SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Immortality

209

Life stress resulting from early-life experiences and domestic stress is linked with shorter leukocyte telomere length (LTL), but evidence on employment-related stress is scarce. We explored whether unemployment in early adulthood is associated with shorter LTL, a potential biomarker of premature aging.

Concepts: Death, Senescence, Biology, Cell division, Telomerase, Telomere, Immortality

182

Leucocyte telomere length (LTL) shortening is associated with cardiovascular ischemic events and mortality in humans, but data on its association with subclinical atherosclerosis are scarce. Whether the incidence and severity of subclinical atherosclerosis are associated with the abundance of critically short telomeres, a major trigger of cellular senescence, remains unknown.

Concepts: Death, Senescence, Cell division, Radical, Telomerase, Telomere, Maximum life span, Immortality

41

Psychological stress is suggested to accelerate the rate of biological aging. We investigated whether work-related exhaustion, an indicator of prolonged work stress, is associated with accelerated biological aging, as indicated by shorter leukocyte telomeres, that is, the DNA-protein complexes that cap chromosomal ends in cells.

Concepts: DNA, Gene, Senescence, Cell division, Telomerase, Telomere, Acceleration, Immortality

26

Food is medicine and vice versa. In Hindu and Ayurvedic medicine, and among human cultures of the Indian subcontinent in general, the perception of the food-medicine continuum is especially well established. The preparation of the exhilarating, gold-coloured Soma, Amrita or Ambrosia, the elixir and food of the ‘immortals’ - the Hindu pantheon -, by the ancient Indo-Aryans, is described in the Rigveda in poetic hymns. Different theories regarding the botanical identity of Soma circulate, but no pharmacologically and historically convincing theory exists to date.

Concepts: Indian subcontinent, Soma, Hinduism, Immortality, Vedas, Indra, Sanskrit words and phrases, Hindu mythology

15

Telomere extension has been proposed as a means to improve cell culture and tissue engineering and to treat disease. However, telomere extension by nonviral, nonintegrating methods remains inefficient. Here we report that delivery of modified mRNA encoding TERT to human fibroblasts and myoblasts increases telomerase activity transiently (24-48 h) and rapidly extends telomeres, after which telomeres resume shortening. Three successive transfections over a 4 d period extended telomeres up to 0.9 kb in a cell type-specific manner in fibroblasts and myoblasts and conferred an additional 28 ± 1.5 and 3.4 ± 0.4 population doublings (PD), respectively. Proliferative capacity increased in a dose-dependent manner. The second and third transfections had less effect on proliferative capacity than the first, revealing a refractory period. However, the refractory period was transient as a later fourth transfection increased fibroblast proliferative capacity by an additional 15.2 ± 1.1 PD, similar to the first transfection. Overall, these treatments led to an increase in absolute cell number of more than 10(12)-fold. Notably, unlike immortalized cells, all treated cell populations eventually stopped increasing in number and expressed senescence markers to the same extent as untreated cells. This rapid method of extending telomeres and increasing cell proliferative capacity without risk of insertional mutagenesis should have broad utility in disease modeling, drug screening, and regenerative medicine.-Ramunas, J., Yakubov, E., Brady, J. J., Corbel, S. Y., Holbrook, C., Brandt, M., Stein, J., Santiago, J. G., Cooke, J. P., Blau, H. M. Transient delivery of modified mRNA encoding TERT rapidly extends telomeres in human cells.

Concepts: DNA, Senescence, Cell division, DNA replication, Telomerase, Telomere, Transfection, Immortality

7

The potential to reverse aging has long been a tantalizing thought, but has equally been considered mere utopia. Recently, the spotlights have turned to senescent cells as being a culprit for aging. Can these cells be therapeutically eliminated? When so? And is this even safe? Recent developments in the tool box to study senescence have made it possible to begin addressing these questions. It will be especially relevant to identify how senescence impairs tissue rejuvenation and to prospectively design compounds that can both target senescence and stimulate rejuvenation in a safe manner. This review argues that to fulfill this niche, cell-penetrating peptides may provide promising therapeutics. As a candidate approach, the author also highlights the potential of targeting individual FOXO signaling pathways to combat senescence and stimulate tissue rejuventaion.

Concepts: Death, Senescence, Gerontology, Telomere, Ageing, Aging, Maximum life span, Immortality

3

Research into human development involves the use of human embryos and their derivative cells and tissues. How religions view the human embryo depends on beliefs about ensoulment and the inception of personhood, and science can neither prove nor refute the teaching of those religions that consider the zygote to be a human person with an immortal soul. This Spotlight article discusses some of the dominant themes that have emerged with regard to how different religions view the human embryo, with a focus on the Christian faith as well as Buddhist, Hindu, Jewish and Islamic perspectives.

Concepts: Embryo, Developmental biology, Religion, Buddhism, Christianity, Soul, Jainism, Immortality

1

Many people believe in immortality, but who is perceived to live on and how exactly do they live on? Seven studies reveal that good- and evil-doers are perceived to possess more immortality-albeit different kinds. Good-doers have “transcendent” immortality, with their souls persisting beyond space and time; evil-doers have “trapped” immortality, with their souls persisting on Earth, bound to a physical location. Studies 1 to 4 reveal bidirectional links between perceptions of morality and type of immortality. Studies 5 to 7 reveal how these links explain paranormal perceptions. People generally tie paranormal events to evil spirits (Study 5), but this depends upon location: Evil spirits are perceived to haunt houses and dense forests, whereas good spirits are perceived in expansive locations such as mountaintops (Study 6). However, even good spirits may be seen as trapped on Earth given extenuating circumstances (Study 7). Materials include a scale for measuring trapped and transcendent immorality.

Concepts: Psychology, Understanding, Mind, Soul, Immortality, Christian terms, Spirit, Ghost

1

Five studies tested the effects that soul beliefs have on reactions to end-of-the-world scenarios. In Studies 1 and 2, participants who firmly believe in an immortal soul showed less resistance to an article predicting the end of humanity than those without such belief. However, in Studies 3 to 5, thoughts of symbolic immortality made soul believers more resistant to scientific evidence predicting the end of humanity. These results suggest that belief in an immortal soul provides psychological protection against the threat of humanity’s demise that does not hold for symbolic immortality beliefs.

Concepts: Scientific method, Psychology, Critical thinking, Cognition, Philosophy of mind, Mind, Soul, Immortality

0

Telomere maintenance protects the cell against genome instability and senescence. Accelerated telomere attrition is a characteristic of premature aging syndromes including Dyskeratosis congenita (DC). Mutations in hRTEL1 are associated with a severe form of DC called Hoyeraal-Hreidarsson syndrome (HHS). HHS patients carry short telomeres and HHS cells display telomere damage. Here we investigated how hRTEL1 contributes to telomere maintenance in human primary as well as tumor cells. Transient depletion of hRTEL1 resulted in rapid telomere shortening only in the context of telomerase-positive cells with very long telomeres and high levels of telomerase. The effect of hRTEL1 on telomere length is telomerase dependent without impacting telomerase biogenesis or targeting of the enzyme to telomeres. Instead, RTEL1 depletion led to a decrease in both G-overhang content and POT1 association with telomeres with limited telomere uncapping. Strikingly, overexpression of POT1 restored telomere length but not the overhang, demonstrating that G-overhang loss is the primary defect caused by RTEL1 depletion. We propose that hRTEL1 contributes to the maintenance of long telomeres by preserving long G-overhangs, thereby facilitating POT1 binding and elongation by telomerase.

Concepts: DNA, Cancer, Senescence, Cell division, DNA replication, Telomerase, Telomere, Immortality