“Tobacco/Smoking kills” or “Tobacco/smoking is injurious to health” we all know these slogans. Any kind of tobacco products are bad for our health and even the new e-cigarettes may have harmful toxins.
What is nicotine?
Nicotine is a potent parasympathomimetic alkaloid found in the nightshade family of plants (Solanaceae) and is a stimulant drug. Nicotine is a nicotinic acetylcholine receptor (nAChR) agonist, except at nAChRα9 and nAChRα10 where it acts as an antagonist. Nicotine is found in the leaves of Nicotiana rusticain amounts of 2–14%, the tobacco plant Nicotiana tabacum, Duboisiahopwoodii and Asclepias syriaca.
It constitutes approximately 0.6–3.0% of the dry weight of tobacco and is present in the range of 2–7 µg/kg of various edible plants. It functions as an antiherbivore chemical; consequently, nicotine was widely used as an insecticide in the past and neonicotinoids such as imidacloprid are currently widely used.
Nicotine is highly addictive (see nicotine dependence). An average cigarette yields about 2 mg of absorbed nicotine,and in lesser doses of that order, the substance acts as a stimulant in mammals,while high amounts (50–100 mg) can be harmful.
The primary therapeutic use of nicotine is in treating nicotine dependence in order to eliminate smoking with the damage it does to health. Controlled levels of nicotine are given to patients through gums, dermal patches, lozenges, electronic/substitute cigarettes or nasal sprays in an effort to wean them off their dependence
Nicotine is frequently used for its performance-enhancing effects on cognition, alertness, and focus.A meta-analysis of 41 double-blind, placebo-controlled studies concluded that nicotine or smoking had significant positive effects on aspects of fine motor abilities, alerting and orienting attention, and episodic and working memory.
Nicotine may work as anti-aging element the new study
According to the new research at Texas A&M, it turns out the 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. So tobacco’s nicotine can work as brain’s anti-aging element.
The research team leader Dr. Ursula Winzer-Serhan, an associate professor at the Texas A&M College of Medicine, and colleagues report their findings in the “Journal of Toxicology”.
The past animal and human studies have shown that nicotine has possible cognitive benefits; the chemical binds to and activates nicotinic acetylcholine receptors(nAChRs) in the brain, which has been found to reduce neurodegeneration.
"Thus,medicinal use of nicotine or related nAChR agonists could have great beneficial effects for human health," the authors note.
However,the underlying mechanisms of this association are unclear, and given nicotine's well-known addictive properties, it is no surprise that concerns have been raised about using the chemical as a treatment for neurodegenerative disorders.
Dr.Winzer-Serhan and team used mouse models for their research work to investigate the effects of nicotine at various doses on appetite, weight, anxiety, and levels of nAChRs in the brain.
"Some people say that nicotine decreases anxiety, which is why people smoke, but others say it increases anxiety," Winzer-Serhan said. "The last thing you would want in a drug that is given chronically would be a negative change in behavior. Luckily, we didn't find any evidence of anxiety: Only two measures showed any effect even with high levels of nicotine, and if anything, nicotine made animal models less anxious.” he also adds.
Excessive nicotine dose and anxiety relation
Nicotine was added to the drinking water of mice at either low, medium, or high doses, the scientist team said to their report.
On assessing the mice that received low and medium doses of nicotine, the researchers identified no traces of the drug in their blood, and there were no changes in food intake, weight, or nAChRs.
However, mice that received the high nicotine dose,showed a reduction in food intake and body weight and an increase in nAChR levels. Additionally, the researchers identified no signs of increased anxiety in the high-dose mice.
Yet,the current results indicate that nicotine treatment is unlikely to alter behavior, bringing researcher’s one step closer to determining the safety of nicotine as a treatment for neurodegenerative disorders.
The researchers say they plan to conduct further studies to investigate the effects of nicotine against neurodegeneration in aged mice, and they also want to determine whether nicotine's ability to reduce appetite and weight gain explains its possible protective effect against brain aging.
By saying this, Dr. Winzer-Serhan stresses that their findings should not encourage the use of cigarettes and other nicotine-containing products.
"At the end of the day, we haven't proven that this addictive drug is safe - and it certainly isn't during childhood or adolescence - or that the benefits outweigh the potential risks," she adds.
"Even if these weren't very preliminary results, smoking results in so many health problems that any possible benefit of the nicotine would be more than canceled out.
However,smoking is only one possible route of administration of the drug, and our work shows that we shouldn't write-off nicotine completely, “Says Dr. Ursula Winzer-Serhan.