Effects of Dietary Onion (<i>Allium cepa</i> L.) in a High-Fat Diet Streptozotocin-Induced Diabetes Rodent Model

Abstract

Background/Aims: The present study was conducted to investigate the effects of two dietary doses of freeze-dried onion powder on diabetes-related symptoms in a high-fat (HF) diet streptozotocin (STZ)-induced diabetes rat model. Methods: Five-week-old male Sprague-Dawley rats were fed a HF diet for 2 weeks and then randomly divided into 4 groups as follows: HF control (HFC), diabetic control (DBC), onion low (ONL; 0.5%) and onion high (ONH; 2.0%). Diabetes was induced by an intraperitoneal injection of STZ (40 mg/kg body weight) in all groups except the HFC group. Results: After 4 weeks on the experimental diets, fasting blood glucose levels for both onion-fed groups were higher than in the DBC and HFC groups, albeit only significantly so (p < 0.05) in the ONL group. Serum insulin concentrations and insulin resistance were dose-dependently increased (however, not significantly so) in the onion-fed groups compared to the DBC group. Pancreatic β-cell function and liver glycogen concentrations were nonsignificantly higher in the DBC and ONH groups compared to the ONL group. Additionally, the ONH group had significantly higher lipid concentrations (except for high-density lipoprotein cholesterol) compared to all other groups. The ONL group showed a similar hyperlipidemic trend, however to a lesser extent, with only triglycerides significantly differing from those of the DBC and HFC groups. Conclusion: The results suggest that the HF onion diet may increase insulin secretion and consequently insulin resistance in a dose-dependent manner, resulting in a worsened hyperglycemic and hyperlipidemic diabetic state. We conclude that higher dietary fat may impair the antidiabetic effects of dietary onion intake as has been previously reported.

Biochemical characterization and 1H NMR based metabolomics revealed Melicope lunu-ankenda leaf extract a potent anti-diabetic agent in rats

“…HFD usually results in obesity leading to insulin resistance, whereas low dose of STZ causes moderate destruction of insulin secretion [23]. …”

Testosterone in Males as Enhanced by Onion (Allium Cepa L.)

“…Accordingly, the energy value of onion is not significant (~40 kcal/100 g) [13]. Most importantly, onions were found to contain several and unique phytochemicals such as quercetin and quercetin glucosides, kaempferol, thiosulfinates, cepaenes, anthocyanins, and sulfur compounds (e.g., S-methyl cysteine sulfoxide, diallyl trisulfide, S-allyl cysteine sulfoxide, dimethyl trisulfide) that have been identified to have an impact on humans’ health [14,15]. Yet, some of these phytochemicals are under basic and translational research to explore their possible biological effects in humans.…”

Protective effects of onion-derived quercetin on glutamate-mediated hippocampal neuronal cell death

“…[12] Recently, it was shown that the consumption of onions has positive effects that reduce the risks for various diseases, including many forms of cancer, vascular and heart diseases, diabetes, and ischemia. [1314151617] Pretreatment of Swiss albino mice with the methanolic extract of the outer scales and edible portion of the onion remarkably attenuated ischemia/reperfusion-induced cerebral infarct size and prevented ischemia/reperfusion-induced impairment of short-term memory and motor incoordination. This study concluded that the methanolic extract of the outer scales and edible portion of the A. cepa bulb scavenged ROS and that the anti-oxidative effect of the extract attenuated global cerebral ischemia/reperfusion-induced cerebral injury.…”