Science and medicine are complicated enough without people muddying the waters with unfounded claims. This is why I am particularly annoyed with a press release that tries to suggest that a Texas A&M study shows nicotine as having potential protective effects for the aging brain. The line in question is not ambiguous about this point, either: “…according to research at Texas A&M, it turns out that nicotine itself—when given independently from tobacco—could help protect the brain as it ages, and even ward off Parkinson’s or Alzheimer’s disease.”
There are only two words that can describe such a claim: categorically false. The study looked at the effects of nicotine administration, but nothing in the findings or conclusion suggests anything close to this particular claim.
In Brief: Mouse Nicotine Models
Cigarettes, even e-cigarettes, are bad for your health due to the harmful chemicals they emit. Despite this, there is some research suggesting that nicotine on its own may have neuroprotective effects. However, testing this in an animal model is tricky. Studying nicotine administration for this purpose would require long-term dosing. Using nicotine-laced water was proposed as a non-invasive and low-stress option that doesn’t require additional animal handling; unfortunately, this approach comes with certain hitches. The bioavailability of nicotine—the amount that actually gets absorbed by the body—is low when taken orally. Mice also metabolize nicotine rather quickly, which adds further challenge to finding an effective dose.
The Texas A&M study was an attempt to see if an effective oral dosing of nicotine could be found for mice. It did not make any attempt to assess anything about anti-aging effects or brain protection.
What the Study Actually Found
There are several known effects of nicotine consumption. Two hallmarks are appetite suppression (plus subsequent weight or BMI loss) and an increase in certain binding sites within the brain. These markers, as well as certain blood measurements, would be used to see if different levels of nicotine water could produce effects of chronic nicotine exposure in mice. If these effects appeared, then it would suggest the dosing method to be potentially usable in future neuroprotection studies.
The mice were divided into four groups, a control plus a low, medium, and high nicotine concentration group. Each level was meant to correspond with occasional, low, and medium smokers, respectively. The low and medium nicotine groups did not show any changes in food intake, body weight or body mass index, brain receptors, or in blood markers. The high group, however, did. At this level, the mice showed noticeable appetite suppression, weight loss, increase in receptors, and displayed some of the higher blood measurements. The findings related to appetite and weight loss in particular seem to be supported by prior research in this field, which adds to its potential validity.
What This Means
High concentrations of nicotine water may be an effective way to administer nicotine to mice for the purposes of assessing the substance’s impact on the aging brain. However, nothing about the study suggests, or even tries to investigate, nicotine as being able to “protect the brain as it ages”. Such claims obscure the actual results of the study and should be condemned.
“Can Nicotine Protect the Aging Brain?” Vital Record web site, September 20, 2016; https://vitalrecord.tamhsc.edu/can-nicotine-protect-the-aging-brain/?_ga=1.85355289.140298309.1471458860, last accessed September 21, 2016.
Huang, P., et al., “Evaluation of Chronic Oral Nicotine Treatment in Food Consumption, Body Weight and [125I] Epibatidine Binding in Adult Mice,” Open Access Journal of Toxicology, 2016; OAJT.MS.ID.555552.