Polyphenol contents in grape-seed extracts correlate with antipica effects in cisplatin-treated rats.
BACKGROUND
Grape-seed (Vitis spp.) extract (GSE) is a widely used antioxidant dietary supplement. Chemotherapeutic agents such as cisplatin induce oxidative damage in the gastrointestinal tract and cause nausea and vomiting.


METHODS
A rat model of simulated emesis was used to observe that cisplatin significantly increased kaolin consumption (or pica). Three GSEs from different sources were used in this study.


RESULTS
High-performance liquid chromatographic analysis of five major constituents (gallic acid, catechin, epicatechi, procyanidin B2, and epicatechin gallate) revealed that each constituent had different levels in the three GSEs. Extract #1, prepared in the laboratory of the investigators, had the lowest total polyphenol content (27.27 mg/g); Extract #2, obtained from a dietary supplement company in the United States, had a somewhat higher level (35.84 mg/g); and Extract #3, obtained from China, had the highest level (194.21 mg/g). Subsequently these GSEs were intraperitoneally administered in rats to evaluate their ability to decreasing cisplatin induced pica. At 10 mg/kg all three GSEs, with varying degrees of effect, decreased cisplatin-induced pica. The areas under the curves of kaolin intake from time 0 to 72 hours, compared to those in the cisplantin-only group, were reduced 45% for Extract #1 (p < 0.01), 54% for Extract #2 (p < 0.01), and 66% Extract #3 (p < 0.001).


CONCLUSIONS
The study data showed variable polyphenol contents and proportions in the three GSEs correlated to variable pharmacologic effects, indicating the importance of standardization of herbal product preparations. However further increasing of the GSE doses reversed the antipica effects of GSEs, probably because of their pro-oxidant effects. Results from this study suggest that an appropriate dose of GSE has therapeutic value in treating cisplatin-induced emesis.
Wang
Chong-Zhi
CZ
Tang Center for Herbal Medicine Research, Pritzker School of Medicine, University of Chicago, IL 60637, USA.
Fishbein
Anna
A
Aung
Han H
HH
Mehendale
Sangeeta R
SR
Chang
Wei-Tien
WT
Xie
Jing-Tian
JT
Li
Jing
J
Yuan
Chun-Su
CS
D000818:Animals; D000932:Antiemetics / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D019540:Area Under Curve; D002945:Cisplatin; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000494:pharmacology*; D008297:Male; D009325:Nausea / Q000139:chemically induced / Q000188:drug therapy; D010636:Phenols / Q000494:pharmacology*; D008517:Phytotherapy; D010842:Pica / Q000139:chemically induced / Q000188:drug therapy*; D010936:Plant Extracts / Q000494:pharmacology; D059808:Polyphenols; D051381:Rats; D017208:Rats, Wistar; D012639:Seeds; D027843:Vitis; D014839:Vomiting / Q000139:chemically induced / Q000188:drug therapy
D000932:Antiemetics; D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D002945:Cisplatin