title: Protostane Triterpenoids from the Rhizome of Alisma orientale Exhibit Inhibitory Effects on Human Carboxylesterase 2.
abstract: Twelve new and 10 known protostane triterpenoids were isolated from the rhizome of Alisma orientale. Their structures were elucidated based on physical data analyses, including UV, HRESIMS, NMR experiments ((1)H, (13)C NMR, (1)H-(1)H COSY, HSQC, HMBC, and NOESY), and induced electronic circular dichroism. New compounds 1-12 were classified as protostanes (1-10), 29-norprotostane (11), and 24-norprotostane (12) by structure analyses. Furthermore, the inhibitory effects on human carboxylesterases (hCE-1, hCE-2) of compounds 1-22 were evaluated. Compounds 2, 6, 9, and 11 showed moderate inhibitory activities and were selective toward hCE-2 enzymes, with IC50 values of 8.68, 4.72, 4.58, and 2.02 μM, respectively. The inhibition kinetics of compound 11 toward hCE-2 were established, and the Ki value was determined as 1.76 μM using a mixed inhibition model. The interaction of bioactive compound 11 with hCE-2 was shown using molecular docking.
authors.forename: Zhen-Peng
authors.initials: ZP
authors.lastname: Mai
authors.affiliation: College of Pharmacy, Liaoning University of Traditional Chinese Medicine , Dalian 110847, People's Republic of China.
authors.forename: Kun
authors.initials: K
authors.lastname: Zhou
authors.affiliation: Laboratory of Pharmaceutical Resource Discovery, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, People's Republic of China.
authors.forename: Guang-Bo
authors.initials: GB
authors.lastname: Ge
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Xiao-Kui
authors.initials: XK
authors.lastname: Huo
authors.forename: Pei-Pei
authors.initials: PP
authors.lastname: Dong
authors.forename: Sa
authors.initials: S
authors.lastname: Deng
authors.forename: Bao-Jing
authors.initials: BJ
authors.lastname: Zhang
authors.forename: Hou-Li
authors.initials: HL
authors.lastname: Zhang
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Huang
authors.forename: Xiao-Chi
authors.initials: XC
authors.lastname: Ma
mesh_terms: D034902:Alisma / Q000737:chemistry*; D043182:Carboxylesterase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000493:pharmacokinetics / Q000494:pharmacology*; D006801:Humans; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000737:chemistry; D027343:Rhizome / Q000737:chemistry; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000493:pharmacokinetics / Q000494:pharmacology*
chemical_list: C000604763:29-norprotostane; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; D014315:Triterpenes; C517204:CES2 protein, human; D043182:Carboxylesterase