A possible cardioprotective effect of heat shock proteins during cardiac surgery in pediatric patients.
BACKGROUND
Overexpression of heat shock proteins (Hsps) is associated to myocardial protection and it has been suggested that they could be a marker of cardiac preservation in conditions such as extracorporeal circulation. Aim of this study was to evaluate if cardioplegic arrest can modify the expression of Hsps in the heart and if this alteration is associated to cardiac preservation.


METHODS
The levels of Hsp 27, Hsp 60, and both the constitutive and the inducible form of Hsp 70 were measured in the cardiac tissue from right atrium of pediatric patients before and after aortic cross-clamping (ACC) during cardiopulmonary bypass surgery for correction of congenital heart disease (n=20). The quantitative evaluation of Hsps was made by Western blotting analysis after tissue extraction and protein separation. Hsp 72 mRNA expression was also evaluated in pre- and post-ACC samples of eight subjects by semiquantitative RT-PCR. Peripheral levels of Troponin I, Myoglobin, LDH, CK, CK-MB were measured in basal conditions and at 12 and 24h after cardiosurgery as markers of heart damage.


RESULTS
The cardioplegic arrest did not significantly modify the mean levels of all the Hsps measured. Hsp 72 levels increased after cardioplegia in the 40% of the patients and all Hsps in the 28% of subjects. The patients whose levels of Hsps are increased after cardioplegia are associated with lower post-surgery concentrations of all the markers of cardiac injury.


CONCLUSIONS
This observation suggests a relationship between the increase of Hsps and the reduction of cardiac injury.
Giannessi
Daniela
D
Laboratory of Cardiovascular Biochemistry, CNR Institute of Clinical Physiology, Via Moruzzi, 156100 Pisa and G. Pasquinucci Hospital, Massa, Italy. danielag@ifc.pi.cnr.it
Caselli
Chiara
C
Vitale
Rosa Letizia
RL
Crucean
Adrian
A
Murzi
Bruno
B
Del Ry
Silvia
S
Vanini
Vittorio
V
Biagini
Andrea
A
D015415:Biomarkers; D015153:Blotting, Western; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002314:Cardioplegic Solutions; D002648:Child; D002675:Child, Preschool; D003250:Constriction; D003402:Creatine Kinase / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006324:Heart Arrest, Induced; D006331:Heart Diseases / Q000209:etiology* / Q000503:physiopathology; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000502:physiology*; D006801:Humans; D007223:Infant; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D009211:Myoglobin / Q000378:metabolism; D012313:RNA / Q000096:biosynthesis / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019210:Troponin I / Q000378:metabolism
D015415:Biomarkers; D002314:Cardioplegic Solutions; D006360:Heat-Shock Proteins; D009211:Myoglobin; D019210:Troponin I; D012313:RNA; D007770:L-Lactate Dehydrogenase; D003402:Creatine Kinase