Gender equality may work on a social scale but when it comes to biological processes, men and women are dramatically unequal, as recent study shows. The research was performed on mice that showed different, gender-specific responses when exposed to pain stimuli.
The main focus of researchers was microglia, a particular immune cell that can be found in the brain and spinal cord. These cells play a giant role in the realm of pain experience, increasing or decreasing the levels at which we feel and deal with pain.
The genetic study performed on mice revealed that microglia is not as important in the pain cycle of female mice, compared to male subjects. To strengthen the findings, scientists decided to find out if juggling with the cell would have similar effects both in male and female mice.
Female mice experience pain at a higher level
When injury or inflammation occurs, the signal triggered by microglia makes the body vulnerable in front of pain, so that even a light touch could hurt. Researchers used mice that were suffering from a high sensitivity to pain. Before reaching conclusions, scientists offered both male and female subjects drugs that target the microglial cells, hoping to prevent the animals from feeling pain. It seems that only male mice responded to the treatment, while female study subjects still showed high sensitivity to pain.
The team of researchers first of all induced almost unbearable pain in healthy male and female mice, by severing sciatic nerve branches in their posterior paws. After a week, they injected drugs to inhibit microglial function.
Mice were treated with three types of drugs, aimed at reversing pain sensation for both genders. The treatments had no effect on females, although both groups of animals were experiencing equivalent levels of pain.
After repeated experiments, exposing mice to different levels and types of pain, researchers concluded that male mice failed to feel pain after being subjected to treatments, whereas female mice still did. The finding lead them to believe that microglia doesn’t seem to have much to do with the way female mice experience pain. Females probably have a yet unknown biological inner working that reacts to diverse pain inhibitors.
Open doors for better chronic pain treatments
Chronic pain is known to affect more than 100 million people in the US. Chronic pain is more popular than cancer, heart disease and diabetes altogether. Women are more exposed to pain conditions compared to men. Menstruation only brings unbearable pain and it happens on a monthly basis for women. Migraines are also more popular among women, along with back pain.
Figuring out how male and female mice deal with pain could lead to the development better tailored pain treatments.
Research needs improvement on a large scale
“If people that had researched microglia 15 years ago had been using male and female mice, they would have noticed the difference instantly”. Levels at which pain Is experienced are gender-specific.
When it comes to studies performed on animals, scientists concentrate on gathering mostly male subjects. Researchers “have spent all their time and all their efforts studying male rodents exclusively”, thus limiting the diversity of knowledge dramatically.
Bucking the entire history of using exclusively males for lab experiments could help improvement in pain research in particular and scientific research on a large scale from beginning stages. Research funding agencies are already supporting the initiative to balance the representation of sexes across all research studies.
Scientists often exclude female animals from their studies, stating that menstruation could make data unstable. Generally, male animals are used more often in medical research, despite the fact that men and women react differently to drugs.
The biological differences could explain why many clinical trials of pain treatments have failed, highlighting the shortcomings in the manner that researchers envision their experiments.
Image Source: cannabishealth.com
