Dear Evolution, thank you for oestrogen

Women, thank your lucky stars for oestrogen. There has historically been a perception that women handle stress and general panic better than men, but new research from the University of Buffalo now proves it and points to a reason.

According to the animal study published in Molecular Psychiatry on July 9, it’s all thanks to oestrogen. “Previously studies have found that females are more resilient to chronic stress and now our research has found the reason why,” says senior author Prof Zhen Yan, from the university’s department of physiology and biophysics. “We have examined the molecular mechanism underlying gender specific stress.”

And it all comes down to oestrogen, which appears to have a protective effect. In the study, rats were exposed to a week of physical restraints, and I think we can all agree that a week of being tied down would be rather stressful.

After the week, the female rats were still able to remember and recognise objects they have been exposed to previously. Males were less sprightly and aware after the week, and the same stress appeared to impair their short-term memory.

By manipulating the amount of oestrogen produced in the brain, the researchers were able to gauge the effects of oestrogen on the different sexes. “When oestrogen signalling in the brains of females was blocked, stress exhibited detrimental effects on them,” Yan says. “When oestrogen signalling was activated in males, the detrimental effects of stress were blocked.”

However, it would appear that this stress-protection oestrogen is made in the brain, because female rats that had had their ovaries removed still enjoyed the protective effects of oestrogen.

More than anything, this research made me feel sorry for the rats, but also super thankful for oestrogen. So women, if you’re feeling stressed today, realise it could be a worse – you could be a man. (As for the chaps … sorry about that – blame evolution.)

Science snippet for the week

Now that is something that you literally don’t see everyday. In fact, we haven’t seen it before – scientists from the Atacama Large Millimetre/submillimetre Array (Alma, for short) in Chile have witnessed, in unprecedented details, the birth of a massive star – more than 500 times the mass of the Sun and many times brighter – in a stellar womb (which is a romantic way of saying a bloody gigantic dust cloud about 10 000 light years away. There are a number of theories about how massive stars are formed, and they’ve remained theories because the formation take a long, long time and we haven’t witnessed an entire star formation before. The team’s observations led them to believe that dust clouds “collapse” in on themselves, coalescing into a star.

“The remarkable observations from Alma allowed us to get the first really in-depth look at what was going on within this cloud,” said lead author Dr Nicolas Peretto, from Cardiff University. “We wanted to see how monster stars form and grow, and we certainly achieved our aim. One of the sources we have found is an absolute giant — the largest protostellar core ever spotted in the Milky Way!

“Even though we already believed that the region was a good candidate for being a massive star-forming cloud, we were not expecting to find such a massive embryonic star at its centre. This cloud is expected to form at least one star 100 times more massive than the Sun and up to a million times brighter. Only about one in 10 000 of all the stars in the Milky Way reach that kind of mass.”