Smokeless tobacco induced biophysical and biochemical alterations in the plasma, erythrocytes, and platelets of panmasala users: Subsequent biological effects

Aim & background: Smokeless tobacco (SLT) products are extensively consumed throughout the world including India. These products act as the primary addictive agents, due to the presence of nicotine among other tobacco products to humans and animals and its quitting is difficult. Higher the exposure of SLT products more is the toxic effects and alterations in erythrocytes and platelets.

Objectives: The products of smokeless tobacco could cause increase in the concentrations of oxidants (free radicals), decrease the activities antioxidant enzymes, activate the process of programmed cell death through enhanced expression of inducible nitric oxide synthase. Smokeless tobacco products represent a major modifiable risk factor for the development of redox imbalance through the enhanced production of reactive oxygen species and diminished activities of antioxidant enzymes in plasma, bio-membranes of erythrocytes, and platelets and induction of apoptosis in the blood.

Materials and methods: The protein expression of inducible nitric oxide synthase (iNOS) was studied by western blot and gene expression of apoptotic proteins, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) was evaluated by RT-PCR technique. Membrane fluidity of erythrocytes and platelets was studied by the fluorescence method.

Results: The results of the present study revealed that significantly elevated levels of iNOS enzyme in plasma, erythrocyte, and platelet membranes of panmasala users. We found that gene expression levels of Bcl₂, Bax, IL-6, caspase proteins (Caspase 8, Caspase 10, and Caspase 12) are greater and decreased levels of TNF-α with no significant change in blood of smokeless tobacco users in comparison with normal controls. In addition, there were substantial significantly higher in concentrations of nicotine, cotinine, and epinephrine in the plasma of panmasala users than non-tobacco users. Panmasala can be caused a significant increase in nitroxidative stress marker (LPO, NO, and ONOO^-) values and significant decrease in the levels of antioxidant enzymes in erythrocytes and platelets.

Conclusion: On the basis of the present study results, it may be concluded that the chronic use of panmasala than any smokeless tobacco products may be a contributory risk factor or may give conclusive idea and has been associated with the expansion of the development of structural and functional alterations in the erythrocyte and platelet membranes induced oxidative damage and apoptosis, possibly further enhanced by nicotine and tobacco-specific N-nitrosamines. SLT exposure had implicated a threat and enormous implications on public health and is required to prove that may not be viewed as a safe alternative to any tobacco products.

Keywords: Apoptosis; Chronic toxicity; Inducible nitric oxide synthase; Membranes; Smokeless tobacco.