Modulatory influence of Phyllanthus niruri on oxidative stress, antioxidant defense and chemically induced skin tumors.

The present study evaluates the modulatory potential of Phyllanthus niruri on chemically induced skin carcinogenesis, and its influence on oxidative stress and the antioxidant defense system. Oral administration of P. niruri extract (PNE), during peri- (Gr. III), post- (Gr. IV), or peri- and post- (Gr. V) initiational stages of 7,12-dimethylbenz(a) anthracene (DMBA)-croton oil­induced papillomagenesis considerably reduced tumor burden to 4.20, 4.00, and 3.33(positive control value 6.20); cumulative number of papillomas to 21, 16, and 10, respectively, (positive control value 62); and incidence of mice bearing papillomas to 50, 40, and 30%, respectively (positive control value 100%), but significantly increased the average latent period to 10.14, 10.62, and 11.60, and inhibition of tumor multiplicity to 66, 74,and 83%, respectively. Enzyme analysis of skin and liver showed a significant (p ≤ 0.05, ≤ 0.01, ≤ 0.001) elevation in antioxidant parameters such as superoxide dismutase, catalase, glutathione, and vitamin C in PNE-treated groups (Gr. III­V) when compared with the carcinogen-treated control (Gr. II). The elevated level of lipid peroxidation in the carcinogen-treated positive control group was significantly (p ≤ 0.05, ≤ 0.01, ≤ 0.001) inhibited by PNE administration. These results indicate that P. niruri extract has potentiality to reduce skin papillomas by enhancing antioxidant defense system.

Radiation-Induced Testicular Injury and Its Amelioration by Tinospora cordifolia (An Indian Medicinal Plant) Extract.

The primary objective of this investigation is to determine the deleterious effects of sub lethal gamma radiation on testes and their possible inhibition by Tinospora cordifolia extract (TCE). For this purpose, one group of male Swiss albino mice was exposed to 7.5 Gy gamma radiation to serve as the irradiated control, while the other group received TCE (75 mg/kg b. wt./day) orally for 5 consecutive days half an hr before irradiation to serve as experimental. Exposure of animals to 7.5 Gy gamma radiation resulted into significant decrease in body weight, tissue weight, testes- body weight ratio and tubular diameter up to 15 days of irradiation. Cent percent mortality was recorded by day 17th in irradiated control, whereas all animals survived in experimental group. TCE pretreatment rendered significant increase in body weight, tissue weight, testes- body weight ratio and tubular diameter at various intervals as compared to irradiated group. Radiation induced histological lesions in testicular architecture were observed more severe in irradiated control then the experimental. TCE administration before irradiation significantly ameliorated radiation induced elevation in lipid peroxidation and decline in glutathione concentration in testes. These observations indicate the radio- protective potential of Tinospora cordifolia root extract in testicular constituents against gamma irradiation in mice.

Amelioration of radiation-induced hematological and biochemical alterations in Swiss albino mice by Panax ginseng extract.

BACKGROUND: This study was carried out to observe the radioprotective effect of Panax ginseng root extract (PGE) against radiation-induced hematological and biochemical alterations in blood and liver of mice. Materials and methods. Adult Swiss albino mice were exposed to 6 Gy gamma radiation in the presence (experimental) or absence (control) of PGE to study the quantitative and qualitative alterations in the blood and liver. RESULTS: Radiation exposure resulted in a significant decline (P<.001) in erythrocyte count, hemoglobin (Hb), and hematocrit (Hct) in peripheral blood. Maximum changes in all the parameters were observed on day 3 after irradiation. In contrast, PGE-pretreated irradiated animals showed a significant increase in erythrocyte, Hct, and Hb values compared with irradiated controls. Furthermore, a significant elevation in lipid peroxidation level over normal was recorded in irradiated control mice, whereas this increase was considerably lesser in PGE pretreated animals. Likewise, pretreatment with PGE caused a significant increase in glutathione levels in serum as well as in liver in comparison to irradiated controls. CONCLUSION: From this study, it is clearly evident that PGE provides protection against radiation-induced hematological and biochemical alterations in Swiss albino mice.

Elimination of deleterious effects of DMBA-induced skin carcinogenesis in mice by Syzygium cumini seed extract.

The inhibition of tumor incidence by hydro-alcoholic extract of S.cumini seed was evaluated in mice on two stage process of skin carcinogenesis induced by single application of 7, 12-dimethyl benz(a)anthracene (100 µg/100µl of acetone), and 2 weeks later promoted by repeated application of croton oil (1% acetone/thrice in a week) till the end of the experiment (i.e. 16 weeks). Oral administration of extract at a dose of 250mg/kg b.wt./day at the peri-initiational stage (i.e. 7 days before and 7 days after DMBA application), promotional stage (i.e. from the time of croton oil application) and at both the stages (i.e. 7 days prior to DMBA application & continued till the end of experiment) to the mice, recorded a significant reduction in tumor incidence to 37.5, 50 & 25% respectively in comparison to the carcinogen treated control, where tumor incidence was found as 100%. Tumor yield and Tumor burden were also significantly reduced by SCE. Similarly, the cumulative number of papillomas after 16 weeks was 68 in the control group, which was reduced to 15, 21 & 8 in the animals treated with the SCE continuously at peri-, post- and peri- & post- initiation stage respectively. A significant impairment was noticed in the levels of reduced glutathione, superoxide dismutase, catalase & protein and enhancement in LPO in liver and skin of carcinogen treated control mice as compared with vehicle treated mice. All such parameters were returned to near normal value by administration of SCE to DMBA treated mice. These results suggest a possible chemopreventive property of S.cumini against DMBA induced skin carcinogenesis in mice.

Evaluation of anti-cancer and anti-oxidative potential of Syzygium Cumini against benzo[a]pyrene (BaP) induced gastric carcinogenesis in mice.

Syzygium cummini extract (SCE) was used in the present study to explore anti-tumor promoting activity in a stomach carcinogenesis model in mice. For this purpose, Swiss albino mice were administered with 1 mg of benzo-a-pyrene (BaP) in 100?l sesame oil by oral gavage twice a week for 4 consecutive weeks. The animals were sacrificed 14 weeks after the last administration of BaP. Oral administration of the extract to pre-treated (i.e. SCE as 25mg/kg b. wt./ day before BaP application for 2 weeks), post-treated (i.e. SCE after BaP application for 8 weeks) and pre-post treated (i.e. SCE for 2 weeks before treatment of BaP followed by the concomitant treatment with SCE and BaP for 4 weeks during and 2 weeks after the last dose of BaP) groups provided a significant reduction in tumor incidence, tumor burden and cumulative number of gastric carcinomas along with a significant elevation of phase II detoxifying enzymes, and inhibition of lipid per oxidation in the stomach. Thus, the present data suggest that the Syzygium cummini extract has anti-tumor and anti-oxidative potential against chemical induced stomach carcinogenesis.

Chemopreventive action of Syzygium cumini on DMBA-induced skin papillomagenesis in mice.

Syzygium cumini L. is widely used for the treatment of diabetes in various parts of India. The protective efficacy of S. cumini seed extract (SCE) against peroxidative damage contributing to skin carcinogenesis in Swiss albino mice was tested in the present study. A single topical application of 7,12-dimethyl benz(a)anthracene (100 microg/100 microl acetone), followed 2 weeks later by repeated application of croton oil (1% in acetone three times a week) and continued till the end of the experiment (i.e., 16 weeks) caused a 100% tumor incidence. In contrast, mice treated with the SCE (125 mg/ kg/ b.wt./ animal /day) in either the peri (i.e. 7 days before and 7 days after the application of DMBA) or post-initiation (i.e. from the day of start of croton oil treatment and continued till the end of the experiment) phases demonstrated significant reduction in cumulative numbers of papillomas and tumor incidence (75%). The average latency period in the SCE treated group was also significantly increased (Pre Group - 11.1 weeks; Post Group - 10.9 weeks) as compared with the carcinogen control group (7.9). Results from the present study indicate that the anticarcinogenic activity of SCE during DMBA-induced skin papillomagenesis is mediated through alteration of antioxidant status. Thus, SCE can be considered as a readily accessible, promising novel cancer chemopreventive agent.

Anti-tumor activity of Phyllanthus niruri (a medicinal plant) on chemical-induced skin carcinogenesis in mice.

Chemoprevention is an important strategy to control the process of carcinogenesis. The potential of using medicinal herbs as cancer chemopreventive nutraceuticals and functional food is promising. Thus, there is a need for exploring drugs/agents which act as chemopreventive agents. Phyllanthus niruri is a well known medicinal plant which has been used in Ayurvedic medicine as hepatoprotective, antiviral, antibacterial, analgesic, antispasmodic and antidiabetic. The present study was carried out to evaluate the anti-tumor activity of a hydro-alcoholic extract of the whole plant, in 7-9 week old male Swiss albino mice, on the two stage process of skin carcinogenesis induced by a single topical application of 7, 12-dimethylbenz (a)anthracene (100 microg/100 microl acetone) and two weeks later promoted by repeated application of croton oil (1% in acetone/three times a week) till the end of experiment (16 weeks). The oral administration of P. niruri at a dose of 1000 mg/kg/b.wt. at peri- (i.e. 7 days before and 7 days after DMBA application) and post- (i.e. starting from the croton oil application) initiational phase of papillomagenesis caused significant reduction in tumor incidence, tumor yield, tumor burden and cumulative number of papillomas as compared to carcinogen-treated controls. Furthermore, the average latent period was significantly increased in the PNE treated group. The results thus suggest that P. niruri extract exhibits significant anti-tumor activity, which supports the traditional medicinal utilization of this plant.