Identification of Pinocembrin as an Anti-Glycation Agent and α-Glucosidase Inhibitor from Fingerroot (Boesenbergia rotunda): The Tentative Structure–Activity Relationship towards MG-Trapping Activity

Abstract

Diabetes mellitus (DM) is a disease that is caused by a malfunction of carbohydrate metabolism, which plays an important role in the development of long-term diabetic complications. The excess glucose can be transformed to methylglyoxal (MG), a potential precursor of glycation. Glycation is a spontaneous non-enzymatic reaction that initially yields advanced glycation end-products (AGEs), which ultimately triggers several severe complications. Therefore, the inhibition of AGEs formation is the imperative approach for alleviating diabetic complications. The aim of this research was to investigate the glycation and α-glucosidase inhibitory abilities of compounds isolated from fingerroot. The dichloromethane extract afforded three flavanones, two chalcones, two dihydrochalcones, and one kavalactone. Most of the isolated compounds showed higher inhibition effect against AGEs formation than aminoguanidine (AG). Subsequent evaluation in MG-trapping assay indicated that their trapping potency was relatively comparable to AG. Their structure-activity relationships (SAR) of MG-trapping activity were investigated using the comparison of the structures of flavonoids. In addition, pinocembrin displayed moderate α-glucosidase inhibition against both maltase and sucrose, with IC50 values of 0.35 ± 0.021 and 0.39 ± 0.020 mM, respectively.

In Vitro Antidiabetic Activity Affecting Glucose Uptake in HepG2 Cells Following Their Exposure to Extracts of Lauridia tetragona (L.f.) R.H. Archer

“…The inhibition of DPPIV to increase the half-life of GLP1 and stimulation of the peripheral response to insulin-thereby increasing the overall effects of the GLP1-insulin signaling-has also been reported [31]. Different reports have also described the inhibitory potentials of polyphenols as potent inhibitors of specific targets related to type 2 diabetes physiopathology, including protein tyrosine phosphatase 1B (PTP1B), DPPIV, and sodium-glucose cotransporter 2, among many other targets [32][33][34]. The oral administration of ferulic acid (50 mg/kg) has been reported to significantly decrease blood glucose levels and increase plasma insulin levels in type 2 diabetic mice by elevating hepatic glycogen synthesis and glucokinase activity [31].…”

Effect of Pholiota nameko Polysaccharides Inhibiting Methylglyoxal-Induced Glycation Damage In Vitro

“…Reactive carbonyl species in the glycation process, such as 3-deoxyglucosone, glyoxal, and MG, play a critical role in mediating glycation stress in human cells and are associated with various chronic diseases and cancer [41,42]. Some studies have described MG as the most important precursor for the formation of AGEs during glycation.…”

The Antioxidant, Anti-Inflammatory, and Neuroprotective Properties of the Synthetic Chalcone Derivative AN07

“…Accumulating in vitro studies have shown that dietary flavonoids inhibit the formation of AGEs by trapping MG, the reactive dicarbonyl species precursor of AGEs [ 17 ], under physiological conditions [ 69 , 70 , 71 , 72 ]. Based on the observations on different flavonoids, compounds with the catechin-like A-ring structure showed the most potent effect on direct trapping of MG.…”