Bioactive polyphenols in kinkéliba tea ( Combretum micranthum ) and their glucose-lowering activities

Abstract

Herbal tea kinkéliba prepared from the leaves of Combretum micranthum has been widely consumed in West African countries for its flavor, nutritional and medicinal properties. Under bio-guided screening, the kinkéliba leaves were chemically investigated using various chromatographic and spectrometric methods that led to the identification of thirteen different flavonoid compounds. Further biological tests illustrated that the identified compounds may have synergistic effects to decrease the expression of phosphoenolpyruvate carboxykinase (PEPCK) mRNA and glucose production in an H4IIE hepatoma cell line, indicating its potential use for insulin-resistant diabetes treatment. Further in vivo study on C57BL/6J mice indicates that kinkéliba can lower plasma glucose levels in a dose-dependent manner without significant weight loss and toxicity. The ethyl acetate extract in rich of flavonoids could also increase the glucose tolerance (GT) after seven weeks' administrations. Both in vitro and in vivo experiments support a potential new application of kinkéliba leaves as an anti-diabetes agent.

Antioxidant and nephroprotection activities of Combretum micranthum: A phytochemical, in-vitro and ex-vivo studies

“…In this study, the chemical constituents isolated and identified from C. micranthum , pharmacological activities exhibited by the isolated compounds and the crude plant extracts were searched across Medline, Science Direct databases, web of science, PubMed and Google Scholar. Many authors had proved the presence of phenols (flavonoids and tannins) [62, 69, 70]. Our results corroborate these previous findings.…”

“…In vitro bioassays have shown that the identified compounds may have synergistic effects to reduce glycemia. An additional in vivo study in C57BL/6J mice indicates that C. micranthum can reduce plasma glucose levels in a dose-dependent manner without significant weight loss or toxicity [62]. These in vitro and in vivo experiments support a potential new application of C. micranthum leaves as an antidiabetic agent.…”

“…These characteristic functional groups correspond to polyphenols, flavonoids, tannins, saponins, terpenoids, alkaloids, polysaccharides and steroids [59, 60, 61]. More than thirteen different polyphenolic compounds were identificated in CM extract by HPLC methods [62]. Quantitative tests yield as total polyphenol contents (154.27 ± 3, 31 mg AG/100 g), flavonoids (333.23 ± 5.02 mg R/100 g) and tannins (21.88 ± 0.01 mg AG/100g), all confirming the effective presence of flavonoids, potentially nephroprotective [54] in CM extract.…”

Study of the Combretum micranthum G Don Sector (Kinkeliba) in Senegal

“…Vitexin and isovitexin are considered to be the major leaf flavonoids 6 linked to the hypotensive activity of the plant 7 . More recently Chika 8 and Welch 9 demonstrated the potential antidiabetic property of Combretum micranthum leaves.…”

Phenylpropanoid Glycerol Glucosides Attenuate Glucose Production in Hepatocytes

“…5 In another recent work, chlorogenic acids extracted from chicory were also shown to suppress hepatic glucose production. 9 The bulbs of the Easter lily, Lilium longiflorum Thunb., are widely used in Asian cooking and in traditional medicinal treatments. In China and Japan, the bulbs are added to culinary dishes and are also prescribed to treat inflammation, suppress coughing fits, and induce wound healing.…”