Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 34
Filter
Add more filters










Publication year range
1.
Bioinformation ; 16(11): 965-973, 2020.
Article in English | MEDLINE | ID: mdl-34803274

ABSTRACT

Astaxanthin (AXN) is known to have health benefits by epidemiological studies. Therefore, it is of interest to assess the effect of AXN (derived from indigenous unicellular green alga Haematococcus lacustris) to modulate cell cycle arrest, lysosomal acidification and eventually apoptosis using in vitro in A549 lung cancer cells. Natural extracts of astaxanthin were obtained by standardized methods as reported earlier and characterized by standard HPLC and MS. Treatment of A549 cells with AXN (purified fraction) showed significant reduction in cell viability (about 50%) as compared to crude extract at 50µM concentration. Thus, we show the anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris for further consideration. Together, our results demonstrated the anticancer potential of AXN from Haematococcus lacustris, which is found to be mediated via its ability to induce cell cycle arrest, lysosomal acidification and apoptotic induction.

3.
Gulf J Oncolog ; (4): 19-26, 2008 Jul.
Article in English | MEDLINE | ID: mdl-20084771

ABSTRACT

Treatment of acute myeloid leukemia (AML) in the elderly has always been a challenging task. Acute myeloid leukemia in older adults is a biologically and clinically distinct entity. Based on analysis of cytogenetic and molecular data, it is known that leukemic cells in older patients are intrinsically resistant to standard chemotherapy. Due to comorbid disease and impaired bone marrow stem cell reserve, older adults tolerate myelosuppressive chemotherapy poorly, with a treatment-related mortality rate of 25%. In spite of various available targeted therapies, the overall survival has not improved dramatically in the past decade. The ideal post remission regimen in this population has always been a matter of debate. Standard allogeneic bone marrow transplantation is too dangerous to be considered as a mean to eradicate minimal residual disease after remission is obtained and myelointensive chemotherapy is not a beneficial post-remission strategy in this age cohort. These disappointing results call for more effective and less toxic therapeutic options. The advent of non-myeloablative regimens has shown some prospects in select group of patients with good performance status. This review focuses on current therapeutic options available in this group of patients.


Subject(s)
Leukemia, Myeloid, Acute/drug therapy , Aged , Antineoplastic Agents/therapeutic use , Clinical Trials as Topic , Humans
4.
Breast Cancer Res Treat ; 66(2): 147-57, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11437101

ABSTRACT

Diindolylmethane (DIM) is formed by acid catalyzed dimerization of the phytochemical indole-3-carbinol, and both compounds inhibit formation and/or growth of mammary tumors in rodents. In this study, we have investigated the aryl hydrocarbon receptor (AhR) agonist activity and inhibitory AhR-estrogen receptor crosstalk induced by the following methyl-substituted DIMs: 1,1'-dimethyl-, 2,2'-dimethyl-, 5,5'-dimethyl-, 6,6'-dimethyl-, and 7,7'-dimethylDIM and 1,1',2,2'-tetramethylDIM. The six compounds bound to the rat cytosolic AhR in a transformation assay but, at concentrations < or = 10 microM, exhibited minimal to non-detectable AhR agonist or antagonist activities associated with CYP1A1 induction. In contrast, the methyl-substituted DIMs inhibited estrogen-induced T47D human breast cancer cell growth and the four most active compounds (1,1'-, 2,2'-, 5,5'-dimethylDIM and 1,1',2,2'-tetramethylDIM) inhibited one or more estrogen-induced responses in the 21-day-old female B6C3F1 mice at a dose of 100 mg/kg/day (X3). Induction of hepatic CYP1A1-dependent activity was not observed at this high dose. The antitumorigenic activity of these compounds was examined in 7,12-dimethylbenz[a]anthracene-induced rat mammary tumor model in which the DIM analogs were orally administered (by gavage in corn oil) at a dose of 1 mg/kg/day (X10). 1,1'-DimethylDIM, 5,5'-dimethylDIM and 1,1',2,2'-tetramethylDIM significantly inhibited mammary tumor growth, and this was not accompanied by changes in organ/body weights or histopathology. These studies demonstrate that methyl-substituted DIMs are selective AhR modulators (SAhRMs) with potential for clinical treatment of breast cancer.


Subject(s)
Anticarcinogenic Agents/pharmacology , Breast Neoplasms/pathology , Cell Division/drug effects , Indoles/pharmacology , Mammary Neoplasms, Experimental/pathology , Receptors, Aryl Hydrocarbon/antagonists & inhibitors , Animals , Anticarcinogenic Agents/chemistry , Female , Humans , Indoles/chemistry , Mice , Mice, Inbred Strains , Rats , Rats, Sprague-Dawley , Receptors, Estrogen/metabolism , Species Specificity , Tumor Cells, Cultured/drug effects , Uterus/drug effects
6.
Mol Cell Endocrinol ; 162(1-2): 211-20, 2000 Apr 25.
Article in English | MEDLINE | ID: mdl-10854714

ABSTRACT

Differences in ligand-activation of estrogen receptor alpha (ER(alpha)) were investigated in human HepG2 liver carcinoma and U2 osteogenic sarcoma cells transfected with wild-type ER (ER-wt) and variants expressing only activation function 1 (ERAF1) or AF2 (ER-AF2). The estrogen-responsive C3-luc construct containing the complement C3 gene promoter linked to a bacterial luciferase reporter gene was used to determine ligand-induced wild-type or variant ER activation. The quality pattern of ER-dependent responses was similar in both cell lines for a series of weakly estrogenic hydroxy and dihydroxyaromatic compounds including p-octylphenol, p-nonylphenol, 2',4',6'-trichloro-4-biphenylol, 2',3',4', 5'-tetrachloro-4-biphenylol, bisphenol A and 2, 2'-bis(p-hydroxyphenyl)-1,1,1-trichloroethane. However, some significant quantitative differences in these compounds were also observed. The weakly estrogenic pesticide, kepone, and the phytoestrogens, resveratrol (a trihydroxystilbene) and naringen (a flavanone), induced distinctly different patterns of responses; induction by these compounds was not observed in either cell line cotransfected with ER-wt or ER-AF2. In contrast, naringen activated ER-AF1 in HepG2 cells and resveratrol activated ER-AF1 in U2 cells. In HepG2 cells cotreated with E2 plus the estrogenic compounds, only BPA and resveratrol exhibited ER(alpha) antagonist activity. Structure-dependent differences in ER(alpha) activation and inhibition are consistent with the increasingly complex patterns of ER action in various tissues and indicate that the estrogenic activity of an individual compound can only be determined by using an extensive testing protocol.


Subject(s)
Isoflavones , Liver Neoplasms/metabolism , Osteosarcoma/metabolism , Receptors, Estrogen/metabolism , Animals , Complement C3/genetics , Estrogen Receptor alpha , Estrogens, Non-Steroidal/metabolism , Female , Genes, Reporter , Genetic Variation , Humans , In Vitro Techniques , Kinetics , Ligands , Luciferases/genetics , Mice , Phytoestrogens , Plant Preparations , Promoter Regions, Genetic , Receptors, Estrogen/agonists , Receptors, Estrogen/genetics , Transfection , Tumor Cells, Cultured , Uterus/metabolism
7.
Cancer Lett ; 151(2): 169-79, 2000 Apr 14.
Article in English | MEDLINE | ID: mdl-10738111

ABSTRACT

90%) by the haloDIMs at concentrations of 5 or 10 microM, and only 4, 4'-dichloroDIM alone increased cell proliferation. With the exception of 5,5'-difluoroDIM, the remaining compounds also inhibited E2-induced growth of MCF-7 human breast cancer cells. DihaloDIMs (100 mg/kg/dayx3) were not estrogenic in the immature female B6C3F1 mouse uterus; however, in animals co-treated with E2 (0.02 microg/mouse), 5,5'-dichloro- and 6,6'-dichloroDIM inhibited uterine progesterone receptor (PR) binding and uterine peroxidase activity, whereas 5,5'-dichloro- and 5,5'-dichloro-2,2'-dimethylDIM inhibited only the latter response. The antitumorigenic activities of the dihaloDIMs were determined by their inhibition of carcinogen-induced mammary tumor growth in female Sprague-Dawley rats. 4,4'-Dichloro-, 5,5'-dibromo- and 6,6'-dichloroDIM, significantly inhibited mammary tumor growth at doses of 1 mg/kg every second day, and no significant changes in organ weights or liver and kidney histopathology were observed. These three compounds were more active than DIM in the same in vivo assay.


Subject(s)
Anticarcinogenic Agents/pharmacology , Carcinogens/toxicity , Estradiol/pharmacology , Indoles/pharmacology , Mammary Neoplasms, Animal/chemically induced , Mammary Neoplasms, Animal/pathology , Animals , Anticarcinogenic Agents/chemistry , Anticarcinogenic Agents/therapeutic use , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Carcinogens/antagonists & inhibitors , Cell Division/drug effects , Dose-Response Relationship, Drug , Estrogen Antagonists/chemistry , Estrogen Antagonists/pharmacology , Estrogen Antagonists/therapeutic use , Female , Halogens/metabolism , Humans , Indoles/chemistry , Indoles/therapeutic use , Mammary Neoplasms, Animal/drug therapy , Mice , Organ Size/drug effects , Peroxidase/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Progesterone/metabolism , Tumor Cells, Cultured , Uterus/drug effects , Uterus/enzymology , Uterus/growth & development , Uterus/metabolism
8.
Carcinogenesis ; 20(1): 115-23, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9934858

ABSTRACT

3,3',4,4'-Tetrachlorobiphenyl (tetraCB) binds to the aryl hydrocarbon receptor (AhR), and several reports have demonstrated that AhR agonists exhibit antiestrogenic and antitumorigenic activities in human breast cancer cells, the rodent uterus and breast. In contrast, a recent study showed that 3,3',4,4'-tetraCB bound the estrogen receptor (ER) and exhibited ER agonist activities, and we therefore have reinvestigated the estrogenic and antiestrogenic activities of 3,3',4,4'-tetraCB. Our results showed that 3,3',4,4'tetraCB and a structurally related analog, 3,3',4,4',5-pentaCB, did not bind the mouse uterine or human ER, did not induce proliferation of MCF-7 or T47D human breast cancer cells or induce reporter gene activity in cells transfected with E2-responsive constructs derived from the creatine kinase B (pCKB) or cathepsin D (pCD) gene promoters. Moreover, 3,3',4,4'-tetraCB and 3,3',4,4',5-pentaCB did not induce an increase in uterine wet weight, peroxidase activity or progesterone receptor binding in the 21-25-day-old female B6C3F1 mouse uterus. In contrast, both compounds inhibited 17beta-estradiol (E2)-induced cell proliferation and transactivation in MCF-7/T47D cells and uterine responses in B6C3F1 mice; surprisingly inhibition of E2-induced reporter gene activity was not observed in T47D cells transfected with pCKB, and this was observed as a cell-specific response with other AhR agonists. Additionally, 3,3',4,4'-tetraCB significantly inhibited mammary tumor growth in female Sprague-Dawley rats initiated with 7,12-dimethylbenzanthracene. Our results indicate that 3,3',4,4'-tetraCB does not exhibit ER agonist activity but exhibits a broad spectrum of antiestrogenic responses consistent with ligand-mediated AhR-ER crosstalk.


Subject(s)
Anticarcinogenic Agents/therapeutic use , Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/pathology , Estrogen Antagonists/therapeutic use , Estrogens , Mammary Glands, Animal/drug effects , Mammary Neoplasms, Experimental/prevention & control , Neoplasms, Hormone-Dependent/pathology , Polychlorinated Biphenyls/therapeutic use , Receptors, Estrogen/drug effects , Uterus/drug effects , 9,10-Dimethyl-1,2-benzanthracene , Animals , Anticarcinogenic Agents/pharmacology , Antineoplastic Agents, Hormonal/pharmacology , Binding, Competitive , Cell Division , Estradiol/metabolism , Estradiol/pharmacology , Estrogen Antagonists/pharmacology , Female , Gene Expression Regulation/drug effects , Genes, Reporter , Humans , Mice , Organ Size/drug effects , Peroxidases/metabolism , Polychlorinated Biphenyls/chemistry , Polychlorinated Biphenyls/pharmacology , Promegestone/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Progesterone/drug effects , Structure-Activity Relationship , Transfection , Tumor Cells, Cultured/drug effects , Uterus/anatomy & histology , Uterus/enzymology
9.
Environ Health Perspect ; 106 Suppl 6: 1347-51, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9860891

ABSTRACT

The human diet contains industrial-derived, endocrine-active chemicals and higher levels of naturally occurring compounds that modulate multiple endocrine pathways. Hazard and risk assessment of these mixtures is complicated by noadditive interactions between different endocrine-mediated responses. This study focused on estrogenic chemicals in the diet and compared the relative potencies or estrogen equivalents (EQs) of the daily consumption of xenoestrogenic organochlorine pesticides in food (2.44 micrograms/day) with the EQs in a single 200-ml glass of red cabernet wine. The reconstituted organochlorine mixture contained 1,1,1-trichloro-2-(p-chlorophenyl)-2-(o-chlorophenyl)ethane, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene, endosulfan-1, endosulfan-2, p,p'-methoxychlor, and toxaphene; the relative proportion of each chemical in the mixture resembled the composition reported in a recent U.S. Food and Drug Administration market basket survey. The following battery of in vitro 17 beta-estradiol (E2)-responsive bioassays were utilized in this study: competitive binding to mouse uterine estrogen receptor (ER); proliferation in T47D human breast cancer cells; luciferase (Luc) induction in human HepG2 cells transiently cotransfected with C3-Luc and the human ER, rat ER-alpha, or rat ER-beta; induction of chloramphenicol acetyltransferase (CAT) activity in MCF-7 human breast cancer cells transfected with E2-responsive cathepsin D-CAT or creatine kinase B-CAT plasmids. For these seven in vitro assays, the calculated EQs in extracts from 200 ml of red cabernet wine varied from 0.15 to 3.68 micrograms/day. In contrast, EQs for consumption of organochlorine pesticides (2.44 micrograms/day) varied from nondetectable to 1.24 ng/day. Based on results of the in vitro bioassays, organochlorine pesticides in food contribute minimally to dietary EQ intake.


Subject(s)
Estrogens/biosynthesis , Food Contamination/analysis , Hydrocarbons, Chlorinated , Insecticides/pharmacology , Pesticide Residues/pharmacology , Wine/analysis , Alcoholic Beverages/analysis , Animals , Chloramphenicol O-Acetyltransferase/biosynthesis , Diet , Enzyme Induction/drug effects , Estradiol/pharmacology , Female , Humans , Male , Mice , Mice, Inbred Strains , Tumor Cells, Cultured
10.
Toxicol Appl Pharmacol ; 147(1): 93-100, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9356311

ABSTRACT

The estrogenic activity of 2',4',6'-trichloro-4-biphenylol (HO-PCB3), 2',3',4',5'-tetrachloro-4-biphenylol (HO-PCB4), and an equimolar mixture of both compounds (HO-PCB3/HO-PCB4) was investigated in the 21-day-old B6C3F1 mouse uterus, MCF-7 and MDA-MB-231 human breast cancer cells, HepG2 cells, and in a yeast-based reporter gene assay. Treatment of the animals with 17beta-estradiol (E2) (0.02 microg/kg/day x3) resulted in increased uterine wet weight, peroxidase activity and progesterone receptor binding. Treatment with 18, 73, 183 or 366 micromol/kg (x3) doses of HO-PCB3, HO-PCB4, or HO-PCB3/HO-PCB4 (equimolar) caused a dose-dependent increase in estrogenic activity; a maximal-induced response was not observed at any dose and the activity of the mixture was additive. Binding of E2, HO-PCB3, HO-PCB4, and HO-PCB3/HO-PCB4 to the mouse uterine estrogen receptor (ER) was determined in a competitive binding assay using [3H]E2 as the radioligand. The IC50 values were 1.1 x 10(-8), 3.4 x 10(-6), 9.9 x 10(-7), and 4.25 x 10(-6) m, respectively. HO-PCB3 and HO-PCB4 maximally induced MCF-7 cell proliferation, rat creatine kinase, and human complement C3 (C3-LUC) reporter gene activity at concentrations of 10(-5) to 10(-6) m, and these compounds were 10(3) to 10(4) less potent than E2. The HO-PCB3/HO-PCB4 mixture was active at the high concentration (10(-5) m) and was additive for these responses. HO-PCB3 and HO-PCB4 also exhibited estrogenic activity in human HepG2 cells cotransfected with C3-LUC and an ER expression plasmid, and the estrogenic activity of the HO-PCB mixture was additive. Similar results were obtained in yeast transformed with the human ER and a double estrogen responsive element upstream of the beta-gal reporter gene. The effects of variable ER expression on the potential synergistic interactions of HO-PCB3/HO-PCB4 were investigated in HepG2 cells cotransfected with C3-LUC (405 ng/well) and variable amounts of ER expression plasmid (270, 27, 2.7, or 0.27 ng/well). The results show that as ER levels decreased, the magnitude of the induction response by E2, HO-PCB3, HO-PCB4, and HO-PCB3/HO-PCB4 also decreased. However, the activities of the HO-PCB mixture were additive at high and low levels of ER. Similar results were obtained in MDA-MB-231 cells cotransfected with C3-LUC and variable amounts of ER expression plasmid. The results of this study demonstrate that for several estrogen-responsive assays in the mouse uterus; MCF-7, HepG2, and MDA-MBA-231 human cancer cells; and a yeast based-reporter gene assay, both HO-PCB3 and HO-PCB4 exhibited estrogenic activity. The estrogenic activity of an equimolar mixture of these compounds was additive at high and low levels of ER expression.


Subject(s)
Polychlorinated Biphenyls/toxicity , Receptors, Estrogen/drug effects , Receptors, Progesterone/drug effects , Uterus/drug effects , Animals , Breast Neoplasms , Cell Division/drug effects , Dose-Response Relationship, Drug , Drug Synergism , Female , Gene Expression Regulation/drug effects , Gene Expression Regulation/genetics , Humans , Liver Neoplasms , Mice , Peroxidases/analysis , Polychlorinated Biphenyls/chemistry , Polychlorinated Biphenyls/metabolism , Receptors, Estrogen/genetics , Receptors, Estrogen/metabolism , Receptors, Progesterone/genetics , Receptors, Progesterone/metabolism , Saccharomyces cerevisiae/genetics , Transfection , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism , Uterus/metabolism
11.
Regul Toxicol Pharmacol ; 26(1 Pt 1): 52-8, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9339480

ABSTRACT

Industrial-derived endocrine disruptors or endocrine-active chemicals (EACs) have been identified and hypothesized to play a role in human disease. Most of the xeno-EACs which have been characterized bind to the estrogen receptor, aryl hydrocarbon receptor, or androgen receptor. Hazard and risk assessment of xeno-EACs is complicated by several factors which include the following: (i) humans are exposed to relatively high levels of natural EACs compared to xeno-EACs; (ii) very little information on the effects of metabolism, serum, and intracellular binding proteins on target cell uptake of EACs is known; (iii) humans are exposed to EAC mixtures and their interactive effects may be additive, antagonistic, or synergistic and also response- and tissue-specific; and (iv) individual EACs may be agonists/antagonists for more than one endocrine response pathway. Scientific-based hazard and risk assessment of both natural and xeno-EACs clearly requires more information on dietary intakes, target organ exposures, mechanisms of action, and interactive effects of mixtures.


Subject(s)
Endocrine System/metabolism , Environmental Exposure , Xenobiotics/toxicity , Animals , Binding Sites , Endocrine System/drug effects , Humans , Receptors, Androgen/drug effects , Receptors, Androgen/metabolism , Receptors, Aryl Hydrocarbon/drug effects , Receptors, Aryl Hydrocarbon/metabolism , Receptors, Estrogen/drug effects , Receptors, Estrogen/metabolism , Risk Assessment
12.
Toxicol Appl Pharmacol ; 145(1): 111-23, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9221830

ABSTRACT

The effects of structure on the estrogenicity and antiestrogenicity of hydroxylated polychlorinated biphenyls were investigated using the following estrogen-sensitive assays: competitive binding to the rat and mouse cytosolic estrogen receptor (ER); immature rat and mouse uterine wet weight, peroxidase and progesterone receptor (PR) levels; induction of luciferase activity in HeLa cells stably transfected with a Gal4:human ER chimera and a 17mer-regulated luciferase reporter gene; proliferation of MCF-7 human breast cancer cells; induction of chloramphenicol acetyl transferase (CAT) activity in MCF-7 cells transiently transfected with a full-length human ER expression plasmid and a plasmid containing an estrogen-responsive vitellogenin A2 promoter linked to a CAT reporter gene. The chemicals synthesized for this study contained a 4-hydroxy group in one ring, a 2- or 3-chloro substituent meta or ortho to the hydroxyl group, and variable substitution (2',3',4',5'-, 2',3',4',6'-, 2',3',5',6'-tetrachloro and 2',4',6'-trichloro) in the chlorophenyl ring. The compounds included: 2,2',3',4',5'- (A), 2,2',3',4',6'- (B), and 2,2',3',5',6'-pentachloro- (C); 2,2',4',6'-tetrachloro-4-biphenylol (D); 2',3,3',4',5'- (E), 2',3,3',4',6'- (F), and 2',3,3',5',6'-pentachloro (G); and 2',3,4',6'-tetrachloro-4-biphenylol (H). With the exception of 2',3,4',6'-tetrachloro-4-biphenylol (H), all of the compounds competitively bound to the mouse and rat ER with relative binding affinities [compared to 17beta-estradiol (E2)] varying from 1.4 x 10(-3) to 5.3 x 10(-5). The structure-ER binding relationships for the hydroxy-PCB congeners were different in the rat and mouse, and no dose-dependent estrogenic activities were observed in the mouse or rat uterus. Several hydroxy-PCB congeners exhibited antiestrogenic activity (primarily in the mouse uterus) and two compounds, 2,2',3',5',6- and 2,2',3',4',6'-pentachloro-4-biphenylol, inhibited E2-induced uterine wet weight, PR binding, and peroxidase activity in the mouse uterus. 2,2',3',4',5'- and 2,2',3',4',6'-Pentachloro-4-biphenylol induced CAT activity in MCF-7 cells transiently transfected with the Vit-CAT plasmid; the remaining congeners did not induce CAT activity but exhibited antiestrogenic activity in MCF-7 cells cotreated with 10(-9) E2 plus 10(-5) M hydroxy-PCBs. Complementary structure-estrogenicity relationships were observed utilizing the HeLa cell luciferase induction and MCF-7 cell proliferation assays. The placement of the 2- or 3-chloro groups in the phenolic ring had minimal effects on estrogenic activity, whereas 2,4,6-trichloro- and 2,3,4,6-tetrachloro substitution in the chlorophenyl ring (B, D, F, and H) were required for this response. Substitution in the phenolic ring was also not important for structure-antiestrogenicity relationships, and the most active compounds (A, C, E, and G) contained 2',3',4',5'- and 2',3',5',6'-tetrachlorophenyl groups. Thus, structure-estrogenicity/antiestrogenicity relationships for this series of hydroxy-PCBs were complex and response-specific.


Subject(s)
Estrogen Antagonists/toxicity , Estrogens/toxicity , Polychlorinated Biphenyls/toxicity , Receptors, Estrogen/drug effects , Animals , Binding, Competitive , Breast Neoplasms/enzymology , Breast Neoplasms/pathology , Chloramphenicol O-Acetyltransferase/biosynthesis , Enzyme Induction/drug effects , Estrogen Antagonists/chemistry , Estrogen Antagonists/metabolism , Estrogens/chemistry , Estrogens/metabolism , Female , Gene Expression Regulation, Enzymologic/drug effects , HeLa Cells/cytology , HeLa Cells/drug effects , Humans , Luciferases/biosynthesis , Luciferases/genetics , Mice , Organ Size/drug effects , Peroxidases/metabolism , Polychlorinated Biphenyls/chemistry , Polychlorinated Biphenyls/metabolism , Rats , Receptors, Estrogen/metabolism , Receptors, Progesterone/drug effects , Receptors, Progesterone/metabolism , Recombinant Fusion Proteins/metabolism , Structure-Activity Relationship , Uterus/drug effects , Uterus/enzymology , Vitellogenins/genetics
13.
Endocrinology ; 138(4): 1520-7, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9075711

ABSTRACT

The estrogenic activity of dieldrin, toxaphene, and an equimolar mixture of both compounds (dieldrin/toxaphene) was investigated in the 21-day-old B6C3F1 mouse uterus, MCF-7 human breast cancer cells, and in yeast-based reporter gene assays. Treatment of the animals with 17beta-estradiol (E2) (0.0053 kg/day x3) resulted in a 3.1-, 4.8-, and 7.8-fold increase in uterine wet weight, peroxidase activity, and progesterone receptor binding, respectively. In contrast, treatment with 2.5, 15 and 60 micromol/kg (x3) doses of toxaphene, dieldrin, or dieldrin/toxaphene (equimolar) did not significantly induce a dose-dependent increase in any of the E2-induced responses. The organochlorine pesticides alone and the binary mixture did not bind to the mouse uterine estrogen receptor (ER) in a competitive binding assay using [3H]E2 as the radioligand. In parallel studies, estrogenic activities were determined in MCF-7 cells by using a cell proliferation assay and by determining induction of chloramphenicol acetyl transferase (CAT) activity in MCF-7 cells transiently transfected with plasmids containing estrogen-responsive 5'-promoter regions from the rat creatine kinase B and human cathepsin D genes. E2 caused a 24-fold increase in CAT activity in MCF-7 cells transiently transfected with creatine kinase B and a 3.8-fold increase in cells transiently transfected with the human cathepsin D construct. Treatment of MCF-7 cells with dieldrin, toxaphene, or an equimolar mixture of dieldrin plus toxaphene (10(-8)-10(-5) M) did not significantly induce cell proliferation or CAT activity in the transient transfection experiment with both plasmids. The relative competitive binding of the organochlorine pesticides was determined by incubating MCF-7 cells with 10(-9) M [3H]E2 in the presence or absence of 2 x 10(-7) M unlabeled E2 (to determine nonspecific binding), toxaphene (10(-5) M), dieldrin (10(-5) M), and equimolar concentrations of the dieldrin plus toxaphene mixture (10(-5) M). The binding observed for [3H]E2 in the whole cell extracts was displaced by unlabeled E2, whereas the organochlorine pesticides and binary mixture exhibited minimal to nondetectable competitive binding activity. E2 caused a 5000-fold induction of beta-galactosidase (beta-gal) activity in yeast transformed with the human ER and a double estrogen responsive element upstream of the beta-gal reporter gene. Treatment with 10(-6)-10(-4) M chlordane, dieldrin, toxaphene, or an equimolar mixture of dieldrin/toxaphene did not induce activity, whereas 10(-4) M endosulfan caused a 2000-fold increase in beta-gal activity. Diethylstilbestrol caused a 20-fold increase in activity in yeast transformed with the mouse ER and a single estrogen responsive element upstream of the beta-gal reporter gene. Dieldrin, chlordane, toxaphene, and endosulfan induced a 1.5- to 4-fold increase in activity at a concentration of 2.5 x 10(-5) M. Synergistic transactivation was not observed for any equimolar binary mixture of the pesticides at concentrations of either 2.5 x 10(-5) M or 2.5 x 10(-4) M. The results of this study demonstrate that for several estrogen-responsive assays in the mouse uterus, MCF-7 human breast cancer cells, and yeast-based reporter gene assays, the activities of both dieldrin and toxaphene were minimal, and no synergistic interactions were observed with a binary mixture of the two compounds.


Subject(s)
Dieldrin/pharmacology , Receptors, Estrogen/analysis , Toxaphene/pharmacology , Uterus/drug effects , Animals , Binding, Competitive , Breast Neoplasms/metabolism , Cell Division/drug effects , Dieldrin/administration & dosage , Drug Synergism , Estradiol/pharmacology , Female , Humans , Mice , Peroxidase/metabolism , Progesterone/metabolism , Rats , Toxaphene/administration & dosage , Transfection , Tumor Cells, Cultured , Uterus/metabolism
19.
J Assoc Physicians India ; 34(2): 157, 1986 Feb.
Article in English | MEDLINE | ID: mdl-3711012

ABSTRACT

PIP: The characteristics features of right-sided endocarditis are summarized in this case report of a 30-year-old female admitted with a history of high grade, continuous, fever, breathlessness, and dry cough over a 10-day period. The patient had had an incomplete abortion 15 days earlier for which dilatation and curettage was performed. On examination, the patient was toxic, febrile with a pulse of 118/minute and respiration 36/minute. Her blood pressure was 110/70 mm Hg. There was soft, tender hepatomegaly and soft splenomegely. There also were scattered coarse crepitations over both lungs. The vaginal examination revealed posterior fornicial bogginess and tenderness. Urine and cervical pus swab showed growth of klebsiella. The blood culture was negative. A plan chest X-ray revealed multiple, small, basal, pulmonary infiltrates. Posterior colopuncture revealed a small quantity of clear, yellowish fluid. Abdominopelvic ultrasonography revealed an ill-defined haziness in the parauterine region. The patient was treated with ampicillin, gentamycin, and metronidazole, but she continued to deteriorate. An urgent exploratory laparotomy was performed. The patient died on the 2nd postoperative day. The autopsy findings revealed that the heart was normal in size and shape. The tricuspid valve showed a large vegetation projecting into the ventricle. Microscopic examination revealed polymorphonuclear infiltration with clumps of gram-negative bacillifocal areas of myocarditis also were seen. In lungs the right lower lobe showed a small, hemorrhagic infarct. Both the liver and spleen were congested. Kidneys showed multiple petechiae on the external surface and on the cut section. Endocarditis during pregnancy may be because of perinatal infections, urinary tract infection, or septic thrombophlebitis of pelvi veins. Septic abortion of pelvic infection secondary to IUD also can provide portal of entry for bacteria. The common organisms are streptococcus, staphylococci, and occasionally bacteroides and gram negative bacilli. Clinical suspicion of right-sided endocarditis is justified in any patient with prolonged fever, cough, pleuritic pain, tachycardia, and multiple pulmonary infiltrates. Heart murmurs are usually absent and if present are soft and may be heard at atypical sites.^ieng


Subject(s)
Abortion, Septic/complications , Endocarditis, Bacterial/etiology , Tricuspid Valve , Adult , Female , Heart Valve Diseases/etiology , Humans , Klebsiella Infections/etiology , Pregnancy
SELECTION OF CITATIONS
SEARCH DETAIL
...