Enhancement of hepatocyte differentiation from human embryonic stem cells by Chinese medicine Fuzhenghuayu

Mesenchymal stem cell therapy for liver fibrosis need "partner": Results based on a meta-analysis of preclinical studies

BACKGROUND

The efficacy of mesenchymal stem cells (MSCs) in treating liver fibrosis has been demonstrated in several clinical studies. However, their low survival and liver implantation rates remain problematic. In recent years, a large number of studies in animal models of liver fibrosis have shown that MSCs combined with drugs can improve the efficacy of MSCs in the treatment of liver fibrosis alone and inhibit its progression to end-stage liver disease. This has inspired new ways of thinking about treating liver fibrosis.

AIM

To investigate the effectiveness and mechanisms of MSCs combined with drugs in treating liver fibrosis.

METHODS

Data sources included four electronic databases and were constructed until January 2024. The subjects, interventions, comparators, outcomes, and study design principle were used to screen the literature, and the quality of the literature was evaluated to assess the risk of bias. Relevant randomised controlled trials were selected, and the final 13 studies were included in the final study.

RESULTS

A total of 13 studies were included after screening. Pooled analysis showed that MSCs combined with drug therapy significantly improved liver function, promoted the repair of damaged liver tissues, reduced the level of liver fibrosis-related indexes, and effectively ameliorated hepatic fibrosis by modulating the hepatic inflammatory microenvironment, promoting the homing of MSCs, and regulating the relevant signaling pathways, and the treatment efficacy was superior to MSCs alone. However, the combined treatment statistics showed no ame-lioration in serum albumin levels (standardized mean difference = 0.77, 95% confidence interval: -0.13 to 1.68, P = 0.09).

CONCLUSION

In conclusion, MSCs combined with drugs for treating liver fibrosis effectively make up for the shortcomings of MSCs in their therapeutic effects. However, due to the different drugs, the treatment mechanism and effect also differ. Therefore, more randomized controlled trials are needed to compare the therapeutic efficacy of different drugs in combination with MSCs, aiming to select the "best companion" of MSCs in treating hepatic fibrosis.

Progress on traditional Chinese medicine in improving hepatic fibrosis through inhibiting oxidative stress

Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer, characterized by excessive deposition of the extracellular matrix. In the past, hepatic fibrosis was thought to be a static and irreversible pathological process. In recent years, with the rapid development of molecular biology and the continuous in-depth study of the liver at the microscopic level, more and more evidence has shown that hepatic fibrosis is a dynamic and reversible process. Therefore, it is particularly important to find an effective, simple, and inexpensive method for its prevention and treatment. Traditional Chinese medicine (TCM) occupies an important position in the treatment of hepatic fibrosis due to its advantages of low adverse reactions, low cost, and multi-target effectiveness. A large number of research results have shown that TCM monomers, single herbal extracts, and TCM formulas play important roles in the prevention and treatment of hepatic fibrosis. Oxidative stress (OS) is one of the key factors in the occurrence and development of hepatic fibrosis. Therefore, this article reviews the progress in the understanding of the mechanisms of TCM monomers, single herbal extracts, and TCM formulas in preventing and treating hepatic fibrosis by inhibiting OS in recent years, in order to provide a reference and basis for drug therapy of hepatic fibrosis.

Hepatic Polarized Differentiation Promoted the Maturity and Liver Function of Human Embryonic Stem Cell-Derived Hepatocytes via Activating Hippo and AMPK Signaling Pathways

Hepatocytes exhibit a multi-polarized state under the in vivo physiological environment, however, human embryonic stem cell-derived hepatocytes (hEHs) rarely exhibit polarity features in a two-dimensional (2D) condition. Thus, we hypothesized whether the polarized differentiation might enhance the maturity and liver function of hEHs. In this study, we obtained the polarized hEHs (phEHs) by using 2D differentiation in conjunct with employing transwell-based polarized culture. Our results showed that phEHs directionally secreted albumin, urea and bile acids, and afterward, the apical membrane and blood-bile barrier (BBIB) were identified to form in phEHs. Moreover, phEHs exhibited a higher maturity and capacitity of cellular secretory and drug metabolism than those of non-phEHs. Through transcriptome analysis, it was found that the polarized differentiation induced obvious changes in gene expression profiles of cellular adhesion and membrane transport in hEHs. Our further investigation revealed that the activation of Hippo and AMPK signaling pathways made contributions to the regulation of function and cellular polarity in phEHs, further verifying that the liver function of hEHs was closely related with their polarization state. These results not only demonstrated that the polarized differentiation enhanced the maturity and liver function of hEHs, but also identified the molecular targets that regulated the polarization state of hEHs.

Efficacy and Safety of a Botanical Formula Fuzheng Huayu for Hepatic Fibrosis in Patients with CHC: Results of a Phase 2 Clinical Trial

Background. Hepatitis C virus (HCV) is a common cause of progressive hepatic fibrosis, cirrhosis, and hepatocellular carcinoma worldwide. Despite the availability of effective direct-acting antivirals, patients often have significant hepatic fibrosis at the time of diagnosis due to delay in diagnosis and comorbidities which promote fibrogenesis. Thus, antifibrotic agents represent an attractive adjunctive therapy. Fuzheng Huayu (FZHY), a traditional Chinese medicine botanical formulation, has been used as an antifibrotic agent in chronic HBV infection. Our aim was to assess FZHY in patients with HCV infection and active viremia. Method. We randomized 118 patients with active viremia from 8 liver centers in the U.S. to receive oral FZHY (n = 59) or placebo (n = 59) for 48 weeks. Efficacy was assessed by histopathologic changes at the end of therapy. A subset of biopsies was further analyzed using qFibrosis to detect subtle changes in fibrosis in different zones of the hepatic lobules. Results. FZHY was well tolerated and safe. Patients with baseline Ishak fibrosis stages F3 and F4 had better response rates to FZHY than patients with baseline F0–F2 ( $p=0.03$ ). qFibrosis zonal analysis showed significant improvement in fibrosis in all zones in patients with regression of the fibrosis stage. Conclusions. FZHY produced antifibrotic effects in patients with baseline Ishak F3 and F4 fibrosis stages. Reduction in fibrosis severity was zonal and correlated with the severity of inflammation. Based on its tolerability, safety, and efficacy, FZHY should be further investigated as a therapy in chronic liver diseases because of its dual anti-inflammatory and antiibrotic properties. Lay Summary. This is the first US-based, multicenter and placebo-controlled clinical trial that shows statistically significant reduction in fibrosis in patients with active HCV using an antifibrotic botanical formula. This has important implications as there is an immediate need for effective antifibrotic agents in treating many chronic diseases including NASH that lead to scarring of the liver. With artificial intelligence-based methodology, qFibrosis, we may provide a more reliable way to assess the FZHY as a therapy in chronic liver diseases because of its dual anti-inflammatory and antifibrotic properties.

Glycyrrhizin and its derivatives promote hepatic differentiation via sweet receptor, Wnt, and Notch signaling

The acute liver disease is involved in aberrant release of high-mobility group box 1 (HMGB1). Glycyrrhizin (GL), a traditional Chinese medicine for liver disease, binds to HMGB1, thereby inhibits tissue injury. However the mode of action of GL for chronic liver disease remains unclear. We investigated the effects of glycyrrhizin (GL) and its derivatives on liver differentiation using human iPS cells by using a flow cytometric analysis. GL promoted hepatic differentiation at the hepatoblast formation stage. The GL derivatives, 3-O-mono-glucuronyl 18β-glycyrrhetinic acid (Mono) and 3-O-[glucosyl (1 → 2)-glucuronyl] 18β-glycyrrhetinic acid increased AFP⁺ cell counts and albumin⁺ cell counts. Glucuronate conjugation seemed to be a requirement for hepatic differentiation. Mono exhibited the most significant hepatic differentiation effect. We evaluated the effects of (±)-2-(2,4-dichlorophenoxy) propionic acid (DP), a T1R3 antagonist, and sucralose, a T1R3 agonist, on hepatic differentiation, and found that DP suppressed Mono-induced hepatic differentiation, while sucralose promoted hepatic differentiation. Thus, GL promoted hepatic differentiation via T1R3 signaling. In addition, Mono increased β-catenin⁺ cell count and decreased Hes5⁺ cell count suggesting the involvement of Wnt and Notch signaling in GL-induced hepatic differentiation. In conclusion, GL exerted a hepatic differentiation effect via sweet receptor (T1R3), canonical Wnt, and Notch signaling.

Progress of Interference of Traditional Chinese Medicine on Cirrhosis Treated with Bone Marrow Mesenchymal Stem Cells

Transplantation of bone marrow mesenchymal stem cells has attracted more and more attention as a regenerative therapy for the treatment of liver diseases. A large number of studies have shown that this kind of cells can inhibit the activation of hepatic stellate cells and regulate tissue homeostasis and immune system via a variety of ways. Meanwhile, bone marrow mesenchymal stem cells can inhibit apoptosis of hepatocyte, improve liver function, and reduce inflammation through multiple pathways. These cells have a broad prospect in the treatment of liver cirrhosis. At present, there are many studies on the specific mechanism of bone marrow mesenchymal stem cells transplantation in the treatment of liver cirrhosis. This paper reviews the pathogenesis of liver cirrhosis and the mechanism of bone marrow mesenchymal stem cells transplantation in the treatment of liver cirrhosis, discusses the effectiveness of traditional Chinese medicine method in enhancing the efficacy of bone marrow mesenchymal stem cells transplantation, and looks forward to its application prospect in the future.

Tissue-Engineered Bile Ducts for Disease Modeling and Therapy

Recent biotechnical advances in the in vitro culture of cholangiocytes and generation of bioengineered biliary tissue have a high potential for creating biliary tissue to be used for disease modeling, drug screening, and transplantation. For the past few decades, scientists have searched for a source of cholangiocytes, focused on primary cholangiocytes or cholangiocytes derived from hepatocytes or stem cells. At the same time, the development of scaffolds for biliary tissue engineering for transplantation and modeling of cholangiopathies has been explored. In this review, we provide an overview on the current understanding of cholangiocytes sources, the effect of signaling molecules, and transcription factors on cell differentiation, along with the effects of extracellular matrix molecules and scaffolds on bioengineered biliary tissues, and their application in disease modeling and drug screening. Impact statement Over the past few decades, biliary tissue engineering has acquired significant attention, but currently a number of factors hinder this field to eventually generate bioengineered bile ducts that mimic in vivo physiology and are suitable for transplantation. In this review, we present the latest advances with respect to cell source selection, influence of growth factors and scaffolds, and functional characterization, as well as applications in cholangiopathy modeling and drug screening. This review is suited for a broad spectrum of readers, including fundamental liver researchers and clinicians with interest in the current state and application of bile duct engineering and disease modeling.

The effect and mechanisms of Fuzheng Huayu formula against chronic liver diseases

Fuzheng Huayu formula (FZHY) is a traditional Chinese medicine formula composed of Radix Salvia Miltiorrhizae, Cordyceps, Semen Persicae, Gynostemma Pentaphyllammak, Pollen Pini, Fructus Schisandrae Chinensis that is used to treat chronic liver diseases in China. We here describe the pharmacological actions of FZHY in this review. We also describe and provide updates on recent advances in the medical applications and the basic research of mechanisms of FZHY formula. FZHY has been shown to have no serious adverse reactions and exerts antifibrotic effects through targeting more than one molecule.

Sorafenib and fluvastatin synergistically alleviate hepatic fibrosis via inhibiting the TGFβ1/Smad3 pathway

BACKGROUND

Effective strategies for the treatment of hepatic fibrosis are urgently in need.

AIMS

To investigate the effect of the co-treatment of sorafenib and fluvastatin on hepatic fibrosis and the underlying mechanisms.

METHODS

A diethylnitrosamine-induced hepatic fibrosis rat model was used to evaluate the anti-fibrosis effect. Epithelial mesenchymal transition (EMT) of hepatocytes and hepatic stellate cells (HSCs) in response to sorafenib and fluvastatin was explored. A co-treatment effect on TGFβ1 expression was explored in the Kupffer cells of rats. The effect of co-treatment on the regulation of the TGFβ1/Smad3 pathway was investigated in both L02 cells and LX-2 cells.

RESULTS

Sorafenib and fluvastatin synergistically reduced collagen content, α-SMA expression, lamin level, and hyaluronic acid level in the rat hepatic model. Combination treatment significantly inhibited the expression of mesenchymal markers and promoted the expression of epithelial markers in hepatocytes. Co-treatment statistically suppressed the production of TGFβ1 in Kupffer cells. Suppression of EMT in parallel with alleviated up-regulation of fibronectin and α-SMA expression was observed in TGFβ1-activated LX-2 cells. Mechanistically, sorafenib plus fluvastatin blocked the TGFβ1/Smad3 signaling pathway via inhibiting phosphorylation of TβR II in hepatocytes and HSCs.

CONCLUSIONS

Sorafenib and fluvastatin synergistically alleviated diethylnitrosamine-induced hepatic fibrosis in rats. Sorafenib plus fluvastatin may be a potential combination treatment for hepatic fibrotic diseases.

Babao Dan attenuates hepatic fibrosis by inhibiting hepatic stellate cells activation and proliferation via TLR4 signaling pathway

Babao Dan (BBD), a traditional Chinese medicine, has been widely used as a complementary and alternative medicine to treat chronic liver diseases. In this study, we aimed to observe the protective effect of BBD on rat hepatic fibrosis induced by diethylnitrosamine (DEN) and explore it possible mechanism. BBD was administrated while DEN was given. After eight weeks, values of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) indicated that BBD significantly protected liver from damaging by DEN and had no obvious side effect on normal rat livers. Meanwhile, BBD attenuated hepatic inflammation and fibrosis in DEN-induced rat livers through histopathological examination and hepatic hydroxyproline content. Furthermore, we found that BBD inhibited hepatic stellate cells activation and proliferation without altering the concentration of lipopolysaccharide (LPS) in portal vein. In vitro study, serum from BBD treated rats (BBD-serum) could also significantly suppress LPS-induced HSCs activation through TLR4/NF-κB pathway. In addition, BBD-serum also inhibited the proliferation of HSCs by regulating TLR4/ERK pathway. Our study demonstrated that BBD may provide a new therapy strategy of hepatic injury and hepatic fibrosis.

Salvianolic Acid B Enhances Hepatic Differentiation of Human Embryonic Stem Cells Through Upregulation of WNT Pathway and Inhibition of Notch Pathway

Hepatocytes differentiated from human embryonic stem cells (ESCs) could provide a powerful tool for enabling cell-based therapies, studying the mechanisms underlying human liver development and disease, and testing the efficacy and safety of pharmaceuticals. However, currently most in vitro protocols yield hepatocytes with low levels of liver function. In this study, we investigated the potential of Salvianolic acid B (Sal B), an active pharmaceutical compound present in Salvia miltiorrhiza, which has been shown to have an antifibrotic effect in previous studies, to enhance hepatocyte differentiation from human ESCs. After treatment with Sal B, albumin expression and secretion were consistently increased, indicating that Sal B could promote hepatocyte differentiation process. Expression of a large number of important phase 1 and 2 metabolizing enzymes and phase 3 transporters was also increased in treated cells, indicating an enhanced biotransformation function. Our investigations further revealed the activation of Wnt pathway in treated cells, as determined by upregulation of Wnts, which increased amounts of nuclear β-catenin. This increased nuclear β-catenin led in turn to the enhanced expression of T cell factor (TCF) 3 and lymphoid enhancer-binding factor (LEF) 1 which upregulated their downstream targets, cyclin D1 and c-Myc. Notch receptors (Notch1, Notch3), Notch ligand (Jagged2), and Notch receptor targets [hairy and enhancer of split (Hes) 1, 5] were downregulated in treated cells, suggesting that Notch pathway was inhibited. Consistent with the inhibition of Notch pathway, expression of cholangiocyte marker, CK7, was significantly reduced by treatment with Sal B. Numb, a direct transcriptional target of Wnt pathway and a negative regulator of Notch pathway, was upregulated, consistent with activation of Wnt signaling and suppression of Notch signaling. In conclusion, our study demonstrated that Sal B enhanced hepatocyte differentiation from human ESCs through activation of Wnt pathway and inhibition of Notch pathway. Therefore, this study suggests that Sal B can be used as a potential agent to generate more mature hepatocytes for cell-based therapeutics and pharmaceutical studies.

Decellularized human liver extracellular matrix (hDLM)-mediated hepatic differentiation of human induced pluripotent stem cells (hIPSCs)

Liver tissue engineering has emerged as a promising approach in organ transplantation but has been hampered by the lack of a reliable and readily available cell source. Human induced pluripotent stem cells hiPSCs have been highlighted as a desirable source, due to their differentiation potential, ability to self-renew, and the possibility of making patient-specific cells. We developed a decellularization protocol that efficiently removes cellular material while retaining extracellular matrix components. Subsequently, hiPSCs were differentiated on decellularized human liver extracellular matrix (hDLM) scaffolds using an established hepatic differentiation protocol. We demonstrate that using hDLM leads to upregulation markers of hepatic functions when compared with standard differentiation conditions. In addition, expression of a number of hepatic transcription and nuclear factors were found to be within levels comparable with those of primary human adult hepatocytes. Analysis of progression of differentiation on hDLM demonstrated that hepatic developmental marker expression was consistent with hepatic development. The hDLM-derived cells exhibited key hepatic characteristics that were comparable with those observed in primary neonatal human hepatocytes. We investigated the optimal timing of the introduction of hDLM into the differentiation protocol and found that the best results are obtained when cells are plated on hDLM since the earliest stages and accompanied by a progressive loss of sensitivity to substrate composition at later stages. The significance of this work is that it allows for the development of differentiation protocols that take into account signals from extracellular matrix, closely recapitulating of the in vivo micro-environment and resulting in cells that are phenotypically closer to mature hepatocytes.

Phthalazinone Pyrazole Enhances the Hepatic Functions of Human Embryonic Stem Cell-Derived Hepatocyte-Like Cells via Suppression of the Epithelial-Mesenchymal Transition

During liver development, nonpolarized hepatic progenitor cells differentiate into mature hepatocytes with distinct polarity. This polarity is essential for maintaining the intrinsic properties of hepatocytes. The balance between the epithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) plays a decisive role in differentiation of polarized hepatocytes. In this study, we found that phthalazinone pyrazole (PP), a selective inhibitor of Aurora-A kinase (Aurora-A), suppressed the EMT during the differentiation of hepatocyte-like cells (HLCs) from human embryonic stem cells. The differentiated HLCs treated with PP at the hepatoblast stage showed enhanced hepatic morphology and functions, particularly with regard to the expression of drug metabolizing enzymes. Moreover, we found that these effects were mediated though suppression of the AKT pathway, which is involved in induction of the EMT, and upregulation of hepatocyte nuclear factor 4α expression rather than Aurora-A inhibition. In conclusion, these findings provided insights into the regulatory role of the EMT on in vitro hepatic maturation, suggesting that inhibition of the EMT may drive transformation of hepatoblast cells into mature and polarized HLCs.

Herbal remedies for liver fibrosis: A review on the mode of action of fifty herbs

Liver fibrosis is a dynamic pathological condition which can be slowed down in its initial phases. Without proper clinical management of fibrosis, progressive liver damage may lead to cirrhosis and ultimately to liver failure or primary liver cancer, which are irreversible conditions. Therefore, in order to cure fibrotic damage to liver, its early stages should be the centre of attention. In this context, some supplements and ‘complementary and alternative medicine (CAM)’ deserve specific mention, because of their already recognized natural way of healing and long lasting curative effects. Moreover, CAM display negligible side effects and hence it is gaining worldwide importance in clinical practices. In particular, herbal medicines are now replacing synthetic pharmaceuticals and looked upon as the sources of novel bioactive substances. To develop satisfactory herbal combinations for treating liver fibrosis, phytoproducts need to be systematically evaluated for their potency as anti-fibrotic, anti-hepatotoxic and antioxidant agents. More importantly, the identified herb/agent should have the remarkable tendency to stimulate hepatocytes regeneration. The present review is a systematic account of at least fifty medicinal herbs and their products which in experimental models have demonstrated antifibrotic activity and thus, most likely candidates to offer therapeutic protection to liver. Nevertheless, much additional work is still needed to explore molecular pathways to discover potential applications of these medicines so as to open up new vistas in biomedical research.

High-throughput sequencing to identify microRNA signatures during hepatic differentiation of human umbilical cord Wharton's jelly-derived mesenchymal stem cells

AIM

MicroRNAs (miRNAs) constitute a class of small non-coding RNAs involved in regulation of cognate mRNAs post-transcriptionally. MicroRNAs have been implicated in regulating the stem cell differentiation process. Limited regulatory miRNAs have been reported to date during hepatic differentiation of stem cells. The present study was designed to identify the signature miRNAs implicated in hepatic differentiation of stem cells using next-generation sequencing methods.

METHODS

We undertook sequencing of miRNAs isolated from three different time points during hepatic differentiation of human umbilical cord Wharton's jelly-derived mesenchymal stem cells (hUC-MSCs) from two biological replicates.

RESULTS

Out of a total known 2588 miRNAs (according to miRBase version 21), 880 miRNAs were identified in our study. A total of 63 significantly expressed miRNAs during hepatic differentiation, with at least 2-fold change and a false discovery rate value <0.05, were considered for further analysis. The putative target genes of significantly downregulated miRNAs during hepatic differentiation appeared to be mostly associated with biological processes that are essential for hepatic differentiation and maintenance of mature hepatic phenotype-like liver development, stem cell differentiation, Wnt receptor signaling pathway, and drug and cholesterol metabolic processes. Putative target genes of significantly upregulated miRNAs are highly enriched in regulating processes that block hepatic differentiation of hUC-MSCs like epithelial-mesenchymal transition, transforming growth factor-β receptor signaling pathway, and stem cell maintenance.

CONCLUSION

The study provides a new insight for investigation of miRNA-regulated pathways during the differentiation process.

Suppression of Hepatic Epithelial-to-Mesenchymal Transition by Melittin via Blocking of TGFβ/Smad and MAPK-JNK Signaling Pathways

Transforming growth factor (TGF)-β1 plays a crucial role in the epithelial-to-mesenchymal transition (EMT) in hepatocytes and hepatic stellate cells (HSC), which contributes to the pathogenesis of liver fibrosis. Melittin (MEL) is a major component of bee venom and is effective in rheumatoid arthritis, pain relief, cancer cell proliferation, fibrosis and immune modulating activity. In this study, we found that MEL inhibits hepatic EMT in vitro and in vivo, regulating the TGFβ/Smad and TGFβ/nonSmad signaling pathways. MEL significantly inhibited TGF-β1-induced expression of EMT markers (E-cadherin reduction and vimentin induction) in vitro. These results were confirmed in CCl₄-induced liver in vivo. Treatment with MEL almost completely blocked the phosphorylation of Smad2/3, translocation of Smad4 and phosphorylation of JNK in vitro and in vivo. Taken together, these results suggest that MEL suppresses EMT by inhibiting the TGFβ/Smad and TGFβ/nonSmad-c-Jun N-terminal kinase (JNK)/Mitogen-activated protein kinase (MAPK) signaling pathways. These results indicated that MEL possesses potent anti-fibrotic and anti-EMT properties, which may be responsible for its effects on liver diseases.