Laboratory of Experimental Hepatology, Department of Pharmacology, Cinvestav-IPN, Mexico City, Mexico.
Department of Infectomics and Molecular Pathogenesis, Cinvestav-IPN, Mexico City, Mexico.
Ann Hepatol. 2019 May-Jun;18(3):472-479. doi: 10.1016/j.aohep.2018.10.002. Epub 2019 Apr 15.
Stevia has exhibited antioxidant, antihyperglycemic, antihypertensive and anti-inflammatory properties in several in vivo and in vitro models. The objective of this study was to investigate the ability of an aqueous extract of stevia (AES) to prevent experimental cirrhosis in rats and to explore its mechanism of action.
Liver cirrhosis was induced by administering carbon tetrachloride (CCl) (400mg/kg by i.p. injection 3 times a week for 12 weeks); AES was administered (100mg/kg by gavage daily) during the CCl treatment. Fibrosis was evaluated with histological, biochemical and molecular approaches, and liver damage was assessed with standardized procedures. The profibrotic pathways were analyzed by western blotting, qRT-PCR and immunohistochemistry.
Chronic CCl administration increased nuclear factor kappa B (NF-κB) and proinflammatory cytokine production as well as oxidative parameters such as lipid peroxidation and 4-hydroxynonenal levels, whereas GSH and nuclear factor-E2-related factor 2 (Nrf2) levels were decreased. CCl induced profibrogenic mediator expression, hepatic stellate cell (HSC) activation and, consequently, extracellular matrix production. AES exhibited antioxidant, anti-inflammatory and antifibrotic properties, probably because of its capacity to induce Nrf2 expression, reduce NF-κB expression and block several profibrogenic signaling pathways, subsequently inhibiting HSC activation and preventing fibrosis induced by chronic CCl administration.
甜菊已在多种体内和体外模型中表现出抗氧化、降血糖、降血压和抗炎特性。本研究的目的是研究甜菊的水提取物(AES)预防大鼠实验性肝纤维化的能力,并探讨其作用机制。
通过腹腔注射(每周 3 次,每次 400mg/kg)四氯化碳(CCl)诱导肝纤维化(共 12 周);在 CCl 治疗期间,AES 通过灌胃(每天 100mg/kg)给药。采用组织学、生化和分子方法评估纤维化,采用标准化程序评估肝损伤。通过 Western blot、qRT-PCR 和免疫组织化学分析促纤维化途径。
慢性 CCl 给药增加了核因子 kappa B(NF-κB)和促炎细胞因子的产生,以及氧化参数,如脂质过氧化和 4-羟基壬烯醛水平,而 GSH 和核因子-E2 相关因子 2(Nrf2)水平降低。CCl 诱导了促纤维化介质的表达、肝星状细胞(HSC)的激活,以及细胞外基质的产生。AES 表现出抗氧化、抗炎和抗纤维化特性,可能是因为它能够诱导 Nrf2 表达,降低 NF-κB 表达并阻断几种促纤维化信号通路,从而抑制 HSC 激活并预防慢性 CCl 给药引起的纤维化。