Effects of erythropoietin on cardiomyocyte apoptosis and endoplasmic reticulum stress-related proteins in neonatal rats with asphyxia.
- Author:
Li-Jia WAN
1
;
Xing-Heng WU
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Animals, Newborn; Apoptosis; drug effects; Asphyxia Neonatorum; drug therapy; pathology; Creatine Kinase; blood; Endoplasmic Reticulum Stress; physiology; Erythropoietin; pharmacology; Heat-Shock Proteins; analysis; L-Lactate Dehydrogenase; blood; Myocytes, Cardiac; drug effects; pathology; Rats; Rats, Sprague-Dawley; Transcription Factor CHOP; analysis
- From: Chinese Journal of Contemporary Pediatrics 2013;15(10):890-895
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo study the effects of erythropoietin (EPO) on cardiomyocyte apoptosis and endoplasmic reticulum stress (ERS)-related proteins, glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP), in neonatal rats with asphyxia.
METHODSA total of 120 newborn Sprague-Dawley rats (7 days old) were randomly divided into sham-operated (n=40), asphyxia (n=40) and EPO-treated asphyxia groups (n=40). A neonatal rat model of normobaric asphyxia was established in the asphyxia and EPO-treated asphyxia groups. The rats in the EPO-treated asphyxia group received intraperitoneal injection of recombinant human erythropoietin (500 U/mL) immediately after the model was established, while the other two groups received the same volume of normal saline (0.9%). Heart blood and myocardial tissue samples were collected from 8 rats in each group at 2, 6, 12, 24 or 48 hours after the model was established. Serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels were measured; cardiomyocyte apoptosis was evaluated, and expression of myocardial GRP78 and CHOP was measured.
RESULTSCompared with the sham-operated and EPO-treated asphyxia groups, the asphyxia group had significantly increased serum CK and LDH levels, number of apoptotic cells, and expression of myocardial GRP78 and CHOP at each time point (P<0.01), and all the indices were significantly higher in the EPO-treated asphyxia group than in the sham-operated group (P<0.01). At 24 hours after asphyxia, the expression of myocardial CHOP was positively correlated with the myocardial apoptosis index (r=0.944, P<0.01).
CONCLUSIONSEPO exerts a protective effect on the myocardium of neonatal rats with hypoxic-ischemic injury by regulating ERS-related proteins GRP78 and CHOP and reducing cardiomyocyte apoptosis.