Targeting GPR65 alleviates hepatic inflammation and fibrosis by suppressing the JNK and NF-κB pathways

Background:G-protein coupled receptors(GPCRs)are recognized as attractive targets for drug therapy.However,it remains poorly understood how GPCRs,except for a few chemokine receptors,regulate the progression of liver fibrosis.Here,we aimed to reveal the role of GPR65,a proton-sensing receptor,in liver fibrosis and to elucidate the underlying mechanism.Methods:The expression level of GPR65 was evaluated in both human and mouse fibrotic livers.Furthermore,Gpr65-deficient mice were treated with either bile duct ligation(BDL)for 21 d or carbon tetrachloride(CCl4)for 8 weeks to investigate the role of GPR65 in liver fibrosis.A combination of experimental approaches,including Western blotting,quantitative real-time reverse transcription-polymerase chain reaction(qRT-PCR),and enzyme-linked immunosorbent assay(ELISA),confocal microscopy and rescue studies,were used to explore the underlying mechanisms of GPR65’s action in liver fibrosis.Additionally,the therapeutic potential of GPR65 inhibitor in the development of liver fibrosis was investigated.Results:We found that hepatic macrophage(HM)-enriched GPR65 was upregulated in both human and mouse fibrotic livers.Moreover,knockout of Gpr65 significantly alleviated BDL-and CCl4-induced liver inflammation,injury and fibrosis in vivo,and mouse bone marrow transplantation(BMT)experiments further demonstrated that the protective effect of Gpr65knockout is primarily mediated by bone marrow-derived macrophages(BMMs).Additionally,in vitro data demonstrated that Gpr65 silencing and GPR65 antagonist inhibited,while GPR65 overexpression and application of GPR65 endogenous and exogenous agonists enhanced the expression and release of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6)and transforming growth factor-β(TGF-β),all of which subsequently promoted the activation of hepatic stellate cells(HSCs)and the damage of hepatocytes(HCs).Mechanistically,GPR65 overexpression,the acidic pH and GPR65 exogenous agonist induced up-regulation of TNF-αand IL-6 via the Gαq-Ca^(2+)-JNK/NF-κB pathways,while promoted the expression of TGF-βthrough the Gαq-Ca^(2+)-MLK3-MKK7-JNK pathway.Notably,pharmacological GPR65 inhibition retarded the development of inflammation,HCs injury and fibrosis invivo.Conclusions:GPR65 is a major regulator that modulates the progression of liver fibrosis.Thus,targeting GPR65 could be an effective therapeutic strategy for the prevention of liver fibrosis.

Improvement of hepatic fibrosis after tenofovir disoproxil fumarate switching to tenofovir alafenamide for three years

BACKGROUND Both tenofovir alafenamide(TAF)and tenofovir disoproxil fumarate(TDF)are the first-line treatments for chronic hepatitis B(CHB).We have showed switching from TDF to TAF for 96 weeks resulted in further alanine aminotransferase(ALT)improvement,but data remain lacking on the long-term benefits of TDF switching to TAF on hepatic fibrosis.AIM To assess the benefits of TDF switching to TAF for 3 years on ALT,aspartate aminotransferase(AST),and hepatic fibrosis improvement in patients with CHB.METHODS A single center retrospective study on 53 patients with CHB who were initially treated with TDF,then switched to TAF to determine dynamic patterns of ALT,AST,AST to platelet ratio index(APRI),fibrosis-4(FIB-4)scores,and shear wave elastography(SWE)reading improvement at switching week 144,and the associated factors.RESULTS The mean age was 55(28-80);45.3%,males;15.1%,clinical cirrhosis;mean baseline ALT,24.8;AST,25.7 U/L;APRI,0.37;and FIB-4,1.66.After 144 weeks TDF switching to TAF,mean ALT and AST were reduced to 19.7 and 21,respectively.From baseline to switching week 144,the rates of ALT and AST<35(male)/25(female)and<30(male)/19(female)were persistently increased;hepatic fibrosis was also improved by APRI<0.5,from 79.2%to 96.2%;FIB-4<1.45,from 52.8%to 58.5%,respectively;mean APRI was reduced to 0.27;FIB-4,to 1.38;and mean SWE reading,from 7.05 to 6.30 kPa after a mean of 109 weeks switching.The renal function was stable and the frequency of patients with glomerular filtration rate>60 mL/min was increased from 86.5%at baseline to 88.2%at switching week 144.CONCLUSION Our data confirmed that switching from TDF to TAF for 3 years results in not only persistent ALT/AST improvement,but also hepatic fibrosis improvement by APRI,FIB-4 scores,as well as SWE reading,the important clinical benefits of long-term hepatitis B virus antiviral treatment with TAF.

Ginsenoside Rb1 induces hepatic stellate cell ferroptosis to alleviate liver fibrosis via the BECN1/SLC7A11 axis

Liver fibrosis is primarily driven by the activation of hepatic stellate cells(HSCs),a process associated with ferroptosis.Ginsenoside Rb1(GRb1),a major active component extracted from Panax ginseng,inhibits HSC activation.However,the potential role of GRb1 in mediating HSC ferroptosis remains unclear.This study examined the effect of GRb1 on liver fibrosis both in vivo and in vitro,using CCl4-induced liver fibrosis mouse model and primary HSCs,LX-2 cells.The findings revealed that GRb1 effectively inactivated HSCs in vitro,reducing alpha-smooth muscle actin(a-SMA)and type I collagen(Col1A1)levels.Moreover,GRb1 significantly alleviated CCl4-induced liver fibrosis in vivo.From a mechanistic standpoint,the ferroptosis pathway appeared to be central to the antifibrotic effects of GRb1.Specifically,GRb1 promoted HSC ferroptosis both in vivo and in vitro,characterized by increased glutathione depletion,malondialdehyde production,iron overload,and accumulation of reactive oxygen species(ROS).Intriguingly,GRb1 increased Beclin 1(BECN1)levels and decreased the System Xc-key subunit SLC7A11.Further experiments showed that BECN1 silencing inhibited GRb1-induced effects on HSC ferroptosis and mitigated the reduction of SLC7A11 caused by GRb1.Moreover,BECN1 could directly interact with SLC7A11,initiating HSC ferroptosis.In conclusion,the suppression of BECN1 counteracted the effects of GRb1 on HSC inactivation both in vivo and in vitro.Overall,this study highlights the novel role of GRb1 in inducing HSC ferroptosis and promoting HSC inactivation,at least partly through its modulation of BECN1 and SLC7A11.

Evaluation of Hepatic Fibrosis and Hepatic Steatosis by Pulse Elastography (FIBROSCAN/CAP) in Asymptomatic Patients about 170 Cases at the Donka CHU National Hospital in Conakry

Introduction: Fibroscan is a recent, non-invasive and non-irradiating diagnostic method. It is based on the principle of ultrasound, which enables liver tissue elasticity to be quantified using a probe, and fibrosis to be assessed. Fibroscan measures both elasticity correlated with hepatic fibrosis and CAP correlated with steatosis. The aim of this study was to evaluate hepatic fibrosis and steatosis using pulse elastometry (Fibroscan/CAP). Methods: This was a descriptive and analytical cross-sectional study in which 170 patients were included. It was conducted from October 1 2021 to December 31 2023, i.e. 27 months, in an outpatient clinic in the hepato-gastroenterology department of the Donka national hospital of the CHU Conakry. Results: Of the 170 patients identified, 87 were male (51%) and 83 female (49%), giving a M/F sex ratio of 1.04. The average age of our patients was 40. The 30 - 50 age group was the most affected, with a frequency of 58.23% (n = 99), followed by the 50 age group with a frequency of 29.41% (n = 50). Hepatomegaly, steatotic liver on ultrasonography, transaminase elevation and obesity were the main indications, respectively: (21.76%), (17.65%), (14.71%), and (13.53%). The examinations were requested by hepatogastroenterologists (47.06%), diabetologists (35.88%) and general practitioners (29%). Of the 170 patients, 100 patients (58.82%) had no significant fibrosis F0F1, 39 (22.94%) had moderate fibrosis F2, 20 patients (11.76%) had severe fibrosis F3 and 11 patients (6.47%) had fibrosis F4. Hepatic steatosis: 62 patients (36.47%) had no S0 steatosis;29.41% had S1 steatosis, 20% had S2 steatosis and 24 patients (14.11%) had S3 steatosis. Abdominal ultrasound revealed a normal liver in 67.05% of patients, hepatic steatosis in 29.41% and non-decompensated cirrhosis in 6 cases. Thus, 108 patients had the parameters required to calculate the Fatty Liver Index (FLI), steatosis was present in 20% of our patients, while 29.41% had an undetermined status and 24 14.11% had a normal FLI. Conclusion: Identifying subjects at risk of metabolic steatopathy, diagnosing and managing these patients is a public health issue and one of the future challenges of hepato-gastroenterology. Fibroscan is an increasingly popular screening tool for hepatic fibrosis and steatosis. The fight against obesity must be a priority.

HepG2.2.15-derived exosomes facilitate the activation and fibrosis of hepatic stellate cells

BACKGROUND The role of exosomes derived from HepG2.2.15 cells,which express hepatitis B virus(HBV)-related proteins,in triggering the activation of LX2 liver stellate cells and promoting liver fibrosis and cell proliferation remains elusive.The focus was on comprehending the relationship and influence of differentially expressed microRNAs(DE-miRNAs)within these exosomes.AIM To elucidate the effect of exosomes derived from HepG2.2.15 cells on the activation of hepatic stellate cell(HSC)LX2 and the progression of liver fibrosis.METHODS Exosomes from HepG2.2.15 cells,which express HBV-related proteins,were isolated from parental HepG2 and WRL68 cells.Western blotting was used to confirm the presence of the exosomal marker protein CD9.The activation of HSCs was assessed using oil red staining,whereas DiI staining facilitated the observation of exosomal uptake by LX2 cells.Additionally,we evaluated LX2 cell proliferation and fibrosis marker expression using 5-ethynyl-2′-deoxyuracil staining and western blotting,respectively.DE-miRNAs were analyzed using DESeq2.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways were used to annotate the target genes of DE-miRNAs.RESULTS Exosomes from HepG2.2.15 cells were found to induced activation and enhanced proliferation and fibrosis in LX2 cells.A total of 27 miRNAs were differentially expressed in exosomes from HepG2.2.15 cells.GO analysis indicated that these DE-miRNA target genes were associated with cell differentiation,intracellular signal transduction,negative regulation of apoptosis,extracellular exosomes,and RNA binding.KEGG pathway analysis highlighted ubiquitin-mediated proteolysis,the MAPK signaling pathway,viral carcinogenesis,and the toll-like receptor signaling pathway,among others,as enriched in these targets.CONCLUSION These findings suggest that exosomes from HepG2.2.15 cells play a substantial role in the activation,proliferation,and fibrosis of LX2 cells and that DE-miRNAs within these exosomes contribute to the underlying mechanisms.

A Discussion on the Relationship among Hepatic Stellate Cells,Hepatic Sinusoidal Endothelial Cells and Hepatic Sinusoidal Capillarization in the Development of Hepatic Fibrosis

Hepatic stellate cells,hepatic sinusoidal endothelial cells and hepatic sinusoidal capllarization are closely related to the occurrence and progression of hepatic fibrosis.The pathological activation of hepatic stellate cels is the central link of hepatic fibrosis,and hepatic sinusoidal capillarization also promotes the occurrence and development of liver diseases.In the course of hepatic fibrosis,there is always a mutually reinforcing relationship between the activation of hepatic stellate cells and the capillarization of hepatic sinusoids.This paper strives to find an effective way to intervene or even reverse this vicious cycle by deeply investigating the effect of hepatic stellate cells and hepatic sinusoidal capillarization on hepatic fibrosis and their mutual promotion,and provide a new idea for the treatment of hepatic fibrosis,which is of great significance for relieving and reversing hepatic fibrosis.

MSC-derived exosomes attenuate hepatic fibrosis in primary sclerosing cholangitis through inhibition of Th17 differentiation

Primary sclerosing cholangitis(PSC)is an autoimmune cholangiopathy characterized by chronic inflammation of the biliary epithelium and periductal fibrosis,with no curative treatment available,and liver transplantation is inevitable for end-stage patients.Human placentalmesenchymal stem cell(hpMSC)-derived exosomes have demonstrated the ability to prevent fibrosis,inhibit collagen production and possess immunomodulatory properties in autoimmune liver disease.Here,we prepared hpMSC-derived exosomes(Exo^(MSC))and further investigated the anti-fibrotic effects and detailed mechanism on PSC based on Mdr2^(−/−)mice and multicellular organoids established from PSC patients.The results showed that Exo^(MSC) ameliorated liver fibrosis in Mdr2^(−/−)mice with significant collagen reduction in the preductal area where Th17 differentiation was inhibited as demonstrated by RNAseq analysis,and the percentage of CD4+IL-17A+T cells was reduced both in Exo^(MSC)-treated Mdr2^(−/−)mice(Mdr2^(−/−)-Exo)in vivo and Exo^(MSC)-treated Th17 differentiation progressed in vitro.Furthermore,Exo^(MSC) improved the hypersecretory phenotype and intercellular interactions in the hepatic Th17 microenvironment by regulating PERK/CHOP signaling as supported by multicellular organoids.Thus,our data demonstrate the antifibrosis effect of Exo^(MSC) in PSC disease by inhibiting Th17 differentiation,and ameliorating the Th17-induced microenvironment,indicating the promising potential therapeutic role of Exo^(MSC) in liver fibrosis of PSC or Th17-related diseases.

Cornus officinalis with high pressure wine steaming enhanced anti-hepatic fibrosis: Possible through SIRT3-AMPK axis

Cornus officinalis,a medicinal and edible plant known for its liver-nourishing properties,has shown promise in inhibiting the activation of hepatic stellate cells(HSCs),crucial indicators of hepatic fibrosis,especially when processed by high pressure wine steaming(HPWS).Herein,this study aims to investigate the regulatory effects of cornus officinalis,both in its raw and HPWS forms,on inflammation and apoptosis in liver fibrosis and their underlying mechanisms.In vivo liver fibrosis models were established by subcutaneous injection of CCl4,while in vitro HSCs were exposed to transforming growth factor-b(TGF-b).These findings demonstrated that cornus officinalis with HPWS conspicuously ameliorated histopathological injury,reduced the release of proinflammatory factors,and decreased collagen deposition in CCl4-induced rats compared to its raw form.Utilizing ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometer(UHPLC-QTOF-MS)combined with network analysis,we identified that the pharmacological effects of the changed components of cornus officinalis before and after HPWS,primarily centered on the adenosine phosphate(AMP)-activated protein kinase(AMPK)pathway.Of note,cornus officinalis activated AMPK and sirtuin 3(SIRT3),promoting the apoptosis of activated HSCs through the caspase cascade by regulating caspase3,caspase6 and caspase9.small interfering RNA(siRNA)experiments showed that cornus officinalis could regulate AMPK activity and its mediated-apoptosis through SIRT3.In conclusion,cornus officinalis exhibited the ability to reduce inflammation and apoptosis,with the SIRT3-AMPK signaling pathway identified as a potential mechanism underlying the synergistic effect of cornus officinalis with HPWS on anti-liver fibrosis.

Research Progress on the Regulation of Hepatic Sinusoidal Endothelial Cells on Hepatic Fibrosis

Hepatic sinusoidal endothelial cell is a highly differentiated cell in hepatic sinusoid,and plays an important role in the occurrence and development of hepatic fibrosis.The dysfunction of hepatic sinusoidal endothelial cells is considered to be the key cause of a variety of liver diseases.At present,the researches on hepatic fibrosis at home and abroad are mainly focused on inhibiting the activation of hepatic stellate cells and accelerating the hydrolysis of extracellular matrix.However,there are few studies on the important role of the structure and function of hepatic sinusoidal endothelial cells in hepatic fibrosis.This paper reviews the research progress on the effect of hepatic sinusoidal endothelial cells on hepatic fibrosis and its regulatory mechanism in recent years.This paper summarizes the results of the research on the structural characteristics of hepatic sinusoidal endothelial cells,secretion of fibrosis-related cytokines and regulation of hepatic stellate cells activation in the development of hepatic fibrosis.

Peroxisome proliferator-activated receptor gamma inhibits hepatic fibrosis in rats

BACKGROUND:Hepatic fibrosis is a necessary step in the development of hepatic cirrhosis.In this study we used lentiviral vector-mediated transfection technology to evaluate the effect of peroxisome proliferator-activated receptor gamma(PPAR-γ) on rat hepatic fibrosis. METHODS:Hepatic fibrosis in rats was induced by CCl4 for 2 weeks(early fibrosis)and 8 weeks(sustained fibrosis).The rats were randomly divided into four groups:normal control, fibrosis,blank vector,and PPAR-γ.They were infected with the recombinant lentiviral expression vector carrying the rat PPAR-γgene by portal vein injection.The liver of the rats was examined histologically and hydroxyproline was assessed.In vitro primary hepatic stellate cells(HSCs)were infected with the recombinant lentiviral expression vector carrying the rat PPAR-γgene.The status of HSC proliferation was measured by the MTT assay.The protein levels of PPAR-γ,α-smooth muscle actin(α-SMA)and type I collagen expression were evaluated by the Western blotting method. RESULTS:In vitro studies revealed that expression of PPAR-γ inhibited expression ofα-SMA and type I collagen in activated HSCs(P<0.01)as well as HSC proliferation(P<0.01).In vivo experiments indicated that in the early hepatic fibrosis group,the hydroxyproline content and the level of collagen I protein in the liver in the PPAR-γtransfected group were not significantly different compared to the hepatic fibrosis group and the blank vector group;whereas the expressions of PPAR-γ andα-SMA were different compared to the hepatic fibrosis group(P<0.01).In the sustained hepatic fibrosis group,there were significant differences in the hydroxyproline content and the expression of PPAR-γ,α-SMA,and type I collagen between each group.CONCLUSION:PPAR-γcan inhibit HSC proliferation and hepatic fibrosis,and suppressα-SMA and type I collagen expression.

Correlation between anti-fibrotic effect of baicalin and serum cytokines in rat hepatic fibrosis

AIM： To investigate the correlation between the antifibrotic effect of baicalin and serum cytokine production in rat hepatic fibrosis, METHODS： Forty male Sprague-Dawley rats were divided randomly into four groups： normal control group, model group, baicalin-treated group, and colchicine-treated group. Except for the normal control group, all rats in the other groups were administered with carbon tetrachloride to induce hepatic fibrosis. At the same time, the last two groups were also treated with baicalin or colchicine. At the end of the 8 wk, all animals were sacrificed. Serum alanine aminotransferase （ALl＇）, aspartate aminotransferase （AST）, transforming growth factor （TGF）-β1, tumor necrosis factor （TNF）-α, interleukin （IL）-6 and IL-10 were measured. Liver index, hepatic hydroxyproline content and the degree of liver fibrosis were also evaluated. RESULTS： The levels of ALT, AST and liver index in the baicalin-treated group were markedly lower than those in the model group （ALT： 143.88 ± 14.55 U/L vs 193.58± 24.35 U/L; AST： 263.66 ± 44.23 U/L vs 404.37± 68.29 U/L; liver index： 0.033 ± 0.005 vs 0.049± 0.009, P 〈 0.01）. Baicalin therapy also significantly attenuated the degree of hepatic fibrosis, collagen area and collagen area percentage in liver tissue （P 〈 0.01）. Furthermore, the levels of serum TGF-β1, TNF-α and IL-6 were strikingly reduced in the baicalin-treated group compared with the model group, while the production of IL-10 was up-regulated： （TGF-β1：260.21 ± 31.01 pg/mL vs 375.49 ± 57.47 pg/mL; TNF-α： 193.40±15.18 pg/mL vs 260.04 ± 37.70 pg/mL; IL-α：339.87 ± 72.95 pg/mL vs 606.47 ± 130.73 pg/mL; IL-10：506.22 ± 112.07 pg/mL vs 316.95 ± 62.74 pg/mL, P 〈 0.01）. CONCLUSION： Baicalin shows certain therapeutic effects on hepatic fibrosis, probably by immunoregulating the imbalance between profibrotic and antifibrotic cytokines.

An experimental study of extracellular signal-regulated kinase and its interventional treatments in hepatic fibrosis

BACKGROUND: The pathogenesis of hepatic fibrosis and cirrhosis is still not fully understood. The extracellular signal-regulated kinase (ERK) pathway is involved in the regulation of cell proliferation and differentiation. The aim of this study was to investigate the effects of PD98059, a specific inhibitor of ERK, on the cell cycle, cell proliferation, secretion of type I collagen and expression of cyclin D1 mRNA, CDK4 mRNA and transforming growth factor-beta 1 (TGF-beta 1) mRNA in rat hepatic stellate cells (HSCs) stimulated by acetaldehyde. METHODS: Rat HSCs stimulated by acetaldehyde were incubated with PD98059 at different concentrations. The cell cycle was analysed by flow cytometry. Cell proliferation was assessed by the methyl thiazolyl tetrazolium colorimetric assay. The mRNA expression of cyclin D1, CDK4 and TGF-beta 1 was examined using the reverse transcriptase-polymerase chain reaction. Type I collagen in the culture medium was detected by enzyme-linked immunosorbent assay. RESULTS: 20, 50 and 100 mu mol/L PD98059 significantly inhibited the proliferation and provoked a G0/G1-phase arrest of acetaldehyde-induced HSCs in a dose-dependent manner. The secretion of type I collagen and the expression of cyclin D1, CDK4 and TGF-beta 1 mRNA in acetaldehyde-induced HSCs were markedly inhibited by 50 and 100 mu mol/L PD98059, respectively. CONCLUSIONS: The ERK pathway regulates the cell proliferation, secretion of type I collagen and the expression of TGF-beta 1 mRNA in rat HSCs stimulated by acetaldehyde, which is likely related to its regulative effect on the cell cycle.

Effects of interferon-alpha on expression of hepatic stellate cell and transforming growth factor-pi and a-smooth muscle actin in rats with hepatic fibrosis

AIM:To investigate the effect of interferon-a (IFN-α) on preventing or reversing hepatic fibrosis in rat experimental model induced by CCI4. METHODS: One hundred and ten Sprague-Dawley rats were divided into five groups: group A (normal controls, n = 18), group B (fibrotic model controls, n = 22), group C (IFN-α prevention, n = 22) initially treated with intramuscular injection of IFN-a in saline daily at the doses of 1× 105 U for 6 wk, group D (IFN-a treatment, n = 24) treated with intra-muscular injection of IFN-a in saline daily at the doses of 1×105 U for 6 wk after the first 6 wk, group E (0.9% sodium chloride treatment control, n = 24) treated with intra-muscular injection of 0.01 mL/kg daily for 6 wk after the first 6 wk. At the end of the experiment, all rats of each group were killed. Samples of the liver obtained by biopsy were subjected to histological, immunohistochemical and electron microscopic studies for the expressions of transforming growth factor-pi (TGF- μ41) and α-smooth muscle actin (α-SMA). RESULTS: The expressions of TGF-pl, the number of activated hepatic stellate cells and a-SMA in hepatic tissue of group C were significantly less than those of group B (P<0.01). The degree of fibrosis score in group B was also significantly less than that of group C under light microscope (P<0.01). CONCLUSION: IFN-a can inhibit the production of TGF-pl, decrease HSC activation and stimulate its apoptosis.

Expression of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic stellate cells during rat hepatic fibrosis and its intervention by IL-10

AIM: To investigate the expression of matrix metallopr-oteinase-2 and tissue inhibitor of metalloproteinase-1 in hepatic fibrosis and the antifibrogenic role of exogenous interleukin-10 (IL-10). METHODS: Hepatic fibrosis was induced by CCI4 administration and 60 male Sprague-Dawley rats were randomly divided into normal control group (group N, 8 rats), CCI4-induced group (group C, 28 rats) and IL-10-treated group (group I, 24 rats). At the beginning of the 7th and 11th wk, rats in each group were routinely perfused with pronase E and type IV collagenase through portal vein catheter and the suspension was centrifuged by 11% Nycodenz density gradient to isolate hepatic stellate cells (HSCs). RT-PCR was used to analyze mRNA of MMP-2 and TIMP-1 from freshly isolated cells. Densitometric data were standardized with β-actin signals. Immunocytochemistry was performed to detect MMP-2 and TIMP-1 expression in HSC cultured for 72 h. RESULTS: Compared to group N in the 7th wk, MMP-2 and TIMP-1 mRNA increased in group C (P= 0.001/0.001) and group I (P= 0.001/0.009). The level of MMP-2 and TIMP-1 mRNA in group I was significantly lower than that in group C (P= 0.001/0.001). In the 11th wk, MMP-2 mRNA in group I was still lower than that in group C (P = 0.005), but both dropped compared with that in the 7th week (P = 0.001/0.004). TIMP-1 mRNA in group I was still lower than that in group C (P= 0.001), and increased in group C (P= 0.001) while decreased in group I (P = 0.042) compared with that in the 7th wk. Same results were found by immunocytochemistry. CONCLUSION: Expression of MMP-2 and TIMP-1 is increased in hepatic fibrosis. IL-10 exhibits an antifibrogenic effect by suppressing MMP-2 and TIMP-1 expression.

Oxymatrine liposome attenuates hepatic fibrosis via targeting hepatic stellate cells

AIM： To investigate the potential mechanism of Arg- Gly-Asp （RGD） peptide-labeled liposome loading oxy- matrine （OM） therapy in CCI4-induced hepatic fibrosis in rats. METHODS： We constructed a rat model of CCh- induced hepatic fibrosis and treated the rats with dif- ferent formulations of OM. To evaluate the antifibrotic effect of OM, we detected levels of alkaline phospha- tase, hepatic histopathology （hematoxylin and eosin stain and Masson staining） and fibrosis-related gene expression of matrix metallopeptidase （MMP）-2, tis- sue inhibitor of metalloproteinase （TIMP）-I as well as type I procollagen via quantitative real-time poly- merase chain reaction. To detect cell viability and apop- tosis of hepatic stellate cells （HSCs）, we performed 3-（4,5）-dimethylthiahiazo（-z-yl）-3,5-diphenytetrazoli- umromide assay and flow cytometry. To reinforce the combination of oxymatrine with HSCs, we constructed fluorescein-isothiocyanate-conjugated Arg-Gly-Asp peptide-labeled liposomes loading OM, and its targeting of HSCs was examined by fluorescent microscopy. RESULTS： OM attenuated CCh-induced hepatic fibro- sis, as defined by reducing serum alkaline phosphatase （344.47± 27.52 U/L vs 550.69 ± 43.78 U/L, P 〈 0.05）, attenuating liver injury and improving collagen deposits （2.36% ± 0.09% vs 7.70% ±0.60%, P 〈 0.05） and downregulating fibrosis-related gene expression, that is, MMP-2, TIMP-1 and type I procollagen （P 〈 0.05）. OM inhibited cell viability and induced apoptosis of HSCs in vitro. RGD promoted OM targeting of HSCs and en- hanced the therapeutic effect of OM in terms of serum alkaline phosphatase （272.51 ± 19.55 U/L vs 344.47 ± 27.52 U/L, P 〈 0.05）, liver injury, collagen deposits （0.26%± 0.09% vs 2.36% ± 0.09%, P 〈 0.05） and downregulating fibrosis-related gene expression, that is, MMP-2, TIMP-1 and type I procollagen （P 〈 0.05）. Moreover, in vitro assay demonstrated that RGD en- hanced the effect of OM on HSC viability and apoptosis. CONCLUSION： OM attenuated hepatic fibrosis by in- hibiting viability and inducing apoptosis of HSCs. The RGD-labeled formulation enhanced the targeting effi- ciency for HSCs and the therapeutic effect.

Adeno-associated virus mediated interferon-gamma inhibits the progression of hepatic fibrosis in vitro and in vivo

AIM:To investigate the effects of adeno-associated virus (AAV) mediated expression of human interferon-γ for gene therapy in experimental hepatic fibrosis in vitro and in vivo. METHODS: We constructed the recombinant AAV encoding human INF-γ (rAAV- INF-γ) and took the primary rat hepatic stellate cells and carbon tetrachloride induced rats as the experimental hepatic fibrosis model in vitro and in vivo. Immunocytochemistry analysis was used to reveal the expression of α-SMA, the marker protein expressed in hepatic stellate cells. The mRNA expression of TGF-β, TIMP-1, and MMP-13 were analyzed by RT-PCR method. In vivo study, the hydroxyproline content in liver and serum AST, ALT were also detected. RESULTS: In vitro study, AAV vector could mediated efficient expression of human INF-γ, which inhibit the activation of hepatic stellate cells, decrease the expression of α-SMA and mRNA of TIMP-1, TGF-β, with the MMP-13 unchanged. In vivo study, the histological examination revealed that rAAV- INF-γ could inhibit the progression of the hepatic fibrosis. In the rAAV-INF-γ induced group, the hydroxyproline content and serum AST, ALT level were decreased to 177±28 μg/g wet liver, 668.5±140.0, 458.4±123.5 U/L, compare with the fibrosis control group 236±31 μg/g wet liver, 1 019.1±276.3, 770.5±154.3 U/L, respectively (P<0.01). mRNA expression of TIMP-1 in the rAAV-INF-γ induced rat liver was decreased while no significant change was observed in TGF-β and MMP-13. CONCLUSION: All these results indicated that rAAV-INF-γ has potential effects for gene therapy of hepatic fibrosis, which could inhibit the progression of hepatic fibrosis.

Effect of IL-10 on the expression of HSC growth factors in hepatic fibrosis rat

AIM： To study the effect of IL-10 on the expression of growth factors - transforming growth factor-β1 （TGF-β1）, epidermal growth factor （EGF）, hepatocyte growth factor （HGF）and platelet-derived growth factor （PDGF） of hepatic stellate cells （HSCs） of hepatic fibrosis rat and the anti-fibrogenic role of exogenous IL-10. METHODS： Hepatic fibrosis was induced by CCI4 administration intra-peritoneally. Sixty clean male Sprague-Dawley （SD） rats were randomly divided into three groups： normal control group （GN, 8 rats）, hepatic fibrosis model group （GC, 28 rats） and IL-10 treated group （GI, 24 rats）. At the beginning of the 7^th and 11^th wk, rats in each group were routinely perfused with pronase E and type IV collagenase through a portal vein catheter and the suspension obtained from the liver was spun by centrifugation with 11% Nycodenz density gradient to isolate HSCs. Histological examination was used to determine the degree of hepatic fibrosis. RT-PCR was employed to analyze mRNA expression from freshly isolated cells. Immunocytochemistry was performed to detect protein expression in primary cultured HSCs. RESULTS： Rat hepatic fibrosis was developed with the increase of injection frequency of CCl4, and HSCs were successfully isolated. At the 7^th and 11^th wk, TGF-β1, EGF, and HGF mRNA in GC increased obviously compared with GN （P = 0.001/0.042, 0.001/0.001, 0.001/0.001） and GI （P= 0.001/0.007, 0.002/0.001, 0.001/0.001）. For TGF-β1, no difference was observed between GI and GN. For EGF, mRNA level in GI increased compared with GN during the 7^th wk （P= 0.005） and 11^th wk （P= 0.049）. For HGF, mRNA level in GI decreased compared with GN at the 7^th wk （P = 0.001） and 11^th wk （P= 0.021）. Between these two time points, TGF-β1 expression at the 7^th wk was higher than that of the 11^th wk （P = 0.049）, but for EGF, the former was lower than the latter （P = 0.022）. As for PDGF mRNA, there was no significant difference between thesegroups, but difference seemed to exist in protein levels. Results by immunocytochemistry of TGF-β1 and EGF were paralleled with the above findings. CONCLUSION： The expression of TGF-β1, EGF and HGF increased in HSC of hepatic fibrosis rat and decreased after treatment with IL-10. IL-10 plays an anti-fibrogenic role by suppressing growth factors expression.

Pathological mechanisms of alcohol-induced hepatic portal hypertension in early stage fibrosis rat model

AIM： To study the role of hepatic sinusoidal capillarization and perisinusoidal fibrosis in rats with alcohol-induced portal hypertension and to discuss the pathological mechanisms of alcohol-induced hepatic portal hypertension. METHODS： Fifty SD rats were divided into control group （n=20） and model group （n=30）. Alcoholic liver fibrosis rat model was induced by intragastric infusion of a mixture containing alcohol, corn oil and pyrazole （1 000：250：3）. Fifteen rats in each group were killed at wk 16. The diameter and pressure of portal vein were measured. Plasma hyaluronic acid （HA）, type IV collagen （COW） and laminin （LN） were determined by radioimmunoassay. Liver tissue was fixed in formalin （10%） and 6-μm thick sections were routinely stained with Mallory and Sirius Red. Liver tissue was treated with rabbit polydonal antibody against LN and ColⅣ. Hepatic non-parenchymal cells were isolated, total protein was extracted and separated by SDS-PAGE. MMP-2 and TIMP-1 protein expression was estimated by Western blotting. RESULTS： The diameter （2.207 ± 0.096 vs 1.528±0.054 mm, P〈0.01） and pressure （11.014±0.395 vs 8.533±0.274 mmHg, P〈0.01） of portal vein were significantly higher in model group than those in the control group. Plasma HA （129.97±16.10 vs 73.09±2.38 ng/mL, P〈0.01）, ColⅣ （210.49±4.36 vs 89.65±4.42 ng/mL, P〈0.01） and LN （105.00±7.29 vs 55.70±4.32 ng/mL, P〈0.01） were upregulated in model group. Abundant collagen deposited around the central vein of Iobules, hepatic sinusoids and hepatocytes in model group. ColⅠ and ColⅢ increased remarkably and perisinusoids were almost surrounded by ColⅢ. Immunohistochemical staining showed that ColⅣ protein level （0.130±0.007 vs 0.032±0.004, P〈0.01） and LN protein level （0.152±0.005 vs 0.029±0.005, P〈0.01） were up-regulated remarkably in model group. MMP-2 protein expression （2.306±1.089 vs 0.612±0.081, P〈0.01） and TIMP-1 protein expression （3.015±1.364 vs 0.446±0.009, P〈0.01） in freshly isolated hepatic nonparenchymal cells were up-regulated in model group and TIMP-1 protein expression was evidently higher than MMP-2 protein expression （2.669±0.170 vs 1.695±0.008, P〈0.05）. CONCLUSION： Hepatic sinusoidal capillarization and peri-sinusoidal fibrosis are responsible for alcoholinduced portal hypertension in rats,

Regression of hepatic fibrosis after pharmacological therapy for nonalcoholic steatohepatitis

The global incidence of nonalcoholic fatty liver disease(NAFLD)is escalating considerably.NAFLD covers a range of liver conditions from simple steatosis to the more severe form known as nonalcoholic steatohepatitis,which involves chronic liver inflammation and the transformation of hepatic stellate cells into myofibroblasts that generate excess extracellular matrix,leading to fibrosis.Hepatocyte ballooning is a key catalyst for fibrosis progression,potentially advancing to cirrhosis and its decompensated state.Fibrosis is a critical prognostic factor for outcomes in patients with NAFLD;therefore,those with substantial fibrosis require timely intervention.Although liver biopsy is the most reliable method for fibrosis detection,it is associated with certain risks and limitations,particularly in routine screening.Consequently,various noninvasive diagnostic techniques have been introduced.This review examines the increasing prevalence of NAFLD,evaluates the noninvasive diagnostic techniques for fibrosis,and assesses their efficacy in staging the disease.In addition,it critically appraises current and emerging antifibrotic therapies,focusing on their mechanisms,efficacy,and potential in reversing fibrosis.This review underscores the urgent need for effective therapeutic strategies,given the dire consequences of advanced fibrosis.

New role and molecular mechanism of Gadd45a in hepatic fibrosis

AIM: To investigate the role of Gadd45a in hepatic fibrosis and the transforming growth factor (TGF)-beta/ Smad signaling pathway. METHODS: Wild-type male BALB/c mice were treated with CCl4 to induce a model of chronic liver injury. Hepatic stellate cells (HSCs) were isolated from the liver of BALB/c mice and were treated with small interfering RNAs (siRNAs) targeting Gadd45a or the pcDNA3.1-Gadd45a recombinant plasmid. Cellular alpha-smooth muscle actin (alpha-SMA), beta-actin, type I collagen, phospho-Smad2, phospho-Smad3, Smad2, Smad3, and Smad4 were detected by Western blots. The mRNA levels of alpha-SMA, beta-actin, and type I collagen were determined by quantitative real-time (qRT)-PCR analyses. Reactive oxygen species production was monitored by flow cytometry using 2,7-dichlorodihydrofluorescein diacetate. Gadd45a, Gadd45b, anti-Gadd45g, type I collagen, and SMA local expression in liver tissue were measured by histologic and immunohistochemical analyses. RESULTS: Significant downregulation of Gadd45a, but not Gadd45b or Gadd45g, accompanied by activation of the TGF-beta/Smad signaling pathways was detected in fibrotic liver tissues of mice and isolated HSCs with chronic liver injury induced by CCl4 treatment. Overexpression of Gadd45a reduced the expression of extracellular matrix proteins and alpha-SMA in HSCs, whereas transient knockdown of Gadd45a with siRNA reversed this process. Gadd45a inhibited the activity of a plasminogen activator inhibitor-1 promoter construct and (CAGA)(9) MLP-Luc, an artificial Smad3/4-specific reporter, as well as reduced the phosphorylation and nuclear translocation of Smad3. Gadd45a showed protective effects by scavenging reactive oxygen species and upregulating antioxidant enzymes. CONCLUSION: Gadd45a may counteract hepatic fibrosis by regulating the activation of HSCs via the inhibition of TGF-beta/Smad signaling.