Human Umbilical Cord MSC-Derived Exosomes Treatment Reduces Liver Inflammation and Improves Liver Function in an Experimental Model of Liver Fibrosis
Human Umbilical Cord MSC-Derived Exosomes Treatment Reduces Liver Inflammation and Improves Liver Function in an Experimental Model of Liver Fibrosis
Bahare Niknam,1Kaveh Baghaei,2Davar Amani,3,*
1. Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2. Gastroenterology and Liver Diseases Research center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran 3. Department of Immunology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Introduction: Cirrhosis is one of the causes of increased mortality in developing countries. Determining the prevalence of cirrhosis is difficult and may be much more than what is reported because the previous stages underlying it, including liver fibrosis, are asymptomatic and the disease is not diagnosed during that period. Liver fibrosis is a wound-healing response characterized by the accumulation of extracellular matrix (ECM) following liver injury, leading to organ failure through inflammation and the release of fibrotic biomarkers. Therefore, the development of anti-inflammatory and antifibrotic therapies is desired. Mesenchymal stem cells (MSCs) with their anti-inflammatory and immunomodulatory properties are increasingly being used as a treatment for liver fibrosis. Studies show that the therapeutic effects caused by MSC are mostly paracrine and through extracellular vesicles, including exosomes. In addition to having the same function as their parent cells, exosomes also have advantages such as smaller size and less complexity, thus being easier to produce and store, low toxicity, and low immunogenicity.
This study aims to investigate the effect of Umbilical Cord mesenchymal stem cells derived exosomes (UCMSC-EX) in an established carbon tetrachloride (CCl4)-induced liver fibrosis mouse model
Methods: The UC-MSCS were isolated by the explant method, in such a way that after removing the blood vessels, small pieces of the human umbilical cord were cultured in a flask. After evaluating the morphology of the MSCs, the multipotency of the isolated cells was checked with their ability to differentiate into osteocytes and adipocytes. In addition, the immunophenotype of UCMSC in terms of the expression of CD73, CD90, CD105, CD34, and CD45 was studied by flow cytometry. The exosome was isolated from the supernatant from culture of the human umbilical cord-derived mesenchymal stem cell. Exosomes are purified by commercial kit and characterized by transmission and scanning electron microscopy, dynamic light scattering, and bicinchoninic acid assay. We established a 6-week carbon tetrachloride (CCl4)-induced mouse model of liver fibrosis, then we administered UCMSC-EX for three weeks. The liver function and inflammation were assessed by biochemistry and Real-time PCR.
Results: Biochemical analyses were performed to evaluate liver function recovery after UCMSC-EX treatment. Serum levels of ALT, AST, TBIL, and ALP were significantly suppressed in groups treated with UCMSC-EX compared to the untreated liver fibrosis group. In addition, the serum level of Alb in the UCMSC-EX treated group was higher than that of the untreated liver fibrosis group. These results indicate the improvement of liver function in the UCMSC-Exosomes treated group. Next, we detected the expression of inflammatory factors in liver tissue by qRT-PCR. Compared with the untreated liver fibrosis group, the expression of inflammatory factors including IL-6, IL-17, and STAT3 was significantly decreased in the UCMSC-EX treatment group in comparison to liver fibrosis group. Therefore, treatment with UCMSC-EX had anti-inflammatory effects, as evidenced by improved liver function and reduced inflammation.
Conclusion: Taken together, our results clearly show that UCMSC-EX treatment reduces liver fibrosis in vivo. In addition, the administration of UCMSC-EX reduces liver fibrosis by restoring liver function and inhibiting the expression of pro-inflammatory genes. Therefore, the use of UCMSC-EX provides a new and promising therapeutic strategy for liver fibrosis in the clinical setting.