The ingredient of red wine, resveratrol, aggravates the effects of free fatty acids (FFA) on the hepatic stellate cell line LX–2

• Published in: Zeitschrift für Gastroenterologie
• Main Authors: Zahn, D, Marquitan, G, Bechmann, L, Schlattjan, M, Gerken, G, Canbay, A
• Format: Conference Proceeding
• Language: English
• Published: 23.01.2008
• Subjects: Free Fatty Acids; Fibrosis; Resveratrol; Death-Receptors; Apoptosis
• ISSN: 0044-2771; 1439-7803
• DOI: 10.1055/s-2008-1037458

Aims: One of the candidates to exert the beneficial effects of moderate consumption of red wine is resveratrol (trans–3,5,4´-trihydroxystilbene), a nonflavonoid polyphenol with antioxidative, anticancer, and antiinflammatory properties. It has been shown to improve health and survival in obese mice. In contrast, FFAs play an important role in liver fibrogenesis and act as profibrotic factors. Among other effects, FFA induce apoptosis, a prominent feature of NAFLD. Our Aim was to ascertain whether resveratrol affects the expression of FFA-induced pro-fibrogenic genes and/or the expression of death receptors (DRs) and apoptosis-related molecules in LX–2 cells. Methods: LX–2 cells were cultured for 48h in the presence of 0.5 mM FFAs (2: 1 oleate: palmitate) and treated for an additional 24h with or without resveratrol at different concentrations (5, 10, or 15 μM). The expression of fibrosis-related genes as well as apoptosis related genes was quantified by real-time RT-PCR. Results were expressed as a ratio against the housekeeping gene SDHA and normalized to the values of the negative controls. Cytotoxicity assays (1-(4,5-Dimethylthiazol–2-yl)–3,5-diphenylformazan=MTT) and proliferation assays BrdU were used to quantify the 50% lethal and inhibitory doses LD50 and ID50 of resveratrol in the presence of 0.5 mM FFA. Results: Incubation of LX–2 cells with 0.5mM FFA resulted in a slight induction of activation- and fibrosis-related genes (α-SMA: x3.6, TGFβ1: x1.6, and TIMP1: x1.4). DRs were upregulated, too (Fas/CD95: x9, and TNFR–1: x1.7) and, interestingly, Bcl–2 two-fold and Mcl–1was also 1.4-fold upregulated. Addition of 15µM resveratrol led to further upregulation of these genes (α-SMA: x4.3, TGFβ1: x1.8, TIMP1: x2.2, Fas/CD95: x13, TNFR–1: x2.1, Mcl–1: x2.2 and Bcl2: x3.5). However, in the absence of FFA, resveratrol did not considerably affect the expression of these transcripts. Conclusions: Hepatic stellate cells are activated by the presence of FFA, paralleled by upregulated expression of pro-fibrotic genes, DRs, and the anti-apoptotic proteins. Intriguingly, besides inducing cellular demise, DRs also initiate activation signals. Instead of an expected protective effect, resveratrol aggravated the induction of pro-fibrotic genes while it did not affect such genes in the absence of FFA. Our data thus suggests to reconsider the recommendation of moderate consumption of red wine, at least by obese patients.