Correlation between smokeless tobacco (Gutkha) and biomarkers of oxidative stress in plasma with cardiovascular effects

Tobacco products are widely consumed around the world in smoking and smokeless tobacco (SLT) forms. Analysis of smokeless tobacco consumption suggested that the effects of nicotine and tobacco-specific N-nitrosamines, the main ingredients of smokeless tobacco are attractive to study because its consumption often results in biochemical changes of plasma parameters and markers of oxidative stress development. Smokeless tobacco users generally consume the most commonly available SLT products like khaleja brand of gutkha and mahak chaini brand of khaini 3-5 times per day. We found a significant increase in plasma glucose levels, total cholesterol, triglycerides, and a significant decrease in high-density lipoprotein (HDL) cholesterol indicative of atherosclerosis risk. We also found that the plasma peroxynitrites (ONOO-), nitric oxide (NO), lipid peroxidation (LPO), and protein carbonyls (PCO) levels were significantly elevated. Plasma nicotine and cotinine levels were significantly elevated in study subjects, suggesting that nicotine could be responsible for the oxidative and nitrosative stress indirectly inducing cardiovascular risk. There was a strong correlation of nicotine with reactive oxygen species (ROS), reactive nitrogen species (RNS), cholesterol, and creatinine in exposed smokeless tobacco (gutkha) consumers. These data demonstrate SLT users are at high cardiovascular risk due to nicotine-induced free radicals and oxidative damage.