[Effect of erythropoietin on apoptosis following hyperoxic lung injury in neonatal rats].
OBJECTIVE
To study the effect of recombinant human erythropoietin (rhEPO) on apoptosis following hyperoxic lung injury in neonatal rats.


METHODS
Ninety-six neonatal Sprague-Dawley rats were randomly divided into four groups: air-exposed control, air-exposed rhEPO-treated, hyperoxia-exposed placebo (95% oxygen), and hyperoxia-exposed rhEPO-treated. rhEPO (800 U/kg) was administered 2, 4, and 6 days after air or hyperoxia exposure. The rats were sacrificed 3, 7 and 14 days after air or hyperoxia exposure for the assessment of lung histological changes by hematoxylin and eosin staining (n=8 each time point). p-JNK levels were measured by Western blot. Lung cell apoptosis was evaluated by TUNEL assay.


RESULTS
Compared with the air-exposed control group, inflammatory cell infiltration was found at 3 days and increased obviously at 7 days, and widening of the alveolar septa was observed, the number of alveoli decreased and normal alveolarization disappeared at 14 days after hyperoxia exposure in the hyperoxia-exposed placebo group. rhEPO treatment alleviated significantly the hyeroxia-induced alterations in lung pathology. P-JNK protein levels and the number of apoptosis cells decreased significantly in the hyperoxia-exposed rhEPO-treated compared with those in the hyperoxia-exposed placebo group.


CONCLUSIONS
rhEPO may reduce apoptosis and thus provide a protective effect against hyperoxic lung injury in neonatal rats. JNK signal pathway may be involved in the protective mechanism.
Ding
Lu
L
Department of Neonatology, Shenzhen People's Hospital, Shenzhen, Guangdong 518020, China.
Wu
Ben-Qing
BQ
Huang
Jin-Jie
JJ
Liu
Zhi-Ping
ZP
Chen
Li
L
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects*; D001997:Bronchopulmonary Dysplasia / Q000188:drug therapy; D004921:Erythropoietin / Q000494:pharmacology*; D005260:Female; D006801:Humans; D018496:Hyperoxia / Q000473:pathology*; D007231:Infant, Newborn; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008168:Lung / Q000473:pathology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins
D011994:Recombinant Proteins; D004921:Erythropoietin; D048031:JNK Mitogen-Activated Protein Kinases