Bacteria behind depression identified, feeds on oestrogen steroid hormone in women: study

A single enzyme has been identified as the major cause of depression, one of the major mental health concerns across the world. A new study at Wuhan University has spotted it in women in their reproductive years.

According to researcher Di Li and colleagues, estradiol is a crucial compound in supporting a healthy mood. The decline of this estrogen steroid hormone can lead to depressive symptoms in women.

Scientists isolated estradiol-degrading microbes from the feces of premenopausal females with depression. When this was given to mice, it led to a decline in estradiol and symptoms of depression. Upon further research, the team labeled the strain of bacteria Klebsiella aerogenes TS2020, said the paper published in Science Alert.

The team took a sample of the microbiome from women with depression and place it on an agar plate. They were only given estradiol. In two hours, over 60% of estradiol degraded into estrone and the microbiome thrived as white blobs with smooth and hazy edges. "These results show that K. aerogenes TS2020 can reduce the serum estradiol level in mice and induce depressive-like behaviors. Additionally, cefotaxime administration can alleviate such depressive-like behaviors in mice."

These findings may lead to better interventions and treatments for depression in premenopausal women.