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How gut bacteria affect health, using mice


Gut microbiome

Two US studies have used mice to shed light on the remarkable effects of gut bacteria, both on improving cancer treatment and in the production of hormones that can affect the brain.


Research led by Harvard Medical School, in Massachusetts, using mice and lab studies, identified two types of human gut bacteria that can modify steroids – hormones derived from cholesterol that act as chemical messengers.


The team found that these bacteria first altered steroids found in bile, which are involved in the immune function and metabolism, and then converted the same steroids into sex hormones, which influence both pregnancy and menstruation, and the brain.


One of these sex hormones – allopregnanolone – is produced during pregnancy, and researchers found that the hormone, plus genetic traces of the gut bacteria, were present, in the faecal samples of pregnant women, at higher levels than for women who are not pregnant. This suggests that these bacteria contribute to making allopregnanolone during pregnancy.


Low levels of allopregnanolone have previously been linked to postpartum depression, which raises the possibility that these bacteria could either protect against or drive this condition – and providing further evidence that the gut microbiome can influence our mental health.


Meanwhile, a study at Washington University School of Medicine (WUSM), Missouri, found that a different type of gut bacteria boosted the effectiveness of an immunotherapy used to treat cancer.

Commonly, cohabiting mice share bacteria with each other, and the researchers saw that when two types of mice with cancer were housed together, despite one having a protein that makes immunotherapy less effective and one without, both types of mice responded well to immunotherapy.


There was also more of this gut bacteria in mice that were successfully treated with immunotherapy, suggesting the bacteria is important for enhancing its effects against cancer.


Marco Colonna, at WUSM, said: “Identifying such microbial partners is an important step in developing probiotics to help improve the effectiveness of immunotherapy drugs and benefit more cancer patients.”


2 Comments


su xeko
su xeko
Jun 14

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Cato Athena
Cato Athena
Jun 12

This disease is quite dangerous, you should pay more attention to your health moto x3m

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