Effects of isolated tobacco alkaloids and tobacco products on deprivation-induced food intake and meal patterns in rats

Abstract

The ability of smoking to reduce body weight serves as motivation for continued smoking. It is unclear to what extent non-nicotine constituents in cigarettes are contributing to the weight-reducing effect of smoking. The purpose of the current study was to examine the effects of nicotine and four minor tobacco alkaloids (nornicotine, cotinine, anatabine, and anabasine) on food intake, one of the key regulators of body weight. In addition, a smokeless tobacco extract (STE) and e-cigarette (EC) refill liquid were used to model the effects of actual tobacco product exposure on food intake. Male Holztman rats were trained to lever press for food pellets during daily 2h sessions in operant chambers. In Experiment 1, the effects of subcutaneous injections of saline, nicotine (0.25-1.00mg/kg), nornicotine (0.50-6.00mg/kg), cotinine (1.00-100.00mg/kg), anatabine (0.25-3.00mg/kg), and anabasine (0.50-4.00mg/kg) were assessed. In Experiment 2, rats from Experiment 1 were used to examine the effects of nicotine, STE, and EC liquid. All alkaloids, except cotinine, produced a dose-dependent reduction in overall food intake. The highest doses of all drugs significantly reduced latency and response rate to obtain the first pellet. At some doses, nicotine, anatabine, and nornicotine reduced food intake within the first 45min without compensatory increases in intake later in the session. STE and EC liquid produced dose dependent decreases in food intake similar to nicotine alone. These data suggest that minor tobacco alkaloids have appetite suppressant effects and warrant further investigation into their effects on body weight, energy intake, and energy expenditure under free-feeding conditions. However, findings with STE and EC liquid suggest that nicotine is the primary constituent in these products to affect food intake, whereas levels of minor alkaloids in these products may be too low to influence food intake.

Effects of nicotine and THC vapor inhalation administered by an electronic nicotine delivery system (ENDS) in male rats

“…There are as yet relatively few studies of the effects of ENDS in rodent models, however, recent studies showed e-cigarette based vapor inhalation of nicotine in mice reduced body temperature and locomotor activity (Lefever et al, 2017) and increased platelet activity (Qasim et al, 2018), which together demonstrate the feasibility of the approach. The paucity of models is underlined by the fact that several recent studies have resorted to parenteral injection of e-cigarette refill liquids to determine effects in rats (Bunney et al, 2018;El Golli et al, 2016;Golli et al, 2016;Harris et al, 2015;LeSage et al, 2016). Inhalation administration of nicotine is possible since one study showed that inhalation of air bubbled through an aqueous solution of nicotine produces nicotine dependence and facilitates the acquisition of subsequent nicotine intravenous self-administration (Gilpin et al, 2014).…”

Effects of Nicotine and THC Vapor Inhalation Administered by An Electronic Nicotine Delivery System (ENDS) in Male Rats

“…There are as yet relatively few studies of the effects of ENDS in rodent models, however recent studies showed e-cigarette based vapor inhalation of nicotine in mice reduced body temperature and locomotor activity (Lefever et al 2017) and increased platelet activity (Qasim et al 2018), which together demonstrate the feasibility of the approach. The paucity of models is underlined by the fact that several recent studies have resorted to parenteral injection of e-cigarette refill liquids to determine effects in rats (Bunney et al 2018;El Golli et al 2016;Golli et al 2016;Harris et al 2015;LeSage et al 2016). Inhalation administration of nicotine is possible, since one study showed that inhalation of air bubbled through an aqueous solution of nicotine produces nicotine dependence and facilitates the acquisition of subsequent nicotine intravenous self-administration (Gilpin et al 2014).…”

Addiction of tobacco chewing and smoking in the patients of head and neck squamous cell carcinoma: A descriptive epidemiological study in Pakistan

“…20,000/month. It has been reported that nicotine in tobacco reduces the appetite12, so people with low incomes might use tobacco products to suppress their appetites, ultimately leading to the development of HNSCC.…”