Polymerized human placenta hemoglobin (PolyPHb) attenuates myocardial infarction injury in rats.

Objectives: To investigate the cardioprotective effect of polymerized human placenta hemoglobin (PolyPHb) for acute myocardial ischemia rat heart.

Methods: Myocardial infarcts (MI) model was set up in SD rats by permanent ligation of the left anterior descending coronary artery (LDA). The rats were divided randomly into 3 groups with each group of 20 rats: (A) the control group with the administration of Ringer's lactated solution at a dose of 2.5ml/kg); (B) PolyPHb group, PolyPHb solution at a dose of 0.16g Hb/kg and (C), PolyPHb+CAT+SOD group, PolyPHb solution at a dose of 0.16g Hb/kg and catalase (CAT) solution and superoxide dismutase (SOD) solution at a dose of 1681 U/kg and 528000 U/kg, respectively. Each rat received treatments via caudal vein, once a day for 7 days. Qualitative evaluations were made based on the reading of cardiac troponin T (cTnT), the myocardial infarction size (MIS) derived from the staining of myocardium tissue, and the pathological changes in infarct area. The ischemia changes of cardiomyocytes were determined by haematoxylin - basic fuchsin - picric acid (HBFP) staining and the apoptosis of cardiomyocytes were evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay (TUNEL).

Results: Compared to the control group, PolyPHb greatly decreased the cTnT (p < 0.05), MIS (p < 0.05), and the size of myocardial ischemia (p < 0.05). PolyPHb + CAT + SOD decreased the △ST change (P < 0.05), cTnT (P < 0.01), MIS (p < 0.05), the pathological scores (p < 0.01), the size of myocardial ischemia (p < 0.01), and the apoptosis level (p < 0.01).

Conclusion: Our study demonstrated that adding PolyPHb improves cardiac functional recovery and reduces myocardial infarction of rat heart.