Hongmei Shao; Junjie Chen
Abstract
Background: Psoriasis is a chronic inflammatory skin disorder characterized by elevated levels of proinflammatory cytokines. Mesenchymal stem cells (MSCs) have demonstrated therapeutic potential, yet the specific mechanisms involved are not fully understood. In this study, we investigated the effectiveness ...
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Background: Psoriasis is a chronic inflammatory skin disorder characterized by elevated levels of proinflammatory cytokines. Mesenchymal stem cells (MSCs) have demonstrated therapeutic potential, yet the specific mechanisms involved are not fully understood. In this study, we investigated the effectiveness of extracellular vesicles (EVs) derived from MSCs that were genetically modified to overexpress miR-146a, in a mouse model of psoriasis.Methods: To enhance miR-146a expression, MSCs were transfected, and their EVs were subsequently purified. Thirty mice were randomly assigned to three groups and induced with imiquimod cream to develop psoriasis-like skin lesions. The treatment groups included: (1) a control group administered PBS, (2) a group treated with EVs containing a control miRNA (miR-control EVs), and (3) a group receiving EVs enriched with miR-146a (miR-146a-EVs). EVs were administered intravenously and lesions were evaluated. Following intravenous administration of EVs, the severity of skin lesions was assessed. Concentrations of key cytokines, including IFN-γ, IL-17, TNF-α, IL-23, IL-6, IL-1β, TGF-β, IL-10, and IL-4, were quantified in both spleen and skin tissue lysates using ELISA and qRT-PCR techniques.Results: The experimental findings demonstrated that the administration of miR-146a-enriched EVs led to a significant improvement in clinical symptoms. There were substantial reductions observed in combined erythema, scaling, and skin thickness measurements compared to untreated controls. Additionally, levels of proinflammatory cytokines IFN-γ, IL-17, TNF-α, IL-23, IL-6, and IL-1β were significantly downregulated in the miR-146a-EV group, while anti-inflammatory TGF-β, IL-10 and IL-4 were upregulated. The same results were obtained in the spleens of mice.Conclusion: EVs derived from miR-146a-modified MSCs effectively reduced psoriasis-like inflammation by modulating cytokine expression. This novel cell-free therapy holds promise for the treatment of psoriasis.
Ali Fotouhi; Maryam Hosseini; Ali Aghebati-Maleki; Mohammad Sadegh Soltani-Zangbar; Sara Parsania; Amirhossein Mardi; Leili Aghebati-Maleki
Abstract
Background: Osteoarthritis (OA) is the most common joint disease worldwide. Routine treatment options are limited, and total knee replacement surgeries often come with complications. In recent years, the use of biologics, such as Wharton’s jelly (Wj) derived from the umbilical cord (UC), has gained ...
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Background: Osteoarthritis (OA) is the most common joint disease worldwide. Routine treatment options are limited, and total knee replacement surgeries often come with complications. In recent years, the use of biologics, such as Wharton’s jelly (Wj) derived from the umbilical cord (UC), has gained popularity. While mesenchymal stem cells (MSCs) derived from Wj show promise in restoring articular cartilage, they also have some limitations. Recent studies have indicated that exosomes isolated from acellular Wj may offer advantages under certain conditions.Objective: To investigate the anti-inflammatory properties of exosomes isolated from Wj in synoviocytes.Methods: Decellularization of Wj was performed using sterile umbilical cords obtained from patients. Next, the exosomes were isolated from Wj using ultracentrifugation. After characterizing the exosomes, they were co-cultured with inflammatory synovial fibroblast cells (HIG-82) for 24 hours. Then, the gene expression levels and protein contents of some important inflammatory mediators including metalloproteinase-13 (MMP-13), cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (iNOS) were measured in the cells using real-time PCR and ELISA tests, respectively.Results: The expression levels of MMP-13, COX-2, and iNOS genes were significantly reduced in the cultured cells treated with exosomes compared to untreated cells. Moreover, the content of MMP-13, COX-2, and iNOS proteins were significantly lower in the supernatant of the cultured cells compared to the control.Conclusion: Wj-derived exosomes exhibit notable anti-inflammatory properties, which can help mitigate inflammation in the synovial environment of joints. However, further research is required to fully understand their benefits and potential applications in treating osteoarthritis.
