title: Molecular responses of radiation-induced liver damage in rats.
abstract: The aim of the present study was to investigate the molecular responses involved in radiation‑induced liver damage (RILD). Sprague‑Dawley rats (6‑weeks‑old) were irradiated once at a dose of 20 Gy to the right upper quadrant of the abdomen. The rats were then sacrificed 3 days and 1, 2, 4, 8 and 12 weeks after irradiation and rats, which were not exposed to irradiation were used as controls. Weight measurements and blood was obtained from the rats and liver tissues were collected for histological and apoptotic analysis. Immunohistochemistry, reverse transcription quantitative polymerase chain reaction (RT‑qPCR) and western blot analysis were performed to measure the expression levels of mRNAs and proteins, respectively. The serum levels of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase were increased significantly in the RILD rats. Histological investigation revealed the proliferation of collagen and the formation of fibrotic tissue 12 weeks after irradiation. Apoptotic cells were observed predominantly 2 and 4 weeks after irradiation. The immunohistochemistry, RT‑qPCR and western blot analysis all revealed the same pattern of changes in the expression levels of the molecules assessed. The expression levels of transforming growth factor‑β1 (TGF‑β1), nuclear factor (NF)‑κB65, mothers against decapentaplegic homolog 3 (Smad3) and Smad7 and connective tissue growth factor were increased during the recovery period following irradiation up to 12 weeks. The expression levels of tumor necrosis factor‑α, Smad7 and Smad4 were only increased during the early phase (first 4 weeks) of recovery following irradiation. In the RILD rat model, the molecular responses indicated that the TGF‑β1/Smads and NF‑κB65 signaling pathways are involved in the mechanism of RILD recovery.
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Aimudula
authors.initials: A
authors.lastname: Ainiwaer
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Yunlian
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Ge
authors.initials: G
authors.lastname: Wu
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Mao
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China.
authors.forename: Yongxing
authors.initials: Y
authors.lastname: Bao
mesh_terms: D000818:Animals; D001835:Body Weight / Q000528:radiation effects; D004195:Disease Models, Animal; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D008099:Liver / Q000378:metabolism* / Q000473:pathology / Q000528:radiation effects*; D008103:Liver Cirrhosis / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D008111:Liver Function Tests; D008297:Male; D011833:Radiation Injuries, Experimental / Q000097:blood / Q000235:genetics*; D051381:Rats