Project description:Obesity poses a public health threat, reaching epidemic proportions. Our hypothesis suggests that some of this epidemic stems from its transmission across generations via paternal epigenetic mechanisms. To investigate this possibility, we focused on examining the paternal transmission of CpG methylation. First-generation male Wistar rats were fed either a high-fat diet (HF) or chow and were mated with females fed chow. We collected sperm from these males. The resulting offspring were raised on a chow diet until day 35, after which they underwent a dietary challenge. Diet-induced obese (DIO) male rats passed on the obesogenic trait to both male and female offspring. We observed significant hypermethylation of the Pomc promoter in the sperm of HF-treated males and in the hypothalamic arcuate nucleus (Arc) of their offspring at weaning. However, these differences in Arc methylation decreased later in life. This hypermethylation is correlated with increased expression of DNMT3B. Further investigating genes in the Arc that might be involved in obesogenic transgenerational transmission, using reduced representation bisulfite sequencing (RRBS) we identified 77 differentially methylated regions (DMRs), highlighting pathways associated with neuronal development. These findings support paternal CpG methylation as a mechanism for transmitting obesogenic traits across generations.
Project description:To investigate the mechanism by which paternal exposure to high-fat diet (HFD) exacerbates environmental stress-impaired testicular germ cell development in offspring, testicular RNA sequencing was performed in H+Cd (the offspring were treated with Cd after paternal exposure to one-generational HFD) and H+H+Cd (the offspring were treated with Cd after paternal exposure to bi-generational HFD) groups. Compared with HFD1D group and HFD2D group, 229 mRNAs were upregulated and 268 mRNAs were downregulated, screened for a 1.2-fold change and adjusted with P < 0.05. GO analysis revealed that downregulated mRNAs were related to multiple biological processes, including the "retinol metabolic process," the "reproductive process," and the "spermatogenesis".
Project description:In this study, we aimed to find out how the sperm tsRNA involved in paternal high-fat diet induced abnormal gluconeogenesis of F1 offspring, and explore the underlying molecular mechanism of its regulation.
Project description:<p>The gut microbiota operates at the interface of host-environment interactions to influence human homeostasis and metabolic networks. Environmental factors that unbalance gut microbial ecosystems can therefore elicit physiological and disease-associated responses across somatic tissues. However, the systemic impact of the gut microbiome on the germline - and consequently on the F1 offspring it gives rise to - is unexplored. Here we show that the gut microbiota act as a key interface between paternal preconception environment and intergenerational health in mice. Perturbations to the gut microbiota of prospective fathers increase the probability of their offspring presenting with low birth weight, severe growth restriction and premature mortality. Transmission of disease risk occurs via the germline and is provoked by pervasive gut microbiome perturbations, including non-absorbable antibiotics or osmotic laxatives, but is rescued by restoring the paternal microbiota before conception. This effect is linked with a dynamic response to induced dysbiosis in the male reproductive system, including impaired leptin signalling, altered testicular metabolite profiles and remapped small RNA payloads in sperm. As a result, dysbiotic fathers trigger an elevated risk of in utero placental insufficiency, revealing a placental origin of mammalian intergenerational effects. Our study defines a regulatory ‘gut-germline axis’ in males, which is sensitive to environmental exposures and programs offspring fitness through impacting placental function.</p>
Project description:Many acquired traits related to fat metabolism are inherited, and nutritional factors can induce fatty liver in chickens. We found that the paternal fatty livers induced by high-fat diet in Jingxing-Huang chickens were inherited, but the molecular mechanisms of inherited fatty liver in chickens are far from clear. The goals of this study are to compare liver transcriptome profiling (RNA-seq) in F1 generation to screen candidate genes for acquired fatty liver. Compared to birds without fatty liver in the control group, the paternal group exhibited altered hepatic gene expression profiles, including up-regulation of several key genes involved in fatty acid metabolism, lipid metabolism and glucose metabolism (ACACA, FASN, SCD, ACSL5, FADS2, FABP1, APOA4 and ME1). This study uniquely revealed that acquired fatty liver in cocks can be inherited. The hepatic gene expression profiles were altered in chickens with the inherited phenotype of acquired paternal fatty liver and several genes could be candidate biomarkers.
Project description:The global rise in obesity has revitalized a search to understand genetic, and in particular, epigenetic factors underlying the disease. We present a Drosophila model of paternal-diet-induced Inter-Generational Metabolic Reprogramming (IGMR) and identify genes required for its encoding in offspring. Intriguingly, we find that as little as two days of dietary intervention in fathers elicits obesity in offspring. Paternal sugar acts as a physiological suppressor of variegation, de-silencing chromatin state-defined transcriptional units in both mature sperm and in offspring embryos. We identify requirements for H3K9/K27me3 dependent reprogramming of metabolic genes in two distinct germline and zygotic windows. Critically, we find evidence that a similar system regulates obesity-susceptibility and phenotype variation in mice and humans. The findings provide insight into the mechanisms underlying intergenerational metabolic reprogramming and carry profound implications for our understanding of phenotypic variation and evolution. RNA-seq on Drosophila embryos and sperm samples fed medium and high sugar.
Project description:The increase in high-energy dietary intakes is a well-known risk factor for many diseases, and can also negatively impact the tendon. Ancestral lifestyle can mitigate the metabolic harmful effects of offspring exposed to high-fat diet (HF). However, the influence of paternal exercise on molecular pathways associated to offspring tendon remodeling remains to be determined. We investigated the effects of 8 weeks of paternal resistance training (RT) on offspring tendon proteome exposed to standard diet or HF diet. Wistar rats were randomly divided into two groups: sedentary fathers and trained fathers (8 weeks, three times per week, with 8-12 dynamic movements per climb in a stair climbing apparatus). The offspring were obtained by mating with sedentary females. Upon weaning, male offspring were divided into four groups (five animals per group): offspring from sedentary fathers were exposed either to control diet (SFO-C), or to high-fat diet (SFO-HF); offspring from trained fathers were exposed to control diet (TFO-C) or to a high-fat diet (TFO-HF). The Nano-LC-MS/MS analysis revealed 383 regulated proteins among offspring groups. HF diet induced a decrease of abundance in tendon proteins related to extracellular matrix organization, transport, immune response and translation. On the other hand, the changes in the offspring tendon proteome in response to paternal RT were more pronounced when the offspring were exposed to HF diet, resulting in positive regulation of proteins essential for the maintenance of tendon integrity. Most of the modulated proteins are associated to biological pathways related to tendon protection and damage recovery, such as extracellular matrix organization and transport. The present study demonstrated that the father's lifestyle could be crucial for tendon homeostasis in the first generation. Our results provide important insights into the molecular mechanisms involved in paternal intergenerational effects and potential protective outcomes of paternal RT.
Project description:Several studies have described phenotypic changes in the offspring of mice exposed to a variety of environmental factors, including diet, toxins, and stress; however, the molecular pathways involved in these changes remain unclear. Using a high fat diet (HFD)-induced obesity mouse model, we examined liver gene expression in male offspring and analyzed chromatin of paternal spermatozoa. We found that the hepatic mRNA level of 7 genes (out of 20 evaluated) was significantly altered in HFD male offspring compared to control mice, suggesting that phenotypic changes in the offspring depend on parental diet. We examined 7 imprinted loci in spermatozoa DNA from HFD-treated and control fathers by bisulfite sequencing, but did not detect changes in DNA methylation associated with HFD. Using chromatin immunoprecipitation followed by high-throughput sequencing, we found differential histone H3-occupancy at genes involved in the regulation of embryogenesis and differential H3K4me1-enrichment at transcription regulatory genes in HFD fathers vs. control mice. These results suggest that dietary exposure can modulate histone composition at regulatory genes implicated in developmental processes.
Project description:The global rise in obesity has revitalized a search to understand genetic, and in particular, epigenetic factors underlying the disease. We present a Drosophila model of paternal-diet-induced Inter-Generational Metabolic Reprogramming (IGMR) and identify genes required for its encoding in offspring. Intriguingly, we find that as little as two days of dietary intervention in fathers elicits obesity in offspring. Paternal sugar acts as a physiological suppressor of variegation, de-silencing chromatin state-defined transcriptional units in both mature sperm and in offspring embryos. We identify requirements for H3K9/K27me3 dependent reprogramming of metabolic genes in two distinct germline and zygotic windows. Critically, we find evidence that a similar system regulates obesity-susceptibility and phenotype variation in mice and humans. The findings provide insight into the mechanisms underlying intergenerational metabolic reprogramming and carry profound implications for our understanding of phenotypic variation and evolution.