The effect of antifibrotic drug halofugine on Th17 cells in concanavalin A-induced liver fibrosis

Metabolomic Profiling and Network Toxicology: Mechanistic Insights into Effect of Gossypol Acetate Isomers in Uterine Fibroids and Liver Injury

OBJECTIVE

Gossypol is a natural polyphenolic dialdehyde product that is primarily isolated from cottonseed. It is a racemized mixture of (-)-gossypol and (+)-gossypol that has anti-infection, antimalarial, antiviral, antifertility, antitumor and antioxidant activities, among others. Gossypol optical isomers have been reported to differ in their biological activities and toxic effects.

METHOD

In this study, we performed a metabolomics analysis of rat serum using 1H-NMR technology to investigate gossypol optical isomers' mechanism of action on uterine fibroids. Network toxicology was used to explore the mechanism of the liver injury caused by gossypol optical isomers. SD rats were randomly divided into a normal control group; model control group; a drug-positive group (compound gossypol acetate tablets); high-, medium- and low-dose (-)-gossypol acetate groups; and high-, medium- and low-dose (+)-gossypol acetate groups.

RESULT

Serum metabolomics showed that gossypol optical isomers' pharmacodynamic effect on rats' uterine fibroids affected their lactic acid, cholesterol, leucine, alanine, glutamate, glutamine, arginine, proline, glucose, etc. According to network toxicology, the targets of the liver injury caused by gossypol optical isomers included HSP90AA1, SRC, MAPK1, AKT1, EGFR, BCL2, CASP3, etc. KEGG enrichment showed that the toxicity mechanism may be related to pathways active in cancer, such as the PPAR signaling pathway, glycolysis/glycolysis gluconeogenesis, Th17 cell differentiation, and 91 other closely related signaling pathways.

CONCLUSIONS

(-)-gossypol acetate and (+)-gossypol acetate play positive roles in the treatment and prevention of uterine fibroids. Gossypol optical isomers cause liver damage through multiple targets and pathways.

Pathogenic Th17 cell-mediated liver fibrosis contributes to resistance to PD-L1 antibody immunotherapy in hepatocellular carcinoma

Understanding the mechanisms of resistance of hepatocellular carcinoma (HCC) to targeted therapies and immune checkpoint blockade is critical for the development of new combination therapies and improving patient survival. Here, we found that in HCC, anti-programmed cell death 1 ligand 1 (PD-L1) therapy reduces liver cancer growth, but the tumors eventually become resistant to continued therapy. Experimental analyses shows that the infiltration of pathogenic T helper 17 (pTh17) cells increases in drug-resistant HCC, and pTh17 cells secrete interleukin-17A (IL-17A), which promotes the expression of PD-L1 on the surface of HCC cells and produces resistance to anti-PD-L1 therapy. Anti-IL-17A combined with PD-L1 blockade significantly increased the infiltration of cytotoxic CD8+ T cells expressing high levels of interferon-γ and reduced treatment resistance in HCC. These results support the combination of anti-PD-L1 and anti-IL-17A as a novel strategy to induce effective T cell-mediated anti-tumor immune responses.

A Perspective Of Intestinal Immune-Microbiome Interactions In Alcohol-Associated Liver Disease

Uncovering the intricacies of the gut microbiome and how it interacts with the host immune system has opened up pathways in the search for the treatment of disease conditions. Alcohol-associated liver disease is a major cause of death worldwide. Research has shed light on the breakdown of the protective gut barriers, translocation of gut microbes to the liver and inflammatory immune response to microbes all contributing to alcohol-associated liver disease. This knowledge has opened up avenues for alternative therapies to alleviate alcohol-associated liver disease based on the interaction of the commensal gut microbiome as a key player in the regulation of the immune response. This review describes the relevance of the intestinal immune system, the gut microbiota, and specialized and non-specialized intestinal cells in the regulation of intestinal homeostasis. It also reflects how these components are altered during alcohol-associated liver disease and discusses new approaches for potential future therapies in alcohol-associated liver disease.

The Roles of Immune Cells in the Pathogenesis of Fibrosis

Tissue injury and inflammatory response trigger the development of fibrosis in various diseases. It has been recognized that both innate and adaptive immune cells are important players with multifaceted functions in fibrogenesis. The activated immune cells produce various cytokines, modulate the differentiation and functions of myofibroblasts via diverse molecular mechanisms, and regulate fibrotic development. The immune cells exhibit differential functions during different stages of fibrotic diseases. In this review, we summarized recent advances in understanding the roles of immune cells in regulating fibrotic development and immune-based therapies in different disorders and discuss the underlying molecular mechanisms with a focus on mTOR and JAK-STAT signaling pathways.

Huagan tongluo Fang improves liver fibrosis via down-regulating miR-184 and up-regulating FOXO1 to inhibit Th17 cell differentiation

BACKGROUND

The purpose of this research is to reveal the improvement effect and potential mechanism of Huagan tongluo Fang (HGTLF) on liver fibrosis.

METHODS

A mouse model of liver fibrosis induced by CCl₄ was established to analyze the effect of HGTLF on liver fibrosis. The expression changes of miRNA after HGTLF stimulation were detected by qRT-PCR. After interference with miR-184 in Th17 cells, the concentration of IL-17A in cell culture supernatants was detected by ELISA and the proportion of Th17 cells was analyzed by flow cytometry. The relationship between miR-184 and FOXO1 was verified by online software and dual-luciferase reporter system. After HGTLF treatment of Th17 cells overexpressing miR-184, the protein level of FOXO1 was detected by Western blot.

RESULTS

HGTLF could significantly improve liver fibrosis in mice. By qRT-PCR, miR-184 was most significantly expressed after HGTLF drug stimulation, and miR-184 was considered to be the major RNA involved in Th17 cell differentiation. Interference with miR-184 in Th17 cells inhibited the differentiation of Th17 cells. By online software and dual-luciferase reporter system assay, the direct interaction of miR-184 with FOXO1 was confirmed. After HGTLF treatment of Th17 cells overexpressing miR-184, FOXO1 protein levels were significantly up-regulated and inhibited the differentiation of Th17 cells, which was reversed by miR-184 inhibitors. The Vivo experiments also confirmed the improvement effect of HGTLF on liver fibrosis in mice.

CONCLUSION

Our results indicated that HGTLF could improve liver fibrosis via down-regulating miR-184 and up-regulating of FOXO1 to inhibit Th17 cell differentiation.

Effect of Th9/IL-9 on the growth of gastric cancer in nude mice

Objective

By neutralizing IL-9 in a nude mouse model, the study aimed to investigate the role of Th9/IL-9 on the growth of gastric cancer in mice.

Materials and methods

Male BALB/c nude mice were randomly divided into three groups: a normal control group (Control), an SGC-7901 xenografted nude mice model group (Model), and a rIL-9 treatment group (Treat). The weight of the tumors was recorded to calculate the tumor inhibition rate. Flow cytometry was used to detect the cell frequency of Th9, Th17, and Treg in peripheral blood. The IL-4, IL-9, IL-10, IL-25, VEGF, and TGF-β levels in serum were determined by ELISA. The cellular migration and invasion were investigated by transwell assay. Immunohistochemical and Western blot were used to detect the expression of IL-9, CD34, PU.1, p53, and p21 proteins in gastric cancer tissue. The mRNA expression levels of IL-9, IL-21, and PU.1 in gastric cancer tissue were determined by qRT-PCR.

Result

rIL-9 can significantly inhibit the growth of gastric cancer. The frequency of Th9, Th17, and Treg in peripheral blood was decreased upon treatment. The levels of IL-4, IL-9, IL-10, IL-25, VEGF, and TGF-β in serum were significantly reduced in the Treat group compared with the Model group (P<0.05). rIL-9 can inhibit cellular migration and invasion and reduce the mRNA level of IL-9, IL-21, and PU.1. Meanwhile, in the Treat group, the expression of IL-9, CD34, and PU.1 was significantly reduced, whereas the expression of p53 and p21 was significantly increased compared with the Model group (P<0.05).

Conclusion

This study suggested that Th9/IL-9 has a deleterious role in gastric cancer.

Splenectomy Promotes Macrophage Polarization in a Mouse Model of Concanavalin A- (ConA-) Induced Liver Fibrosis

Background

Splenectomy can improve liver function and survival in patients with autoimmune hepatitis (AIH) and liver cirrhosis. We investigated the underlying mechanism in a mouse model of concanavalin A- (ConA-) induced liver fibrosis.

Methods

We used ConA to induce immune liver fibrosis in BALB/c mice. Splenectomy was performed alone or with the administration of dexamethasone (DEX). Changes in blood and liver tissues were evaluated.

Results

Mice treated with ConA for 7 weeks developed advanced liver fibrosis, while splenectomy suppressed liver fibrosis. Although the populations of macrophages/monocytes and M1 macrophages decreased after splenectomy, the inflammatory factors associated with M2 macrophages increased after splenectomy. Furthermore, the population of circulating CD11b⁺Ly6C^high myeloid-derived suppressor cells (MDSCs) increased after splenectomy. After ConA treatment, elevated levels of activated and total NF-kBp65/p50 combined with DNA were observed in hepatic tissues. In contrast, the levels of NF-κB p65/p50 decreased after splenectomy.

Conclusions

Splenectomy may promote the polarization of CD11b⁺Ly6C^high MDSCs and the differentiation of M2 macrophages while restricting the level of NF-κB p65-p50 heterodimers. These factors may suppress the progression of liver fibrosis.

Halofuginone ameliorates inflammation in severe acute hepatitis B virus (HBV)-infected SD rats through AMPK activation

The hepatitis B virus (HBV) has caused acute and chronic liver diseases in ~350 million infected people worldwide. Halofuginone (HF) is a plant alkaloid which has been demonstrated to play a crucial role in immune regulation. Our present study explored the function of HF in the immune response of HBV-infected Sprague Dawley (SD) rats. Plasmid containing pCDNA3.1-HBV1.3 was injected in SD rats for the construction of an acute HBV-infected animal model. Our data showed that HF reduced the high concentrations of serum hepatitis B e-antigen, hepatitis B surface antigen, and HBV DNA induced by HBV infection. HF also reduced the number of T helper (Th)17 cells and the expression of interleukin (IL)-17 compared with the pCDNA3.1-HBV1.3 group. Moreover, pro-inflammatory cytokine levels (IL-17, IL-23, interferon-γ, and IL-2) were downregulated and anti-inflammatory cytokine levels (IL-4 and IL-13) were upregulated by HF. Through further research we found that the expression of AMP-activated protein kinase (AMPK) and IKBA which suppressed NF-κB activation was increased while the expression of p-NF-κB P65 was decreased in pCDNA3.1-HBV1.3+HF group compared with pCDNA3.1-HBV1.3 group, indicating that HF may work through the activation of AMPK. Finally, our conjecture was further verified by using the AMPK inhibitor compound C, which counteracted the anti-inflammation effect of HF, resulting in the decreased expression of AMPK, IKBA and increased expression of p-NF-κB P65 and reduced number of Th17 cells. In our present study, HF was considered as an anti-inflammatory factor in acute HBV-infected SD rats and worked through AMPK-mediated NF-κB p65 inactivation. This study implicated HF as a potential therapeutic strategy for hepatitis B.

Immunity and Fibrogenesis: The Role of Th17/IL-17 Axis in HBV and HCV-induced Chronic Hepatitis and Progression to Cirrhosis

Cirrhosis is a common final pathway for most chronic liver diseases; representing an increasing burden worldwide and is associated with increased morbidity and mortality. Current evidence has shown that, after an initial injury, the immune response has a significant participation in the ongoing damage, and progression from chronic viral hepatitis (CVH) to cirrhosis, driving the activation and maintenance of main fibrogenic pathways. Among immune deregulations, those related to the subtype 17 of T helper lymphocytes (Th17)/interleukin-17 (IL-17) axis have been recognized as key immunopathological and prognostic elements in patients with CVH. The Th17/IL-17 axis has been found involved in several points of fibrogenesis chain from the activation of stellate cells, increased expression of profibrotic factors as TGF-β, promotion of the myofibroblastic or epithelial–mesenchymal transition, stimulation of the synthesis of collagen, and induction of imbalance between matrix metalloproteinases and tissue inhibitors of metalloproteinases (TIMPs). It also promotes the recruitment of inflammatory cells and increases the expression of proinflammatory cytokines such as IL-6 and IL-23. So, the Th17/IL-17 axis is simultaneously the fuel and the flame of a sustained proinflammatory and profibrotic environment. This work aims to present the immunopathologic and prognostic role of the Th17/IL-17 axis and related pathways in fibrogenesis and progression to cirrhosis in patients with liver disease due to hepatitis B virus (HBV) and hepatitis C virus (HCV).

Notch signaling mediated by TGF-β/Smad pathway in concanavalin A-induced liver fibrosis in rats

AIM

To explore the exact interaction between Notch and transforming growth factor (TGF)-β signaling in liver fibrosis.

METHODS

We established a rat model of liver fibrosis induced by concanavalin A. Peripheral blood mononuclear cells (PBMCs) were isolated from the modeled rats, and cultured with γ-secretase inhibitor DAPT and TGF-β inhibitor for 24 h. The mRNA levels of Notch and TGF-β signaling were detected by quantitative real-time polymerase chain reaction. Expression of Notch and TGF-β proteins was analyzed by western blotting.

RESULTS

Compared to control rats, Notch and TGF-β signaling was activated in PBMCs of model rats. Administration of DAPT and TGF-β inhibitor suppressed Notch and TGF-β signal transducer in PBMCs of model rats. DAPT reduced mRNA and protein expression of TGF-β signaling, such as TGF-β1 and Smad3. TGF-β inhibitor also downregulated Notch1, Hes1 and Hes5, and mRNA and protein expression of the Notch signaling pathway.

CONCLUSION

Notch and TGF-β signaling play a role in liver fibrosis. TGF-β signaling upregulates Notch signaling, which promotes TGF-β signaling.

Antifibrotic mechanism of deferoxamine in concanavalin A induced-liver fibrosis: Impact on interferon therapy

Iron-overload is a well-known factor of hepatotoxicity and liver fibrosis, which found to be a common finding among hepatitis C virus patients and related to interferon resistance. We aimed to elucidate the potential antifibrotic effect of deferoxamine; the main iron chelator, and its additional usefulness to interferon-based therapy in concanavalin A-induced immunological model of liver fibrosis. Rats were treated with deferoxamine and/or pegylated interferon-α for 6 weeks. Hepatotoxicity indices, oxidative stress, inflammatory and liver fibrosis markers were assessed. Concanavalin A induced a significant increase in hepatotoxicity indices and lipid peroxidation accompanied with a significant depletion of total antioxidant capacity, glutathione level and superoxide dismutase activity. Besides, it increased CD4(+) T-cells content and the downstream inflammatory cascades, including NF-κB, TNF-α, iNOS, COX-2, IL-6 and IFN-γ. Furthermore, α-SMA, TGF-β1 and hydroxyproline were increased markedly, which confirmed by histopathology. Treatment with either deferoxamine or pegylated interferon-α alone reduced liver fibrosis markers significantly and improved liver histology. However, some of the hepatotoxicity indices and oxidative stress markers did not improve upon pegylated interferon-α treatment alone, besides the remarkable increase in IL-6. Combination therapy of deferoxamine with pegylated interferon-α further improved all previous markers, ameliorated IL-6 elevation, as well as increased hepcidin expression. In conclusion, our study provides evidences for the potent antifibrotic effects of deferoxamine and the underlying mechanisms that involved attenuating oxidative stress and subsequent inflammatory cascade, as well as the production of profibrogenic factors. Addition of deferoxamine to interferon regimen for HCV patients may offer a promising adjuvant modality to enhance therapeutic response.

Aqueous Date Flesh or Pits Extract Attenuates Liver Fibrosis via Suppression of Hepatic Stellate Cell Activation and Reduction of Inflammatory Cytokines, Transforming Growth Factor- β 1 and Angiogenic Markers in Carbon Tetrachloride-Intoxicated Rats

Previous data indicated the protective effect of date fruit extract on oxidative damage in rat liver. However, the hepatoprotective effects via other mechanisms have not been investigated. This study was performed to evaluate the antifibrotic effect of date flesh extract (DFE) or date pits extract (DPE) via inactivation of hepatic stellate cells (HSCs), reducing the levels of inflammatory, fibrotic and angiogenic markers. Coffee was used as reference hepatoprotective agent. Liver fibrosis was induced by injection of CCl₄ (0.4 mL/kg) three times weekly for 8 weeks. DFE, DPE (6 mL/kg), coffee (300 mg/kg), and combination of coffee + DFE and coffee + DPE were given to CCl₄-intoxicated rats daily for 8 weeks. DFE, DPE, and their combination with coffee attenuated the elevated levels of inflammatory cytokines including tumor necrosis factor-α, interleukin-6, and interleukin-1β. The increased levels of transforming growth factor-β1 and collagen deposition in injured liver were alleviated by both extracts. CCl₄-induced expression of α-smooth muscle actin was suppressed indicating HSCs inactivation. Increased angiogenesis was ameliorated as revealed by reduced levels and expression of vascular endothelial growth factor and CD31. We concluded that DFE or DPE could protect liver via different mechanisms. The combination of coffee with DFE or DPE may enhance its antifibrotic effects.

Halofuginone - the multifaceted molecule

Halofuginone is an analog of febrifugine-an alkaloid originally isolated from the plant Dichroa febrifuga. During recent years, halofuginone has attracted much attention because of its wide range of beneficial biological activities, which encompass malaria, cancer, and fibrosis-related and autoimmune diseases. At present two modes of halofuginone actions have been described: (1) Inhibition of Smad3 phosphorylation downstream of the TGFβ signaling pathway results in inhibition of fibroblasts-to-myofibroblasts transition and fibrosis. (2) Inhibition of prolyl-tRNA synthetase (ProRS) activity in the blood stage of malaria and inhibition of Th17 cell differentiation thereby inhibiting inflammation and the autoimmune reaction by activation of the amino acid starvation and integrated stress responses. This review deals with the history and origin of this natural product, its synthesis, its known modes of action, and it's various biological activities in pre-clinical animal models and in humans.