Life Stages Research Articles

Efficient enzyme-free method to assess the development and maturation of the innate and adaptive immune systems in the mouse colon

Researchers who aim to globally analyze the gastrointestinal immune system via flow cytometry have many protocol options to choose from, with specifics generally tied to gut wall layers of interest. To get a clearer idea of the approach we should use on full-thickness colon samples from mice, we first undertook a systematic comparison of three tissue dissociation techniques: two based on enzymatic cocktails and the other one based on manual crushing. Using flow cytometry panels of general markers of lymphoid and myeloid cells, we found that the presence of cell-surface markers and relative cell population frequencies were more stable with the mechanical method. Both enzymatic approaches were associated with a marked decrease of several cell-surface markers. Using mechanical dissociation, we then developed two minimally overlapping panels, consisting of a total of 26 antibodies, for serial profiling of lymphoid and myeloid lineages from the mouse colon in greater detail. Here, we highlight how we accurately delineate these populations by manual gating, as well as the reproducibility of our panels on mouse spleen and whole blood. As a proof-of-principle of the usefulness of our general approach, we also report segment- and life stage-specific patterns of immune cell profiles in the colon. Overall, our data indicate that mechanical dissociation is more suitable and efficient than enzymatic methods for recovering immune cells from all colon layers at once. Additionally, our panels will provide researchers with a relatively simple tool for detailed immune cell profiling in the murine gastrointestinal tract, regardless of life stage or experimental conditions.

Early survival in Atlantic salmon is associated with parental genotypes at loci linked to timing of maturation.

Large effects loci often contain genes with critical developmental functions with potentially broad effects across life-stages. However, the life-stage-specific fitness consequences are rarely explored. In Atlantic salmon, variation in two large-effect loci, six6 and vgll3, is linked to age at maturity, and several physiological and behavioural traits in early life. By genotyping the progeny of wild Atlantic salmon that were planted into natural streams with nutrient manipulations, we tested if genetic variation in these loci is associated with survival in early life. We found that higher early life survival was linked to the genotype associated with late maturation in the vgll3, but with early maturation in the six6 locus. These effects were significant in high-nutrient, but not in in low-nutrient streams. The differences in early survival were not explained by additive genetic effects in the offspring generation, but by maternal genotypes in the six6 locus, and by both parents' genotypes in the vgll3 locus. Our results suggest that indirect genetic effects by large-effect loci can be significant determinants of offspring fitness. This study demonstrates an intriguing case of how large-effect loci can exhibit complex fitness associations across life stages in the wild and indicates that predicting evolutionary dynamics is difficult.

A biofloc system avoids the adverse effects of diets with suboptimal protein levels on zootechnical performance, intestinal histomorphometry, and protein metabolism of Nile tilapia juvenile fed Spirulina biomass (Arthrospira platensis) as an alternative protein source.

This study aimed to evaluate the effect of the biofloc technology (BFT) system and the replacement of fish meal with Spirulina biomass on productive performance, intestinal histomorphometry, plasma biochemistry, and oxidative stress of Nile tilapia juveniles (Oreochromis niloticus) fed suboptimal levels of protein. Two factors were evaluated: production systems (clear water × BFT) and replacement of fish meal with Spirulina (0, 33, 66 e 100%). The design was in a 2 × 4 randomized factorial scheme with four replications, and the fish were evaluated for 48days. Four isoproteic (28% crude protein) diets were formulated with gross energy values close to 4300kcalkg-1. Nile tilapia juveniles (0.23 ± 0.01g) were distributed in 16 circular tanks (70 L) at seven fish/tank. The diets were formulated with protein levels approximately 20% below that required for the species and life stage. No interaction was observed between the factors evaluated (production systems × Spirulina inclusion). Rearing the fish in the BFT system avoided the adverse effects of diets with suboptimal protein levels on performance, intestinal histomorphometry, and protein metabolism. Lower values lower lipid peroxidation and higher antioxidant capacity were observed in fish reared in the BFT system, showing evidence of improvements in antioxidant responses and lower levels of physiological oxidative stress. Spirulina completely replaced fish meal in the diets of Nile tilapia juveniles without adverse effects on intestinal morphometry, protein metabolism, and antioxidant response. Replacing 66% of fish meal with Spirulina improved the productive performance, regardless of the rearing system.

The gut metabolome in a cohort of pregnant and lactating women from Antioquia-Colombia

Nutrition during the perinatal period is an essential component of health and one that can severely impact the correct development of a human being and its overall condition, in all the subsequent stages of life. The availability of several compounds, mainly macronutrients and micronutrients, plays a key role in the balanced nutrition of both mother and baby and is a process with direct relation to the gut microbiome. Thus, we hereby refer to the set of small molecules derived from gut microbiome metabolism as the gut metabolome. These continuous processes occurring in the gut of a gestating or lactating mother related to microbial communities and nutrients, can be revealed by metabolomics. In this study, we explore for the first time the gut metabolome of pregnant and lactating women, from our region of Antioquia-Colombia, applying untargeted metabolomics by LC-QTOF-MS, and molecular networking. Regarding the gut metabolome composition of the cohort, we found, key metabolites that can be used as biomarkers of microbiome function, overall metabolic health, dietary intake, pharmacology, and lifestyle. In our cohort, pregnant women evidenced a significantly higher abundance of prostaglandins, alkaloids, corticosteroids, organosilicons, and natural toxins, while in lactating women, lipids stand out. Our results suggest that unveiling the metabolic phenotype of the gut microbiome of an individual, by untargeted metabolomics, allows a broad visualization of the chemical space present in this important niche and enables the recognition of influential indicators of the host’s health status and habits, especially of women during this significant perinatal period. This study constitutes the first evidence of the use of untargeted LC-QTOF-MS coupled with molecular networking analysis, of the gut microbiome in a Colombian cohort and establishes a methodology for finding relative abundances of key metabolites, with potential use in nutritional and physiological state assessments, for future personalized health and nutrition practices.

A commentary on studies of brain iron accumulation during ageing.

Brain iron content is widely reported to increase during "ageing", across multiple species from nematodes, rodents (mice and rats) and humans. Given the redox-active properties of iron, there has been a large research focus on iron-mediated oxidative stress as a contributor to tissue damage during natural ageing, and also as a risk factor for neurodegenerative disease. Surprisingly, however, the majority of published studies have not investigated brain iron homeostasis during the biological time period of senescence, and thus knowledge of how brain homeostasis changes during this critical stage of life largely remains unknown. This commentary examines the literature published on the topic of brain iron homeostasis during ageing, providing a critique on limitations of currently used experimental designs. The commentary also aims to highlight that although much research attention has been given to iron accumulation or iron overload as a pathological feature of ageing, there is evidence to support functional iron deficiency may exist, and this should not be overlooked in studies of ageing or neurodegenerative disease.

Otolith chemistry reveals ontogenetic movement of the Antarctic toothfish (Dissostichus mawsoni) in the Amundsen Sea polynya, Antarctica

The Amundsen Sea polynya is one of the richest areas of primary productivity in Antarctica. The Antarctic toothfish (Dissostichus mawsoni, TOA) is a commercially valuable circum-Antarctic fish that undertakes ontogenetic movements on the continental shelf. However, the movement and distribution of this species remain unclear in the polynya, especially in the data-poor Amundsen Sea polynya. Along with hydrological and fishery survey data in the Amundsen Sea polynya, the otolith chemistry of TOA from three areas along the ice shelf of the Dotson–Getz Trough was analyzed to explore the movement pattern of this species. The elemental composition deposited during early life in the otolith core did not show significant differences, indicating that TOA in the Amundsen Sea polynya probably experienced a similar hydrological environment at the early life stage or might originate from the same spawning ground. However, the elemental composition deposited at the otolith edge showed that SrCa−1 and LiCa−1 differ in otolith chemistry between areas along the Amundsen Sea coast. In conjunction with additional data from the fish sampled in these areas, this study reveals that TOA show an ontogenetic movement from westward along the ice shelf in the Amundsen Sea polynya. A deeper area (with a depth of over 1000 m) in the west box provides a fish pool for TOA, which needs to be conserved in the fishery management of toothfish populations.

Traffic Noise Impacts Glucocorticoid Response, Activity, and Growth in Two Species of Tadpoles.

There is a large body of evidence linking increased noise to negative health effects for animals. Anthropogenic noise induces behavioral and physiological reactions across a range of taxa and increased traffic noise affects glucocorticoid (GC) hormones associated with the stress response in amphibians. GCs help to maintain homeostasis while balancing energetic tradeoffs between reproduction, growth, and activity. Stressors during early development can impact fitness at later life stages. We measured growth, activity, and GCs in response to high levels of traffic noise in two tadpole species that differ in life-history: Acris crepitans and Rana berlandieri. We predicted earlier exposures to traffic noise will slow development and alter behavior and GC concentrations differently than later exposures. Subjects were initially either exposed to natural levels of traffic noise for 8 days (early exposure) or a white noise control (later exposure), then the treatment was switched. Activity was measured via focal sampling and tadpoles were categorized as active if movement was detected. Tadpoles exposed to white noise initially maintained mass and activity throughout the experiment and early exposure to traffic noise had a greater impact on mass, activity, and GCs. Tadpoles exposed to traffic noise initially lost mass, with A. crepitans regaining mass but not R. berlandieri. When exposed earlier to traffic noise, R. berlandieri increased movement when shifted to the white noise treatment while A. crepitans did not significantly change activity. A. creptians had higher corticosterone release rates compared to R. berlandieri, and in both species, release rates were higher for tadpoles exposed to noise earlier. The longer-lived R. berlandieri allocated more of their energetic resources into activity while the shorter-lived A. crepitans allocated energy towards growth. R. berlandieri and A. crepitans utilized different coping strategies to contend with early exposure to traffic noise, potentially due to differences in life histories. Our findings suggest that these tadpoles employ different coping mechanisms to modulate stress responses in noise-polluted environments, and these mechanisms could influence their fitness later in life. Further study is needed to understand the impact in more sensitive tadpole species.

Predictors of male loneliness across life stages: an Australian study of longitudinal data

BackgroundDespite growing recognition of loneliness as a global public health concern, research on its occurrence and precipitants among men across different life stages remains limited and inconclusive. This study aims to address this gap by investigating the prevalence and predictors of loneliness among a large, representative data set of Australian adult men.MethodsThe study used longitudinal data from waves 2–21 of the Household, Income and Labour Dynamics in Australia (HILDA) Survey, including men aged 15–98. Estimating linear fixed effects regressions that account for unobserved time-invariant individual heterogeneity, a single-item measure of loneliness was regressed on a set of selected explanatory variables over different parts of the life course.ResultsIncreased social isolation, romantic partnership dissolution, having a long-term disability, and stronger beliefs that the man, rather than the woman, should be the breadwinner of the household, are associated with greater loneliness. Frequent social connection, having a romantic partner, and high neighbourhood satisfaction are protective against loneliness. The findings also reveal several differences in the predictors of loneliness over the life course. Job security is especially important for younger men, whereas for older men volunteering and less conservative gender role attitudes are important factors that can decrease loneliness.ConclusionsThe results emphasise the need to consider age-specific factors and societal expectations in understanding and addressing loneliness amongst men. Additionally, the findings underscore the importance of raising awareness about the impact of societal norms and expectations on men's mental health. The results offer valuable insights for policymakers, healthcare providers, and researchers to develop effective strategies and support systems to combat loneliness and promote well-being among men.

Residential mobility and suicide in Belgium

Using Belgian administrative datasets (National Register, Census, and death certificates) on individuals aged 20–64 (N=7,246,740 individuals and 4,109 suicides), the study examined the association between mobility and suicide in the context of union transitions and different life stages. Using Cox proportional hazard models, we found that, in general, moving was associated with an increased risk of suicide than immobility, except for moves in the context of union transitions. Additionally, results highlighted that union dissolutions were associated with a higher risk of suicide – regardless of residential mobility. Moreover, mobility (compared to immobility) for individuals who were in stable situations (single or partnered) or who were in their mid-adulthood was associated with higher risks of suicide. Finally, middle-aged adults (aged 40–54) presented higher suicide risks in all cases of residential mobility, including if accompanied by union transitions.

N-Heterocycles as Promising Antiviral Agents: A Comprehensive Overview

Viruses are a real threat to every organism at any stage of life leading to extensive infections and casualties. N-heterocycles can affect the viral life cycle at many points, including viral entrance into host cells, viral genome replication, and the production of novel viral species. Certain N-heterocycles can also stimulate the host’s immune system, producing antiviral cytokines and chemokines that can stop the reproduction of viruses. This review focused on recent five- or six-membered synthetic N-heterocyclic molecules showing antiviral activity through SAR analyses. The review will assist in identifying robust scaffolds that might be utilized to create effective antiviral drugs with either no or few side effects.

The Role of Life Stages in the Sensitivity of Hediste diversicolor to Nanoplastics: A Case Study with Poly(Methyl)Methacrylate (PMMA)

The presence of plastic particles in oceans has been recognized as a major environmental concern. The decrease in particle size increases their ability to directly interact with biota, with particles in the nanometer size range (nanoplastics—NPs) displaying a higher ability to penetrate biological membranes, which increases with the decrease in particle size. This study aimed to evaluate the role of life stages in the effects of poly(methyl)methacrylate (PMMA) NPs on the polychaete Hediste diversicolor, a key species in the marine food web and nutrient cycle. Thus, behavioral (burrowing activity in clean and spiked sediment) and biochemical endpoints (neurotransmission, energy reserves, antioxidant defenses, and oxidative damage) were assessed in juvenile and adult organisms after 10 days of exposure to spiked sediment (between 0.5 and 128 mg PMMA NPs/Kg sediment). Overall, the results show that H. diversicolor is sensitive to the presence of PMMA NPs. In juveniles, exposed organisms took longer to burrow in sediment, with significant differences from the controls being observed at all tested concentrations when the test was performed with clean sediment, whereas in PMMA NP-spiked sediment, effects were only found at the concentrations 8, 32, and 128 mg PMMA NPs/Kg sediment. Adults displayed lower sensitivity, with differences to controls being found, for both sediment types, at 8, 32, and 128 mg PMMA NPs/Kg sediment. In terms of Acetylcholinesterase, used as a marker of effects on neurotransmission, juveniles and adults displayed opposite trends, with exposed juveniles displaying increased activity (suggesting apoptosis), whereas in adults, overall decreased activity was found. Energy-related parameters revealed a generally similar pattern (increase in exposed organisms) and higher sensitivity in juveniles (significant effects even at the lower concentrations). NPs also demonstrated the ability to increase antioxidant defenses (higher in juveniles), with oxidative damage only being found in terms of protein carbonylation (all tested NPs conditions) in juveniles. Overall, the data reveal the potential of PMMA NPs to affect behavior and induce toxic effects in H. diversicolor, with greater effects in juveniles.

Habitat persistency analysis with HEM‐PEAK: A novel approach for the assessment of hydropeaking impacts and mitigation measure design

AbstractHydropeaking is one of the most severe pressures of hydropower on aquatic ecosystems. The discharge fluctuations due to turbine operations cause frequent shifts in hydraulic habitat characteristics such as flow velocity and water depth. Those rapid changes on a daily or sub daily basis, however, are beyond the possibilities of evolutionary adaptations of aquatic organisms, especially for fish in their sensitive early life stages. Thus, one central aim in terms of the evaluation of hydropeaking impacts or the design of mitigation measures is the analysis or establishment of hydraulically stable habitat conditions. This study presents a novel habitat assessment tool to quantify hydraulically stable habitat conditions in the form of a persistency of suitable habitats in hydropeaking reaches. The HEM‐PEAK tool determines areas that contain equal ranges of depth‐averaged flow velocity and water depth for both base flow and peak flow in three categories. Those areas also exclude dewatering sites, which have to be seen as ‘residual risk for stranding’. In the present study, the model was used to evaluate the YOY habitats of brown trout and grayling. The model was tested for 14 hydropeaking reaches to evaluate the quantity of habitat persistency for different morphological characteristics, such as straight, winding, alternating gravel bars and bifurcation reaches. The findings reveal that there is no relationship between hydraulically stable habitat conditions with reach scale bed slope or the magnitude of dewatering areas. However, the changes in specific discharge in relation to bankfull width could be negatively related to the magnitude of hydraulically stable habitat conditions independent of the morphological type. This relationship is minor for summer scenarios compared to spring, as the initial habitat quality during the increased base flow conditions is already limiting the availability of suitable habitats which might have persistency during peak flow. In detail, several self‐forming bars like point bars and artificial structures like groins and coarse rip‐rap could be determined, which could be explicitly addressed in terms of mitigation measure design based on the application of the HEM‐PEAK tool.

Methane output across life stages in sheep, how it differs from lambs to adult ewes using portable accumulation chambers.

Methane (CH4) produced from enteric fermentation is a potent greenhouse gas produced by ruminant animals. Multiple measurements are required across life stages to develop an understanding of how CH4 output changes throughout the animal's lifetime. The objectives of the current study were to estimate CH4 output across life stages in sheep and to investigate the relationship between CH4 output and dry matter intake (DMI). Data were generated on a total of 266 female Suffolk and Texel animals. Methane and carbon dioxide (CO2) output, estimated using portable accumulation chambers, and DMI, estimated using the n-alkane technique outdoors and using individual penning indoors, were quantified across the animal's life stage; as lambs (< 12 months), nulliparous hoggets (12 to 24 months) and ewes (primiparous or greater; > 24 months). Ewes were further classified as pregnant, lactating and dry (non-pregnant and non-lactating). Multiple measurements were taken within and across life stages on the same animals. A linear mixed model was used to determine if CH4 and CO2 output differed across life stages and using a separate linear mixed model the factors associated with CH4 output within each life stage were also investigated. Methane, CO2 output and DMI differed by life stage (P<0.05), with lactating ewes producing the greatest amount of CH4 (25.99g CH4/day) and CO2 (1711.6g CO2/day), while also having the highest DMI (2.18kg dry matter/day). Methane output differed by live-weight of the animals across all life stages (P<0.001). As ewe body condition score increased CH4 output declined (P<0.05). Correlations between CH4 output measured across life stages ranged from 0.26 (SE 0.08; lambs and lactating ewes) to 0.59 (SE 0.06; hoggets and pregnant ewes), while correlations between CO2 output measured across life stages ranged from 0.12 (SE 0.06; lambs and hoggets) to 0.65 (SE 0.06; hoggets and lactating ewes). Dry matter intake was moderately correlated with CH4 (0.44; SE 0.04) and CO2 output (0.59; SE 0.03). Results from this study provide estimates of CH4 output across life stages in a pasture-based sheep production system and offer valuable information for the national inventory and the marginal abatement cost curve on the optimum time to target mitigation strategies.

Development and validation of an innovative headspace collection technique: volatile organic compound patterns emitted by different developmental stages of Halyomorpha halys

Over the past two decades, several headspace collection techniques have been used to detect and identify volatile organic compounds (VOCs) emitted by plants, pests, air, and soil. Volatiles emitted by pests and infected plants are usually found at low concentrations. The important challenge is to be able to capture an exact collection of relative quantities of the relevant VOCs. Here we present an innovative headspace collecting device (HSCD) for sampling VOCs, which ensures an exact regulation of mass flow velocity and collected total gas volume allowing besides qualitative analysis of collected VOCs, an exact comparison of their relative quantities in plant or insect headspace samples. The HSCD possess six parallel odor collection systems each consisting of a digital mass flow detector and controller connected to a vacuum pump, which are mounted in a trolley suitcase, connected by tubes, and wired electrically. The programming of the channels, can be done by a digital control unit. Using the HSCD, VOCs emitted by the brown marmorated stink bug (BMSB), Halyomorpha halys, from its different developmental stages including egg, nymphal stages, nymphal exuvia, and adults were collected on thermal desorption tubes and analyzed using an automated thermal desorber connected to a gas chromatography-mass spectrometry system. Forty-five VOCs were identified in total, which mainly consisted of tridecane (4.36-69.33%), E-2-decenal (4.24-26.48%), 2-undecenal (0.63-50.03%), and E-4-oxo-2-hexenal (1.22-20.58%). The random forest analysis revealed three different chemical patterns among BMSB life stages samples. In conclusion, these results indicate that the new developed HSCD, a mobile, easy to use, and reliable instrument, has a high potential to sample relevant VOCs of a specific life stage of an insect both qualitatively and quantitatively. It was demonstrated that this information can be used for identifying specific chemical signatures, which fit to specific life stages of the BMSB, and may be used as biomarker for on-site detection of this pest e.g. in shipping containers or agricultural areas.

Identifying impactful sea turtle conservation strategies: a mismatch between most influential and most readily manageable life-stages

Sea turtles worldwide face a range of threats including sea level rise and warming associated with climate change, predation by invasive species, plastic and light pollution, coastal development, and human interference. Conservation managers have a long history of aiding sea turtle populations, from protecting nests to head-starting hatchlings. Due to these challenges faced by turtles, there is a constant focus on assessing the likely success of proposed conservation interventions to help inform decision-making processes. We develop an age-based, spatially implicit population model for the north-west shelf stock of Australia’s endemic flatback turtle Natator depressus that estimates the long-term outcomes of a range of onshore and offshore conservation interventions. Analysis of the model shows that young adults contribute most to population growth (i.e. have highest expected future reproductive success); however, this is often the most difficult life stage to manipulate in the field. Observable outcomes of interventions are often delayed for many years, especially for on shore activities (e.g. protecting eggs and hatchlings), due to late age to maturity. The potential impact of warming-induced female bias on population dynamics was also investigated. Although such bias increases population growth rates in the short term, negative effects of the bias (e.g. reduced female mating success) and negative environmental effects (e.g. reduced survival rates, habitat loss) can lead to sustained declines. Population models can rapidly assess climate change and conservation impacts on turtle dynamics and can guide monitoring efforts for real-world application.

Flow-through imaging and automated analysis of oil-exposed early stage Atlantic cod (Gadus morhua)

Toxicology studies in early fish life stages serve an important function in measuring the impact of potentially harmful substances, such as crude oil, on marine life. Morphometric analysis of larvae can reveal the effects of such substances in retarding growth and development. These studies are labor intensive and time consuming, typically resulting in only a small number of samples being considered. An automated system for imaging and measurement of experimental animals, using flow-through imaging and an artificial neural network to allow faster sampling of more individuals, has been described previously and used in toxicity experiments. This study compares the performance of the automated imaging and analysis system with traditional microscopy techniques in measuring biologically relevant endpoints using two oil treatments as positive controls. We demonstrate that while the automated system typically underestimates morphometric measurements relative to analysis of manual microscopy images, it shows similar statistical results to the manual method when comparing treatments across most endpoints. It allows for many more individual specimens to be sampled in a shorter time period, reducing labor requirements and improving statistical power in such studies, and is noninvasive allowing for repeated sampling of the same population.

Using multi‐scale spatial models of dendritic ecosystems to infer abundance of a stream salmonid

Abstract Understanding patterns of species abundance is essential for planning landscape‐level conservation. The complex hierarchies of dendritic ecosystems result in different levels of heterogeneity at distinct geographic scales. Species responses to dynamic environmental drivers may also vary spatially depending on their interactions with landscape features. Monitoring abundance by explicitly quantifying their spatial and temporal variation is important for strategic management. We analysed brook trout (Salvelinus fontinalis) count data collected from 173 sites in western North Carolina between 1989 and 2015. We developed a Bayesian hierarchical model that used single‐ and multi‐pass electro‐fishing data and characterized their respective capture probabilities. We quantified spatial variation using a multi‐scale process model representative of the nested stream habitats, and we investigated differences in population temporal trends and responses to seasonal weather patterns by space and life stage. Trout abundance was lower on the Atlantic slope of the Eastern Continental Divide than in the interior, on average, and the Atlantic slope juveniles were more adversely affected by high winter flows. However, Atlantic slope populations of both lifestages demonstrated positive temporal trends, whereas Interior juveniles demonstrated a negative trend. We found higher spatial variation than temporal variation in abundance when conditioned on the covariates, where the primary source of spatial heterogeneity was revealed at the segment level, compared to watershed or network levels. Our multi‐scale spatial model outperformed simpler models in abundance estimation and out‐of‐sample prediction. The inferred per‐pass capture probabilities indicated that single‐pass surveys were as efficient as multi‐pass surveys. Synthesis and applications. Our study suggested conservation priority should involve multiple criteria, including present‐day abundance, temporal trend and sensitivity to environmental drivers. Based on the inferred scale‐specific variations in trout abundance, we recommend that future surveys strategically combine single‐pass surveys with multi‐pass surveys to optimize abundance estimation. Our approach is widely applicable to other species and ecosystems occupying dendritic habitats.

The effects of exposure to and timing of a choline-deficient diet during pregnancy and early postnatal life on the skeletal muscle transcriptome of the offspring

Nonalcoholic fatty liver disease (NAFLD) is related to muscle loss, but the precise mechanism underlying this association remains unclear. The aim of the present study was thus to determine the influence of maternal fatty liver and dietary choline deficiency during pregnancy and/or lactation periods on the skeletal muscle gene expression profile among 24-day-old male rat offspring. Histological examination of skeletal muscle tissue specimens obtained from offspring of dams suffering from fatty liver, provided with proper choline intake during pregnancy and lactation (NN), fed a choline-deficient diet during both periods (DD), deprived of choline only during pregnancy (DN), or only during lactation (ND), was performed. The global transcriptome pattern was assessed using a microarray approach (Affymetrix® Rat Gene 2.1 ST Array Strip). The relative expression of selected genes was validated by real-time PCR (qPCR). Morphological differences in fat accumulation in skeletal muscle related to choline supply were observed. The global gene expression profile was consistent with abnormal morphological changes. Mettl21c gene was overexpressed in all choline-deficient groups compared to the NN group, while two genes, Cdkn1a and S100a4, were downregulated. Processes of protein biosynthesis were upregulated, and processes related to cell proliferation and lipid metabolism were inhibited in DD, DN, and ND groups compared to the NN group. Prenatal and early postnatal exposure to fatty liver and dietary choline deficiency leads to changes in the transcriptome profile in skeletal muscle of 24-day old male rat offspring and is associated with muscle damage, but the mechanism of it seems to be different at different developmental stages of life. Adequate choline intake during pregnancy and lactation can prevent severe muscle disturbance in the progeny of females suffering from fatty liver.

Effectiveness and cost-effectiveness of a 12-month automated text message intervention for weight management in postpartum women with overweight or obesity: protocol for the Supporting MumS (SMS) multisite, parallel-group, randomised controlled trial

IntroductionThe reproductive years can increase women’s weight-related risk. Evidence for effective postpartum weight management interventions is lacking and engaging women during this life stage is challenging. Following a promising pilot...

The beginning of becoming a human.

According to birth certificates, the life of a child begins once their body comes out of the mother's womb. But when does their organismal life begin? Science holds a palette of answers-depending on how one defines a human life. In 1984, a commission on the regulatory framework for human embryo experimentation opted not to answer this question, instead setting a boundary, 14 days post-fertilization, beyond which any experiments were forbidden. Recently, as the reproductive technologies developed and the demand for experimentation grew stronger, this boundary may be set aside leaving the ultimate decision to local oversight committees. While science has not come closer to setting a zero point for human life, there has been significant progress in our understanding of early mammalian embryogenesis. It has become clear that the 14-day stage does in fact possess features, which make it a foundational time point for a developing human. Importantly, this stage defines the separation of soma from the germline and marks the boundary between rejuvenation and aging. We explore how different levels of life organization emerge during human development and suggest a new meaning for the 14-day stage in organismal life that is grounded in recent mechanistic advances and insights from aging studies.