A novel hepatoprotective activity of Alangium salviifolium in mouse model.

In this study, the hepatoprotective activity of methanol bark extract of Alangium salviifolium (BEA) was evaluated for biochemical and histological parameters in swiss albino mice with CCl4-induced hepatotoxicity. The hepatomodulatory effect of two doses of BEA (20 and 50 mg/kg bw for 15 days by oral gavage) was assessed on antioxidant enzymes, phase I and phase II drug detoxifying enzymes. For the characterization of the extract, GC-MS analysis was performed that revealed the abundance of alkaloids and steroidal compounds. Total phenolic and flavonoid contents in BEA were 69.61 ± 0.18 mg GAE/g and 46.27 ± 3.44 mg Rutin/g, respectively. BEA administration decreased the levels of AST, ALT, and ALP, which were elevated due to hepatic damage by CCl4. BEA significantly decreased the lipid peroxidation, activities of LDH, and phase I enzymes including cytochrome P450 reductase, cytochrome b5 reductase while increased the activities of SOD, CAT, and phase II enzymes DT-diaphorase and glutathione S-transferase in liver. Further, histological evaluation of the liver tissue was suggestive of the protective effect of BEA against CCl4 toxicity. Together, these results suggest that BEA has strong hepatoprotective activity in mice which may also be attributed to its potential chemopreventive efficacy.

ß-Sitosterol induces G1 arrest and causes depolarization of mitochondrial membrane potential in breast carcinoma MDA-MB-231 cells.

BACKGROUNDS: It is suggested that dietary phytosterols, such as ß-sitosterol (ST), have cancer chemopreventive effects; however, studies are limited to support such claims. Here, we evaluated the efficacy of ST on three different human cancer cell lines including skin epidermoid carcinoma A431 cells, lung epithelial carcinoma A549 cells and breast adenocarcinoma MDA-MB-231. METHODS: Cell growth assay, cell cycle analysis, FACS, JC-1 staining, annexin V staining and immunoblotting were used to study the efficacy of ST on cancer cells. RESULTS: ST (30-90 µM) treatments for 48 h and 72 h did not show any significant effect on cell growth and death in A431 cells. Whereas similar ST treatments moderately inhibited the growth of A549 cells by up to 13% (p ≤ 0.05) in 48 h and 14% (p ≤ 0.05-0.0001) in 72 h. In MDA-MB-231 cells, ST caused a significant dose-dependent cell growth inhibition by 31- 63% (p ≤ 0.0001) in 48 h and 40-50% (p ≤ 0.0001) in 72 h. While exploring the molecular changes associated with strong ST efficacy in breast cancer cells, we observed that ST induced cell cycle arrest as well as cell death. ST caused G0/G1 cell cycle arrest which was accompanied by a decrease in CDK4 and cyclin D1, and an increase in p21/Cip1and p27/Kip1 protein levels. Further, cell death effect of ST was associated with induction of apoptosis. ST also caused the depolarization of mitochondrial membrane potential and increased Bax/Bcl-2 protein ratio. CONCLUSIONS: These results suggest prominent in vitro anti-proliferative and pro-apoptotic effects of ST in MDA-MB-231 cells. This study provides valuable insight into the chemopreventive efficacy and associated molecular alterations of ST in breast cancer cells whereas it had only moderate efficacy on lung cancer cells and did not show any considerable effect on skin cancer cells. These findings would form the basis for further studies to understand the mechanisms and assess the potential utility of ST as a cancer chemopreventive agent against breast cancer.

Chemopreventive effect of Lagenaria siceraria in two stages DMBA plus croton oil induced skin papillomagenesis.

Cancer chemoprevention is a dietary or therapeutic strategy to prevent, suppress, or delay carcinogenesis either at initiation or progression level with nontoxic agents. Use of natural dietary compounds has been a major chemopreventive approach to modulate tumorigenic pathways. In the present study, we have evaluated Lagenaria siceraria (bottle gourd), a common vegetable of Indian household for its chemomodulatory potential. The fruit has been used in traditional medicine for a very long time for health benefits and to cure pain, ulcers, fever, cough, asthma, and other bronchial disorders. However, despite its reported beneficial effect the chemo modulatory potential of this plant has not been reported. Therefore chemopreventive effect of bottle gourd juice (BGJ) was studied against 7,12-dimethylbenz(a)anthracene (DMBA) plus croton oil induced skin papillomagenesis in Swiss albino mice. The effect was studied both at antiinitiation and antiinitiation/promotion level followed by histopathological study. A dose of 2.5% and 5% given in drinking water showed significant decrease in papilloma number, papilloma incidence, papilloma multiplicity, papilloma latency, papilloma volume, and papilloma size in different size range. Histopathological study showed chemopreventive effect by minimizing loss of stratification, a decrease in number of epithelial layers, reducing dermal infiltration and protection for various cytoplasmic changes. Higher dose of BGJ was found to be more effective than lower dose and the chemopreventive effect was maximum for antiinitiation/promotion treatment. Altogether, this study reports the chemopreventive effect of Lagenaria siceraria on skin papillomagenesis for the first time and suggests that its consumption may help in suppression of skin cancer.

Radio-modulatory effects of green tea catechin EGCG on pBR322 plasmid DNA and murine splenocytes against gamma-radiation induced damage.

Green tea is rich in polyphenols, like catechins, which are thought to contribute to the health benefits of tea. The aim of this study was to evaluate the radioprotective effect of EGCG (epigallocatechin-3-gallate), a green tea catechin on γ-radiation induced cell damage. Under acellular condition of radiation exposure, pBR322 plasmid DNA was protected by EGCG in a concentration dependent manner. Treatment of murine splenocytes with EGCG 2h prior to radiation (3Gy), protected the cellular DNA against radiation-induced strand breaks. EGCG also inhibited γ-radiation induced cell death in splenocytes. EGCG pretreatment to the cells decreased the radiation induced lipid peroxidation and membrane damage. The levels of phase II enzymes, glutathione and lactate dehydrogenase were restored with EGCG treatment prior to radiation. Our results show that pretreatment with EGCG offers protection to pBR322 DNA under acellular condition and normal splenocytes under cellular condition, against γ-radiation induced damage and is better radioprotector in comparison to quercetin and vitamin C.

Chemomodulatory effect of Dolichos biflorus Linn. on skin and forestomach papillomagenesis in Swiss albino mice.

Effect of consumption of three different doses (2%, 4% and 6%, w/w) of Dolichos biflorus Linn. seeds on hepatic drug metabolizing enzymes, antioxidant enzymes, reduced glutathione content, lactate dehydrogenase and lipid peroxidation in Swiss albino mice has been reported. Anti-carcinogenic effect has been studied by 7,12-dimethylbenzanthracene (DMBA)-induced skin and benzo(a)pyrene[B(a)P]-induced forestomach papillomagenesis models. D. biflorus consumption resulted in a significant increase in hepatic carcinogen metabolizing enzyme systems especially at 4% and 6% doses. Significant increase in reduced glutathione content (GSH) and specific activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) in liver of mice, at 4% and 6% doses has been reported. Lactate dehydrogensae (LDH) activity and peroxidative damage has been significantly decreased at 4% and 6% doses. In skin papillomagenesis model, 4% and 6% dose in diet significantly reduced the tumor incidence (up to 25%), tumor multiplicity (up to 59%) and tumor volume per mouse (up to 70%) as compared to DMBA treated group. Importantly, significant reduction in tumor incidence (up to 33%) and tumor multiplicity (up to 61%) was evident for forestomach papillomagenesis model.

Chemomodulatory potential of Asparagus adscendens against murine skin and forestomach papillomagenesis.

We have evaluated the cancer chemopreventive efficacy of the roots of Asparagus adscendens, which have been used in the Indian traditional medicine system for a long time for the treatment of various ailments. For the first time, the effect of its different doses in a test diet was examined on 7,12-dimethylbenz(a)anthracene-induced skin and benzo(a)pyrene-induced forestomach papillomagenesis in mice. The effect of these test diets was also examined on drug-metabolizing phase I and phase II enzymes, antioxidant enzymes, reduced glutathione content, and peroxidative damage in mice. Results exhibited a significant reduction in the skin and the forestomach tumor incidence with respect to all the three (2, 4, and 6%, w/w) doses as compared with control. Among all the doses tested, 4% of test diet was most effective in protecting the animals against papillomagenesis. Further, the roots of A. adscendens inhibited phase I, and activated phase II system and antioxidant enzymes in the liver especially with 4% of test diet. The content of reduced glutathione was also significantly elevated whereas the peroxidative damage along with lactate dehydrogenase activity were reduced with all the three doses of the test diet. Together, these results suggest the cancer chemopreventive potential of A. adscendens, which could be mediated through drug-metabolizing phase I and phase II enzymes as well as free radical scavenging antioxidant enzymes.

Modulatory influence of prepubertal biochanin A exposure on mammary gland differentiation and expression of estrogen receptor-alpha and apoptotic proteins.

The modulatory influence of the phytoestrogen biochanin A, an isoflavinoid found in red clover (Trifolium pratense), on the differentiation and proliferation of mammary epithelial cells and the expression of estrogen receptor-alpha (ER-alpha) in female prepubertal Sprague-Dawley rat mammary glands was examined, for which there have been no reports to date. Biochanin A (500 microg/g bw) was injected subcutaneously on days 16, 18 and 20 post-partum. The mammary gland was dissected out and terminal end buds, terminal ducts and lobules were counted. ER-alpha, Bcl2, Bax and caspase-3 expression were determined by immunohistochemistry. Estradiol benzoate (EB) (500 ng/g bw) and dimethyl sulphoxide (DMSO) were used as the reference and vehicle, respectively. The results showed a significant enhancement of differentiation at post-natal day (PND) 21 as well as at PND 50 in the mammary glands. There was a significant decrease of ER-alpha expression at PND 21 and an increased expression of the same at PND 50, whereas increased proliferation at PND 21 and increased apoptosis at PND 50 in the mammary glands were observed in biochanin A treated animals. The mode and magnitude of the effect of biochanin A was almost similar to that of EB. These findings suggested that prepubertal exposure to biochanin A modulated the regulatory processes and in turn enhanced the differentiation and development of mammary glands in female rats. These observations may have significance in human health.

Protective effect of the cruciferous vegetable mustard leaf (Brassica campestris) against in vivo chromosomal damage and oxidative stress induced by gamma-radiation and genotoxic chemicals.

We evaluated the possible protective effect of the popular Indian cruciferous vegetable mustard leaf (Brassica campestris) against chromosomal damage and oxidative stress induced by gamma-radiation, cyclophosphamide (CPH) and urethane (URE), in mice. In vivo bone marrow micronucleus test was performed to assess chromosomal damage, and oxidative stress was monitored by estimating the changes in lipid peroxidation and the status of glutathione (GSH) as well as redox cycle antioxidants. Pretreatment with 50-250 mg/kg body wt of mustard leaf extract (MLE) for seven days significantly reduced the frequencies of micronuclei induced by gamma-radiation, CPH and URE. The protective effect against chromosomal damage was associated with modulation of lipid peroxidation as well as an increase in GSH and the GSH-dependent enzyme glutathione S-transferase (GST). Mass spectral analysis showed the presence of glucosinolates in MLE used for the pretreatment of mice. These findings indicate that intake of the green leafy cruciferous vegetable mustard leaf can lead to protection against in vivo genotoxicity and oxidative stress.

Antioxidant and non-toxic properties of Piper betle leaf extract: in vitro and in vivo studies.

Piper betle leaves are used in folk medicine for the treatment of various disorders and is commonly chewed among Asians. The present study investigates the protective efficacy of P. betle leaf extract. The presence of the extract inhibited the radiation induced lipid peroxidation process effectively. This could be attributed to its ability to scavenge free radicals involved in initiation and propagation steps. Oral supplementation with extract (1, 5 and 10 mg/kg) was administered daily for 2 weeks to Swiss albino mice and the hepatic antioxidant status was analysed. The GSH content was enhanced and no appreciable change was found in the levels of oxidative damage in terms of lipid peroxidation. Also, the specific activity of SOD increased in a dose dependent manner. These factors indicate the elevation of antioxidant status in the animals. The effect on the glyoxalase system which is considered to be activated under stress conditions was also investigated. Our findings did not observe any significant change in gly I and gly II activities, implying a non-stress condition after oral treatment of the extract. The present study indicates the antioxidant activity of P. betle leaf extract and its potential to elevate the antioxidant status.

Alterations in antioxidant enzymes and oxidative damage in experimental diabetic rat tissues: effect of vanadate and fenugreek (Trigonellafoenum graecum).

With the premise that oxygen free radicals may be responsible for the severity and complications of diabetes, the level of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as the oxidative damage were examined in the tissues of control, diabetic and treated rats. After 3 weeks of diabetes, the activity of CAT was significantly increased in heart in diabetes (about 6-fold) but decreased in liver. The SOD activity decreased significantly in liver but increased in brain. The activity of GPx decreased significantly in liver and increased in kidney. A significant increase was observed in oxidative damage in heart and kidney and a small increase in brain with decrease in liver and muscle. Vanadate and fenugreek (Trigonella foenum graecum) administration to diabetic animals showed a reversal of the disturbed antioxidant levels and peroxidative damage. Results suggest that oxidative stress play a key role in the complications of diabetes. Vanadate and fenugreek seeds showed an encouraging antioxidant property and can be valuable candidates in the treatment of the reversal of the complications of diabetes.