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.

中文翻译：

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吸烟，饮食和帕金森病引起的尼古丁：综述。

流行病学研究的证据表明，吸烟与帕金森病（PD）的低风险之间存在关联。作为烟草烟雾的主要成分，有人提出尼古丁是一种预防PD风险的物质，在调节通过多巴胺能系统介导的纹状体活动和行为中起关键作用。动物研究还表明，尼古丁可以调节多巴胺的传递并减少左旋多巴引起的运动障碍。但是，先前的临床试验在尼古丁治疗方面产生了有争议的结果。在这篇综述中，我们更新了流行病学，临床前和临床数据，以及饮食中尼古丁的研究。我们还回顾了遗传因素与吸烟之间的相互作用。由于少量的尼古丁会使大脑中的大部分尼古丁受体饱和，