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Ulcerative colitis (UC) is a long-term, recurrent inflammatory bowel disease for which no effective cure is yet available in the clinical setting. Repairing the barrier dysfunction of the colon and reducing intestinal inflammation are considered key objectives to cure UC. Here we demonstrate a novel therapeutic strategy based on a C60 fullerene suspension (C60FS) to treat dinitrobenzene sulfonic acid-induced UC in an animal model. C60FS can repair the barrier dysfunction of UC and effectively promote the healing of ulcers; it also manifests better treatment effects compared with mesalazine enema. C60FS can reduce the numbers of basophils in the blood of UC rats and mast cells in the colorectal tissue, thereby effectively alleviating inflammation. The expression of H1R, H4R, and VEGFR2 receptors in colorectal tissues is inhibited by C60FS, and the levels of histamine and prostaglandin in the rat blood are reduced. This work presents a reliable strategy based on fullerene to cure UC and provides a novel guide for UC treatment.
相似文献Bacterial infections caused by Gram-negative pathogens represent a growing burden for public health worldwide. Despite the urgent need for new antibiotics that effectively fight against pathogenic bacteria, very few compounds are currently under development or approved in the clinical setting. Repurposing compounds for other uses offers a productive strategy for the development of new antibiotics. Here we report that the multifaceted melatonin effectively improves survival rates of mice and decreases bacterial loads in the lung during infection. Mechanistically, melatonin specifically inhibits the activity of citrate synthase of Gram-negative pathogens through directly binding to the R300, D363, and H265 sites, particularly for the notorious Pasteurella multocida. These findings highlight that usage of melatonin is a feasible and alternative therapy to tackle the increasing threat of Gram-negative pathogen infections via disrupting metabolic flux of bacteria.
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