Caffeine and naloxone treated mesenchymal stem cells improve symptoms and reduce inflammation in a mouse model of ulcerative colitis

Ulcerative colitis (UC) causes ulcers in the colon and rectum, leading to abdominal pain, diarrhea, and rectal bleeding, and if left untreated, can lead to serious complications. The therapeutic effects of mesenchymal stem cells (MSCs) on experimental models of UC have been proven. Since the microenvironment around these cells is crucial in maintaining cell proliferation, differentiation, metabolism, and overall function, this study aims to evaluation the role of caffeine and naloxone as a new microenvironment for MSCs in reducing inflammation and improving symptoms in an experimental model of UC. A group of 40 outbred NMRI mice were studied and divided randomly into four equal groups (N = 10 each group). UC was induced in all groups using acetic acid. The first group (control) was treated with phosphate buffer saline (PBS), the second group with MSCs-Caffeine, the third with MSCs-Naloxone, and the fourth with Mesalazine. The disease activity index (DAI), tissue damage, myeloperoxidase (MPO) activity, nitric oxide (NO) levels, and the production of IL-1, IL-6, and TNF-α cytokines were evaluated. Our research demonstrated that all treatments were effective in improving the symptoms and reducing inflammatory markers in mice with colitis. Among the two MSCs treatments, the MSCs-Caffeine was found to be the most potent in reducing the levels of NO, IL-1, IL-6, tissue damage (P