Prenatal stress and epigenetics Cao-Lei, L.; de Rooij, S.R.; King, S. ...
Neuroscience and biobehavioral reviews,
October 2020, 2020-10-00, 20201001, Letnik:
117
Journal Article
Recenzirano
•We outlined evidence from animal and human prenatal research supporting the view that prenatal stress could lead to lasting, broad and functionally organized signatures in DNA methylation which, in ...turn, could mediate exposure-phenotype associations.•We emphasized in this review the advantage of using stressors from quasi-randomly assigned experiments such as man-made disasters or natural disasters.•Although considerable discoveries have been made in prenatal research, we discussed the challenges that still need to be addressed in the future.
In utero exposure to environmental stress in both animals and humans could result in long-term epigenome alterations which further lead to consequences for adaptation and development in the offspring. Epigenetics, especially DNA methylation, is considered one of the most widely studied and well-characterized mechanisms involved in the long-lasting effects of in utero stress exposure. In this review, we outlined evidence from animal and human prenatal research supporting the view that prenatal stress could lead to lasting, broad and functionally organized signatures in DNA methylation which, in turn, could mediate exposure-phenotype associations. We also emphasized the advantage of using stressor from quasi-randomly assigned experiments. Furthermore, we discuss challenges that still need to be addressed in this field in the future.
Investigations of police performance during acutely stressful situations have primarily focused on higher-order cognitive processes like attention, affect or emotion and decision-making, and the ...behavioral outcomes of these processes, such as errors in lethal force. However, behavioral outcomes in policing must be understood as a combination of both higher-order processes and the physical execution of motor skills. What is missing from extant police literature is an understanding of how physiological responses to acute stress contribute to observed decrements in skilled motor performance at the neuromuscular level. The purpose of the current paper is to fill this knowledge gap in the following ways: (1) review scientific evidence for the physiological (i.e., autonomic, endocrine, and musculoskeletal) responses to acutely stressful exposures and their influence on skilled motor performance in both human and animal models, (2) review applied evidence on occupationally relevant stress physiology and observed motor decrements in performance among police, and (3) discuss the implications of stress physiology for police training and identify future directions for applied researchers. Evidence is compelling that skill decay is inevitable under high levels of acute stress; however, robust evidence-informed training practices can help mitigate this decay and contribute to officer safety.
In the current study we examined the effects of training in adult rats with a cervical spinal cord injury (SCI). One group of rats received 6 weeks of training in a single pellet reaching task ...immediately after injury, while a second group did not receive training. Following this period changes in cortical levels of BDNF and GAP-43 were analysed in trained and untrained animals and in a group with training but no injury. In another group of rats, functional recovery was analysed in the reaching task and when walking on a horizontal ladder. Thereupon, the cortical forelimb area was electrophysiologically examined using micro-stimulation followed by tracing of the lesioned corticospinal tract (CST). We found that trained rats improved substantially in the reaching task, when compared to their untrained counterparts. Trained rats however, performed significantly worse with their injured forelimb when walking on a horizontal ladder. In parallel to the improved recovery in the trained task, we found that the cortical area where wrist movements could be evoked by micro-stimulation expanded in trained rats in comparison to both untrained and uninjured rats. Furthermore, collateral sprouting of lesioned CST fibres rostral to the injury was increased in trained rats. Post-injury training was also found to increase cortical levels of GAP-43 but not BDNF. In conclusion we show that training of a reaching task promotes recovery of the trained task following partial SCI by enhancing plasticity at various levels of the central nervous system (CNS), but may come at the cost of an untrained task.
This article compares potential revenue from electric storage in retail and wholesale electric markets. The retail value can be extracted when storage responds to time-of-day retail prices. The ...wholesale value is enabled by the recent US Federal Energy Regulatory Commission Order 2222, which requires regional transmission operators (RTOs) to allow distributed storage behind the meter to participate in wholesale electric markets. To quantify the value of these markets, we use realistic time-of-day rates and market prices in one RTO’s ancillary service market. Formulae are developed to estimate the value of behind-the-meter storage in wholesale and retail markets, using an example electric vehicle in a fleet setting. The formulae are also used to compare whether or not net metering is available and different charging rates. The aggregate national storage behind the retail meter is very large, given the projected growth of electric vehicles. Our findings indicate the revenue from wholesale markets can be significantly more than that of retail opportunities. However, the potential in either retail or wholesale markets is currently limited by both state policy and incomplete RTO implementation of FERC orders.
To date, cellular transplantation therapy has not yet fulfilled its high expectations for cardiac repair. A major limiting factor is lack of long-term engraftment of the transplanted cells. ...Interestingly, transplanted cells can positively affect their environment via secreted paracrine factors, among which are extracellular vesicles, including exosomes: small bi-lipid-layered vesicles containing proteins, mRNAs, and miRNAs. An exosome-based therapy will therefore relay a plethora of effects, without some of the limiting factors of cell therapy. Since cardiomyocyte progenitor cells (CMPC) and mesenchymal stem cells (MSC) induce vessel formation and are frequently investigated for cardiac-related therapies, the pro-angiogenic properties of CMPC and MSC-derived exosome-like vesicles are investigated. Both cell types secrete exosome-like vesicles, which are efficiently taken up by endothelial cells. Endothelial cell migration and vessel formation are stimulated by these exosomes in in vitro models, mediated via ERK/Akt-signaling. Additionally, these exosomes stimulated blood vessel formation into matrigel plugs. Analysis of pro-angiogenic factors revealed high levels of extracellular matrix metalloproteinase inducer (EMMPRIN). Knockdown of EMMPRIN on CMPCs leads to a diminished pro-angiogenic effect, both in vitro and in vivo. Therefore, CMPC and MSC exosomes have powerful pro-angiogenic effects, and this effect is largely mediated via the presence of EMMPRIN on exosomes.
Genome-wide DNA methylation (DNAme) profiling of the placenta with Illumina Infinium Methylation bead arrays is often used to explore the connections between in utero exposures, placental pathology, ...and fetal development. However, many technical and biological factors can lead to signals of DNAme variation between samples and between cohorts, and understanding and accounting for these factors is essential to ensure meaningful and replicable data analysis. Recently, "epiphenotyping" approaches have been developed whereby DNAme data can be used to impute information about phenotypic variables such as gestational age, sex, cell composition, and ancestry. These epiphenotypes offer avenues to compare phenotypic data across cohorts, and to understand how phenotypic variables relate to DNAme variability. However, the relationships between placental epiphenotyping variables and other technical and biological variables, and their application to downstream epigenome analyses, have not been well studied. Using DNAme data from 204 placentas across three cohorts, we applied the PlaNET R package to estimate epiphenotypes gestational age, ancestry, and cell composition in these samples. PlaNET ancestry estimates were highly correlated with independent polymorphic ancestry-informative markers, and epigenetic gestational age, on average, was estimated within 4 days of reported gestational age, underscoring the accuracy of these tools. Cell composition estimates varied both within and between cohorts, as well as over very long placental processing times. Interestingly, the ratio of cytotrophoblast to syncytiotrophoblast proportion decreased with increasing gestational age, and differed slightly by both maternal ethnicity (lower in white vs. non-white) and genetic ancestry (lower in higher probability European ancestry). The cohort of origin and cytotrophoblast proportion were the largest drivers of DNAme variation in this dataset, based on their associations with the first principal component. This work confirms that cohort, array (technical) batch, cell type proportion, self-reported ethnicity, genetic ancestry, and biological sex are important variables to consider in any analyses of Illumina DNAme data. We further demonstrate the specific utility of epiphenotyping tools developed for use with placental DNAme data, and show that these variables (i) provide an independent check of clinically obtained data and (ii) provide a robust approach to compare variables across different datasets. Finally, we present a general framework for the processing and analysis of placental DNAme data, integrating the epiphenotype variables discussed here.
Although docosahexaenoic acid (DHA), an important dietary omega-3 polyunsaturated fatty acid (PUFA), is at present primarily sourced from marine fish, bioengineered crops producing DHA may offer a ...more sustainable and cost-effective source. DHA has been produced in transgenic oilseed crops, however, DHA in seed oil primarily occupies the sn-1/3 positions of triacylglycerol (TAG) with relatively low amounts of DHA in the sn-2 position. To increase the amount of DHA in the sn-2 position of TAG and in seed oil, putative lysophosphatidic acid acyltransferases (LPAATs) were identified and characterized from the DHA-producing alga Schizochytrium sp. and from soybean (Glycine max). The affinity-purified proteins were confirmed to have LPAAT activity. Expression of the Schizochytrium or soybean LPAATs in DHA-producing Arabidopsis expressing the Schizochytrium PUFA synthase system significantly increased the total amount of DHA in seed oil. A novel sensitive band-selective heteronuclear single quantum coherence (HSQC) NMR method was developed to quantify DHA at the sn-2 position of glycerolipids. More than two-fold increases in sn-2 DHA were observed for Arabidopsis lines expressing Schizochytrium or soybean LPAATs, with one Schizochytrium LPAAT driving DHA accumulation in the sn-2 position to 61% of the total DHA. Furthermore, expression of a soybean LPAAT led to a redistribution of DHA-containing TAG species, with two new TAG species identified. Our results demonstrate that transgenic expression of Schizochytrium or soybean LPAATs can increase the proportion of DHA at the sn-2 position of TAG and the total amount of DHA in the seed oil of a DHA-accumulating oilseed plant. Additionally, the band-selective HSQC NMR method that we developed provides a sensitive and robust method for determining the regiochemistry of DHA in glycerolipids. These findings will benefit the advancement of sustainable sources of DHA via transgenic crops such as canola and soybean.
Polyunsaturated fatty acids (PUFAs) are essential membrane components in higher eukaryotes and are the precursors of many lipid-derived signaling molecules. Here, pathways for PUFA synthesis are ...described that do not require desaturation and elongation of saturated fatty acids. These pathways are catalyzed by polyketide synthases (PKSs) that are distinct from previously recognized PKSs in both structure and mechanism. Generation of cis double bonds probably involves position-specific isomerases; such enzymes might be useful in the production of new families of antibiotics. It is likely that PUFA synthesis in cold marine ecosystems is accomplished in part by these PKS enzymes.
Highlights • Prenatal stress delivered over multiple consecutive generations causes widespread changes in brain signaling. • The field potential power was lower in the stressed line. • The coherence ...of field potentials across brain regions was increased in the stressed line. • We hypothesize that repeated prenatal stress causes a functional simplification of brain signaling.