Sclareol attenuates liver fibrosis through SENP1-mediated VEGFR2 SUMOylation and inhibition of downstream STAT3 signaling.

Liver fibrosis is a key global health care burden. Sclareol, isolated from Salvia sclarea, possesses various biological activities. Its effect on liver fibrosis remains unknown. This study was proposed to evaluate the antifibrotic activity of sclareol (SCL) and explore its underlying mechanisms. Stimulated hepatic stellate cells served as an in vitro liver fibrosis model. The expression of fibrotic markers was assessed by western blot and real-time PCR. Two classical animal models, bile duct-ligated rats and carbon tetrachloride-treated mice, were utilized for the in vivo experiments. The liver function and fibrosis degree were determined by serum biochemical and histopathological analyses. VEGFR2 SUMOylation was analyzed using coimmunoprecipitation assay. Our results indicated that SCL treatment restricted the profibrotic propensity of activated HSCs. In fibrotic rodents, SCL administration alleviated hepatic injury and reduced collagen accumulation. Mechanistic studies indicated that SCL downregulated the protein level of SENP1 and enhanced VEGFR2 SUMOylation in LX-2 cells, which affected its intracellular trafficking. Blockade of the interaction between VEGFR2 and STAT3 was observed, resulting in the suppression of downstream STAT3 phosphorylation. Our findings demonstrated that SCL has therapeutic efficacy against liver fibrosis through mediating VEGFR2 SUMOylation, suggesting that SCL may be a potential candidate compound for its treatment.

Paeoniflorin-free subfraction of Paeonia lactiflora Pall. shows the potential of anti-hepatic fibrosis: an integrated analysis of network pharmacology and experimental validation.

ETHNOPHARMACOLOGICAL RELEVANCE: Hepatic fibrosis is a major consequence of liver disease. Radix Paeoniae Rubra (RPR), the dry root of Paeonia lactiflora Pall., has a long history of clinical application in traditional Chinese medicine (TCM) for the treatment of liver diseases. The researches of RPR active ingredients are mainly focused on paeoniflorin. However, the functional roles of other ingredients have not been clarified sufficiently in the treatment of hepatic fibrosis with RPR. AIM OF THE STUDY: This study was to figure out the anti-hepatic fibrosis potential and mechanisms of CS-4, one of the paeoniflorin-free subfraction of RPR. MATERIALS AND METHODS: With the guide of bioassay, CS-4, a subfraction of RPR showed in vitro inhibition of hepatic stellate cell activation, was obtained using multiple chromatographic techniques. Its ingredients were determined by UPLC-Q-TOF-MS/MS. Then, the target profiles of ingredients were obtained from the HERB database, and the disease targets were collected from the DisGeNET database. Through the network pharmacology method, a protein-protein interaction network of CS-4 against hepatic fibrosis was established to analyze and excavate the potential therapeutic targets. Combined with the KEGG analysis, a series of signaling pathways were obtained, thereby validated by western blot analysis. RESULTS: The paeoniflorin-free subfraction of RPR, CS-4, was obtained and showed the most potential anti-fibrotic effect in vitro. A total of 20 main ingredients were identified from CS-4 and considered as its active ingredients. From HERB and DisGeNET databases, 1460 potential targets of CS-4 and 1180 disease targets were obtained, respectively. The overlapped 79 targets were considered to exert the potential anti-fibrosis effect of CS-4, such as JAK2, MYC, SMAD3, and IFNG. The gene enrichment analysis revealed that classical TGF-ß/Smad signaling pathway and nonclassical TGF-ß/PI3K-AKT signaling pathway may be two of the main mechanisms of CS-4 against hepatic fibrosis, which supported by western blot analysis. CONCLUSION: In this study, a paeoniflorin-free subfraction with potential anti-hepatic fibrosis activity in vitro, CS-4, was obtained from RPR. Its multiple ingredients, multiple targets, and multiple mechanisms against hepatic fibrosis were explained by network pharmacology and verified by western blot analysis to further support the clinical applications of RPR.

The anti-hepatic fibrosis effects of dihydrotanshinone I are mediated by disrupting the yes-associated protein and transcriptional enhancer factor D2 complex and stimulating autophagy.

BACKGROUND AND PURPOSE: Dihydrotanshinone I (DHI), a lipophilic component of traditional Chinese medicine Salvia miltiorrhiza Bunge, has various therapeutic effects. We investigated the anti-fibrotic effect of DHI and its underlying mechanisms in vitro and in vivo. EXPERIMENTAL APPROACH: Rats subjected to bile duct ligation (BDL) were treated with DHI (25 mg·kg-1 ·day-1 , i.p.) for 14 days. Serum biochemical and liver tissue morphological analyses were performed. The human hepatic stellate cell line LX-2 served as a liver fibrosis model in vitro. Liver fibrogenic genes, yes-associated protein (YAP) downstream genes and autophagy markers were examined using western blot and real-time PCR analyses. Similar analyses were done in rat primary hepatic stellate cells (pHSCs). Autophagy flux was assessed by immunofluorescence. KEY RESULTS: In BDL rats, DHI administration attenuated liver necrosis, bile duct proliferation and collagen accumulation and reduced the expression of genes associated with fibrogenesis, including Tgfb1, Mmp-2, Acta2 and Col1a1. DHI (1, 5, 10 µmol·L-1 ) time- and dose-dependently suppressed the protein level of COL1A1, TGFß1 and α-SMA in LX-2 cells and rat pHSCs. Furthermore, DHI blocked the nuclear translocation of YAP, which inhibited the YAP/TEAD2 interaction and its downstream fibrogenic genes, connective tissue growth factor, SOX4 and survivin. This stimulated autophagic flux and accelerated the degradation of liver collagen. CONCLUSIONS AND IMPLICATIONS: DHI exerts anti-fibrotic effects in BDL rats, LX-2 cells and rat pHSCs by inhibiting the YAP and TEAD2 complex and stimulating autophagy. These findings indicate that DHI may be a potential therapeutic for the treatment of liver fibrosis.