Protein Isolate from Parkia biglobosa Seeds Improves Dyslipidaemia and Cardiac Oxidative Stress in Streptozotocin-Induced Diabetic Rats

Abstract

Reports from previous studies now provide evidence that dyslipidaemia and oxidative stress play crucial roles in the pathogenesis and progression of diabetes and its related complications. This research is aimed to investigate the potential effects of protein isolate from Parkia biglobosa seeds (PBPI) in streptozotocin (STZ)-induced diabetic rats by measuring blood glucose levels, changes in lipid metabolism and biomarkers of oxidative stress. Diabetic rats were treated orally with graded doses of PBPI, 200 mg/kg bw and 400 mg/kg bw, and 5 U/kg, intraperitoneal (i.p.) of insulin once daily for 28 days with the fasting blood glucose (FBG) monitored weekly. The effect of PBPI on the serum lipid profile was measured while the extent of lipid peroxidation (LPO), as well as antioxidant parameters (superoxide dismutase; SOD, catalase; CAT, glutathione-S-transferase; GST and total glutathione; total GSH), was determined in the cardiac homogenates of diabetic rats. At the tested doses, treatment with PBPI was significantly effective in lowering FBG, serum triglyceride, cholesterol, low-density lipoprotein cholesterol (LDL-c) and very low-density lipoprotein cholesterol (VLDL-c), while concurrently increasing high-density lipoprotein cholesterol (HDL-c). PBPI also significantly decreased the elevations witnessed in LPO levels and restored the biomarkers of oxidative stress in the cardiac homogenate of experimental rats. The results from this study demonstrate that PBPI could improve dyslipidaemia and cardiac oxidative stress in the experimental diabetic animal model possibly by reducing and effectively scavenging reactive oxygen species (ROS) production as well as by increasing antioxidant capacity in combating oxidative stress. Therefore, it can be concluded that PBPI could be explored in the development of a potent cardioprotective supplement or adjuvant therapy towards the management of diabetes and its related complications.

Effects of Allyl Isothiocyanate on Oxidative and Inflammatory Stress in Type 2 Diabetic Rats

“…Uncontrolled ROS generation impairs endogenous antioxidant defense systems such as dismutase, catalase, and peroxidase superoxide activities [ 29 ]. Such enzyme inhibition was also observed in our diabetic rats non-treated with AITC.…”

Antidiabetic Effects of Medicinal Plants

“…Decreased FBG [132,133] cholesterol, serum triglyceride, LDL-c, VLDL cholesterol and LPO with increase in HDL-c and restoration of biomarkers of OS [131]. Improvement of glucose tolerance and pancreatic β-cell function with stimulation of insulin secretion, decrease in insulin resistance, restoration of liver glycogen amelioration of serum dyslipidaemia and prevention of renal and hepatic damages in comparison to the untreated diabetic rats [132].…”

Contemporary Insights into the Biological Mechanisms of Parkia biglobosa

“…Studies have shown that Parkia biglobosa has therapeutic effects on cardiovascular disorders. Several plant parts, such as the seed [10][11][12], stem bark [32], and leaf [5,7], have been demonstrated by both empirical and scientific evidence to possess cardioprotective and hypotensive properties. Potential therapeutic mechanisms through which Parkia biglobosa exerts its effects include the augmentation of nitric oxide (NO) bioavailability and enhancement of endothelial function, both of which promote antioxidant and antiinflammatory activities.…”

“…Extracts of the leaf and/or stem bark were reported to exert antioxidant, hypotensive, cardioprotective, antihyperlipidemic, antidiabetic, antiepileptogenic, anti-amnesic, and anxiolytic-like effects in animal models [2][3][4][5][6][7], as well as antidiarrheal and antibacterial properties [8,9]. Furthermore, protein isolates from the seed exhibited hypolipidemic and cardioprotective effects [10,11], while the seeds were found to have vasorelaxant actions on smooth muscles, thereby initiating hypotensive effects [12]. A comprehensive review of the current understanding of the biological activities of Parkia biglobosa, including possible signaling pathways and mechanisms affected by the plant, is required in light of the plant's substantial significance in ethnomedicine and the scientific validation of its medicinal properties.…”

“…The observation of an increased HDL-C/LDL-C ratio in diabetic animals fed an aqueous extract of fermented Parkia biglobosa seed led to the supposition that the seed could protect against the development of cardiovascular diseases in individuals at risk [38]. It was found that protein isolates from Parkia biglobosa seeds could protect the hearts of diabetic rats by lowering blood sugar, triglycerides, and oxidative stress in the heart [11].…”