Objective: Exposed to cigarette leads to the formation of reactive oxygen species and the generation of bioactive molecules that can damage skin cells. This investigation was carried out to study possible effects of Alpha Lipoic Acid (ALA) on smoking-induced rat skin injury.
Materials and methods: 28 Spraque-Dawley female rats were allocated into three groups: control group (n = 8), smoking group (n = 10; 12 cigarettes/day, 8 weeks) and smoking + ALA group (n = 10; 12 cigarettes/day + 100 mg/kg, 8 weeks). Experiment group animals were sacrificed under anaesthesia with 10%ketamine + 2%xylasine at the end of second mounts and then skin examples were taken from the epigastric area. Histochemical (Haematoxylin-Eosin and Masson's trichrome, immunohistochemical (TNF-α) and biochemical analysis (CAT, MDA and protein carbonylation) were performed on these skin tissues.
Results: Histologically, skin was distinguished normal structure in the control group. In the smoking group, collagen bundles and hair follicle degradation/reduction, sweat gland degeneration, mononuclear cell infiltration in dermis were encountered. In ALA-treated group, all of these changes were improved (p < 0.05). Collagen bundles structures were appearance more regular than the smoking group . Immunohistologically, intense staining was observed in the smoking group, while very weak staining was observed in control group, weak staining was observed in the ALA-treated group. Biochemically; The CAT activity compared to cigarette group with control was raised high and in ALA group was higher compared to both groups, but not significant (p > 0.05). MDA; which is indicator of lipid peroxidation was significantly higher in cigarette group than in control group (p < 0.05) and was significantly lower in ALA group than cigarette (p < 0.05). Protein carbonylation was higher in cigarette group than the control group but not in the non-significant (p > 0.05). In the ALA it was significantly lower compared to the control group and cigarette (p < 0.05).
Conclusions: Based on biochemical and histopathological determinations, the study showed that cigarette smoke can cause degenerative effects on skin tissues in rats. However, ALA has a curative effect on cigarette-induced injuries on the skin tissues by anti-oxidative and anti-inflammatory effects.
Keywords: Alpha lipoic acid; cigarette smoking; reactive oxygen species; skin damage.