Z Gastroenterol 2008; 46 - P1_43
DOI: 10.1055/s-2008-1037499

Effect of X-irradiation on gene expression of rat liver chemokines: in vivo and in vitro studies

F Moriconi 1, H Christiansen 2, H Christiansen 3, N Sheikh 2, J Dudas 2, RM Hermann 3, RM Hermann 2, M Rave-Fränk 2, D Raddatz 2, B Saile 2, CF Hess 4, CF Hess 3, G Ramadori 2
  • 1Abteilung Gastroenterologie und Endokrinologie, Göttingen
  • 2Abteilung für Gastroenterologie und Endokrinologie, Göttingen
  • 3Abteilung Strahlentherapie und Radioonkologie, Georg-August-Universität, Göttingen
  • 4Abteilung Strahlentherapie und Radioonkologie, Universitätsklinikum Göttingen, Göttingen

PURPOSE: The liver is considered to be a radiosensitive organ. In fact, irradiation may lead to cirrhosis development. However inflammation was not observed in the rat liver after X-irradiation. As chemokine production is necessary for the recruitment of inflammatory cells in case of inflammation, aim of the study was to analyze the effect of X-irradiation on chemokine-gene-expression in rat liver and in isolated rat hepatocytes.

METHODS AND MATERIALS: Rat livers and isolated rat hepatocytes were X-irradiated. RNA extracted from livers and from hepatocytes within the first 48 hours after irradiation was analyzed by real time PCR- and Northern Blot-techniques. Chemokine concentration in serum of irradiated rats was quantitatively measured by ELISA. Sham-irradiated animals served as controls in all experiments.

RESULTS: A significant radiation-induced increase of CINC–1-, IP–10-, MCP–1-, MIP–3α-, MIP–3β-, MIG-, and ITAC-gene-expression could be detected within the first 48 hours after irradiation on the RNA level in the liver. In addition, CINC–1, MCP–1, and IP–10 serum levels were significantly increased. In rat hepatocytes in vitro only MIP–3α showed a radiation-induced increased expression and CINC–1, IP–10, MIP–3β, MIG, MIP–1α, ITAC and SDF–1 RNA levels were significantly down-regulated. However, incubation of irradiated hepatocytes in vitro with either TNF-α, IL–1β, or IL–6 and TNF-α led to an up-regulation of MCP–1, IP–10 and MCP–1, or CINC–1 and MIP–3β, respectively.

CONCLUSION: X-irradiation of the liver is able to induce up-regulation of the genes of the main proinflammatory chemokines probably through the induction of proinflammatory cytokines. The reason for the lack of liver inflammation in this model has still to be clarified.

Chemokines - Liver - X-irradiation