Does estrogen help women respond better to stress?

The ability to tackle with stress may be attributed, at least in part, to gender differences, suggests an intriguing new study. According to researchers, women seem to have the edge in dealing with difficult conditions compared to son men.

Experts theorize that it might have been due to the fact that women have the protective effect of estrogen.

Senior author Zhen Yan, PhD, a professor in the Department of Physiology and Biophysics in the University at Buffalo School of Medicine and Biomedical Sciences stated, “We have examined the molecular mechanism underlying gender-specific effects of stress. Previous studies have found that females are more resilient to chronic stress and now our research has found the reason why.”

Animal study
In an effort to find a scientific explanation as to why women are better at combating stress, researchers devised an animal study. They subjected young male and female rodents to tasks mimicking challenging experiences often faced by humans, such as those causing frustration and feelings of pressure.

This was achieved by placing the animals in a small cylindrical compartment for two hours daily for roughly a period of one -week.

To assess the animals’ short-term memory, the rats were presented with two identical objects, followed by a second pair an hour later. Three hours later, animals were again shown one object from each pair. (An inability to recall a familiar object indicates disturbance in the brain region that controls working memory, attention, decision-making and other high-level ‘executive’ processes).

Revelations of the study
It was noted that female rats despite being exposed to periodic physical restraint were able to remember and recognize objects they had previously been shown. In contrast, short term memory of male rats subjected to the same stress was impaired.

The investigators found the prefrontal cortex of young males exposed to stress exhibited a loss of glutamate receptors while there was no change in glutamate receptor numbers in female rats.
However, when male mice were administered the female sex hormone oestrogen, the scientists found they showed more flexibility under pressure.

Dr Yan stated, “When oestrogen signalling in the brains of females was blocked, stress exhibited detrimental effects on them. When oestrogen signalling was activated in males, the detrimental effects of stress were blocked.

“We still found the protective effect of oestrogen in female rats whose ovaries were removed. It suggests that it might be oestrogen produced in the brain that protects against the detrimental effects of stress.”

Therapeutic potential unearthed
Given that the animal study shows promise, experts are optimistic that the findings may hold relevance for humans since many cellular functions are similar between the two species.

“If we could find compounds similar to oestrogen that could be administered without causing hormonal side effects, they could prove to be a very effective treatment for stress-related problems in males,” Dr Yan said.

The study sponsored by the National Institute of Mental Health of the National Institutes of Health has been published in Molecular Psychiatry.