The Pharmacological Actions of Nicotine on the Gastrointestinal Tract

Abstract

Abstract. Increasing use of tobacco and its related health problems are a great concern in the world. Recent epidemiological findings have demonstrated the positive association between cigarette smoking and several gastrointestinal (GI) diseases, including peptic ulcer and cancers. Interestingly, smoking also modifies the disease course of ulcerative colitis (UC). Nicotine, a major component of cigarette smoke, seems to mediate some of the actions of cigarette smoking on the pathogenesis of GI disorders. Nicotine worsens the detrimental effects of aggressive factors and attenuates the protective actions of defensive factors in the processes of development and repair of gastric ulceration. Nicotine also takes part in the initiation and promotion of carcinogenesis in the GI tract. In this regard, nicotine and its metabolites are found to be mutagenic and have the ability to modulate cell proliferation, apoptosis, and angiogenesis during tumoriogenesis through specific receptors and signalling pathways. However, to elucidate this complex pathogenic mechanism, further study at the molecular level is warranted. In contrast, findings of clinical trials give promising results on the use of nicotine as an adjuvant therapy for UC. The beneficial effect of nicotine on UC seems to be mediated through multiple mechanisms. More clinical studies are needed to establish the therapeutic value of nicotine in this disease.

Role of Helicobacter Pylori Infection and Lifestyle Habits in the Development of Gastroduodenal Diseases in a Population From the Brazilian Amazon

“…However, no association was observed with excessive alcohol consumption. Epidemiological studies suggest that alcohol plays a fundamental role in the development of gastrointestinal diseases such as peptic ulcer and gastric cancer since it causes gastric mucosal injuries and stimulates parietal cells to produce gastric acid, in addition to its synergistic action with smoking (5,29) . Inadequate dietary habits such as excess intake of salt, preservatives and smoked produced, as well as diets poor in vegetable and fruits, are also strongly associated with the development of gastric cancer (24,28) .…”

Colorectal cancer occurs earlier in those exposed to tobacco smoke: implications for screening

“…In two current studies, Wong demonstrated in the first study that nicotine promoted human colon adenocarcinoma cell proliferation and in the other study that nicotine promoted colon tumor growth and angiogenesis (Wong et al 2007a(Wong et al [k1], 2007b. Other researchers have concluded that nicotine may at least be partially involved in the initiation, promotion and progression of gastrointestinal tumors (Wu and Cho 2004).…”

4-(Methylnitrosamino)-1-(3-Pyridyl)-1-Butanone from Cigarette Smoke Stimulates Colon Cancer Growth via β-Adrenoceptors

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