ADSCs-derived exosomes ameliorate hepatic fibrosis by suppressing stellate cell activation and remodeling hepatocellular glutamine synthetase-mediated glutamine and ammonia homeostasis

Lipid Nanovesicle Platforms for Hepatocellular Carcinoma Precision Medicine Therapeutics: Progress and Perspectives

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality globally. HCC is highly heterogenous with diverse etiologies leading to different driver mutations potentiating unique tumor immune microenvironments. Current therapeutic options, including immune checkpoint inhibitors and combinations, have achieved limited objective response rates for the majority of patients. Thus, a precision medicine approach is needed to tailor specific treatment options for molecular subsets of HCC patients. Lipid nanovesicle platforms, either liposome- (synthetic) or extracellular vesicle (natural)-derived present are improved drug delivery vehicles which may be modified to contain specific cargos for targeting specific tumor sites, with a natural affinity for liver with limited toxicity. This mini-review provides updates on the applications of novel lipid nanovesicle-based therapeutics for HCC precision medicine and the challenges associated with translating this therapeutic subclass from preclinical models to the clinic.

Dietary fiber alleviates alcoholic liver injury via Bacteroides acidifaciens and subsequent ammonia detoxification

The gut microbiota and diet-induced changes in microbiome composition have been linked to various liver diseases, although the specific microbes and mechanisms remain understudied. Alcohol-related liver disease (ALD) is one such disease with limited therapeutic options due to its complex pathogenesis. We demonstrate that a diet rich in soluble dietary fiber increases the abundance of Bacteroides acidifaciens (B. acidifaciens) and alleviates alcohol-induced liver injury in mice. B. acidifaciens treatment alone ameliorates liver injury through a bile salt hydrolase that generates unconjugated bile acids to activate intestinal farnesoid X receptor (FXR) and its downstream target, fibroblast growth factor-15 (FGF15). FGF15 promotes hepatocyte expression of ornithine aminotransferase (OAT), which facilitates the metabolism of accumulated ornithine in the liver into glutamate, thereby providing sufficient glutamate for ammonia detoxification via the glutamine synthesis pathway. Collectively, these findings uncover a potential therapeutic strategy for ALD involving dietary fiber supplementation and B. acidifaciens.

Single and combined strategies for mesenchymal stem cell exosomes alleviate liver fibrosis: a systematic review and meta-analysis of preclinical animal models

Background: The efficacy of mesenchymal stem cells (MSCs) in treating liver fibrosis has been supported by various clinical studies. However, stem cell transplantation is limited in clinical application due to its low survival rate, low liver implantation rate, and possible carcinogenicity. Recently, there has been increasing interest in the use of MSC-exos due to their widespread availability, low immunogenicity, and non-carcinogenic properties. Numerous studies have demonstrated the potential of MSC-exos in treating liver fibrosis and preventing progression to end-stage liver disease. Objective: This study aimed to systematically investigate the efficacy of MSC-exos single administration in the treatment of hepatic fibrosis and the combined advantages of MSC-exos in combination with drug therapy (MSC-exos-drugs). Methods: Data sources included PubMed, Web of Science, Embase, and the Cochrane Library, which were built up to January 2024. The population, intervention, comparison, outcomes, and study design (PICOS) principle was used to screen the literature, and the quality of the literature was evaluated to assess the risk of bias. Finally, the data from each study's outcome indicators were extracted for a combined analysis. Results: After screening, a total of 18 papers (19 studies) were included, of which 12 involved MSC-exos single administration for the treatment of liver fibrosis and 6 involved MSC-exos-drugs for the treatment of liver fibrosis. Pooled analysis revealed that MSC-exos significantly improved liver function, promoted the repair of damaged liver tissue, and slowed the progression of hepatic fibrosis and that MSC-exos-drugs were more efficacious than MSC-exos single administration. Subgroup analyses revealed that the use of AD-MSC-exos resulted in more consistent and significant efficacy when MSC-exos was used to treat hepatic fibrosis. For MSC-exos-drugs, a more stable end result is obtained by kit extraction. Similarly, infusion through the abdominal cavity is more effective. Conclusion: The results suggest that MSC-exos can effectively treat liver fibrosis and that MSC-exos-drugs are more effective than MSC-exos single administration. Although the results of the subgroup analyses provide recommendations for clinical treatment, a large number of high-quality experimental validations are still needed. Systematic Review Registration: CRD42024516199.

Potential Consequences of the Use of Adipose-Derived Stem Cells in the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) ranks as the most prevalent of primary liver cancers and stands as the third leading cause of cancer-related deaths. Early-stage HCC can be effectively managed with available treatment modalities ranging from invasive techniques, such as liver resection and thermoablation, to systemic therapies primarily employing tyrosine kinase inhibitors. Unfortunately, these interventions take a significant toll on the body, either through physical trauma or the adverse effects of pharmacotherapy. Consequently, there is an understandable drive to develop novel HCC therapies. Adipose-derived stem cells (ADSCs) are a promising therapeutic tool. Their facile extraction process, coupled with the distinctive immunomodulatory capabilities of their secretome, make them an intriguing subject for investigation in both oncology and regenerative medicine. The factors they produce are both enzymes affecting the extracellular matrix (specifically, metalloproteinases and their inhibitors) as well as cytokines and growth factors affecting cell proliferation and invasiveness. So far, the interactions observed with various cancer cell types have not led to clear conclusions. The evidence shows both inhibitory and stimulatory effects on tumor growth. Notably, these effects appear to be dependent on the tumor type, prompting speculation regarding their potential inhibitory impact on HCC. This review briefly synthesizes findings from preclinical and clinical studies examining the effects of ADSCs on cancers, with a specific focus on HCC, and emphasizes the need for further research.

The miR-23b-3p from adipose-derived stem cell exosomes alleviate inflammation in mice experiencing kainic acid-induced epileptic seizures

Epilepsy is a common neurologic disorder. While a good clinical solution is still missing, studies have confirmed that exosomes (Exos) derived from adipose-derived stem cells (ADSCs) had a therapeutic effect on various diseases, including neurological diseases. Therefore, this study aimed to reveal whether ADSC-Exo treatment could improve kainic acid (KA)-induced seizures in epileptic mice. ADSCs and Exos were isolated. Mice were generated with KA-induced epileptic seizures. ELISA was used to detect inflammatory factor expression. Luciferase reporter analysis detection showed a relationship among miR-23b-3p, STAT1, and glyoxylate reductase 1 (GlyR1). ADSC-Exos had a protective effect on KA-induced seizures by inhibiting inflammatory factor expression and the M1 microglia phenotype. The result showed that miR-23b-3p played an important role in the Exo-mediated protective effect in KA-induced seizures in epileptic mice by regulating STAT1 and GlyR1. Luciferase reporter analysis confirmed that miR-23b-3p interacted with the 3'-UTR of STAT1 and GlyR1. The miR-23b-3p inhibited M1 microglia-mediated inflammatory factor expression in microglial cells by regulating STAT1 and GlyR1. The downregulation of miR-23b-3p decreased the protective effect of ADSC-Exos on KA-induced seizures in epileptic mice. The miR-23b-3p from ADSC-Exos alleviated inflammation in mice with KA-induced epileptic seizures.

Label-free proteomic analysis reveals the hepatoprotective mechanism of gypenosides in liver injury rats

Chronic liver disease, a long-term condition resulting from various causes such as alcohol abuse, metabolic disorders, and viral hepatitis, is becoming a significant global health challenge. Gypenosides (GPs), derived from the traditional Chinese medicine Gynostemma pentaphyllum (Thunb.) Makino, exhibited hepatoprotective properties in recent years, yet the precise therapeutic mechanism remains unclear. In this study, label-free and parallel reaction monitoring (PRM) proteomics were used to elucidate the hepatoprotective mechanism of GPs in liver injury rats. Through label-free proteomics, we identified 2104 differentially expressed proteins (DEPs) associated with liver injury, along with 1974 DEPs related to the effects of GPs. Bioinformatics analysis revealed that GPs primarily restored metabolic processes involving valine, leucine, and isoleucine degradation, as well as propanoate and butanoate metabolism, and steroid hormone biosynthesis during liver injury. Subsequently, overlapping the two groups of DEPs identified 1508 proteins reversed following GPs treatment, with key targets further validated by PRM. Eight target proteins were identified for GPs treatment of liver injury, including Lgals3, Psat1, Phgdh, Cyp3a9, Cyp2c11, Cyp4a2, Glul, and Ces1d. These findings not only elucidated the hepatoprotective mechanism of GPs, but may also serve as potential therapeutic targets of chronic liver disease.

Adipose-Derived Stem Cell Exosomes Facilitate Diabetic Wound Healing: Mechanisms and Potential Applications

Wound healing in diabetic patients is frequently hampered. Adipose-derived stem cell exosomes (ADSC-eoxs), serving as a crucial mode of intercellular communication, exhibit promising therapeutic roles in facilitating wound healing. This review aims to comprehensively outline the molecular mechanisms through which ADSC-eoxs enhance diabetic wound healing. We emphasize the biologically active molecules released by these exosomes and their involvement in signaling pathways associated with inflammation modulation, cellular proliferation, vascular neogenesis, and other pertinent processes. Additionally, the clinical application prospects of the reported ADSC-eoxs are also deliberated. A thorough understanding of these molecular mechanisms and potential applications is anticipated to furnish a theoretical groundwork for combating diabetic wound healing.

Recent advances in the use of extracellular vesicles from adipose-derived stem cells for regenerative medical therapeutics

Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells (MSCs) isolated from adipose tissue. They possess remarkable properties, including multipotency, self-renewal, and easy clinical availability. ADSCs are also capable of promoting tissue regeneration through the secretion of various cytokines, factors, and extracellular vesicles (EVs). ADSC-derived EVs (ADSC-EVs) act as intercellular signaling mediators that encapsulate a range of biomolecules. These EVs have been found to mediate the therapeutic activities of donor cells by promoting the proliferation and migration of effector cells, facilitating angiogenesis, modulating immunity, and performing other specific functions in different tissues. Compared to the donor cells themselves, ADSC-EVs offer advantages such as fewer safety concerns and more convenient transportation and storage for clinical application. As a result, these EVs have received significant attention as cell-free therapeutic agents with potential future application in regenerative medicine. In this review, we focus on recent research progress regarding regenerative medical use of ADSC-EVs across various medical conditions, including wound healing, chronic limb ischemia, angiogenesis, myocardial infarction, diabetic nephropathy, fat graft survival, bone regeneration, cartilage regeneration, tendinopathy and tendon healing, peripheral nerve regeneration, and acute lung injury, among others. We also discuss the underlying mechanisms responsible for inducing these therapeutic effects. We believe that deciphering the biological properties, therapeutic effects, and underlying mechanisms associated with ADSC-EVs will provide a foundation for developing a novel therapeutic approach in regenerative medicine.

Influence of the glutamate-glutamine cycle on valproic acid-associated hepatotoxicity in pediatric patients with epilepsy

INTRODUCTION

Although valproic acid is generally well tolerated, hepatotoxicity is a common side effect in patients receiving long-term treatment. However, the mechanisms underlying valproic acid-associated hepatotoxicity remain elusive.

METHODS

To investigate the mechanisms and explore the potential risk factors for valproic acid-associated hepatotoxicity, 165 age-matched pediatric patients were recruited for laboratory tests and glutamate-glutamine cycle analysis.

RESULTS

The concentration of glutamate in patients with hepatotoxicity was significantly greater than that in control patients, while the concentration of glutamine in patients with hepatotoxicity was significantly lower than that in control patients (P <0.05). In addition, the frequencies of the heterozygous with one mutant allele and homozygous with two mutant alleles genotypes in glutamate-ammonia ligase rs10911021 were significantly higher in the hepatotoxicity group than those in the control group (47.1 percent versus 32.5 percent, P = 0.010; 17.6 percent versus 5.2 percent, P = 0.001, respectively). Moreover, heterozygous carriers with one mutant allele and homozygous carriers with two mutant alleles genotypes of glutamate-ammonia ligase rs10911021 exhibited significant differences in the concentrations of glutamine and glutamate concentrations (P ˂ 0.001 and P = 0.001, respectively) and liver function indicators (activities of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase, P <0.001, respectively). Furthermore, logistic regression analysis indicated that glutamate-ammonia ligase rs10911021 (P = 0.002, odds ratio: 3.027, 95 percent confidence interval, 1.521 - 6.023) and glutamate (P = 0.001, odds ratio: 2.235, 95 percent confidence interval, 1.369 - 3.146) were associated with a greater risk for hepatotoxicity, while glutamine concentrations were negatively associated with hepatotoxicity (P = 0.001, odds ratio: 0.711, 95 percent confidence interval, 0.629 - 0.804).

DISCUSSION

Understanding pharmacogenomic risks for valproic acid induced hepatotoxicity might help direct patient specific care. Limitations of our study include the exclusive use of children from one location and concomitant medication use in many patients.

CONCLUSION

Perturbation of the glutamate-glutamine cycle is associated with valproic acid-associated hepatotoxicity. Moreover, glutamate-ammonia ligase rs10911021, glutamate and glutamine concentrations are potential risk factors for valproic acid-associated hepatotoxicity.

Adipose-derived stem cells can alleviate RHDV2 induced acute liver injury in rabbits

Rabbit hemorrhagic disease virus (RHDV) can cause fatal fulminant hepatitis, which is very similar to human acute liver failure. The aim of this study was to investigate whether adipose-derived stem cells (ADSCs) could alleviate RHDV2-induced liver injury in rabbits. Twenty 50-day-old rabbits were divided randomly into two groups (RHDV2 group, ADSCs + RHDV2 group). Starting from the 1st day, two groups of rabbits were given 0.5 ml of viral suspensions by subcutaneous injection in the neck. Meanwhile, the ADSCs + RHDV2 group was injected with ADSCs cell suspension (1.5 × 107 cells/ml) via a marginal ear vein, and the RHDV2 group was injected with an equal amount of saline via a marginal ear vein. At the end of the 48 h experiment, the animals were euthanized and gross hepatic changes were observed before liver specimens were collected. Histopathological analysis was performed using hematoxylin-eosin (HE), periodic acid schiff (PAS) and Masson's trichrome staining. For RHDV2 affected rabbits, HE staining demonstrated disorganized hepatic cords, loss of cellular detail, and severe cytoplasmic vacuolation within hepatocytes. Glycogen was not observed with PAS staining, and Masson's Trichrome staining showed increased hepatic collagen deposition. For rabbits treated with ADSCs at the time of inoculation, hepatic pathological changes were significantly less severe, liver glycogen synthesis was increased, and collagen fiber deposition was decreased. For RHDV2 affected rabbits, Tunel and immunofluorescence staining showed that the number of apoptotic cells, TGF-β, and MMP-9 protein expression increased. And that in the ADSC treated group there was less hepatocyte apoptosis. In addition, RHDV2 induces liver inflammation and promotes the expression of IL-1β, IL-6, and TNF-α. In rabbits administered ADSCs at time of inoculation, the expression of inflammatory factors in liver tissue decreased significantly. Our experiments show that ADSCs can protect rabbits from liver injury by RHDV2 and reduce the pathological and inflammatory response of liver. However, the specific protective mechanism needs further study.

Adipose tissue-derived stem cells, in vivo and in vitro models for metabolic diseases

The primary role of adipose tissue stem cells (ADSCs) is to support the function and homeostasis of adipose tissue in physiological and pathophysiological conditions. However, when ADSCs become dysfunctional in diseases such as obesity and cancer, they become impaired, undergo signalling changes, and their epigenome is altered, which can have a dramatic effect on human health. In more recent years, the therapeutic potential of ADSCs in regenerative medicine, wound healing, and for treating conditions such as cancer and metabolic diseases has been extensively investigated with very promising results. ADSCs have also been used to generate two-dimensional (2D) and three-dimensional (3D) cellular and in vivo models to study adipose tissue biology and function as well as intracellular communication. Characterising the biology and function of ADSCs, how it is altered in health and disease, and its therapeutic potential and uses in cellular models is key for designing intervention strategies for complex metabolic diseases and cancer.

Therapeutic potential of ADSC-EV-derived lncRNA DLEU2: A novel molecular pathway in alleviating sepsis-induced lung injury via the miR-106a-5p/LXN axis

This study investigates the molecular mechanisms by which extracellular vesicles (EVs) derived from adipose-derived mesenchymal stem cells (ADSCs) promote M2 polarization of macrophages and thus reduce lung injury caused by sepsis. High-throughput sequencing was used to identify differentially expressed genes related to long non-coding RNA (lncRNA) in ADSC-derived EVs (ADSC-EVs) in sepsis lung tissue. Weighted gene co-expression network analysis (WGCNA) was employed to predict the downstream target genes of the lncRNA DLEU2. The RNAInter database predicted miRNAs that interact with DLEU2 and LXN. Functional and pathway enrichment analyses were performed using GO and KEGG analysis. A mouse model of sepsis was established, and treatment with a placebo or ADSC-EVs was administered, followed by RT-qPCR analysis. ADSC-EVs were isolated and identified. In vitro cell experiments were conducted using the mouse lung epithelial cell line MLE-12, mouse macrophage cell line RAW264.7, and mouse lung epithelial cell line (LEPC). ADSC-EVs were co-cultured with RAW264.7 and MLE-12/LEPC cells to study the regulatory mechanism of the lncRNA DLEU2. Cell viability, proliferation, and apoptosis of lung injury cells were assessed using CCK-8, EdU, and flow cytometry. ELISA was used to measure the levels of inflammatory cytokines in the sepsis mouse model, flow cytometry was performed to determine the number of M1 and M2 macrophages, lung tissue pathology was evaluated by H&E staining, and immunohistochemistry was conducted to examine the expression of proliferation- and apoptosis-related proteins. High-throughput sequencing and bioinformatics analysis revealed enrichment of the lncRNA DLEU2 in ADSC-EVs in sepsis lung tissue. Animal and in vitro cell experiments showed increased expression of the lncRNA DLEU2 in sepsis lung tissue after treatment with ADSC-EVs. Furthermore, ADSC-EVs were found to transfer the lncRNA DLEU2 to macrophages, promoting M2 polarization, reducing inflammation response in lung injury cells, and enhancing their viability, proliferation, and apoptosis inhibition. Further functional experiments indicated that lncRNA DLEU2 promotes M2 polarization of macrophages by regulating miR-106a-5p/LXN, thereby enhancing the viability and proliferation of lung injury cells and inhibiting apoptosis. Overexpression of miR-106a-5p could reverse the biological effects of ADSC-EVs-DLEU2 on MLE-12 and LEPC in vitro cell models. Lastly, in vivo animal experiments confirmed that ADSC-EVs-DLEU2 promotes high expression of LXN by inhibiting the expression of miR-106a-5p, further facilitating M2 macrophage polarization and reducing lung edema, thus alleviating sepsis-induced lung injury. lncRNA DLEU2 in ADSC-EVs may promote M2 polarization of macrophages and enhance the viability and proliferation of lung injury cells while inhibiting inflammation and apoptosis reactions, thus ameliorating sepsis-induced lung injury in a mechanism involving the regulation of the miR-106a-5p/LXN axis.

Dysbiosis of gut microbiota and metabolites is associated with radiation-induced colorectal fibrosis and is restored by adipose-derived mesenchymal stem cell therapy

AIMS

This study aimed to investigate the effects of adipose-derived mesenchymal stem cells (ADSCs) on radiation-induced colorectal fibrosis (RICF) along with the associated dysbiosis of gut microbiota and metabolites.

MAIN METHODS

Fecal microbiota were assessed through 16S rRNA gene sequencing, and the fecal metabolome was characterized using liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry. The correlation between microbiota and metabolome data was explored.

KEY FINDINGS

ADSC injection demonstrated a significant restoration of radiation-induced intestinal damage in vivo. At the phylum level, irradiated rats exhibited an increase in Bacteroidota and Campilobacterota, and a decrease in Firmicutes and Desulfobacterota, contrasting with the ADSC treatment group. Metabolomic analysis revealed 72 differently expressed metabolites (DEMs) from gas chromatography-mass spectrometry and 284 DEMs from liquid chromatography-mass spectrometry in the radiation group compared to the blank group. In the ADSC treatment group versus the radiation group, 36 DEMs from gas chromatography-mass spectrometry and 341 DEMs from liquid chromatography-mass spectrometry were identified. KEGG enrichment analysis implicated pathways such as steroid hormone biosynthesis, gap junction, primary bile acid biosynthesis, citrate cycle, cAMP signaling pathway, and alanine, aspartate, and glutamate metabolism during RICF progression and after treated with ADSCs. Correlation analysis highlighted the role of ADSCs in modulating the metabolic process of Camelledionol in fecal Bacteroides.

SIGNIFICANCE

These findings underscore the potential of ADSCs in reversing dysbiosis and restoring normal colonic flora in the context of RICF, offering valuable insights for therapeutic interventions targeting radiation-induced complications.

ADSC-Exos enhance functional recovery after spinal cord injury by inhibiting ferroptosis and promoting the survival and function of endothelial cells through the NRF2/SLC7A11/GPX4 pathway

BACKGROUND

Spinal cord injury (SCI) is a devastating disease that causes major motor, sensory and autonomic dysfunctions. Currently, there is a lack of effective treatment. In this study, we aimed to investigate the potential mechanisms of Exosomes from adipose-derived stem cells (ADSC-Exos) in reducing ferroptosis and promoting angiogenesis after spinal cord injury.

METHODS

We isolated ADSC-Exos, the characteristics of which were confirmed. In vitro, we tested the potential of ADSC-Exos to promote the survival and function of human brain microvascular endothelial cells (HBMECs) and analyzed the ferroptosis of HBMECs. In vivo, we established rat models of SCI and locally injected ADSC-Exos to verify their efficacy.

RESULTS

ADSC-Exos can reduce reactive oxygen species (ROS) accumulation and cell damage induced by an excessive inflammatory response in HBMECs. ADSC-Exos inhibit ferroptosis induced by excessive inflammation and upregulate the expression of glutathione peroxidase 4(GPX4) in HBMECs. It can also effectively promote proliferation, migration, and vessel-like structure formation. In vitro, ADSC-Exos improved behavioral function after SCI and increased the number and density of blood vessels around the damaged spinal cord. Moreover, we found that ADSC-Exos could increase nuclear factor erythroid-2-related factor 2(NRF2) expression and nuclear translocation, thereby affecting the expression of solute carrier family 7 member 11(SLC7A11) and GPX4, and the NRF2 inhibitor ML385 could reverse the above changes.

CONCLUSION

Our results suggest that ADSC-Exos may inhibit ferroptosis and promote the recovery of vascular and neural functions after SCI through the NRF2/SLC7A11/GPX4 pathway. This may be a potential therapeutic mechanism for spinal cord injury.

Communication between nonalcoholic fatty liver disease and atherosclerosis: Focusing on exosomes

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic hepatic disorder on a global scale. Atherosclerosis (AS), a leading cause of cardiovascular diseases, stands as the primary contributor to mortality among patients diagnosed with NAFLD. However, the precise etiology by which NAFLD causes AS remains unclear. Exosomes are nanoscale extracellular vesicles secreted by cells, and are considered to participate in complex biological processes by promoting cell-to-cell and organ-to-organ communications. As vesicles containing protein, mRNA, non-coding RNA and other bioactive molecules, exosomes can participate in the development of NAFLD and AS respectively. Recently, studies have shown that NAFLD can also promote the development of AS via secreting exosomes. Herein, we summarized the recent advantages of exosomes in the pathogenesis of NAFLD and AS, and highlighted the role of exosomes in mediating the information exchange between NAFLD and AS. Further, we discussed how exosomes play a prominent role in enabling information exchange among diverse organs, delving into a novel avenue for investigating the link between diseases and their associated complications. The future directions and emerging challenges are also listed regarding the exosome-based therapeutic strategies for AS under NAFLD conditions.

Single-cell atlas reveals characteristic changes in intrahepatic HBV-specific leukocytes

IMPORTANCE

Hepatitis B virus (HBV)-specific CD8+ T cells play a central role in the clearance of virus and HBV-related liver injury. Acute infection with HBV induces a vigorous, multifunctional CD8+ T cell response, whereas chronic one exhibits a weaker response. Our study elucidated HBV-specific T cell responses in terms of viral abundance rather than the timing of infection. We showed that in the premalignant stage, the degree of impaired T cell function was not synchronized with the viral surface antigen, which was attributed the liver's tolerance to the virus. However, after the development of hepatocellular carcinoma, T cell exhaustion was inevitable, and it was marked by the exhaustion of the signature transcription factor TOX.

Comparative study between the effect of mesenchymal stem cells microvesicles versus ozone on induced liver injury in adult male albino rats (Histological & Immunohistochemical study)

Liver disease accounts for approximately 2 million deaths er year worldwide. Liver fibrisis results from chronic injury to the liver. If not effectively treated in time, liver fibrosis may transform into liver cirrhosis. MVs are recognized as potential biomarkers and important theraputic tools for a wide sectrum of diseases. Medical ozone has the ability to protect the body against pathological conditions caused by oxidative stress. The influence of ozone and MVs on CCL4 induced liver fibrosis was investigated in this study. Forty-eight adult male albino rats were divided into four equal groups. I control, II CCL4 group, III ozone and IV microvesicles groups. Liver fibrosis was induced in group II, III & IV using 12 SC injections (0.5 ml/kg body weight) of CCL4 dissolved in olive oil twice ber week for weeks. Blood samples were obtained to estimate serum ALT & AST. Liver tissues were processed for measurment of GSH & SOD, light and electron microscopic examination. H&E staine sections og group II showed dilated congested sinusoids and centralveins, mononuclear infiltrations, vacuolations and dark nuclei. Ultrastructurally, group II revealed irregular heterochromatic nuclei of hepatocytes, small scanty mitochondria & vacuolations. Morphometric & statistical analyses were performed. Group III showed some improvement, however, group IV showed more imrovement. The results indicates that MVs caused marked improvement than ozone against CCL4 induced liver damage via antioxidant & antiinflammatory properties.

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.

Exosomes from adipose-derived mesenchymal stem cells improve liver fibrosis by regulating the miR-20a-5p/TGFBR2 axis to affect the p38 MAPK/NF-κB pathway

OBJECTIVE

Human adipose-derived mesenchymal stem cell exosomes (ADSC-Exos) are active constituents for treating liver fibrosis. This paper attempted to preliminarily explain the functional mechanism of ADSC-Exos in liver fibrosis through the p38 MAPK/NF-κB pathway.

METHODS

The cell models of hepatic fibrosis were established by inducing LX-2 cells with TGF-β1. Mouse models of liver fibrosis were established by treating mice with CCl4. The in vivo and in vitro models of liver fibrosis were treated with ADSC-Exos. ADSCs were identified by flow cytometry/Alizarin red/oil red O/alcian blue staining. ADSC-Exos were identified by transmission electron microscopy, nanoparticle tracking analysis, and Western blot. LX-2 cell proliferation/viability were evaluated by MTT/BrdU assays. Exosomes were tracked in vivo and body weight changes in mice were monitored. Hepatic pathological changes were observed by HE/Masson staining. α-SMA/collagen I levels in liver tissues were assessed by immunohistochemistry. HA/PIIINP concentrations were measured using the magnetic particle chemiluminescence method. Liver function was assessed using an automatic analyzer. miR-20a-5p level was measured by RT-qPCR. The mRNA levels of fibrosis markers were determined by RT-qPCR, and their protein levels and levels of MAPK/NF-κB pathway-related proteins, as well as TGFBR2 protein level were measured by Western blot. The P65 nuclear expression in mouse liver tissues was quantified by immunofluorescence.

RESULTS

ADSC-Exos suppressed TGF-β1-induced LX-2 cell proliferation and fibrosis and reduced mRNA and protein levels of fibrosis markers in vitro. ADSC-Exos ameliorated liver fibrosis by inhibiting the p38 MAPK/NF-κB pathway activation. ADSC-Exos inhibited activation of the p38 MAPK/NF-κB pathway via regulating the miR-20a-5p/TGFBR2 axis. The in vivo experiment asserted that ADSC-Exos were mainly distributed in the liver, and ADSC-Exos relieved liver fibrosis in mice, which was evidenced by alleviating decreased body weight, reducing collagen and enhancing liver function, and repressed the activation of the p38 MAPK/NF-κB pathway via the miR-20a-5p/TGFBR2 axis.

CONCLUSION

ADSC-Exos attenuated liver fibrosis by suppressing the activation of the p38 MAPK/NF-κB pathway via the miR-20a-5p/TGFBR2 axis.

Engineering exosomes derived from subcutaneous fat MSCs specially promote cartilage repair as miR-199a-3p delivery vehicles in Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease involving cartilage. Exosomes derived from Mesenchymal stem cells (MSCs) therapy improves articular cartilage repair, but subcutaneous fat (SC) stromal cells derived exosomes (MSCsSC-Exos), especially engineering MSCsSC-Exos for drug delivery have been rarely reported in OA therapy. This objective of this study was to clarify the underlying mechanism of MSCsSC-Exos on cartilage repair and therapy of engineering MSCsSC-Exos for drug delivery in OA. MSCsSC-Exos could ameliorate the pathological severity degree of cartilage via miR-199a-3p, a novel molecular highly enriched in MSCsSC-Exos, which could mediate the mTOR-autophagy pathway in OA rat model. Intra-articular injection of antagomiR-199a-3p dramatically attenuated the protective effect of MSCsSC-Exos-mediated on articular cartilage in vivo. Furthermore, to achieve the superior therapeutic effects of MSCsSC-Exos on injured cartilage, engineering exosomes derived from MSCsSC as the chondrocyte-targeting miR-199a-3p delivery vehicles were investigated in vitro and in vivo. The chondrocyte-binding peptide (CAP) binding MSCsSC-Exos could particularly deliver miR-199a-3p into the chondrocytes in vitro and into deep articular tissues in vivo, then exert the excellent protective effect on injured cartilage in DMM-induced OA mice. As it is feasible to obtain human subcutaneous fat from healthy donors by liposuction operation in clinic, meanwhile engineering MSCsSC-Exos to realize targeted delivery of miR-199a-3p into chondrocytes exerted excellent therapeutic effects in OA animal model in vivo. Through combining MSCsSC-Exos therapy and miRNA therapy via an engineering approach, we develop an efficient MSCsSC-Exos-based strategy for OA therapy and promote the application of targeted-MSCsSC-Exos for drug delivery in the future.

Advances in Immunomodulatory Mechanisms of Mesenchymal Stem Cells-Derived Exosome on Immune Cells in Scar Formation

Pathological scars are the result of over-repair and excessive tissue proliferation of the skin injury. It may cause serious dysfunction, resulting in psychological and physiological burdens on the patients. Currently, mesenchymal stem cells-derived exosomes (MSC-Exo) displayed a promising therapeutic effect on wound repair and scar attenuation. But the regulatory mechanisms are opinions vary. In view of inflammation has long been proven as the initial factor of wound healing and scarring, and the unique immunomodulation mechanism of MSC-Exo, the utilization of MSC-Exo may be promising therapeutic for pathological scars. However, different immune cells function differently during wound repair and scar formation. The immunoregulatory mechanism of MSC-Exo would differ among different immune cells and molecules. Herein, this review gave a comprehensive summary of MSC-Exo immunomodulating different immune cells in wound healing and scar formation to provide basic theoretical references and therapeutic exploration of inflammatory wound healing and pathological scars.

Exosomal MiR-381 from M2-polarized macrophages attenuates urethral fibroblasts activation through YAP/GLS1-regulated glutaminolysis

OBJECTIVE AND DESIGN

Post-traumatic urethral stricture is a clinical challenge for both patients and clinicians. Targeting glutamine metabolism to suppress excessive activation of urethral fibroblasts (UFBs) is assumed to be a potent and attractive strategy for preventing urethral scarring and stricture.

MATERIAL OR SUBJECTS

In cellular experiments, we explored whether glutaminolysis meets the bioenergetic and biosynthetic demands of quiescent UFBs converted into myofibroblasts. At the same time, we examined the specific effects of M2-polarized macrophages on glutaminolysis and activation of UFBs, as well as the mechanism of intercellular signaling. In addition, findings were further verified in vivo in New Zealand rabbits.

RESULTS

It revealed that glutamine deprivation or knockdown of glutaminase 1 (GLS1) significantly inhibited UFB activation, proliferation, biosynthesis, and energy metabolism; however, these effects were rescued by cell-permeable dimethyl α-ketoglutarate. Moreover, we found that exosomal miR-381 derived from M2-polarized macrophages could be ingested by UFBs and inhibited GLS1-dependent glutaminolysis, thereby preventing excessive activation of UFBs. Mechanistically, miR-381 directly targets the 3'UTR of Yes-associated protein (YAP) mRNA to reduce its stability at the transcriptional level, ultimately downregulating expression of YAP, and GLS1. In vivo experiments revealed that treatment with either verteporfin or exosomes derived from M2-polarized macrophages significantly reduced urethral stricture in New Zealand rabbits after urethral trauma.

CONCLUSION

Collectively, this study demonstrates that exosomal miR-381 from M2-polarized macrophages reduces myofibroblast formation of UFBs and urethral scarring and stricture by inhibiting YAP/GLS1-dependent glutaminolysis.

Recent developments in adipose tissue-secreted factors and their target organs

The white adipose tissue's primary roles are to store and mobilise energy, which is very different from the brown adipose tissue's function of using fuel to generate heat and maintain the body temperature. The adipose tissues (ATs), co-ordinately with the other organs, sense energetic demands and inform of their reserves before embarking on energetically demanding physiological functions. It is not surprising that ATs exhibit highly integrated regulatory mechanisms mediated by a diversified secretome, including adipokines, lipokines, metabolites and a repertoire of extracellular miRNAs that contribute to integrating the function of the AT niche and connect the AT through paracrine and endocrine effects with the whole organism. Characterising the adipose secretome, its changes in health and disease, regulation by ageing and gender and their contribution to energy homoeostasis is necessary to optimise its use for personalised strategies to prevent or reverse metabolic diseases.

Advancements in adipose-derived stem cell therapy for skin fibrosis

Pathological scarring and scleroderma, which are the most common conditions of skin fibrosis, pathologically manifest as fibroblast proliferation and extracellular matrix (ECM) hyperplasia. Fibroblast proliferation and ECM hyperplasia lead to fibrotic tissue remodeling, causing an exaggerated and prolonged wound-healing response. The pathogenesis of these diseases has not been fully clarified and is unfortunately accompanied by exceptionally high medical needs and poor treatment effects. Currently, a promising and relatively low-cost treatment has emerged-adipose-derived stem cell (ASC) therapy as a branch of stem cell therapy, including ASCs and their derivatives-purified ASC, stromal vascular fraction, ASC-conditioned medium, ASC exosomes, etc., which are rich in sources and easy to obtain. ASCs have been widely used in therapeutic settings for patients, primarily for the defection of soft tissues, such as breast enhancement and facial contouring. In the field of skin regeneration, ASC therapy has become a hot research topic because it is beneficial for reversing skin fibrosis. The ability of ASCs to control profibrotic factors as well as anti-inflammatory and immunomodulatory actions will be discussed in this review, as well as their new applications in the treatment of skin fibrosis. Although the long-term effect of ASC therapy is still unclear, ASCs have emerged as one of the most promising systemic antifibrotic therapies under development.

TNF-α/IL-1β-licensed hADSCs alleviate cholestatic liver injury and fibrosis in mice via COX-2/PGE2 pathway

BACKGROUND

Adipose tissue-derived stem cell (ADSC) transplantation has been shown to be effective for the management of severe liver disorders. Preactivation of ADSCs enhanced their therapeutic efficacy. However, these effects have not yet been examined in relation to cholestatic liver injury.

METHODS

In the present study, a cholestatic liver injury model was established by bile duct ligation (BDL) in male C57BL/6 mice. Human ADSCs (hADSCs) with or without tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) pretreatment were administrated into the mice via tail vein injections. The efficacy of hADSCs on BDL-induced liver injury was assessed by histological staining, real-time quantitative PCR (RT-qPCR), Western blot, and enzyme-linked immune sorbent assay (ELISA). In vitro, the effects of hADSC conditioned medium on the activation of hepatic stellate cells (HSCs) were investigated. Small interfering RNA (siRNA) was used to knock down cyclooxygenase-2 (COX-2) in hADSCs.

RESULTS

TNF-α/IL-1β preconditioning could downregulate immunogenic gene expression and enhance the engraftment efficiency of hADSCs. Compared to control hADSCs (C-hADSCs), TNF-α/IL-1β-pretreated hADSCs (P-hADSCs) significantly alleviated BDL-induced liver injury, as demonstrated by reduced hepatic cell death, attenuated infiltration of Ly6G + neutrophils, and decreased expression of pro-inflammatory cytokines TNF-α, IL-1β, C-X-C motif chemokine ligand 1 (CXCL1), and C-X-C motif chemokine ligand 2 (CXCL2). Moreover, P-hADSCs significantly delayed the development of BDL-induced liver fibrosis. In vitro, conditioned medium from P-hADSCs significantly inhibited HSC activation compared to that from C-hADSCs. Mechanistically, TNF-α/IL-1β upregulated COX-2 expression and increased prostaglandin E2 (PGE2) secretion. The blockage of COX-2 by siRNA transfection reversed the benefits of P-hADSCs for PGE2 production, HSC activation, and liver fibrosis progression.

CONCLUSION

In conclusion, our results suggest that TNF-α/IL-1β pretreatment enhances the efficacy of hADSCs in mice with cholestatic liver injury, partially through the COX-2/PGE2 pathway.

Challenges and Opportunities for Extracellular Vesicles in Clinical Oncology Therapy

Extracellular vesicles (EVs) are membrane-bound vesicles that can be released by all cell types. They may have different biogenesis, physical features, and cargo. EVs are important biomarkers for the diagnosis and prediction of many diseases due to their essential role in intercellular communication, their highly variable cargoes, and their accumulation in various body fluids. These natural particles have been investigated as potential therapeutic materials for many diseases. In our previous studies, the clinical usage of tumor-cell-derived microparticles (T-MPs) as a novel medication delivery system was examined. This review summarizes the clinical translation of EVs and related clinical trials, aiming to provide suggestions for safer and more effective oncology therapeutic systems, particularly in biotherapeutic and immunotherapeutic systems.

Exosomes Derived from Adipose Stem Cells Enhance Bone Fracture Healing via the Activation of the Wnt3a/β-Catenin Signaling Pathway in Rats with Type 2 Diabetes Mellitus

Nonunion and delayed union are common complications of diabetes mellitus that pose a serious health threat to people. There are many approaches that have been used to improve bone fracture healing. Recently, exosomes have been regarded as promising medical biomaterials for improving fracture healing. However, whether exosomes derived from adipose stem cells can promote bone fracture healing in diabetes mellitus remains unclear. In this study, adipose stem cells (ASCs) and exosomes derived from adipose stem cells (ASCs-exos) are isolated and identified. Additionally, we evaluate the in vitro and in vivo effects of ASCs-exos on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and bone repair and the regeneration in a rat model of nonunion via Western blotting, immunofluorescence assay, ALP staining, alizarin red staining, radiographic examination and histological analysis. Compared with controls, ASCs-exos promoted BMSC osteogenic differentiation. Additionally, the results of Western blotting, radiographic examination and histological analysis show that ASCs-exos improve the ability for fracture repair in the rat model of nonunion bone fracture healing. Moreover, our results further proved that ASCs-exos play a role in activating the Wnt3a/β-catenin signaling pathway, which facilitates the osteogenic differentiation of BMSCs. All these results show that ASCs-exos enhance the osteogenic potential of BMSCs by activating the Wnt/β-catenin signaling pathway, and also facilitate the ability for bone repair and regeneration in vivo, which provides a novel direction for fracture nonunion in diabetes mellitus treatment.

An Overview of Inter-Tissue and Inter-Kingdom Communication Mediated by Extracellular Vesicles in the Regulation of Mammalian Metabolism

Obesity and type 2 diabetes are associated with defects of insulin action in different tissues or alterations in β-cell secretory capacity that may be triggered by environmental challenges, inadequate lifestyle choices, or an underlying genetic predisposition. In addition, recent data shows that obesity may also be caused by perturbations of the gut microbiota, which then affect metabolic function and energy homeostasis in the host. Maintenance of metabolic homeostasis in complex organisms such as mammals requires organismal-level communication, including between the different organs and the gut microbiota. Extracellular vesicles (EVs) have been identified in all domains of life and have emerged as crucial players in inter-organ and inter-kingdom crosstalk. Interestingly, EVs found in edible vegetables or in milk have been shown to influence gut microbiota or tissue function in mammals. Moreover, there is a multidirectional crosstalk mediated by EVs derived from gut microbiota and body organs that has implications for host health. Untangling this complex signaling network may help implement novel therapies for the treatment of metabolic disease.

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

Liver fibrosis is a global health problem caused by chronic liver injury resulting from various factors. Hepatic stellate cells (HSCs) have been found to play a major role in liver fibrosis, and pathological stimuli lead to their transdifferentiation into myofibroblasts. Complex multidirectional interactions between HSCs, immune cells, and cytokines are also critical for the progression of liver fibrosis. Despite the advances in treatments for liver fibrosis, they do not meet the current medical needs. Exosomes are extracellular vesicles of 30-150 nm in diameter and are capable of intercellular transport of molecules such as lipids, proteins and nucleic acids. As an essential mediator of intercellular communication, exosomes are involved in the physiological and pathological processes of many diseases. In liver fibrosis, exosomes are involved in the pathogenesis mainly by regulating the activation of HSCs and the interaction between HSCs and immune cells. Serum-derived exosomes are promising biomarkers of liver fibrosis. Exosomes also have promising therapeutic potential in liver fibrosis. Exosomes derived from mesenchymal stem cells and other cells exhibit anti-liver fibrosis effects. Moreover, exosomes may serve as potential therapeutic targets for liver fibrosis and hold promise in becoming drug carriers for liver fibrosis treatment.