Testosterone And Other Sex Hormones Impact Asthma Response Dependent On Sex

Many conditions affect men and women differently. One of these conditions is asthma. It has long been known that pre-pubertal males tend to have more issues with asthma than females of the same age, but the underlying reasons have not been so straightforward.

Recently, researchers from Johns Hopkins have explored the effects of Testosterone on asthma. Understanding how men and women differ physiologically is critical because it leads to different risks and factors impacting potential treatment options.

While this study was conducted in mice, its results are hypothesized to be transferrable to humans. The research was published in the Journal of Immunology last October. While women are less likely to experience asthma than men in adulthood, Testosterone activates inflammation receptors in the lungs in response to exposure to an allergen known as ovalbumin. These results give some mixed messages.

Asthma Risk Dependent on Age and Sex

Asthma is attractive because its prevalence changes among males and females depending on age. Before puberty, boys are more liable to have issues with asthma than girls. After puberty, however, the situation changes. Then girls and women are more likely to have asthma. This is an example of how sex hormones lead to wellness-related sex differences. We can improve asthma diagnosis and treatment protocols by exploring the mechanisms behind these differences.

A previous study investigated how Estrogen affected lung inflammation in mice. They found that Estrogen triggers inflammation. As we mentioned earlier, post-pubertal girls and women have a much higher incidence of asthma than men of the same age.

This data led researchers to hypothesize that Testosterone would provide benefits against lung inflammation. For example, while still in the experimental phases, male hormones have been prescribed as a successful treatment for women with asthma.

Mouse Testosterone Asthma Study

To learn more about how Testosterone impacts asthma, researchers needed mice that couldn't produce their sex hormones. Using castrated mice could precisely control hormone levels using Testosterone Implants, which slowly and steadily release hormones.

Researchers also had to simulate asthmatic allergic reactions in the mice because mice don't typically experience allergic asthma. Researchers aerosolized albumin to trigger a lung reaction similar to what humans experience with an asthma attack.

Testosterone and Lung Inflammation

Lung Inflammation is triggered by specific immune cells known as Alveolar Macrophages. These microscopic phagocytes absorb and break down debris in the lungs. They also trigger inflammatory activity, including the cascade of symptoms associated with an asthma attack. Researchers expected Testosterone to protect against lung inflammation in the mice.

What they discovered was more complicated. While Testosterone suppressed most markers of inflammation, it activated lung inflammation, specifically in Alveolar Macrophages. Researchers then bred male/female mice without Testosterone Receptors in their Alveolar Macrophages.

Here, they discovered a critical sex difference. Male mice had less inflammation when these receptors were deactivated. Female mice saw no such change. This means that in male mice, Testosterone is more intricately involved in how irritants trigger asthma responses.

This provides evidence that testosterone can help women with asthma, but those results are sex-specific. This research highlights that a person's characteristics are essential when considering treatment options.

Research like this will likely lead to treatment options that differ for men and women. While an asthma attack looks the same in males and females, the mechanisms which trigger the attack differ, which provides different opportunities for ideal treatment. Antihistamines and Steroids are the go-to treatment for asthma, but males with severe asthma may benefit more from alternative therapy.

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