Abstract
Testosterone deficiency can cause abnormal lipid metabolism in men, leading to hyperlipidemia. We identified the testosterone-degrading bacterium Pseudomonas nitroreducens in the fecal samples of male patients with hyperlipidemia. Gastric administration of P. nitroreducens in mice led to testosterone deficiency and elevated blood lipid levels. Whole-genome sequencing of P. nitroreducens revealed the presence of 3/17β-hydroxysteroid dehydrogenase (3/17β-HSD), a gene responsible for testosterone degradation, which is also associated with hyperlipidemia. Microbiota analysis of fecal samples collected from 158 patients with hyperlipidemia and 151 controls revealed that the relative abundance of P. nitroreducens and 3/17β-HSD in the fecal samples of patients with hyperlipidemia was significantly higher than that in controls. These results suggest that P. nitroreducens and 3/17β-HSD may be related to the onset of testosterone deficiency-induced hyperlipidemia. Therefore, treatments targeted at eradicating testosterone-degrading bacteria are a potential future option for patients with testosterone-induced hyperlipidemia and should thus be studied further.