Nicotine from cigarette smoking and diet and Parkinson disease: a review

Abstract

Evidence from epidemiological studies suggest a relationship between cigarette smoking and low risk of Parkinson disease (PD). As a major component of tobacco smoke, nicotine has been proposed to be a substance for preventing against PD risk, with a key role in regulating striatal activity and behaviors mediated through the dopaminergic system. Animal studies also showed that nicotine could modulate dopamine transmission and reduce levodopa-induced dyskinesias. However, previous clinical trials yield controversial results regarding nicotine treatment. In this review, we updated epidemiological, preclinical and clinical data, and studies on nicotine from diet. We also reviewed interactions between genetic factors and cigarette smoking. As a small amount of nicotine can saturate a substantial portion of nicotine receptors in the brain, nicotine from other sources, such as diet, could be a promising therapeutic substance for protection against PD.

Keywords: Diet; Gene-environment interactions; Nicotine; Parkinson disease; Smoking.

Fig. 1

Parkinson disease risk associated with each additional serving of edible Solanaceaea and other vegetables [86]. ^a Among never-used-tobacco participants (241 PD cases and 239 controls) in a case-control study in western Washington State.^b All assessed edible Solanaceae: green, yellow or red peppers, tomatoes, tomato juice, and baked or mashed potatoes. ^e Relative risk (odds ratio) and 95% confidence interval, per once daily increase in typical adult life frequency of consumption, adjusted for age (continuous), sex, race/ethnicity, consumption of other vegetables (continuous) and caffeine (mg, continuous); and adjustment for or stratification by tobacco use (ever vs. never >100 cigarettes or regularly used cigars, pipes or smokeless tobacco). ^d All assessed non-Solanaceae vegetables combined: broccoli, cauliflower, cabbage, Brussels sprouts, radishes, lettuce, spinach/other greens, carrots, peas/lima beans, corn, sweet potatoes/yams, cucumbers, zucchini, yellow/winter squash and onions/scallions. ^c Median dry-weight nicotine concentration in each Solanaceae as typically consumed (e.g. ripe tomatoes and cooked potatoes) [116]