Exosomes in liver fibrosis: The role of modulating hepatic stellate cells and immune cells, and prospects for clinical applications

Translational studies of exosomes in sports medicine - a mini-review

This review in sports medicine focuses on the critical role of exosomes in managing chronic conditions and enhancing athletic performance. Exosomes, small vesicles produced by various cells, are essential for cellular communication and transporting molecules like proteins and nucleic acids. Originating from the endoplasmic reticulum, they play a vital role in modulating inflammation and tissue repair. Their significance in sports medicine is increasingly recognized, particularly in healing athletic injuries, improving articular cartilage lesions, and osteoarthritic conditions by modulating cellular behavior and aiding tissue regeneration. Investigations also highlight their potential in boosting athletic performance, especially through myocytes-derived exosomes that may enhance adaptability to physical training. Emphasizing a multidisciplinary approach, this review underlines the need to thoroughly understand exosome biology, including their pathways and classifications, to fully exploit their therapeutic potential. It outlines future directions in sports medicine, focusing on personalized treatments, clinical evaluations, and embracing technological advancements. This research represents a frontier in using exosomes to improve athletes' health and performance capabilities.

Unraveling the Multifaceted Roles of Extracellular Vesicles: Insights into Biology, Pharmacology, and Pharmaceutical Applications for Drug Delivery

Extracellular vesicles (EVs) are nanoparticles released from various cell types that have emerged as powerful new therapeutic option for a variety of diseases. EVs are involved in the transmission of biological signals between cells and in the regulation of a variety of biological processes, highlighting them as potential novel targets/platforms for therapeutics intervention and/or delivery. Therefore, it is necessary to investigate new aspects of EVs' biogenesis, biodistribution, metabolism, and excretion as well as safety/compatibility of both unmodified and engineered EVs upon administration in different pharmaceutical dosage forms and delivery systems. In this review, we summarize the current knowledge of essential physiological and pathological roles of EVs in different organs and organ systems. We provide an overview regarding application of EVs as therapeutic targets, therapeutics, and drug delivery platforms. We also explore various approaches implemented over the years to improve the dosage of specific EV products for different administration routes.

Efficacy and safety of mesenchymal stem cell therapy in liver cirrhosis: a systematic review and meta-analysis

AIM

Although the efficacy and safety of mesenchymal stem cell therapy for liver cirrhosis have been demonstrated in several studies. Clinical cases of mesenchymal stem cell therapy for patients with liver cirrhosis are limited and these studies lack the consistency of treatment effects. This article aimed to systematically investigate the efficacy and safety of mesenchymal stem cells in the treatment of liver cirrhosis.

METHOD

The data source included PubMed/Medline, Web of Science, EMBASE, and Cochrane Library, from inception to May 2023. Literature was screened by the PICOS principle, followed by literature quality evaluation to assess the risk of bias. Finally, the data from each study's outcome indicators were extracted for a combined analysis. Outcome indicators of the assessment included liver functions and adverse events. Statistical analysis was performed using Review Manager 5.4.

RESULTS

A total of 11 clinical trials met the selection criteria. The pooled analysis' findings demonstrated that both primary and secondary indicators had improved. Compared to the control group, infusion of mesenchymal stem cells significantly increased ALB levels in 2 weeks, 1 month, 3 months, and 6 months, and significantly decreased MELD score in 1 month, 2 months, and 6 months, according to a subgroup analysis using a random-effects model. Additionally, the hepatic arterial injection favored improvements in MELD score and ALB levels. Importantly, none of the included studies indicated any severe adverse effects.

CONCLUSION

The results showed that mesenchymal stem cell was effective and safe in the treatment of liver cirrhosis, improving liver function (such as a decrease in MELD score and an increase in ALB levels) in patients with liver cirrhosis and exerting protective effects on complications of liver cirrhosis and the incidence of hepatocellular carcinoma. Although the results of the subgroup analysis were informative for the selection of mesenchymal stem cells for clinical treatment, a large number of high-quality randomized controlled trials validations are still needed.

Liver Fibrosis Resolution: From Molecular Mechanisms to Therapeutic Opportunities

The liver is a critical system for metabolism in human beings, which plays an essential role in an abundance of physiological processes and is vulnerable to endogenous or exogenous injuries. After the damage to the liver, a type of aberrant wound healing response known as liver fibrosis may happen, which can result in an excessive accumulation of extracellular matrix (ECM) and then cause cirrhosis or hepatocellular carcinoma (HCC), seriously endangering human health and causing a great economic burden. However, few effective anti-fibrotic medications are clinically available to treat liver fibrosis. The most efficient approach to liver fibrosis prevention and treatment currently is to eliminate its causes, but this approach's efficiency is too slow, or some causes cannot be fully eliminated, which causes liver fibrosis to worsen. In cases of advanced fibrosis, the only available treatment is liver transplantation. Therefore, new treatments or therapeutic agents need to be explored to stop the further development of early liver fibrosis or to reverse the fibrosis process to achieve liver fibrosis resolution. Understanding the mechanisms that lead to the development of liver fibrosis is necessary to find new therapeutic targets and drugs. The complex process of liver fibrosis is regulated by a variety of cells and cytokines, among which hepatic stellate cells (HSCs) are the essential cells, and their continued activation will lead to further progression of liver fibrosis. It has been found that inhibiting HSC activation, or inducing apoptosis, and inactivating activated hepatic stellate cells (aHSCs) can reverse fibrosis and thus achieve liver fibrosis regression. Hence, this review will concentrate on how HSCs become activated during liver fibrosis, including intercellular interactions and related signaling pathways, as well as targeting HSCs or liver fibrosis signaling pathways to achieve the resolution of liver fibrosis. Finally, new therapeutic compounds targeting liver fibrosis are summarized to provide more options for the therapy of liver fibrosis.

Schizandrin C regulates lipid metabolism and inflammation in liver fibrosis by NF-κB and p38/ERK MAPK signaling pathways

Liver fibrosis is considered a sustained wound healing response and metabolic syndrome, and its therapy is of great significance for chronic liver disease. Schizandrin C, as one lignan from hepatic protectant Schisandra chinensis, can depress the oxidative effect and lipid peroxidation, and protect against liver injury. In this study, C57BL/6J mice were used to estimate a liver fibrosis model by CCl₄, and Schizandrin C exerted an anti-hepatic fibrosis effect, as evidenced by decreased alanine aminotransferase, aspartate aminotransferase and total bilirubin activities in serum, lower hydroxyproline content, recuperative structure and less collagen accumulation in the liver. In addition, Schizandrin C reduced the expressions of alpha-smooth muscle actin and type Ι collagen in the liver. In vitro experiments also revealed that Schizandrin C attenuated hepatic stellate cell activation in both LX-2 and HSC-T6 cells. Furthermore, lipidomics and quantitative real-time PCR analysis revealed that Schizandrin C regulated the lipid profile and related metabolic enzymes in the liver. In addition, the mRNA levels of inflammation factors were downregulated by Schizandrin C treatment, accompanied by lower protein levels of IκB-Kinase-β, nuclear factor kappa-B p65, and phospho-nuclear factor kappa-B p65. Finally, Schizandrin C inhibited the phosphorylation of p38 MAP kinase and extracellular signal-regulated protein kinase, which were activated in the CCl₄ fibrotic liver. Taken together, Schizandrin C can regulate lipid metabolism and inflammation to ameliorate liver fibrosis by nuclear factor kappa-B and p38/ERK MAPK signaling pathways. These findings supported Schizandrin C as a potential drug for liver fibrosis.