Aldehyde dehydrogenase 2 activation ameliorates CCl4‐induced chronic liver fibrosis in mice by up‐regulating Nrf2/HO‐1 antioxidant pathway

Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is critical in the pathogenesis of alcoholic liver cirrhosis. However, the effect of ALHD2 on liver fibrosis remains to be further elucidated. This study aimed to demonstrate whether ALDH2 regulates carbon tetrachloride (CCl₄)‐induced liver fibrosis and to investigate the efficacy of Alda‐1, a specific activator of ALDH2, on attenuating liver fibrosis. ALDH2 expression was increased after chronic CCl₄ exposure. ALDH2 deficiency accentuated CCl₄‐induced liver fibrosis in mice, accompanied by increased expression of collagen 1α1, α‐SMA and TIMP‐1. Moreover, ALDH2 knockout triggered more ROS generation, hepatocyte apoptosis and impaired mitophagy after CCl₄ treatment. In cultured HSC‐T6 cells, ALDH2 knockdown by transfecting with lentivirus vector increased ROS generation and α‐SMA expression in an in vitro hepatocyte fibrosis model using TGF‐β1. ALDH2 overexpression by lentivirus or activation by Alda‐1 administration partly reversed the effect of TGF‐β1, whereas ALDH2 knockdown totally blocked the protective effect of Alda‐1. Furthermore, Alda‐1 administration protected against liver fibrosis in vivo, which might be mediated through up‐regulation of Nrf2/HO‐1 cascade and activation of Parkin‐related mitophagy. These findings indicate that ALDH2 deficiency aggravated CCl₄‐induced hepatic fibrosis through ROS overproduction, increased apoptosis and mitochondrial damage, whereas ALDH2 activation through Alda‐1 administration alleviated hepatic fibrosis partly through activation of the Nrf2/HO‐1 antioxidant pathway and Parkin‐related mitophagy, which indicate ALDH2 as a promising anti‐fibrotic target and Alda‐1 as a potential therapeutic agent in treating CCl₄‐induced liver fibrosis.     

Differential fibrotic phenotypes of hepatic stellate cells within 3D liver organoids

Liver fibrosis occurs in most cases of chronic liver disease, which are somewhat common, but also a potentially deadly group of diseases. In vitro modeling of liver fibrosis relies primarily on the isolation of in vivo activated hepatic stellate cells (aHSCs) and studying them in standard tissue culture dishes (two-dimensional [2D]). In contrast, modeling of fibrosis in a biofabricated three-dimensional (3D) construct allows us to study changes to the environment, such as extracellular matrix (ECM) composition and structure, and tissue rigidity. In the current study, we used aHSCs produced through subcultures in 2D and encapsulated them in a 3D collagen gel to form spherical constructs. In parallel, and as a comparison, we used an established HSC line, LX-2, representing early and less severe fibrosis. Compared with LX-2 cells, the aHSCs created a stiffer environment and expressed higher levels of TIMP1 and LOXL2, all of which are indicative of advanced liver fibrosis. Collectively, this study presents a fibrosis model that could be incorporated with multi-cellular models to more accurately reflect the effects of a severe fibrotic environment on liver function.     

Byakangelicin protects against carbon tetrachloride–induced liver injury and fibrosis in mice

Liver fibrosis is a disease caused by long‐term damage that is related to a number of factors. The current research on the treatment of liver fibrosis mainly focuses on the activation of hepatic stellate cell, in addition to protecting liver cells. byakangelicin has certain anti‐inflammatory ability, but its effect on liver fibrosis is unclear. This study aims to explore whether byakangelicin plays a role in the development of liver fibrosis and to explore its mechanism. We determined that byakangelicin has a certain ability to resist fibrosis and reduce liver cell damage in a model of carbon tetrachloride–induced liver fibrosis in mice. Thereafter, we performed further verification in vitro. The signalling pathways of two important pro‐fibrotic cytokines, transforming growth factor‐β and platelet‐derived growth factor, were studied. Results showed that byakangelicin can inhibit related pathways. According to the hepatoprotective effect of byakangelicin observed in animal experiments, we studied the effect of byakangelicin on 4‐HNE–induced hepatocyte (HepG2) apoptosis and explored its related pathways. The results showed that byakangelicin could attenuate 4‐HNE–induced hepatocyte apoptosis via inhibiting ASK‐1/JNK signalling. In conclusion, byakangelicin could improve carbon tetrachloride–induced liver fibrosis and liver injury by inhibiting hepatic stellate cell proliferation and activation and suppressing hepatocyte apoptosis.     

Exosomes derived from miR‐181‐5p‐modified adipose‐derived mesenchymal stem cells prevent liver fibrosis via autophagy activation

Proliferating hepatic stellate cells (HSCs) respond to liver damage by secreting collagens that form fibrous scar tissue, which can lead to cirrhosis if in appropriately regulated. Advancement of microRNA (miRNA) hepatic therapies has been hampered by difficulties in delivering miRNA to damaged tissue. However, exosomes secreted by adipose‐derived mesenchymal stem cells (ADSCs) can be exploited to deliver miRNAs to HSCs. ADSCs were engineered to overexpress miRNA‐181‐5p (miR‐181‐5p‐ADSCs) to selectively home exosomes to mouse hepatic stellate (HST‐T6) cells or a CCl4‐induced liver fibrosis murine model and compared with non‐targeting control Caenorhabditis elegans miR‐67 (cel‐miR‐67)‐ADSCs. In vitro analysis confirmed that the transfer of miR‐181‐5p from miR‐181‐5p‐ADSCs occurred via secreted exosomal uptake. Exosomes were visualized in HST‐T6 cells using cyc3‐labelled pre‐miRNA‐transfected ADSCs with/without the exosomal inhibitor, GW4869. The effects of miRNA‐181‐5p overexpression on the fibrosis associated STAT3/Bcl‐2/Beclin 1 pathway and components of the extracellular matrix were assessed. Exosomes from miR181‐5p‐ADSCs down‐regulated Stat3 and Bcl‐2 and activated autophagy in the HST‐T6 cells. Furthermore, the up‐regulated expression of fibrotic genes in HST‐T6 cells induced by TGF‐β1 was repressed following the addition of isolated miR181‐5p‐ADSC exosomes compared with miR‐67‐ADSCexosomes. Exosome therapy attenuated liver injury and significantly down‐regulated collagen I, vimentin, α‐SMA and fibronectin in liver, compared with controls. Taken together, the effective anti‐fibrotic function of engineered ADSCs is able to selectively transfer miR‐181‐5p to damaged liver cells and will pave the way for the use of exosome‐ADSCs for therapeutic delivery of miRNA targeting liver disease.     

p38-MAPK- and caspase-3-mediated superoxide-induced apoptosis of rat hepatic stellate cells: reversal by retinoic acid

Reactive oxygen species (ROS) activate retinoid-containing quiescent hepatic stellate cells (qHSCs) to retinoid-deficient fibrogenic myofibroblast-like cells (aHSCs). However, ROS also cause apoptosis of aHSCs, and apoptotic aHSCs are observed in inflammatory fibrotic liver. Here, we investigated mechanisms of the effects of oxidative stress on the survival of qHSCs and aHSCs. HSCs from normal rat liver were used after overnight culture (qHSCs), or in 3-5 passages (aHSCs). For in vivo induction of oxidative stress, tert-butylhydroperoxide was injected into control and CCl4-induced cirrhotic rats. Spontaneous caspase-3 activation and apoptosis, observed in cultured qHSCs, decreased with time and were unaffected by superoxide. In contrast, superoxide caused caspase-3 and p38-MAPK activation, reduction in Bcl-xL expression, and apoptosis in aHSCs. Inhibition of caspase-3 and p38-MAPK did not affect the viability of qHSCs in the absence or presence of superoxide, but inhibited superoxide-induced death of aHSCs. Glutathione (GSH) level and activities of superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) were lower in aHSCs than qHSCs. Superoxide increased GSH content, and activities of SOD, catalase and GPx in qHSCs but not in aHSCs. Incubation of 13-cis-retinoic acid (RA)-treated aHSCs with superoxide increased their GSH content significantly, and prevented superoxide-induced p38-MAPK and caspase-3 activation while dramatically reducing the extent of apoptosis. Finally, oxidative stress induced in vivo caused apoptosis of aHSCs in cirrhotic but not of qHSCs in control rats. These results suggest that the absence of retinoids render aHSCs susceptible to superoxide-induced apoptosis via caspase-3 and p38-MAPK activation.     

Curcumin attenuates angiogenesis in liver fibrosis and inhibits angiogenic properties of hepatic stellate cells

Hepatic fibrosis is concomitant with sinusoidal pathological angiogenesis, which has been highlighted as novel therapeutic targets for the treatment of chronic liver disease. Our prior studies have demonstrated that curcumin has potent antifibrotic activity, but the mechanisms remain to be elucidated. The current work demonstrated that curcumin ameliorated fibrotic injury and sinusoidal angiogenesis in rat liver with fibrosis caused by carbon tetrachloride. Curcumin reduced the expression of a number of angiogenic markers in fibrotic liver. Experiments in vitro showed that the viability and vascularization of rat liver sinusoidal endothelial cells and rat aortic ring angiogenesis were not impaired by curcumin. These results indicated that hepatic stellate cells (HSCs) that are characterized as liver‐specific pericytes could be potential target cells for curcumin. Further investigations showed that curcumin inhibited VEGF expression in HSCs associated with disrupting platelet‐derived growth factor‐β receptor (PDGF‐βR)/ERK and mTOR pathways. HSC motility and vascularization were also suppressed by curcumin associated with blocking PDGF‐βR/focal adhesion kinase/RhoA cascade. Gain‐ or loss‐of‐function analyses revealed that activation of peroxisome proliferator‐activated receptor‐γ (PPAR‐γ) was required for curcumin to inhibit angiogenic properties of HSCs. We concluded that curcumin attenuated sinusoidal angiogenesis in liver fibrosis possibly by targeting HSCs via a PPAR‐γ activation‐dependent mechanism. PPAR‐γ could be a target molecule for reducing pathological angiogenesis during liver fibrosis.     

MiR‐129‐5p inhibits glioma cell progression in vitro and in vivo by targeting TGIF2

This study purposed to explore the correlation between miR‐129‐5p and TGIF2 and their impacts on glioma cell progression. Differentially expressed miRNA was screened through microarray analysis. MiR‐129‐5p expression levels in glioma tissues and cells were measured by qRT‐PCR. CCK‐8 assay, flow cytometer, transwell assay and wound‐healing assay were employed to detect cell proliferation, apoptosis and cycle, invasiveness and migration, respectively. Dual‐luciferase reporting assay was performed to confirm the targeted relationship between miR‐129‐5p and TGIF2. The effects of TGIF2 expression on cell biological functions were also investigated using the indicated methods. Tumour xenograft was applied to explore the impact of miR‐129‐5p on tumorigenesis in vivo. MiR‐129‐5p expression was down‐regulated in both glioma tissues and glioma cells, while TGIF2 expression was aberrantly higher than normal level. Dual‐luciferase reporter assay validated the targeting relation between miR‐129‐5p and TGIF2. Overexpression of miR‐129‐5p or down‐regulation of TGIF2 inhibited the proliferation, invasion and migration capacity of glioma cells U87 and U251, and meanwhile blocked the cell cycle as well as induced cell apoptosis. MiR‐129‐5p overexpression repressed the tumour development in vivo. MiR‐129‐5p and TGIF2 had opposite biological functions in glioma cells. MiR‐129‐5p could inhibit glioma cell progression by targeting TGIF2, shining light for the development of target treatment for glioma.     

Celastrol exerts anti‐inflammatory effect in liver fibrosis via activation of AMPK‐SIRT3 signalling

Celastrol, a pentacyclic tritepene extracted from Tripterygium Wilfordi plant, showing potent liver protection effects on several liver‐related diseases. However, the anti‐inflammatory potential of celastrol in liver fibrosis and the detailed mechanisms remain uncovered. This study was to investigate the anti‐inflammatory effect of celastrol in liver fibrosis and to further reveal mechanisms of celastrol‐induced anti‐inflammatory effects with a focus on AMPK‐SIRT3 signalling. Celastrol showed potent ameliorative effects on liver fibrosis both in activated hepatic stellate cells (HSCs) and in fibrotic liver. Celastrol remarkably suppressed inflammation in vivo and inhibited the secretion of inflammatory factors in vitro. Interestingly, celastrol increased SIRT3 promoter activity and SIRT3 expression both in fibrotic liver and in activated HSCs. Furthermore, SIRT3 silencing evidently ameliorated the anti‐inflammatory potential of celastrol. Besides, we found that celastrol could increase the AMPK phosphorylation. Further investigation showed that SIRT3 siRNA decreased SIRT3 expression but had no obvious effect on phosphorylation of AMPK. In addition, inhibition of AMPK by employing compound C (an AMPK inhibitor) or AMPK1α siRNA significantly suppressed SIRT3 expression, suggesting that AMPK was an up‐stream protein of SIRT3 in liver fibrosis. We further found that depletion of AMPK significantly attenuated the inhibitory effect of celastrol on inflammation. Collectively, celastrol attenuated liver fibrosis mainly through inhibition of inflammation by activating AMPK‐SIRT3 signalling, which makes celastrol be a potential candidate compound in treating or protecting against liver fibrosis.     

Disulfiram combined with copper inhibits metastasis and epithelial–mesenchymal transition in hepatocellular carcinoma through the NF‐κB and TGF‐β pathways

Late‐stage hepatocellular carcinoma (HCC) usually has a low survival rate because of the high risk of metastases and the lack of an effective cure. Disulfiram (DSF) has copper (Cu)‐dependent anticancer properties in vitro and in vivo. The present work aims to explore the anti‐metastasis effects and molecular mechanisms of DSF/Cu on HCC cells both in vitro and in vivo. The results showed that DSF inhibited the proliferation, migration and invasion of HCC cells. Cu improved the anti‐metastatic activity of DSF, while Cu alone had no effect. Furthermore, DSF/Cu inhibited both NF‐κB and TGF‐β signalling, including the nuclear translocation of NF‐κB subunits and the expression of Smad4, leading to down‐regulation of Snail and Slug, which contributed to phenotype epithelial–mesenchymal transition (EMT). Finally, DSF/Cu inhibited the lung metastasis of Hep3B cells not only in a subcutaneous tumour model but also in an orthotopic liver metastasis assay. These results indicated that DSF/Cu suppressed the metastasis and EMT of hepatic carcinoma through NF‐κB and TGF‐β signalling. Our study indicates the potential of DSF/Cu for therapeutic use.     

MicroRNA‐30c suppresses the pro‐fibrogenic effects of cardiac fibroblasts induced by TGF‐β1 and prevents atrial fibrosis by targeting TGFβRII

Atrial fibrosis serves as an important contributor to atrial fibrillation (AF). Recent data have suggested that microRNA‐30c (miR‐30c) is involved in fibrotic remodelling and cancer development, but the specific role of miR‐30c in atrial fibrosis remains unclear. The purpose of this study was to investigate the role of miR‐30c in atrial fibrosis and its underlying mechanisms through in vivo and in vitro experiments. Our results indicate that miR‐30c is significantly down‐regulated in the rat abdominal aortic constriction (AAC) model and in the cellular model of fibrosis induced by transforming growth factor‐β1 (TGF‐β1). Overexpression of miR‐30c in cardiac fibroblasts (CFs) markedly inhibits CF proliferation, differentiation, migration and collagen production, whereas decrease in miR‐30c leads to the opposite results. Moreover, we identified TGFβRII as a target of miR‐30c. Finally, transferring adeno‐associated virus 9 (AAV9)‐miR‐30c into the inferior vena cava of rats attenuated fibrosis in the left atrium following AAC. These data indicate that miR‐30c attenuates atrial fibrosis via inhibition of CF proliferation, differentiation, migration and collagen production by targeting TGFβRII, suggesting that miR‐30c might be a novel potential therapeutic target for preventing atrial fibrosis.     

rSJYB1 inhibits collagen type I protein expression in hepatic stellate cells via down‐regulating activity of collagen α1 (I) promoter

YB1 is a negative regulator in liver fibrosis. We wondered whether SJYB1, a homologous protein of YB1 from Schistosoma japonicum, has an effect on liver fibrosis in vitro. Recombinant SJYB1 (rSJYB1) protein was expressed in a bacterial system and purified by Ni‐NTA His·Bind Resin. A human hepatic stellate cell line, the LX‐2 cell line, was cultured and treated with rSJYB1. The role of rSJYB1 on LX‐2 cells was then analysed by Western blot and luciferase assay. We succeeded in expressing and purifying SJYB1 in a bacterial system and the purified rSJYB1 could be recognized by S japonicum‐infected rabbit sera. Western bolt analysis showed that rSJYB1 inhibited the expression of collagen type I, but had little effect on α‐smooth muscle actin (α‐SMA). Further analysis revealed that rSJYB1 inhibited the activity of collagen α1 (I) (COL1A1) promoter and functioned at ?1592/?1176 region of COL1A1 promoter. Our data demonstrate that rSJYB1‐mediated anti‐fibrotic activity involves inhibiting the activity of COL1A1 promoter and subsequently suppressing the expression of collagen type I in hepatic stellate cells.     

Nootkatone confers hepatoprotective and anti‐fibrotic actions in a murine model of liver fibrosis by suppressing oxidative stress,inflammation, and apoptosis

In this study, the hepatoprotective and anti‐fibrotic actions of nootkatone (NTK) were investigated using carbon tetrachloride (CCl₄)‐induced liver fibrosis in mice. CCl₄ administration elevated serum aspartate and alanine transaminases levels, respectively. In addition, CCl₄ produced hepatic oxidative and nitrative stress, characterized by diminished hemeoxygenase‐1 expression, antioxidant defenses, and accumulation of 4‐hydroxynonenal and 3‐nitrotyrosine. Furthermore, CCl₄ administration evoked profound expression of pro‐inflammatory cytokine expressions such as tumor necrosis factor‐α, monocyte chemoattractant protein‐1, and interleukin‐1β in hepatic tissues, which corroborated with nuclear factor κB activation. Additionally, CCl₄‐treated animals exhibited higher apoptosis, characterized by increased caspase 3 activity, DNA fragmentation, and poly (ADP‐ribose) polymerase activation. Moreover, histological and biochemical investigations revealed marked fibrosis in the livers of CCl₄‐administered animals. However, NTK treatment mitigated CCl₄‐induced phenotypic changes. In conclusion, our findings suggest that NTK exerts hepatoprotective and anti‐fibrotic actions by suppressing oxidative stress, inflammation, and apoptosis.     

MicroRNA‐30a ameliorates hepatic fibrosis by inhibiting Beclin1‐mediated autophagy

We explored the role of microRNA‐30a (miR‐30a) and the mechanism involved in hepatic fibrosis. MiR‐30a overexpression was achieved by miR‐30a mimics transfection in hepatic stellate cells (HSCs) (HSC‐T6, LX‐2), and miR‐30a agomir (ago‐miR‐30a) treatment in mice. MiR‐30a levels were measured using TaqMan miRNA assay system, and the localization of miR‐30a was detected by fluorescence in situ hybridization (FISH). The interaction of miR‐30a and Beclin1 was confirmed by dual‐luciferase reporter assay. Autophagic flux was analysed using tandem mRFP‐GFP‐LC3 fluorescence microscopy, electron microscopy and Western blot of LC3‐II/I ratio. MiR‐30a was notably down‐regulated in activated HSCs and LX‐2‐exosomes induced by TGF‐β1; overexpression of miR‐30a down‐regulated extracellular matrix (ECM), such as α‐SMA, TIMP‐1, and Collagen I expression, and suppressed cell viability in HSCs. MiR‐30a was significantly down‐regulated in hepatic fibrosis mice and overexpression of miR‐30a prevented BDL‐induced fibrogenesis, concomitant with the down‐regulation of ECM. MiR‐30a inhibited HSCs autophagy and increased lipid accumulation in HSCs and in mice fibrotic hepatic tissues. MiR‐30a inhibited its downstream effector of Beclin1 by direct targeting its 3′‐UTR region. Moreover, Knock‐down of Beclin1 by small interfering RNA (siRNA) inhibited HSC autophagy and activation in LX‐2 cells. In conclusion, miR‐30a is down‐regulated in hepatic fibrosis models and its overexpression prevents liver fibrogenesis by directly suppressing Beclin1‐mediated autophagy; therefore, miR‐30a may be a new potential therapeutic target for controlling hepatic fibrosis.     

New therapeutic strategy of hinokitiol in haemorrhagic shock‐induced liver injury

Haemorrhagic shock and resuscitation (HS/R) may cause global ischaemia‐reperfusion injury, which can result in systemic inflammation, multiorgan failure (particularly liver failure) and high mortality. Hinokitiol, a bioactive tropolone‐related compound, exhibits antiplatelet and anti‐inflammatory activities. Targeting inflammatory responses is a potential strategy for ameliorating hepatic injury during HS/R. Whether hinokitiol prevents hepatic injury during HS/R remains unclear. In the present study, we determined the role of hinokitiol following HS/R. The in vivo assays revealed that hinokitiol markedly attenuated HS/R‐induced hepatic injury. Hinokitiol could inhibited NF‐κB activation and IL‐6 and TNF‐α upregulation in liver tissues. Moreover, hinokitiol reduced caspase‐3 activation, upregulated Bax and downregulated Bcl‐2. These findings suggest that hinokitiol can ameliorate liver injury following HS/R, partly through suppression of inflammation and apoptosis. Furthermore, the in vitro data revealed that hinokitiol significantly reversed hypoxia/reoxygenation (H/R)‐induced cell death and apoptosis in the primary hepatocytes. Hinokitiol prevented H/R‐induced caspase‐3 activation, PPAR cleavage, Bax overexpression and Bcl‐2 downregulation. Moreover, hinokitiol attenuated H/R‐stimulated NF‐κB activation and reduced the levels of IL‐6 and TNF‐α mRNAs, suggesting that hinokitiol can protect hepatocytes from H/R injury. Collectively, our data suggest that hinokitiol attenuates liver injury following HS/R, partly through the inhibition of NF‐κB activation.     

The red wine component ellagic acid induces autophagy and exhibits anti‐lung cancer activity in vitro and in vivo

Red wine consists of a large amount of compounds such as resveratrol, which exhibits chemopreventive and therapeutic effects against several types of cancers by targeting cancer driver molecules. In this study, we tested the anti‐lung cancer activity of 11 red wine components and reported that a natural polyphenol compound ellagic acid (EA) inhibited lung cancer cell proliferation at an efficacy approximately equal to that of resveratrol. EA markedly increased the expression of the autophagosomal marker LC3‐II as well as inactivation of the mechanistic target of rapamycin signalling pathway. EA elevated autophagy‐associated cell death by down‐regulating the expression of cancerous inhibitor of protein phosphatase 2A (CIP2A), and CIP2A overexpression attenuated EA‐induced autophagy of lung cancer cells. Treating tumour‐bearing mice with EA resulted in significant inhibition of tumour growth with suppression of CIP2A levels and increased autophagy. In addition, EA potentiated the inhibitory effects of the natural compound celastrol on lung cancer cells in vitro and in vivo by enhancing autophagy and down‐regulating CIP2A. These findings indicate that EA may be a promising chemotherapeutic agent for lung cancer, and that the combination of EA and celastrol may have applicability for the treatment of this disease.     

Accelerative effect of leflunomide on recovery from hepatic fibrosis involves TRAIL-mediated hepatic stellate cell apoptosis

AimsHepatic fibrosis is reversible, associated with apoptosis of activated hepatic stellate cells (HSCs) as injury subsides, thus providing potential targets for therapy. Little is known, however, about the course of this condition. The objective of this study was to elucidate the mechanism by which Kupffer cells regulate HSC biology during regression of hepatic fibrosis and the effect of leflunomide on this process.Main methodsWe harvested Kupffer cells from rats during spontaneous recovery from liver fibrosis induced by carbon tetrachloride (CCl₄) and prepared recovery Kupffer cell conditioned medium (KCCM). Culture-activated HSCs were pretreated in the absence or presence of A771726, the active metabolite of leflunomide, and then stimulated with recovery KCCM.Key findingsFollowing stimulation with recovery KCCM, HSCs showed a decrease in proliferation and an increase in apoptosis by a caspase-dependent mechanism. Furthermore, pretreatment with A771726 markedly enhanced these effects. Real-time quantitative PCR (Q-PCR) analysis showed increased expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in Kupffer cells during the spontaneous recovery phase. The pro-apoptotic function of KCCM prepared from TRAIL siRNA-treated Kupffer cells was obviously decreased, suggesting that TRAIL played an important role in recovery from hepatic fibrosis. Moreover, A771726 enhanced recovery KCCM-induced apoptosis of HSCs by a mechanism involving the inhibition of nuclear factor-kappa B (NF-κB) activation.SignificanceOur results showed the role of TRAIL in the apoptosis of activated HSCs that is induced by Kupffer cells prepared from livers recovering from CCI₄-induced fibrosis and provided insights into the resolution of fibrosis and the mechanisms by which leflunomide might act upon liver fibrosis.     

Preconditioning influences mesenchymal stem cell properties in vitro and in vivo

Various diseases and toxic factors easily impair cellular and organic functions in mammals. Organ transplantation is used to rescue organ function, but is limited by scarce resources. Mesenchymal stem cell (MSC)‐based therapy carries promising potential in regenerative medicine because of the self‐renewal and multilineage potency of MSCs; however, MSCs may lose biological functions after isolation and cultivation for a long time in vitro. Moreover, after they are injected in vivo and migrate into the damaged tissues or organs, they encounter a harsh environment coupled with death signals due to the inadequate tensegrity structure between the cells and matrix. Preconditioning, genetic modification and optimization of MSC culture conditions are key strategies to improve MSC functions in vitro and in vivo, and all of these procedures will contribute to improving MSC transplantation efficacy in tissue engineering and regenerative medicine. Preconditioning with various physical, chemical and biological factors is possible to preserve the stemness of MSCs for further application in studies and clinical tests. In this review, we mainly focus on preconditioning and the corresponding mechanisms for improving MSC activities in vitro and in vivo; we provide a glimpse into the promotion of MSC‐based cell therapy development for regenerative medicine. As a promising consequence, MSC transplantation can be applied for the treatment of some terminal diseases and can prolong the survival time of patients in the near future.     

Naringin in Ganshuang Granule suppresses activation of hepatic stellate cells for anti‐fibrosis effect by inhibition of mammalian target of rapamycin

A previous study has demonstrated that Ganshuang granule (GSG) plays an anti‐fibrotic role partially by deactivation of hepatic stellate cells (HSCs). In HSCs activation, mammalian target of rapamycin (mTOR)‐autophagy plays an important role. We attempted to investigate the role of mTOR‐autophagy in anti‐fibrotic effect of GSG. The cirrhotic mouse model was prepared to demonstrate the anti‐fibrosis effect of GSG. High performance liquid chromatography (HPLC) analyses were used to identify the active component of GSG. The primary mouse HSCs were isolated and naringin was added into activated HSCs to observe its anti‐fibrotic effect. 3‐methyladenine (3‐MA) and Insulin‐like growth factor‐1 (IGF‐1) was added, respectively, into fully activated HSCs to explore the role of autophagy and mTOR. GSG played an anti‐fibrotic role through deactivation of HSCs in cirrhotic mouse model. The concentration of naringin was highest in GSG by HPLC analyses and naringin markedly suppressed HSCs activation in vitro, which suggested that naringin was the main active component of GSG. The deactivation of HSCs caused by naringin was not because of the autophagic activation but mTOR inhibition, which was supported by the following evidence: first, naringin induced autophagic activation, but when autophagy was blocked by 3‐MA, deactivation of HSCs was not attenuated or reversed. Second, naringin inhibited mTOR pathway, meanwhile when mTOR was activated by IGF‐1, deactivation of HSCs was reversed. In conclusion, we have demonstrated naringin in GSG suppressed activation of HSCs for anti‐fibrosis effect by inhibition of mTOR, indicating a potential therapeutic application for liver cirrhosis.