Lung protective effect of Apigenin against X-ray radiation: an experimental study

Abstract The lung is a radiation-sensitive organ. When cells are damaged due to accidental radiation exposure or treatment, they release molecules that lead to the recruitment of immune cells, resulting in the accumulation of inflammatory cytokines at the site of damage. Apigenin (Api) is a natural flavonoid known for its anti-inflammatory properties. In this study, we investigated the radioprotective properties of Api in the lung. Materials and methods: Thirty-six Wistar rats were randomly assigned to nine groups: control, radiation (Rad), CMC + Rad, Rad + Api 10, and Rad + Api 20. Api was administered with an intraperitoneal injection for 7 days, after which the rats were irradiated with 6 Gy whole-body X-rays. At 6 and 72 hours post-irradiation, the rats were euthanized, and their lung tissue was extracted. Results: Radiation led to increased alveolar wall thickness and the infiltration of macrophages and lymphocytes. Furthermore, the expression levels of inflammatory factors such as nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-ĸB), Glycogen synthase kinase-3 beta (GSK-3β), transforming growth factor-beta1 (TGF-β1), and epigenetic factors including DNA methyltransferase 3a (DNMT3a) and Histone deacetylase 2 (HDAC2) were elevated in the lung tissue following radiation. Meanwhile, the expression level of IκBα decreased. However, administration of Api (at both 10 and 20 doses) reversed the adverse effects induced by radiation. ​Conclusion: In conclusion, Api administration mitigated radiation-induced lung damage by reversing inflammatory and epigenetic changes.