The gut commensal fungus, Candida parapsilosis, promotes high fat-diet induced obesity in mice.

Gut fungi is known to play many important roles in human health regulations. Herein, we investigate the anti-obesity efficacy of the antifungal antibiotics (amphotericin B, fluconazole and 5-fluorocytosine) in the high fat diet-fed (HFD) mice. Supplementation of amphotericin B or fluconazole in water can effectively inhibit obesity and its related disorders, whereas 5-fluorocytosine exhibit little effects. The gut fungus Candida parapsilosis is identified as a key commensal fungus related to the diet-induced obesity by the culture-dependent method and the inoculation assay with C. parapsilosis in the fungi-free mice. In addition, the increase of free fatty acids in the gut due to the production of fungal lipases from C. parapsilosis is confirmed as one mechanism by which C. parapsilosis promotes obesity. The current study demonstrates the gut C. parapsilosis as a causal fungus for the development of diet-induced obesity in mice and highlights the therapeutic strategy targeting the gut fungi.