Mesenchymal stem cell-derived exosomes protect against liver fibrosis via delivering miR-148a to target KLF6/STAT3 pathway in macrophages

Exosome-capturing scaffold promotes endogenous bone regeneration through neutrophil-derived exosomes by enhancing fast vascularization

Exosomes (Exos), extracellular vesicles of endosomal origin, are a promising therapeutic platform for tissue regeneration. In the current study, an exosome-capturing scaffold (ECS) was designed to attract and anchor exosomes via electrostatic adherence followed by lipophilic interactions. Our findings demonstrate that local enrichment of exosomes in the ECS implanted into critical mandibular defects could significantly accelerate endogenous bone regeneration by enhancing vascularization at the defect site. Notably, neutrophil (PMN)-derived exosomes (PMN-Exos) were identified as the predominant exosome subtype among all captured exosomes. During endogenous bone regeneration, PMN-Exos promoted endogenous vascularization primarily by stimulating the proliferation of endothelial progenitor cells (EPCs), which play a pivotal role in the vasculogenesis of new blood vessels. Mechanistically, vascularization involved PMN-Exo-derived miR455-3p, which promotes EPC proliferation by targeting the Smad4 pathway. In conclusion, this study offers an ECS with broad application prospects for enhancing tissue regeneration by accelerating vascularization. The elucidation of underlying mechanisms paves the way for developing novel strategies to regenerate various tissues and organs.

Exosome-based approaches in cancer along with unlocking new insights into regeneration of cancer-prone tissues

Most eukaryotic cells secrete extracellular vesicles called exosomes, which are involved in intercellular communication. Exosomes play a role in tumor development and metastasis by transporting bioactive chemicals from cancerous cells to other cells in local and distant microenvironments. However, the potential of exosomes can be used by engineering them and considering different therapeutic approaches to overcome tumors. Exosomes are a promising drug delivery approach that can help decrease side effects from traditional treatments like radiation and chemotherapy by acting as targeted agents at the tumor site. The present review provides an overview of exosomes and various aspects of the role of exosomes in cancer development, which include these items: exosomes in cancer diagnosis, exosomes and drug delivery, exosomes and drug resistance, exosomal microRNAs and exosomes in tumor microenvironment, etc. Cancer stem cells release exosomes that nurture tumors, promoting unwanted growth and regeneration, and these types of exosomes should be inhibited. Ironically, exosomes from other cells, such as hepatocytes or mesenchymal stem cells (MSCs), are vital for healing organs like the liver and repairing gastric ulcers. Without proper treatment, this healing process can backfire, potentially leading to disease progression or even cancer. What can be found from various studies about the role of exosomes in the field of cancer is that exosomes act like a double-edged sword; on the other hand, natural exosomes in the body may play an important role in the process and progression of cancer, but by engineering exosomes, they can be directed towards target therapy and targeted delivery of drugs to tumor cells. By examining the role and application of exosomes in various mechanisms of cancer, it is possible to help treat this disease more efficiently and quickly in preclinical and clinical research.

New insights into therapeutic strategies for targeting hepatic macrophages to alleviate liver fibrosis

Liver fibrosis is a wound-healing response induced by persistent liver damage, resulting from complex multicellular interactions and multifactorial networks. Without intervention, it can progress to cirrhosis and even liver cancer. Current understanding suggests that liver fibrosis is reversible, making it crucial to explore effective therapeutic strategies for its alleviation. Chronic inflammation serves as the primary driver of liver fibrosis, with hepatic macrophages playing a dual role depending on their polarization state. This review summarizes various prevention and therapeutic strategies targeting hepatic macrophages in the context of liver fibrosis. These strategies include inhibition of macrophage recruitment, modulation of macrophage activation and polarization, regulation of macrophage metabolism, and induction of phagocytosis and autophagy in hepatic macrophages. Additionally, we discuss the communication between hepatic macrophages, hepatocytes, and hepatic stellate cells (HSCs), as well as the current clinical application of anti-fibrotic drugs targeting macrophages. The goal is to identify effective therapeutic targets at each stage of macrophage participation in liver fibrosis development, with the aim of using hepatic macrophages as a target for liver fibrosis treatment.

Autophagy inhibition enhances antifibrotic potential of placental mesenchymal stem cells of fetal origin via regulating TGF-β1 mediated protein degradation of HGF

Mesenchymal stem cell (MSC) therapy represents a promising strategy for pulmonary fibrosis (PF) treatment, with hepatocyte growth factor (HGF) serving as a key mediator of MSC-mediated protection. However, the therapeutic efficacy of MSCs is limited by the complex PF microenvironment, and the mechanisms underlying this limitation remain unclear. This study investigates how the PF pathological microenvironment modulates the antifibrotic potential of placental mesenchymal stem cells of fetal origin (fPMSCs) through HGF regulation and elucidates the molecular mechanisms involved. Morphological analysis, flow cytometry, and multilineage differentiation assays were employed to characterize fPMSCs. Transforming growth factor-β1 (TGF-β1) was employed to simulate the PF microenvironment and activate fPMSCs in vitro. ELISA and Western blotting were used to analyze HGF expression, autophagy markers, and Smad signaling. Autophagosome formation was visualized via confocal microscopy and transmission electron microscopy. Co-immunoprecipitation (Co-IP) assays were performed to assess the interaction between p62 and HGF. The antifibrotic function of fPMSCs was further evaluated using a transwell co-culture system with MRC-5 fibroblasts in vitro and a bleomycin-induced PF mouse model in vivo. Phenotypic characterization confirmed that fPMSCs exhibited canonical MSC morphology, expressed CD73/CD90/CD105, lacked CD14/CD34/CD45/HLA-DR, and differentiated into adipogenic, osteogenic, and chondrogenic lineages. TGF-β1 treatment robustly downregulated the antifibrotic capacity, HGF protein expression, and paracrine secretion in fPMSCs. Recombinant HGF enhanced antifibrotic effects, while an HGF-neutralizing antibody abolished them. TGF-β1 induced autophagy in fPMSCs, promoting HGF degradation via p62 interaction and impairing antifibrotic function in vitro and in vivo. Mechanistically, Smad3 phosphorylation mediated the regulation of autophagy and HGF expression in TGF-β1-treated fPMSCs. Our findings demonstrate that TGF-β1 impairs the antifibrotic function of fPMSCs via autophagy-dependent HGF degradation and Smad3 signaling. Conversely, autophagy inhibition restores HGF levels and enhances fPMSCs' therapeutic efficacy in a preclinical PF model. Targeting autophagy inhibition emerges as a promising therapeutic strategy to counteract pulmonary fibrosis.

Studies on Treatment Within the Scope of Medical Biotechnology for Pancreatic Diseases

The pancreas is made of two compartments: the exocrine pancreas, a source of digestive enzymes, and the endocrine islets which produce vital hormones. Distinct diseases could arise in the pancreas such as diabetes, neuroendocrine tumors, pancreatitis, and pancreatic cancers. Various treatment methods are being researched against these diseases. Treatment with recombinant proteins, therapeutic antibodies, vaccination, gene therapy, tissue engineering, and stem cell treatment are treatment methods. Furthermore, biomarkers are important for both treatment and diagnosis. However, some of the treatment methods mentioned above have not yet been applied to some pancreatic diseases. This review provides insights into the latest advancements in diagnosis and treatment for pancreatic diseases within the scope of medical biotechnology. In addition, some methods that are not yet used for treatment purposes for pancreatic diseases but are used in other diseases that occur in different organs due to similar reasons have been investigated. In this context, possible diagnosis and treatment methods for pancreatic diseases are interpreted. The first aim of this review is to bring together and present the current diagnosis and treatment methods for pancreatic diseases. The second aim is to highlight methods that may have treatment potential by comparing pancreatic diseases that cannot be treated with similar diseases.

Stem cell exosomes: new hope and future potential for relieving liver fibrosis

Liver fibrosis is a chronic liver injury resulting from factors like viral hepatitis, autoimmune hepatitis, non-alcoholic steatohepatitis, fatty liver disease, and cholestatic liver disease. Liver transplantation is currently the gold standard for treating severe liver diseases. However, it is limited by a shortage of donor organs and the necessity for lifelong immunosuppressive therapy. Mesenchymal stem cells (MSCs) can differentiate into various liver cells and enhance liver function when transplanted into patients due to their differentiation and proliferation capabilities. Therefore, it can be used as an alternative therapy for treating liver diseases, especially for liver cirrhosis, liver failure, and liver transplant complications. However, due to the potential tumorigenic effects of MSCs, researchers are exploring a new approach to treating liver fibrosis using extracellular vesicles (exosomes) secreted by stem cells. Many studies show that exosomes released by stem cells can promote liver injury repair through various pathways, contributing to the treatment of liver fibrosis. In this review, we focus on the molecular mechanisms by which stem cell exosomes affect liver fibrosis through different pathways and their potential therapeutic targets. Additionally, we discuss the advantages of exosome therapy over stem cell therapy and the possible future directions of exosome research, including the prospects for clinical applications and the challenges to be overcome.

Exosomal miR-499a-5p from human umbilical cord mesenchymal stem cells attenuates liver fibrosis via targeting ETS1/GPX4-mediated ferroptosis in hepatic stellate cells

Liver fibrosis is a leading cause of liver-related mortality worldwide, yet effective therapies remain limited. Mesenchymal stem cells (MSCs) have recently shown promise in treating liver fibrosis due to their anti-inflammatory and anti-fibrotic properties. However, the precise molecular mechanisms by which MSCs exert their effects remain unclear. In this study, we explored how human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) contribute to treating liver fibrosis, and revealed a crucial role of ferroptosis in modulating hepatic stellate cells (HSCs) activity. We found that MSCs primarily promote ferroptosis in HSCs in an exosome-dependent manner. Specifically, MSC-derived exosomes (MSC-Exos) deliver miR-499a-5p, which interacts with the transcription factor ETS1, leading to the suppression of GPX4, a key regulator of ferroptosis, thereby reducing the fibrogenic activity of HSCs. Overexpression of ETS1 in HSCs counteracted miR-499a-5p-induced ferroptosis, underscoring the pathway's potential as a target for therapeutic intervention. Furthermore, molecular docking simulations further identified optimal ETS1-GPX4 binding sites. This research uncovers a novel mechanism by which MSCs may treat liver fibrosis, providing insights that could guide the development of more effective therapies for this widespread condition.

Mesenchymal stem cell-derived exosomes as a plausible immunomodulatory therapeutic tool for inflammatory diseases

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs), especially, exosomes are considered to have diverse therapeutic effects for various significant diseases. MSC-derived exosomes (MSCex) offer substantial advantages over MSCs due to their long-term preservation, stability, absence of nuclei and fewer adverse effects such as infusion toxicity, thereby paving the way towards regenerative medicine and cell-free therapeutics. These exosomes harbor several cellular contents such as DNA, RNA, lipids, metabolites, and proteins, facilitating drug delivery and intercellular communication. MSCex have the ability to immunomodulate and trigger the anti-inflammatory process hence, playing a key role in alleviating inflammation and enhancing tissue regeneration. In this review, we addressed the anti-inflammatory effects of MSCex and the underlying immunomodulatory pathways. Moreover, we discussed the recent updates on MSCex in treating specific inflammatory diseases, including arthritis, inflammatory bowel disease, inflammatory eye diseases, and respiratory diseases such as asthma and acute respiratory distress syndrome (ARDS), as well as neurodegenerative and cardiac diseases. Finally, we highlighted the challenges in using MSCex as the successful therapeutic tool and discussed future perspectives.

MSC-exosomes pretreated by Danshensu extracts pretreating to target the hsa-miR-27a-5p and STAT3-SHANK2 to enhanced antifibrotic therapy

BACKGROUND

Peritoneal fibrosis (PF) is a serious complication commonly associated with prolonged peritoneal dialysis. Mesenchymal stem cells (MSCs) and their exosomes (Exo) have shown significant therapeutic promise in treating fibrotic conditions. Danshensu (DSS), a bioactive compound from the traditional Chinese herb Danshen reverses fibrosis. This study aims to investigate a novel strategy to enhance the therapeutic efficacy against PF by DSS preconditioning MSCs-derived exosomes (DSS-Exo).

METHODS

The in vitro studies included the effects of DSS duration on MSCs, and the characterization of DSS-Exo and Exo, followed by the assessment of RNA and protein expression levels of peritoneal fibrosis markers and inflammatory cytokines levels after treating human peritoneal mesothelial (HMrSV5) cells. In vivo experiments were conducted on a PF mouse model to observe cell morphology, collagen deposition, fibrosis localization, and to evaluate peritoneal functions such as filtration rate, urea nitrogen clearance, peritoneal thickness, and protein leakage. Mechanistic insights were gained through the analysis of the STAT3/HIF-1α/VEGF signaling pathway, tissue dual-fluorescence localization,chromatin immunoprecipitation sequencing (ChIP-seq), and dual-luciferase reporter (DLR) assays. Additionally, the differential expression of miRNAs between DSS-Exo and Exo was explored and validation of key miRNA.

RESULTS

DSS-Exo significantly upregulated E-cadherin, downregulated VEGFA, α-SMA, CTGF and Fibronectin expression in HMrSV5 cells compared to untreated Exo. In vivo studies revealed that DSS-Exo enhanced the ability of Exo to improve peritoneal function,such as the peritoneal filtration rate and urea nitrogen, glucose clearance, while reducing peritoneal thickness and protein leakage, and cell morphology, reduce collagen deposition, and decrease the degree of fibrosis. Mechanistically, these exosomes inhibited the STAT3/HIF-1α/VEGF signaling pathway within peritoneal mesothelial tissues. Furthermore, ChIP-seq and DLR demonstrated that DSS-Exo affected STAT3 directly binds to SHANK2 promoter regions, forming hydrogen bonds between 5 key amino acids such as GLN-344, HIS-332 and 6 key bases such as DG-258, DG-261. miRNA profiling identified DSS-Exo increased hsa-miR-27a-5p_R-1 to regulated STAT3-SHANK2 and modulating the EMT.

CONCLUSION

This study highlighted the innovative use of Danshensu in enhancing MSC-derived exosome therapy for PF. The identification of the hsa-miR-27a-5p_R-1-STAT3-SHANK2 axis may reveal new molecular mechanisms underlying fibrosis, further research is needed to fully elucidate its impact on PF. The integration of Danshensu from traditional Chinese medicine into modern MSC exosome therapy represents a promising frontier in the development of novel treatments for fibrotic diseases.

Fate and long-lasting therapeutic effects of mesenchymal stromal/stem-like cells: mechanistic insights

A large body of evidence suggests that mesenchymal stromal cells (MSCs) are able to respond rapidly to the cytokine milieu following systemic infusion. This encounter has the potential to dictate their therapeutic efficacy (also referred to as licensing). MSCs are able to rapidly react to cellular damage by migrating to the inflamed tissue and ultimately modifying the inflammatory microenvironment. However, the limited use of MSCs in clinical practice can be attributed to a lack of understanding of the fate of MSCs in patients after administration and long term MSC-derived therapeutic activity. While the known physiological effectors of viable MSCs make a relative contribution, an innate property of MSCs as a therapeutic agent is their caspase-dependent cell death. These mechanisms may be involving the functional reprogramming of myeloid phagocytes via efferocytosis, the process by which apoptotic bodies (ABs) are identified for engulfment by both specialized and non-specialized phagocytic cells. Recent studies have provided evidence that the uptake of ABs with a distinct genetic component can induce changes in gene expression through the process of epigenetic remodeling. This phenomenon, known as 'trained immunity', has a significant impact on immunometabolism processes. It is hypothesized that the diversity of recipient cells within the inflammatory stroma adjacent to MSCs may potentially serve as a biomarker for predicting the clinical outcome of MSC treatment, while also contributing to the variable outcomes observed with MSC-based therapies. Therefore, the long-term reconstructive process of MSCs may potentially be mediated by MSC apoptosis and subsequent phagocyte-mediated efferocytosis.

Cutting-edge insights into liver fibrosis: advanced therapeutic strategies and future perspectives using engineered mesenchymal stem cell-derived exosomes

Liver fibrosis is still a serious health concern worldwide, and there is increasing interest in mesenchymal stem cells (MSCs) with tremendous potential for treating this disease because of their regenerative and paracrine effects. Recently, many researches have focused on using the released exosomes (EXOs) from stem cells to treat liver fibrosis rather than using parent stem cells themselves. MSC-derived EXOs (MSC-EXOs) have demonstrated favourable outcomes similar to cell treatment in terms of regenerative, immunomodulatory, anti-apoptotic, anti-oxidant, anti-necroptotic, anti-inflammatory and anti-fibrotic actions in several models of liver fibrosis. EXOs are superior to their parent cells in several terms, including lower immunogenicity and risk of tumour formation. However, maintaining the stability and efficacy of EXOs after in vivo transplantation remains a major challenge in their clinical applicability. Therefore, several strategies have been applied in EXOs engineering, such as parental cell modification or modifying EXOs directly to achieve optimum performance of EXOs in treating liver fibrosis. Herein, we discuss the underlying mechanisms of liver fibrosis with an overview of the available therapies, among them EXOs. We also summarise the recent developments in improving the effectiveness of EXOs with the advantages and limitations of these approaches in terms of the upcoming clinical applications.

Transdifferentiation of rat keratinocyte progenitors to corneal epithelial cells by limbal niche via the STAT3/PI3K/AKT signaling pathway

PURPOSE

To develop a method for enriching keratinocyte progenitor cells (KPCs) and establish a limbal niche (LN)-mediated transdifferentiation protocol of KPCs into corneal epithelial cells.

METHODS

Limbal niche cells (LNCs) were isolated from limbal tissues through enzymatic digestion and characterized. Conditioned medium from LNCs cultures was collected. KPCs were enriched by rapid adhesion of Matrigel and subsequently cultured in either an LNCs-conditioned medium supplemented with KSFM (LN-KS) or SHEM (LN-SH) for 14 days. Corneal-specific marker expression was assessed to evaluate transdifferentiation efficiency. Key transcription factors and signaling pathways involved in the transdifferentiation process were identified through single-cell and RNA sequencing, and were validated by western blot and quantitative real-time PCR.

RESULTS

Both LN-KS and LN-SH protocols successfully induced corneal epithelial cell transdifferentiation from KPCs, with LN-KS demonstrating higher efficiency in generating CK12 + and p63 + cells (p < 0.001). RNA sequencing analysis and western blot have revealed significant activation of STAT3 and PI3K/AKT signaling pathways. Inhibition of STAT3 blocked the activation of PI3K/AKT signaling pathway and impaired corneal epithelial cell transdifferentiation.

CONCLUSIONS

This study demonstrates the ability of LN to promote KPCs transdifferentiation into corneal epithelial cells in vitro, and this process is partially mediated by the STAT3/PI3K/AKT signaling pathway.

Quercetin-Loaded Melanin Nanoparticles Decorated with Collagenase Mediates Synergistic Immunomodulation and Restores Extracellular Matrix Homeostasis in Liver Fibrosis

Liver fibrosis is a chronic disease that lacks effective drug treatment. Chronic damage and inflammation lead to the formation of collagen and fibrous scars. However, the excessive accumulation of collagen I significantly hinders the delivery of drugs into liver tissue. Therefore, this study developed a quercetin-loaded melanin nanoparticle codecorated collagenase (MNP-QUE-COL) for the treatment of liver fibrosis. These results showed that MNP-QUE-COL degraded excessive collagen I, thereby efficiently delivering melanin and quercetin into the liver tissue. MNP-QUE-COL exhibited optimal PA/MRI dual-mode imaging ability. In addition, the synergistic anti-inflammatory and reactive oxygen species scavenging function of quercetin and melanin was achieved by regulation of M1-M2 macrophage polarization and inhibition of pro-inflammatory cytokine release, reshaping the imbalanced extracellular interstitial inflammatory environment. The results of this research suggest that MNP-QUE-COL is a safe and efficient therapeutic nanoplatform for liver fibrosis, showing promise as a potential therapeutic strategy for liver fibrosis and associated diseases.

Exosomes of human adipose stem cells mitigate irradiation injury to salivary glands by inhibiting epithelial-mesenchymal transition through miR-199a-3p targeting Twist1 and regulating TGFβ1/Smad3 pathway

Rationale: Currently, irradiation-injured salivary glands (IR-SG) lack effective clinical treatment options. Emerging treatments using exosomes (Exo) have shown promising outcomes for various diseases. However, the efficacy of exosome in treating IR-SG remains unexplored. This study aimed to use exosomes to restore IR-SG function and to explore their underlying mechanisms. Methods: Exosomes isolated from human adipose-derived stem cell (ADSC-Exo) were injected into C57BL/6 mice that had their salivary glands injured with 14Gy. RNA sequencing profiled differentially expressed miRNAs and mRNAs of IR-SG. Epithelial-mesenchymal transition (EMT) mechanisms were further examined using SMG-C6 cells. Results: Exo-treated mice had a 96% increase in saliva secretion, higher cell proliferation, upregulated tissue repair/regeneration genes, and preserved functional cells with fewer collagen fibers compared to saline-treated mice. Exo treatment increased the expression of epithelial cell markers while decreasing mesenchymal cell markers. Notably, miR-199a-3p was significantly upregulated in Exo-treated mice, promoting cell growth and reducing EMT. Twist1, an EMT transcription factor, was identified as a direct target of miR-199a-3p and confirmed by luciferase assays. Twist1 overexpression promoted EMT, but Exo treatment or Twist1 knockdown reduced EMT marker expression and inactivated the TGFβ1/Smad3 pathway. Conclusions: ADSC-Exo is a promising therapy for IR-SG, primarily by mitigating EMT through miR-199a-3p targeting Twist1 and regulating the TGFβ1/Smad3 pathway.

Advances in the treatment of liver injury based on mesenchymal stem cell-derived exosomes

Mesenchymal stem cells (MSCs) have shown a great potential role in treating liver injury. MSCs can promote liver regeneration by differentiating into hepatocytes, and can also secrete exosomes to participate in the repair of liver injury. Increasing evidence has shown that mesenchymal stem cell-derived exosomes (MSC-EXOs) play an important role in treating liver injury. In this review, the biogenesis and function of exosomes and the characteristics of MSC-EXOs were analyzed based on recent research results. MSC-EXOs are significant in liver injuries such as liver fibrosis, liver failure, hepatocellular carcinoma, oxidative stress, and lipid steatosis, and participate in the process of liver regeneration.

Exosome-based therapies for inflammatory disorders: a review of recent advances

Exosomes, small extracellular vesicles secreted by cells, have emerged as focal mediators in intercellular communication and therapeutic interventions across diverse biomedical fields. Inflammatory disorders, including inflammatory bowel disease, acute liver injury, lung injury, neuroinflammation, and myocardial infarction, are complex conditions that require innovative therapeutic approaches. This review summarizes recent advances in exosome-based therapies for inflammatory disorders, highlighting their potential as diagnostic biomarkers and therapeutic agents. Exosomes have shown promise in reducing inflammation, promoting tissue repair, and improving functional outcomes in preclinical models of inflammatory disorders. However, further research is needed to overcome the challenges associated with exosome isolation, characterization, and delivery, as well as to fully understand their mechanisms of action. Current limitations and future directions in exosome research underscore the need for enhanced isolation techniques and deeper mechanistic insights to harness exosomes' full therapeutic potential in clinical applications. Despite these challenges, exosome-based therapies hold great potential for the treatment of inflammatory disorders and may offer a new paradigm for personalized medication.

Long-term expanded hepatic progenitor cells ameliorate D-GalN/LPS-induced acute liver failure through repolarizing M1 macrophage to M2-Like phenotype via activation of the IL-10/JAK2/STAT3 signaling pathway

Acute liver failure (ALF) is a devastating liver disease characterized by the rapid deterioration of hepatocytes, which causes a series of clinical complications, including hepatic dysfunction, coagulopathy, encephalopathy, and multiorgan failure. Cell-based therapy is a promising alternative as it can bridge patients until their livers regenerate, releasing immunomodulatory molecules to suppress inflammation. This study reports an iPSCs-derived long-term expanded hepatic progenitor cell (LTHepPCs), which can differentiate into hepatocyte-like cells (HLCs) in vivo. When introduced into drug-induced ALF models, LTHepPCs mitigate liver damage by modulating the local immune microenvironment. This is achieved by shifting macrophages/Kupffer cells towards an anti-inflammatory state, resulting in a decrease in the expression of inflammatory cytokines such as TNF-a, IL-1β, and IL-8, and an increase in the expression of anti-inflammatory cytokines such as IL-10 and ARG-1. In vitro co-culturing of THP-1 or mBMDMs with LTHepPCs suggested that LTHepPCs could activate the anti-inflammatory state of macrophages/Kupffer cells via the IL-10/JAK2/STAT3 signaling pathway. Therefore, LTHepPC transplantation is a promising therapy for ALF patients.

Cell therapy for end-stage liver disease: Current state and clinical challenge

ABSTRACT

Liver disease involves a complex interplay of pathological processes, including inflammation, hepatocyte necrosis, and fibrosis. End-stage liver disease (ESLD), such as liver failure and decompensated cirrhosis, has a high mortality rate, and liver transplantation is the only effective treatment. However, to overcome problems such as the shortage of donor livers and complications related to immunosuppression, there is an urgent need for new treatment strategies that need to be developed for patients with ESLD. For instance, hepatocytes derived from donor livers or stem cells can be engrafted and multiplied in the liver, substituting the host hepatocytes and rebuilding the liver parenchyma. Stem cell therapy, especially mesenchymal stem cell therapy, has been widely proved to restore liver function and alleviate liver injury in patients with severe liver disease, which has contributed to the clinical application of cell therapy. In this review, we discussed the types of cells used to treat ESLD and their therapeutic mechanisms. We also summarized the progress of clinical trials around the world and provided a perspective on cell therapy.

Molecular Mechanisms of Fibrosis in Cholestatic Liver Diseases and Regenerative Medicine-Based Therapies

The aim of this review is to explore the potential of new regenerative medicine approaches in the treatment of cholestatic liver fibrosis. Cholestatic liver diseases, such as primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and biliary atresia (BA), due to the accumulation of bile, often progress to liver fibrosis, cirrhosis, and liver failure. When the disease becomes severe enough to require liver transplantation. Deeply understanding the disease's progression and fibrosis formation is crucial for better diagnosis and treatment. Current liver fibrosis treatments mainly target the root causes and no direct treatment method in fibrosis itself. Recent advances in regenerative medicine offer a potential approach that may help find the ways to target fibrosis directly, offering hope for improved outcomes. We also summarize, analyze, and discuss the current state and benefits of regenerative medicine therapies such as mesenchymal stem cell (MSC) therapy, induced pluripotent stem cells (iPSCs), and organoid technology, which may help the treatment of cholestatic liver diseases. Focusing on the latest research may reveal new targets and enhance therapeutic efficacy, potentially leading to more effective management and even curative strategies for cholestatic liver diseases.

The Role of Extracellular Vesicles in Liver Fibrosis: Friends or Foes?

Liver fibrosis represents a common pathway in the progression of various chronic liver diseases towards cirrhosis and liver failure. Extracellular vesicles (EVs) are membrane-enclosed particles secreted by diverse cell types, including exosomes, microvesicles, apoptotic vesicles, and the recently identified migrasomes. These vesicles can be taken up by recipient cells, thereby modulating their function through the transport of cargo molecules. EVs facilitate intercellular communication and play a significant role in the development of liver fibrosis. Moreover, the detection of EVs in various body fluids offers sensitive diagnostic tools for assessing liver fibrosis. Additionally, EVs may serve as therapeutic targets, potential therapeutic agents, and drug delivery vehicles. This article reviews recent advances in the field of EVs concerning liver fibrosis and related diseases, with a particular focus on the potential role of the newly discovered migrasomes in intracellular crosstalk within the liver.

Exploring the cytoprotective role of mesenchymal stem Cell-Derived exosomes in chronic liver Fibrosis: Insights into the Nrf2/Keap1/p62 signaling pathway

Hepatic fibrosis is a common pathology present in most chronic liver diseases. Autophagy is a lysosome-mediated intracellular catabolic and recycling process that plays an essential role in maintaining normal hepatic functions. Nuclear factor erythroid 2-like 2 (Nrf2) is a transcription factor responsible for the regulation of cellular anti-oxidative stress response. This study was designed to assess the cytoprotective effect of mesenchymal stem cell-derived exosomes (MSC-exos) on endothelial-mesenchymal transition (EMT) in Carbon Tetrachloride (CCL4) induced liver fibrosis. Rats were treated with 0.1 ml of CCL4 twice weekly for 8 weeks, followed by administration of a single dose of MSC-exos. Rats were then sacrificed after 4 weeks, and liver samples were collected for gene expression analyses, Western blot, histological studies, immunohistochemistry, and transmission electron microscopy. Our results showed that MSC-exos administration decreased collagen deposition, apoptosis, and inflammation. Exosomes modulate the Nrf2/Keap1/p62 pathway, restoring autophagy and Nrf2 levels through modulation of the non-canonical pathway of Nrf2/Keap1/p62. Additionally, MSC-exos regulated miR-153-3p, miR-27a, miR-144 and miRNA-34a expression. In conclusion, the present study shed light on MSC-exos as a cytoprotective agent against EMT and tumorigenesis in chronic liver inflammation.

Mesenchymal Stem Cells and Their Derived Exosomes Mitigated Hepatic Cirrhosis in Rats by Altering the Expression of miR-23b and miR-221

Background

The therapeutic effect of mesenchymal stem cells (MSCs) in liver cirrhosis is limited by their entrapment in the pulmonary vessels. Thus, the use of MSC-derived exosomes has become a promising strategy. The current work aimed to compare the role of human umbilical cord blood-MSCs (hUCB-MSCs) and their derived exosomes in the alleviation of liver cirrhosis focusing on the role of miR-23b and miR-221 and their direct effectors in inflammatory and autophagic pathways.

Methods

Rats were divided into six groups normal controls (negative control), liver cirrhosis group (positive control), liver cirrhotic rats that received conditioned media, liver cirrhotic rats that received hUCB-MSCs, cirrhotic rats that received exosomes, and cirrhotic rats that received both hUCB-MSCs and exosomes. The messenger RNA expression of transforming growth factor-β (TGF-β), Matrix metalloproteinase 9 (MMP 9), fibronectin, collagen type-1 (col1), alpha-smooth muscle actin (α-SMA), Suppressor of Mothers Against Decapentaplegic (SMAD) 2 and 7, Beclin, P62, and light chain 3 (LC3) were evaluated by quantitative real-time polymerase chain reaction. Immunohistochemical staining for Beclin, P62, and LC3 was performed.

Results

The treatment of cirrhotic rats with hUCB-MSCs, exosomes, or the combination of them significantly downregulated miRNA-221, fibronectin, collagen I, α-SMA, Smad2 (P<0.001, for each), and P62 (P=0.032, P<0.001, P<0.001, respectively). Additionally, the treatment of cirrhotic rats with hUCB-MSCs, exosomes, or the combination of them significantly upregulated mTOR, Beclin, LC3, and Smad7 (P<0.001, for each) and miRNA-23 (P=0.021, P<0.001, P<0.001, respectively).

Conclusion

hUCB-MSCs and their derived exosomes ameliorated liver cirrhosis by anti-inflammatory and anti-fibrotic effects besides modulation of autophagy. The exosomes had a better improvement effect either alone or combined with hUCB-MSCs, as proved by improvement in liver function tests, and molecular, histopathological, and immunohistochemical profiles.

Liver fibrosis pathologies and potentials of RNA based therapeutics modalities

Liver fibrosis (LF) occurs when the liver tissue responds to injury or inflammation by producing excessive amounts of scar tissue, known as the extracellular matrix. This buildup stiffens the liver tissue, hinders blood flow, and ultimately impairs liver function. Various factors can trigger this process, including bloodborne pathogens, genetic predisposition, alcohol abuse, non-steroidal anti-inflammatory drugs, non-alcoholic steatohepatitis, and non-alcoholic fatty liver disease. While some existing small-molecule therapies offer limited benefits, there is a pressing need for more effective treatments that can truly cure LF. RNA therapeutics have emerged as a promising approach, as they can potentially downregulate cytokine levels in cells responsible for liver fibrosis. Researchers are actively exploring various RNA-based therapeutics, such as mRNA, siRNA, miRNA, lncRNA, and oligonucleotides, to assess their efficacy in animal models. Furthermore, targeted drug delivery systems hold immense potential in this field. By utilizing lipid nanoparticles, exosomes, nanocomplexes, micelles, and polymeric nanoparticles, researchers aim to deliver therapeutic agents directly to specific biomarkers or cytokines within the fibrotic liver, increasing their effectiveness and reducing side effects. In conclusion, this review highlights the complex nature of liver fibrosis, its underlying causes, and the promising potential of RNA-based therapeutics and targeted delivery systems. Continued research in these areas could lead to the development of more effective and personalized treatment options for LF patients.

A systematic review of the anti-inflammatory and anti-fibrotic potential of human umbilical cord mesenchymal stem cells-derived exosomes in experimental models of liver regeneration

Chronic liver injuries and their complications are leading causes of death, especially in developing countries (Sharma and Nagalli in Sex/Gender-Specific Medicine in the Gastrointestinal Diseases, StatPearls Publishing, 2023). The available and effective treatment plans are limited, implicating the need for innovative treatment approaches (Tsuchiya et al. in Inflamm Regener, 2019;Sharma and Nagalli in Sex/Gender-Specific Medicine in the Gastrointestinal Diseases, StatPearls Publishing, 2023;Younossi et al. in Clin Gastroenterol Hepatol 21:1978-1991, 2023;). This paper aims to summarize the effects and mechanisms of hUC-MSC-exo on liver injuries and its complications; it also suggests future directions for future research. The outcomes of interest are the morphology and histology of the liver, pathology score, liver function enzyme, glucose and lipid metabolism, and the effect hUC-MSC-exo had on gene regulation regarding liver diseases. A comprehensive review of nineteen studies was conducted to assess the effectiveness of the implementation of the hUC-MSC-Exo, instilling confidence in the validity of the findings. Regarding the morphology and histology of the liver and pathology score, hUC-MSC-exo treatment resulted in improved liver morphology post-treatment, as indicated by the reduction in pathology scores. However, these observed improvements in the liver surface are not directly attributed to the hUC-MSC-Exo itself but to the overall healing processes stimulated by the treatment. In physiological outcomes, hUC-MSC-exo also improves glucose and lipid metabolism, especially in diet-induced liver injury and its complications. In gene regulation, one interesting gene in this intervention is the fat mass and obesity-associated (FTO), in which hUC-MSC-exo combined with miRNAs can suppress FTO. HUC-MSC-Exo can improve by utilizing several possible pathways, targeting pinpoints in the pathogenesis of liver disease or glucose and lipid metabolism. This study presents hUC-MSC-exo better in all outcomes of interest compared to the control or sham group. Further specification of indications of the hUC-MSC-exo method may be beneficial and essential to be analyzed in future reviews to better understand the effectiveness of each hUC-MSC-exo dose, duration, and medium.

Formononetin Alleviates Ischemic Acute Kidney Injury by Regulating Macrophage Polarization through KLF6/STAT3 Pathway

Recent research has indicated that formononetin demonstrates a potent anti-inflammatory effect in various diseases. However, its impact on sterile inflammation kidney injury, specifically acute kidney injury (AKI), remains unclear. In this study, we utilized an ischemia/reperfusion-induced AKI (IRI-AKI) mouse model and bone marrow-derived macrophages (BMDMs) to investigate the effects of formononetin on sterile inflammation of AKI and to explore the underlying mechanism. The administration of formononetin significantly preserved kidney function from injury, as evidenced by lower serum creatinine and blood urea nitrogen levels compared to IRI-AKI mice without treatment. This was further confirmed by less pathological changes in renal tubules and low expression of tubular injury markers such as KIM-1 and NGAL in the formononetin-treated IRI-AKI group. Furthermore, formononetin effectively suppressed the expression of pro-inflammatory cytokines (MCP-1, TNF-α, and IL-1β) and macrophage infiltration into the kidneys of AKI mice. In vitro studies showed that formononetin led to less macrophage polarization towards a pro-inflammatory phenotype in BMDMs stimulated by LPS and IFN-[Formula: see text]. The mechanism involved the KLF6 and p-STAT3 pathway, as overexpression of KLF6 restored pro-inflammatory cytokine levels and pro-inflammatory polarization. Our findings demonstrate that formononetin can significantly improve renal function and reduce inflammation in IRI-AKI, which may be attributed to the inhibition of KLF6/STAT3-mediated macrophage pro-inflammatory polarization. This discovery presents a new promising therapeutic option for the treatment of IRI-AKI.

Targeting Reprogrammed Cancer-Associated Fibroblasts with Engineered Mesenchymal Stem Cell Extracellular Vesicles for Pancreatic Cancer Treatment

Background: As one of the most aggressive and lethal cancers, pancreatic cancer is highly associated with cancer-associated fibroblasts (CAFs) that influence the development and progression of cancer. Targeted reprogramming of CAFs may be a promising strategy for pancreatic cancer. This study aims to construct engineered extracellular vesicles (EVs) with surface modification of integrin α5 (ITGA5)-targeting peptide and high internal expression of miR-148a-3p by endogenous modification for targeted reprogramming of pancreatic CAFs. Methods: Bone marrow mesenchymal stem cells (BMSCs) and pancreatic CAFs were cocultured to examine the effect of BMSC-derived EVs on the expression levels of CAF markers. miR-148a-3p was identified as a functional molecule. The mechanism of miR-148a-3p was elucidated using the dual-luciferase reporter assay. BMSCs were infected with TERT-encoding and miR-148a-3p-encoding lentiviruses. Subsequently, BMSCs were modified with ITGA5-specific targeting peptide. The supernatant was ultracentrifuged to obtain the engineered EVs (ITGA5-EVs-148a), which were used to reprogram CAFs. Results: BMSCs modulated CAF marker expressions through EVs. miR-148a-3p was up-regulated in BMSCs. The expression of miR-148a-3p in pancreatic CAFs was down-regulated when compared with that in normal fibroblasts (NFs). Mechanistically, ITGA5-EVs-148a effectively suppressed the proliferation and migration of pancreatic CAFs by targeting ITGA5 through the TGF-β/SMAD pathway. ITGA5-EVs-148a was associated with enhanced cellular uptake and exhibited enhanced in vitro and in vivo targeting ability. Moreover, ITGA5-EVs-148a exerted strong reconfiguration effects in inactivating CAFs and reversing tumor-promoting effects in 3D heterospheroid and xenograft pancreatic cancer models. Conclusions: This targeted CAF reprogramming strategy with genetically engineered ITGA5-EVs-148a holds great promise as a precision therapeutics in clinical settings.

iMSC exosome delivers hsa-mir-125b-5p and strengthens acidosis resilience through suppression of ASIC1 protein in cerebral ischemia-reperfusion

Acid-sensing ion channel 1 (ASIC1) is critical in acidotoxicity and significantly contributes to neuronal death in cerebral stroke. Pharmacological inhibition of ASIC1 has been shown to reduce neuronal death. However, the potential of utilizing exosomes derived from pluripotent stem cells to achieve inhibition of Asic1 remains to be explored. Developing qualified exosome products with precise and potent active ingredients suitable for clinical application is also ongoing. Here, we adopt small RNA-seq to interrogate the miRNA contents in exosomes of pluripotent stem cell induced mesenchymal stem cell (iMSC). RNA-seq was used to compare the oxygen-glucose deprivation-damaged neurons before and after the delivery of exosomes. We used Western blot to quantify the Asic1 protein abundance in neurons before and after exosome treatment. An in vivo test on rats validated the neuroprotective effect of iMSC-derived exosome and its active potent miRNA hsa-mir-125b-5p. We demonstrate that pluripotent stem cell-derived iMSCs produce exosomes with consistent miRNA contents and sustained expression. These exosomes efficiently rescue injured neurons, alleviate the pathological burden, and restore neuron function in rats under oxygen-glucose deprivation stress. Furthermore, we identify hsa-mir-125b-5p as the active component responsible for inhibiting the Asic1a protein and protecting neurons. We validated a novel therapeutic strategy to enhance acidosis resilience in cerebral stroke by utilizing exosomes derived from pluripotent stem cells with specific miRNA content. This holds promise for cerebral stroke treatment with the potential to reduce neuronal damage and improve clinical patient outcomes.

Therapeutic Potential of Mesenchymal Stem Cell-Derived Exosomes as Nanomedicine for Peripheral Nerve Injury

Peripheral nerve injury (PNI) is a complex and protracted process, and existing therapeutic approaches struggle to achieve effective nerve regeneration. Recent studies have shown that mesenchymal stem cells (MSCs) may be a pivotal choice for treating peripheral nerve injury. MSCs possess robust paracrine capabilities, and exosomes, as the primary secretome of MSCs, are considered crucial regulatory mediators involved in peripheral nerve regeneration. Exosomes, as nanocarriers, can transport various endogenous or exogenous bioactive substances to recipient cells, thereby promoting vascular and axonal regeneration while suppressing inflammation and pain. In this review, we summarize the mechanistic roles of exosomes derived from MSCs in peripheral nerve regeneration, discuss the engineering strategies for MSC-derived exosomes to improve therapeutic potential, and explore the combined effects of MSC-derived exosomes with biomaterials (nerve conduits, hydrogels) in peripheral nerve regeneration.

Adipose-derived extracellular vesicles - a novel cross-talk mechanism in insulin resistance, non-alcoholic fatty liver disease, and polycystic ovary syndrome

Obesity is the best described risk factor for the development of non-alcoholic fatty liver disease (NAFLD)/metabolic dysfunction associated steatotic liver disease (MASLD) and polycystic ovary syndrome (PCOS) while the major pathogenic mechanism linking these entities is insulin resistance (IR). IR is primarily caused by increased secretion of proinflammatory cytokines, adipokines, and lipids from visceral adipose tissue. Increased fatty acid mobilization results in ectopic fat deposition in the liver which causes endoplasmic reticulum stress, mitochondrial dysfunction, and oxidative stress resulting in increased cytokine production and subsequent inflammation. Similarly, IR with hyperinsulinemia cause hyperandrogenism, the hallmark of PCOS, and inflammation in the ovaries. Proinflammatory cytokines from both liver and ovaries aggravate IR thus providing a complex interaction between adipose tissue, liver, and ovaries in inducing metabolic abnormalities in obese subjects. Although many pathogenic mechanisms of IR, NAFLD/MASLD, and PCOS are known, there is still no effective therapy for these entities suggesting the need for further evaluation of their pathogenesis. Extracellular vesicles (EVs) represent a novel cross-talk mechanism between organs and include membrane-bound vesicles containing proteins, lipids, and nucleic acids that may change the phenotype and function of target cells. Adipose tissue releases EVs that promote IR, the development of all stages of NAFLD/MASLD and PCOS, while mesenchymal stem cell-derived AVs may alleviate metabolic abnormalities and may represent a novel therapeutic device in NAFLD/MASLD, and PCOS. The purpose of this review is to summarize the current knowledge on the role of adipose tissue-derived EVs in the pathogenesis of IR, NAFLD/MASLD, and PCOS.

Adipose Tissue and Umbilical Cord Tissue: Potential Sources of Mesenchymal Stem Cells for Liver Fibrosis Treatment

Background/Aims

Mesenchymal stem cells (MSCs) are potential alternatives for liver fibrosis treatment; however, their optimal sources remain uncertain. This study compares the ex-vivo expansion characteristics of MSCs obtained from adipose tissue (AT) and umbilical cord (UC) and assesses their therapeutic potential for liver fibrosis treatment.

Methods

Since MSCs from early to mid-passage numbers (P2-P6) are preferable for cellular therapy, we investigated the growth kinetics of AT-MSCs and UC-MSCs up to P6 and evaluated their therapeutic effects in a rat model of liver fibrosis induced by diethylnitrosamine.

Results

Results from the expansion studies demonstrated that both cell types exhibited bona fide characteristics of MSCs, including surface antigens, pluripotent gene expression, and differentiation potential. However, AT-MSCs demonstrated a shorter doubling time (58.2 ± 7.3 vs. 82.3 ± 4.3 h; P < 0.01) and a higher population doubling level (10.1 ± 0.7 vs. 8.2 ± 0.3; P < 0.01) compared to UC-MSCs, resulting in more cellular yield (230 ± 9.0 vs. 175 ± 13.2 million) in less time. Animal studies demonstrated that both MSC types significantly reduced liver fibrosis (P < 0.05 vs. the control group) while also improving liver function and downregulating fibrosis-associated gene expression.

Conclusion

AT-MSCs and UC-MSCs effectively reduce liver fibrosis. However, adipose cultures display an advantage by yielding a higher number of MSCs in a shorter duration, rendering them a viable choice for scenarios requiring immediate single-dose administration, often encountered in clinical settings.

The science of exosomes: Understanding their formation, capture, and role in cellular communication

Extracellular vesicles (EVs) serve as a crucial method for transferring information among cells, which is vital in multicellular organisms. Among these vesicles, exosomes are notable for their small size, ranging from 20 to 150 nm, and their role in cell-to-cell communication. They carry lipids, proteins, and nucleic acids between cells. The creation of exosomes begins with the inward budding of the cell membrane, which then encapsulates various macromolecules as cargo. Once filled, exosomes are released into the extracellular space and taken up by target cells via endocytosis and similar processes. The composition of exosomal cargo varies, encompassing diverse macromolecules with specific functions. Because of their significant roles, exosomes have been isolated from various cell types, including cancer cells, endothelial cells, macrophages, and mesenchymal cells, with the aim of harnessing them for therapeutic applications. Exosomes influence cellular metabolism, and regulate lipid, glucose, and glutamine pathways. Their role in pathogenesis is determined by their cargo, which can manipulate processes such as apoptosis, proliferation, inflammation, migration, and other molecular pathways in recipient cells. Non-coding RNA transcripts, a common type of cargo, play a pivotal role in regulating disease progression. Exosomes are implicated in numerous biological and pathological processes, including inflammation, cancer, cardiovascular diseases, diabetes, wound healing, and ischemic-reperfusion injury. As a result, they hold significant potential in the treatment of both cancerous and non-cancerous conditions.

Effects of Mesenchymal Stem Cells-Derived Extracellular Vesicles on Inhibition of Hepatic Fibrosis by Delivering miR-200a

BACKGROUND

Hepatic fibrosis (HF) is a common pathological feature of chronic hepatic diseases. We aimed to illuminate the significance of amniotic mesenchymal stem cells (AMSCs)-derived extracellular vesicles (AMSCs-EVs) in HF.

METHODS

Human AMSCs-EVs were isolated and identified. HF mice were constructed and treated with EVs. The fibrosis was observed by staining experiments and Western blot (WB) assay. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and hepatic hydroxyproline (Hyp) were detected to confirm liver function. For the in vitro experiments, human hepatic stellate cells were induced with transforming growth factor-β and treated with EVs. To measure the degree of HF, the expression of alpha-smooth muscle actin (α-SMA) and Collagen I was detected by WB assay, and cell proliferation was detected by cell counting kit 8 assay. The levels of miR-200a, Zinc finger E-box binding homeobox 1 (ZEB1), and phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) were detected by WB and real-time quantitative polymerase chain reaction. The binding of ZEB1 to PIK3R3 and miR-200a to ZEB1 was analyzed by chromatin immunoprecipitation and dual luciferase assays to validate their relationships.

RESULTS

Human AMSCs and AMSCs-EVs were obtained. Serum ALT, AST, TBIL, and hepatic Hyp were increased, implying the fibrosis degree was aggravated in HF mice, which was decreased again after EV treatment. EVs inhibited HF degree by reducing α-SMA and Collagen I and promoting cell proliferation. AMSCs-EVs delivered miR-200a into hepatocytes, which up-regulated miR-200a expression, inhibited ZEB1 expression, and reduced its enrichment on the PIK3R3 promoter, therefore inhibiting PIK3R3 expression and alleviating HF. Overexpression of ZEB1 or PIK3R3 attenuated the anti-fibrotic effect of AMSCs-EVs.

CONCLUSION

Human AMSCs-derived EVs mediated miR-200a delivery and inhibition of intracellular ZEB1/PIK3R3 axis to exert anti-fibrosis effects.

Mesenchymal stem cell-derived exosomal miR-26a induces ferroptosis, suppresses hepatic stellate cell activation, and ameliorates liver fibrosis by modulating SLC7A11

Liver fibrosis is a key contributor to hepatic disease-related mortality. Exosomes derived from mesenchymal stem cells (MSCs) have been revealed to improve liver fibrosis. To explore the effect and mechanism of MSC-derived exosomal miR-26a on liver fibrosis, exosomes were separated from bone marrow-derived MSCs (BMSCs) and used to treat with LX2 cells. The miR-26a level was decreased in BMSC-derived exosomes. Treatment with exosomes isolated from human BMSCs transfected with miR-26a mimics (miR-26a mimic-Exo) decreased the 5-ethynyl-2'-deoxyuridine-positive cell rate, the protein level of α-SMA and collagen I, and the glutathione (GSH) level but enhanced the apoptosis rate and the reactive oxide species (ROS) level in LX2 cells, which were reversed by the treatment of deferoxamine. Mechanically, miR-26a directly bound SLC7A11 mRNA and negatively modulated the level of SLC7A11 in LX2 cells. Overexpression of SLC7A11 reversed the miR-26a mimic-Exo-induced alterations in the level of ROS, Fe2+, malonaldehyde, and GSH in LX2 cells. In vivo, miR-26a mimic-Exo decreased the level of SLC7A11 and attenuated CCL4-induced liver fibrosis. Collectively, miR-26a mimic-Exo induced ferroptosis to alleviate liver fibrosis by regulating SLC7A11, which may provide new strategies for the treatment of liver fibrosis, and even other relevant diseases.

Native and engineered extracellular vesicles: novel tools for treating liver disease

Liver diseases are classified as acute liver damage and chronic liver disease, with recurring liver damage causing liver fibrosis and progression to cirrhosis and hepatoma. Liver transplantation is the only effective treatment for end-stage liver diseases; therefore, novel therapies are required. Extracellular vesicles (EVs) are endogenous nanocarriers involved in cell-to-cell communication that play important roles in immune regulation, tissue repair and regeneration. Native EVs can potentially be used for various liver diseases owing to their high biocompatibility, low immunogenicity and tissue permeability and engineered EVs with surface modification or cargo loading could further optimize therapeutic effects. In this review, we firstly introduced the mechanisms and effects of native EVs derived from different cells and tissues to treat liver diseases of different etiologies. Additionally, we summarized the possible methods to facilitate liver targeting and improve cargo-loading efficiency. In the treatment of liver disease, the detailed engineered methods and the latest delivery strategies were also discussed. Finally, we pointed out the limitations and challenges of EVs for future development and applications. We hope that this review could provide a useful reference for the development of EVs and promote the clinical translation.

Umbilical cord mesenchymal stem cell-derived exosomes inhibits fibrosis in human endometrial stromal cells via miR-140-3p/FOXP1/Smad axis

Endometrial fibrosis is the histologic appearance of intrauterine adhesion (IUA). Emerging evidences demonstrated umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-exo) could alleviate endometrial fibrosis. But the specific mechanism is not clear. In this study, we explored the effect of UCMSC-exo on endometrial fibrosis, and investigated the possible role of miR-140-3p/FOXP1/Smad axis in anti-fibrotic properties of UCMSC-exo. UCMSC-exo were isolated and identified. Transforming growth factor-β (TGF-β) was used to induce human endometrial stromal cell (HESC) fibrosis. Dual luciferase assay was performed to verify the relationship between miR-140-3p and FOXP1. The expressions of fibrotic markers, SIP1, and p-Smad2/p-Smad3 in HESCs stimulated with UCMSC-exo were detected by western blot. In addition, the effects of miR-140-3p mimic, miR-140-3p inhibitor and FOXP1 over-expression on endometrial fibrosis were assessed. The isolated UCMSC-exo had a typical cup-shaped morphology and could be internalized into HESCs. The expressions of fibrotic markers were significantly increased by TGF-β, which was reversed by UCMSC-exo. MiR-140-3p in UCMSC-exo ameliorated TGf-β-induced HESCs fibrosis. FOXP1 was identified as the direct target of miR-140-3p, which could inversely regulate miR-140-3p's function on HESCs fibrosis. Furthermore, we demonstrated that miR-140-3p in UCMSC-exo regulated Smad signal pathway to exert the anti-fibrotic effect in HESCs. The anti-fibrotic effect of UCMSC-derived exosomes against HESC fibrosis was at least partially achieved by miR-140-3p/FOXP1/Smad axis.

Enhancing Skin Injury Repair: Combined Application of PF-127 Hydrogel and hADSC-Exos Containing miR-148a-3p

The use of exosomes to relieve skin injuries has received considerable attention. The PluronicF-127 hydrogel (PF-127 hydrogel) is a novel biomaterial that can be used to carry biomolecules. This study sought to investigate the impact of exosomes originating from human mesenchymal stem cells (MSCs) developed from adipose tissue (hADSC-Exos) combined with a PF-127 hydrogel on tissue repair and explore the underlying mechanism using in vitro and in vivo experiments. miR-148a-3p is the most expressed microRNA (miRNA) in hADSC-Exos. We found that exosomes combined with the PF-127 hydrogel had a better efficacy than exosomes alone; moreover, miR-148a-3p knockdown lowered its efficacy. In vitro, we observed a significant increase in the tumor-like ability of HUVECs after exosome treatment, which was attenuated after miR-148a-3p knockdown. Furthermore, the effects of miR-148a-3p on hADSC-Exos were achieved through the prevention of PTEN and the triggering of phosphatidylinositol 3-kinase (PI3K)/Akt signaling. In conclusion, our results demonstrated that hADSC-Exos can promote angiogenesis and skin wound healing by delivering miR-148a-3p and have a better effect when combined with the PF-127 hydrogel, which may be an alternative strategy to promote wound healing.

Puerarin Induces Macrophage M2 Polarization to Exert Antinonalcoholic Steatohepatitis Pharmacological Activity via the Activation of Autophagy

To determine the protective mechanism of puerarin against nonalcoholic steatohepatitis (NASH), the pharmacodynamic effects of puerarin on NASH were evaluated by using zebrafish, cells, and mice. Western blotting, flow cytometry, immunofluorescence, and qRT-PCR were used to detect the effects of puerarin on RAW264.7 autophagy and polarization. Key target interactions between autophagy and polarization were detected using immunoprecipitation. Puerarin regulated the M1/M2 ratio of RAW 264.7 cells induced by LPS + INF-γ. Transcriptomics revealed that PAI-1 is a key target of puerarin in regulating macrophage polarization. PAI-1 knockout reduced the number of M1-type macrophages and increased the number of M2-type macrophages. Puerarin regulated PAI-1 and was associated with macrophage autophagy. It increased p-ULK1 expression in macrophages and activated autophagic flux, reducing the level of PAI-1 expression. Stat3/Hif-1α and PI3K/AKT signaling pathways regulated the number of macrophage polarization phenotypes, reducing liver lipid droplet formation, alleviating liver structural abnormalities, decreasing the number of cytoplasmic vacuoles, and decreasing the area of blue collagen in NASH mice. Puerarin is a promising dietary component for NASH alleviation.

Immune cell balance as potential biomarker of progressing non-alcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a widespread chronic, slowly progressive metabolic multifactorial disease. It is represented by several clinical and morphological forms: steatosis, nonalcoholic steatohepatitis (NASH) (with or without fibrosis), and liver cirrhosis. The search for minimally invasive and cost-effective biomarkers of NAFLD is a key task in the diagnosis, staging of progression, and long-term monitoring of NAFLD. This article discusses the possibility of using immune cell balance as potential minimally invasive peripheral markers of NAFLD progression. In the progression of NASH from steatosis to fibrosis and cirrhosis, inflammation plays an important role because of the activation of Kupffer cells and increased migration of monocytes, dendritic cells, neutrophils, and activated T lymphocytes into the tissues. Macrophages originating from monocytes, with NASH progression, gradually begin to prevail over the pool of resident macrophages. The risk of NASH and fibrosis development in patients with NAFLD increases with the ratio of neutrophils/lymphocytes in the liver. An increase in the Th17 cell count and a decrease in T-regulatory cell count can contribute to increased hepatic steatosis and inflammation development in NAFLD and accelerate the transition from simple steatosis to steatohepatitis and fibrosis. Information on the participation of noncoding RNAs in the regulation of the balance of immune cells in NAFLD is presented, which also allows us to consider them as additional, along with cellular, markers of disease progression.

The dynamics of microRNAs level associated with pathological venous angiogenesis in experimental toxic liver fibrosis in rats

BACKGROUND: It is known that miRNAs are important in liver fibrogenesis. However, their use as targets for early diagnosis and treatment of fibrosis is far from use in clinical practice. Angiogenesis and sinusoid capillarization are important histological features of the process. Studies regarding the role of miRNAs in pathological angiogenesis and sinusoid capillarization are insufficient. AIM: To study the molecular targets (miRNAs and mRNAs) dynamics of associated with pathological angiogenesis in toxic fibrosis of the liver; to evaluate the relationship of the selected molecular factors to the processes of restructuring the intrahepatic vascular system. METHODS: Fibrosis and subsequent cirrhosis of the liver in rats of the Wistar line (males) were induced for 17 weeks by a freshly prepared solution of thioacetamide. The level of miRNA-19а-3р, miRNA-29b-3р, miRNA-29b-1-5p, miRNA-34b-5р, miRNA-125b-5р, miRNA-130a-5p, miRNA-195-5р, miRNA-449а-5р, miRNA-449с-5р, miRNA-466d, miRNA-489-3р, miRNA-495, miRNA-664-3р, miRNA-3085, miRNA-3558-3р in fresh frozen liver samples, was determined by Two-tailed RT-qPCR. RESULTS: In this study, we found that throughout the experiment, the relative level of microRNAs varied in a wide range of values (10–3–104 rel. units). In most cases, it decreased at the point of transition from fibrosis to cirrhosis, while growth was observed only for microRNA-29b-3p. Statistically significant correlation relationships were established between microRNAs and the number of interlobular veins, interlobular arteries, sinusoids, and the area of connective tissue (p 0.05). CONCLUSION: A joint analysis of morphological and molecular-genetic parameters allowed us to suggest that within the framework of the current experimental model of liver fibrosis and cirrhosis, the restructuring of the intrahepatic vascular bed and the progression of fibrosis are associated with the dynamics of the level of a number of microRNAs that we studied and Ang mRNA level.

[Influences and mechanism of extracellular vesicles from dermal papilla cells of mice on human hypertrophic scar fibroblasts]

Objective: To investigate the influences and mechanism of extracellular vesicles from dermal papilla cells (DPC-EVs) of mice on human hypertrophic scar fibroblasts (HSFs). Methods: The study was an experimental research. The primary dermal papilla cells (DPCs) of whiskers were extracted from 10 6-week-old male C57BL/6J mice and identified successfully. The DPC-EVs were extracted from the 3rd to 5th passage DPCs by ultracentrifugation, and the morphology was observed through transmission electron microscope and the particle diameter was detected by nanoparticle tracking analyzer (n=3) at 24 h after culture. The 3rd passage of HSFs were divided into DPC-EV group and phosphate buffer solution (PBS) group, which were cultured with DPC-EVs and PBS, respectively. The cell scratch test was performed and cell migration rate at 24 h after scratching was calculated (n=5). The cell proliferation levels at 0 (after 12 h of starvation treatment and before adding DPC-EVs or PBS), 24, 48, 72, and 96 h after culture were detected by using cell counting kit 8 (n=4). The protein expressions of α-smooth muscle actin (α-SMA) and collagen typeⅠ (ColⅠ) in cells at 24 h after culture were detected by immunofluorescence method and Western blotting, and the protein expression of Krüppel-like factor 4 (KLF4) in cells at 24 h after culture was detected by Western blotting. After the 3rd passage of HSFs were cultured with DPC-EVs for 24 h, the cells were divided into blank control group, KLF4 knockdown group, and KLF4 overexpression group according to the random number table. The cells in blank control group were only routinely cultured for 48 h. The cells in KLF4 knockdown group and KLF4 overexpression group were incubated with KLF4 knockdown virus for 24 h, then the cells in KLF4 knockdown group were routinely cultured for 24 h while the cells in KLF4 overexpression group were incubated with KLF4 overexpression virus for 24 h. The protein expressions of KLF4, α-SMA, and ColⅠ in cells were detected by Western blotting at 48 h after culture. Results: At 24 h after culture, the extracted DPC-EVs showed vesicular structure with an average particle diameter of 108.8 nm. At 24 h after scratching, the migration rate of HSFs in PBS group was (54±10)%, which was significantly higher than (29±8)% in DPC-EV group (t=4.37, P<0.05). At 48, 72, and 96 h after culture, the proliferation levels of HSFs in DPC-EV group were significantly lower than those in PBS group (with t values of 4.06, 5.76, and 6.41, respectively, P<0.05). At 24 h after culture, the protein expressions of α-SMA and ColⅠ of HSFs in DPC-EV group were significantly lower than those in PBS group, while the protein expression of KLF4 was significantly higher than that in PBS group. At 48 h after culture, compared with those in blank control group, the protein expression of KLF4 of HSFs in KLF4 knockdown group was down-regulated, while the protein expressions of α-SMA and ColⅠ were both up-regulated; compared with those in KLF4 knockdown group, the protein expression of KLF4 of HSFs in KLF4 overexpression group was up-regulated, while the protein expressions of ColⅠ and α-SMA were down-regulated. Conclusions: The DPC-EVs of mice can inhibit the proliferation and migration of human HSFs and significantly inhibit the expressions of fibrosis markers α-SMA and ColⅠ in human HSFs by activating KLF4.

Regulation Mechanisms and Maintenance Strategies of Stemness in Mesenchymal Stem Cells

Stemness pertains to the intrinsic ability of mesenchymal stem cells (MSCs) to undergo self-renewal and differentiate into multiple lineages, while simultaneously impeding their differentiation and preserving crucial differentiating genes in a state of quiescence and equilibrium. Owing to their favorable attributes, including uncomplicated isolation protocols, ethical compliance, and ease of procurement, MSCs have become a focal point of inquiry in the domains of regenerative medicine and tissue engineering. As age increases or ex vivo cultivation is prolonged, the functionality of MSCs decreases and their stemness gradually diminishes, thereby limiting their potential therapeutic applications. Despite the existence of several uncertainties surrounding the comprehension of MSC stemness, considerable advancements have been achieved in the clarification of the potential mechanisms that lead to stemness loss, as well as the associated strategies for stemness maintenance. This comprehensive review provides a systematic overview of the factors influencing the preservation of MSC stemness, the molecular mechanisms governing it, the strategies for its maintenance, and the therapeutic potential associated with stemness. Finally, we underscore the obstacles and prospective avenues in present investigations, providing innovative perspectives and opportunities for the preservation and therapeutic utilization of MSC stemness.

Strategies to improve the therapeutic efficacy of mesenchymal stem cell-derived extracellular vesicle (MSC-EV): a promising cell-free therapy for liver disease

Liver disease has emerged as a significant worldwide health challenge due to its diverse causative factors and therapeutic complexities. The majority of liver diseases ultimately progress to end-stage liver disease and liver transplantation remains the only effective therapy with the limitations of donor organ shortage, lifelong immunosuppressants and expensive treatment costs. Numerous pre-clinical studies have revealed that extracellular vesicles released by mesenchymal stem cells (MSC-EV) exhibited considerable potential in treating liver diseases. Although natural MSC-EV has many potential advantages, some characteristics of MSC-EV, such as heterogeneity, uneven therapeutic effect, and rapid clearance in vivo constrain its clinical translation. In recent years, researchers have explored plenty of ways to improve the therapeutic efficacy and rotation rate of MSC-EV in the treatment of liver disease. In this review, we summarized current strategies to enhance the therapeutic potency of MSC-EV, mainly including optimization culture conditions in MSC or modifications of MSC-EV, aiming to facilitate the development and clinical application of MSC-EV in treating liver disease.

Innovative preconditioning strategies for improving the therapeutic efficacy of extracellular vesicles derived from mesenchymal stem cells in gastrointestinal diseases

Gastrointestinal (GI) diseases have become a global health issue and an economic burden due to their wide distribution, late prognosis, and the inefficacy of recent available medications. Therefore, it is crucial to search for new strategies for their management. In the recent decades, mesenchymal stem cells (MSCs) therapy has attracted attention as a viable option for treating a myriad of GI disorders such as hepatic fibrosis (HF), ulcerative colitis (UC), acute liver injury (ALI), and non-alcoholic fatty liver disease (NAFLD) due to their regenerative and paracrine properties. Importantly, recent studies have shown that MSC-derived extracellular vesicles (MSC-EVs) are responsible for most of the therapeutic effects of MSCs. In addition, EVs have revealed several benefits over their parent MSCs, such as being less immunogenic, having a lower risk of tumour formation, being able to cross biological barriers, and being easier to store. MSC-EVs exhibited regenerative, anti-oxidant, anti-inflammatory, anti-apoptotic, and anti-fibrotic effects in different experimental models of GI diseases. However, a key issue with their clinical application is the maintenance of their stability and efficacy following in vivo transplantation. Preconditioning of MSC-EVs or their parent cells is one of the novel methods used to improve their effectiveness and stability. Herein, we discuss the application of MSC-EVs in several GI disorders taking into account their mechanism of action. We also summarise the challenges and restrictions that need to be overcome to promote their clinical application in the treatment of various GI diseases as well as the recent developments to improve their effectiveness. A representation of the innovative preconditioning techniques that have been suggested for improving the therapeutic efficacy of MSC-EVs in GI diseases. The pathological conditions in various GI disorders (ALI, UC, HF and NAFLD) create a harsh environment for EVs and their parents, increasing the risk of apoptosis and senescence of MSCs and thereby diminishing MSC-EVs yield and restricting their large-scale applications. Preconditioning with pharmacological agents or biological mediators can improve the therapeutic efficacy of MSC-EVs through their adaption to the lethal environment to which they are subjected. This can result in establishment of a more conducive environment and activation of numerous vital trajectories that act to improve the immunomodulatory, reparative and regenerative activities of the derived EVs, as a part of MSCs paracrine system. ALI, acute liver injury; GI diseases, gastrointestinal diseases; HF, hepatic fibrosis; HSP, heat shock protein; miRNA, microRNA; mRNA, messenger RNA; MSC-EVs, mesenchymal stem cell-derived extracellular vesicles; NAFLD, non-alcoholic fatty liver disease; UC, ulcerative colitis.

Exosomal miR-192-5p secreted by bone marrow mesenchymal stem cells inhibits hepatic stellate cell activation and targets PPP2R3A

Bone marrow mesenchymal stem cell (BSMC)-derived extracellular vehicles (EVs) have a pivotal therapeutic potential in hepatic fibrosis (HF). Activation of hepatic stellate cells (HSCs) is the key mechanism in HF progression. Downregulation of miR-192-5p was previously observed in activated HSCs. Nonetheless, the functions of BSMC-derived exosomal miR-192-5p in activated HSCs remain unclear. In this study, transforming growth factor (TGF)-β1 was used to activate HSC-T6 cells to mimic HF in vitro. Characterization of BMSCs and BMSC-derived EVs was performed. Cell-counting kit-8 assay, flow cytometry, and western blotting revealed that TGF-β1 increased cell viability, promoted cell cycle progression, and induced upregulation of fibrosis markers in HSC-T6 cells. Overexpression of miR-192-5p or BMSC-derived exosomal miR-192-5p suppressed TGF-β1-triggered HSC-T6 cell activation. RT-qPCR revealed that protein phosphatase 2 regulatory subunit B'' alpha (PPP2R3A) was downregulated in miR-192-5p-overexpressed HSC-T6 cells. Luciferase reporter assay was used for verifying the relation between miR-192-5p and PPP2R3A, which showed that miR-192-5p targeted PPP2R3A in activated HSC-T6 cells. Collectively, BMSC-derived exosomal miR-192-5p targets PPP2R3A and inhibits activation of HSC-T6 cells.

Exosome-associated miRNA-99a-5p targeting BMPR2 promotes hepatocyte apoptosis during the process of hepatic fibrosis

Liver fibrosis is a serious stage of chronic liver injury. Inhibition of hepatic stellate cells activation and hepatocytes apoptosis is important measures in the treatment of liver fibrosis. Studies have shown that exosomes are involved in regulating the information transmission between cells, but there are few studies on the interaction between exosomes from HSC and hepatocytes. This study screened miRNAs with significant differences related to liver fibrosis in the database. Then, we activated HSC applying transforming growth factor β1 (TGF-β1) and collected exosomes. The expression of miRNA in HSC-derived exosomes was verified by quantitative real-time PCR (qRT-PCR). The results of cell function test showed that HSC-derived exocrine miRNA-99a-5p could inhibit hepatocytes proliferation and promote hepatocytes apoptosis. Conversely, inhibition of miRNA-99a-5p can promote hepatocytes proliferation and inhibit apoptosis. Target gene prediction and luciferase assay show that miRNA can specifically bind to BMPR2 site sequence. In addition, we also detected the expression of BMPR2 and apoptosis-related protein by qRT-PCR and Western blot (WB). In conclusion, this study demonstrates that HSC-derived exocrine miRNA-99a-5p can promote hepatocytes apoptosis and participate in the process of liver fibrosis by targeting BMPR2. Our findings highlight the therapeutic potential of HSC-derived exocrine miRNA-99a-5p in hepatic fibrosis.

Unveiling Mesenchymal Stem Cells' Regenerative Potential in Clinical Applications: Insights in miRNA and lncRNA Implications

It is now widely recognized that mesenchymal stem cells (MSCs) possess the capacity to differentiate into a wide array of cell types. Numerous studies have identified the role of lncRNA in the regulation of MSC differentiation. It is important to elucidate the role and interplay of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) in the regulation of signalling pathways that govern MSC function. Furthermore, miRNAs and lncRNAs are important clinical for innovative strategies aimed at addressing a wide spectrum of existing and emerging disease. Hence it is important to consider their impact on MSC function and differentiation. Examining the data available in public databases, we have collected the literature containing the latest discoveries pertaining to human stem cells and their potential in both fundamental research and clinical applications. Furthermore, we have compiled completed clinical studies that revolve around the application of MSCs, shedding light on the opportunities presented by harnessing the regulatory potential of miRNAs and lncRNAs. This exploration of the therapeutic possibilities offered by miRNAs and lncRNAs within MSCs unveils exciting prospects for the development of precision therapies and personalized treatment approaches. Ultimately, these advancements promise to augment the efficacy of regenerative strategies and produce positive outcomes for patients. As research in this field continues to evolve, it is imperative to explore and exploit the vast potential of miRNAs and lncRNAs as therapeutic agents. The findings provide a solid basis for ongoing investigations, fuelling the quest to fully unlock the regenerative potential of MSCs.

Advances in Mesenchymal stem cells regulating macrophage polarization and treatment of sepsis-induced liver injury

Sepsis is a syndrome of dysregulated host response caused by infection, which leads to life-threatening organ dysfunction. It is a familiar reason of death in critically ill patients. Liver injury frequently occurs in septic patients, yet the development of targeted and effective treatment strategies remains a pressing challenge. Macrophages are essential parts of immunity system. M1 macrophages drive inflammation, whereas M2 macrophages possess anti-inflammatory properties and contribute to tissue repair processes. Mesenchymal stem cells (MSCs), known for their remarkable attributes including homing capabilities, immunomodulation, anti-inflammatory effects, and tissue regeneration potential, hold promise in enhancing the prognosis of sepsis-induced liver injury by harmonizing the delicate balance of M1/M2 macrophage polarization. This review discusses the mechanisms by which MSCs regulate macrophage polarization, alongside the signaling pathways involved, providing an idea for innovative directions in the treatment of sepsis-induced liver injury.

Function and biomedical implications of exosomal microRNAs delivered by parenchymal and nonparenchymal cells in hepatocellular carcinoma

Small extracellular vesicles (exosomes) are important components of the tumor microenvironment. They are small membrane-bound vesicles derived from almost all cell types and play an important role in intercellular communication. Exosomes transmit biological molecules obtained from parent cells, such as proteins, lipids, and nucleic acids, and are involved in cancer development. MicroRNAs (miRNAs), the most abundant contents in exosomes, are selectively packaged into exosomes to carry out their biological functions. Recent studies have revealed that exosome-delivered miRNAs play crucial roles in the tumorigenesis, progression, and drug resistance of hepatocellular carcinoma (HCC). In addition, exosomes have great industrial prospects in the diagnosis, treatment, and prognosis of patients with HCC. This review summarized the composition and function of exosomal miRNAs of different cell origins in HCC and highlighted the association between exosomal miRNAs from stromal cells and immune cells in the tumor microenvironment and the progression of HCC. Finally, we described the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC.

Placenta mesenchymal stem cell-derived extracellular vesicles alleviate liver fibrosis by inactivating hepatic stellate cells through a miR-378c/SKP2 axis

BACKGROUND

Extracellular vesicles derived from mesenchymal stem/stromal cells (MSCs) have shown therapeutic effects on liver fibrosis. This study aimed to evaluate the effects of extracellular vesicles from placenta-derived MSCs (Pd-MSCs-EVs) on liver fibrosis at 3D/2D levels and explore the potential mechanisms.

METHODS

The multicellular liver organoids, consisting of hepatocytes, hepatic stellate cells (HSCs), Kupffer cells, and liver sinusoidal endothelial cells, were observed for growth status, morphological changes, and metabolism. Human transformation growth factor- beta 1 (TGF-β1) was used to induce fibrosis at optimal concentration. The anti-fibrosis effects of Pd-MSCs-EVs were evaluated in liver organoids and HSCs models. Anti-fibrotic content of Pd-MSCs-EVs was identified by multiple experimental validations.

RESULTS

TGF-β1 induced fibrosis in liver organoids, while Pd-MSCs-EVs significantly alleviated fibrotic phenotypes. Following serial verifications, miR-378c was identified as a potential key anti-fibrosis content. In contrast, miR-378c depletion decreased the anti-fibrotic effects of Pd-MSCs-EVs. Additionally, Pd-MSCs-EVs administration repressed TGF-β1-mediated HSCs activation at 2D or 3D levels. Mechanistically, exosomal miR-378c inactivated HSCs by inhibiting epithelial-mesenchymal transition (EMT) through stabilizing E-cadherin via targeting its E3 ubiquitin ligase S-Phase Kinase Associated Protein 2 (SKP2).

CONCLUSION

Pd-MSCs-EVs ameliorated TGF-β1-induced fibrosis by deactivating HSCs in a miR-378c/SKP2-dependent manner, which may be an efficient therapeutic candidate for liver fibrosis.