Associate Professor Erika Comasco, the study’s principal investigator from Uppsala University in Sweden, stated: “For the first time, we can observe that nicotine functions to shut off the estrogen production pathway in women’s brains. We were shocked to learn that this impact could be observed with just one nicotine dosage, or the equivalent of just one cigarette, demonstrating the potency of smoking’s effects on a woman’s brain. This phenomenon is brand-new, and research on it is still in its early stages.
Although nicotine operates in this region of the brain, we are yet unsure of the behavioural or cognitive consequences. Nevertheless, we highlight that the impacted brain system is a target for addictive substances, such as nicotine. The impact has been shown in the thalamus, a portion of the limbic system of the brain. This system has a role in controlling emotions and behaviour.
Researchers from Uppsala University in Sweden assisted ten healthy female volunteers who took part in the study. The ladies also got an injection of a radioactive tracer coupled to an enzyme called aromatase, sometimes known as estrogen synthase, which binds to estrogen, along with an intranasal dosage of nicotine from a commercial supplier. Estrogen is made by the enzyme aromatase.
Using MRI and PET brain imaging, the researchers were able to see where and how much aromatase was located in the brain. The amount of brain-based aromatase was shown to be somewhat lowered by a single dosage.
Men and women respond to nicotine differently, and it has long been known that women are more resistant to NRT and more prone to relapse when attempting to quit smoking than men. Uncertainty exists regarding the biological causes of these variances. This is the first time that human aromatase synthesis has been prevented. The effect on men was not examined.
Continued Professor Comasco “This finding suggests that nicotine’s impact on estrogen production affects the brain significantly, albeit it’s unclear if it also affects other processes like the reproductive system. Men and women react to smoking in very different ways, and these variations are substantial. Women appear to be less likely to respond to NRT, have more relapses, have more susceptibility to smoking’s heritability, and are more likely to suffer from primary smoking-related disorders such as lung cancer and heart attacks. We must now determine if nicotine’s impact on the hormone system plays a role in any of these reactions.”
“This is undoubtedly a significant initial result,” stated Professor Wim van den Brink, Emeritus Professor of Psychiatry and Addiction at the Academic Medical Center, University of Amsterdam. Smoking has numerous harmful consequences on both men and women, but it was not previously recognised that nicotine might reduce the synthesis of estrogen in females. However, it should be recognised that tobacco addiction is a complicated condition with several underlying causes. It’s unclear that this particular nicotine impact on the thalamus (and the synthesis of estrogen) accounts for all of the documented variations between male and female smokers in terms of development, treatment, and results.
Although there is still a long way to go before female cigarette smokers have a decreased risk of nicotine addiction, adverse treatment effects, or relapse, this work warrants additional study.