Anti-diabetic effect of American ginseng may not be linked to antioxidant activity: comparison between American ginseng and Scutellaria baicalensis using an ob/ob mice model.
Antioxidants have been considered as a useful remedy in diabetes therapeutics, and thus, herbal medicines with antioxidant properties may play major role in treating diabetes. In this report, we performed a comparative study using American ginseng and Scutellaria baicalensis to test whether the anti-diabetic effect of American ginseng is associated with its antioxidant activity. We used a simple water extraction procedure to prepare American ginseng root extract (AGE) and S. baicalensis extract (SbE), and utilized these two antioxidant herbs to evaluate their anti-diabetic effect in obese diabetic ob/ob mice. HPLC analysis was used to identify major constituents in the AGE and SbE. After 12 days of daily intraperitoneal injection, AGE at 300 mg/kg showed significant effects on fasting blood glucose levels (P<0.01) and glucose tolerance test (P<0.01) compared to vehicle-treated mice. Animal body weights also reduced significantly after 12-day treatment (P<0.01). However, SbE, a very strong antioxidant extract, administered at 5-50 mg/kg (based on our previous studies without adverse events) for 12 days did not show any significant effects on blood glucose and body weight changes. No effects were shown when baicalein, an effective antioxidant constituent in SbE, was administered at 1-5 mg/kg. It appears that the anti-diabetic effect of American ginseng may not be linked to its antioxidant actions. The mechanisms of American ginseng's effects on reducing high blood glucose levels and body weight remain to be investigated in future experiments.
Tang Center for Herbal Medicine Research, The Pritzker School of Medicine, University of Chicago, Chicago, IL 60637, USA.
Jing-Tian
JT
Xie
Chong-Zhi
CZ
Wang
Xiao-Li
XL
Li
Ming
M
Ni
Anna
A
Fishbein
Chun-Su
CS
Yuan
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D027481:Araliaceae; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy*; D004195:Disease Models, Animal; D044950:Flavanones / Q000494:pharmacology; D005951:Glucose Tolerance Test; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009765:Obesity / Q000188:drug therapy*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D018517:Plant Roots; D031364:Scutellaria baicalensis
D000975:Antioxidants; D001786:Blood Glucose; D044950:Flavanones; D007004:Hypoglycemic Agents; D010936:Plant Extracts; C006680:baicalein