珠子参叶皂苷对脂肪酶抑制机制及降血脂研究

Inhibition mechanisms and hypolipidemic effects on lipase of saponins from Panax japonicas var. major leaves

关键词:  珠子参叶, 皂苷, 脂肪酶, 酶动力学, 分子对接, 体内验证

Key words:  Panax japonicas var. major leaves, saponin, lipase, enzyme kinetics, molecular docking, verification in vivo

摘要:

珠子参叶是五加科(Araliaca)植物珠子参(Panax japonicas var. major)的干燥带梗叶,为秦巴地区特色中药材。为合理开发利用珠子参叶并阐明其化学成分,该研究利用HPLC方法分析珠子参叶皂苷部位的主要化学成分,测定珠子参叶皂苷部位的脂肪酶抑制活性及抑制类型,通过分子对接及动物实验验证脂肪酶抑制机制及降血脂作用。结果表明:(1)珠子参叶皂苷部位主要成分为20(S)-人参皂苷Rg₂、20(R)-人参皂苷Rg₂、人参皂苷Rb₂、人参皂苷Rb₃、人参皂苷Rd、人参皂苷Rh₂。(2)珠子参叶皂苷部位、20(R)-人参皂苷 Rg₂对脂肪酶具有较强的抑制作用,其IC₅₀分别为0.14、2.30 μmol·L^-1。(3)珠子参叶皂苷部位、20(R)-人参皂苷Rg₂、人参皂苷Rb₃对脂肪酶的抑制为可逆性抑制,抑制类型为非竞争型抑制。(4)配体与ARG337B、ASP331B、ILE248B残基结合可能有助于提高配体的脂肪酶抑制活性。(5)珠子参叶总皂苷可以显著降低高脂血症小鼠血清中胆固醇和甘油三酯的含量。该研究为珠子参叶在降血脂方面的深入开发和利用提供了理论参考。

Abstract:

The dry aerial part of Panax japonicus var. major is called “Zhuzishen Ye”, it is a characteristic Chinese herbal medicine in Qinba area. In order to rationally develop and utilize “Zhuzishen Ye” and clarify its chemical constituents, the main chemical constituents of the saponin fractions from “Zhuzishen Ye” were analyzed with HPLC, the inhibitory activities and inhibition types of the saponin fractions of “Zhuzishen Ye” on lipase were determined, and the lipase inhibition mechanisms and hypolipidemic effects were verified with molecular docking and animal experiments. The results were as follows:(1)The chemical constituents of saponin fractions from “Zhuzishen Ye” were 20(S)-ginsenoside Rg₂, 20(R)-ginsenoside Rg₂, ginsenoside Rb₂, ginsenoside Rb₃, ginsenoside Rd and ginsenoside Rh₂.(2)The saponin fractions of “Zhuzishen Ye” and 20(R)-ginsenoside Rg₂ had strong inhibitory effects on lipase with IC₅₀ values of 0.14 and 2.30 μmol·L^-1, respectively.(3)The saponin fractions of “Zhuzishen Ye”, 20(R)-ginsenoside Rg₂ and ginsenoside Rb₃ were all reversible inhibition, and the inhibition type was non-competitive inhibition.(4)The binding of ligands to ARG337B, ASP331B and ILE248B residues might help to improve the lipase inhibitory activity of ligands.(5)Saponins of “Zhuzishen Ye” could significantly reduce the content of cholesterol and triglyceride in serum of hyperlipidemia mice. This study provides the theoretical references for the further development and utilization of “Zhuzishen Ye”.