title: Protective effect of β-casomorphin-7 on cardiomyopathy of streptozotocin-induced diabetic rats via inhibition of hyperglycemia and oxidative stress.
abstract: β-Casomorphin-7 (β-CM-7) is regarded as the most representative milk-derived bioactive peptide. The present work studies the efficacy of β-CM-7 against myocardial injury in streptozotocin-induced diabetic rats, focusing on the following assays: (1) the level of blood glucose and advanced glycosylation end product (AGE), the activity of lactate dehydrogenase (LDH) in serum; (2) the level of hydrogen peroxide (H2O2), the activity of Na(+)K(+)-ATPase, Ca(2+)Mg(2+)-ATPase and enzymatic antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) in myocardial tissue; (3) the protein expression of glucose transporter-4 (GLUT-4) in myocardial tissue. It showed that with the influence of β-CM-7, the levels of blood glucose of β-CM-7 treatment group decreased markedly compared with model group (P<0.01) accompanied with their alleviated symptoms of diabetes. In the antioxidant and oxidant levels, β-CM-7 treatment group signified a remarkable increase in the activity of GSH-Px, SOD and CAT of the anti-oxidation system and meanwhile demonstrated a considerable reduction in H2O2 content (all P<0.05) in comparison with model group. We also found both the content of AGE and the activity of LDH of β-CM-7 treated group considerably reduced while the content of GLUT-4 and the activity of Na(+)K(+)-ATPase and Ca(2+)Mg(2+)-ATPase of β-CM-7 treated group increased obviously (P<0.05). Meanwhile the cardiac indexes were significantly lessened. Thus our assay validates that the remedy employing β-CM-7 may treat diabetic cardiomyopathy with high efficacy predominantly associated with the mechanism that β-CM-7 ameliorates myocardial energy metabolism and abates free-radical-mediated oxidative stress in blood and myocardium.
authors.affiliation: Key Laboratory of Animal Physiology and Biochemistry, Nanjing Agricultural University, Nanjing 210095, People's Republic of China.
authors.forename: Dong-Ning
authors.initials: DN
authors.lastname: Han
authors.forename: Dong-Hui
authors.initials: DH
authors.lastname: Zhang
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Wang
authors.forename: Yuan-Shu
authors.initials: YS
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001786:Blood Glucose; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D058065:Diabetic Cardiomyopathies / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D004353:Drug Evaluation, Preclinical; D004723:Endorphins / Q000627:therapeutic use*; D051275:Glucose Transporter Type 4 / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D017127:Glycation End Products, Advanced / Q000097:blood; D006861:Hydrogen Peroxide / Q000378:metabolism; D006943:Hyperglycemia / Q000097:blood / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000627:therapeutic use*; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010446:Peptide Fragments / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013311:Streptozocin; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D004723:Endorphins; D051275:Glucose Transporter Type 4; D017127:Glycation End Products, Advanced; D007004:Hypoglycemic Agents; D010446:Peptide Fragments; C495694:Slc2a4 protein, rat; D013311:Streptozocin; C041128:beta-casomorphin 7; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D017301:Ca(2+) Mg(2+)-ATPase; D000254:Sodium-Potassium-Exchanging ATPase