Hibiscus sabdariffa(Roselle) Polyphenol-rich Extract Averts Cardiac Functional and Structural Abnormalities in Type 1 Diabetic Rats.
Appl Physiol Nutr Metab. 2018 May 4. Epub 2018 May 4. PMID: 29726706
Nur Liyana Mohammed Yusof
Diabetes mellitus is often associated with cardiac functional and structural alteration, an initial event leading to cardiovascular complications.Hibiscus sabdariffaor roselle has been widely proven as an antioxidant and recently has incited research interest for its potential in treating cardiovascular disease. Therefore, this study aimed to determine the cardioprotective effects ofH. sabdariffa(roselle) polyphenol-rich extract (HPE) in type-1 induced diabetic rats. Twenty-four male Sprague-Dawley rats were randomized into four groups (n=6/group): non-diabetic (NDM), diabetic alone (DM), diabetic supplemented with HPE (DM+HPE) and metformin (DM+MET). Type-1 diabetes was induced with streptozotocin (55 mg/kg/i.p). Rats were forced-fed HPE (100 mg/kg) and metformin (150 mg/kg) daily for eight weeks. Results showed that HPE supplementation improved hyperglycemia and dyslipidemia significantly (p<0.05) in DM+HPE compared to DM group. HPE supplementation attenuated cardiac oxidative damage in DM group, indicated by low malondialdehyde and advanced oxidation protein product. As for the antioxidant status, HPE significantly (p<0.05) increased glutathione level, as well as catalase and superoxide dismutase 1 and 2 activities. These findings correlate with cardiac function, whereby HPE supplementation improved left ventricle developed pressure, coronary flow, cardiac contractility and relaxation rate significantly (p<0.05). Histological analysis showed a marked decrease in cardiomyocyte hypertrophy and fibrosis in DM+HPE compared to DM group. Ultrastructural changes and impairment of mitochondria induced by diabetes were minimized by HPE supplementation. Collectively, these findings suggest that HPE is a potential cardioprotective agent in a diabetic setting through its hypoglycemic, anti-hyperlipidemia and antioxidant properties.