[Effect of heat shock protein 70 on nuclear factor-KappaB/inhibitor protein-alpha of nuclear factor-KappaB in brain edema induced by infection in rat].
OBJECTIVE
To study the effect of heat shock protein 70 (HSP70) on activation of nuclear factor-KappaB (NF-KappaB) and degradation of inhibitor KappaB-alpha protein (I-Kappa B alpha) in brain edema induced by Pertussis bacilli infection in rats.


METHODS
Brain edema was induced by injection of Pertussis bacilli suspension via the left internal carotid artery. Seventy-two Sprague-Dawley rats were divided randomly into brain edema group, pretreatment with heat shock group, and normal saline control group. The rats were sacrificed 4, 8 and 24 hours after injection of Pertussis bacilli and normal saline, respectively. HSP70 expression and the degradation of I-Kappa B alpha were assayed in all animals with Western blot analysis. Electrophoretic mobility shift assay (EMSA) was performed to assess NF-KappaB activation of nuclear extract of neurones.


RESULTS
The results showed that HSP70 expression was significantly increased in heat shock group compared with control group and brain edema group. The activity of NF-KappaB started to increase at 2 hours in brain edema group and peaked at 24 hours. The expression of I-Kappa B alpha began to decrease at 2 hours and reached the lowest level at 24 hours. In heat shock group the activity of NF-KappaB complexes was lower than that in brain edema group, and the expression of I-Kappa B alpha higher than that in brain edema group at corresponding time points.


CONCLUSIONS
HSP70 shows a protective effect on development of brain edema as its expression increases. The mechanism might be associated with its inhibitory effect on degradation of I-Kappa B alpha and activation of NF-KappaB.
Mao
Ding-an
DA
Department of Pediatrics, The Second Xiangya Hospital, Central South University, Changsha 410011, Hunan, China.
Yang
Yu-Jia
YJ
Yu
Yan
Y
D000818:Animals; D001921:Brain / Q000378:metabolism; D001929:Brain Edema / Q000378:metabolism*; D004195:Disease Models, Animal; D005260:Female; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D020672:I-kappa B Proteins / Q000378:metabolism*; D008297:Male; D016328:NF-kappa B / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014917:Whooping Cough / Q000378:metabolism* / Q000473:pathology
D018840:HSP70 Heat-Shock Proteins; D020672:I-kappa B Proteins; D016328:NF-kappa B