Antioxidant Properties and Digestive Enzyme Inhibitory Activity of the Aqueous Extract from Leafy Stems of Cissus polyantha.

Mahamad Abba Talba,Albert Kamanyi,Sylviane Laure Poualeu Kamani,Sylvie Léa Wansi,David Miaffo

doi:10.1155/2019/7384532

Abstract

Cissus polyantha (Vitaceae) is a plant used in Cameroonian traditional medicine for the treatment of diabetes. The aims of this study were to evaluate the in vitro antioxidant and antidiabetic activities of the aqueous extract of Cissus polyantha leafy stems. The enzyme inhibitory activity was determined in vitro on α-amylase and α-glucosidase enzymes, followed by confirmative study in vivo on normal rats (oral starch and sucrose tolerance tests at doses of 111, 222, and 444 mg/kg). The ferric reducing antioxidant power and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) antiradical activity of the extract were examined to evaluate the antioxidant potential of the extract. The total content of phenols, flavonoids, and tannins of the extract were also determined. The results showed an inhibitory effect of the extract on the α-amylase and α-glucosidase activities with IC50 values of 216.14 and 182.40 μg/mL, respectively. The extract at doses of 222 and 444 mg/kg induced a significant decrease in postprandial glycaemia during the starch and sucrose tolerance tests. A remarkable antiradical activity of the extract was obtained although lower than that of the standard product. The aqueous extract of leafy stems of Cissus polyantha has an interesting inhibitory activity on the α-amylase and α-glucosidase enzymes, as well as an antioxidant potential, thus validating its use in traditional medicine for the treatment of diabetes mellitus and its complications.

Highlights

Type 2 diabetes mellitus is a metabolic disease characterized by increasing in insulin resistance and decreased beta cell function and chronic hyperglycemia
E tannin content (0.82 ± 0.5 mg CE/g dry wt.) was evaluated using catechin as standard. ese results revealed that the aqueous extract of Cissus polyantha contains phenols, flavonoids, and tannins at varying proportions
Acarbose has shown a significant inhibitory potential with inhibition percentages ranging between 7.98% and 49.30%, while the extract showed an inhibitory activity of 3.12% to 41.66% corresponding to concentrations ranging from 1 to 200 μg/mL. e IC50 values of extract and acarbose were 195.07 ± 1.44 and 216.14 ± 0.83 μg/mL, respectively

Summary

Introduction

Type 2 diabetes mellitus is a metabolic disease characterized by increasing in insulin resistance and decreased beta cell function and chronic hyperglycemia. It is responsible for the nonregulation of postprandial hyperglycemia which is a major factor of the cardiovascular complications [1]. Several plants have already shown their antioxidant and/or inhibitory potentials on the activity of α-amylase and α-glucosidase enzymes, such as Retama raetam [5], Picralima nitida [6], and Combretum molle [7]. E present study aims to quantify the polyphenols, flavonoids, and tannins in the aqueous extract from leafy stems of Cissus polyantha, to determine its antioxidant potential and to evaluate its inhibitory properties on the α-amylase and α-glucosidase activities Qualitative phytochemical studies have reported that C. polyantha leaves contains quinoids, sterols, terpenes, saponins, phenols, tannins, and flavonoids [10]. e present study aims to quantify the polyphenols, flavonoids, and tannins in the aqueous extract from leafy stems of Cissus polyantha, to determine its antioxidant potential and to evaluate its inhibitory properties on the α-amylase and α-glucosidase activities

Materials and Methods

In Vitro Enzyme Inhibition Study

In Vitro Antioxidant Tests

Results