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1.
J Assist Reprod Genet ; 30(6): 793-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23608779

RESUMO

PURPOSE: Telomere length plays a significant role in various disorders; however, its role in idiopathic recurrent pregnancy loss (iRPL) is not known. The objective of this study was to assess telomere length in peripheral blood leukocytes in couples experiencing unexplained recurrent pregnancy loss (iRPL). METHODS: The study included 25 couples experiencing iRPL and 20 controls. The mean relative telomere length was measured by quantitative Real Time PCR (Q-PCR) based assay, which measures the average ratio of telomere repeat copy number to a single copy gene (36B4) copy number (T/S ratio) in each sample. RESULTS: The relative leukocyte mean telomere length (T/S) in both men and women from iRPL group was significantly lower (p < 0.05) when compared to controls. A significant (P < 0.05) negative correlation was found between age and leukocyte telomere length (T/S ratio). Among the sperm parameters seminal volume was found to be negatively (r = -0.4679) associated with the telomere T/S ratio. The DNA fragmentation index of sperm showed positive correlation (r = 0.4744) with telomere length. In this preliminary study, we found that shorter telomere length in both men and women may be associated with early pregnancy loss. CONCLUSION: In conclusion, shorter telomere length in both male and female partners appears to play a role in the idiopathic recurrent pregnancy loss. Loss of telomeric DNA due to oxidative stress needs further analysis. Analysis of telomere length in germ cells are needed to further substantiate the findings of this study.


Assuntos
Aborto Habitual/genética , Leucócitos/citologia , Homeostase do Telômero/genética , Aborto Habitual/etiologia , Aborto Habitual/patologia , Adulto , Feminino , Humanos , Masculino , Estresse Oxidativo/genética , Gravidez , Espermatozoides/patologia , Telômero/genética
2.
Andrologia ; 45(5): 289-304, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22928904

RESUMO

Telomeres, noncoding hexameric tandem repeats located at the ends of chromosomes, maintain chromosome stability and genome integrity. These guanine-rich repeats are highly conserved during evolution, and their role is dependent on their length and structure. They have multiple functions, including regulating the reproductive lifespan by mediating synapsis and homologous recombination of the chromosomes. Short telomeres result in meiotic arrest, segregation abnormalities and dysjunction, which lead to an increased incidence of aneuploid germ cells. In addition, shortened telomeres in men result in apoptosis of germ cells, whereas, in women, they result in meiotic arrest. In somatic cells, telomere shortening occurs at each consecutive round of replication, which induces senescence in vitro and in vivo. However there is a 2-fold elongation of telomeres during spermatogenesis. Spermatozoa, are terminally differentiated cells, have longer telomeres than spermatogonia and pachytene spermatocytes. In addition to genetic factors, lifestyle factors and psychological stress also play crucial role in modulating telomere length. Because not much is known about its role in reproduction, we focused this review on the function, structure and length dynamics of the telomere in the reproductive process.


Assuntos
Telômero/fisiologia , Feminino , Humanos , Masculino , Reprodução/genética , Reprodução/fisiologia , Espermatogênese/genética , Espermatozoides/fisiologia , Proteínas Semelhantes à Proteína de Ligação a TATA-Box , Telômero/ultraestrutura
3.
Arch Gynecol Obstet ; 287(4): 803-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23179801

RESUMO

PURPOSE: Telomeres are multifunctional nucleoprotein domains with hexanucleotide tandem repeat (5' TTAGGG 3') sequences, which cap the chromosome ends. However, the role of telomere and its length in sperm with regard to fertility remains unknown. METHODS: In this pilot study, we analyzed 32 idiopathic infertile men and 25 controls for sperm telomere length by quantitative polymerase chain reaction (Q-PCR), and correlated it with sperm DNA fragmentation index (DFI) and reactive oxygen species (ROS) levels. RESULTS: The relative sperm mean telomere length (T/S) of infertile men was found to be significantly lower (p < 0.005) when compared to controls (0.674 ± 0.028 vs. 0.699 ± 0.030). None of the sperm parameters such as sperm count, forward motility, morphology, ROS, and DFI were found to correlate with the sperm telomere length. CONCLUSION: Shorter telomeres in sperm may be one of the causative factors responsible for male infertility, but further detailed studies are needed to confirm these findings.


Assuntos
Fragmentação do DNA , Infertilidade Masculina/patologia , Espermatozoides/patologia , Telômero/patologia , Estudos de Casos e Controles , Humanos , Infertilidade Masculina/metabolismo , Masculino , Projetos Piloto , Espécies Reativas de Oxigênio/metabolismo , Sêmen/metabolismo
5.
Arch Gynecol Obstet ; 284(6): 1577-84, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21779778

RESUMO

PURPOSE: Etiology in majority of couples experiencing recurrent spontaneous abortions (RSA) is still unknown. The aim of the study was to find the role of cytogenetic abnormalities, Y chromosome microdeletion, oxidative stress (OS) and sperm DNA fragmentation in male partners of couples experiencing RSA. METHODS: Forty-eight couples with history of RSA and 20 fertile controls were included in the study. The study subjects were divided into male partners of RSA couples with abnormal sperm parameters (SA) (N = 16), male partners of RSA couples with normal sperm parameters (NS) (N = 32) and age-matched fertile controls with normal sperm parameters (FC) (N = 20). RESULTS: One of 48 men (2%) showed 46, XY (1qh-) chromosomal complement. None of the cases including FC showed deletion in any of the 3 AZF loci on Y chromosome long arm. Sperm count was found be significantly lower in SA cases as compared to group NS cases (P < 0.0001) and FC (P < 0.005). Sperm forward motility was found to be significantly (P < 0.05) lower in SA cases as compared to NS and FC. Male partners of RSA couples with abnormal sperm parameters had higher reactive oxygen species (ROS) levels (P < 0.005) and sperm DNA damage (P < 0.0001), however, in male partners of RSA couples with normal sperm parameters had only increased (P < 0.0001) sperm DNA damage. CONCLUSION: Other than chromosomal anomalies, sperm DNA fragmentation and seminal OS may be the underlying pathology in RSA, thus screening for seminal ROS levels and DNA fragmentation has diagnostic and prognostic capabilities.


Assuntos
Aborto Habitual/genética , Estresse Oxidativo , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Espermatozoides/ultraestrutura , Aborto Habitual/etiologia , Aborto Habitual/metabolismo , Adulto , Estudos de Casos e Controles , Cromatina/ultraestrutura , Deleção Cromossômica , Cromossomos Humanos Y/genética , Cromossomos Humanos Y/metabolismo , Fragmentação do DNA , Feminino , Humanos , Infertilidade Masculina , Masculino , Espécies Reativas de Oxigênio/metabolismo , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/metabolismo , Contagem de Espermatozoides , Espermatozoides/metabolismo
6.
Fitoterapia ; 79(2): 79-81, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17850989

RESUMO

The ethanol extract of flowers of Hibiscus rosasinensis at doses of 250 mg/kg and 500 mg/kg significantly reduced the blood glucose level in both acute (1, 3, 5 h) and sub acute (1, 3, 5, 7 days) treatments.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hibiscus/química , Hipoglicemiantes/análise , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Feminino , Flores/química , Hipoglicemiantes/uso terapêutico , Masculino , Ratos , Ratos Wistar
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