Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Database
Language
Publication year range
1.
Ecotoxicology ; 31(9): 1390-1402, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36223039

ABSTRACT

Heavy metal contamination in the coastal and marine ecosystems is becoming a serious risk to aquatic organisms and humans. This study reports the effects, including genetic damage, of accumulations of trace metals on Liza aurata, which is used as a bio-indicator species, in the Payas coast of Iskenderun Bay, north-eastern Mediterranean by COMET Assay. L. aurata were seasonally collected from a sampling site and a reference site for one year. Physicochemical parameters in water and trace metals in the tissues of fish collected from these sites were determined by electrochemical techniques. High DNA damage frequency in L. aurata was observed along the Payas coast of Iskenderun Bay compared to the reference site because of pollutants. The detected high levels of Cd, Pb, Fe and Cu accumulation in L. aurata exceed the maximum levels allowed by the national and international limit values. Significant positive correlations between Cd, Pb, Hg, Cr, Fe, Zn, and Cu accumulations and DNA damage parameters were observed in the present study. Additionally, we first reported the successful use of the electrochemical technique in the determination of trace metal concentrations in mullet. Moreover, L. aurata constitutes a key tool as a sentinel organism for biomonitoring of coastal ecosystems.


Subject(s)
Metals, Heavy , Perciformes , Smegmamorpha , Trace Elements , Water Pollutants, Chemical , Animals , Humans , Environmental Monitoring/methods , Bioaccumulation , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Ecosystem , Cadmium , Lead , Metals, Heavy/toxicity , DNA Damage
2.
Brain Res ; 1624: 479-488, 2015 Oct 22.
Article in English | MEDLINE | ID: mdl-26300221

ABSTRACT

Early adverse life experiences have been associated with anxiety-like behavior and memory impairment. N-methyl-d-aspartate receptors (NMDARs) play an important role in brain development. Enriched environments are known to positively influence emotional and cognitive functions in the brain. We examined the effects of maternal deprivation (MD) on NMDAR subunits in the hippocampus, locomotor activity, anxiety behaviors, and learning-memory performance of Balb/c mice. We also examined whether these effects could be reversed by raising the offspring in an enriched environment. The mice were separated from their mothers for a single 24h episode on postnatal day (PND) 9. The mice were weaned on day 21 and were housed under either standard (SE) or enriched (EE) environmental conditions. Emotional behaviors and cognitive processes of mice were evaluated using an open field (OF) test, an elevated plus maze (EPM) test, and a Morris water-maze (MWM). NMDAR subunits (GluN1, GluN2A, and GluN2B) mRNA expression levels in the hippocampus were examined by real-time PCR. In OF, MD had no effect on horizontal locomotor activity. MD increased anxiety-like behaviors in the EPM and decreased spatial learning performance in MWM; however, these effects were not reversed by EE. MD (in SE and EE conditions) increased GluN1, GluN2A, and GluN2B mRNA expressions in the hippocampus. In conclusion, MD led to the deterioration of the emotional and cognitive processes during adulthood. Moreover, environmental enrichment did not reverse the deleterious effects of the MD on emotional and cognitive functions and increased the NMDAR levels.


Subject(s)
Environment , Maternal Deprivation , Mood Disorders/etiology , Receptors, N-Methyl-D-Aspartate/metabolism , Animals , Animals, Newborn , Body Weight , Gene Expression Regulation/physiology , Hippocampus/metabolism , Maze Learning/physiology , Mice , Mice, Inbred BALB C , Mood Disorders/pathology , Psychomotor Performance , RNA, Messenger/metabolism , Receptors, N-Methyl-D-Aspartate/genetics
3.
Indian J Hum Genet ; 19(2): 196-201, 2013 Apr.
Article in English | MEDLINE | ID: mdl-24019622

ABSTRACT

OBJECTIVES: Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) is a newly defined disease in neuropsychiatry and occurs with an autoimmune mechanism after Group A Beta Hemolytic Streptococcus (GABHS) infection. Tumor necrosis factor (TNF), encoded by TNF-α gene has an important role in the apoptotic mechanisms of autoimmune diseases. Recently, TNF-α polymorphisms and autoimmune/psychiatric disorders have been reported to be related. In this regard, we focused on to investigate a possible relation between the TNF-α gene promoter region-308 G/A and - 850 C/T polymorphisms and PANDAS. MATERIALS AND METHODS: In this study, ages of PANDAS patient and control groups were ranging from 4 years to 12-year-old. Patient group includes childhood onset PANDAS patients (n = 42) and control group includes healthy children (n = 58). Diagnoses have been carried out according to Diagnostic and Statistical Manual of Mental Disorder (DSM-IV) criteria with Affective Disorders and Schizophrenia-Present and Lifetime (KSAD-S-PL) and Children Yale-Brown Obsessive Compulsive Scale Moreover, PANDAS criteria established by the American National Psychiatry Institute have been employed for diagnoses. For identifying polymorphisms; Polymerase Chain Reaction, Restriction Fragment Length Polymorphism and Polyacrylamid Gel Electrophoresis were used. RESULTS AND DISCUSSION: For -308 polymorphism, 37 of 42 PANDAS patients' results and for -850 C/T polymorphism, 38 of 42 PANDAS patients' results were obtained. According to our statistical analysis there is a positive relationship between PANDAS patients for -308 G/A polymorphism but not for -850 C/T polymorphism. There is no positive relationship between -308 G/A polymorphism and antistrep-tolysin O (ASO) titers and no relationship between -850 C/T polymorphism and ASO titers. We found, however, positive relationship between genders of patients (boys) and the disease. According to our results, we propose that the AA polymorphism of -308 G/A polymorphism can be used as a molecular indicator for PANDAS.

4.
Indian J Hum Genet ; 19(4): 408-11, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24497704

ABSTRACT

OBJECTIVES: Estrogen is one of the most crucial hormones participating in the proliferation and carcinogenesis of the prostate glands. Genetic polymorphisms in the estrogen metabolism pathway might be involved in the risk of prostate carcinoma development. We evaluated the association between genetic polymorphisms in estrogen receptor alpha (ESR1) and catechol-O-methyltransferase (COMT) genes and the risk of developing familial prostate carcinoma. MATERIALS AND METHODS: In this study, 34 cases with prostate carcinoma whose first-degree relatives had prostate carcinoma and 30 healthy age-matched male controls were enrolled. The genotypes of ESR1 and COMT genes were analyzed employing polymerase chain reaction-restriction fragment length polymorphism method. 34 cases with prostate carcinoma, whose first degree relatives had prostate carcinoma and 14 age-matched male controls were enrolled to analyze the genotype of these two genes. RESULTS: Among control patients, the ESR1 PvuII genotypes of C/C, C/T and T/T were observed in 37%, 26% and 37%, respectively, whereas the C/C, C/T and T/T genotypes were observed in 18%, 41% and 41% of case patients, respectively. Among controls, the ESR1 PvuII allele frequencies of C and T were equally observed, whereas the C and T allele frequencies were observed in 38% and 62% of patients, respectively. Among ESR1 PvuII genotypes there were not any significant difference in terms of genotype (P = 0.199) and allele (P = 0.181) frequencies. Among controls, the ESR1 XbaI genotypes of G/G, G/A and A/A were observed in 33%, 37% and 33%, respectively, whereas the G/G, G/A and A/A genotypes were observed in 12%, 47% and 41% of patients, respectively. Among controls, the ESR1 XbaI allele frequencies of A and G were observed equally, respectively, whereas the A and G frequencies were observed in 65% and 35% of patients, respectively. Among ESR1 Χ baI, there was not any significant difference in terms of genotype (P = 0.111) and allele (P = 0.093) frequencies. But the C/C genotype of the PvuII site and G/G genotype of the XbaI site in the ESR1 gene were associated significantly with the risk of developing prostate carcinoma. The G/G, G/A and A/A genotypes of the COMT gene were observed in 50%, 29% and 21% of control patients and in 53%, 21% and 26% of case patients, respectively. The A and G allele frequencies of the COMT gene were observed in 36.7%, 63.3% of control patients and in 36.8%, 63.2% of case patients, respectively. In COMT gene, there was not any significant difference in terms of genotype (P = 0.843) and allele (P = 0.991) frequencies. But the G/A genotype of the COMT gene had a weak tendency toward increased risk. CONCLUSION: Polymorphisms of ESR1 gene in the estrogen metabolism pathway were associated significantly with familial prostate carcinoma risk. Single nucleotide polymorphisms of low-penetrance genes are targets for understanding the genetic susceptibility of familial prostate carcinoma.

5.
N Engl J Med ; 366(7): 629-35, 2012 Feb 16.
Article in English | MEDLINE | ID: mdl-22335740

ABSTRACT

Gonadotropin-releasing hormone (GnRH) is the central regulator of gonadotropins, which stimulate gonadal function. Hypothalamic neurons that produce kisspeptin and neurokinin B stimulate GnRH release. Inactivating mutations in the genes encoding the human kisspeptin receptor (KISS1R, formerly called GPR54), neurokinin B (TAC3), and the neurokinin B receptor (TACR3) result in pubertal failure. However, human kisspeptin loss-of-function mutations have not been described, and contradictory findings have been reported in Kiss1-knockout mice. We describe an inactivating mutation in KISS1 in a large consanguineous family that results in failure of pubertal progression, indicating that functional kisspeptin is important for puberty and reproduction in humans. (Funded by the Scientific and Technological Research Council of Turkey [TÜBITAK] and others.).


Subject(s)
Hypogonadism/genetics , Kisspeptins/genetics , Mutation , Puberty/genetics , Adolescent , Adult , Child , Consanguinity , Female , Genes, Recessive , Genotyping Techniques , Gonadotropin-Releasing Hormone/metabolism , Humans , Male , Pedigree , Sequence Analysis, DNA
6.
J Mol Endocrinol ; 47(1): 69-80, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21628418

ABSTRACT

Aromatase catalyzes the conversion of C(19) steroids to estrogens. Aromatase and progesterone, both of which function at different steps of steroidogenesis, are crucial for the sexually dimorphic development of the fetal brain and the regulation of gonadotropin secretion and sexual interest in adults. The aromatase gene (Cyp19a1) is selectively expressed in distinct neurons of the mouse hypothalamus through a distal brain-specific promoter, I.f, located ∼40 kb upstream of the coding region. However, the regulation of aromatase expression in the brain is not well understood. In this study, we investigated a short feedback effect of progesterone analogues on aromatase mRNA expression and enzyme activity in estrogen receptor α (Esr1)-positive or -negative mouse embryonic hypothalamic neuronal cell lines that express aromatase via promoter I.f. In a hypothalamic neuronal cell line that highly expresses aromatase, progesterone receptor (Pgr), and Esr1, a progesterone agonist, R5020, inhibited aromatase mRNA level and enzyme activity. The inhibitory effect of R5020 was reversed by its antagonist, RU486. Deletion mutants of promoter I.f suggested that inhibition of aromatase expression by progesterone is conferred by the nt -1000/-500 region, and R5020 enhanced binding of Pgr to the nt -800/-600 region of promoter I.f. Small interfering RNA knockdown of Pgr eliminated progesterone-dependent inhibition of aromatase mRNA and enzyme activity. Taken together, progesterone enhances recruitment of Pgr to specific regions of the promoter I.f of Cyp19a1 and regulates aromatase expression in hypothalamic neurons.


Subject(s)
Aromatase/genetics , Neurons/metabolism , Receptors, Progesterone/metabolism , Animals , Aromatase/chemistry , Aromatase/metabolism , Base Sequence , Cell Line , Chromatin Immunoprecipitation , Enzyme Assays , Estrogen Receptor alpha/metabolism , Estrogens/pharmacology , Feedback, Physiological , Genes, Reporter , Hypothalamus/cytology , Hypothalamus/metabolism , Luciferases, Renilla/biosynthesis , Luciferases, Renilla/genetics , Mice , Mifepristone/pharmacology , Molecular Sequence Data , Progestins/pharmacology , Promegestone/pharmacology , Promoter Regions, Genetic , Receptors, Progesterone/agonists , Receptors, Progesterone/antagonists & inhibitors , Transcription, Genetic/drug effects
7.
Biol Reprod ; 81(5): 956-65, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19605792

ABSTRACT

Aromatase (CYP19A1) catalyzes the conversion of C(19) steroids to estrogens. Aromatase and its product estradiol (E(2)) are crucial for the sexually dimorphic development of the fetal brain and the regulation of gonadotropin secretion and sexual interest in adults. The regulation of aromatase expression in the brain is not well understood. The aromatase (Cyp19a1) gene is selectively expressed in distinct neurons of the hypothalamus through a distal brain-specific promoter I.f located approximately 36 kb upstream of the coding region. Here, we investigated a short feedback effect of E(2) on aromatase mRNA expression and enzyme activity using estrogen receptor alpha (ESR1; also known as ER alpha)-positive or ESR1-negative mouse embryonic hypothalamic neuronal cell lines that express aromatase via promoter I.f. Estradiol regulated aromatase mRNA expression and enzyme activity in a time- and dose-dependent manner, whereas an E(2) antagonist reversed these effects. The nucleotide -200/-1 region of promoter I.f conferred E(2) responsiveness. Two activator protein 1 (AP-1) elements in this region were essential for induction of promoter activity by E(2). ESR1 and JUN (c-Jun) bound to these AP-1 motifs in intact cells and under cell-free conditions. The addition of an ESR1 mutant that interacts with JUN but not directly with DNA enhanced E(2)-dependent promoter I.f activity. Independently, we demonstrated an interaction between ESR1 and JUN in hypothalamic cells. Knockdown of ESR1 abolished E(2)-induced aromatase mRNA and enzyme activity. Taken together, E(2) regulates Cyp19a1 expression via promoter I.f by enhanced binding of an ESR1/JUN complex to distinct AP-1 motifs in hypothalamic cells. We speculate that this mechanism may, in part, regulate gonadotropin secretion and sexual activity.


Subject(s)
Aromatase/metabolism , Estrogen Receptor alpha/metabolism , Hypothalamus/metabolism , Neurons/metabolism , Promoter Regions, Genetic/physiology , Analysis of Variance , Animals , Aromatase/genetics , Blotting, Western , Cell Line , Cells, Cultured , Chromatin Immunoprecipitation , Dose-Response Relationship, Drug , Electrophoretic Mobility Shift Assay , Enzyme Assays , Estradiol/analogs & derivatives , Estradiol/pharmacology , Estrogen Antagonists/pharmacology , Estrogens/pharmacology , Fulvestrant , Hypothalamus/cytology , Hypothalamus/drug effects , Mice , Neurons/cytology , Neurons/drug effects , Promoter Regions, Genetic/genetics , Proto-Oncogene Proteins c-fos/genetics , Proto-Oncogene Proteins c-fos/metabolism , Proto-Oncogene Proteins c-jun/genetics , Proto-Oncogene Proteins c-jun/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/pharmacology , Reverse Transcriptase Polymerase Chain Reaction , Time Factors , Transcription Factor AP-1/genetics , Transcription Factor AP-1/metabolism , Transfection
8.
J Clin Endocrinol Metab ; 94(2): 623-31, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19001523

ABSTRACT

CONTEXT: Products of at least five specific steroidogenic genes, including steroidogenic acute regulatory protein (StAR), which facilitates the entry of cytosolic cholesterol into the mitochondrion, side chain cleavage P450 enzyme, 3beta-hydroxysteroid-dehydrogenase-2, 17-hydroxylase/17-20-lyase, and aromatase, which catalyzes the final step, are necessary for the conversion of cholesterol to estrogen. Expression and biological activity of StAR and aromatase were previously demonstrated in endometriosis but not in normal endometrium. Prostaglandin E2 (PGE2) induces aromatase expression via the transcriptional factor steroidogenic factor-1 (SF1) in endometriosis, which is opposed by chicken-ovalbumin upstream-transcription factor (COUP-TF) and Wilms' tumor-1 (WT1) in endometrium. OBJECTIVE: The aim of the study was to demonstrate a complete steroidogenic pathway leading to estrogen biosynthesis in endometriotic cells and the transcriptional mechanisms that regulate basal and PGE2-stimulated estrogen production in endometriotic cells and endometrium. RESULTS: Compared with normal endometrial tissues, mRNA levels of StAR, side chain cleavage P450, 3beta-hydroxysteroid-dehydrogenase-2, 17-hydroxylase/17-20-lyase, aromatase, and SF1 were significantly higher in endometriotic tissues. PGE2 induced the expression of all steroidogenic genes; production of progesterone, estrone, and estradiol; and StAR promoter activity in endometriotic cells. Overexpression of SF1 induced, whereas COUP-TFII or WT1 suppressed, StAR promoter activity. PGE2 induced coordinate binding of SF1 to StAR and aromatase promoters but decreased COUP-TFII binding in endometriotic cells. COUP-TFII or WT1 binding to both promoters was significantly higher in endometrial compared with endometriotic cells. CONCLUSION: Endometriotic cells contain the full complement of steroidogenic genes for de novo synthesis of estradiol from cholesterol, which is stimulated by PGE2 via enhanced binding of SF1 to promoters of StAR and aromatase genes in a synchronous fashion.


Subject(s)
Dinoprostone/pharmacology , Endometriosis/genetics , Estradiol/biosynthesis , Gene Expression Regulation, Enzymologic , Ovarian Diseases/genetics , Steroidogenic Factor 1/physiology , Adult , Cells, Cultured , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Endometriosis/enzymology , Endometriosis/metabolism , Endometrium/drug effects , Endometrium/metabolism , Female , Gene Expression Regulation, Enzymologic/drug effects , Humans , Middle Aged , Ovarian Diseases/enzymology , Ovarian Diseases/metabolism , Phosphoproteins/genetics , Phosphoproteins/metabolism , Progesterone/biosynthesis , Promoter Regions, Genetic/drug effects , Transcription, Genetic/drug effects , Young Adult
9.
Int J Neurosci ; 116(5): 565-74, 2006 May.
Article in English | MEDLINE | ID: mdl-16644517

ABSTRACT

Friedreich's ataxia (FRDA), the most common subtype of early onset hereditary spinocerebellar ataxia (SCA), is an autosomal recessive neurodegenerative disorder caused by unstable GAA tri-nucleotide expansions in the first intron of FRDA gene located at 9q13-q21.1 position. Results of GAA repeat polymorphism in 80 Turkish SCA patients and 38 family members of 11 typical FRDA patients were reported. GAA triplet repeat size ranged from approximately 7 to 34 in normal alleles and from approximately 66 to 1300 in mutant alleles. Twenty six patients were homozygous for GAA expansion and size of expanded alleles differed from approximately 425 to 1300 repeats. Children 2 and 6 years old (showing no ataxia symptoms) of one family had homozygous GAA expansions reaching approximately 925 repeats. All 11 families studied had at least 1 afflicted child and 9 parents and 2 siblings were carrier (heterozygous) with mutant alleles ranging from 66 to 850 repeats. Family studies confirmed the meiotic instability and stronger effect of expansion in the smaller alleles on phenotype and a negative correlation between GAA repeat expansion size and onset-age of the disease.


Subject(s)
Friedreich Ataxia/genetics , Iron-Binding Proteins/genetics , Polymorphism, Genetic , Trinucleotide Repeat Expansion/genetics , Adolescent , Adult , Child , DNA Mutational Analysis/methods , Family Health , Female , Humans , Male , Turkey/epidemiology , Frataxin
SELECTION OF CITATIONS
SEARCH DETAIL
...