Radiation-induced lung injury is a common complication of radiotherapy for lung cancer, breast cancer, esophageal cancer, and thymoma. This study aims to illustrate biomarkers of radiation-induced lung injury and its potential mechanism through the study of metabolomic alterations in serum of Sprague-Dawley rats with different radiation doses. Serum from 0, 10, or 20 Gy irradiated rats were collected and subjected to gas chromatography-mass spectrometry. The result showed that there were 23 dysregulated metabolites between the 10 Gy irradiation group and the 0 Gy control group, whereas 36 preferential metabolites were found between the 20 Gy irradiated rat serum and the control groups. Among them, there were 19 common differential metabolites in the 2 irradiation groups, including 3 downregulated (benzyl thiocyanate, carbazole, and N-formyl-L-methionine) and 16 upregulated metabolites. We further analyzed the metabolic pathways of different metabolites; the results showed that there were 3 significant enrichment pathways in the 10 Gy vs 0 Gy group and 7 significant enrichment pathways in the 20 Gy vs 0 Gy group. Among them, taurine and hypotaurine metabolism, riboflavin metabolism, and glyoxylate and dicarboxylate metabolism were the common metabolic enrichment pathways of the 10 Gy vs 0 Gy group and the 20 Gy vs 0 Gy group.

1. Li, X, Zhuang, X, Qiao, T. Role of ferroptosis in the process of acute radiation-induced lung injury in mice. Biochem Biophys Res Commun. 2019;519(2):240-245.
Google Scholar | Crossref | Medline2. Cui, L, Zheng, D, Lee, YH, et al. Metabolomics investigation reveals metabolite mediators associated with acute lung injury and repair in a murine model of influenza pneumonia. Sci Rep. 2016;6:26076.
Google Scholar | Crossref | Medline3. Jones, JW, Jackson, IL, Vujaskovic, Z, Kaytor, MD, Kane, MA. Targeted metabolomics identifies pharmacodynamic biomarkers for BIO 300 mitigation of radiation-induced lung injury. Pharm Res (N Y). 2017;34(12):2698-2709.
Google Scholar | Crossref | Medline4. Gao, Y, Li, X, Gao, J, et al. Metabolomic analysis of radiation-induced lung injury in rats: The potential radioprotective role of taurine. Dose Response. 2019;17(4):1-11.
Google Scholar | SAGE Journals5. Amini, A, Yeh, N, Gaspar, LE, Kavanagh, B, Karam, SD. Stereotactic body radiation therapy (SBRT) for lung cancer patients previously treated with conventional radiotherapy: A review. Radiat Oncol. 2014;9:210.
Google Scholar | Crossref | Medline | ISI6. Yamashita, T, Kato, T, Isogai, T, Gu, Y, Ma, N. Protective effects of taurine on the radiation exposure induced cellular damages in the mouse intestine. Adv Exp Med Biol. 2019;1155:443-450.
Google Scholar | Crossref | Medline7. Ma, N, Kato, T, Isogai, T, Gu, Y, Yamashita, T. The potential effects of taurine in mitigation of radiation nephropathy. Adv Exp Med Biol. 2019;1155:497-505.
Google Scholar | Crossref | Medline8. Mousavi, K, Niknahad, H, Ghalamfarsa, A, et al. Taurine mitigates cirrhosis-associated heart injury through mitochondrial-dependent and antioxidative mechanisms. Clin Exp Hepatol. 2020;6(3):207-219.
Google Scholar | Crossref | Medline