Inhibitory effects of Nigella sativa nano-capsule on the expression of cyclin D1 in the lungs of wistar rats exposed to nicotine-derived nitrosamine ketone

Background: Researchers argue that supplements are somewhat capable of influencing the lung tissue exposed to smoking carcinogens through cell cycle. Cyclin D1 is a gene involved in cell cycle. Objective: This study aimed to investigate the effects of 12-week injection of Nigella sativa nano-capsule on the expression of Cyclin D1 of the lung tissue of the rats receiving exposure to Nicotine-Derived Nitrosamine Ketone. Method: 46 Wistar rats were assigned into five groups: NNK, Supplement, and Supplement, + NNK, Control and Vehicle group. 125 μg/kg body weight of Nigella sativa nano-capsule supplement was injected subcutaneously into the Supplement and Supplement NNK groups once a week. NKK and Vehicle groups received a weekly dose of 12.5 mg/kg NNK and distilled water for 12 weeks through subcutaneous injection. After isolating the lung tissue, the expression of the Cyclin D1 gene was measured using Real Time PCR-ABI. One-way ANOVA parametric analysis and Tukey post hoc test were used to analyze the data at the significant level of P ≤ 0.05. Results: According to the results, the expression of Cyclin 1 gene was relatively reduced in Supplement NNK (P = 0.003) and Vehicle (P = 0.001) groups in comparison to the NNK group. Nevertheless, no significant difference was observed among the Supplement, Vehicle, and Control groups. We believe that Nigella sativa nano-capsule supplement reduced the relative changes of Cyclin 1 in the lung tissues exposed to carcinogen NNK. Conclusion: Apparently, this supplement is capable of reducing Cyclin 1 level in cell cycle; hence, it can reduce the carcinogenic effects of NNK and the negative effects of smoking among other therapeutic methods.