Highlights ► That animals do not senesce in their natural environment is an oft-quoted fallacy. ► Reviewing studies of wild animals, we find evidence for senescence in 175 species. ► Recent field ...studies are shedding new light on key bio-gerontological questions. ► Ecological studies help establish the generality of findings from model organisms. ► Tests of evolutionary theories of ageing demand research in natural settings.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
γ-Aminobutyric acid (GABA), a major inhibitory neurotransmitter in the mammalian central nervous system, is involved in sleep physiology. Caffeine is widely used psychoactive substance known to ...induce wakefulness and insomnia to its consumers. This study was performed to examine whether GABA extracts from fermented rice germ ameliorates caffeine-induced sleep disturbance in mice, without affecting spontaneous locomotor activity and motor coordination. Indeed, caffeine (10 mg/kg, i.p.) delayed sleep onset and reduced sleep duration of mice. Conversely, rice germ ferment extracts-GABA treatment (10, 30, or 100 mg/ kg, p.o.), especially at 100 mg/kg, normalized the sleep disturbance induced by caffeine. In locomotor tests, rice germ ferment extracts-GABA slightly but not significantly reduced the caffeine-induced increase in locomotor activity without affecting motor coordination. Additionally, rice germ ferment extracts-GABA per se did not affect the spontaneous locomotor activity and motor coordination of mice. In conclusion, rice germ ferment extracts-GABA supplementation can counter the sleep disturbance induced by caffeine, without affecting the general locomotor activities of mice.
Highlights • Disruption of circadian rhythms leads to inflammation, cancer, and reduced life expectancy. • Robust rhythms lead to well-being and increased longevity. • Circadian rhythms change as the ...organism ages as a result of blunted SCN entrainment and/or reduced SCN output. • Feeding regimens affect circadian rhythms by resetting and/or increasing the amplitude of gene and protein expression, which may lead to improved health and/or increased life span.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Autism spectrum disorder (ASD) remains unexplained and untreated despite the high attention of research in recent years. Aside from its various characteristics is the baffling male preponderance over ...the female population. Using a validated animal model of ASD which is the telomerase reverse transcriptase overexpressing mice (TERT-tg), we conducted ASD-related behavioral assessments and protein expression experiments to mark the difference between male and females of this animal model. After statistically analyzing the results, we found significant effects of TERT overexpression in sociability, social novelty preference, anxiety, nest building, and electroseizure threshold in the males but not their female littermates. Along these differences are the male-specific increased expressions of postsynaptic proteins which are the NMDA and AMPA receptors in the prefrontal cortex. The vGluT1 presynaptic proteins, but not GAD, were upregulated in both sexes of TERT-tg mice, although it is more significantly pronounced in the male group. Here, we confirmed that the behavioral effect of TERT overexpression in mice was male-specific, suggesting that the aberration of this gene and its downstream pathways preferentially affect the functional development of the male brain, consistent with the male preponderance in ASD.
Telomere length (TL) has become a biomarker of increasing interest within ecology and evolutionary biology, and has been found to predict subsequent survival in some recent avian studies but not ...others. Here, we undertake the first formal meta-analysis to test whether there is an overall association between TL and subsequent mortality risk in vertebrates other than humans and model laboratory rodents. We identified 27 suitable studies and obtained standardized estimates of the hazard ratio associated with TL from each. We performed a meta-analysis on these estimates and found an overall significant negative association implying that short telomeres are associated with increased mortality risk, which was robust to evident publication bias. While we found that heterogeneity in the hazard ratios was not explained by sex, follow-up period, maximum lifespan or the age group of the study animals, the TL–mortality risk association was stronger in studies using qPCR compared to terminal restriction fragment methodologies. Our results provide support for a consistent association between short telomeres and increased mortality risk in birds, but also highlight the need for more research into non-avian vertebrates and the reasons why different telomere measurement methods may yield different results.
This article is part of the theme issue ‘Understanding diversity in telomere dynamics’.
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This text aims to initiate a dialogue between the works of Martin Buber and Jacques Derrida with regard to the notion of ‘reciprocity’. It is my contention that a reexamination of Buber’s notion of ...relation will reveal a reflection, devoid of any notions of ‘symmetry’, which strongly indicates a point of continuity with Derrida’s late thinking on hospitality. The following text, therefore, aims to provoke a reexamination of Buber’s thinking on the home, at the centre of which stands the notion entirely opposed to ‘symmetry’: namely, ‘reciprocity’. The hypothesis of this text, then, is that when it comes to thinking of dwelling, Buber and Derrida share a ‘relational’ way of thinking, which foregrounds the relation between — in Buber’s case — the relations between man and God, man and man, and man and the Land, and — in Derrida’s case — between guest and host; in addition, I will attempt to show that Derrida’s work on hospitality — in particular, his introduction of a notion of ‘identity’ — produces a necessary contribution, or response, to Buber’s notion of ‘dwelling as reciprocity’. I will conclude by reflecting upon the reciprocity of this dialogue between the work of Martin Buber and Jacques Derrida.
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We reexamined the efficacy of Pathways early autism intervention using generalized measures of social communication and language skills administered by an unfamiliar adult in a novel environment. ...Generalized measures improve on sources of measurement bias. Sixty-seven autistic children blocked on age (under versus over 3 years) were randomly assigned to 15 weeks of Pathways or services-as-usual. Age moderated the effects of Pathways for social communication. Specifically, Pathways had a significantly large effect for children under 3 and a small effect that approached significance for children over 3. Pathways also had a small effect on expressive speech/language skills. Results replicate previous findings of the efficacy of Pathways on proximal and distal skills and support the importance of early intervention.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, ODKLJ, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
Cytochrome P450 (CYP) is a diverse superfamily of hemoproteins found in a large number of organisms. Most cytochrome P450 enzymes have monooxygenase activity and are involved in detoxification and ...hormone and lipid metabolism. In drug metabolism, the chemical modification or degradation of chemicals including exogenous and endogenous compounds, cytochrome P450 is probably the most important element of oxidative metabolism. The present understanding of the mechanisms of induction of cytochrome P450 enzymes and their regulation has made considerable progress during the last few years. However, it remains the subject of intense scientific research to better understand how the expression of cytochrome P450 enzymes is regulated at the molecular level. It has been known for three decades that the expression of cytochrome P450 gene family members is regulated by the biological clock. In addition, hepatic P450 monooxygenases metabolize melatonin, the pineal hormone whose expression is controlled by the biological clock and, in turn, resets the biological clock. This review will summarize our present understanding on how the biological clock regulates the expression and activity of cytochrome P450 enzymes to affect pharmacokinetics and detoxification and hormone and lipid metabolism and how melatonin metabolism and cytochrome P450 enzyme activity can affect circadian rhythms in mammals.
Time-restricted feeding (TRF) limits the time and duration of food availability without calorie reduction. Although a high-fat (HF) diet leads to disrupted circadian rhythms, TRF can prevent ...metabolic diseases, emphasizing the importance of the timing component. However, the question of when to implement the feeding window and its metabolic effect remains unclear, specifically in obese and metabolically impaired animals. Our aim was to study the effect of early vs. late TRF-HF on diet-induced obese mice in an 8:16 light–dark cycle. C57BL male mice were fed ad libitum a high-fat diet for 14 weeks after which they were given the same food during the early (E-TRF-HF) or late (L-TRF-HF) 8 h of the dark phase for 5 weeks. The control groups were fed ad libitum either a high-fat (AL-HF) or a low-fat diet (AL-LF). Respiratory exchange ratio (RER) was highest for the AL-LF group and the lowest for the AL-HF group. E-TRF-HF led to lower body weight and fat depots, lower glucose, C-peptide, insulin, cholesterol, leptin, TNFα, and ALT levels compared with L-TRF-HF- and AL-HF-fed mice. TRF-HF regardless whether it was early or late led to reduced inflammation and fat accumulation compared with AL-HF-fed mice. E-TRF-HF led to advanced liver circadian rhythms with higher amplitudes and daily expression levels of clock proteins. In addition, TRF-HF led to improved metabolic state in muscle and adipose tissue. In summary, E-TRF-HF leads to increased insulin sensitivity and fat oxidation and decreased body weight, fat profile and inflammation contrary to AL-HF-fed, but comparable to AL-LF-fed mice. These results emphasize the importance of timed feeding compared to ad libitum feeding, specifically to the early hours of the activity period.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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