All issues > Volume 45(9); 2002

Original Article

J Korean Pediatr Soc. 2002;45(9):1106-1113. Published online September 15, 2002.

iption Factor NF-κB Caused by Acute Hypoxia in the Heart

Chan Uhng CU Joo¹, Woo Suk WS Juhng¹, Jae Cheol JC Kim¹, Ho Keun HK Yi¹

¹Department of Pediatrics, Institute of Cardiovascular Research, Medical School, Chonbuk National University, Jeonju, Korea

Correspondence Chan Uhng CU Joo ,Email: joocu@moak.chonbuk.ac.kr

Abstract

Purpose
: Nuclear factor-κB(NF-κB) is now recognized as playing a potential role in programmed cell death and the adaptive response to various stress. Cellular hypoxia is a primary manifestation of many cardiovascular diseases. It seems that vascular endothelial growth factor (VEGF) and insulin like growth factor-I(IGF-I) have a function as a protective molecule in the heart against several stress including hypoxia. In this study, the role of NF-κB to the cellular response and regulation of protective molecules against the acute hypoxia in the heart was studied.
Methods
: To cause acute hypoxic stress to the heart, Sprague Dawley rats were exposed to hypoxic chamer(N2 92% and O2 8%). After the hypoxic exposure, nuclear proteins, total proteins and mRNA were isolated from heart. Translocation of the transcription factors NF-κB, NF-ATc, AP-1 and NKX-2.5 were evaluated by electrophoretic mobility shift assay(EMSA). The expression of IGF-I and VEGF were studied before and after the hypoxic stress by competitive-PCR, Northern hybridization and Western hybridization. To confirm the role of the NF-κB in the heart, the rats also were pretreated with diethyl-dithiocarbamic acid(DDTC) into peritoneal cavity to block NF-κB translocation into nucleus.
Results
: The expression of NF-κB, AP-1 and NF-ATc were increased by the hypoxic stress. Increased expression of the VEGF and IGF-I were also observed by the hypoxic stress. However, the blocking of the NF-κB translocation reduced those expressions of VEGF and IGF-I.
Conclusion
: These results suggest that NF-κB has a protective role against the acute hypoxia through several gene expression, especially VEGF and IGF-I in heart muscle.

Keywords :NF-Κb, Hypoxia, VEGF, IGF-I