In vitro anti-diabetic activity of flavonoids and pheophytins from Allophylus cominia Sw . on PTP1B, DPPIV, alpha-glucosidase and alpha-amylase enzymes

Abstract

BackgroundEthno-botanical information from diabetic patients in Cuba led to the identification of Allophylus cominia as a possible source of new drugs for the treatment of type 2 diabetes mellitus (T2-DM). ExperimentalChemical characterization of the extracts from A. cominia was carried out using chromatographic and spectroscopic methods. The extracts were tested for their activity on PTP1B, DPPIV, α-glucosidase enzymes and α-amylase. ResultsThe flavonoid rich fractions from A. cominia inhibited DPPIV enzyme (75.3±2.33%) at 30 µg/ml and produced a concentration-dependent inhibition against DPPIV with a Ki value of 2.6 µg/ml. At 30 µg/ml, flavonoids and pheophytins extracts significantly inhibited PTP1B enzyme (100±2.6% and 68±1% respectively). The flavonoids, pheophytin A and pheophytin B fractions showed significant concentration-dependent inhibition against PTP1Bwith Ki values of 3 µg/ml, 0.64 µg/ml and 0.88 µg/ml respectively. At 30 µg/ml, the flavonoid fraction significantly inhibited α-glucosidase enzyme (86±0.3%) in a concentration-dependent pattern with a Ki value of 2 µg/ml.None of the fractions showed significant effects on α-amylase. Fatty acids, tannins, pheophytins A and B, and a mixture of flavonoids were detected in the methanolic extract from A. cominia. The identified flavonoids were mearnsitrin, quercitrin, quercetin-3-alloside, and naringenin-7-glucoside.

In vitro anti-diabetic effect of flavonoids and pheophytins from Allophylus cominia Sw . on the glucose uptake assays by HepG2, L6, 3T3-L1 and fat accumulation in 3T3-L1 adipocytes

“…As explained in a previous report of the same study (Semaan et al, 2017), the phytochemical separation and identification of the compounds from the Cuban plant Allophylus cominia revealed the existence of a mixture of flavonoids (quercetrin and mearnsitrin, in addition to other minor flavonoids and fat) and a mixture of pheophytins (a and b). However, of the extracts fractionated from A.comina, all were investigated for anti-enzyme activities (DPPIV, PTP1B, α-glucosidase and α-amylase) (Semaan et al, 2017). The effect of fractions that showed more than 70% inhibition of PTP1B enzyme activity on glucose uptake was subsequently investigated using various cell lines.…”

“…It is possible that the inhibition of PTP1B contributed to the enhancement of the glucose uptake as well as to the enhancement of insulin sensitivity in differentiated 3T3-L1, L6 and HepG2 cells. The mixture of flavonoids produced the greatest effect on glucose uptake, with 100% inhibition of PTP1B enzyme (Semaan et al, 2017). PTP1B enzyme inhibition enhanced insulin activity of A. cominia by this mechanism.…”

Bioactivity, Compounds Isolated, Chemical Qualitative, and Quantitative Analysis of Cymbaria daurica Extracts

“…The anti-inflammatory and anti-diabetic activities of C. daurica can be attributed to the bioactive compounds. Phenylethanoid glycosides, flavonoids, and iridoids exhibit extensive pharmacological activities, including antiinflammatory (Hanfer et al, 2017;Spagnuolo et al, 2018;Zhang et al, 2018) and anti-diabetic activities (Miura et al, 1996;Semaan et al, 2017). Verbascoside has been the subject of biological studies demonstrating anti-inflammatory activity in several models, such as the intestinal inflammation model, where it decreased the presence of pro-inflammatory molecules (Carrillo-Ocampo et al, 2013).…”

Dataset on the kinetics of the inhibition of PTP1B by the flavonoids and pheophytin A from Allophylus cominia

“…Various concentrations of A. cominia extract (both flavonoids and pheophytins, concentration range 0.01–30 µg/ml) were incubated with PTP1B enzyme (2 nM) at 37 °C for 30 min [3] . Various concentrations of PTP1B substrate (DiFMUP, concentration range 0–40 µM) was added and incubated at 37 °C in an atmosphere containing 5% CO 2 for another 10 min.…”