Diphlorethohydroxycarmalol isolated from Ishige okamurae, a brown algae, a potent α-glucosidase and α-amylase inhibitor, alleviates postprandial hyperglycemia in diabetic mice

• Published in: European journal of pharmacology 2009-08, Vol.615 (1), p.252-256
• Main Authors: Heo, Soo-Jin, Hwang, Ji-Young, Choi, Jung-In, Han, Ji-Sook, Kim, Hak-Ju, Jeon, You-Jin
• Format: Article
• Language: English
• Subjects: alpha-Amylases - antagonists & inhibitors; Animals; Area Under Curve; Biological and medical sciences; Blood Glucose - analysis; Cell Survival - drug effects; Diabetes; Diabetes Mellitus, Experimental - drug therapy; Diabetes. Impaired glucose tolerance; Diphlorethohydroxycarmalol; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Endothelial Cells - drug effects; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Glycoside Hydrolase Inhibitors; Heterocyclic Compounds, 3-Ring - isolation & purification; Heterocyclic Compounds, 3-Ring - pharmacology; Heterocyclic Compounds, 3-Ring - therapeutic use; Humans; Hyperglycemia - drug therapy; Hypoglycemic Agents - pharmacology; Hypoglycemic Agents - therapeutic use; In Vitro Techniques; Medical sciences; Mice; Phaeophyceae - chemistry; Pharmacology. Drug treatments; Phytotherapy; Plant Extracts - pharmacology; Plant Extracts - therapeutic use; Postprandial hyperglycemia; Postprandial Period; Umbilical Veins - cytology; α-amylase; α-glucosidase
• ISSN: 0014-2999; 1879-0712
• DOI: 10.1016/j.ejphar.2009.05.017

This study was designed to investigate whether diphlorethohydroxycarmalol (DPHC) may inhibit α-glucosidase and α-amylase activities, and alleviate postprandial hyperglycemia in streptozotocin-induced diabetic mice. DPHC isolated from Ishige okamurae, a brown algae, evidenced prominent inhibitory effect against α-glucosidase and α-amylase. The IC 50 values of DPHC against α-glucosidase and α-amylase were 0.16 and 0.53 mM, respectively, which evidenced the higher activities than that of acarbose. DPHC did not exert any cytotoxic effect in human umbilical vein endothelial cells (HUVECs) at various concentrations (from 0.49 to 3.91 mM). The increase of postprandial blood glucose levels were significantly suppressed in the DPHC-administered group than those in the streptozotocin-induced diabetic or normal mice. Moreover, the area under curve (AUC) was significantly reduced via DPHC administration (2022 versus 2210 mmol∙min/l) in the diabetic mice as well as it delays absorption of dietary carbohydrates. Therefore, these result indicated that DPHC might be a potent inhibitor for α-glucosidase and α-amylase.