Showing papers on "7,12-Dimethylbenz[a]anthracene published in 2013"
TL;DR: NARNPs have more potent anti-lipid peroxidative, antiproliferative effect and antioxidant potentials compared to free NAR in DMBA-induced oral carcinogenesis and could be a potentially useful drug carrier system for targeted delivery of naringenin for cancer chemoprevention.
Abstract: Nanochemoprevention has been introduced recently as a novel approach for improving phytochemicals bioavailability and anti-tumor effect. The present study is designed to evaluate the chemopreventive efficacy of prepared naringenin-loaded nanoparticles (NARNPs) relative to efficacy of free naringenin (NAR) against 7,12-dimethyl benz(a)anthracene (DMBA)-induced oral carcinogenesis by evaluating the status of lipid peroxidation, antioxidants and immunoexpression patterns of proliferating cell nuclear antigen (PCNA) and p53 proteins. Transmission electron microscope (TEM) and dynamic light scattering (DLS) investigations have confirmed a narrow size distribution of the prepared nanoparticles (40–90 nm) with ~88 % encapsulation efficiency. Oral squamous cell carcinoma (OSCC) was developed in the buccal pouch of golden Syrian hamsters by painting with 0.5 % DMBA in liquid paraffin three times a week for 14 weeks. DMBA painted animals revealed the morphological changes, hyperplasia, dysplasia and well-differentiated squamous cell carcinoma. Moreover, the status of lipid peroxidation, antioxidants and immunoexpression of PCNA and p53 were significantly altered during DMBA-induced oral carcinogenesis. Oral administration of NARNPs (50 mg NAR/kg body weight/day) to DMBA-treated animals completely prevented the tumor formation as compared to the free NAR and significantly reduced the degree of histological lesions, in addition to restoration of the status of biochemical and molecular markers during oral carcinogenesis. In addition, NARNPs have more potent anti-lipid peroxidative, antiproliferative effect and antioxidant potentials compared to free NAR in DMBA-induced oral carcinogenesis. In conclusion, the present study suggests that NARNPs could be a potentially useful drug carrier system for targeted delivery of naringenin for cancer chemoprevention.
66 citations
TL;DR: It is suggested that apigenin exhibited anti-cell proliferative, anti-inflammatory,Anti-angiogenic and apoptotic potential during DMBA-induced hamster buccal pouch carcinogenesis.
39 citations
TL;DR: Chrysin has the potential to delay rather than inhibit tumor formation as evidenced by the tumor formation in two of the DMBA + chrysin-treated hamsters, during DMBA-induced hamster buccal pouch carcinogenesis.
Abstract: Introduction: Chemoprevention, an emerging, appealing, and innovative approach in experimental oncology, deals with the inhibition, prevention or suppression of carcinogenesis, using natural products or synthetic derivatives. The aim of the present study is to investigate the chemopreventive potential of chrysin during 7,12-dimethylbenza[a]anthracene (DMBA) - induced hamster buccal pouch carcinogenesis. Materials and Methods: Oral squamous cell carcinoma was developed in the buccal pouch of Syrian golden hamsters by painting them with 0.5 percent DMBA in liquid paraffin thrice a week, for 14 weeks. The status of lipid peroxidation, antioxidants, and phase I and II detoxification agents were utilized as biochemical end points, to assess the chemopreventive efficacy of chrysin in DMBA-induced hamster buccal pouch carcinogenesis. Results: In the present study, 100% tumor formation with marked abnormalities in the status of lipid peroxidation, antioxidants, and detoxification agents was noticed in hamsters treated with DMBA alone. Oral administration of chrysin at a dose of 250 mg/kg bw to DMBA-treated hamsters significantly reduced the tumor incidence and tumor size as well as reverted the status of the above-mentioned biochemical markers during DMBA-induced hamster buccal pouch carcinogenesis. Conclusion: Chrysin has the potential to delay rather than inhibit tumor formation as evidenced by the tumor formation in two of the DMBA + chrysin-treated hamsters, during DMBA-induced hamster buccal pouch carcinogenesis.
29 citations
TL;DR: Though oral administration of saffron completely prevented the formation of tumors, it was noticed severe hyperplasia and dysplasia in hamsters treated with DMBA, suggesting that tumors might eventually develop.
Abstract: Our aim was to investigate the chemopreventive potential of saffron in DMBA-induced hamster buccal pouch carcinogenesis. Assessment was by monitoring the percentage of tumor bearing hamsters, tumor size as well as the status of detoxification agents, lipid peroxidation and antioxidants. Oral squamous cell carcinomas were induced in the buccal pouch of Syrian golden hamsters by painting them with 0.5% DMBA in liquid paraffin three times a week for 14 weeks. We observed 100% oral tumor formation with severe histopathological abnormalities in all the hamsters treated with DMBA alone, activities of phase I and phase II detoxification enzymes, lipid peroxidation and antioxidants being significantly altered. Though oral administration of saffron completely prevented the formation of tumors, we noticed severe hyperplasia and dysplasia in hamsters treated with DMBA, suggesting that tumors might eventually develop. Oral administration of saffron return detoxification enzymes, lipid peroxidation and antioxidants to normal ranges. The chemopreventive potential of saffron thus is likely due to antioxidant properties and modulating effects on detoxification in favour of the excretion of carcinogenic metabolites during DMBA-induced hamster buccal pouch carcinogenesis.
28 citations
TL;DR: Findings support that, despite some concentration effects, DMBA induces ovarian DNA damage and that DNA repair mechanisms are induced as a potential mechanism to prevent follicle loss.
21 citations
TL;DR: The effects of morin on the pharmacokinetics of etoposide in rats with 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumors was investigated, with significant differences between control and DMBA-WOM rats.
Abstract: Etoposide, used for the treatment of breast cancer, is mainly metabolized via hepatic cytochrome P450 (CYP) 3A4 in humans and is also a substrate for p-glycoprotein (P-gp). Morin is known to be able to modulate the activities of metabolic enzymes including CYPs and can act as a potent P-gp inhibitor. The purpose of this study was to investigate the effects of morin on the pharmacokinetics of etoposide in rats with 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumors. Etoposide was administered intravenously (2 mg/kg) and orally (10 mg/kg) in control and DMBA rats without (DMBA-WOM) and with (DMBA-WM) morin (15 mg/kg). Protein and mRNA expression of CYP3A and P-gp was analyzed, and the tissue distribution of etoposide was also measured. Both protein and mRNA expression of CYP3A and P-gp was inhibited by morin in the liver, intestine and breast tumors of DMBA-WM rats. After both intravenous and oral administration of etoposide in DMBA-WM rats, the total area under the plasma concentration-time curve from time zero to infinity (AUC) of etoposide was significantly greater, and the time-averaged total body clearance (CL) of etoposide was significantly slower than those in control and DMBA-WOM rats. The amount of etoposide recovered from each tissue was significantly higher in DMBA-WM rats, especially in the breast tumor, liver and large intestine. No significant differences between control and DMBA-WOM rats were observed. Taken together, greater AUC and slower CL of etoposide in DMBA-WM rats could possibly be due to the inhibition of hepatic CYP3A (intravenous) and mainly due to the inhibition of intestinal CYP3A and P-gp (oral) by morin.
20 citations
TL;DR: Results suggest that fermented Maesil has the ability to suppress the development of DMBA-TPA induced skin carcinogenesis, via the reduction of lipid peroxidation, enhancing total antioxidant capacity and phase II detoxifying enzyme.
Abstract: Maesil (Prunus mume Siebold and Zucc.), a member of the genus Rosaceae, has been reported to have antioxidative effects, as well as anticancer influence in many cancer lines. Thus, this present study was designed to investigate the inhibitory effect of fermented Maesil with probiotics against 7,12-dimethylbenz[a]anthracene (DMBA), 12-O-tetradecanoyl phorbol 13-acetate (TPA)-induced mouse skin carcinogenesis via its antioxidative potential. Mice were fed a diet containing fermented Maesil, containing either 1% (1% FM fed group) or 2% (2% FM fed group) along with probiotics following DMBA and TPA exposure. Continuous ingestion of the experimental feed markedly inhibited skin carcinogenesis, as evidenced by a marked decrease in papilloma numbers and epidermal hyperplasia as well as cellular proliferation and the percentage of proliferating-cell nuclear antigen positive cells. Also, the FM fed group showed an increase of total antioxidant capacity as well as an increased level of phase II detoxifying enzymes such as superoxide dismutase, concurrent with a decreased lipid peroxidation activity level. Taken together, these results suggest that fermented Maesil has the ability to suppress the development of DMBA-TPA induced skin carcinogenesis, via the reduction of lipid peroxidation, enhancing total antioxidant capacity and phase II detoxifying enzyme.
19 citations
TL;DR: The present data strongly suggest that anticancer potentiality of (+)-catechin-rich AQCE may be attributable to its ability to positively modulate tumor markers as well as the antioxidant system that could decompose the peroxides and, thereby, offer a protection against lipid peroxidation.
Abstract: Objective. The chemopreventive potential of (+)-catechin-rich extract of Acacia catechu (L.f.) Willd. heartwood (AQCE) was evaluated against human breast adenocarcinoma cell line (MCF-7) and 7,12-dimethylbenz[a]anthracene (DMBA)–induced mammary carcinoma in Balb/c mice. Methods. Cell cytotoxicity was investigated using different colorimetric assays. Apoptosis was observed using diphenylamine assay and fluorescent microscopy. AQCE was further evaluated for antitumor activity against DMBA-induced mammary carcinoma. The levels of tumor markers and oxidative stress were measured. Furthermore, level of transcription factors was measured by enzyme-linked immunosorbent assay. Results. The results showed that administration of AQCE showed a dose-dependent growth inhibition response and DNA fragmentation in MCF-7 cells. Tumor multiplicity was significantly decreased to 42.91% with AQCE when compared with DMBA-treated animals. The levels of tumor markers such as total sialic acid and lipid-associated sialic acid we...
17 citations
TL;DR: The therapeutic property of D-Pinitol might be due to its strong antioxidant and remarkable induction in phase II and significant modulation in phase I drug metabolizing enzymes and prominent influence in the proteins of apoptotic, anti-apoptotic and tumor suppressors which ultimately end up with the consideration in the treatment of genotoxin mediated carcinogenesis.
17 citations
TL;DR: Results showed that 0.1% dietary apigenin reduced MPA-dependent tumor incidence; however, the same dietary level increased tumor multiplicity in animals that developed tumors, suggesting that route of administration may influence its action.
Abstract: Medroxyprogesterone acetate (MPA) is a synthetic progestin commonly administered to postmenopausal women for hormone replacement therapy and has been associated with increased risk of breast cancer. MPA has been shown to accelerate the development of mammary tumors in a 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer animal model. Previously, we have shown that intraperitoneally administered apigenin effectively treated and prevented the progression of MPA-accelerated breast cancer in DMBA-induced and xenograft mammary cancer models. Here we used the DMBA model to examine the chemopreventive effect of dietary apigenin against MPA-accelerated tumors with 3 different levels of apigenin (0.02%, 0.1%, and 0.5% w/w) incorporated into a phytoestrogen-free diet. Results showed that 0.1% dietary apigenin reduced MPA-dependent tumor incidence; however, the same dietary level increased tumor multiplicity in animals that developed tumors. Neither 0.02% nor 0.5% dietary apigenin reduced MPA-dependent tumo...
16 citations
TL;DR: Oral administration of GLEet on tumor bearing animals significantly diminished the levels of lipid peroxidation thereby enhancing the nonenzymatic antioxidants and also positively regulated the estrogen receptor hormones level to near normal when compared with DMBA treated rats, suggesting that G. lucidum may be efficiently used as a chemopreventive agent against mammary carcinogenesis.
Abstract: Background: Mushrooms are an important natural source represents a major and untapped potent pharmaceutical product. Ganoderma lucidum (G. lucidum) an important medicinal mushroom has been shown to contain high amount of antioxidant. However, in vivo studies on G. lucidum fruiting bodies are lacking. Objectives: To determine the effects of G. lucidum fruiting bodies ethanolic extract (GLEet) on expression of xenobiotic enzymes, oxidant-antioxidant and hormonal status on 7,12-dimethyl benz[a]antheracene (DMBA) induced experimental breast cancer was investigated in female Sprague dawley rats. Materials and Methods: Cancer bearing female Sprague dawley rats was orally treated with GLEet (500mg/kg body weight) for 16 weeks. Incidence and tumor volume in each groups, and biochemical parameters were carried out in plasma, liver, and mammary tissues of animals. Histopathological and immunohistochemical analysis were also determined. Result: Oral administration of GLEet on tumor bearing animals significantly diminished the levels of lipid peroxidation thereby enhancing the nonenzymatic antioxidants and also positively regulated the estrogen receptor hormones level to near normal when compared with DMBA treated rats. Moreover, it also positively modulates the xenobiotic metabolizing enzymes. Therefore, the dietary administration of G. lucidum may be efficiently used as a chemopreventive agent against mammary carcinogenesis. Conclusion: We concluded that G. lucidum is a potent chemopreventive agent, thereby it offers maximum protection against DMBA-induced mammary carcinogenesis.
01 Jan 2013
TL;DR: The present work was conducted to study the protective effect of ginger extract (GE) against the hepatotoxicity induced by 7, 12-dimethylbenz(a)anthracene (DMBA) in female rats, and showed a highly significant decrease in body weight and an improvement in the hepatic lesions induced by DMBA.
Abstract: The present work was conducted to study the protective effect of ginger extract (GE) against the hepatotoxicity induced by 7, 12-dimethylbenz(a)anthracene (DMBA) in female rats. DMBA treated group showed a highly significant decrease in body weight. However, DMBA+GE treated group displayed a highly significant increase in body weight compared with DMBA treated group. Histologically, the liver of DMBA treated group showed nodule-like structures, hepatic cirrhosis, congestion of blood vessels, intercellular hemorrhage, hepatic pyknotic nuclei, lymphocytic infiltration, dilation of blood sinusoids and large amount of collagen fibres. DMBA+GE treated group displayed an improvement in the hepatic lesions induced by DMBA. Histochemically, the liver sections of DMBA treated group showed a marked depletion of polysaccharides and total protein content. However, DMBA+GE treated group showed a moderate increase in liver polysaccharides and total protein contents. Immunohistochemically, the hepatocytes of DMBA treated group showed a highly significant increase in the PCNA labelling index. However, DMBA+GE treated group displayed a highly significant decrease in the PCNA labelling index when compared with DMBA treated group.
Journal Article•
TL;DR: The findings confirm that inducing ovarian tumors in mice by chemical means is an effective method for studying early stages of tumor development that may be relevant to epithelial ovarian cancers that arise in postmenopausal women.
Abstract: Ovarian cancer has a high mortality rate because there are few symptoms in early disease development. The incidence of ovarian cancer increases in women after menopause. Understanding early events in this disease can best be achieved by using animal models. Therefore, the objective of this study was to develop and track the onset of ovarian tumorigenesis in mice mimicking characteristics of postmenopausal epithelial cancer in women. Female B6C3F1 mice (age, 28 d) received 4-vinylcyclohexene diepoxide (VCD, 160 mg/kg IV daily for 20 d) to cause ovarian failure. Four months after VCD treatment, via surgical intervention, each mouse received a single injection of 7,12-dimethylbenz[a]anthracene (DMBA) or vehicle control (sesame oil) under the bursa of the right ovary to cause ovarian neoplasms. The experimental groups were untreated controls (Con–Con), DMBA-treatment only (Con–DMBA), VCD treatment only (VCD–Con), and VCD+DMBA-treated (VCD+DMBA) mice. At 3, 5, 7, and 9 mo after DMBA injection, ovaries were collected for histologic and immunohistochemical evaluation. No tumors developed in Con–Con mice. All VCD-treated mice (with or without DMBA) exhibited ovarian failure. Mice that received both VCD and DMBA exhibited tumors at 3 mo (50%), 5 mo (14%), 7 mo (90%), and 9 mo (57%) after DMBA treatment; 31% of the tumors were epithelial in origin. Our findings confirm that inducing ovarian tumors in mice by chemical means is an effective method for studying early stages of tumor development that may be relevant to epithelial ovarian cancers that arise in postmenopausal women.
TL;DR: The results of the present study suggest that andrographolide suppressed tumor formation in the buccal mucosa of hamsters treated with DMBA through its anti-cell proliferative and anti-angiogenic potential.
Abstract: Our aim was to explore anti-cell proliferative and anti-angiogenic potential of andrographolide by analyzing the expression pattern of cell proliferative (PCNA, Cyclin D1) and angiogenic (VEGF) markers during 7, 12-dimethylbenz(a)anthracene (DMBA) induced hamster buccal pouch carcinogenesis. DMBA painting three times a week for 14 weeks in the buccal pouch of golden Syrian hamsters resulted in oral tumors which were histopathologically diagnosed as well differentiated squamous cell carcinoma. Immunohistochemical (PCNA, VEGF) and RT-PCR (Cyclin D1) studies revealed over expression of PCNA, VEGF and Cyclin D1 in the buccal mucosa of hamsters treated with DMBA alone. Oral administration of andrographolide at a dose of 50 mg/kg bw to hamsters treated with DMBA not only suppressed the histological abnormalities but also down regulated the expression of PCNA, VEGF and Cyclin D1. The results of the present study suggest that andrographolide suppressed tumor formation in the buccal mucosa of hamsters treated with DMBA through its anti-cell proliferative and anti-angiogenic potential.
TL;DR: Under in vivo conditions, BB reduced the frequencies of MNNG- and DMBA-induced MN in PCEs, but in the case of the protective effect of BB against DMBA a dramatic reduction in the percentage of PCEs was observed, suggesting increased cytotoxicity.
Abstract: The protective effect of blueberry (BB) on the clastogenic effects of MNNG and DMBA was evaluated with the induced micronucleus (MN) frequency as a biomarker, both in vitro and in vivo. Human hepatoma HepG2 cells, which contain most of the metabolic activating enzymes was used for the in vitro test. MN frequencies were determined in binucleated cells generated by blocking cytokinesis by use of cytochalasin-B. The MN frequency in vivo was determined in polychromatic erythrocytes (PCEs) from the bone marrow of treated mice. BB by itself was not toxic both in vivo and in vitro. There was no evidence of a potential physico-chemical interaction between BB and the test carcinogens in vitro. Pre-treatment with BB reduced the MN frequency induced by MNNG. But, simultaneous treatment and post-treatment with BB did not affect the frequency of MNNG-induced MN. BB did not affect the frequency of DMBA-induced MN in vitro under any test condition. Under in vivo conditions, BB reduced the frequencies of MNNG- and DMBA-induced MN in PCEs, but in the case of the protective effect of BB against DMBA a dramatic reduction in the percentage of PCEs was observed, suggesting increased cytotoxicity.
TL;DR: Hyperleptinemia was suggested to contribute to tumor growth as well as to susceptibility to tumorigenesis and more aggressive phenotypes in Zucker lean rats.
Abstract: Susceptibility to 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis was investigated in lean Zucker (+/fa) rats carrying one mutated leptin receptor gene and wild-type controls (+/+). Rats with both genotypes were given a single DMBA administration and divided into two groups, one group was fed on basal diet mixed with 10% corn oil and the other was fed on basal diet alone. The minimum latency period of palpable carcinomas in +/fa rats of both groups was 8 weeks following DMBA treatment, in contrast to the 11-12 weeks in +/+. The incidence and multiplicity of carcinomas increased or showed a tendency for increase in the early stages in +/fa rats of both groups as compared to the +/+ counterparts. The volumes of carcinomas showed a tendency to increase in the corn oil diet groups of both genotypes. The major histopathological phenotype of carcinomas in all groups was well-differentiated without distinct atypia (multiplicity, 0.69-1.09/rat), but moderately/poorly differentiated carcinomas with atypia were also found, predominantly in +/fa rats (0.09-0.21). These latter tumors were characterized by elevated ERK activity but not estrogen receptor expression. Serum leptin concentrations in +/fa rats at 7 weeks of age were higher than those in +/+ and were elevated by the corn oil diet; however, no obvious change was detected in other serum parameters examined. In conclusion, +/fa rats proved more susceptible to DMBA-induced mammary carcinogenesis than +/+ controls, and hyperleptinemia was suggested to contribute to tumor growth as well as to susceptibility to tumorigenesis and more aggressive phenotypes in Zucker lean rats.
01 Jan 2013
TL;DR: From the present study, it can be inferred that Syzygium cumini possesses has chemopreventive and anti-oxidative potential for chemical induced carcinogenesis and may be linked with the antioxidant/free radical-scavenging constituents present in the extract.
Abstract: Investigation of cancer chemopreventive and anti-oxidative property of S.cumini seed extract (SCE) on 7,12-dimethyl benz(a)anthracene (DMBA) induced skin carcinogenesis in mice. Animals were divided into four groups on the basis of their respective treatments wherein mice of Group I & II served as vehicle treated and SCE treated controls respectively. For induction of skin tumors, mice of Group III and IV were applied topically with 7,12-dimethylbenz(a)anthracene (DMBA) 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). Mice of Group IV were administered S.cumini seed extract (SCE) at peri- & post-initiational stage. The results of the study revealed a significant decrease in incidence, cumulative number of papillomas, tumor yield and tumor burden in mice of Group IV as compared with DMBA alone at the end of experiment. A significant reduction in tumor weight and tumor volume was also observed. Reduction in the incidence and number of papilloma, the preneoplastic lesions, was considered to be the mean of assessment. Significant (p<0.01) decrease in the level of lipid peroxidation and significant (p<0.01-p<0.001) enhancement in the activity of antioxidants (GSH, SOD, Vitamin-C) and total proteins levels were recorded in Group IV. SCE was also found potential in reducing the histopathological lesions induced in tumors by DMBA. From the present study, it can be inferred that Syzygium cumini possesses has chemopreventive and anti-oxidative potential for chemical induced carcinogenesis. Such chemopreventive activity may be linked with the antioxidant/free radical-scavenging constituents present in the extract.
TL;DR: The ErbB expression is different according to their histological condition, suggesting differential participation of the erbB family in oral carcinogenesis induced by alcohol and DMBA.
Abstract: Objetive: The aim of this study was to determine erbB expression in normal mucosa, oral dysplasia, and invasive carcinomas developed in the hamster’s buccal pouch chemical carcinogenesis model. Study design: Fifty Syrian golden hamsters were equally divided in five groups (A-E); two controls and three experimental group exposed to alcohol, DMBA, or both for 14 weeks. Number of tumors per cheek, volume, histological condition, erbB expression were determined and results were analyzed by the Mann–Whitney U and Dunn’s test. Results: Control groups and those exposed to alcohol (A, B and C respectively) only presented clinical and histological normal mucosa; while those exposed to DMBA or DMBA plus alcohol (D and E groups) developed dysplasia and invasive carcinomas. erbB2, erbB3, and erbB4 increased their expression in alcohol-exposed mucosa, dysplasia, and invasive carcinomas. We observed a similar expression level for erbB2 in dysplasia and carcinomas; while, erbB3 and erbB4 were similar only in carcinomas. Conclusion: The DMBA and alcohol can be considered as carcinogen and promoter for oral carcinogenesis. The erbB expression is different according to their histological condition, suggesting differential participation of the erbB family in oral carcinogenesis induced by alcohol and DMBA.
Key words:erbB, 7,12- dimethylbenz(a)anthracene, oral squamous cell carcinoma.
01 Jan 2013
TL;DR: The efficacy of C. molmol in preventing mammary tumorigenesis was assessed by comparing its pretreatment effects in the DMBA-induced rat mammary carcinogenesis model to pretreatment with melatonin.
Abstract: 2 Abstract: Commiphora molmol is one of the most common herbs consumed in the Arabian countries. In this study the efficacy of C. molmol in preventing mammary tumorigenesis was assessed by comparing its pretreatment effects in the DMBA-induced rat mammary carcinogenesis model to pretreatment with melatonin. Virgin female Sprague-Dawley rats (5-6 weeks-old) were randomly divided into one of five groups: (1) melatonin (10 mg/ kg.b.wt; n=20); (2) Oleo-gum-resin of C. molmol (500mg/ Kg.bwt; n=20); (3) 0.5% ethanolic phosphate- buffered saline (PBS; n=20); (4) distilled water (n=20); (5) no treatment (n=10). All treatments started 15 days prior to DMBA and ended at the same day of DMBA administration. 1 - 4 groups received a single oral dose st th
TL;DR: The present data showed that the organoselenium compounds may have important effects in the maintainance of homeostasis against stress induced by DMBA.
Abstract: Objective:The aim of this study was to evaluate the chemopreventive potential of organoselenium compounds (Se I and Se II) in the well-established rat model treated with 7,12-dimethylbenz[a]anthracene (DMBA), by monitoring the extent of tyrosine hydroxylase (TH) activity, adrenomedullin (ADM) level and total RNA level in adrenal medulla. Organic pollutants are the most important environmental factor for the biologic systems. DMBA exposure appears to be associated with a number of physiological disease processes.Methods:The effects of Se I and Se II compounds were investigated on TH activity, ADM and total RNA levels in adrenal medulla of rats exposed to DMBA.Results:TH activity, ADM and total RNA levels were found to be increased significantly due to the effect of DMBA (p < 0.05). This increase was restricted in the Se I- and Se II-treated groups (p < 0.05).Conclusion:The present data showed that the organoselenium compounds may have important effects in the maintainance of homeostasis against stress indu...
TL;DR: Outcome of the present study revealed that diosgenin has potent anticlastogenic effects on DMBA treated hamsters.
Abstract: The present investigation explores the anticlastogenic effect of diosgenin on 7,12-dimethylbenz(a)anthracene (DMBA) treated clastogenesis. The frequency of bone marrow micronucleated polychromatic erythrocytes (MnPCEs), chromosomal aberrations (CA), deoxyribonucleic acid (DNA) damage as cytogenetic markers and the levels of lipid peroxidation by-products, activities of enzymatic antioxidant and the status of detoxification agents were performed to assess the anticlastogenic effects of diosgenin on DMBA treated hamsters. Intraperitoneal injection of DMBA (30 mg/kg bw) leads to clastogenesis in hamster. Elevated MnPCEs frequencies, CA, DNA damage, enhanced lipid peroxidation by products, declined antioxidant activities and detoxification cascade were observed in DMBA treated hamsters. Oral pretreatment with diosgenin (80 mg/kg bw) daily for a period of five days significantly reduced the frequency of MnPCEs, CA, DNA damage and normalized the levels of lipid peroxidation by products with increased activities...
Journal Article•
TL;DR: In this paper, the dose response effect of free ellagic acid (EA) and EANP against DMBA induced oxidative stress on hamster buccal pouch model was evaluated.
Abstract: Ellagic acid, a phenolic phytonutrient has become a focus of intense research owing to its role in prevention and treatment of cancer. In the present study, we proposed to screen the dose response effect of free ellagic acid (EA) and ellagic acid encapsulated nanoparticles (EANP) against DMBA induced oxidative stress on hamster buccal pouch model. DMBA (0.5% in mineral oil) was topically applied to the left buccal pouch of male Syrian hamsters 3 times a week for 14 weeks. Treatment groups received EA (20, 40, 80 mg/kg bw) and EANP (10, 20, 40 mg/kg bw) via oral gavage 3 times a week from 10 to 21 weeks. Animals were sacrificed at the end of the experimental period and free radical mediated oxidative damage was estimated using various biochemical markers such as lipid peroxidation and antioxidants (GSH, SOD, CAT & GPx) which are the key indicators for cancer risk at the precancerous stage. DMBA induced positive controls showed altered levels of lipid peroxidation which is associated with diminished cellular antioxidant status. Treatment with EA and EANP significantly augmented the activities of cellular antitoxidants and ultimately diminished the levels of lipid peroxidation which point towards suppression of preneoplastic lesions thereby reduces the cancerous risk. Thus from the aforementioned results it is showed that treatment with EA at the dose of 40 mg/kg bw and EANP at the dose of 20 mg/kg bw was found to be the optimal dose which proved antioxidant activity against DMBA induced oxidative stress on hamster buccal pouch carcinogenesis. Normal 0 false false false EN-US X-NONE X-NONE
01 Jan 2013
TL;DR: For example, this paper found that the lungs and macrophages released the majority of the ethyl acetate-soluble metabolite that they produced into the surrounding medium.
Abstract: Cultured mouse macrophages and trachea! and lung tissue each produced the same ethyl acetate-soluble derivatives of 7,12-dimethylbenz(a)anthracene (DMBA). The derivatives produced in the different cultures were indistinguishable by thin-layer chromatography and by high-pressure liquid chromatography but differed in their relative proportions. The greatest difference was seen between lungs and macrophages. The predominant me tabolite produced by lungs was 8,9-dihydro-8,9-dihydroxy7,12-dimethylbenz(a)anthracene, while macrophages pro duced equal quantities of both 8,9-dihydro-8,9-dihydroxy7,12-dimethylbenz(a)anthracene and a second uncharacterized derivative, Metabolite B, at low DMBA doses (0.05 /jg/ml medium) and primarily Metabolite B at higher DMBA doses (0.05 jug/ml medium). Macrophages released the majority of the ethyl acetate-soluble metab olites that they produced into the surrounding medium. With the exception of 8,9-dihydro-8,9-dihydroxy-7,12-dimethylbenz(a)anthracene, these derivatives were accu mulated within trachea! and luTig tissue when these or gans were cocultivated with macrophages in the presence of DMBA.
01 Jan 2013
TL;DR: In this article, the authors show that the isolated saponin (SM) attenuates DMBA induced renal carcino- genesis in mice, which is achieved by TLC and HPLC and characterization was done using IR and 1 H NMR.
Abstract: Present investigation shows that hydroethanolic extract of Moringa oleifera (MOHE) and its isolated saponin (SM) attenuates DMBA induced renal carcino- genesis in mice. Isolation of SM was achieved by TLC and HPLC and characterization was done using IR and 1 H NMR. Animals were pre-treated with MOHE (200 and 400 mg/kg body weight; p.o), BHA as a standard (0.5 and 1 %) and SM (50 mg/kg body weight) for 21 days prior to the administration of single dose of DMBA (15 mg/kg body weight). Administration of DMBA significantly (p \ 0.001) enhanced level of xenobiotic enzymes. It enhanced renal malondialdehyde, with reduction in renal glutathione content, antioxidant enzymes and glutathione- S-transferase. The status of renal aspartate transaminase, alanine transaminase, alkaline phosphatase and total pro- tein content were also found to be decreased along with increase in total cholesterol in DMBA administered mice. Pretreatment with MOHE and SM significantly reversed the DMBA induced alterations in the tissue and effectively suppressed renal oxidative stress and toxicity.