Cost-Effective Trap qPCR Approach to Evaluate Telomerase Activity: an Important Tool for Aging, Cancer, and Chronic Disease Research.

OBJECTIVES: Telomeres are a terminal "DNA cap" that prevent chromosomal fusion and degradation. However, aging is inherent to life, and so is the loss of terminal sequences. Telomerase is a specialized reverse transcriptase encoded by self-splicing introns that counteract chromosome erosion. Telomerase activity is observed during early embryonic development, but after the blastocyst stage, the expression of telomerase reduces. The consequences of either insufficient or unrestrained telomerase activity underscore the importance of ongoing studies aimed at elucidating the regulation of telomerase activity in humans. In the present study, we aimed to standardize a simplified telomerase repeat-amplification protocol (TRAP) assay to detect telomerase activity in unstimulated and PHA-stimulated mononuclear cells. METHODS AND RESULTS: Our optimized qPCR-based can efficiently evaluate telomerase activity. Quantification of protein and DNA between unstimulated and PHA-stimulated peripheral blood mononuclear cells revealed cellular activation and cell-cycle entry. The assay also showed that relative telomerase activity is significantly different between these two conditions, supporting the applicability of the assay. Furthermore, our findings corroborated that telomerase activity decreases with age. CONCLUSIONS: Telomeres and telomerase are implicated in aging and development of chronic diseases and cancer; however, difficulty in accessing commercial kits to investigate these aspects is a critical constraint in health surveillance studies. Our optimized assay was successfully used to differentiate telomerase activity between unstimulated and stimulated cells, clearly showing the reactivation of telomerase upon cell activation. This assay is affordable, reproducible, and can be executed in resource-limited settings.

Cost-Effective Trap qPCR Approach to Evaluate Telomerase Activity: an Important Tool for Aging, Cancer, and Chronic Disease Research

OBJECTIVES: Telomeres are a terminal "DNA cap" that prevent chromosomal fusion and degradation. However, aging is inherent to life, and so is the loss of terminal sequences. Telomerase is a specialized reverse transcriptase encoded by self-splicing introns that counteract chromosome erosion. Telomerase activity is observed during early embryonic development, but after the blastocyst stage, the expression of telomerase reduces. The consequences of either insufficient or unrestrained telomerase activity underscore the importance of ongoing studies aimed at elucidating the regulation of telomerase activity in humans. In the present study, we aimed to standardize a simplified telomerase repeat-amplification protocol (TRAP) assay to detect telomerase activity in unstimulated and PHA-stimulated mononuclear cells. METHODS and RESULTS: Our optimized qPCR-based can efficiently evaluate telomerase activity. Quantification of protein and DNA between unstimulated and PHA-stimulated peripheral blood mononuclear cells revealed cellular activation and cell-cycle entry. The assay also showed that relative telomerase activity is significantly different between these two conditions, supporting the applicability of the assay. Furthermore, our findings corroborated that telomerase activity decreases with age. CONCLUSIONS: Telomeres and telomerase are implicated in aging and development of chronic diseases and cancer; however, difficulty in accessing commercial kits to investigate these aspects is a critical constraint in health surveillance studies. Our optimized assay was successfully used to differentiate telomerase activity between unstimulated and stimulated cells, clearly showing the reactivation of telomerase upon cell activation. This assay is affordable, reproducible, and can be executed in resource-limited settings.

Preventing or reversing immunosenescence: can exercise be an immunotherapy?

There is now a strong body of evidence demonstrating that aging is accompanied by severe alterations in the immune system, a process known as immunosenescence. Among these changes are alterations in T-cell subpopulation size, cytokine secretion pattern, cell replicative capacity and antibody production, all of which culminate in a proinflammatory state called 'inflammaging' and a diminished capacity to respond to new antigens. These alterations are closely related to the increased mortality and morbidity rates observed in this population. However, the role of exercise on the prevention or treatment of immunosenescence is virtually unknown. Data gathered from the literature regarding the effects of physical activity on immune system aging are still limited and conflicting, with existing reports either advocating benefits or asserting a lack of evidence. Exercise as part of a healthy lifestyle has already been shown to provide long-term benefits with regard to cardiovascular, cognitive, psychosocial and other aspects of the elderly. If positive effects are also observed for immunosenescence, exercise could be a highly cost-effective measure to improve human quality of life compared with other strategies currently being pursued.