Gene expression profiling in non-human primate jejunum, ileum and colon after total-body irradiation: a comparative study of segment-specific molecular and cellular responses

BMC Genomics

Research Article

Mylene Pouliot¹  Simon Authier¹  Junying Zheng²  Daohong Zhou²  Junru Wang²  Martin Hauer-Jensen³  David S. Loose⁴ 

[1] CiToxLAB North America, H7V 4B3, Laval, Quebec, Canada;Division of Radiation Health, University of Arkansas for Medical Sciences, 72205, Little Rock, Arkansas, USA;Division of Radiation Health, University of Arkansas for Medical Sciences, 72205, Little Rock, Arkansas, USA;Surgical Service, Central Arkansas Veterans Healthcare System, 72205, Little Rock, Arkansas, USA;Integrative Biology and Pharmacology, University of Texas Medical School at Houston, 77030, Houston, TX, USA;

关键词: Total body irradiation;    Tumor necrosis factor α;    Gastrointestinal injury;   

DOI  :  10.1186/s12864-015-2168-y

 received in 2015-05-14, accepted in 2015-10-29,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundAlthough extensive studies have investigated radiation-induced injuries in particular gastrointestinal (GI) segments, a systematic comparison among the different segments on the basis of mode, magnitude and mechanism has not been reported. Here, a comparative study of segment-specific molecular and cellular responses was performed on jejunum, ileum and colon obtained at three time points (4, 7 and 12 days after irradiation) from non-human primate (Rhesus macaque) models exposed to 6.7 Gy or 7.4 Gy total body irradiation (TBI).ResultsPathway analysis on the gene expression profiles identified radiation-induced time-, dose- and segment-dependent activation of tumor necrosis factor α (TNFα) cascade, tight junction, apoptosis, cell cycle control/DNA damage repair and coagulation system signaling. Activation of these signaling pathways suggests that colon sustained the severest mucosal barrier disruption and inflammation, and jejunum the greatest DNA damage, apoptosis and endothelial dysfunction. These more pronounced alterations correlate with the high incidence of macroscopic pathologies that are observed in the colon after TBI. Compared to colon and jejunum, ileum was resistant to radiation injury. In addition to the identification a marked increase of TNFα cascade, this study also identified radiation induced strikingly up-regulated tight junction gene CLDN2 (196-fold after 7.4-Gy TBI), matrix degradation genes such as MMP7 (increased 11- and 41-fold after 6.7-Gy and 7.4-Gy TBI), and anoikis mediated gene EDA2R that mediate mucosal shedding and barrier disruption.ConclusionsThis is the first systematic comparative study of the molecular and cellular responses to radiation injury in jejunum, ileum and colon. The strongest activation of TNFα cascades and the striking up-regulation of its down-stream matrix-dissociated genes suggest that TNFα modulation could be a target for mitigating radiation-induced mucosal barrier disruption.

【 授权许可】

CC BY   
© Zheng et al. 2015