Flavonoid extracted from Epimedium attenuate cGAS-STING-mediated diseases by targeting the formation of functional STING signalosome.

Hyperactivation of the cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signalling pathway has been shown to be associated with the development of a variety of inflammatory diseases, and the discovery of an inhibitor of the cGAS-STING signalling pathway holds great promise in the therapeutic interventions. Epimedium flavonoid (EF), a major active ingredient isolated from the medicinal plant Epimedium, has been reported to have good anti-inflammatory activity, but its exact mechanism of action remains unclear. In the present study, we found that EF in mouse bone marrow-derived macrophages (BMDMs), THP-1 (Tohoku Hospital Pediatrics-1) as well as in human peripheral blood mononuclear cells (hPBMC) inhibited the activation of the cGAS-STING signalling pathway, which subsequently led to a decrease in the expression of type I interferon (IFN-ß, CXCL10 and ISG15) and pro-inflammatory cytokines (IL-6 and TNF-α). Mechanistically, EF does not affect STING oligomerization, but inhibits the formation of functional STING signalosome by attenuating the interaction of interferon regulatory factor 3 (IRF3) with STING and TANK-binding kinase 1 (TBK1). Importantly, in vivo experiments, EF has shown promising therapeutic effects on inflammatory diseases mediated by the cGAS-STING pathway, which include the agonist model induced by DMXAA stimulation, the autoimmune inflammatory disease model induced by three prime repair exonuclease 1 (Trex1) deficiency, and the non-alcoholic steatohepatitis (NASH) model induced by a pathogenic amino acid and choline deficiency diet (MCD). To summarize, our study suggests that EF is a potent potential inhibitor component of the cGAS-STING signalling pathway for the treatment of inflammatory diseases mediated by the cGAS-STING signalling pathway.

Prediction of biochemical nonresolution in patients with chronic drug-induced liver injury: A large multicenter study.

BACKGROUND AND AIMS: To clarify high-risk factors and develop a nomogram model to predict biochemical resolution or biochemical nonresolution (BNR) in patients with chronic DILI. APPROACH AND RESULTS: Retrospectively, 3655 of 5326 patients with chronic DILI were enrolled from nine participating hospitals, of whom 2866 underwent liver biopsy. All of these patients were followed up for over 1 year and their clinical characteristics were retrieved from electronic medical records. The endpoint was BNR, defined as alanine aminotransferase or aspartate aminotransferase >1.5× upper limit of normal or alkaline phosphatase >1.1× ULN, at 12 months from chronic DILI diagnosis. The noninvasive high-risk factors for BNR identified by multivariable logistic regression were used to establish a nomogram, which was validated in an independent external cohort. Finally, 19.3% (707 of 3655) patients presented with BNR. Histologically, with the increase in liver inflammation grades and fibrosis stages, the proportion of BNR significantly increased. The risk of BNR was increased by 21.3-fold in patients with significant inflammation compared to none or mild inflammation (p < 0.001). Biochemically, aspartate aminotransferase and total bilirubin, platelets, prothrombin time, sex, and age were associated with BNR and incorporated to construct a nomogram model (BNR-6) with a concordance index of 0.824 (95% CI, 0.798-0.849), which was highly consistent with liver histology. These results were successfully validated both in the internal cohort and external cohort. CONCLUSIONS: Significant liver inflammation is a robust predictor associated with biochemical nonresolution. The established BNR-6 model provides an easy-to-use approach to assess the outcome of chronic DILI.

Liuweiwuling Tablet relieves the inflammatory transformation of hepatocellular carcinoma by inhibiting the PI3K/AKT/NF-κB signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Liuweiwuling Tablet (LWWL) is a patented Chinese medicine approved by the Chinese National Medical Products Administration (NMPA). Clinically, it is used to treat a range of liver diseases that precede hepatocellular carcinoma (HCC), including hepatitis, liver fibrosis and cirrhosis. LWWL is hypothesized to inhibit the inflammatory transformation of HCC, which may have a positive impact on the prevention and treatment of HCC. However, its exact mechanism of action remains unknown. AIM OF THE STUDY: To investigate how LWWL is effective in the treatment of HCC and to validate the pathways involved in this process. MATERIALS AND METHODS: An in vivo model of HCC induced by diethylnitrosamine (DEN) was established to study the effect of LWWL on the development of HCC. The rat serum was analyzed for aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl transpeptidase (γ-GT). The rat liver tissues were stained with hematoxylin and eosin (HE) and Masson's trichrome for pathological analysis. Rat liver tissue was subjected to transcriptome sequencing. Expression of inflammatory and liver fibrosis-related factors in bone marrow-derived macrophages (BMDMs) and LX-2 cells was detected by QRT-PCR, ELISA and Western blot (WB). The expression of apoptosis and stemness genes in HepG2 and Huh7 cells was assessed through flow cytometry and QRT-PCR. Transcriptomics, network pharmacology, WB, and QRT-PCR were employed to validate the mechanisms associated with the amelioration of HCC development by LWWL. RESULTS: LWWL significantly reduced the severity of hepatitis and liver fibrosis, the expression of tumor stemness genes, and the incidence of HCC. In addition, LWWL inhibited the release of inflammatory substances and nuclear accumulation of P65 protein in BMDMs as well as the conversion of LX-2 cells to fibroblasts. LWWL inhibited the proliferation of HepG2 and Huh7 cells, including the initiation of apoptosis and the reduction of stemness gene expression. Importantly, LWWL regulates the PI3K/AKT/NF-κB pathway, which affects hepatic inflammation and cancer progression. CONCLUSION: LWWL inhibited the occurrence and development of HCC by modulating the severity of hepatitis and liver fibrosis, indicating the potential clinical relevance of LWWL in preventing and treating HCC.

Total glucosides of paeony alleviates cGAS-STING-mediated diseases by blocking the STING-IRF3 interaction.

In the realm of autoimmune and inflammatory diseases, the cyclic GMP-AMP synthase (cGAS) stimulator of interferon genes (STING) signaling pathway has been thoroughly investigated and established. Despite this, the clinical approval of drugs targeting the cGAS-STING pathway has been limited. The Total glucosides of paeony (TGP) is highly anti-inflammatory and is commonly used in the treatment of rheumatoid arthritis (RA), emerged as a subject of our study. We found that the TGP markedly reduced the activation of the cGAS-STING signaling pathway, triggered by various cGAS-STING agonists, in mouse bone marrow-derived macrophages (BMDMs) and Tohoku Hospital Pediatrics-1 (THP-1) cells. This inhibition was noted alongside the suppression of interferon regulatory factor 3 (IRF3) phosphorylation and the expression of interferon-beta (IFN-ß), C-X-C motif chemokine ligand 10 (CXCL10), and inflammatory mediators such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). The mechanism of action appeared to involve the TGP's attenuation of the STING-IRF3 interaction, without affecting STING oligomerization, thereby inhibiting the activation of downstream signaling pathways. In vivo, the TGP hindered the initiation of the cGAS-STING pathway by the STING agonist dimethylxanthenone-4-acetic acid (DMXAA) and exhibited promising therapeutic effects in a model of acute liver injury induced by lipopolysaccharide (LPS) and D-galactosamine (D-GalN). Our findings underscore the potential of the TGP as an effective inhibitor of the cGAS-STING pathway, offering a new treatment avenue for inflammatory and autoimmune diseases mediated by this pathway.