An enzyme has been found in the brain of men which is responsible for sex drive.
A study from Northwestern University investigated the role of aromatase in the organ and found the enzyme converts testosterone into oestrogen.
These hormones are known as the male and female sex hormones, respectively, but creating oestrogen is crucial for male sexual function.
It is needed in high levels to drive libido and is essential for erectile function. Without oestrogen being made from testosterone, a man’s sex drive plummets.
Researchers also found aromatase is produced by a single gene, called Cyp19a1, opening up potential routes to target the enzyme.
By successfully isolating the gene responsible for creating the enzyme, researchers hope to develop drugs to treat male sex addiction and low libido.
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A study from Northwestern University investigated the role of aromatase in the brain and found the enzyme converts testosterone into oestrogen. This process is key to mal esex drive (stock)
The role of aromatase in the brain has been the topic of lots of research, with scientists struggling to understand its purpose.
Discovering it converts testosterone into oestrogen, and the gene responsible for producing the enzyme, is a major breakthrough.
‘This is the first key finding to explain how testosterone stimulates sexual desire,’ said senior author Dr Serdar Bulun at Northwestern University.
‘For the first time, we demonstrated conclusively that the conversion of testosterone to estrogen in the brain is critical to maintain full sexual activity or desire in males. Aromatase drives that.’
Researchers removed the aromatase gene from the brain of male lab mice and put them in cages with a female mouse.
Subsequent sexual activity was slashed in half despite the rodents having higher than normal levels of testosterone.
The inability to convert the hormone from testosterone to oestrogen had a clear impact on sexual desire.
Converting testosterone into oestrogen is needed in high levels to drive libido and is essential for erectile function. Without it, the sex drive of a man plummets. Researchers also found aromatase is produced by a single gene, called Cyp19a1 (stock)
When flirting, women look for seriousness and maturity, but men want beauty
The secret to successful flirting still lies in appearance rather than corny chat up lines — but women also like intelligence and tenderness in a man, a study found.
Experts from Cyprus surveyed more than 800 volunteers — finding that men and woman both fall for people who are good looking, well dressed and charming.
Men are reportedly seen as particularly good catches if their appearance and what they said suggested that they were possessed of intelligence and wealth.
The researchers also found that the gentle approach worked best — with a suitor who was polite, respectful and did not ‘move too fast’ likely to be more successful.
The findings could help counsellors and psychologists deal with clients who have confidence issues, or problems with social interaction.
‘Male mice partially lost interest in sex,’ said co-author Dr. Hong Zhao.
‘Aromatase is the key enzyme for estrogen production. Estrogen has functions in males and females.
‘Testosterone has to be converted to estrogen to drive sexual desire in males.’
Aromatase deficiency is very rare in humans, but there have been documented cases. These men suffer from chronically elevated testosterone levels.
When undergoing with oestrogen therapy, the aromatase-deficient men reported significant improvements in the frequency of sexual activity.
However, the knoc-on implications of this latest study reach far beyond aromatase-deficient men and could help modulate sexual desire in large groups of men.
For example, many men suffer from low sexual desire, clinically known as hypoactive sexual desire disorder.
It can be brought on by some medications, including a group of antidepressants known as SSRIs.
If drugs can be created which target the aromatase enzyme in the brain then it could lead to heightened sexual desire, the researchers say.
At the other end of the scale, it could also be used to tackle compulsive sexual desire.
Existing treatments have serious side-effects but new selective drugs could avoid this.
The full findings are published in the journal Endocrinology.