Evaluation of the Mitigation Effect of Spirulina Against Lung Injury Induced by Radiation in Rats

Some compounds have been investigated to mitigate the effect of radiation on the lung, such as pneumonitis and fibrosis.

This study aimed to examine the mitigation efficiency of Spirulina compared to the effect of Metformin.

25 male Wistar rats were allotted in five groups: control, Spirulina, Radiation, Radiation plus Spirulina, and Radiation plus Metformin. Rat chest regions were irradiated by 15 Gray (Gy) xradiation using aLINAC. Forty-eight hours after irradiation, treatment with Spirulina and Metformin began. Eighty days after irradiation, all rats were sacrificed, and their lung tissues were removed for histopathological, and biochemical assays.

The results demonstrated that irradiation increased MDA (Malondialdehyde) levels while suppressing the SOD (superoxide dismutase) and GPx(glutathione peroxidase) activity in the irradiated group. MDA levels in lung tissues were reduced with Metformin but not with Spirulina. Both Metformin and Spirulina increased the SOD and GPx activity in lung tissue. Moreover, histopathological evaluations showed extensive changes in the lung tissue including infiltration of lymph cells around the bronchioles and blood vessels, thickening of the alveolar wall, and the disruption of the alveolar structure, as well as accumulation of collagen fibers. Administration of Spirulina and Metformin significantly reduced pathological changes in lung tissue, although the effect of Metformin was greater than that of Spirulina.

Spirulina could mitigate radiation-induced lung injury moderately, although Metformin is more effective than Spirulina as a mitigator agent.