Voglibose for prevention of type 2 diabetes mellitus

Zhang

et al. 2015

J. Agric. Food Chem.

Polyphenols and caffeoylquinic acid (CQA) derivatives (3-CQA, 4-CQA, 5-CQA, 3,4-diCQA, 3,5-diCQA, and 4,5-diCQA) were prepared from Ilex kudingcha C.J. Tseng, and their effects and mechanisms on the activities of α-glucosidase from Saccharomyces cerevisiae were investigated in the present study. As results, the IC50 values for CQA derivatives were 0.16-0.39 mg/mL, and the inhibition mode of CQA derivatives was noncompetitive. On the basis of fluorescence spectroscopy and circular dichroism spectroscopy data, the binding constants and number of binding sites were calculated to be 10(6)-10(8) M(-1) and 1.42-1.87, respectively. CQA derivatives could bind to the enzyme mainly through hydrophobic interaction, altering the microenvironment and molecular conformation of the enzyme, thus decreasing the catalytic activity. To the authors' knowledge, this is the first report on α-glucosidase inhibitory mechanism by CQA derivatives from I. kudingcha, and the findings suggest a potential use of kudingcha as functional foods for the prevention and treatment of diabetes and related symptoms.

Section: ■ Introductionmentioning

confidence: 99%

Inhibitory Activities of Caffeoylquinic Acid Derivatives from Ilex kudingcha C.J. Tseng on α-Glucosidase from Saccharomyces cerevisiae

Xü

Zhang

et al. 2015

J. Agric. Food Chem.

“…Diabetes mellitus (DM) type 2 is one of the serious chronic diseases in the world, which incurs a big economic and social burden [1][2].The control of the postprandial hyperglycemia is the key to preventing and curing type 2 DM and is usually achieved by inhibiting the digestive enzymes of carbohydrates such as αglucosidase and α-amylase [3,4]. Synthetic α-glucosidase inhibitors, such as acarbose and voglibose, were the main oral drugs fortype 2 DM [5,6], but due to their potential toxicity and significant side effects, the need for natural inhibitors from plants is increasing [7,8]. It was reported that the 50% ethanol eluate of Chimonanthus nitens Oliv.…”

mentioning

confidence: 99%

Inhibitory Mechanism of Taxifolin against α-Glucosidase Based on Spectrofluorimetry and Molecular Docking

Liu

Natural Product Communications

Geng

et al. 2017

The α-glucosidase inhibitory activity and behavior of taxifolin was first investigated by spectrofluorimetry and molecular docking. It was found that taxifolin inhibits α-glucosidase in a competitive manner with the IC 50 value of 0.16 mg/mL. The intrinsic fluorescence quenching of α-glucosidase in the presence of taxifolin was observed by the static quenching mechanism. According to the thermodynamic study, the complex of taxifolin and α-glucosidase was maintained by van der Waals and hydrogen bonding. The binding mode provided by molecular docking simulation indicated the existence of hydrogen bonding between taxifolin and the amino acid residues of α-glucosidase (Glu429, Asp 568 and Glu771), which coincided with the result of fluorescence analysis.

“…erefore, we speculated that TZQ might retard the absorption of glucose by the inhibition of carbohydrate hydrolyzing enzymes of maltase, sucrase, and α-amylase in the digestive organs ( Figure 7). e postprandial hypoglycemic mechanisms of TZQ might be similar to the inhibitory activities of acarbose against intestinal sucrase and pancreatic α-amylase [38] and the inhibitory activities of voglibose against intestinal sucrase and maltase [39]. A further in vitro study will be implemented to determine changes in the activity and secondary structure of the α-glucosidases inhibited by TZQ.…”

Section: Evidence-based Complementary and Alternative Medicinementioning

confidence: 99%

Alleviating the Hydrolysis of Carbohydrates, Tangzhiqing (TZQ) Decreased the Postprandial Glycemia in Healthy Volunteers: An Eight‐Period Crossover Study

Evidence-Based Complementary and Alternative Medicine

et al. 2020

Tangzhiqing (TZQ), a Chinese herbal medicine, has been widely used to treat diabetes mellitus in China. TZQ works as a potential α-glucosidase inhibitor to reduce the absorption of glucose from dietary carbohydrates. The main aim of this study was to investigate the postprandial glucose-lowering effect of TZQ on the common carbohydrates in healthy humans. Meanwhile, the possible types of the inhibited α-glucosidase enzymes were predicted in this study. Glucose, sucrose, maltose, maltodextrin, and starch were chosen as investigated carbohydrates. The baseline incremental area under the curve (IAUC) and glycemic index (GI) values of the investigated carbohydrates were evaluated. Then, thirty-six subjects were randomly assigned to three groups to assess postprandial hypoglycemic effects of 3-, 6-, and 9-tablet TZQ. The subjects in each group were randomized to eight subgroups. An eight-period, eight-sequence, crossover design was performed to investigate the postprandial glucose-lowering effect of TZQ after drinking each carbohydrate. A significant decrease was observed on the postprandial glucose IAUCs (279.41 ± 111.31 vs. 203.86 ± 61.08) and GIs (124.91 ± 48.54 vs. 91.69 ± 27.47) of maltose after oral administration of 6-tablet TZQ, as well as IAUCs (145.05 ± 55.01 vs. 110.23 ± 57.03) and GIs (84.87 ± 33.40 vs. 65.50 ± 33.89) of sucrose after administration of 3-tablet TZQ. The glucose IAUCs (109.15 ± 55.92 vs. 57.68 ± 46.09) and GIs (49.09 ± 25.15 vs. 25.94 ± 20.73) of starch statistically reduced following the administration of 6-tablet TZQ. The lowering postprandial blood glucose effect of TZQ did not increase proportionally with increasing doses in humans. There were no significant changes in the glucose-lowering effect of glucose and maltodextrin after the administration of 3-, 6-, or 9-tablet TZQ, respectively. TZQ is a potential treatment for postprandial hyperglycemia, which can probably make α-glucosidases inhibit maltase, sucrase, and α-amylase in the digestive organs.