Rosiglitazone ameliorates bile duct ligation-induced liver fibrosis by down-regulating NF-κB-TNF-α signaling pathway in a PPARγ-dependent manner

The cyclin-dependent kinase inhibitor abemaciclib-induced hepatotoxicity: Insight on the molecular mechanisms in HepG2/THP-1 co-culture model

Drug-induced liver injury (DILI) is one of the widespread causes of liver injury and immune system plays important role. Abemaciclib (ABE) is a cyclin-dependent kinase inhibitor used as monotherapy or combination therapy in the treatment of breast cancer. Like other kinase inhibitors, the underlying mechanisms of ABE-induced hepatotoxicity are not completely known yet. In the current study, hepatotoxicity of ABE was evaluated with HepG2/THP-1 co-culture model which has been developed in recent years for the evaluation of DILI potential. Following ABE treatment, oxidative stress, mitochondrial damage, cytokine secretion levels, apoptotic/necrotic cell death were determined. According to our results, ROS production along with GSH depletion was observed in HepG2 cells after ABE treatment. ABE promoted secretion of pro-inflammatory mediators (TNF-α and MCP-1) and declined anti-inflammatory cytokine IL-10 release. Besides, NFKβ and JNK1 protein expression levels increased following ABE treatment. ABE enhanced intracellular calcium levels, induced early apoptotic and necrotic cell deaths in HepG2 cells. Furthermore, the changes in some mitochondrial parameters including a reducement in intracellular ATP levels and complex V activity; hyperpolarized mitochondrial membrane potential and enhanced mitochondrial ROS levels were observed, whereas mitochondrial mass did not show any differences after ABE treatments. Therefore, ABE-induced hepatotoxic effects is probably via oxidative stress, inflammatory response and necrotic cell death rather than direct mitochondrial toxicity. In conclusion; the study makes a significant contribution to strengthening the infrastructure we have on in vitro toxicity mechanism evaluations, which are the basis of preclinical toxicity studies.

Current investigations for liver fibrosis treatment: between repurposing the FDA-approved drugs and the other emerging approaches

Long-term liver injuries lead to hepatic fibrosis, often progressing into cirrhosis, liver failure, portal hypertension, and hepatocellular carcinoma. There is currently no effective therapy available for liver fibrosis. Thus, continuous investigations for anti-fibrotic therapy are ongoing. The main theme of anti-fibrotic investigation during recent years is the rationale-based selection of treatment molecules according to the current understanding of the pathology of the disease. The research efforts are mainly toward repurposing current FDA-approved drugs targeting etiological molecular factors involved in developing liver fibrosis. In parallel, investigations also focus on experimental small molecules with evidence to hinder or reverse the fibrosis. Natural compounds, immunological, and genetic approaches have shown significant encouraging effects. This review summarizes the efficacy and safety of current under-investigation antifibrosis medications targeting various molecular targets, as well as the properties of antifibrosis medications, mainly in phase II and III clinical trials.

ACSL4 inhibition prevents macrophage ferroptosis and alleviates fibrosis in bleomycin-induced systemic sclerosis model

BACKGROUND

Systemic sclerosis (SSc), with unclear pathophysiology, is a paradigmatic rheumatic disease of immunity dysfunction-driven multi-organ inflammation and ultimate fibrosis. Pathogenesis breakthroughs are urgently needed for available treatments halting its unremitting stiffness. This study aims to investigate whether ferroptosis can regulate the progressive SSc fibrosis.

METHODS

In vivo, bleomycin (BLM)-induced mice model was subjected to ferroptosis detection using western blotting, malondialdehyde (MDA), and glutathione (GSH) assays. Pharmacological inhibitor of the acyl-CoA synthetase long-chain family member 4 (ACSL4) was utilized to explore its potential therapeutic effects for fibrosis, from histological, biochemical, and molecular analyses. In vitro, bone marrow-derived macrophages (BMDM) were activated into inflammatory phenotype and then the relationship was evaluated between activation level and ferroptosis sensitivity in lipopolysaccharide (LPS) incubation with gradient concentrations. The potential calpain/ACSL4 axis was analyzed after calpain knockdown or over-expression in Raw264.7.

RESULTS

Both skin and lung tissue ferroptosis were present in SSc mice with enhanced ACSL4 expression, while ACSL4 inhibition effectively halted fibrosis progressing and provides protection from inflammatory milieu. Meanwhile, a positive regulation relationship between LPS-induced macrophage activity and ferroptosis sensitivity can be observed. After calpain knockdown, both inflammatory macrophage ferroptosis sensitivity and ACSL4 expression decreased, while its over-expression renders ACSL4-envoking condition. Also, calpain pharmacological inhibition reduced both ferroptosis and fibrosis aptitude in mice.

CONCLUSIONS

ACSL4 induces inflammatory macrophage ferroptosis to aggravate fibrosis progressing. ACSL4 and its upregulators of calpains may be potential therapeutic targets for BLM model of SSc.

A herbal product inhibits carbon tetrachloride-induced liver fibrosis by suppressing the epidermal growth factor receptor signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Fuzheng Huayu formula (FZHY), composed of Salvia miltiorrhiza Bunge, Cordyceps sinensis, the seed of Prunus persica (L.) Batsch, the pollen of Pinus massoniana Lamb, Gynostemma pentaphyllum (Thunb.) Makino and the fruit of Schisandra chinensis (Turcz.) Baill, is a Chinese herbal compound with demonstrated clinical benefits in liver fibrosis (LF). However, its potential mechanism and molecular targets remain to be elucidated.

AIM OF THE STUDY

This study was designed to evaluate the anti-fibrotic role of FZHY in hepatic fibrosis and to elucidate the potential mechanisms.

MATERIALS AND METHODS

Network pharmacology was assayed to identify the interrelationships among compounds of FZHY, potential targets and putative pathways on anti-LF. Then the core pharmaceutical target for FZHY against LF was verified by serum proteomic analysis. Further in vivo and in vitro assays were performed to verify the prediction of the pharmaceutical network.

RESULTS

The network pharmacology analysis revealed that a total of 175 FZHY-LF crossover proteins were filtered into a protein-protein interaction (PPI) network complex and designated as the potential targets of FZHY against LF, and the Epidermal Growth Factor Receptor (EGFR) signaling pathway was further explored according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Then analytical studies were validated by carbon tetrachloride (CCl₄)-induced model in vivo. We found FZHY could attenuate CCl₄-induced LF, especially decrease p-EGFR expression in α-Smooth Muscle Actin (α-SMA)-positive hepatic stellate cell (HSC) and inhibit the downstream of the EGFR signaling pathway, especially Extracellular Regulated Protein Kinases (ERK) signaling pathway in liver tissue. We further demonstrate that FZHY could inhibit Epidermal Growth Factor (EGF)-induced HSC activation, as well as the expression of p-EGFR and the key protein of the ERK signaling pathway.

CONCLUSIONS

FZHY has a good effect against CCl₄-induced LF. The action mechanism was associated with the down-regulation of the EGFR signaling pathway in activated HSCs.

Stingless Bee (Heterotrigona Itama) Honey and Its Phenolic-Rich Extract Ameliorate Oxidant-Antioxidant Balance via KEAP1-NRF2 Signalling Pathway

Diabetes is associated with an imbalance between oxidants and antioxidants, leading to oxidative stress. This imbalance contributes to the development and progression of diabetic complications. Similarly, renal and liver diseases are characterised by oxidative stress, where an excess of oxidants overwhelms the antioxidant defense mechanisms, causing tissue damage and dysfunction. Restoring the oxidant-antioxidant balance is essential for mitigating oxidative stress-related damage under these conditions. In this current study, the efficacy of stingless bee honey (SBH) and its phenolic-rich extract (PRE) in controlling the oxidant-antioxidant balance in high-fat diet- and streptozotocin/nicotinamide-induced diabetic rats was investigated. The administration of SBH and PRE improved systemic antioxidant defense and oxidative stress-related measures without compromising liver and renal functioning. Analyses of the liver, skeletal muscle and adipose tissues revealed differences in their capacities to scavenge free radicals and halt lipid peroxidation. Transcriptional alterations hypothesised tissue-specific control of KEAP1-NRF2 signalling by upregulation of Nrf2, Ho1 and Sod1 in a tissue-specific manner. In addition, hepatic translational studies demonstrated the stimulation of downstream antioxidant-related protein with upregulated expression of SOD-1 and HOD-1 protein. Overall, the results indicated that PRE and SBH can be exploited to restore the oxidant-antioxidant imbalance generated by diabetes via regulating the KEAP1-NRF2 signalling pathway.

Peroxisome proliferator-activated receptor γ activation ameliorates liver fibrosis-differential action of transcription factor EB and autophagy on hepatocytes and stellate cells

BACKGROUND

Peroxisome proliferator-activated receptor γ (PPARγ) activation suppresses HSC activation and liver fibrosis. Moreover, autophagy is implicated in hepatic lipid metabolism. Here, we determined whether PPARγ activation ameliorates HSC activation by downregulating transcription factor EB (TFEB)-mediated autophagy.

METHODS AND RESULTS

Atg7 or Tfeb knockdown in human HSC line LX-2 cells downregulated the expression of fibrogenic markers including α smooth muscle actin, glial fibrillary acidic protein, and collagen type 1. Conversely, Atg7 or Tfeb overexpression upregulated fibrogenic marker expression. Rosiglitazone (RGZ)-mediated PPARγ activation and/or overexpression in LX-2 cells and primary HSCs decreased autophagy, as indicated by LC3B conversion, total and nuclear-TFEB contents, mRFP-LC3 and BODIPY 493/503 colocalization, and GFP-LC3 and LysoTracker colocalization. RGZ treatment decreased liver fat content, liver enzyme levels, and fibrogenic marker expression in high-fat high-cholesterol diet-fed mice. Electron microscopy showed that RGZ treatment restored the high-fat high-cholesterol diet-mediated lipid droplet decrease and autophagic vesicle induction in primary HSCs and liver tissues. However, TFEB overexpression in LX-2 cells offset the aforementioned effects of RGZ on autophagic flux, lipid droplets, and fibrogenic marker expression.

CONCLUSIONS

Activation of PPARγ with RGZ ameliorated liver fibrosis and downregulation of TFEB and autophagy in HSCs may be important for the antifibrotic effects of PPARγ activation.

Reversal of hepatic fibrosis by the co-delivery of drug and ribonucleoprotein-based genome editor

Liver fibrosis is a chronic disease without effective treatment in the clinic. Gene editing systems such as the well-known CRISPR/Cas9 have shown great potential in the biomedical field. However, the delivery of the ribonucleoprotein is challenging due to the unstable RNA probe and the requirement for the entrance to the nucleus. Recently, a structure-guided endonuclease (SGN) has been reported as an effective gene-editing system composed of a nuclease and stable DNA probes, which can regulate the protein expression by targeting specific mRNA outside the nucleus. Here, we conjugated the SGN to a nanomicelle as the delivery system. In the resulting material, the chance of the collision between the endonuclease and the probe was raised due to the confinement of the two components within the 40-nm nanomicelle, thus the mRNA can be cleaved immediately after being captured by the probe, resulting in a space-induced nucleotide identification-cleavage acceleration effect. The delivery system was used to treat liver fibrosis via the co-delivery of SGN and a drug rosiglitazone to the hepatic stellate cells, which separately downregulated the expression of tissue inhibitor of metalloprotease-1 and inactivated the hepatic stellate cells. The system successfully reversed the liver fibrosis in mice through the bidirectional regulatory that simultaneously promoted the degradation and inhibited the production of the collagen, demonstrating the great potency of the SGN system as gene medicine.

Adipose-derived mesenchymal stem cell-secreted extracellular vesicles alleviate non-alcoholic fatty liver disease via delivering miR-223-3p

Increasing studies have identified the potential of mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) in non-alcoholic fatty liver disease (NAFLD) treatment. Hence, we further focused on the potential of adipose-derived MSC (ADSC)-EVs in NAFLD by delivering miR-223-3p. The uptake of isolated ADSC-EVs by hepatocytes was assessed, and the expression of miR-223-3p in ADSC-EVs and hepatocytes was characterized. It was established that miR-223-3p, enriched in ADSC-EVs, could be delivered by ADSC-EVs into hepatocytes. Using co-culture system and gain-of-function approach, we evaluated the effect of ADSC-EVs carrying miR-223-3p on lipid accumulation and liver fibrosis in pyrrolizidine alkaloids (PA)-induced hepatocytes and a high-fat diet-induced NAFLD mouse model. Bioinformatics websites and dual-luciferase reporter gene assay were performed to determine the interactions between miR-223-3p and E2F1, which was further validated by rescue experiments. ADSC-EVs containing miR-223-3p displayed suppressive effects on lipid accumulation and liver fibrosis through E2F1 inhibition, since E2F1 was demonstrated as a target gene of miR-223-3p. The protective role of ADSC-EVs by delivering miR-223-3p was then confirmed in the mouse model. Collectively, this study elucidated that ADSC-EVs delayed the progression NAFLD through the delivery of anti-fibrotic miR-223-3p and subsequent E2F1 suppression, which may suggest miR-223-3p-loaded ADSC-EVs to be a potential therapeutic approach for NAFLD.

Cannabidiol markedly alleviates skin and liver fibrosis

Cannabidiol (CBD) has been suggested as a potential therapy for inflammatory and fibrotic diseases. Cannabidiol was demonstrated to reduce alcohol-induced liver inflammation and steatosis but its specific activity on the fibrotic process was not investigated. Herein, the antifibrotic effects of cannabidiol in the skin were analysed in vitro using NIH-3T3 fibroblasts and human dermal fibroblasts and in vivo using the bleomycin-induced model of skin fibrosis. In a second model, non-alcoholic liver fibrosis was induced in mice by CCl4 exposure. Cannabidiol was administered daily, intraperitoneally in mice challenged with bleomycin and orally in CCl4 mice, and skin and liver fibrosis and inflammation were assessed by immunochemistry. Cannabidiol inhibited collagen gene transcription and synthesis and prevented TGFβ-and IL-4 induced fibroblast migration. In the bleomycin model, cannabidiol prevented skin fibrosis and collagen accumulation around skin blood vessels, and in the CCl4 model cannabidiol significantly attenuated liver fibrosis measured by picrosirius red and Tenascin C staining and reduced T cell and macrophage infiltration. Altogether, our data further support the rationale of the medicinal use of this cannabinoid, as well as cannabis preparations containing it, in the management of fibrotic diseases including Systemic Sclerosis and Non-Alcoholic Fatty Liver Disease.

MicroRNA-15a inhibits hepatic stellate cell activation and proliferation via targeting SRY-box transcription factor 9

Accumulating research have indicated that microRNAs are associated with the progression of hepatic fibrosis (HF). Nevertheless, the biological role and function of microRNA (miR)-15a in HF are still unknown. Our data revealed that miR-15a expression was decreased in TGF-β1-treated LX-2 cells and CCl₄-induced mouse model. Additionally, miR-15a could directly target the 3’‑untranslated region of SRY-box transcription factor 9 (SOX9) to inhibit its expression. miR-15a overexpression attenuated the viability and invasion, but enhanced apoptosis in LX-2 cells. However, miR-15a knockdown had the opposite effects. Interestingly, SOX9 overexpression reversed the changes in cell viability, invasion and apoptosis mediated by miR-15a overexpression. Moreover, the miR-15a overexpression-mediated collagen I and alpha smooth muscle actin (a-SMA) downregulation were reversed by SOX9 overexpression. Overall, miR-15a could inhibit LX-2 cell viability and HF pathogenesis by targeting SOX9 in vitro and in vivo.

Co-Crystal of Rosiglitazone With Berberine Ameliorates Hyperglycemia and Insulin Resistance Through the PI3K/AKT/TXNIP Pathway In Vivo and In Vitro

Background: Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease characterized by insulin resistance and hyperglycemia. This study examined the effect and elucidated the mechanism of improvement of hyperglycemia and insulin resistance by a co-crystal of rosiglitazone with berberine (RB) in high-sugar high-fat diet (HSHFD)-induced diabetic KKAy mice. Methods: Diabetic KKAy mice were randomly divided into seven groups: KKAy model control group (DM control) treated with 3% sodium carboxymethyl cellulose; RB groups, administered daily with RB 0.7 mg/kg (RB-L), 2.11 mg/kg (RB-M), or 6.33 mg/kg (RB-H); positive control groups, administered daily with rosiglitazone 1.04 mg/kg (RSG), berberine 195 mg/kg (BBR), or combination of 1.04 mg/kg RSG and 1.08 mg/kg BBR (MIX). Test compounds were administered orally for 8 weeks. Non-diabetic C57BL/6J mice were used as normal control (NC). Blood glucose, food intake, body weight, glucose-lipid metabolism, and pathological changes in the pancreas and liver were examined. We further evaluated the mechanism of action of RB in C2C12 and HepG2 cells stimulated with high glucose and palmitate. Results: RB treatment improved glucolipid metabolism and insulin resistance in diabetic KKAy mice. RB reduced blood glucose levels, white fat index, plasma triglyceride (TG), low-density lipoprotein (LDL), gastric inhibitory peptide (GIP), and insulin levels, increased the levels of plasma glucagon-like peptide-1 (GLP-1), high-density lipoprotein (HDL), and glycogen content in the liver and muscle; and improved oral glucose tolerance test (OGTT), insulin tolerance test (ITT), and pathological changes in the pancreas and liver of KKAy mice. Moreover, RB upregulated p-PI3K and p-AKT levels and reduced TXNIP expression in KKAy mice and in HepG2 and C2C12 cells. Conclusion: These data indicate that RB ameliorates insulin resistance and metabolic disorders, and the mechanism might be through regulating the PI3K/AKT/TXNIP signaling pathway . Thus, the co-crystal drug RB may be considered as a potential antidiabetic agent for future clinical therapy.

Schisandrin B regulates macrophage polarization and alleviates liver fibrosis via activation of PPARγ

Background

Schisandrin B (Sch B), the main ingredient of Schisandra chinensis, displays many bioactivities. This study aimed to identify the drug target of Sch B against liver fibrosis and describe the related molecular mechanisms.

Methods

The effects of Sch B on liver fibrosis and macrophage polarization was investigated in vivo and in vitro. Furthermore, we analyzed the regulatory effect of Sch B on peroxisome proliferator-activated receptor gamma (PPARγ).

Results

Our data showed that Sch B dramatically alleviated liver inflammation and fibrosis and inhibited macrophage activation via PPARγ. Sch B binds with PPARγ by molecular docking. Immunofluorescence double staining showed that PPARγ was mainly expressed in macrophages rather than hepatic stellate cells (HSCs) in liver fibrosis. Importantly, Sch B strongly inhibited macrophage polarization in fibrotic livers compared with the model group. Further, the results revealed that Sch B efficiently inhibited macrophage polarization and also decreased the levels of inflammatory cytokines in vitro. Knockdown of PPARγ by small interfering RNA (siRNA) inhibited the effect of Sch B on macrophage polarization. Mechanistically, Sch B regulated macrophage polarization through inhibition of the nuclear factor (NF)-κB signaling pathway via PPARγ both in vivo and in vitro.

Conclusions

These results suggested that Sch B alleviated carbon tetrachloride (CCl₄)-induced liver inflammation and fibrosis by inhibiting macrophage polarization via targeting PPARγ.

Liver Fibrosis: Therapeutic Targets and Advances in Drug Therapy

Liver fibrosis is an abnormal wound repair response caused by a variety of chronic liver injuries, which is characterized by over-deposition of diffuse extracellular matrix (ECM) and anomalous hyperplasia of connective tissue, and it may further develop into liver cirrhosis, liver failure or liver cancer. To date, chronic liver diseases accompanied with liver fibrosis have caused significant morbidity and mortality in the world with increasing tendency. Although early liver fibrosis has been reported to be reversible, the detailed mechanism of reversing liver fibrosis is still unclear and there is lack of an effective treatment for liver fibrosis. Thus, it is still a top priority for the research and development of anti-fibrosis drugs. In recent years, many strategies have emerged as crucial means to inhibit the occurrence and development of liver fibrosis including anti-inflammation and liver protection, inhibition of hepatic stellate cells (HSCs) activation and proliferation, reduction of ECM overproduction and acceleration of ECM degradation. Moreover, gene therapy has been proved to be a promising anti-fibrosis method. Here, we provide an overview of the relevant targets and drugs under development. We aim to classify and summarize their potential roles in treatment of liver fibrosis, and discuss the challenges and development of anti-fibrosis drugs.

The ameliorative effect of niclosamide on bile duct ligation induced liver fibrosis via suppression of NOTCH and Wnt pathways

Liver fibrosis is the conjoint consequence of almost all chronic liver diseases. Cholestatic liver injury is a significant stimulus for fibrotic liver. This study was conducted to investigate the hepatoprotective effect of niclosamide as a NOTCH inhibitor and on the Wnt pathway against cholestatic liver fibrosis (CLF) which was experimentally induced by bile duct ligation (BDL). Rats were randomly divided into five main groups (6 per group): sham, BDL, BDL/niclosamide 5, BDL/niclosamide 10 and niclosamide 10 only group. Niclosamide was administered intraperitoneally (i.p.) for 4 weeks starting at the same day of surgery at doses 5 and 10 mg/kg. Liver function, cholestasis, oxidative stress, inflammation, liver fibrosis, NOTCH signaling pathway and Wnt pathway markers were assessed. Niclosamide (5 and 10 mg/kg) significantly reduced liver enzymes levels, oxidative stress, inflammation and phosphorylated signal transducer and activator of transcription3 (p-STAT3). Niclosamide (5 and 10 mg/kg) also significantly reduced NOTCH pathway (Jagged1, NOTCH2, NOTCH3, HES1, SOX9), Wnt pathway (Wnt5B, and Wnt10A), and fibrosis (transforming growth factor-beta1 (TGF-β1), alpha smooth muscle actin (α-SMA) and collagen deposition with more prominent effect of the higher dose 10 mg/kg. So, this study presents nicloamide as a promising antifibrotic agent in CLF through inhibition of NOTCH and Wnt pathways.

PPARs as Metabolic Sensors and Therapeutic Targets in Liver Diseases

Carbohydrates and lipids are two components of the diet that provide the necessary energy to carry out various physiological processes to help maintain homeostasis in the body. However, when the metabolism of both biomolecules is altered, development of various liver diseases takes place; such as metabolic-associated fatty liver diseases (MAFLD), hepatitis B and C virus infections, alcoholic liver disease (ALD), and in more severe cases, hepatocelular carcinoma (HCC). On the other hand, PPARs are a family of ligand-dependent transcription factors with an important role in the regulation of metabolic processes to hepatic level as well as in other organs. After interaction with specific ligands, PPARs are translocated to the nucleus, undergoing structural changes to regulate gene transcription involved in lipid metabolism, adipogenesis, inflammation and metabolic homeostasis. This review aims to provide updated data about PPARs’ critical role in liver metabolic regulation, and their involvement triggering the genesis of several liver diseases. Information is provided about their molecular characteristics, cell signal pathways, and the main pharmacological therapies that modulate their function, currently engaged in the clinic scenario, or in pharmacological development.

The Agonists of Peroxisome Proliferator-Activated Receptor-γ for Liver Fibrosis

Liver fibrosis is a common link in the transformation of acute and chronic liver diseases to cirrhosis. It is of great clinical significance to study the factors associated with the induction of liver fibrosis and elucidate the method of reversal. Peroxisome proliferator-activated receptors (PPARs) are a class of nuclear transcription factors that can be activated by peroxisome proliferators. PPARs play an important role in fibrosis of various organs, especially the liver, by regulating downstream targeted pathways, such as TGF-β, MAPKs, and NF-κB p65. In recent years, the development and screening of PPAR-γ ligands have become a focus of research. The PPAR-γ ligands include synthetic hypolipidemic and antidiabetic drugs. In addition, microRNAs, lncRNAs, circRNAs and nano new drugs have attracted research interest. In this paper, the research progress of PPAR-γ in the pathogenesis and treatment of liver fibrosis was discussed based on the relevant literature in recent years.

Elucidating the Mechanisms of Hugan Buzure Granule in the Treatment of Liver Fibrosis via Network Pharmacology

Objective. To holistically explore the latent active ingredients, targets, and related mechanisms of Hugan buzure granule (HBG) in the treatment of liver fibrosis (LF) via network pharmacology. Methods. First, we collected the ingredients of HBG by referring the TCMSP server and literature and filtered the active ingredients though the criteria of oral bioavailability ≥30% and drug-likeness index ≥0.18. Second, herb-associated targets were predicted and screened based on the BATMAN-TCM and SwissTargetPrediction platforms. Candidate targets related to LF were collected from the GeneCards and OMIM databases. Furthermore, the overlapping target genes were used to construct the protein-protein interaction network and “drug-compound-target-disease” network. Third, GO and KEGG pathway analyses were carried out to illustrate the latent mechanisms of HBG in the treatment of LF. Finally, the combining activities of hub targets with active ingredients were further verified based on software AutoDock Vina. Results. A total of 25 active ingredients and 115 overlapping target genes of HBG and LF were collected. Besides, GO enrichment analysis exhibited that the overlapping target genes were involved in DNA-binding transcription activator activity, RNA polymerase II-specific, and oxidoreductase activity. Simultaneously, the key molecular mechanisms of HBG against LF were mainly involved in PI3K-AKT, MAPK, HIF-1, and NF-κB signaling pathways. Also, molecular docking simulation demonstrated that the key targets of HBG for antiliver fibrosis were IL6, CASP3, EGFR, VEGF, and MAPK. Conclusion. This work validated and predicted the underlying mechanisms of multicomponent and multitarget about HBG in treating LF and provided a scientific foundation for further research.

Classifying the Linkage between Adipose Tissue Inflammation and Tumor Growth through Cancer-Associated Adipocytes

Recently, tumor microenvironment (TME) and its stromal constituents have provided profound insights into understanding alterations in tumor behavior. After each identification regarding the unique roles of TME compartments, non-malignant stromal cells are found to provide a sufficient tumorigenic niche for cancer cells. Of these TME constituents, adipocytes represent a dynamic population mediating endocrine effects to facilitate the crosstalk between cancer cells and distant organs, as well as the interplay with nearby tumor cells. To date, the prevalence of obesity has emphasized the significance of metabolic homeostasis along with adipose tissue (AT) inflammation, cancer incidence, and multiple pathological disorders. In this review, we summarized distinct characteristics of hypertrophic adipocytes and cancer to highlight the importance of an individual's metabolic health during cancer therapy. As AT undergoes inflammatory alterations inducing tissue remodeling, immune cell infiltration, and vascularization, these features directly influence the TME by favoring tumor progression. A comparison between inflammatory AT and progressing cancer could potentially provide crucial insights into delineating the complex communication network between uncontrolled hyperplastic tumors and their microenvironmental components. In turn, the comparison will unravel the underlying properties of dynamic tumor behavior, advocating possible therapeutic targets within TME constituents.

Inflammasome/NF-κB translocation inhibition via PPARγ agonist mitigates inorganic mercury induced nephrotoxicity

Mercury (Hg) pollution poses global human health and environmental risks. However, still knowledge gaps exist on both exposures and health effects. Here, we combined transcriptome sequencing technique to further investigate the specific mechanisms of inorganic Hg toxicity in the kidney. Strikingly, transcriptomic analysis revealed that 4174 unigenes (including 2646 upregulated and 1528 downregulated unigenes) were differentially expressed under acute HgCl₂ (5 mg/kg) exposure in the kidney. Additionally, we observed that HgCl₂ selectively induced tumor necrosis factor superfamily (TNFSF) to participate in renal damage, which was consistent with the high-throughput sequencing data. The phenomenon is accompanied by NLRP3 inflammasome and NF-κB signal activation in the kidney. Simultaneously, ELISA results shown that TNF-α, IL-1β and IL-6 concentrations in the kidney were significant increased. KEGG enrichment analysis showed that peroxisome proliferators-activated receptors (PPAR) signaling pathway might be vital toxic mechanism of Hg in the kidney. Then, our data showed that PPARγ agonist (GW 1929) attenuated HgCl₂ (15 μg/ml)-induced apoptosis and NLRP3 inflammasome activation via decreasing translocation of NF-κB and increasing Bcl2 levels in vitro. Along with this, we demonstrated that PPARγ antagonists (GW9662) effectively aggravated HgCl₂-induced nephrotoxicity. Overall, our results suggested that PPARγ signaling pathway is considered to be a protective mechanism to combat against HgCl₂-triggered NLRP3 inflammasome activation and apoptosis.

Peroxisome Proliferator-Activated Receptors and Their Novel Ligands as Candidates for the Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a major health issue worldwide, frequently associated with obesity and type 2 diabetes. Steatosis is the initial stage of the disease, which is characterized by lipid accumulation in hepatocytes, which can progress to non-alcoholic steatohepatitis (NASH) with inflammation and various levels of fibrosis that further increase the risk of developing cirrhosis and hepatocellular carcinoma. The pathogenesis of NAFLD is influenced by interactions between genetic and environmental factors and involves several biological processes in multiple organs. No effective therapy is currently available for the treatment of NAFLD. Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that regulate many functions that are disturbed in NAFLD, including glucose and lipid metabolism, as well as inflammation. Thus, they represent relevant clinical targets for NAFLD. In this review, we describe the determinants and mechanisms underlying the pathogenesis of NAFLD, its progression and complications, as well as the current therapeutic strategies that are employed. We also focus on the complementary and distinct roles of PPAR isotypes in many biological processes and on the effects of first-generation PPAR agonists. Finally, we review novel and safe PPAR agonists with improved efficacy and their potential use in the treatment of NAFLD.

Crocin attenuates CCl4-induced liver fibrosis via PPAR-γ mediated modulation of inflammation and fibrogenesis in rats

BACKGROUND

Liver fibrosis is a chronic pathological condition with a leading cause of liver-related mortality worldwide. In the present study, we have evaluated the antifibrotic effect of crocin, a carotenoid present in the stigma of Crocus sativus, and also explored its putative mechanism of action.

METHODS

Liver fibrosis was induced by intraperitoneal administration of 30% carbon tetrachloride (CCl₄). The crocin was administered orally at 20, 40 and 80 mg/kg body weight along with CCl₄ up to 8 weeks.

RESULTS

Chronic exposure to CCl₄ resulted in elevated levels of liver enzymes and reduced cytochrome P450 2E1 (CYP2E1) activity in the liver. The liver tissue showed cellular swelling, vacuolization, necrosis, infiltration of inflammatory cells and fibrotic changes. The crocin treatment significantly lowered the levels of liver enzymes in serum and improved the liver CYP2E1 mRNA levels. The pathological changes in the liver were also lowered by crocin treatment. The level of pro-inflammatory cytokines, nuclear factor-kappa B, interleukin-6 and tumor necrosis factor α and fibrogenic factor, transforming growth factor β, and α-smooth muscle actin were elevated by the CCl₄ in the liver tissue. However, crocin treatment at different doses significantly reduced the expression of these factors. The increased caspase 3/7 activity was also lowered by crocin. CCl₄ administration decreased the expression of peroxisome proliferator-activated receptor γ (PPAR-γ) in liver tissue. The improved PPAR-γ expression in the liver by crocin treatment indicates its role in the therapeutic effect of crocin.

CONCLUSIONS

Crocin attenuated the various events in the progression of liver fibrosis via PPAR-γ mediated modulation of inflammatory and fibrogenic pathways.

PPARs as Metabolic Regulators in the Liver: Lessons from Liver-Specific PPAR-Null Mice

Peroxisome proliferator-activated receptor (PPAR) α, β/δ, and γ modulate lipid homeostasis. PPARα regulates lipid metabolism in the liver, the organ that largely controls whole-body nutrient/energy homeostasis, and its abnormalities may lead to hepatic steatosis, steatohepatitis, steatofibrosis, and liver cancer. PPARβ/δ promotes fatty acid β-oxidation largely in extrahepatic organs, and PPARγ stores triacylglycerol in adipocytes. Investigations using liver-specific PPAR-disrupted mice have revealed major but distinct contributions of the three PPARs in the liver. This review summarizes the findings of liver-specific PPAR-null mice and discusses the role of PPARs in the liver.