Navegando por Palavras-chave "Telomere length"
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- ItemAcesso aberto (Open Access)Comprimento telomérico associado a estresse em crianças: uma revisão sistemática(Universidade Federal de São Paulo (UNIFESP), 2016-03-17) Coimbra, Bruno Messina [UNIFESP]; Belangero, Sintia Iole Nogueira [UNIFESP]; http://lattes.cnpq.br/2623781262478620; http://lattes.cnpq.br/1311587762000993; Universidade Federal de São Paulo (UNIFESP)Telomeres are repetitive DNA sequences (T2AG3)n present at the ends of the chromatids and provide stability and protection to the DNA molecular structure. Due to the incapacity of the polymerase enzyme to replicate the DNA molecule in its full extent, the length of the telomeric DNA shortens after each cell division. When telomere length shortens to a critical level, DNA defensive mechanisms lead cells to either a state of arrest (senescence) or apoptosis. There is robust amount of evidence that chronic psychological stress speeds the erosion of telomeres. However, only a limited number of studies primarily focused on the association between stress and telomere length in children, and it is still unclear whether young individuals show signs of cellular aging early in life. We conducted a systematic review of studies that investigated the association between stress and telomeres in groups of children aged from three to fifteen years old. Eleven papers met our criteria. The eligible papers used various methodologies and DNA collection methods. Although unable to perform a meta-analysis, we found a relevant association between stress and telomere shortening in children. Stress induced by adversities and difficulties is probable cause for telomere decline from an early age. We believe that further longitudinal studies with multiple telomere measurements in large groups should be encouraged for better assessment of telomere trajectory in psychologically stressed children.
- ItemSomente MetadadadosLeukocyte telomere length variation in different stages of schizophrenia(Pergamon-Elsevier Science Ltd, 2018) Maurya, Pawan Kumar [UNIFESP]; Rizzo, Lucas Bortolotto [UNIFESP]; Xavier, Gabriela [UNIFESP]; Tempaku, Priscila Farias [UNIFESP]; Ota, Vanessa Kiyomi [UNIFESP]; Santoro, Marcos L. [UNIFESP]; Spindola, Leticia M. [UNIFESP]; Moretti, Patricia S. [UNIFESP]; Mazzotti, Diego R.; Gadelha, Ary [UNIFESP]; Gouvea, Eduardo S.; Noto, Cristiano [UNIFESP]; Maes, Michael; Cordeiro, Quirino; Bressan, Rodrigo A. [UNIFESP]; Brietzke, Elisa [UNIFESP]; Belangero, Sintia Iole [UNIFESP]Recent research has demonstrated that telomere maintenance might be a key integrating point for the cumulative effect of genetic and environmental factors in patients with first-episode psychosis (FEP) and schizophrenia (SCZ). Eighty-one participants with antipsychotic-naive FEP, 173 with SCZ and 438 HC were enrolled in this study. Psychiatric diagnosis was assessed using the Semi-Structured Clinical Interview for DSM-IV Axis-I (SCID-I). The Positive and Negative Syndrome Scale (PANSS), Young Mania Rating Scale (YMRS) and Calgary Depression Scale for Schizophrenia (CDSS) were used to measure symptoms severity. Telomere length (TL) was determined using a multiplex qPCR assay. After adjustment for age, years of education, and smoking status, we found that patients with SCZ had longer TL (relative ratio (RR) = 1.08) than the HC group (RR = 1.00, Wald chi(2) = 12.48, p = 0.002). Further, non-remitted SCZ patients presented longer TL (RR = 1.00) compared to remitted SCZ (RR = 0.88, Wald chi(2) = 7.20, p = 0.007). TL in patients also correlated to psychopathology assessment in terms of total (p = 0.003) and positive PANSS scores (p = 0.001). No correlation with negative PANSS, YMRS, and CDSS or effects of medication was found on TL. Although the exact pathways underlying longer TL in SCZ patients remain unclear, these findings raise more questions than answers and suggest that TL may be of immense value on SCZ progression. Further studies are required to investigate the association of TL in FEP and SCZ.
- ItemSomente MetadadadosStress-related telomere length in children: A systematic review(Pergamon-Elsevier Science Ltd, 2017) Coimbra, Bruno Messina [UNIFESP]; Carvalho, Carolina Muniz [UNIFESP]; Moretti, Patricia Natalia [UNIFESP]; Mello, Marcelo Feijo [UNIFESP]; Belangero, Sintia I. [UNIFESP]Telomeres are repetitive DNA sequences at the ends of chromatids that shorten following each cell replication. Once telomeres reach a critical length, DNA defense mechanisms can direct cells to either a state of arrest (senescence) or apoptosis. Stress induced by adversity is a probable cause of accelerated telomere shortening from an early age. However, few studies have examined the association between stress and telomere length in children, and it remains unclear whether young individuals may show signs of cellular aging early in life. Our aim was to examine whether adversity in childhood is associated with shortening of telomere length. We conducted a systematic review of studies that investigated the association between stress and telomere length in children from 3 to 15 years of age. Eleven studies met our selection criteria. We concluded that adversity in childhood (such as violence, low socioeconomic status, maternal depression, family disruption, and institutionalization) have an impact on telomere length. This suggests that exposed individuals show signs of accelerated erosion of telomeric ends from an early age. We discuss whether telomere shortening is related to negative health outcomes later in life or could be a biomarker predicting health outcomes. We believe that further large-scale longitudinal studies that repeatedly monitor telomere length are very important for providing a better assessment of telomere trajectory in psychologically stressed children. This will verify the extent to which adversity impacts upon the biological development of cell aging in childhood. (C) 2017 Elsevier Ltd. All rights reserved.
- ItemSomente MetadadadosTelomere length as a marker of sleep loss and sleep disturbances: a potential link between sleep and cellular senescence(Elsevier B.V., 2015-05-01) Tempaku, Priscila F. [UNIFESP]; Mazzotti, Diego R. [UNIFESP]; Tufik, Sergio [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The identification of biological markers that allow the early diagnosis, or even the prevention of age-related diseases, is an important goal that is being actively pursued in the research community. Sleep is one of the physiological processes that is most affected by aging, and there is a strong relationship between age-related sleep alterations and diseases. Changes in cellular senescence and the linked changes in telomere length might be potential markers of age-related sleep changes. in this review, we present some of the most recent evidence showing that telomere length has been associated with sleep loss and sleep disturbances in cross-sectional and case-control studies. We also present insights into the cellular senescence mechanisms relating to changes in telomere length, and we suggest that this field lacks basic and clinical research studies, especially long-term longitudinal studies, which may bring opportunities to sleep researchers to investigate this relationship in more depth. (C) 2015 Elsevier B.V. All rights reserved.