stilbenes and Ear-Diseases

Carcinogenesis is a complex process and at least 3 stages, including initiation, promotion, and progression, have been proposed in the process of carcinogenesis. Resveratrol has attracted considerable attention due to its low toxicity and unique chemical structure. This study was designed to test chemopreventive effect of resveratrol to cancer using various animal models.. Ames assay and micronucleus formation assay were used to test the antimutagenic activities of resveratrol. Croton oil-induced enhancement of ornithine decarboxylase (ODC) activities of dorsal epidermis cells in mouse and mouse ear edema model were used to investigate the anti-promotion effect of resveratrol. In addition,7,12-dimenthylbenz[a]anthracene (DMBA)/croton oil-induced mouse skin tumor model was used to evaluate chemopreventive effect of resveratrol to cancer in vivo.. In Ames test,100 microg/plate of resveratrol exhibited 42.2% of inhibition on the reversion of Salmonella typhimurium TA100 induced by methylmethansulfonate, and 200 microg/plate of resveratrol exhibited 91.8% of inhibition on the reversion induced by benzopyrene. Pretreatment of resveratrol prevented cyclophosphamide (CTX)-induced micronucleus formation of polychromatic erythrocytes of mice bone marrow in dose-dependent manner. Mice treated with 30 mg/kg of resveratrol for 6 days before croton oil exposure have palliative ear edema. Treatment of 180 mg/kg resveratrol for 3 days caused 69.3% decrease of ODC activities in croton oil-induced dorsal epidermis. It was shown that resveratrol could inhibit DMBA/croton oil-induced mouse skin papilloma, which includes prolonging the latent period of tumor occurrence, decreasing the incidence of papilloma, and reducing tumor number per mouse in dose-dependent manner.. Resveratrol has the ability of anti-mutation and anti-promotion of cancer and merit further studies as a potential cancer chemopreventive agent.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Anticarcinogenic Agents; Antimutagenic Agents; Croton Oil; Ear Diseases; Edema; Epithelial Cells; Female; Male; Mice; Mice, Inbred ICR; Micronucleus Tests; Mutagenicity Tests; Ornithine Decarboxylase; Papilloma; Resveratrol; Salmonella typhimurium; Skin Neoplasms; Stilbenes

To investigate the expression of matrix metalloproteinase-9 (MMP-9) in mouse ears induced with croton oil and the inhibitory effect of dexamethasone, indomethacin and resveratrol on MMP-9 expression, and further explore the relationship between anti-inflammation and MMP-9 inhibition of these three medicines.. Immuno-histochemistry was used to detect the expression of MMP-9 in mouse ears. Expression of MMP-9 in U937 cells was analyzed by gelatin zymography.. Mouse ear edema induced with croton oil was inhibited significantly by dexamethasone and indomethacin at the dose of 10 mg.kg-1 and resveratrol at 50 mg.kg-1 administered subcutaneously. The inhibitory rate was 76.2% (P < 0.001), 56.7% (P < 0.001) and 36.9% (P < 0.001) respectively. The MMP-9 expression increased in mouse ears induced with croton oil and inhibited by dexamethasone, indomethacin and resveratrol at above doses. Gelatin zymography results showed that MMP-9 expression in U937 cells increased significantly after exposed to PMA at 1 x 10(-8) mol.L-1 (P < 0.001); MMP-9 expression induced with phorbol myristate acetate(PMA) was inhibited by dexamethasone at 1 x 10(-9), 1 x 10(-7) and 1 x 10(-5) mol.L-1, indomethacin at 1 x 10(-6) and 1 x 10(-5) mol.L-1 and resveratrol at 1 x 10(-6) and 1 x 10(-5) mol.L-1.. The inhibition of MMP-9 expression may be one of the anti-inflammatory mechanisms of dexamethasone, indomethacin and resveratrol.

Topics: Animals; Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; Croton Oil; Dexamethasone; Ear Diseases; Edema; Humans; Indomethacin; Male; Matrix Metalloproteinase 9; Matrix Metalloproteinase Inhibitors; Mice; Mice, Inbred ICR; Random Allocation; Resveratrol; Stilbenes; U937 Cells