Erythritol attenuates postprandial blood glucose by inhibiting α-glucosidase

This work was supported by grants from Natural Science Foundation of Qinghai (No. 2016-ZJ-942Q), West Light Foundation of the Chinese Academy of Sciences (No. Y629071211), National Natural Science Foundation of China (No. 31701243), International Cooperative Projects of Qinghai province (No. 2017-HZ-811), Project of Discovery, Evaluation and Transformation of Active Natural Compounds, Strategic Biological Resources Service Network Program of Chinese Academy of Sciences (No. ZSTH-027), Major Special Science and Technology Projects in Qinghai Province (2014-GX-A3A-01).Diabetes mellitus (DM) is a serious metabolic disorder where impaired postprandial blood glucose regulation often leads to severe health complications. The natural chemical, erythritol is a C4 polyol approved by FDA for use as a sweetener. Here we examined a potential role for erythritol in the control of postprandial blood glucose levels in DM. An anti-postprandial hyperglycemia effect upon erythritol administration (500 mg kg-1) was demonstrated in alloxan-induced DM model mice by monitoring changes in blood glucose after intragastric administration of drugs and starch. We also found that erythritol most likely exerts its anti-postprandial hyperglycemic activities by inhibiting α-glucosidase in a competitive manner. This was supported by enzyme activity assays and molecular modelling experiments. In the latter experiments it was possible to successful dock erythritol into the catalytic pocket of α-glucosidase, with the resultant interaction likely to be driven by electrostatic interactions involving Asp 215, Asp69 and Arg446 residues. This study suggests that erythritol may not only serve as a glucose substitute but may also be a useful agent in the treatment of diabetes mellitus to help manage postprandial blood glucose levels.PostprintPeer reviewe

Two new isoquinoline alkaloids from <i>Hypecoum leptocarpum</i> Hook. f. et Thoms

Two new isoquinoline alkaloids, hypecocarpinine (1) and leptocaramine (2) along with five known ones including leptopidine (3), corydamine (4), protopine (5), dihydroprotopine (6) and oxohydrastinine (7), were isolated from Hypecoum leptocarpum Hook. f. et Thoms. Structures of the compounds were elucidated using spectroscopic methods, including UV, IR, HR-ESI-MS, 1 D and 2 D NMR. The cytotoxic activities of these compounds were evaluated using MTT assay. The results showed that compounds 2, 4, and 7 have moderate cytotoxicity against human lung cancer (A549) and human gastric carcinoma (MGC-803) cell lines.</p

Targeted Separation of COX-2 Inhibitor from <i>Pterocephalus hookeri</i> Using Preparative High-Performance Liquid Chromatography Directed by the Affinity Solid-Phase Extraction HPLC System

Pterocephalus hookeri, as a kind of popular traditional Tibetan medicine, is reputed to treat inflammatory related diseases. In the present work, a cyclooxygenase-2 functionalized affinity solid-phase extraction HPLC system was developed and combined with preparative-HPLC for rapidly screening and separating cyclooxygenase-2 ligand from P. hookeri extracts. Firstly, ligands of cyclooxygenase-2 were screened from extracts by affinity solid-phase extraction HPLC system. Then directed by the screening results, the recognized potential active compounds were targeted separated. As a result, the major cyclooxygenase-2 inhibitor of P. hookeri was obtained with a purity of >95%, which was identified as sylvestroside I. To test the accuracy of this method, the anti-inflammatory activity of sylvestroside I was inspected in lipopolysaccharide-induced RAW 264.7 cells. The results show that sylvestroside I significantly suppressed the release of prostaglandin E2 with dose-dependent, which was in good agreement with the screening result of the affinity solid-phase method. This method of integration of screening and targeted separation proved to be very efficient for the recognition and isolation of cyclooxygenase-2 inhibitors from natural products

Erythritol attenuates postprandial blood glucose by inhibiting α-glucosidase

Diabetes mellitus (DM) is a serious metabolic disorder where impaired postprandial blood glucose regulation often leads to severe health complications. The natural chemical, erythritol is a C4 polyol approved by FDA for use as a sweetener. Here we examined a potential role for erythritol in the control of postprandial blood glucose levels in DM. An anti-postprandial hyperglycemia effect upon erythritol administration (500 mg kg-1) was demonstrated in alloxan-induced DM model mice by monitoring changes in blood glucose after intragastric administration of drugs and starch. We also found that erythritol most likely exerts its anti-postprandial hyperglycemic activities by inhibiting α-glucosidase in a competitive manner. This was supported by enzyme activity assays and molecular modelling experiments. In the latter experiments it was possible to successful dock erythritol into the catalytic pocket of α-glucosidase, with the resultant interaction likely to be driven by electrostatic interactions involving Asp 215, Asp69 and Arg446 residues. This study suggests that erythritol may not only serve as a glucose substitute but may also be a useful agent in the treatment of diabetes mellitus to help manage postprandial blood glucose levels