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Schwab, M.

Publications and source records attributed to Schwab, M..

4 recordsLinked to original sources

Higher transcriptome stability during aging in long-lived giant mole-rats compared to short-lived rats

Many aging-associated physiological changes are known to come up in short- and long-lived species with a different trajectory and emerging evidence suggests that large parts of life history trait differences between species are based on inter-species variation in gene expression. Little information is yet available, however, about transcriptome changes during aging when comparing mammals with different lifespans. For this reason, we studied the transcriptomes of five tissues and two age cohorts in two similar sized rodent species with very different lifespans: rat (Rattus norvegicus) and giant mole-rat (Fukomys mechowii) with maximum lifespans of 3.8 and >20 years, respectively. Our results show that giant mole-rats exhibit higher transcriptome stability during aging than the rat. While well-known aging signatures (e.g. up-regulation of pro-inflammatory genes) were detected in all rat tissues, they showed up only in one giant mole-rat tissue. Furthermore, many differentially expressed genes that were found in both species, were regulated in opposite directions during aging. This suggests that expression changes that cause aging in short-lived species are counteracted in long-lived species. Taken together, transcriptome stability may be one key causal factor of the long life- and healthspan of giant mole-rats and maybe of African mole-rats in general.

systems biology

Long-lived rodents reveal signatures of positive selection in genes associated with lifespan and eusociality

The genetic mechanisms that determine lifespan are poorly understood. Most research has been done on short lived animals and it is unclear if these insights can be transferred to long-lived mammals like humans. Some African mole-rats (Bathyergidae) have life expectancies that are multiple times higher than similar sized and phylogenetically closely related rodents. We obtained genomic and transcriptomic data from 17 rodent species and systematically scanned eleven lineages associated with the evolution of longevity and eusociality for positively selected genes (PSGs). The set of 319 PSGs contains regulators of mTOR and is enriched in functional terms associated with (i) processes that are regulated by the mTOR pathway, e.g. translation, autophagy and mitochondrial biogenesis, (ii) the immune system and (iii) antioxidant defense. Analyzing gene expression of PSGs during aging in the long-lived naked mole-rat and up-regulation in the short-lived rat, we found a pattern fitting the antagonistic pleiotropy theory of aging.

evolutionary biology

Effects of Prenatal Stress on Structural Brain Development and Aging in Humans

Healthy brain aging is a major determinant of quality of life, allowing integration into society at all ages. Human epidemiological and animal studies indicate that in addition to lifestyle and genetic factors, environmental influences in prenatal life have a major impact on brain aging and age-associated brain disorders. The aim of this review is to summarize the existing literature on the consequences of maternal anxiety, stress, and malnutrition for structural brain aging and predisposition for age-associated brain diseases, focusing on studies with human samples. In conclusion, the results underscore the importance of a healthy mother-child relationship, starting in pregnancy, and the need for early interventions if this relationship is compromised.

neuroscience

Genetic variation in human drug-related genes

Variability in drug efficacy and adverse effects are observed in clinical practice. While the extent of genetic variability in classical pharmacokinetic genes is rather well understood, the role of genetic variation in drug targets is typically less studied. Based on 60,706 human exomes from the ExAC dataset, we performed an in-depth computational analysis of the prevalence of functional-variants in in 806 drug-related genes, including 628 known drug targets. We find that most genetic variants in these genes are very rare (f < 0.1%) and thus likely not observed in clinical trials. Overall, however, four in five patients are likely to carry a functional-variant in a target for commonly prescribed drugs and many of these might alter drug efficacy. We further computed the likelihood of 1,236 FDA approved drugs to be affected by functional-variants in their targets and show that the patient-risk varies for many drugs with respect to geographic ancestry. A focused analysis of oncological drug targets indicates that the probability of a patient carrying germline variants in oncological drug targets is with 44% high enough to suggest that not only somatic alterations, but also germline variants carried over into the tumor genome should be included in therapeutic decision-making.

bioinformatics