Sja-let-7 suppresses the development of liver fibrosis via Schistosoma japonicum extracellular vesicles.

Schistosomiasis is a fatal zoonotic parasitic disease that also threatens human health. The main pathological features of schistosomiasis are granulomatous inflammation and subsequent liver fibrosis, which is a complex, chronic, and progressive disease. Extracellular vesicles (EVs) derived from schistosome eggs are broadly involved in host-parasite communication and act as important contributors to schistosome-induced liver fibrosis. However, it remains unclear whether substances secreted by the EVs of Schistosoma japonicum, a long-term parasitic "partner" in the hepatic portal vein of the host, also participate in liver fibrosis. Here, we report that EVs derived from S. japonicum worms attenuated liver fibrosis by delivering sja-let-7 into hepatic stellate cells (HSCs). Mechanistically, activation of HSCs was reduced by targeting collagen type I alpha 2 chain (Col1α2) and downregulation of the TGF-ß/Smad signaling pathway both in vivo and in vitro. Overall, these results contribute to further understanding of the molecular mechanisms underlying host-parasite interactions and identified the sja-let-7/Col1α2/TGF-ß/Smad axis as a potential target for treatment of schistosomiasis-related liver fibrosis.

An improved experimental method for simultaneously isolating hepatocytes and hepatic stellate cells in mouse liver infected with Echinococcus multilocularis.

BACKGROUND: Alveolar echinococcosis (AE) is a zoonotic disease caused by the larval stage of Echinococcus multilocularis parasitizing in the human liver, causing local pathological changes in the liver and manifesting as hyperplasia, liver fibrosis, atrophy, degeneration, and necrosis. Here, we report a method that can simultaneously isolate hepatocytes and hepatic stellate cells (HSCs) from mice infected with Echinococcus multilocularis. METHODS: A mouse model of AE was established. Hepatocytes and HSCs were isolated from mouse liver using a two-step method combining in situ collagenase perfusion and gradient centrifugation. Expressions of Alb, Desmin, and α-SMA were detected with immunofluorescence to identify the isolated hepatocytes and HSCs. RESULTS: The viability and purity of hepatocytes and HSCs both reached 90% or above. For hepatocytes, clear cell boundaries were observed, and the nuclei were round or oval, with clear nucleoli. There was a homogeneous distribution of the hepatocyte marker Alb in the cytoplasm of hepatocytes. Lipid droplets and Desmin expression were observed in the cytoplasm of freshly isolated HSCs. During the activation of HSCs, the lipid droplets gradually decreased and disappeared with a high expression of α-SMA. CONCLUSION: Hepatocytes and HSCs are simultaneously isolated. This may provide a research tool to investigate the interaction between hepatocytes and HSCs and to investigate the mechanism of Echinococcus multilocularis infection-induced liver pathological changes.

A schistosome miRNA promotes host hepatic fibrosis by targeting transforming growth factor beta receptor III.

BACKGROUND & AIMS: MicroRNAs (MiRNAs) derived from parasites, and even from plants, have been detected in body fluids and are known to modulate host genes. In this study, we aimed to investigate if the schistosome miRNAs are involved in the occurrence and progression of hepatic fibrosis during Schistosoma japonicum (S. japonicum) infection. METHODS: The presence of miRNAs from S. japonicum (sja-miRNAs) in hepatic stellate cells (HSCs) was detected by RNA sequencing. sja-miRNAs were screened by transfecting HSCs with sja-miRNA mimics. The role of sja-miR-2162 in hepatic fibrosis was evaluated by either elevating its expression in naïve mice or by inhibiting its activity in infected mice, through administration of recombinant adeno-associated virus serotype 8 vectors expressing sja-miR-2162 or miRNA sponges, respectively. RESULTS: We identified a miRNA of S. japonicum, sja-miR-2162, that was consistently present in the HSCs of infected mice. Transfection of sja-miR-2162 mimics led to activation of HSC cells in vitro, characterized by elevation of collagens and α-SMA. The rAAV8-mediated delivery of sja-miR-2162 to naïve mice induced hepatic fibrosis, while sustained inhibition of sja-miR-2162 in infected mice attenuated hepatic fibrosis. The transforming growth factor beta receptor III (TGFBR3), a negative regulator of TGF-ß signaling, was a direct target of sja-miR-2162 in HSCs. CONCLUSIONS: This study demonstrated that pathogen-derived miRNAs directly promote hepatic fibrogenesis in a cross-species manner, and their efficient and sustained inhibition might present a promising therapeutic intervention for infectious diseases. LAY SUMMARY: A schistosome-specific microRNA, sja-miR-2162, is consistently present in the hepatic stellate cells of mice infected with S. japonicum, where it promotes hepatic fibrosis in the host through cross-species regulation of host fibrosis-related genes. The efficient and sustained inhibition of pathogen-derived micRNAs may represent a novel therapeutic intervention for infectious diseases.

Down-regulation of microRNA-203-3p initiates type 2 pathology during schistosome infection via elevation of interleukin-33.

The type 2 immune response is the central mechanism of disease progression in schistosomiasis, but the signals that induce it after infection remain elusive. Aberrant microRNA (miRNA) expression is a hallmark of human diseases including schistosomiasis, and targeting the deregulated miRNA can mitigate disease outcomes. Here, we demonstrate that efficient and sustained elevation of miR-203-3p in liver tissues, using the highly hepatotropic recombinant adeno-associated virus serotype 8 (rAAV8), protects mice against lethal schistosome infection by alleviating hepatic fibrosis. We show that miR-203-3p targets interleukin-33 (IL-33), an inducer of type 2 immunity, in hepatic stellate cells to regulate the expansion and IL-13 production of hepatic group 2 innate lymphoid cells during infection. Our study highlights the potential of rAAV8-mediated miR-203-3p elevation as a therapeutic intervention for fibrotic diseases.

rSjP40 suppresses hepatic stellate cell activation by promoting microRNA-155 expression and inhibiting STAT5 and FOXO3a expression.

Activation of hepatic stellate cells (HSCs) is the central event of the evolution of hepatic fibrosis. Schistosomiasis is one of the pathogenic factors which could induce hepatic fibrosis. Previous studies have shown that recombinant Schistosoma japonicum egg antigen P40 (rSjP40) can inhibit the activation and proliferation of HSCs. MicroRNA-155 is one of the multifunctional noncoding RNA, which is involved in a series of important biological processes including cell development, proliferation, differentiation and apoptosis. Here, we try to observe the role of microRNA-155 in rSjP40-inhibited HSC activation and explore its potential mechanisms. We found that microRNA-155 was raised in rSjP40-treated HSCs, and further studies have shown that rSjP40 enhanced microRNA-155 expression by inhibiting STAT5 transcription. Up-regulated microRNA-155 can down-regulate the expression of FOXO3a and then participate in rSjP40-inhibited expression of α-smooth muscle actin (α-SMA) and collagen I. Furthermore, we observed microRNA-155 inhibitor could partially restore the down-regulation of FOXO3a, α-SMA and collagen I expression in LX-2 cells induced by rSjP40. Therefore, our research provides further insight into the mechanism by which rSjP40 could inhibit HSC activation via miR-155.

Antischistosomiasis Liver Fibrosis Effects of Chlorogenic Acid through IL-13/miR-21/Smad7 Signaling Interactions In Vivo and In Vitro.

This study investigated the antischistosomiasis liver fibrosis effects of chlorogenic acid (CGA) on interleukin 13 (IL-13)/microRNA-21 (miR-21)/Smad7 signaling interactions in the hepatic stellate LX2 cell line and schistosome-infected mice. The transfection was based on the ability of the GV273-miR-21-enhanced green fluorescent protein (EGFP) and GV369-miR-21-EGFP lentiviral system to up- or downregulate the miR-21 gene in LX2 cells. The mRNA expression of miR-21, Smad7, and connective tissue growth factor (CTGF) and the protein expression of Smad7, CTGF, Smad1, phosphor-Smad1 (p-Smad1), Smad2, p-Smad2, Smad2/3, p-Smad2/3, transforming growth factor ß (TGF-ß) receptor I, and α-smooth muscle actin (α-SMA) was assayed. Pathological manifestation of hepatic tissue was assessed for the degree of liver fibrosis in animals. The results showed that CGA could inhibit the mRNA expression of miR-21, promote Smad7, and inhibit CTGF mRNA expression. Meanwhile, CGA could significantly lower the protein levels of CTGF, p-Smad1, p-Smad2, p-Smad2/3, TGF-ß receptor I, and α-SMA and elevate the Smad7 protein level. In vivo, with treatment with CGA, the signaling molecules of IL-13/miR-21/Smad7 interactions were markedly regulated. CGA could also reduce the degree of liver fibrosis in pathological manifestations. In conclusion, CGA could inhibit schistosomiasis-induced hepatic fibrosis through IL-13/miR-21/Smad7 signaling interactions in LX2 cells and schistosome-infected mice and might serve as an antifibrosis agent for treating schistosomiasis liver fibrosis.

Artichoke leaf extract protects liver of Schistosoma mansoni infected mice through modulation of hepatic stellate cells recruitment.

Schistosomiasis is the second most common human parasitic disease worldwide. It is responsible for 300000 deaths per year. Liver fibrosis is the main pathology of schistosomiasis and its complications are the major cause of death in infected cases. Unfortunately, the therapeutic dose of praziquantel (PZQ) - the main drug treatment - doesn't markedly affect fibrosis. In the present study, antiparasitic and hepatoprotective properties of artichoke leaf extract (ALE) were tested on mice experimentally infected with Schistosoma mansoni (S. mansoni) and were compared to PZQ. Four mice groups were infected with S. mansoni. The first three groups received ALE, ALE + PZQ and PZQ respectively. The 4th was the positive control and the 5th was the negative control group. Worm load, egg count, granuloma numbers and diameters were measured to assess ALE anti-schistoaomal properties. Masson's trichrome staining of fibrosis, immune staining of hepatic stellate cells (HSCs) and estimation of liver enzymes were done to assess its hepato-protective action. Although it had no significant effects on worm or tissue egg load and granuloma number, ALE caused significant reduction of granuloma diameter, improvement of liver functions and liver fibrosis. ALE caused statistically significant changes in HSCs distribution. It reduced granuloma size by increasing HSCs recruitment inside granuloma and limited liver fibrosis by their inhibition in the peri- and inter-granuloma liver tissue. It was concluded that despite failure of ALE to treat S. mansoni infection, it can limit liver damage caused by this parasite by modulating HSCs recruitment.

Schistosoma japonicum protein SjP40 inhibits TGF-ß1-induced activation of hepatic stellate cells.

SjP40 is a major egg antigen of Schistosoma japonicum. In the present study, the authors investigated the effect of SjP40 in vitro on transforming growth factor-ß1 (TGF-ß1)- stimulated hepatic stellate cells (HSCs). LX-2, an immortalized human HSC line, was treated with purified recombinant SjP40 (rSjP40) in the presence or absence of TGF-ß1. Quantitative real-time polymerase chain reaction and western blot analysis were performed to determine messenger ribonucleic acid and protein of fibrogenic genes and TGF-ß signaling pathway. The results showed that expression of fibrogenic genes was significantly reduced by rSjP40. Furthermore, rSjP40 also suppressed the TGF-ß1-induced upregulation of Smads and ERK proteins. We also found that the effect of rSjP40 on HSCs was similar to SB431542, an inhibitor of type I TGF-ß receptor. In conclusion, the data suggest that SjP40 attenuates HSC activation, which might be, at least in part, mediated by inhibiting the TGF-ß and ERK signaling pathways.

CD34(+) cell therapy is safe and effective in slowing the decline of hepatic reserve function in patients with decompensated liver cirrhosis.

BACKGROUND AND AIM: Preclinical studies in rodent models of chronic liver fibrosis have shown that transplantation of peripheral blood (PB) CD34(+) cells leads to hepatic regeneration and a reduction of liver fibrosis by suppressing hepatic stellate cell activity and increasing matrix metalloproteinase activity. The aim of this study was to examine the safety and clinical efficacy of intrahepatic transplantation of autologous granulocyte colony-stimulating factor (G-CSF)-mobilized PB-CD34(+) cells in patients with decompensated liver cirrhosis. METHODS: PB-CD34(+) cells were isolated from G-CSF-mobilized apheresis products. Ten patients were treated with G-CSF-mobilized PB-CD34(+) cells (treatment group) and seven patients were treated with standard medical therapy. For mobilization, patients in the treatment group received subcutaneous injections of 10 µg G-CSF/kg/day for 5 days. The cells were then injected at three different doses (5 × 10(5) , 1 × 10(6) and 2 × 10(6) cells/kg) through the hepatic artery. Thereafter, all patients were followed up for 24 months. RESULTS: G-CSF treatment and leukapheresis were well tolerated, and no serious adverse events were observed. Patients in the treatment group had a significant but transient splenomegaly. After 24 weeks, serum albumin was significantly increased in patients who had received middle or high doses of CD34(+) cells compared with baseline. Doppler ultrasound showed a significant increase in hepatic blood flow velocity and blood flow volume after CD34(+) cell therapy. The hepatic vein pressure gradient decreased in two patients who received high-dose CD34(+) cells at week 16. CONCLUSIONS: CD34(+) cell therapy is feasible, safe and effective in slowing the decline of hepatic reserve function.

Proteomic identification of potential Clonorchis sinensis excretory/secretory products capable of binding and activating human hepatic stellate cells.

Epidemiological and experimental evidence demonstrated that Clonorchis sinensis is an important risk factor of hepatic fibrosis and cholangiocarcinoma. C. sinensis excretory/secretory products (CsESPs) are protein complex including proteases, antioxidant enzymes, and metabolic enzymes, which may contribute to pathogenesis of liver fluke-associated hepatobiliary diseases. However, potential CsESP candidates involved into hepatic fibrosis and cholangiocarcinoma still remain to be elucidated. In the present study, we performed proteomic identification of CsESP candidates capable of binding and activating human hepatic stellate cell line LX-2. Immunofluorescence analysis confirmed the interaction of CsESPs with LX-2 cell membrane. LX-2 cells could be stimulated by CsESPs from 24 h post incubation (p < 0.05). Specifically, 50 µg/ml of CsESPs showed the strongest effect on cell proliferation in methyl thiazolyl tetrazolium (MTT) assay which could also be demonstrated by flow cytometry analysis (p < 0.01). Furthermore, expression level of human type III collagen in LX-2 cells treated with CsESPs was significantly higher than that in control cells measured by molecular beacon and semiquantitative reverse transcription (RT)-PCR approaches (p < 0.01). Finally, CsESPs before and after incubation with LX-2 cells were subjected to two-dimensional gel electrophoresis (2-DE) analysis and matrix associated laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis. Nine proteins with abundance change above threefold were Rho GTPase-activating protein, mitochondrial cytochrome c oxidase subunit Va, α-enolase, phospholipase C, interleukin-15, insect-derived growth factor, cytochrome c oxidase subunit VI, DNAH1 protein, and kinesin light chain. Taken together, we identified potential CsESP candidates capable of binding and activating human hepatic stellate cells, providing more direct evidences that are previously unknown to accelerate strategies for C. sinensis prevention.

Human hepatic stellate cells in primary culture are safe targets for Leishmania donovani.

Leishmania parasites can escape the immune response by invading cell types lacking leishmanicidal mechanisms. Silent persistence of Leishmania parasites in the host organism is responsible for asymptomatic carriage and relapses after cured leishmaniasis. Here, we studied the interaction between Hepatic Stellate Cells (HSC) and Leishmania. An original model of human HSC in primary culture infected with L. donovani was developed. The presence of intracellular parasites was studied and quantified using optical and confocal microscopy. HSC characteristics were studied using microscopy, methylene blue assay, long-term cultures and qPCR. We showed for the first time that human HSC are permissive to L. donovani infection, with no modification of HSC survival, growth rate and proinflammatory and fibrogenic characteristics. Intracellular parasites did not replicate but HSC had no effect on their survival. Indeed, after a 40-day culture, infected HSC cultures transferred on NNN medium yielded new promastigotes that were able to proliferate and efficiently infect new cells. HSC are permissive to L. donovani, with neither parasite killing nor apparent cell damage. Thus, HSC could act as potent sanctuary cells for Leishmania in the liver, which could partially explain parasite reactivation after an asymptomatic carriage or a cured visceral leishmaniasis.

Structural changes and expression of hepatic fibrosis-related proteins in coculture of Echinococcus multilocularis protoscoleces and human hepatic stellate cells.

BACKGROUND: Echinococcus multilocularis is the causative agent of human hepatic alveolar echinococcosis (AE). AE can cause damage to several organs, primarily the liver, and have severe outcomes, such as hepatic failure and encephalopathy. The main purpose of this study was to explore the interactions between hepatic stellate cells (HSCs) and E. multilocularis protoscoleces (PSCs). The results of this study provide an experimental basis for further examination of the pathogenesis of hepatic fibrosis due to AE infection. METHODS: We investigated the role of Echinococcus multilocularis (Echinococcus genus) PSCs in hepatic fibrosis by examining structural changes and measuring hepatic fibrosis-related protein levels in cocultures of PSCs and human HSCs. Structural changes were detected by transmission electron microscopy (TEM), and levels of the hepatic fibrosis-related proteins collagen I (Col-I), alpha-smooth muscle actin (α-SMA) and osteopontin (OPN) were measured by western blotting and enzyme-linked immunosorbent assay (ELISA). RESULTS: Under coculture (1) both PSCs and HSCs exhibited morphological changes, as observed by TEM; (2) Col-I, α-SMA, and OPN expression levels, which were determined by western blotting and ELISA, significantly increased after 3 days of incubation. CONCLUSIONS: The results of this study provide insights into the molecular mechanisms of AE-induced hepatic fibrosis.

The role of let-7b in the inhibition of hepatic stellate cell activation by rSjP40.

BACKGROUND: Hepatic stellate cells (HSCs) are one of the main cell types involved in liver fibrosis induced by many factors, including schistosomes. Previous studies in our lab have shown that recombinant P40 protein from Schistosoma japonicum (rSjP40) can inhibit HSC activation in vitro. Let-7b is a member of the let-7 microRNA family and plays an inhibitory role in a variety of diseases and inflammatory conditions. In this study, we investigated the role of let-7b in the inhibition of HSC activation by rSjP40. METHODS: Expression of let-7b was detected by quantitative real-time PCR. A dual luciferase assay was used to confirm direct interaction between let-7b and collagen I. We also used western blot to assess protein levels of TGFßRI and collagen type I α1 (COL1A1). RESULTS: We found that rSjP40 up-regulates expression of let-7b in HSCs. Let-7b inhibits collagen I expression by directly targeting the 3'UTR region of the collagen I gene. Furthermore, we discovered that let-7b inhibitor partially restores the loss of collagen I expression caused by rSjP40. CONCLUSION: Our research clarifies the role of let-7b in the inhibition of HSC activation by rSjP40 and will provide new insights and ideas for the inhibition of HSC activation and treatment of liver fibrosis.

JQ-1 ameliorates schistosomiasis liver fibrosis by suppressing JAK2 and STAT3 activation.

Schistosomiasis is a serious parasitic infection caused by Schistosoma. The parasite deposits eggs in the host liver, causing inflammation that activates hepatic stellate cells (HSCs), which leads to liver fibrosis. Currently, there is no effective therapy for liver fibrosis; thus, treatments are urgently needed. Therefore, in the present study, mice infected with Schistosoma japonicum were treated with JQ-1, a small-molecule bromodomain inhibitor with reliable anti-tumor and anti-inflammatory activities. The fibrotic area of the liver measured by computer-assisted morphometric analysis and the expression levels of the cytoskeletal protein alpha smooth muscle actin (α-SMA) and of collagen assessed by quantitative PCR, Western blot and immunohistochemistry were significantly decreased in the liver following JQ-1 treatment compared with vehicle-treated controls. Total RNA was extracted from the liver of JQ-1-treated Schistosoma-infected mice for RNA-sequencing analysis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that JQ-1 affected biological processes and the expression of cellular components known to play key roles in the transdifferentiation of HSCs to myofibroblasts. In vitro treatment with JQ-1 of JS-1 cells, a mouse HSC line, indicated that JQ-1 significantly inhibited JS-1 proliferation but had no effect on JS-1 activity, senescence, or apoptosis. Western blot results showed that JQ-1 inhibited the expression levels of phosphorylated JAK2 and phosphorylated STAT3 without altering expression levels of these non-phosphorylated proteins. Taken together, these findings suggested that JQ-1 treatment ameliorated S. japonicum egg-induced liver fibrosis, at least in part, by suppressing HSC activation and proliferation through the inhibition of JAK2/STAT3 signaling. These results lay a foundation for the development of novel approaches to treat and control liver fibrosis caused by S. japonicum.

MiR-130a-3p Alleviates Liver Fibrosis by Suppressing HSCs Activation and Skewing Macrophage to Ly6Clo Phenotype.

Emerging evidences have highlighted the crucial role of microRNAs (miRNAs) in the liver cirrhosis, but the relationship between miR-130a-3p and liver cirrhosis is not entirely clear. As we all know, schistosomiasis, as one of the zoonoses, can lead to liver cirrhosis when it advances. In this study, we investigated the biological functions of miR-130a-3p on the liver fibrosis of schistosomiasis in vivo and in vitro. The mice infected with Schistosoma japonicum (S. japonicum) were treated with lentivirus vector (LV)-miR-130a-3p by hydrodynamic injection through the tail vein. Our findings showed significantly decreased expression of miR-130a-3p both in the serum of patients with cirrhosis and in the liver of mice infected with S. japonicum. The results showed that LV-miR-130a-3p could effectively enter into the liver and alleviate liver granulomatous inflammation and collagen deposition. Simultaneously, LV-miR-130a-3p-promoted macrophages presented the Ly6Clo phenotype, concomitant with the decreased expression of the tissue inhibitor of metalloproteinases (TIMP) 1, and increased the expression of matrix metalloproteinase (MMP) 2, which contributed to the dissolution of collagen. Furthermore, overexpression of miR-130a-3p not only inhibited the activation and proliferation of hepatic stellate cells (HSCs) but also induced the apoptosis of HSCs. In addition, we also confirmed that miR-130a-3p enables to bind with mitogen-activated protein kinase (MAPK) 1 and transforming growth factor-beta receptors (TGFBR) 1 and TGFBR2 genes and inhibit the expressions of these genes. Our findings suggested that miR-130a-3p might represent as the potential candidate biomarker and therapeutic target for the prognosis identification and treatment of schistosomiasis liver fibrosis.

Schistosoma mansoni: egg-induced downregulation of hepatic stellate cell activation and fibrogenesis.

Eggs of Schistosoma mansoni trapped in human liver can lead to fibrosis. Since liver fibrosis requires activation of hepatic stellate cells (HSC) from a quiescent to a myofibroblastic phenotype, we investigated the effects of S. mansoni eggs on this process using in vitro co-cultures with human HSC and evaluated established biomarkers for activation and fibrosis. HSC demonstrate significantly reduced expression of alpha-smooth muscle actin (p<0.001), connective tissue growth factor (p<0.01) and type I collagen (p<0.001) but significantly increased expression of peroxisome proliferator-activated receptor-gamma (p<0.01). Morphologically, HSC exhibited elongated fine cellular processes and reduced size, increased accumulation of lipid droplets and reduced expression and organization of alpha-smooth muscle actin and F-actin stress fibres. Additionally, schistosome eggs prevented the HSC fibrogenic response to exogenous transforming growth factor-beta. In summary, schistosome eggs blocked fibrogenesis in HSC, a finding which may have implications for our understanding of the fibrotic pathology in S. mansoni infections.

rSjp40 inhibits activated hepatic stellate cells by promoting nuclear translocation of YB1 and inducing BMP-7/Smad1/5/8 pathway.

BACKGROUND: Activation of hepatic stellate cells is the dominant pathogenic event during the process of liver fibrosis. Bone morphogenic protein (BMP)-7 has recently been identified as an anti-fibrotic factor and leads to phosphorylation of Smad1/5/8 in activated hepatic stellate cells. Its expression can be upregulated by the transcriptional activator, Y-Box protein-1 (YB1). Previous studies have found that the recombinant Schistosoma japonicum protein p40 (rSjp40) can inhibit the activation of hepatic stellate cells, and based on this evidence we attempted to investigate whether or not BMP-7 is involved in rSjp40's inhibition. METHODS: A human hepatic stellate cell line, the LX-2 cell line, was cultured and treated with rSjp40. The role of BMP-7 was analyzed by Western blot. RESULTS: Our findings testified that knockdown of BMP-7 impaired rSjp40-induced downregulation of α-SMA and phosphorylation of Smad1/5/8 in LX-2 cells. Furthermore, rSjp40 upregulated expression of BMP-7 at both mRNA and protein levels depending on YB1. Interestingly, YB1 was translocated from the cytoplasm to the nucleus upon treatment of rSjp40. CONCLUSIONS: These results suggest that rSjp40 inhibits the activation of hepatic stellate cells by promoting nuclear translocation of YB1 and inducing BMP-7/Smad1/5/8 pathway, which provide a new clue to guide ongoing research into the anti-fibrosis of rSjp40.

Schistosome-Induced Fibrotic Disease: The Role of Hepatic Stellate Cells.

Hepatic fibrosis is a common pathology in various liver diseases. Hepatic stellate cells (HSCs) are the main cell type responsible for collagen deposition and fibrosis formation in the liver. Schistosomiasis is characterised by granulomatous fibrosis around parasite eggs trapped within the liver and other host tissues. This response is facilitated by the recruitment of immune cells and the activation of HSCs. The interactions between HSCs and schistosome eggs are complex and diverse, and a better understanding of these interactions could lead to improved resolution of fibrotic liver disease, including that associated with schistosomiasis. Here, we discuss recent advances in HSC biology and the role of HSCs in hepatic schistosomiasis.

Secreted phospholipase A2 of Clonorchis sinensis activates hepatic stellate cells through a pathway involving JNK signalling.

BACKGROUND: Secreted phospholipase A2 (sPLA2) is a protein secreted by Clonorchis sinensis and is a component of excretory and secretory products (CsESPs). Phospholipase A2 is well known for its role in liver fibrosis and inhibition of tumour cells. The JNK signalling pathway is involved in hepatic stellate cells (HSCs) activation. Blocking JNK activity with SP600125 inhibits HSCs activation. In a previous study, the protein CssPLA2 was expressed in insoluble inclusion bodies. Therefore, it's necessary to express CssPLA2 in water-soluble form and determine whether the enzymatic activity of CssPLA2 or cell signalling pathways is involved in liver fibrosis caused by clonorchiasis. METHODS: Balb/C mice were given an abdominal injection of MBP-CssPLA2. Liver sections with HE and Masson staining were observed to detect accumulation of collagen. Western blot of mouse liver was done to detect the activation of JNK signalling pathway. In vitro, HSCs were incubated with MBP-CssPLA2 to detect the activation of HSCs as well as the activation of JNK signalling pathway. The mutant of MBP-CssPLA2 without enzymatic activity was constructed and was also incubated with HSCs to check whether activation of the HSCs was related to the enzymatic activity of MBP-CssPLA2. RESULTS: The recombinant protein MBP-CssPLA2 was expressed soluble and of good enzymatic activity. A mutant of CssPLA2, without enzymatic activity, was also constructed. In vivo liver sections of Balb/C mice that were given an abdominal injection of 50 µg/ml MBP-CssPLA2 showed an obvious accumulation of collagen and a clear band of P-JNK1 could be seen by western blot of the liver tissue. In vitro, MBP-CssPLA2, as well as the mutant, was incubated with HSCs and it was proved that activation of HSCs was related to activation of the JNK signalling pathway instead of the enzymatic activity of MBP-CssPLA2. CONCLUSIONS: Activation of HSCs by CssPLA2 is related to the activation of the JNK signalling pathway instead of the enzymatic activity of CssPLA2. This finding could provide a promising treatment strategy to interrupt the process of liver fibrosis caused by clonorchiasis.

Activation of NLRP3 inflammasomes in mouse hepatic stellate cells during Schistosoma J. infection.

The major pathological changes during Schistosoma J. infection are characterized by granulomatous inflammation in the liver, a cellular immune response to schistosomal egg antigens. The molecular mechanisms initiating or promoting this schistosomal granulomatous inflammation remain poorly understood. In the present study, we first demonstrated that in mice infected with Schistosoma J. for 6 weeks exhibited increased levels of IL-1ß in liver, a major product of NLRP3 inflammasomes and collagen deposition around the eosinophilic granuloma with Schistosoma J. eggs, which was substantially attenuated by caspase-1 inhibitor, YVAD. This activation of the NLRP3 inflammasome occurred in hepatic stellate cells (HSCs), as shown by a marked increase in co-localization of IL-1ß with HSCs marker, desmin. Using isolated, cultured mouse HSCs, we further explored the mechanisms by which soluble egg antigen (SEA) from Schistosoma J. activates NLRP3 inflammasomes. SEA induced the formation and activation of NLRP3 inflammasomes, which was associated with both redox regulation and lysosomal dysfunction, but not with potassium channel activation. These results suggest that NLRP3 inflammasome activation in HSCs may serve as an early mechanism to turn on the inflammatory response and thereby instigate liver fibrosis during Schistosoma J infection.