Antioxidant, antiglycation and insulinotrophic properties of Coccinia grandis (L.) in vitro: Possible role in prevention of diabetic complications

Abstract

In an attempt to develop Complementary and Alternative Medicine (CAM) for the treatment of diabetes and related complications, the antidiabetic potential of the mature unripe fruits of Coccinia grandis (CGF) was evaluated. Oxidative stress and glycation plays an important role in manifesting of diabetes and vascular complications. Agents with antioxidant and antiglycation properties may retard these pathological alterations. In this study, the edible plant Coccinia grandis was assessed for in vitro estimation of antioxidant and antiglycation potential and its insulinotrophic properties in RINm5F cells. Antioxidant activity was evaluated as DPPH (1,1-diphenyl-2-picrylhydrazyl), hydrogen peroxide and superoxide anion scavenging activities, whereas the protein glycation inhibitory potential was evaluated using in vitro albumin-fructose glycation model. Glycation inhibition was estimated by different biochemical parameters viz. fructosamine, protein carbonyl group and protein aggregation using thioflavin T fluorescence. C. grandis extract exerted a dose dependent radical scavenging activity and exhibited a significant antiglycation potential. The extract also showed a significant insulinotrophic property with 1.28 and 1.71-fold increase in insulin release when compared to control at 0.25 and 0.50 mg/mL, respectively. These data suggest the possible antidiabetic role of CGF extract, presumably by its antioxidant, antiglycation and insulin secretory effects. Present findings provide experimental evidence that the fruits of C. grandis have potential antidiabetic activity which might be used as a functional food and safe remedy for the treatment of diabetes and associated complications. This study also revealed that the plant can be a promising source for development of natural antiglycating agents and novel insulin secretagogues.

Inhibitory activities of kaempferol, galangin, carnosic acid and polydatin against glycation and α‐amylase and α‐glucosidase enzymes

“…Advanced glycation end‐products generated from glycation are the ubiquitous signalling compound related with neurological and vascular complications of diabetes (Meenatchi et al ., ). Three BSA‐fructose, BSA‐MGO and arginine‐MGO were used to evaluate the antiglycation activities of kaempferol, galangin, carnosic acid and polydatin.…”

“…Advanced glycation end‐products (AGEs) are considered as the major pathogenic link between hyperglycaemia and diabetes‐related complications (Singh et al ., ). They are produced by nonenzymatic glycation through a series of reactions between reducing sugars and amine groups in amino acids, peptides or proteins (Meenatchi et al ., ). During AGE formation, highly reactive dicarbonyl compounds such as methylglyoxal (MGO) are the by‐products of glycolysis and serve as precursors in the formation (Maessen et al ., ).…”

“…During AGE formation, highly reactive dicarbonyl compounds such as methylglyoxal (MGO) are the by‐products of glycolysis and serve as precursors in the formation (Maessen et al ., ). AGEs have been reported to as pro‐inflammatory molecules, which generate free radicals to cause the pathologic complications related to diabetes (Meenatchi et al ., ). On the other hand, two important enzymes, α‐amylase and α‐glucosidase, are responsible for postprandial hyperglycaemia by catalysing the hydrolysis of carbohydrates to form glucoses in the digestive system (Thilagam et al ., ).…”

“…Current pharmaceutic treatments for diabetes are using synthetic medicines sulphonylureas, metformin and thiazolidinediones. However, they would cause serious side effects, secondary failure or loss of insulin secretory capacity (Meenatchi et al ., ). Thus, using natural compounds, such as plant phenolics to treat diabetes without concerned side effects, could be a great potential way in prevention of the disease.…”

Evaluation of in vitro sucrase Inhibitory and non-enzymatic glycation properties of Ocimum tenuiflorum L. leaves

“…The assay was done with slight modifications of a previous study (Meenatchi et al, 2017) which was also like non-enzymatic glycation by BSA-glucose model. Just for the incubation of BSA, approximately 400 µl of fructose (400 mM) was used instead of glucose.…”