How microorganisms control sex hormones

The microbiome, the complex community of trillions of bacteria and viruses, plays a crucial role in many aspects of our health – from digestion to the immune system and brain function.

The microbiome is also closely linked to sex hormones and may thus play a crucial role in the development of diseases such as ovarian cancer, osteoporosis or polycystic ovary syndrome.

The fascinating connection between microbiome and hormones

Research shows that there is a bidirectional relationship between the gut microbiome and our sex hormones. This means that not only do hormones influence the composition of the microbiome, but the microbiome itself actively regulates the level of hormones in the body. This interaction is a remarkable example of how profound the connection between microorganisms and humans is.

For example, it has been observed that the microbiome is composed differently in men and women. Studies in mice and humans have shown that testosterone, estrogen and progesterone – the main sex hormones – can influence the diversity and composition of gut bacteria. In men, higher amounts of certain bacterial families such as Bacteroidaceae were found, while other bacterial groups dominate in women. This gender-specific composition is of enormous importance as it could explain why certain diseases occur with different frequencies in men and women.

The female microbiome

In the following, the focus will be on the female microbiome and its correlation to hormone-related diseases in women, and how health can be taken into one’s own hands.

Women and osteoporosis

One example of a hormone-related disease is postmenopausal osteoporosis. This form of bone loss, which occurs in women after menopause, is triggered by the drop in estrogen levels.

Estrogen plays an important role in bone metabolism by inhibiting bone breakdown and promoting bone formation. With the decline of estrogen, the activity of osteoclasts, which break down bone, increases while the activity of osteoblasts, which form bone, decreases. This leads to an imbalance in which more bone is broken down than newly formed, reducing bone density and increasing the risk of fractures.

Interestingly, the gut microbiome appears to play a central role in this process. Experiments on mice have shown that a disturbed microbiota intensifies bone loss.

Certain bacteria in the gut can modify inactive estrogen via special enzymes (beta-glucuronidase) so that it can be reactivated and reabsorbed into the bloodstream.

Overall, the diversity and balance of the microbiome is important for optimal hormone regulation. In addition, a severely altered microbiome (dysbiosis) can disrupt the intestinal barrier and cause substances that trigger inflammation to enter the bloodstream. These inflammatory processes ultimately lead to an increase in osteoclast activity and thus to increased bone resorption.

A healthy and diverse microbiome can therefore stop or at least slow down bone loss. The intake of specific probiotics could also open up completely new perspectives for the prevention and treatment of osteoporosis.

Women and polycystic ovary syndrome

Another exciting area is polycystic ovary syndrome (PCOS), a common hormonal disorder in women of childbearing age. Women with PCOS often suffer from menstrual irregularities, obesity, and increased production of androgens, the male sex hormones. Recent research suggests that women with PCOS have a significantly lower diversity of the gut microbiome than healthy women. Impaired gut flora could therefore contribute to insulin resistance and increased androgen levels, which are characteristic of PCOS.

A healthy microbiome can also help here and alleviate the symptoms of PCOS.

Women and ovarian cancer

One of the most surprising findings is the possible link between the gut microbiome and ovarian cancer. Ovarian cancer is one of the deadliest gynecological cancers, and the exact causes are still not fully understood. However, there is evidence that the microbiome may play a role in the development and progression of this disease. Bacteria can lead to an excessive increase in estrogens and thus promote the growth of ovarian tumors. As described above, this happens when inactive estrogen is reactivated.

This clearly shows that only a balanced level of estrogen is healthy for the body. While too much estrogen can promote ovarian tumors, too little estrogen can cause osteoporosis. This in turn requires a balanced equilibrium in the microbiome.

Moreover, there is evidence that the gut microbiome could influence the effectiveness of chemotherapy drugs such as cyclophosphamide. In mice, a disrupted gut flora led to the treatment being less effective. This suggests that a healthy gut flora could not only help to prevent cancer but also to improve cancer treatment.

We are in charge of our own destiny.

Even if the focus here was on the female microbiome, the same applies to men. The findings on the connection between the gut microbiome and sex hormones open up exciting new possibilities in medicine, but also in self-responsible prevention. Understanding these complex interactions could, in principle, lead to future therapies that aim to modulate the microbiome to correct hormonal imbalances and treat sex hormone-dependent diseases.

But what is also becoming particularly clear – and this is the really good news – is that investing in your own microbiome, in the form of sufficient exercise, a healthy diet and stress-relieving activities, definitely pays off. It can help to fight or even prevent diseases.

With it, anyone can break out of the passive role and instead actively and successfully. (JS)

_________________________________________________

Further reading/sources:

He S, Li H, Yu Z, Zhang F, Liang S, Liu H, Chen H and Lü M (2021) The Gut Microbiome and Sex Hormone-
Related Diseases. Front. Microbiol. 12:711137.
https://doi.org/10.3389/fmicb.2021.711137

Image material:

Header: © markin; www.depositphotos.com; Text: © katerynakon – www.depositphotos.com