Using Phytochemicals to Investigate the Activation of Nicotine Detoxification via Upregulation of CYP2A6 in Animal Models Exposed Tobacco Smoke Condensate by Intratracheal Instillation

This study examined the efficacy of standardized Smilax china L. root extract (SSCR) containing chlorogenic acid on detoxifying nicotine from tobacco smoke condensate (TSC) in vitro and in vivo. Chlorogenic acid is an identified bioactive component in SSCR by ultraperformance liquid chromatography/photodiode array/electrospray ionization/mass spectroscopy (UPLC/PDA/ESI/MS). HepG2 liver cells and A549 lung cells were carried for measuring ROS and antioxidant enzymes. Sprague-Dawley rats were treated with nicotine by intratracheal instillation (ITI). Cell viabilities by pretreatments of 5, 12.5, and 25, 50 μg SSCR/mL ranged from 41 to 76% in HepG2 and 65 to 95% in A549. Pretreatments of SSCR inhibited TSC-mediated production of reactive oxygen species (ROS) by 8 and 10% in HepG2 and A549 cells, respectively. However, the expression of CAT, SOD1, and AOX1 was downregulated by SSCR in the both cells. The highest conversion of cotinine was observed at 50 μg/mL of SSCR after 120 min of incubation. SSCR upregulated CYP2A6 3-fold in A549 cells regardless of TSC cotreatment. When Sprague-Dawley rats were treated with nicotine by ITI or subjected to SSCR administration for 14 days, the levels of cotinine in urine increased in SSCR treatment only. The cellular level of antioxidant capacity at 10 or 100 mg/kg body weight/day of SSCR treatment was 1.89 and 1.86 times higher than those of nicotine-control. Results suggest that the intake of SSCR can detoxify nicotine by elevating nicotine conversion to cotinine and antioxidant capacity.

Characterization of Toxic Metals in Tobacco, Tobacco Smoke, and Cigarette Ash from Selected Imported and Local Brands in Pakistan

In this study, concentrations of Cd, Ni, Pb, and Cr were determined in tobacco, tobacco smoke-condensate, and cigarette ash for selected brands used in Pakistan. Smoking apparatus was designed for metal extraction from cigarette smoke. Samples were digested through microwave digester and then analyzed by flame atomic absorption spectrophotometer (FAAS). Higher concentration of Ni was detected in imported brands than the counterparts in the local brands. Pb levels were however higher in local brands while significant concentration of Cd was observed in both brands. For Cr, the level in tobacco of local brands was higher than their emitted smoke, whereas imported brands showed higher level in smoke than in tobacco. The cigarette ash retained 65 to 75% of the metal and about 25 to 30% went into the body. While this study revealed the serious requirement to standardize the manufacturing of tobacco products, more importantly is the urgent need for stronger enforcements to put in place to alert the general population about the hazardous effects of cigarettes and the health risks associated with these toxic metals.