亚苄基-2-苯基-1,3-二氧六环-4,6-二酮骨架的新型SIRT1抑制剂。最有效的抑制剂的IC50为460 nM，对SIRT1相对于SIRT2、SIRT3和SIRT5的选择性分别为113.5倍、254.3倍和10.83倍。它不影响SIRT6的活性。为了阐明抑制机制，我们通过酶动力学分析确定了抑制剂的抑制类型，结果表明该抑制剂对乙酰化肽具有竞争性，对NAD具有非竞争性。此外，通过分子对接研究了抑制剂与SIRT1的相互作用，并通过抑制剂的构效关系分析和SIRT1的定点诱变进行了验证。与实验结果一致，这些抑制剂在细胞中以浓度依赖性方式增加了p53的乙酰化水平。
