Ameliorative Effects of Sunflower Seeds Powder on High Fat Diet Induced Metabolic Changes in Wistar Rats

Abstract

Background: Obesity and prediabetes are reversible disorders affecting people globally with no sex predilection. They can progress to diabetes mellitus with resultant complications. Studies have shown greater involvement of high fat diets in the etiology of obesity and prediabetic conditions. Sunflower (Helianthus Anuus) extracts with an LD50> 5000mg/kg has been found to be effective in reducing high blood sugar levels in both human and animal studies. Sunflower seed powder was used in this study to investigate its effects on high fat diet (HFD) induced metabolic changes in Wistar rats.
Methods: A total of 27 male Wistar rats (350 - 400 grams) were used for this study. They were  randomly assigned to 9 groups of 3animals each and were fed for 6 weeks. Group 1 served as control (water and feed ad libitum) Group 2 (high fat diet alone); Group 3 (HFD + 5000mg/kg of sunflower seed concurrently); Group 4 (HFD + 3000mg/kg of sunflower seed concurrently); Group 5 (high fat diet + 2000mg/kg of sunflower seed concurrently ); Group 6 (HFD for 5 weeks + 5000mg/kg of sunflower seed for 1week); Group 7 (HFD for 5weeks + 3000mg/kg of sunflower seed for 1wk); Group 8 (HFD for 5 wks + 2000 mg of sunflower seed for 1wk); Group 9 (HFD for 5 wks + 70mg/kg Metformin for 1 week). Animals were anesthetized with ketamine and blood collected via cardiac puncture. Blood glucose measurement was done using the glucose oxidase method and plasma insulin levels were measured using ultra sensitive rats Insulin ELISA kit marketed by Crystal chem, specificity 100% and sensitivity, 0.05 ng/ml, serum glycated albumin and haemoglobin was measured using the Variant TMIIT urbohigh-performance liquid chromatography system. Harvested pancreatic tissues were fixed in 10%
formalin for histomorphological analyses.
Results: Blood glucose, plasma glycated haemoglobin in the HFD only group were significantly higher (p<0.05) compared to control and other groups. The sunflower treated groups with 5000mg, 3000mg and 2000mghad significantly decreased (p<0.05) insulin levels compared to control group and similar to metformin and HFD alone groups. Pancreatic histology results showed that HFD caused significant destruction of islet cells which was preserved in the sunflower co-administered groups.
Conclusions: Sunflower seed significantly reduce blood sugar level, reduced HbA1c, and conferred cyto-protection on islets of Langerhan cells.