Mitochondria are the crossroads of several crucial cellular activities; they produce considerable quantities of superoxide radical and hydrogen peroxide, which can damage important macromolecules. Nicotine affects a variety of cellular processes, from induction of gene expression to modulation of enzymatic activities. The aim of this study was to elucidate the protective effects of andrographolide (ANDRO) aqueous extract (AE-Ap) of Andrographis paniculata, and vitamin E on nicotine-induced brain mitochondria. In this investigation, nicotine (1 mg.kg body mass-1.day-1) was treated, for the period of 7 days, simultaneously with 2 A. paniculata products, ANDRO and AE-Ap (250 mg.kg body mass-1.day-1); and vitamin E (50 mg.kg body mass-1.day-1) was supplemented in different group of male Wistar rats. The activities of mitochondrial electron transport chain (Mito-ETC) complexes (I, II, III), nitric oxide production, superoxide anion, catalase, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, and concentrations of reduced glutathione and oxidized glutathione were measured in discrete regions of brain (the cerebral hemisphere, cerebellum, diencephalons, and brain stem). The study revealed that nicotine inhibits the Mito-ETC complexes and produces nitric oxide, which suppressed the mitochondrial oxidative stress scavenger system in different brain regions. In these circumstances, lipid peroxidation and protein oxidation were noted in different discrete regions of brain mitochondria. ANDRO, AE-Ap, and vitamin E showed the protective potentiality against nicotine toxicity. The analysis of such alterations is important in determining the basis of normal dysfunction in the brain associated with nicotine toxicity, which could be ameliorated by A. paniculata and vitamin E, and may help to develop therapeutic means against nicotine-induced disorders.

Lymphocytes are an important immunological cell and have been played a significant role in acquired immune system; hence, may play in pivotal role in immunosenescence. Oxidative stress has been reported to increase in elderly subjects, possibly arising from an uncontrolled production of free radicals with aging and decreased antioxidant defenses. This study was aimed to evaluate the level of lipid-protein damage and antioxidant status in lymphocytes of healthy individuals to correlate between oxidative damage with the aging process. Twenty healthy individuals of each age group (11–20; 21–30; 31–40; 41–50; and 51–60 years) were selected randomly. Blood samples were drawn by medical practitioner and lymphocytes were isolated from blood samples. Malondialdehyde (MDA), protein carbonyls (PC) level were evaluated to determine the lipid and protein damage in lymphocytes. Superoxide dismutase (SOD), catalase (CAT), glutathione and glutathione dependent enzymes were estimated to evaluate the antioxidant status in the lymphocytes. Increased MDA and PC levels strongly support the increased oxidative damage in elderly subject than young subjects. The results indicated that, balance of oxidant and antioxidant systems in lymphocytes shifts in favor of accelerated oxidative damage during aging. Thus oxidative stress in lymphocytes may particular interest in aging and may play important role in immunosenescence.

The immune cells use reactive oxygen species (ROS) for carrying out their normal functions while an excess amount of ROS can attack cellular components that lead to cell damage. In the present study, peritoneal macrophages (6 x 10(6) cells, >95% viable) isolated from male Swiss mice were treated with nicotine (1 mM, 5 mM, 10 mM, 25 mM, and 50 mM) in vitro for 12 h and the superoxide anion generation, lipid peroxidation, protein oxidation and antioxidant enzymes status were monitored. Maximum superoxide radical generation was found at the dose of 10 mM nicotine. The lipid peroxidation and protein oxidation were increased significantly (p < 0.05) along with the increasing dose of nicotine. The reduced glutathione level, catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase activities were decreased significantly (p < 0.05), and oxidized glutathione level was increased significantly (p < 0.05) with the increasing dose of the nicotine. From these experiments, it was also observed that all the changes in peritoneal macrophages with 10 mM, 25 mM, and 50 mM nicotine had no significant difference. To observe the effect of nicotine in vivo, this study examined the liver and spleen antioxidant status after nicotine administration (1 mg/kg BW) intraperitoneally in mice and found the diminished SOD activity and GSH level. It may be concluded that nicotine is able to enhance the production of ROS that produced oxidative stress in murine peritoneal macrophages. It also suggested that, 10 mM in vitro nicotine treatment for 12 h is the effective dose.

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We conclude that oxidative stress is due to the enhanced lipid peroxidation and decrease in antioxidant enzymes, and it can be restored with dietary supplementation of L-glutamine related drug.