Dioscorea as the principal herb of Die-Huang-Wan, a widely used herbal mixture in China, for improvement of insulin resistance in fructose-rich chow-fed rats

• Published in: Journal of ethnopharmacology Vol. 112; no. 3; pp. 577 - 584
• Main Authors: Hsu, Jen-Hao, Wu, Yang-Chang, Liu, I-Min, Cheng, Juei-Tang
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 25.07.2007; Elsevier
• Subjects: Administration, Oral; Alisma; Alisma orientalis; Animals; bioassays; Biological and medical sciences; Blood Glucose - metabolism; chemical constituents of plants; China; Cornus officinalis; diabetes mellitus; Diabetes Mellitus, Experimental - blood; Diabetes Mellitus, Experimental - drug therapy; Die-Huang-Wan; Dietary Carbohydrates - administration & dosage; Dioscorea; Dioscorea - chemistry; Dioscorea oppositifolia; Dose-Response Relationship, Drug; Drugs, Chinese Herbal - administration & dosage; Drugs, Chinese Herbal - therapeutic use; ethnobotany; Fructose - administration & dosage; Fructose-rich chow; General pharmacology; Glucose Tolerance Test; Glucose–insulin index; herbal medicines; Hypoglycemic Agents - administration & dosage; Hypoglycemic Agents - therapeutic use; Insulin - blood; Insulin - therapeutic use; Insulin Resistance; Insulin sensitivity; Male; Medical sciences; medicinal plants; medicinal properties; Paeonia suffruticosa; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; plant extracts; Plant Extracts - administration & dosage; Plant Extracts - therapeutic use; Poria; Poria cocos; Rats; Rats, Wistar; Rehmannia glutinosa; rhizomes; roots; stems; Time Factors; Tolbutamide - administration & dosage; Tolbutamide - therapeutic use; traditional medicine; China; Asia; Insulin sensitivity; i.p; IPGTT; AUC; i.v; STZ-diabetic rats; Glucose–insulin index; Dioscorea; Die-Huang-Wan; ELISA; TCM; TZD; Fructose-rich chow; Pancreatic hormone; Monocotyledones; Rat; Glucose-insulin index; Glucose; Mixture; Medicinal plant; Protein hormone; Angiospermae; Aldose; Pharmacognosy; Rodentia; Insulin; Dioscoreaceae; Resistance; Vertebrata; Sensitivity; Mammalia; Animal; Plant origin; Herbaceous plant; Spermatophyta
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2007.05.013

The present study was designed to clarify the principal herb responsible for the improvement of insulin resistance produced by Die-Huang-Wan, a mixture of six herbs, in rats fed with fructose-rich chow for 4 weeks. A decrease in plasma glucose was observed in fructose-rich chow-fed rats received an oral administration of Die-Huang-Wan at 26 mg/kg for 60 min but it disappeared with the deletion of dioscorea ( Dioscoreae rhizoma) while this action was not modified by the deletion of other five herbs. The decrease of plasma glucose in fructose-rich chow-fed rats produced by dioscorea was similar to that treated with Die-Huang-Wan at same dosing; while the other five herbs failed to produce same influence. Similar to the effect of Die-Huang-Wan, dioscorea improved the fructose-induced decrement of insulin-stimulated glucose disposal rate after 3 days of treatment. Also, oral administration of dioscorea at effective dose (4.2 mg/kg per administration, three times daily) into streptozotocin-induced diabetic rats for 10 days increased the response to exogenous insulin, approaching to that induced by Die-Huang-Wan in same treatment. However, these effects failed to induce in the dioscorea-deleted formula of Die-Huang-Wan or other five herbs of this mixture. These results suggest that dioscorea is the major herb for the improvement of insulin sensitivity produced by Die-Huang-Wan. This can be applied to use as an adjuvant for subjects who need to increase insulin sensitivity.