RESUMO
Studies have shown that estrogen replacement therapy and estrogen plus progestin replacement therapy alter serum levels of total, LDL and HDL cholesterol levels. However, HDL cholesterol levels in women vary considerably in response to hormone replacement therapy (HRT). A significant portion of the variability of these levels has been attributed to genetic factors. Therefore, we investigated the influence of estrogen receptor-alpha (ESR1) gene polymorphisms on HDL levels in response to postmenopausal HRT. We performed a prospective cohort study on 54 postmenopausal women who had not used HRT before the study and had no significant general medical illness. HRT consisted of conjugated equine estrogen and medroxyprogesterone acetate continuously for 1 year. The lipoprotein levels were measured from blood samples taken before the start of therapy and after 1 year of HRT. ESR1 polymorphism (MspI C>T, HaeIII C>T, PvuII C>T, and XbaI A>G) frequencies were assayed by restriction fragment length polymorphism. A general linear model was used to describe the relationships between HDL levels and genotypes after adjusting for age. A significant increase in HDL levels was observed after HRT (P = 0.029). Women with the ESR1 PvuII TT genotype showed a statistically significant increase in HDL levels after HRT (P = 0.032). No association was found between other ESR1 polymorphisms and HDL levels. According to our results, the ESR1 PvuII TT genotype was associated with increased levels of HDL after 1 year of HRT.
Assuntos
Feminino , Humanos , Pessoa de Meia-Idade , HDL-Colesterol/sangue , Terapia de Reposição de Estrogênios , Receptor alfa de Estrogênio/genética , Estrogênios Conjugados (USP)/uso terapêutico , Acetato de Medroxiprogesterona/uso terapêutico , Polimorfismo Genético/genética , Estudos de Coortes , HDL-Colesterol/genética , Genótipo , Polimorfismo de Fragmento de Restrição , Estudos ProspectivosRESUMO
OBJECTIVE: To investigate the association between the CYP17alpha gene polymorphism and hot flushes in postmenopausal women. METHODS: Ninety-three non-hysterectomized, postmenopausal women were enrolled in this study. Vasomotor symptoms were assessed at the baseline visit and based on information provided by each participant. The genotypic polymorphism of CYP17alpha gene was analyzed by PCR-RFLP assay using genomic DNA isolated from peripheral blood lymphocytes. RESULTS: Thirty-six women reported hot flushes of mild intensity, 25 reported hot flushes of moderate intensity and 32 of severe intensity. There was no significant difference between the severity of hot flushes and the CYP17 genotype or allele frequencies, 0.58 and 0.67 respectively. No association was found between hot flush severity and the CYP17 allele (odds ratio = 1.17, p = 0.61). CONCLUSION: The results of this study suggest that the CYP17 MspAI polymorphism was not significantly associated with an increased risk of reporting hot flushes.
Assuntos
Fogachos/genética , Pós-Menopausa , Esteroide 17-alfa-Hidroxilase/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Índice de Gravidade de DoençaRESUMO
A decrease in ribosomal gene activity is an essential feature of the aging process as it was observed in Alzheimer's disease, in elderly Down's patients and in elderly healthy people. It is well known that aging is also associated with a reduction in melatonin synthesis. We studied 24 male Wistar rats cytogenetically, by using Ag-stained NOR (6 three-month-old rats underwent pinealectomy and were studied after 20 days; 6 control rats of the same age; 6 three-month-old rats underwent pinealectomy and were studied after 8 months; 6 control rats of the same age). Our results indicate that the absence of the pineal gland leads to a decrease in NOR activity. Further studies are necessary to determine if pinealectomy in rats could provide an animal model for aging.
Assuntos
Envelhecimento/genética , Região Organizadora do Nucléolo/fisiologia , Glândula Pineal/fisiologia , Ribossomos , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Animais , Masculino , Melatonina/metabolismo , Glândula Pineal/cirurgia , Ratos , Ratos WistarRESUMO
DNA methylation is an epigenetic mechanism controlling of gene expression. We studied the effect of a demethylation agent 5-azacytidine, on ribosomal gene activity observed by Nucleolus Staining Giemsa in the chromosomes of eight Alzheimer's disease patients, eight elderly healthy individuals and eight young healthy controls. Metaphase cells were obtained from lymphocyte cultures. All the acrocentric chromosome pairs were analyzed using G banding followed by Nucleolus Staining Giemsa banding in the same cell. The Alzheimer's disease patients and elderly healthy control did not show a variation in the transcriptional activity of ribosomal genes with or without 5-azacytidine treatment, whereas the young control group showed an increase in this activity with the treatment.
