Pathogenesis of liver fibrosis

Optimization of culture conditions to generate vascularized multi-lineage liver organoids with structural complexity and functionality

Hepatic organoids (HOs), primarily composed of hepatobiliary cells, do not represent the pathogenesis of liver diseases due to the lack of non-parenchymal cells. Multi-lineage liver organoids (mLOs) containing various cell types found in the liver offer a promising in vitro disease model. However, their structural complexity remains challenging to achieve due to the difficulty in optimizing culture conditions that meet the growth need of all component cell types. Here, we demonstrate that cystic HOs generated from hPSCs can be expanded long-term and serve as a continuous source for generating complex mLOs. Assembling cystic HOs with hPSC-derived endothelial and hepatic stellate cell-like cells under conventional HO culture conditions failed to support the development of multiple cell types within mLOs, resulting in biased differentiation towards specific cell types. In contrast, modulating the cAMP/Wnt/Hippo signaling pathways with small molecules during assembly and differentiation phases efficiently generate mLOs containing both hepatic parenchymal and non-parenchymal cells. These mLOs exhibited structural complexity and functional maturity, including vascular network formation between parenchymal lobular structures, cell polarity for bile secretion, and the capacity to respond to fibrotic stimuli. Our study underscores the importance of modulating signaling pathways to enhance mLO structural complexity for applications in modeling liver pathologies.

Quantitative pharmacodynamics functional evaluation of Chinese medicine Qizhu formula in mice with dynamic near-infrared photoacoustic imaging

Background & Aims

Effective anti-fibrotic drugs and new non-invasive evaluation methods for liver fibrosis (LF) are urgently needed. Our study aimed to evaluate the histological effects of the Qizhu (QZ) formula on LF and to explore a non-invasive Near-infrared photoacoustic imaging (NIR-PAI) kinetic model for liver function detection and pharmacodynamic evaluation.

Methods

C57BL/6 J mice were randomly divided into six groups (n=6). An LF model was induced by CCl4 for 8 weeks, followed by an 8-week treatment period. Histological and serological parameters were assessed, and indocyanine green (ICG) metabolism (maximum peak time [Tmax] and half-life [T1/2]) was monitored by NIR-PAI. Spearman correlation analysis was conducted to evaluate correlations.

Results & Conclusions

Histological and serological results confirmed the anti-fibrotic effects of QZ. NIR-PAI kinetic parameters indicated that QZ shortened the Tmax and T1/2 of ICG. There were good correlations between ICG metabolism and liver histopathology. The non-invasive NIR-PAI kinetic model shows potential in liver function detection and pharmacodynamic evaluation.

Advances in liver organoids: replicating hepatic complexity for toxicity assessment and disease modeling

The lack of in vivo accurate human liver models hinders the investigation of liver-related diseases, injuries, and drug-related toxicity, posing challenges for both basic research and clinical applications. Traditional cellular and animal models, while widely used, have significant limitations in replicating the liver's complex responses to various stressors. Liver organoids derived from human pluripotent stem cells, adult stem cells primary cells, or tissues can mimic diverse liver cell types, major physiological functions, and architectural features. Recent advancements in the field have shown that some liver organoids have sufficient accuracy to replicate specific aspects of the human liver's complexity. This review highlights recent progress in liver organoid research, with a particular emphasis on their potential for toxicity assessment and disease modeling. The intrinsic advantages of liver organoids include higher sensitivity and suitability for long-term studies, which enhance the predictive value in drug and nanomaterial toxicity testing. The integration of liver organoids with microfluidic devices enables the simulation of the liver microenvironment and facilitates high-throughput drug screening. The liver organoids also serve as ideal platforms for studying liver diseases such as hepatitis, liver fibrosis, viral liver diseases, and monogenic diseases. Additionally, this review discusses the advantages and limitations of liver organoids along with potential avenues for future research.

The interactive role of microRNA and other non-coding RNA in hepatitis B (HBV) associated fibrogenesis

One of the outstanding features of chronic hepatitis B infection (CHB) is its strong association with liver fibrosis. CHB induced inflammation and injury trigger multiple biochemical and physical changes that include the promotion of a wide range of cytokines, chemokines and growth factors that activate hepatic stellate cells (HSCs) CHB induced activation of hepatic stellate cells (HSCs) is regarded as a central event in fibrogenesis to directly promote the synthesis of myofibroblasts and the expression of a range of materials to repair injured liver tissue. Fibrogenesis is modulated by the mainstream epigenetic machinery, as well as by non-coding RNA (ncRNA) that are often referred to as an ancillary epigenetic response to fine tune gene expression. Although extensive research has explained the regulatory role of ncRNA in liver fibrogenesis, most of this research relates to non-CHB etiologies. This review paper outlines the complex interactive regulatory role of microRNA (miRNA) and their interaction with long non-coding RNA (lncRNA), circular RNA (circRNA) and the mainstream epigenetic machinery in CHB induced liver fibrosis. The paper also illustrates some of the difficulties involved in translating candidate ncRNA into approved drugs or diagnostic tools. In conclusion, the important regulatory role of ncRNA in CHB induced liver fibrosis warrants further investigation to exploit their undoubted potential as diagnostic and therapeutic agents.

Peptidoglycan isolated from the fruit of Lycium barbarum alleviates liver fibrosis in mice by regulating the TGF-β/Smad7 signaling and gut microbiota

The hepatoprotective effect of the fruit of Lycium barbarum has been documented in China over millennia. Lycium barbarum polysaccharides (LBPs) were the first macromolecules reported to mitigate liver fibrosis in carbon tetrachloride (CCl4)-treated mice. Herein, a neutral peptidoglycan, named as LBPW, was extracted from the fruit of Lycium barbarum. In this study, we investigated the hepatoprotective mechanisms of LBPW. CCl4-induced liver fibrosis mice were administered LBPW (50, 100, 200 mg ·kg-1 ·d-1, i.p.) or (100, 200, 300 mg· kg-1 ·d-1, i.g.) for 6 weeks. We showed that either i.p. or i.g. administration of LBPW dose-dependently attenuated liver damage and fibrosis in CCl4-treated mice. Pharmacokinetic analysis showed that cyanine 5.5 amine (Cy5.5)-labeled LBPW (Cy5.5-LBPW) could be detected in the liver through i.p. and i.g. administration with i.g.-administered Cy5.5-LBPW mainly accumulating in the intestine. In TGF-β1-stimulated LX-2 cells as well as in the liver of CCl4-treated mice, we demonstrated that LBPW significantly upregulated Smad7, a negative regulator of TGF-β/Smad signaling, to retard the activation of hepatic stellate cells (HSCs) and prevent liver fibrosis. On the other hand, LBPW significantly boosted the abundance of Akkermansia muciniphila (A. muciniphila) and fortified gut barrier function. We demonstrated that A. muciniphila might be responsible for the efficacy of LBPW since decreasing the abundance of this bacterium by antibiotics (Abs) blocked the effectiveness of LBPW. Overall, our results show that LBPW may exert the hepatoprotective effect via rebalancing TGF-β/Smad7 signaling and propagating gut commensal A. muciniphila, suggesting that LBPW could be leading components to be developed as new drug candidates or nutraceuticals against liver fibrosis.

Design and Synthesis of Dual Galectin-3 and EGFR Inhibitors Against Liver Fibrosis

Liver fibrosis, mainly arising from chronic viral or metabolic liver diseases, is a significant global health concern. There is currently only one FDA-approved drug (Resmetirom) in the market to combat liver fibrosis. Both galectin-3 and epidermal growth factor receptor (EGFR) play important roles in liver fibrosis, while galectin-3 may interact with EGFR. Galectin-3 inhibitors, typically lactose or galactose derivatives may inhibit liver fibrosis. We hypothesized that targeting both galectin-3 and EGFR may have better effect against liver fibrosis. Here, EGFR inhibitor erlotinib was used in a series of designed galectin-3 inhibitors after hybridization with the pharmacophore structure in reported galectin-3 inhibitors to impede hepatic stellate cells (HSCs) activation by a typical method of click chemistry. Bioactivity test results showed that compound 29 suppressed TGF-β-induced upregulation of fibrotic markers (α-SMA, fibronectin-1, and collagen I). The preferred compound 29 displayed better binding to galectin-3 (KD=52.29 μM) and EGFR protein (KD=3.31 μM) by SPR assay. Further docking studies were performed to clarify the possible binding mode of compound 29 with galectin-3 and EGFR. Taken together, these results suggested that compound 29 could be a potential dual galectin-3 and EGFR inhibitor as leading compound for anti-liver fibrosis new drug development.

A novel pectin-like polysaccharide from Crocus sativus targets Galectin-3 to inhibit hepatic stellate cells activation and liver fibrosis

Liver fibrosis may lead to cirrhosis and even cancer without effective clinical medicine available. Previous studies demonstrated that galactan-containing pectins or pectin-like polysaccharides might target Galectin-3 (Gal-3) to impede fibrosis. This research aims to discover novel pectin-like galactan to interfere with fibrosis for potential new drug development. Thus, we purify a novel homogeneous Rhamnogalacturonan-I like polysaccharide with galactan input, XHH2, from the Crocus sativus flower. XHH2 (MW: 35.7 kDa) consists of rhamnose, galacturonic acid, galactose, and arabinose in ratios of 6.6: 6.1: 25.2: 12.1. The backbone of XHH2 comprises 1, 3, 6-Gal and 1, 3, 4-GalA, with branches at O-3 of 1, 3, 6-Gal and O-4 of 1, 3, 4-GalA. O-3 branches include 1, 3-Gal, 1, 4-Gal, 1, 6-Gal, T-Gal, and T-Glc, while O-4 branches consist of 1, 2, 4-Rha, 1, 4-GalA, 1, 5-Ara, T-Ara, T-Gal, and T-α-HexA. Surface plasmon resonance measurement shows that XHH2 binds to both Gal-3 and integrin β1 to block Gal-3/integrin β1 interaction. Mechanism studies further suggest that XHH2 inactivates hepatic stellate cells (HSCs) via disturbing the Gal-3/Integrin-β1/FAK pathway to alleviate liver injury and fibrosis in vitro & in vivo. XHH2 shows a favorable drug safety in the acute toxicity test of oral administration of XHH2 in mice. Overall, XHH2 is an active ingredient against liver fibrosis by targeting the interaction between Gal-3 and Integrin-β1.

Ether bond-modified lipid nanoparticles for enhancing the treatment effect of hepatic fibrosis

Lipid nanoparticle (LNP)-mediated RNA delivery holds significant potential for the treatment of various liver diseases. Ionizable lipids play a crucial role in the formulation of LNPs and directly influence their delivery efficiency. In this study, we introduced an innovative concept by incorporating an ether bond into the hydrophobic tail of ionizable lipids for the first time. Three ionizable lipids, namely, ND-O1, ND-O2, and ND-O3, were synthesized based on 1-octylnonyl 8-[(2-hydroxyethyl)-[8-(nonyloxy)-8-oxooctyl] amino] octanoate (Lipid M). The efficacy of lipids-based LNPs for the delivery of the heat shock protein 47 (HSP47)-targeted siRNA to the liver was investigated. Compared to Lipid M-based LNP (LNP-M), it was observed that ND-O1 based LNP (LNP-O1) exhibited enhanced siRNA transfection efficiency in activated fibroblasts. In the fibrosis mice, LNP-O1 effectively suppressed HSP47 expression by approximately 84%, which was three times more effective than LNP-M, resulting in a significant decrease of collagen deposition and an amelioration of liver fibrosis. These findings highlighted the potential application of ND-O1 as an ionizable lipid for enhancing the efficient delivery of LNPs-delivered siRNA to the liver. Furthermore, this ionizable lipid design strategy offers a promising avenue for the improvement of the LNP delivery system.

Prognostic assessment of early-stage liver cirrhosis induced by HCV using an integrated model of CX3CR1-associated immune infiltration genes

Chemokine (C-X3-C motif) Receptor 1 (CX3CR1) primarily mediates the chemotaxis and adhesion of immune cells. However, its role in hepatitis C virus (HCV)-induced early-stage liver cirrhosis remains unexplored. GSE15654 was downloaded from the GEO database. The Cox regression model, CIBERSORT, and LASSO technique were utilized to identify CX3CR1-associated immune infiltration genes (IIGs). Surgical resection samples were collected for verification, including 3 healthy controls (HC), 4 individuals with HCV-induced hepatic cirrhosis, and 3 with HCV-induced liver failure. High CX3CR1 expression correlated with worse prognosis in early-stage cirrhosis. CX3CR1-associated IIGs, namely ACTIN4, CD1E, TMCO1, and WSF1, were identified, showing specific expression in the livers of individuals with post-hepatic cirrhosis and liver failure compared to HC. LOC400499 and MTHFD2 were elevated in individuals with liver failure in comparison to those with hepatocirrhosis. Notably, high infiltration of plasma cells and low infiltration of monocytes were predictive of poor prognosis in early-stage cirrhosis. The combined risk model predicted that high expression of CX3CR1-associated IIGs and increased infiltration of plasma cells were associated with unfavorable prognosis in individuals with HCV-induced early-stage liver cirrhosis. The developed combined risk model effectively predicted the prognosis of these individuals.

Alleviation of liver fibrosis by inhibiting a non-canonical ATF4-regulated enhancer program in hepatic stellate cells

Liver fibrosis is a critical liver disease that can progress to more severe manifestations, such as cirrhosis, yet no effective targeted therapies are available. Here, we identify that ATF4, a master transcription factor in ER stress response, promotes liver fibrosis by facilitating a stress response-independent epigenetic program in hepatic stellate cells (HSCs). Unlike its canonical role in regulating UPR genes during ER stress, ATF4 activates epithelial-mesenchymal transition (EMT) gene transcription under fibrogenic conditions. HSC-specific depletion of ATF4 suppresses liver fibrosis in vivo. Mechanistically, TGFβ resets ATF4 to orchestrate a unique enhancer program for the transcriptional activation of pro-fibrotic EMT genes. Analysis of human data confirms a strong correlation between HSC ATF4 expression and liver fibrosis progression. Importantly, a small molecule inhibitor targeting ATF4 translation effectively mitigates liver fibrosis. Together, our findings identify a mechanism promoting liver fibrosis and reveal new opportunities for treating this otherwise non-targetable disease.

Pathological Microenvironment-Remodeling Nanoparticles to Alleviate Liver Fibrosis: Reversing Hepatocytes-Hepatic Stellate Cells Malignant Crosstalk

During the onset and malignant development of liver fibrosis, the pernicious interplay between damaged hepatocytes and activated hepatic stellate cells (HSCs) induce a self-perpetuating vicious cycle, deteriorating fibrosis progression and posing a grave threat to public health. The secretions released by damaged hepatocytes and activated HSCs interact through autocrine or paracrine mechanisms, involving multiple signaling pathways. This interaction creates a harsh microenvironment and weakens the therapeutic efficacy of single-cell-centric drugs. Herein, a malignant crosstalk-blocking strategy is prompted to remodel vicious cellular interplay and reverse pathological microenvironment to put an end to liver fibrosis. Collagenases modified, bardoxolone and siTGF-β co-delivered nanoparticles (C-NPs/BT) are designed to penetrate the deposited collagen barriers and further regulate the cellular interactions through upregulating anti-oxidative stress capacity and eliminating the pro-fibrogenic effects of TGF-β. The C-NPs/BT shows successful remodeling of vicious cellular crosstalk and significant disease regression in animal models. This study presents an innovative strategy to modulate cellular interactions for enhanced anti-fibrotic therapy and suggests a promising approach for treating other chronic liver diseases.

Low Dose of Nickel and Benzo [a] Anthracene in Rat-Diet, Induce Apoptosis, Fibrosis, and Initiate Carcinogenesis in Liver via NF-Ƙβ Pathway

Environmental contaminants such as polycyclic aromatic hydrocarbon (PAH) and heavy metals are major contaminants of food such as fish thus serving as source of exposure to human. This study was designed to evaluate the carcinogenic risk and other risks associated with long-term consumption of environmentally relevant dose of nickel and benzo [a] anthracene in rats. Thirty-six (36) male rats weighing between 80 and 100 g were assigned into 6 groups of 6 animals each; normal, nickel-, and benzo [a] anthracene-exposed groups for 12 and 24 weeks, respectively. Micronucleus and comet analyses were done in the blood, liver, and bone marrow. Liver function, redox, and inflammatory markers (AST, ALT, GGT, SOD, GSH, MDA, protein carbonyl, protein thiol, total protein, IL-10, 1L-1β, TNF-α, TGF-β NF-Ƙβ, and 8-oxodeoxyguansine) were analysed by standard methods. Immuno-histochemical quantification of Bax, Bcl2, and Erk 1/2 as well as mRNA expression of cyclin D1 was done in liver. From the results, weight gain was observed in varying degrees throughout the exposure period. The polychromatic erythrocytes/normochromatic erythrocytes ratio > 0.2 indicates no cytotoxic effects on the bone marrow. Percentage-MnPCE in blood significantly (p < 0.05) increased throughout exposure duration. Percentage tail DNA in blood was significantly (< 0.05) increased at weeks 20 and 24 in the exposed groups and in liver at weeks 12 (16.22 ± 0.47) and 24 (17.00 ± 0.36) of nickel-exposed rats. The aspartate amino transferase (AST):alanine amino transferase (ALT) ratio indicated fatty liver disease in the benzo [a] anthracene (0.90) and acute liver injury in the nickel (> 10 times greater than the upper limits of the reference group) exposed groups during the first 12 weeks. Observation from the histological and cytological data of the liver revealed the presence of inflammation, fibrosis, and high nuclear/cytoplasmic ratio, respectively, in the nickel and benzo [a] anthracene groups. Only benzo [a] anthracene induced liver oxidative stress with significant (p < 0.05) decrease in SOD (0.64 ± 0.02) activity and increase in protein carbonyl (7.60 ± 0.80 × 10-5) and MDA (57.10 ± 6.64) concentration after 24 weeks. Benzo [a] anthracene up-regulated the cyclin D1 expression and significantly (p < 0.05) increased the levels of the cytokines. Nickel and benzo [a] anthracene significantly (p < 0.05) increased the Bax (183.45 ± 6.50 and 199.76 ± 10.04) and Erk 1/2 (108.25 ± 6.41 and 136.74 ± 4.22) levels when compared with the control (37.43 ± 22.22 and 60.37 ± 17.86), respectively. Overall result showed that the toxic effects of nickel and benzo [a] anthracene might involve fibrosis, cirrhosis, apoptosis, and inflammation of the liver. As clearly demonstrated in this study, benzo [a] anthracene after the 24 weeks of exposure stimulates carcinogenic process by suppressing the liver antioxidant capacity, altering apoptotic, cell proliferation, and differentiation pathways.

Methyl donor ameliorates CCl4-induced liver fibrosis by inhibiting inflammation, and fibrosis through the downregulation of EGFR and DNMT-1 expression

Methyl donors regulate the one-carbon metabolism and have significant potential to reduce oxidative stress and inflammation. Therefore, this study aims to investigate the protective effect of methyl donors against CCl4-induced liver fibrosis. Liver fibrosis was induced in male Sprague Dawley rats using CCl4 at a dose of 1 ml/kg (twice a week for a 4-week, via intraperitoneal route). Subsequently, methyl donor treatments were given orally for the next six weeks while continuing CCl4 administration. After 10 weeks, biochemical, histopathology, immunohistochemistry, western blotting, and qRT-PCR were performed. Methyl donor treatment significantly ameliorated ALT, AST, ALP levels, and oxidative stress associated with CCl4-induced liver injury. The histopathological investigation also demonstrated the hepatoprotective effect of methyl donors against CCl4-induced liver fibrosis, showing reduced tissue damage, collagen deposition, and attenuating the expression of the COL1A1 gene. Further, methyl donors inhibited the CCl4-induced increase in DNMT-1 and NF-κB p65 expression with an upregulation of AMPK. Methyl donor downregulated the CCl4-induced increase in inflammatory and fibrosis related gene expression and inhibited the apoptosis with a downregulation of EGFR expression. Here, we provide the first evidence that methyl donor combinations prevent liver fibrosis by attenuating oxidative stress, inflammation, and fibrosis through DNMT-1 and EGFR downregulation.

Multi-omics and experimental analysis unveil the key components in Scutellaria baicalensis Georgi to alleviate hepatic fibrosis via regulating cPLA2-mediated arachidonic acid metabolism

BACKGROUND

Scutellaria baicalensis Georgi, a traditional Chinese herb, is known for its various biological effects, including antibacterial, anti-inflammatory, antioxidative, and antitumor properties. However, the function and mechanisms of methanol extract of Scutellaria baicalensis Georgi (MESB) in treating hepatic fibrosis remain unclear.

METHODS

This study utilized a CCl4-induced mouse model of hepatic fibrosis to assess the effects of MESB through histopathological analysis and serum tests. The anti-fibrosis mechanism of MESB was investigated using qPCR, Western blotting, RNA interference, proteomics, and metabolomics. Spatial metabolomics identified key components of MESB in liver tissue, while molecular docking determined their targets.

RESULTS

Treatment with MESB alleviated hepatic pathological changes and reversed hepatic fibrosis in the CCl4-induced models, as evidenced by decreased collagen fibers deposition, reduced expression of hepatic fibrosis markers COL1A1, FN, and PAI-1, and lowered serum levels of AST and ALT. In vitro, MESB inhibited the proliferation of LX-2 cells and the expression of hepatic fibrosis markers. Furthermore, MESB intervention modulated various pathways, particularly those involved in metabolic pathways. Subsequent metabolomics analysis demonstrated that MESB disrupted glycerophospholipid metabolism and suppressed arachidonic acid metabolism. MESB downregulated the expression of cPLA2 in LX-2 cells, leading to decreased production of arachidonic acid and its downstream inflammatory mediators. Meanwhile, MESB inhibited the expression of cPLA2 and its downstream NF-κB pathway in the liver tissues of models induced by CCl4. Additionally, silencing cPLA2 markedly reduced the expressions of COL1A1, FN, and PAI-1. Spatial metabolomics analysis confirmed the penetration of baicalein, wogonin and wogonoside into liver tissue. Further results indicated that baicalein and wogonin inhibited the expression of cPLA2, while baicalin and wogonoside do not exhibit this effect. Moreover, molecular docking suggested that baicalein and wogonin possess the potential to directly interact with cPLA2.

CONCLUSION

This study reveals that MESB is crucial in preventing hepatic fibrosis via the cPLA2-mediated arachidonic acid metabolic pathway, highlighting its key active components as potential drugs for fibrosis treatment.

PLIN5 contributes to lipophagy of hepatic stellate cells induced by inorganic arsenic

Arsenic exposure triggers the activation of hepatic stellate cells (HSCs), resulting in liver fibrosis (LF). A significant decrease in lipid droplets marks the activation of HSCs. However, the exact underlying molecular mechanism remains elusive. Lipophagy, a specialized form of selective autophagy, is crucial for the degradation of lipid droplets to maintain intracellular lipid metabolism homeostasis. In this study, arsenic treatment induced lipophagy, as evidenced by the co-localization of LC3 with lipid droplets. Remarkably, arsenic exposure increased the expression levels of Perilipin 5 (PLIN5), a lipid droplet-associated protein, both at the mRNA and protein levels. Moreover, silencing PLIN5 influenced arsenic-induced lipolysis. Consequently, the results of this study indicate that PLIN5 serves as a substrate protein involved in arsenic-induced lipophagy. This research offers a novel perspective on the mechanisms of arsenic-induced HSCs activation and liver lipid metabolism, potentially guiding new strategies for the prevention and treatment of arsenic-related liver diseases.

Live-cell imaging of human liver fibrosis using hepatic micro-organoids

Due to the limitations of available in vitro systems and animal models, we lack a detailed understanding of the pathogenetic mechanisms of and have minimal treatment options for liver fibrosis. Therefore, we engineered a live-cell imaging system that assessed fibrosis in a human multilineage hepatic organoid in a microwell (i.e., microHOs). Transcriptomic analysis revealed that TGFB converted mesenchymal cells in microHOs into myofibroblast-like cells resembling those in fibrotic human liver tissue. When pro-fibrotic intracellular signaling pathways were examined, the antifibrotic effect of receptor-specific tyrosine kinase inhibitors was limited to the fibrosis induced by the corresponding growth factor, which indicates their antifibrotic efficacy would be limited to fibrotic diseases solely mediated by that growth factor. Based upon transcriptomic and transcription factor activation analyses in microHOs, glycogen synthase kinase 3β and p38 MAPK inhibitors were identified as potential new broad-spectrum therapies for liver fibrosis. Other new therapies could subsequently be identified using the microHO system.

Humanized monoacylglycerol acyltransferase 2 mice develop metabolic dysfunction-associated steatohepatitis

Mice lacking monoacylglycerol acyltransferase 2 (mMGAT21) are resistant to diet-induced fatty liver, suggesting hMOGAT2 inhibition is a viable option for treating metabolic dysfunction-associated steatotic liver disease (MASLD)/metabolic dysfunction-associated steatohepatitis (MASH). We generated humanized hMOGAT2 mice (HuMgat2) for use in pre-clinical studies testing the efficacy of hMOGAT2 inhibitors for treating MASLD/MASH. HuMgat2 mice developed MASH when fed a steatotic diet. Computer-aided histology revealed the presence of hepatocyte cell ballooning, immune cell infiltration, and fibrosis. Hepatocytes accumulated Mallory-Denk bodies containing phosphorylated p62/sequestosome-1-ubiquitinated protein aggregates likely caused by defects in autophagy. Metainflammation and apoptotic cell death were seen in the livers of HuMgat2 mice. Treating HuMgat2 mice with elafibranor reduced several MASH phenotypes. RNASeq analysis predicted changes in bile acid transporter expression that correlated with altered bile acid metabolism indicative of cholestasis. Our results suggest that HuMgat2 mice will serve as a pre-clinical model for testing hMOGAT2 inhibitor efficacy and toxicity and allow for the study of hMOGAT2 in the context of MASH.

CCCP induces hepatic stellate cell activation and liver fibrogenesis via mitochondrial and lysosomal dysfunction

Hepatic stellate cells (HSCs) are primary cells for development and progression of liver fibrosis. Mitophagy is an essential lysosomal process for mitochondrial homeostasis, which can be activated by carbonyl cyanide m-chlorophenyl hydrazone (CCCP), a representative mitochondrial uncoupler. However, little information is available on the role of CCCP-mediated mitophagy in HSC activation and liver fibrogenesis. In this study, we showed that CCCP treatment in HSCs caused mitochondrial dysfunction proved by decreased mitochondrial membrane potential, mitochondrial DNA, and ATP contents and increased mitochondrial ROS. Moreover, CCCP induced mitophagy and impaired mitophagy flux at the later stage. This blockade of mitophagic flux effect was mediated by suppression of lysosomal activity; CCCP decreased expression of lysosomal markers and cathepsin B activity, and increased lysosomal pH. Intriguingly, CCCP treatment in LX-2 cells or primary HSCs elevated plasminogen activator inhibitor-1 (PAI-1), a typical fibrogenic marker of HSCs which was attenuated by mitochondrial division inhibitor 1, a mitophagy inhibitor. The up-regulation of PAI-1 by CCCP was not due to altered transcriptional activity but lysosomal dysfunction. In vivo acute or sub-chronic treatment of CCCP to mice induced mitophagy and fibrogenesis of liver. Hepatic fibrogenic marker (PAI-1) was incremented with mitophagy markers (parkin and PTEN-induced putative kinase 1) in the livers of CCCP injected mice. Furthermore, we found that 5-aminoimidazole-4-carboxyamide ribonucleoside reversed CCCP-mediated mitophagy and subsequent HSC activation. To conclude, CCCP facilitated HSC activation and hepatic fibrogenesis via mitochondrial dysfunction and lysosomal blockade, implying that attenuation of CCCP-related signaling molecules may contribute to treat liver fibrosis.

Guizhi Fuling Wan attenuates tetrachloromethane-induced hepatic fibrosis in rats via PTEN/AKT/mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Treatment options for hepatic fibrosis, a prevalent liver condition closely linked to cirrhosis, are currently limited. While Guizhi Fuling Wan (GFW), a pill derived from traditional Chinese herbs, has been reported to possess hepatoprotective properties, its therapeutic effect and mechanism in hepatic fibrosis remain elusive.

AIM OF THE STUDY

This study aimed to evaluate the anti-fibrotic impact of GFW and its underlying mechanisms in both in vivo and in vitro settings.

MATERIALS AND METHODS

Tetrachloromethane (CCl4) was used to induce hepatic fibrosis in male rats. In vitro, activation of hepatic stellate cells (HSCs) was triggered by platelet-derived growth factor-BB (PDGF-BB). In vivo, liver function, pathological alterations, and HSC activation were evaluated. Additionally, the impact of GFW on the activated phenotypes of Lieming Xu-2 (LX-2) cells was examined in vitro. Network pharmacology was employed to identify the potential targets of GFW in hepatic fibrosis. Lastly, the impact of GFW on the PTEN/AKT/mTOR pathway and PTEN ubiquitination in HSCs was investigated.

RESULTS

GFW alleviated CCl4-induced liver damage and scarring in rats in a dose-dependent manner and suppressed HSC activation in vivo. Moreover, GFW inhibited the proliferation, migration, differentiation, and extracellular matrix (ECM) production of activated HSCs in vitro. GFW also promoted autophagy and apoptosis of HSCs. Meanwhile, network pharmacology and in vitro studies suggested that GFW inhibits the AKT/mTOR pathway by preventing PTEN degradation by suppressing ubiquitination.

CONCLUSION

GFW attenuates Ccl4-induced hepatic fibrosis in male rats by regulating the PTEN/AKT/mTOR signaling pathway, positioning it as a potential candidate for the treatment of hepatic fibrosis.

Exploring the Updated Roles of Ferroptosis in Liver Diseases: Mechanisms, Regulators, and Therapeutic Implications

Ferroptosis, a newly discovered mode of cell death, is a type of iron-dependent regulated cell death characterized by intracellular excessive lipid peroxidation and imbalanced redox. As the liver is susceptible to oxidative damage and the abnormal iron accumulation is a major feature of most liver diseases, studies on ferroptosis in the field of liver diseases are of great interest. Studies show that targeting the key regulators of ferroptosis can effectively alleviate or even reverse the deterioration process of liver diseases. System Xc- and glutathione peroxidase 4 are the main defense regulators of ferroptosis, while acyl-CoA synthetase long chain family member 4 is a key enzyme causing peroxidation in ferroptosis. Generally speaking, ferroptosis should be suppressed in alcoholic liver disease, non-alcoholic fatty liver disease, and drug-induced liver injury, while it should be induced in liver fibrosis and hepatocellular carcinoma. In this review, we summarize the main regulators involved in ferroptosis and then the mechanisms of ferroptosis in different liver diseases. Treatment options of drugs targeting ferroptosis are further concluded. Determining different triggers of ferroptosis can clarify the mechanism of ferroptosis occurs at both physiological and pathological levels.

Understanding the complex macrophage landscape in MASLD

Metabolic dysfunction-associated steatotic liver disease (MASLD) represents a spectrum of disease states ranging from simple steatosis to metabolic dysfunction-associated steatohepatitis (MASH), which can eventually lead to the development of cirrhosis and hepatocellular carcinoma. Macrophages have long been implicated in driving the progression from steatosis to end-stage disease, yet we still know relatively little about the precise involvement of these cells in MASLD progression and/or regression. Rather, there are a considerable number of conflicting reports regarding the precise roles of these cells. This confusion stems from the fact that, until recently, macrophages in the liver were considered a homogenous population. However, thanks to recent technological advances including multi-parameter flow cytometry, single-cell RNA sequencing and spatial proteogenomics, we now know that this is not the case. Rather hepatic macrophages, even in the healthy liver, are heterogenous, existing in multiple subsets with distinct transcriptional profiles and hence likely functions. This heterogeneity is even more prominent in MASLD, where the macrophage pool consists of multiple different subsets of resident and recruited cells. To probe the unique functions of these cells and determine if targeting macrophages may be a viable therapeutic strategy in MASLD, we first need to unravel this complexity and decipher which populations and/or activation states are present and what functions each of these may play in driving MASLD progression. In this review, we summarise recent advances in the field, highlighting what is currently known about the hepatic macrophage landscape in MASLD and the questions that remain to be tackled.

Azoospermia and multi-organ damage in juvenile rats exposed to α-Terpineol from weaning to sexual maturity

This study aimed to evaluate the repeated oral administration of α-terpineol in juvenile Wistar rats over a 70-day period. The objective was to assess the potential systemic and reproductive toxicity of α-terpineol when administered by gavage at doses of 75, 150, and 300 mg/kg/day to juvenile Wistar rats for 70 days from postnatal day 24. The control group received corn oil for 70 days. During the study, various parameters were evaluated, including clinical signs, body weight, food intake, neurobehavioral observations, haematology, serum biochemistry, organ weights, steroidogenic gene expression, and histopathological examination. No toxicity-related changes were observed in body weight, food intake, neurobehavioral observations, or steroidogenic gene expression. However, sperm evaluation revealed a complete absence of sperm and delayed sexual maturation. Total cholesterol was significantly elevated in both sexes, and serum testosterone was reduced at the 150 and 300 mg/kg doses. Microscopic examination showed severe pathological changes in the testes, epididymis, liver, and kidneys of both males and females. After the 14-day recovery period, total cholesterol levels returned to the normal range, but no recovery was observed in the other organs. The no-observed-adverse-effect level was 75 mg/kg/day for male rats based on the histopathological findings in the testes, liver, and kidneys, and for female rats based on the kidney and liver histopathology.

MRI Dixon Fat-Corrected Look-Locker T1 Mapping for Quantification of Liver Fibrosis and Inflammation-A Comparison With the Non-Fat-Corrected Shortened Modified Look-Locker Inversion Recovery Technique

OBJECTIVES

This study evaluates the impact of liver steatosis on the discriminative ability for liver fibrosis and inflammation using a novel Dixon water-only fat-corrected Look-Locker T1 mapping sequence, compared with a standard shortened Modified Look-Locker Inversion Recovery (shMOLLI) sequence, with the aim of overcoming the limitation of steatosis-related confounding in liver T1 mapping.

MATERIALS AND METHODS

3 T magnetic resonance imaging of the liver including the 2 T1 mapping sequences and proton density fat fraction (PDFF) was prospectively performed in 24 healthy volunteers and 38 patients with histologically proven liver fibrosis evaluated within 90 days of liver biopsy. Paired Mann-Whitney test compared sequences between participants with and without significant liver steatosis (PDFF cutoff 10%), and unpaired Kruskal-Wallis test compared healthy volunteers to patients with early (F0-2) and advanced (F3-4) liver fibrosis, as well as low (A0-1) and marked (A2-3) inflammatory activity. Univariate and multivariate logistic regression models assessed the impact of liver steatosis on both sequences.

RESULTS

Dixon_W T1 was higher than shMOLLI T1 in participants without steatosis (median 896 ms vs 890 ms, P = 0.04), but lower in participants with liver steatosis (median 891 ms vs 973 ms, P < 0.001). Both methods accurately differentiated between volunteers and patients with early and advanced fibrosis (Dixon_W 849 ms, 910 ms, 947 ms, P = 0.011; shMOLLI 836 ms, 918 ms, 978 ms, P < 0.001), and those with mild and marked inflammation (Dixon_W 849 ms, 896 ms, 941 ms, P < 0.01; shMOLLI 836 ms, 885 ms, 978 ms, P < 0.001). Univariate logistic regression showed slightly lower performance of the Dixon_W sequence in differentiating fibrosis (0.69 vs 0.73, P < 0.01), compensated by adding liver PDFF in the multivariate model (0.77 vs 0.75, P < 0.01).

CONCLUSIONS

Dixon water-only fat-corrected Look-Locker T1 mapping accurately identifies liver fibrosis and inflammation, with less dependency on liver steatosis than the widely adopted shMOLLI T1 mapping technique, which may improve its predictive value for these conditions.

Correlation Between Real-Time Shear Wave Elastography and Liver Serum Markers in Determining the Stage of Liver Fibrosis in Patients with Chronic Liver Diseases

Introduction: Non-invasive methods aim to predict the stage of liver fibrosis in line with histological findings via biopsy. Shear wave elastography and serum markers are proven as accurate non-invasive methods for determining liver fibrosis as a modern non-invasive methods compared to liver biopsy in staging hepatic fibrosis. Aims: This study aims to determine the correlation between Shear Wave Elastography and indirect and direct serum markers of fibrosis when staging liver fibrosis. Material and methods: The study was conducted in the Clinic of Gastroenterohepatology, the Institute of Immunology and Human Genetics, and the Institute of Pathology between 2021 and 2023. The study comprises 70 patients with liver lesions, diagnosed based on clinical results, laboratory tests, and ultra-sound imaging. All patients underwent liver biopsy, classified according to Ishak and Metavir score as a reference method for diagnosing liver fibrosis. Real-time shear wave elastography was also performed as a non-invasive method and serum markers were checked for liver fibrosis. Findings: The statistical analysis indicated a positive correlation between the values of direct and indirect liver fibrosis markers and Shear Wave Elastography results. Conclusion: Our study has demonstrated that shear wave elastography has a significant positive correlation with biochemical markers of liver lesions and serum markers of liver fibrosis, whereas it has a negative correlation with platelets.

In-Depth Proteomic Analysis Reveals Phenotypic Diversity of Macrophages in Liver Fibrosis

Macrophages make up a heterogeneous population of immune cells that exhibit diverse phenotypes and functions in health and disease. Although macrophage epigenomic and transcriptomic profiles have been reported, the proteomes of distinct macrophage populations under various pathological conditions remain largely elusive. Here, we employed a label-free proteomic approach to characterize the diversity of the hepatic macrophage pool in an experimental model of CCl4-induced liver fibrosis. We found a decrease in the proportion of liver resident embryo-derived KCs (EmKCs), and a drastic increase in the proportion of monocyte-derived KCs (MoKCs) and CLEC2-Macs. Proteomic profiling revealed that MoKCs largely resembled EmKCs, whereas CLEC2-Macs exhibited greater proteomic alternations compared with EmKCs, suggesting two distinct destinations for monocyte differentiation during liver fibrosis. Furthermore, CLEC2-Macs were characterized by increased expression of proteins associated with inflammatory response, antigen processing and presentation processes, which may be involved in the pathogenesis of liver fibrosis. Collectively, our study provides insights into the considerable heterogeneity within the hepatic macrophage pool during liver fibrosis.

Computed Tomography-Derived Extracellular Volume Fraction and Splenic Size for Liver Fibrosis Staging

OBJECTIVE

Extracellular volume fraction (fECV) and liver and spleen size have been correlated with liver fibrosis stages and cirrhosis. The purpose of the current study was to determine the predictive value of fECV alone and in conjunction with measurement of liver and spleen size for severity of liver fibrosis.

METHODS

This was a retrospective study of 95 subjects (65 with liver biopsy and 30 controls). Spearman rank correlation coefficient was used to assess correlation between radiological markers and fibrosis stage. Receiver operating characteristic analysis was performed to assess the discriminative ability of radiological markers for significant (F2+) and advanced (F3+) fibrosis and cirrhosis (F4), by reporting the area under the curve (AUC).

RESULTS

The cohort had a mean age of 51.4 ± 14.4 years, and 52 were female (55%). There were 36, 5, 6, 9, and 39 in fibrosis stages F0, F1, F2, F3, and F4, respectively. Spleen volume alone showed the highest correlation ( r = 0.552, P < 0.001) and AUCs of 0.823, 0.807, and 0.785 for identification of significant and advanced fibrosis and cirrhosis, respectively. Adding fECV to spleen length improved AUCs (0.764, 0.745, and 0.717 to 0.812, 0.781, and 0.738, respectively) compared with splenic length alone. However, adding fECV to spleen volume did not improve the AUCs for significant or advanced fibrosis or cirrhosis.

CONCLUSIONS

Spleen size (measured in length or volume) showed better correlation with liver fibrosis stages compared with fECV. The combination of fECV and spleen length had higher accuracy compared with fECV alone or spleen length alone.

Highly Selective Artificial K+ Transporters Reverse Liver Fibrosis In Vivo

Liver fibrosis is a life-threatening disease that currently lacks clinically effective therapeutic agents. Given the close correlation between dysregulated intracellular K+ homeostasis and the progression of liver fibrosis, developing artificial K+ transporters mimicking the essential function of their natural counterparts in regulating intracellular K+ levels might offer an appealing yet unexplored treatment strategy. Here, we present an unconventional class of artificial K+ transporters involving the "motional" collaboration between two K+ transporter molecules. In particular, 6C6 exhibits an impressive EC50 value of 0.28 μM (i.e., 0.28 mol % relative to lipid) toward K+ and an exceptionally high K+/Na+ selectivity of 15.5, representing one of the most selective artificial K+ transporters reported to date. Most importantly, our study demonstrates, for the first time, the potential therapeutic effect of K+-selective artificial ion transporters in reversing liver fibrosis both in vitro and in vivo.

Metagenome-based characterization of the gut bacteriome, mycobiome, and virome in patients with chronic hepatitis B-related liver fibrosis

Introduction

The gut microbiota is believed to be directly involved in the etiology and development of chronic liver diseases. However, the holistic characterization of the gut bacteriome, mycobiome, and virome in patients with chronic hepatitis B-related liver fibrosis (CHB-LF) remains unclear.

Methods

In this study, we analyzed the multi-kingdom gut microbiome (i.e., bacteriome, mycobiome, and virome) of 25 CHB-LF patients and 28 healthy individuals through whole-metagenome shotgun sequencing of their stool samples.

Results

We found that the gut bacteriome, mycobiome, and virome of CHB-LF patients were fundamentally altered, characterized by a panel of 110 differentially abundant bacterial species, 16 differential fungal species, and 90 differential viruses. The representative CHB-LF-enriched bacteria included members of Blautia_A (e.g., B. wexlerae, B. massiliensis, and B. obeum), Dorea (e.g., D. longicatena and D. formicigenerans), Streptococcus, Erysipelatoclostridium, while some species of Bacteroides (e.g., B. finegoldii and B. thetaiotaomicron), Faecalibacterium (mainly F. prausnitzii), and Bacteroides_A (e.g., B. plebeius_A and B. coprophilus) were depleted in patients. Fungi such as Malassezia spp. (e.g., M. japonica and M. sympodialis), Candida spp. (e.g., C. parapsilosis), and Mucor circinelloides were more abundant in CHB-LF patients, while Mucor irregularis, Phialophora verrucosa, Hortaea werneckii, and Aspergillus fumigatus were decreases. The CHB-LF-enriched viruses contained 18 Siphoviridae, 12 Myoviridae, and 1 Podoviridae viruses, while the control-enriched viruses included 16 Siphoviridae, 9 Myoviridae, 2 Quimbyviridae, and 1 Podoviridae_crAss-like members. Moreover, we revealed that the CHB-LF-associated gut multi-kingdom signatures were tightly interconnected, suggesting that they may act together on the disease. Finally, we showed that the microbial signatures were effective in discriminating the patients from healthy controls, suggesting the potential of gut microbiota in the prediction of CHB-LF and related diseases.

Discussion

In conclusion, our findings delineated the fecal bacteriome, mycobiome, and virome landscapes of the CHB-LF microbiota and provided biomarkers that will aid in future mechanistic and clinical intervention studies.

Adipose-derived mesenchymal stem cells inhibit hepatic stellate cells activation to alleviate liver fibrosis via Hippo pathway

BACKGROUND

Liver fibrosis is a common pathological process of chronic liver disease, characterized by excessive deposition of extracellular matrix (ECM). Mesenchymal stem cells (MSCs) have been found to have potential therapy effect on liver fibrosis, but the mechanism involved was still unclear. The objective of this study is to investigate the therapeutic efficacy of adipose-derived mesenchymal stem cells (ADMSCs) on the treatment of liver fibrosis, with particular emphasis on elucidating the underlying mechanism of action through which ADMSCs inhibit the activation of hepatic stellate cells (HSCs).

METHODS

ADMSCs were isolated from adipose tissue and injected intravenously into hepatic fibrosis model of rats. The histopathological changes, liver function, collagen deposition, the expression of fibroin and Hippo pathway were evaluated. In vitro, ADMSCs were co-cultured with HSCs activated by transforming growth factor beta 1 (TGF-β1), and the inhibitor of Hippo pathway was used to evaluate the therapeutic mechanism of ADMSCs transplantation.

RESULTS

The results showed that after the transplantation of ADMSCs, the liver function of rats was improved, the degree of liver fibrosis and collagen deposition were reduced, and the Hippo signaling pathway was activated. In vitro, ADMSCs can effectively inhibit the proliferation and activation of HSCs induced by TGF-β1 treatment. However, the inhibitory effect of ADMSCs was weakened after blocking the Hippo signaling pathway.

CONCLUSIONS

ADMSCs inhibit HSCs activation by regulating YAP/TAZ, thereby promoting functional recovery after liver fibrosis. These findings lay a foundation for further investigation into the precise mechanism by which ADMSCs alleviate liver fibrosis.

Multiplex Collagen Fingerprinting for the Staging of Hepatic Fibrosis Using High-Precision Fluorescence-Guided SERS Imaging

Hepatic fibrosis is a common chronic liver disease, and its severe progression can culminate in cirrhosis and hepatocellular carcinoma (HCC). Precise diagnosis and staging of hepatic fibrosis are essential to prevent liver cirrhosis and HCC. Simultaneous detection of multiplex collagen biomarkers within liver tissue is crucial for staging hepatic fibrosis. We herein for the first time constructed multiplex collagen fingerprinting for the staging of hepatic fibrosis using high-precision fluorescence-guided surface-enhanced Raman scattering (SERS) imaging. SERS/fluorescent probes, collectively referred to as SF, comprising silver nanoparticles (Ag NPs), Raman reporters, and FAM-labeled collagen targeting peptides. These probes exhibit exceptional aqueous dispersion and stability, attributed to the increased number of Asp residues in CTP. Meanwhile, SF probes, namely SF-I, SF-IV, and SF-D have demonstrated specific targeting of type I, type IV, and denatured collagen, respectively, within hepatic fibrotic tissues. The results from fluorescence-guided SERS imaging underscore the method's capacity for typing, localization, and quantification of collagen, thus providing novel insights into collagen's role in the development of hepatic fibrosis. The collagen fingerprinting strategy offers a potent toolkit for the multifaceted profiling of collagen superfamilies, holding significant implications for the precise staging of hepatic fibrosis.

A robust collagen-targeting MRI peptide contrast agent for in vivo imaging of hepatic fibrosis

We herein report the construction of a robust MRI peptide contrast agent Gd-ICTP with superior selectivity for type I collagen, enabling the accurate and non-invasive detection of hepatic fibrosis in vivo.

Gentiana decoction inhibits liver fibrosis and the activation of hepatic stellate cells via upregulating the expression of Parkin

Liver fibrosis is a wound-healing process. It can be induced by various chronic liver diseases. Liver fibrosis is characterized by the activation of hepatic stellate cells (HSCs), a key event. However, no effective treatment strategies to cure or alleviate liver fibrosis-induced pathologic changes have yet been developed. Traditional Chinese medicine (TCM) exhibits a good anti-fibrosis action, with few side effects. Gentiana decoction, a TCM also called Longdan Xiegan Tang (LXT), is used for purging the liver in clinical settings. However, the role of LXT in preventing liver fibrosis and the underlying regulatory mechanism have not yet been investigated. This study demonstrates that LXT treatment can protect the liver from the injuries resulting from CCl4-induced liver fibrosis in mice and suppress the activation of HSCs. The mice in the LXT group exhibit litter collagen I and HSC activation marker α-smooth muscle actin (α-SMA) expression. Transcriptome sequencing of the mouse liver tissue reveals that the level of Parkin, a mitophagy marker, decreased in CCl4-induced liver fibrosis. Further study shows that the injection of Parkin-overexpression adeno-associated virus (Parkin-AAV) via the tail vein can reduce CCl4-induced liver fibrogenesis in mice. We conducted a mechanistic study also, which suggests that LXT treatment suppresses the activation of HSCs by upregulating the expression of Parkin. Hence, it can be suggested that LXT inhibits liver fibrosis by activating the Parkin signaling pathway.

NADPH oxidase 4 deficiency promotes hepatocellular carcinoma arising from hepatic fibrosis by inducing M2-macrophages in the tumor microenvironment

Hepatocellular carcinoma (HCC) often arises in the cirrhotic livers, highlighting the intricate link between hepatic fibrosis and carcinogenesis. Reactive oxygen species produced by NADPH oxidase 4 (NOX4) contribute to liver injury leading to hepatic fibrosis. Paradoxically, NOX4 is known to inhibit HCC progression. This study aims to elucidate the role of NOX4 in hepatocarcinogenesis in the background of hepatic fibrosis. We established the mouse model of HCC arising from the fibrotic liver by administering diethylnitrosamine and carbon tetrachloride to wild-type (WT) or NOX4-/- mice. Hepatic fibrogenesis, tumorigenesis, and macrophage polarization were assessed by immunohistochemistry, PCR, and flow cytometry using in vivo and in vitro models. In NOX4-/- mice, hepatic fibrosis was attenuated, while the number of tumors and the proliferation of HCC cells were increased compared to WT mice. Notably, a significant increase in M2-polarized macrophages was observed in NOX4-/- mice through immunohistochemistry and PCR analysis. Subsequent experiments demonstrated that NOX4-silenced HCC cells promote macrophage polarization toward M2. In addition to attenuating hepatic fibrogenesis, NOX4 deficiency triggers macrophage polarization towards the M2 phenotype in the fibrotic liver, thereby promoting hepatocellular carcinogenesis. These findings provide novel insights into the mechanism of NOX4-mediated tumor suppression in HCC arising from fibrotic livers.

C23 ameliorates carbon tetrachloride-induced liver fibrosis in mice

BACKGROUND

C23, an oligo-peptide derived from cold-inducible RNA-binding protein (CIRP), has been reported to inhibit tissue inflammation, apoptosis and fibrosis by binding to the CIRP receptor; however, there are few reports on its role in liver fibrosis and the underlying mechanism is unknown.

AIM

To explore whether C23 plays a significant role in carbon tetrachloride (CCl4)-induced liver fibrosis.

METHODS

CCl4 was injected for 6 weeks to induce liver fibrosis and C23 was used beginning in the second week. Masson and Sirius red staining were used to examine changes in fiber levels. Inflammatory factors in the liver were detected and changes in α-smooth muscle actin (α-SMA) and collagen I expression were detected via immunohistochemical staining to evaluate the activation of hematopoietic stellate cells (HSCs). Western blotting was used to detect the activation status of the transforming growth factor-beta (TGF-β)/Smad3 axis after C23 treatment.

RESULTS

CCl4 successfully induced liver fibrosis in mice, while tumor necrosis factor-alpha (TNF-α), IL (interleukin)-1β, and IL-6 levels increased significantly and the IL-10 level decreased significantly. Interestingly, C23 inhibited this process. On the other hand, C23 significantly inhibited the activation of HSCs induced by CCl4, which inhibited the expression of α-SMA and the synthesis of collagen I. In terms of mechanism, C23 can block Smad3 phosphorylation significantly and inhibits TGF-β/Smad3 pathway activation, thereby improving liver injury caused by CCl4.

CONCLUSION

C23 may block TGF-β/Smad3 axis activation, inhibit the expression of inflammatory factors, and inhibit the activation of HSCs induced by CCl4, alleviating liver fibrosis.

Nanogene editing drug delivery systems in the treatment of liver fibrosis

Liver fibrosis is a group of diseases that seriously affect the health of the world's population. Despite significant progress in understanding the mechanisms of liver fibrogenesis, the technologies and drugs used to treat liver fibrosis have limited efficacy. As a revolutionary genetic tool, gene editing technology brings new hope for treating liver fibrosis. Combining nano-delivery systems with gene editing tools to achieve precise delivery and efficient expression of gene editing tools that can be used to treat liver fibrosis has become a rapidly developing field. This review provides a comprehensive overview of the principles and methods of gene editing technology and commonly used gene editing targets for liver fibrosis. We also discuss recent advances in common gene editing delivery vehicles and nano-delivery formulations in liver fibrosis research. Although gene editing technology has potential advantages in liver fibrosis, it still faces some challenges regarding delivery efficiency, specificity, and safety. Future studies need to address these issues further to explore the potential and application of liver fibrosis technologies in treating liver fibrosis.

Pyroptosis in health and disease: mechanisms, regulation and clinical perspective

Pyroptosis is a type of programmed cell death characterized by cell swelling and osmotic lysis, resulting in cytomembrane rupture and release of immunostimulatory components, which play a role in several pathological processes. Significant cellular responses to various stimuli involve the formation of inflammasomes, maturation of inflammatory caspases, and caspase-mediated cleavage of gasdermin. The function of pyroptosis in disease is complex but not a simple angelic or demonic role. While inflammatory diseases such as sepsis are associated with uncontrollable pyroptosis, the potent immune response induced by pyroptosis can be exploited as a therapeutic target for anti-tumor therapy. Thus, a comprehensive review of the role of pyroptosis in disease is crucial for further research and clinical translation from bench to bedside. In this review, we summarize the recent advancements in understanding the role of pyroptosis in disease, covering the related development history, molecular mechanisms including canonical, non-canonical, caspase 3/8, and granzyme-mediated pathways, and its regulatory function in health and multiple diseases. Moreover, this review also provides updates on promising therapeutic strategies by applying novel small molecule inhibitors and traditional medicines to regulate pyroptosis. The present dilemmas and future directions in the landscape of pyroptosis are also discussed from a clinical perspective, providing clues for scientists to develop novel drugs targeting pyroptosis.

A FAPα-activated MRI nanoprobe for precise grading diagnosis of clinical liver fibrosis

Molecular imaging holds the potential for noninvasive and accurate grading of liver fibrosis. It is limited by the lack of biomarkers that strongly correlate with liver fibrosis grade. Here, we discover the grading potential of fibroblast activation protein alpha (FAPα) for liver fibrosis through transcriptional analysis and biological assays on clinical liver samples. The protein and mRNA expression of FAPα are linearly correlated with fibrosis grade (R2 = 0.89 and 0.91, respectively). A FAPα-responsive MRI molecular nanoprobe is prepared for quantitatively grading liver fibrosis. The nanoprobe is composed of superparamagnetic amorphous iron nanoparticles (AFeNPs) and paramagnetic gadoteric acid (Gd-DOTA) connected by FAPα-responsive peptide chains (ASGPAGPA). As liver fibrosis worsens, the increased FAPα cut off more ASGPAGPA, restoring a higher T1-MRI signal of Gd-DOTA. Otherwise, the signal remains quenched due to the distance-dependent magnetic resonance tuning (MRET) effect between AFeNPs and Gd-DOTA. The nanoprobe identifies F1, F2, F3, and F4 fibrosis, with area under the curve of 99.8%, 66.7%, 70.4%, and 96.3% in patients' samples, respectively. This strategy exhibits potential in utilizing molecular imaging for the early detection and grading of liver fibrosis in the clinic.

Effect of an Autotaxin Inhibitor, 2-(4-Chlorophenyl)-7-methyl-8-pentylimidazo[1,2-a] Pyrimidin-5(8H)-one (CBT-295), on Bile Duct Ligation-Induced Chronic Liver Disease and Associated Hepatic Encephalopathy in Rats

The role of autotaxin (ATX)-lysophosphatidic acid (LPA) is yet to be explored in the context of liver cirrhosis and associated encephalopathy. Our objective of this study was to evaluate the role of an ATX inhibitor in biliary cirrhosis and associated hepatic encephalopathy in rats. The preliminary investigation revealed significant impairment in liver function, which eventually led to the development of hepatic encephalopathy. Interestingly, LPA levels were significantly increased in the plasma, liver, and brain of rats following bile duct ligation. Subsequently, we tested the efficacy of an ATX inhibitor, CBT-295, in bile duct-induced biliary cirrhosis and neuropsychiatric symptoms associated with hepatic encephalopathy. CBT-295 showed good oral bioavailability and favorable pharmacokinetic properties. CBT-295 exhibited a significant reduction in inflammatory cytokines like TGF-β, TNF-α, and IL-6 levels, also reduced bile duct proliferation marker CK-19, and lowered liver fibrosis, as evident from reduced collagen deposition. The reversal of liver fibrosis with CBT-295 led to a reduction in blood and brain ammonia levels. Furthermore, CBT-295 also reduced neuroinflammation induced by ammonia, which is characterized by a significant reduction in brain cytokine levels. It improved neuropsychiatric symptoms such as locomotor activities, cognitive impairment, and clinical grading scores associated with hepatic encephalopathy. The improvement in hepatic encephalopathy observed with the ATX inhibitor could be the result of its hepatoprotective action and its ability to attenuate neuroinflammation. Therefore, inhibition of ATX-LPA signaling can be a multifactorial approach for the treatment of chronic liver diseases.

Muscular hyperplasia in Crohn's disease strictures: through thick and thin

Fibrostenosing Crohn's disease (CD) represents a challenging clinical condition characterized by the development of symptomatic strictures within the gastrointestinal tract. Despite therapeutic advancements in managing inflammation, the progression of fibrostenotic complications remains a significant concern, often necessitating surgical intervention. Recent investigations have unveiled the pivotal role of smooth muscle cell hyperplasia in driving luminal narrowing and clinical symptomatology. Drawing parallels to analogous inflammatory conditions affecting other organs, such as the airways and blood vessels, sheds light on common underlying mechanisms of muscular hyperplasia. This review synthesizes current evidence to elucidate the mechanisms underlying smooth muscle cell proliferation in CD-associated strictures, offering insights into potential therapeutic targets. By highlighting the emerging significance of muscle thickening as a novel therapeutic target, this review aims to inform future research endeavors and clinical strategies with the goal to mitigate the burden of fibrostenotic complications in CD and other conditions.

Liver fibrosis analysis using digital pathology

Digital pathology has enabled the noninvasive quantification of pathological parameters. In addition, the combination of digital pathology and artificial intelligence has enabled the analysis of a vast amount of information, leading to the sharing of much information and the elimination of knowledge gaps. Fibrosis, which reflects chronic inflammation, is the most important pathological parameter in chronic liver diseases, such as viral hepatitis and metabolic dysfunction-associated steatotic liver disease. It has been reported that the quantitative evaluation of various fibrotic parameters by digital pathology can predict the prognosis of liver disease and hepatocarcinogenesis. Liver fibrosis evaluation methods include 1 fiber quantification, 2 elastin and collagen quantification, 3 s harmonic generation/two photon excitation fluorescence (SHG/TPE) microscopy, and 4 Fibronest™..　In this review, we provide an overview of role of digital pathology on the evaluation of fibrosis in liver disease and the characteristics of recent methods to assess liver fibrosis.

Extracellular Vesicle-Associated Neutrophil Elastase Activates Hepatic Stellate Cells and Promotes Liver Fibrogenesis via ERK1/2 Pathway

Liver fibrosis associated with increased mortality is caused by activation of hepatic stellate cells and excessive production and accumulation of extracellular matrix in response to fibrotic insults. It has been shown that in addition to liver inflammation, systemic inflammation also contributes to liver fibrogenesis. A deeper understanding of mechanisms that control liver fibrotic response to intra- and extra-hepatic inflammation is essential to develop novel clinical strategies against this disease. Extracellular vesicles (EV) have been recognized as immune mediators that facilitate activation of hepatic stellate cells. In inflammatory diseases, activated neutrophils release neutrophil elastase (NE) bound to EV, which has been identified as a significant contributor to inflammation by promoting immune cell activation. Here, we aimed to explore the role of inflammation derived plasma EV-associated NE in liver fibrogenesis and its potential mechanisms. We show EV-associated NE induces activation, proliferation and migration of hepatic stellate cells by promoting activation of the ERK1/2 signaling pathway. This effect did not occur through EV without surface NE, and Sivelestat, a NE inhibitor, inhibited activation of the ERK1/2 signaling pathway mediated by EV-associated NE. Moreover, we found plasma EV-associated NE increases deposition of collagen1 and α-smooth muscle actin in the liver of a mouse model of liver fibrosis (Mdr2-/-). Notably, this effect does not occur in control mice without preexisting liver disease. These data suggest that EV-associated NE is a pro-fibrogenic factor for hepatic stellate cell activation via the ERK1/2 signaling pathway in pre-existing liver injuries. Inhibition of the plasma EV-associated NE in inflammatory conditions may be a therapeutic target for liver fibrosis in patients with inflammatory diseases.

Pathogenesis and interaction of neutrophils and extracellular vesicles in noncancer liver diseases

Liver disease ranks as the eleventh leading cause of mortality, leading to approximately 2 million deaths annually worldwide. Neutrophils are a type of immune cell that are abundant in peripheral blood and play a vital role in innate immunity by quickly reaching the site of liver injury. They exert their influence on liver diseases through autocrine, paracrine, and immunomodulatory mechanisms. Extracellular vesicles, phospholipid bilayer vesicles, transport a variety of substances, such as proteins, nucleic acids, lipids, and pathogenic factors, for intercellular communication. They regulate cell communication and perform their functions by delivering biological information. Current research has revealed the involvement of the interaction between neutrophils and extracellular vesicles in the pathogenesis of liver disease. Moreover, more research has focused on targeting neutrophils as a therapeutic strategy to attenuate disease progression. Therefore, this article summarizes the roles of neutrophils, extracellular vesicles, and their interactions in noncancerous liver diseases.

To elucidate the bioactive components of Lamiophlomis herba in the treatment of liver fibrosis via plasma pharmacochemistry and network pharmacology

Lamiophlomis Herba (LH) is a traditional Chinese and Tibetan dual-use herb with hemostatic and analgesic effects, and is widely used in the clinical treatment of traumatic bleeding and pain. In recent years, LH has been proven to treat liver fibrosis (LF), but the chemical components related to the pharmacological properties of LH in the treatment of LF are still unclear. Based on the theory of plasma pharmachemistry, the characteristic components in water extract and drug-containing plasma samples of LH were qualitatively analyzed by UPLC-Q-TOF-MS. The chemical components in plasma were screened and the targets were predicted by network pharmacology. Then, the predicted components and targets were verified in vitro by Elisa and qRT-PCR technology. Finally, the pharmacological effects of LH and its monomeric components were determined by hematoxylin-eosin staining of rat liver. A total of 50 chemical constituents were identified in LH, of which 12 were blood prototypes and 9 were metabolites. In vitro experiments showed that LH and its monomeric components luteolin, shanzhiside methyl ester, loganic acid, loganin, 8-O-acetyl shanzhiside methyl ester could increase the expression of antioxidant genes (NQO-1, HO-1) and decrease the expression of inflammatory genes (IL-6, IL-18), thereby reducing the expression of extracellular matrix-related genes and proteins (COL1A1, COL3A1, LN, α-sma, PC-III, Col-IV). In vivo experiments showed that LH could reduce the area of LF in rats in a dose-dependent manner, and shanzhiside methyl ester and 8-O-acetyl shanzhiside methyl ester may be the main components in pharmacodynamics. These effects may be mediated by LH-mediated Nrf2/NF-κB pathway. This study explored the potential pharmacodynamic components of LH in the treatment of LF, and confirmed that shanzhiside methyl ester and 8-O-acetyl shanzhiside methyl ester play a key role in the treatment of LF with LH.

Role of the type 3 cytokines IL-17 and IL-22 in modulating metabolic dysfunction-associated steatotic liver disease

Metabolic dysfunction-associated steatotic liver disease (MASLD) comprises a spectrum of liver diseases that span simple steatosis, metabolic dysfunction-associated steatohepatitis (MASH) and fibrosis and may progress to cirrhosis and cancer. The pathogenesis of MASLD is multifactorial and is driven by environmental, genetic, metabolic and immune factors. This review will focus on the role of the type 3 cytokines IL-17 and IL-22 in MASLD pathogenesis and progression. IL-17 and IL-22 are produced by similar adaptive and innate immune cells such as Th17 and innate lymphoid cells, respectively. IL-17-related signaling is upregulated during MASLD resulting in increased chemokines and proinflammatory cytokines in the liver microenvironment, enhanced recruitment of myeloid cells and T cells leading to exacerbation of inflammation and liver disease progression. IL-17 may also act directly by activating hepatic stellate cells resulting in increased fibrosis. In contrast, IL-22 is a pleiotropic cytokine with a dominantly protective signature in MASLD and is currently being tested as a therapeutic strategy. IL-22 also exhibits beneficial metabolic effects and abrogates MASH-related inflammation and fibrosis development via inducing the production of anti-oxidants and anti-apoptotic factors. A sex-dependent effect has been attributed to both cytokines, most importantly to IL-22 in MASLD or related conditions. Altogether, IL-17 and IL-22 are key effectors in MASLD pathogenesis and progression. We will review the role of these two cytokines and cells that produce them in the development of MASLD, their interaction with host factors driving MASLD including sexual dimorphism, and their potential therapeutic benefits.

Advancements of non‐invasive imaging technologies for the diagnosis and staging of liver fibrosis: Present and future

Liver fibrosis is a reparative response triggered by liver injury. Non‐invasive assessment and staging of liver fibrosis in patients with chronic liver disease are of paramount importance, as treatment strategies and prognoses depend significantly on the degree of fibrosis. Although liver fibrosis has traditionally been staged through invasive liver biopsy, this method is prone to sampling errors, particularly when biopsy sizes are inadequate. Consequently, there is an urgent clinical need for an alternative to biopsy, one that ensures precise, sensitive, and non‐invasive diagnosis and staging of liver fibrosis. Non‐invasive imaging assessments have assumed a pivotal role in clinical practice, enjoying growing popularity and acceptance due to their potential for diagnosing, staging, and monitoring liver fibrosis. In this comprehensive review, we first delved into the current landscape of non‐invasive imaging technologies, assessing their accuracy and the transformative impact they have had on the diagnosis and management of liver fibrosis in both clinical practice and animal models. Additionally, we provided an in‐depth exploration of recent advancements in ultrasound imaging, computed tomography imaging, magnetic resonance imaging, nuclear medicine imaging, radiomics, and artificial intelligence within the field of liver fibrosis research. We summarized the key concepts, advantages, limitations, and diagnostic performance of each technique. Finally, we discussed the challenges associated with clinical implementation and offer our perspective on advancing the field, hoping to provide alternative directions for the future research.

Progranulin: A promising biomarker and therapeutic target for fibrotic diseases

Progranulin (PGRN), a multifunctional growth factor-like protein expressed by a variety of cell types, serves an important function in the physiologic and pathologic processes of fibrotic diseases, including wound healing and the inflammatory response. PGRN was discovered to inhibit pro-inflammation effect by competing with tumor necrosis factor-alpha (TNF-α) binding to TNF receptors. Notably, excessive tissue repair in the development of inflammation causes tissue fibrosis. Previous investigations have indicated the significance of PGRN in regulating inflammatory responses. Recently, multiple studies have shown that PGRN was linked to fibrogenesis, and was considered to monitor the formation of fibrosis in multiple organs, including liver, cardiovascular, lung and skin. This paper is a comprehensive review summarizing our current knowledge of PGRN, from its discovery to the role in fibrosis. This is followed by an in-depth look at the characteristics of PGRN, consisting of its structure, basic function and intracellular signaling. Finally, we will discuss the potential of PGRN in the diagnosis and treatment of fibrosis.

Single-cell RNA sequencing reveals reduced intercellular adhesion molecule crosstalk between activated hepatic stellate cells and neutrophils alleviating liver fibrosis in hepatitis B virus transgenic mice post menstrual blood-derived mesenchymal stem cell transplantation

Liver fibrosis can cause hepatitis B virus (HBV)-associated hepatocellular carcinoma. Menstrual blood-derived mesenchymal stem cells (MenSCs) can ameliorate liver fibrosis through paracrine. Single-cell RNA sequencing (scRNA-seq) may be used to explore the roadmap of activated hepatic stellate cell (aHSC) inactivation to target liver fibrosis. This study established HBV transgenic (HBV-Tg) mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis and demonstrated that MenSCs migrated to the injured liver to improve serological indices and reduce fibrotic accumulation. RNA-bulk analysis revealed that MenSCs mediated extracellular matrix accumulation and cell adhesion. Liver parenchymal cells and nonparenchymal cells were identified by scRNA-seq in the control, CCl4, and MenSC groups, revealing the heterogeneity of fibroblasts/HSCs. A CellChat analysis revealed that diminished intercellular adhesion molecule (ICAM) signaling is vital for MenSC therapy. Specifically, Icam1 in aHSCs acted on Itgal/Itgb2 and Itgam/Itgb2 in neutrophils, causing decreased adhesion. The expression of Itgal, Itgam, and Itgb2 was higher in CCl4 group than in the control group and decreased after MenSC therapy in neutrophil clusters. The Lcn2, Pglyrp1, Wfdc21, and Mmp8 had high expression and may be potential targets in neutrophils. This study highlights interacting cells, corresponding molecules, and underlying targets for MenSCs in treating HBV-associated liver fibrosis.

Farnesoid X receptor: From Structure to Function and Its Pharmacology in Liver Fibrosis

The farnesoid X receptor (FXR), a ligand-activated transcription factor, plays a crucial role in regulating bile acid metabolism within the enterohepatic circulation. Beyond its involvement in metabolic disorders and immune imbalances affecting various tissues, FXR is implicated in microbiota modulation, gut-to-brain communication, and liver disease. The liver, as a pivotal metabolic and detoxification organ, is susceptible to damage from factors such as alcohol, viruses, drugs, and high-fat diets. Chronic or recurrent liver injury can culminate in liver fibrosis, which, if left untreated, may progress to cirrhosis and even liver cancer, posing significant health risks. However, therapeutic options for liver fibrosis remain limited in terms of FDA-approved drugs. Recent insights into the structure of FXR, coupled with animal and clinical investigations, have shed light on its potential pharmacological role in hepatic fibrosis. Progress has been achieved in both fundamental research and clinical applications. This review critically examines recent advancements in FXR research, highlighting challenges and potential mechanisms underlying its role in liver fibrosis treatment.