Anticancer activity of an Indian medicinal plant, Alstonia scholaris, on skin carcinogenesis in mice.

Alstonia scholaris, commonly known as sapthaparna, has been used for centuries in Ayurvedic medicine for treatment of various disorders. The objective of this study was to investigate the possible chemopreventive and anti-oxidative properties of this medicinal plant on two-stage process of skin carcinogenesis induced by a single application of 7, 12-dimethyabenz(a)anthrecene (100 lg/100 ll acetone), and two weeks later, promoted by repeated application of croton oil (1% in acetone/thrice a week) till the end of the experiment (16 weeks) in Swiss albino mice.The tumor incidence, tumor yield, tumor burden and cumulative number of papillomas were found to be higher in the carcinogen treated control (without ASE treatment) as compared to experimental animals (ASE treated). Furthermore, a significant increase in reduced glutathione, superoxide dismutase and catalase but decrease in lipid peroxidation was measured in ASE administered experimental groups than the carcinogen treated control. The present study demonstrates the chemopreventive potential of Alstonia scholaris bark extract in DMBA-induced skin tumorigenesis in Swiss albino mice.

Amelioration of radiation-induced hematological and biochemical alterations by Alstonia scholaris (a medicinal plant) extract.

The radioprotective efficacy of a hydro-alcoholic extracted material from the bark of Alstonia scholaris (ASE) was studied in mice against radiation-induced hematological and biochemical alterations. Swiss albino mice were administered ASE (100 mg/kg body weight/d for 5 consecutive day) orally prior to whole-body gamma irradiation (7.5 Gy). Radiation exposure resulted in a significant decline (P<.001) in erythrocytes and hemoglobin until the third day, following a gradual recovery (ie, day 7), but these values did not reach normal values during the remainder of the animals' life span. Hematocrit percentage declined significantly (P<.001) until day 15. In contrast, ASE-pretreated irradiated animals had significantly higher erythrocyte, hematocrit, and hemoglobin values than the irradiated controls. Furthermore, a significant elevation in lipid peroxidation level over normal was recorded in gamma-irradiated mice, whereas this increase was considerably lower in ASE-pretreated animals. Pretreatment with ASE caused a significant increase in glutathione levels in serum as well as in liver in comparison to irradiated animals. This study showed that ASE protects against radiation-induced hematological and biochemical alterations in Swiss albino mice.

Chemopreventive potential of an Indian medicinal plant (Tinospora cordifolia) on skin carcinogenesis in mice.

Tinospora cordifolia (Guduchi), an Indian medicinal plant, was used to explore antitumor promoting activity in a two-stage skin carcinogenesis model. For this purpose, mice were treated by single application of DMBA (100 microg/100 microl of acetone) and two weeks later promoted by croton oil (1% in acetone three times a week) until the end of the experiment (i.e., 16 weeks). Oral administration of the above extract at the preinitiational stage (i.e., seven days before and seven days after DMBA application; group IV), promotional stage (i.e., from the time of croton oil application; group V), and both pre- and postintiational stage (i.e., from the time of DMBA application and continued until the end of the experiment; group VI; on the shaven backs of the mice at the dose of 100 mg/kg body weight/day for 16 weeks) recorded significant reduction in tumor weight, tumor incidence in comparison to control (i.e., mice treated with DMBA and croton oil; group III). Furthermore, cumulative number of papillomas, tumor yield, tumor burden, and tumor weight showed significant reduction along with significant elevation of phase II detoxifying enzymes, and inhibition of lipid peroxidation in liver and skin in the animals administered with such plant extract concomitant to carcinogen exposure. Thus, the present data strongly suggests that the Tinospora cordifolia extract has anti-tumor potential in a two-stage skin carcinogenesis mouse model.