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bioRxiv · 10.1101/2025.04.01.646656

In vivo efficacy of L-ascorbic acid in restricting cholera pathogenesis

Abstract

In the last three centuries, our world has experienced seven cholera pandemics. Cholera is a deadly diarrheal disease caused by Vibrio cholerae, an important member of the gamma-proteobacteria. Despite conventional treatments like antibiotics, vaccines, and ORS, the 7th cholera pandemic is still a major threat to developing nations. L-ascorbic acid was recently shown to effectively kill the Vibrio cholerae cells in vitro under various growth conditions mimicking the in vivo host conditions, including growth in the presence of bile salts, growth of acid-adapted V. cholerae, and growth in the presence of various ORS components. In the current study, we extend this work and test the efficacy of L-ascorbic acid in animal models (rabbit ileal loop and the removable intestinal tie adult rabbit diarrhea). We show that L-ascorbic acid can effectively reduce the bacterial load in both the rabbit models as well as fast-track the recovery from the diarrheal symptoms. ImportanceCholera is a severe human diarrheal disease that affects millions each year. Cholera treatment is primarily oral rehydration to balance the voluminous fluid loss. Previous studies have found that L-ascorbic acid (L-AA) is effective at inhibiting growth of Vibrio cholerae, the causative agent of cholera. Thus L-AA has potential as am inexpensive cholera therapeutic. Here, L-AA is tested in rabbit models to determine whether it can inhibit the effects of V. cholerae infection. Results suggest that L-AA treatment inhibits bacterial proliferation and leads to shortened recovery from disease.

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Halder, P., Sen, H., Das, S., Nandy, P., Mukhopadhyay, A. K., Withey, J. H., Raychaudhuri, S., Koley, H.. 2025-04-02. In vivo efficacy of L-ascorbic acid in restricting cholera pathogenesis. https://doi.org/10.1101/2025.04.01.646656

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