Large offspring syndrome (LOS) refers to an overgrowth phenotype sometimes observed in cattle fetuses and newborns produced by the use of assisted reproductive technologies (ART). This chapter discusses the current knowledge on ART-induced abnormal offspring syndrome (AOS). It also discusses findings from sheep as AOS has also been documented in this species, and from Beckwith–Wiedemann syndrome (BWS), a human congenital overgrowth condition which phenocopies AOS. In addition, the chapter presents evidence of spontaneous AOS in cattle and provides examples of financial loss incurred by the cattle industry as a result of this syndrome. As the causes of BWS at the molecular level have been largely attributed to epigenetic defects, which include alterations of DNA methylation and loss-of-imprinting, it discusses these epigenetic modifications/mechanisms. Early identification of AOS would allow early elective termination of the pregnancy in order to prevent the monetary losses and animal welfare concerns associated with AOS.
Beckwith-Wiedemann syndrome (BWS) is the most common epigenetic overgrowth syndrome, caused by epigenetic alterations on chromosome 11p15. In ∼50% of patients with BWS, the imprinted region KvDMR1 (IC2) is hypomethylated. Nearly, all children with BWS develop organ overgrowth and up to 28% develop cancer during childhood. The global epigenetic alterations beyond the 11p15 region in BWS are not currently known. Uncovering these alterations at the methylome, transcriptome, and chromatin architecture levels are necessary steps to improve the diagnosis and understanding of patients with BWS. Here, we characterized the complete epigenetic profiles of BWS IC2 individuals together with the animal model of BWS, bovine large offspring syndrome (LOS). A novel finding of this research is the identification of two molecular subgroups of BWS IC2 individuals. Genome-wide alterations were detected for DNA methylation, transcript abundance, alternative splicing events of RNA, chromosome compartments, and topologically associating domains (TADs) in BWS and LOS, with shared alterations identified between species. Altered chromosome compartments and TADs were correlated with differentially expressed genes in BWS and LOS. Together, we highlight genes and genomic regions that have the potential to serve as targets for biomarker development to improve current molecular diagnostic methodologies for BWS.
Beckwith-Wiedemann Syndrome (BWS) is the most common epigenetic overgrowth syndrome, caused by epigenetic alterations on chromosome 11p15. In ∼50% of patients with BWS, the imprinted region KvDMR1 (IC2) is hypomethylated. Nearly all children with BWS develop organ overgrowth and up to 28% develop cancer during childhood. The global epigenetic alterations beyond the 11p15 region in BWS are not currently known. Uncovering these alterations at the methylome, transcriptome, and chromatin architecture levels are necessary steps to improve the diagnosis and understanding of patients with BWS. Here we characterized the complete epigenetic profiles of BWS IC2 individuals together with the animal model of BWS, bovine large offspring syndrome (LOS). A novel finding of this research is the identification of two molecular subgroups of BWS IC2 individuals. Genome-wide alternations were detected for DNA methylation, transcript abundance, alternative splicing events of RNA, chromosome compartments, and topologically associating domains (TADs) in BWS and LOS, with shared alterations identified between species. Altered chromosome compartments and TADs were correlated with differentially expressed genes in BWS and LOS. Together, we highlight genes and genomic regions that have the potential to serve as targets for biomarker development to improve current molecular diagnostic methodologies for BWS.
Unlike mild DNA damage exposure, DNA damage repair (DDR) is reported to be ineffective in full-grown mammalian oocytes exposed to moderate or severe DNA damage. The underlying mechanisms of this weakened DDR are unknown. Here, we show that moderate DNA damage in full-grown oocytes leads to aneuploidy. Our data reveal that DNA-damaged oocytes have an altered, closed, chromatin state, and suggest that the failure to repair damaged DNA could be due to the inability of DDR proteins to access damaged loci. Our data also demonstrate that, unlike somatic cells, mouse and porcine oocytes fail to activate autophagy in response to DNA double-strand break-inducing treatment, which we suggest may be the cause of the altered chromatin conformation and inefficient DDR. Importantly, autophagy activity is further reduced in maternally aged oocytes (which harbor severe DNA damage), and its induction is correlated with reduced DNA damage in maternally aged oocytes. Our findings provide evidence that reduced autophagy activation contributes to weakened DDR in oocytes, especially in those from aged females, offering new possibilities to improve assisted reproductive therapy in women with compromised oocyte quality. DNA damage repair machinery is not robust in full-grown mammalian oocytes. Here, the authors demonstrate that mammalian oocytes fail to activate autophagy in response to DNA DSBs, correlating with an altered chromatin structure, improper localization of DNA damage repair proteins and increased DNA damage.
Reproduction, Fertility and Development is an international journal publishing original research , review and comment in the fields of reproduction and developmental biology in humans, domestic animals and wildlife
Early embryonic loss, caused by reduced embryo developmental competence, is the major cause of subfertility in humans and animals. This embryo developmental competence is determined during oocyte maturation and the first embryo divisions. Therefore, it is essential to identify the underlying molecules regulating these critical developmental stages. Cathepsin L (CTSL), a lysosomal cysteine protease, is involved in regulating cell cycle progression, proliferation and invasion of different cell types. However, CTSL role in mammalian embryo development is unknown. Using bovine in vitro maturation and culture systems, we show that CTSL is a key regulator for embryo developmental competence. We employed a specific CTSL detection assay in live cells to show that CTSL activity correlates with meiotic progression and early embryo development. Inhibiting CTSL activity during oocyte maturation or early embryo development significantly impaired oocyte and embryo developmental competence as evidenced by lower cleavage, blastocyst and hatched blastocyst rates. Moreover, enhancing CTSL activity, using recombinant CTSL (rCTSL), during oocyte maturation or early embryo development significantly improved oocyte and embryo developmental competence. Importantly, rCTSL supplementation during oocyte maturation and early embryo development significantly improved the developmental competence of heat-shocked oocytes/embryos which are notoriously known for reduced quality. Altogether, these results provide novel evidence that CTSL plays a pivotal role in regulating oocyte meiosis and early embryonic development.
Autism Spectrum Disorder (ASD) has been associated with a complex interplay between genetic and environmental factors. Prenatal stress exposure has been identified as a possible risk factor, although most stress-exposed pregnancies do not result in ASD. The serotonin transporter (SERT) gene has been linked to stress reactivity, and the presence of the SERT short (S)-allele has been shown to mediate the association between maternal stress exposure and ASD. In a mouse model, we investigated the effects of prenatal stress exposure and maternal SERT genotype on offspring behavior and explored its association with maternal microRNA (miRNA) expression during pregnancy. Pregnant female mice were divided into four groups based on genotype (wildtype or SERT heterozygous knockout (Sert-het)) and the presence or absence of chronic variable stress (CVS) during pregnancy. Offspring behavior was assessed at 60 days old (PD60) using the three-chamber test, open field test, elevated plus-maze test, and marble-burying test. We found that the social preference index (SPI) of SERT-het/stress offspring was significantly lower than that of wildtype control offspring, indicating a reduced preference for social interaction on social approach, specifically for males. SERT-het/stress offspring also showed significantly more frequent grooming behavior compared to wildtype controls, specifically for males, suggesting elevated repetitive behavior. We profiled miRNA expression in maternal blood samples collected at embryonic day 21 (E21) and identified three miRNAs (mmu-miR-7684-3p, mmu-miR-5622-3p, mmu-miR-6900-3p) that were differentially expressed in the SERT-het/stress group compared to all other groups. These findings suggest that maternal SERT genotype and prenatal stress exposure interact to influence offspring behavior, and that maternal miRNA expression late in pregnancy may serve as a potential marker of a particular subtype of ASD pathogenesis.
Large/abnormal Offspring Syndrome (LOS/AOS) is a congenital overgrowth condition of cattle and sheep, characterized by macrosomia, abdominal wall defects, organomegaly, difficulty to stand and suckle at parturition. The condition was first described as an exclusive consequence of assisted reproductive technologies, such as in vitro production and somatic cell nuclear transfer (cloning). However, we recently reported the spontaneous occurrence of this syndrome in cattle. The etiology of LOS is unclear, although the syndrome is an epigenetic condition characterized by multi-locus loss-of-imprinting, global dysregulation of small and long RNAs, changes in DNA methylation, and altered chromosomal architecture. These molecular and epigenetic changes affect biological pathways implicated in organ size, cell proliferation, cell survival, resulting in the phenotypes which characterize LOS. The lack of accurate tools for the prediction and diagnosis of LOS and the prevention of dystocia resulting from fetal overgrowth is a major concern for the dairy and beef industries. Furthermore, death of the calf and/or dam during calving adds animal welfare issues and affects the net income of the industry. An early diagnosis of LOS/AOS during gestation is critical to facilitate the decision-making process on whether to allow the pregnancy to continue or not in order to prevent harm to the dam as well as to provide producers with the timely necessary information to prepare for a difficult birth. The present review summarizes the definition, traits, incidence, and molecular characteristics of LOS to provide information and serve as a guide for future investigations regarding the early identification of LOS during pregnancy in cattle.
Background As couples struggle with infertility and livestock producers wish to rapidly improve genetic merit in their herd, assisted reproductive technologies (ART) have become increasingly popular in human medicine as well as the livestock industry. Utilizing ART can cause an increased risk of congenital overgrowth syndromes, such as Large Offspring Syndrome (LOS) in ruminants. A dysregulation of transcripts has been observed in bovine fetuses with LOS, which is suggested to be a cause of the phenotype. Our recent study identified variations in tRNA expression in LOS individuals, leading us to hypothesize that variations in tRNA expression can influence the availability of their processed regulatory products, tRNA-derived fragments (tRFs). Due to their resemblance in size to microRNAs, studies suggest that tRFs target mRNA transcripts and regulate gene expression. Thus, we have sequenced small RNA isolated from skeletal muscle and liver of day 105 bovine fetuses to elucidate the mechanisms contributing to LOS. Moreover, we have utilized our previously generated tRNA sequencing data to analyze the contribution of tRNA availability to tRF abundance. Results 22,289 and 7,737 unique tRFs were predicted in the liver and muscle tissue respectively. The greatest number of reads originated from 5’ tRFs in muscle and 5’ halves in liver. In addition, mitochondrial (MT) and nuclear derived tRF expression was tissue-specific with most MT-tRFs and nuclear tRFs derived from Lys UUU and iMet CAU in muscle, and Asn GUU and Gly GCC in liver. Despite variation in tRF abundance within treatment groups, we identified differentially expressed (DE) tRFs across Control-AI, ART-Normal, and ART-LOS groups with the most DE tRFs between ART-Normal and ART-LOS groups. Many DE tRFs target transcripts enriched in pathways related to growth and development in the muscle and tumor development in the liver. Finally, we found positive correlation coefficients between tRNA availability and tRF expression in muscle (R=0.47) and liver (0.6). Conclusion Our results highlight the dysregulation of tRF expression and its regulatory roles in LOS. These tRFs were found to target both imprinted and non-imprinted genes in muscle as well as genes linked to tumor development in the liver. Furthermore, we found that tRNA transcription is a highly modulated event that plays a part in the biogenesis of tRFs. This study is the first to investigate the relationship between tRNA and tRF expression in combination with ART-induced LOS.
“Companion Animals” is a sophomore level elective in the Division of Animal Sciences at the University of Missouri (MU). This class focuses primarily on dogs, cats, and horses. Topics covered include the pet industry, breeds, wellness, management, care, training, zoonotic diseases, evolution and domestication, toxicology, nutrition, reproduction, genetics, human animal interactions, and biomedical research. As this course is designated a biological science course, several non-majors also enroll in the class each year. What makes this course different from other courses taught in the Division is that it is a “service-learning course.” This means that students volunteer 20-35 hours with non-profits and neighborhood organizations, including the local animal shelter and equine therapy services for persons with disabilities. The partnerships are coordinated by the Office of Service Learning at MU. The benefits for the students include 1) development of professional skills and exploration of possible careers, 2) civic engagement, 3) public service leadership, and 4) understanding of diversity, equity and inclusion. Together, the students in the course perform more >850 hours of community service and their engagement creates >$18,500 of positive economic impact in the state of Missouri. Overall, 93% of MU students would recommend their service experience to a friend. Early in the semester, Dr. Rivera, the course coordinator, meets for 15 minutes with each student to learn about the reason they chose their service, invariably the majority answer, “because of the animals.” Also, at the end of the semester Dr. Rivera meets for 15 minutes with each student to learn about their volunteering experience. When asked “what was the best part of the service?” the vast majority of the students respond “the people.” In conclusion, the general life skills, social conscience, and personal growth that the students attain from their service is not attainable in the typical classroom setting.
In vitro production (IVP) of embryos in cattle can result in large/abnormal offspring syndrome (LOS/AOS) which is characterized by macrosomia. LOS can cause dystocia and lead to the death of dam and calf. Currently, no test exists to identify LOS pregnancies. We hypothesized that fetal ultrasonography and/or maternal blood markers are useful to identify LOS. Bovine fetuses were generated by artificial insemination (control) or IVP. Fetal ultrasonographies were taken on gestation D55 (D55) and fetal collections performed on D56 or D105 (gestation in cattle ≈ D280). IVP fetuses weighing ≥ 97 percentile of the control weight were considered LOS. Ultrasonography results show that the product of six D55 measurements can be used to identify extreme cases of LOS. To determine whether maternal blood can be used to identify LOS, leukocyte mRNA from 23 females was sequenced. Unsupervised hierarchical clustering grouped the transcriptomes of the two females carrying the two largest LOS fetuses. Comparison of the leukocyte transcriptomes of these two females to the transcriptome of all other females identified several misregulated transcripts on gestation D55 and D105 with LOC783838 and PCDH1 being misregulated at both time-points. Together our data suggest that LOS is identifiable during pregnancy in cattle.
Background Assisted Reproductive Technologies (ART) use can increase the risk of congenital overgrowth syndromes, such as large offspring syndrome (LOS) in ruminants. Epigenetic variations are known to influence gene expression and differentially methylated regions (DMRs) were previously determined to be associated with LOS in cattle. We observed DMRs overlapping tRNA clusters which could affect tRNA abundance and be associated with tissue specificity or overgrowth. Variations in tRNA expression have been identified in several disease pathways suggesting an important role in the regulation of biological processes. Understanding the role of tRNA expression in cattle offers an opportunity to reveal mechanisms of regulation at the translational level. We analyzed tRNA expression in the skeletal muscle and liver tissues of day 105 artificial insemination-conceived, ART-conceived with a normal body weight, and ART-conceived bovine fetuses with a body weight above the 97 th percentile compared to Control-AI. Results Despite the centrality of tRNAs to translation, in silico predictions have revealed dramatic differences in the number of tRNA genes between humans and cattle (597 vs 1,659). Consistent with reports in human, only a fraction of predicted tRNA genes are expressed. We detected the expression of 474 and 487 bovine tRNA genes in the muscle and liver with the remainder being unexpressed. 193 and 198 unique tRNA sequences were expressed in all treatment groups within muscle and liver respectively. In addition, an average of 193 tRNA sequences were expressed within the same treatment group in different tissues. Some tRNA isodecoders were differentially expressed between treatment groups. In the skeletal muscle and liver, we categorized 11 tRNA isoacceptors with undetected expression as well as an isodecoder that was unexpressed in the liver (Ser GGA ). Our results identified variation in the proportion of tRNA gene copies expressed between tissues and differences in the highest contributing tRNA anticodon within an amino acid family due to treatment and tissue type. Out of all amino acid families, roughly half of the most highly expressed tRNA isoacceptors correlated to their most frequent codon in the bovine genome. Conclusion Although the number of bovine tRNA genes is nearly triple of that of the tRNA genes in human, there is a shared occurrence of transcriptionally inactive tRNA genes in both species. We detected differential expression of tRNA genes as well as tissue- and treatment- specific tRNA transcripts with unique sequence variations that could modulate translation during protein homeostasis or cellular stress, and give rise to regulatory products targeting genes related to overgrowth in the skeletal muscle and/or tumor development in the liver of LOS individuals. While the absence of certain isodecoders may be relieved by wobble base pairing, missing tRNA species could increase the likelihood of mistranslation or mRNA degradation.
The DNA damage is a major problem that leads to mutagenesis and premature aging. Intriguingly, DNA damage repair (DDR) machinery is not robust in mammalian oocytes. The underlying mechanisms of this weakened DDR are unknown. Using the mouse oocyte as a model system, we found that DDR is dysfunctional in oocytes, leading to the development of aneuploid oocytes. Our data reveal that oocyte failure to repair damaged DNA is due to the inability of DDR protein, RAD51, to access altered "closed" chromatin conformation in DNA-damaged oocytes. Our data also demonstrate that, unlike somatic cells, oocytes fail to activate autophagy in response to DNA damage, which is the cause of altered chromatin conformation and inefficient DDR. Importantly, autophagy induction rescued DDR function and decreased aneuploidy in both DNA-damaged oocytes and oocytes from maternally aged mice which are prone to severe DNA damage. Our findings provide evidence that reduced autophagy contributes to weakened DDR in oocytes, especially in those from aged females, and offer scope to improve assisted reproductive therapy in women with compromised oocyte quality.Funding Information: This research was supported by laboratory start-up funding from the University of Missouri and a research grant from the American Society for Reproductive Medicine to A.Z.B. P.S was funded by USDA National Institute of Food and Agriculture, Agriculture and Food Research Initiative Competitive Grants no. grant number 2020-67015-31017 and seed funding from the College of Agriculture, Food and Natural Resources, University of Missouri (P.S.)Declaration of Interests: The authors declare no competing interests.Ethics Approval Statement: Mice were kept and experiments were performed in accordance with the Animal Care and Use guidelines of the University of Missouri (Animal Care Quality Assurance). This study was approved by the Animal Care Quality Assurance committee at the University of Missouri (Animal Care Quality Assurance Ref. Number, 17180)
Large offspring syndrome (LOS) and Beckwith-Wiedemann syndrome are similar epigenetic congenital overgrowth conditions in ruminants and humans, respectively. We have reported global loss-of-imprinting, methylome epimutations, and gene misregulation in LOS. However, less than 4% of gene misregulation can be explained with short range (<20kb) alterations in DNA methylation. Therefore, we hypothesized that methylome epimutations in LOS affect chromosome architecture which results in misregulation of genes located at distances >20kb in cis and in trans (other chromosomes). Our analyses focused on two imprinted domains that frequently reveal misregulation in these syndromes, namely KvDMR1 and IGF2R. Using bovine fetal fibroblasts, we identified CTCF binding at IGF2R imprinting control region but not KvDMR1, and allele-specific chromosome architecture of these domains in controls. In LOS, analyses identified erroneous long-range contacts and clustering tendency in the direction of expression of misregulated genes. In conclusion, altered chromosome architecture is associated with LOS.
Large/abnormal offspring syndrome (LOS/AOS) is a congenital overgrowth syndrome reported in ruminants produced by assisted reproduction (ART-LOS) which exhibit global disruption of the epigenome and transcriptome. LOS/AOS shares phenotypes and epigenotypes with the human congenital overgrowth condition Beckwith-Wiedemann syndrome. We have reported that LOS occurs spontaneously (SLOS); however, to date, no study has been conducted to determine if SLOS has the same methylome epimutations as ART-LOS. In this study, we performed whole-genome bisulphite sequencing to examine global DNA methylation in bovine SLOS and ART-LOS tissues. We observed unique patterns of global distribution of differentially methylated regions (DMRs) over different genomic contexts, such as promoters, CpG Islands, shores and shelves, as well as at repetitive sequences. In addition, we included data from two previous LOS studies to identify shared vulnerable genomic loci in LOS. Overall, we identified 320 genomic loci in LOS that have alterations in DNA methylation when compared to controls. Specifically, there are 25 highly vulnerable loci that could potentially serve as molecular markers for the diagnosis of LOS, including at the promoters of DMRT2 and TBX18, at the imprinted gene bodies of IGF2R, PRDM8, and BLCAP/NNAT, and at multiple CpG Islands. We also observed tissue-specific DNA methylation patterns between muscle and blood, and conservation of ART-induced DNA methylation changes between muscle and blood. We conclude that as ART-LOS, SLOS is an epigenetic condition. In addition, SLOS and ART-LOS share similarities in methylome epimutations.
Serum supplementation during bovine embryo culture has been demonstrated to promote cell proliferation and preimplantation embryo development. However, these desirable outcomes, have been associated with gene expression alterations of pathways involved in macroautophagy, growth, and development at the blastocyst stage, as well as with developmental anomalies such as fetal overgrowth and placental malformations. In order to start dissecting the molecular pathways by which serum supplementation of the culture medium during the preimplantation stage promotes developmental abnormalities, we examined blastocyst morphometry, inner cell mass and trophectoderm cell allocations, macroautophagy, and endoplasmic reticulum stress. On day 5 post-insemination, > 16 cells embryos were selected and cultured in medium containing 10% serum or left as controls. Embryo diameter, inner cell mass and trophectoderm cell number, and macroautophagy were measured on day 8 blastocysts (BL) and expanded blastocysts (XBL). On day 5 and day 8, we assessed transcript level of the ER stress markers HSPA5, ATF4, MTHFD2, and SHMT2 as well as XBP1 splicing (a marker of the unfolded protein response). Serum increased diameter and proliferation of embryos when compared to the no-serum group. In addition, serum increased macroautophagy of BL when compared to controls, while the opposite was true for XBL. None of the genes analyzed was differentially expressed at any stage, except that serum decreased HSPA5 in day 5 > 16 cells stage embryos. XBP1 splicing was decreased in BL when compared to XBL, but only in the serum group. Our data suggest that serum rescues delayed embryos by alleviating endoplasmic reticulum stress and promotes development of advanced embryos by decreasing macroautophagy.
In cattle, the use of assisted reproductive technologies (ART) can result in a congenital overgrowth condition known as large/abnormal offspring syndrome (LOS/AOS). The phenotypic characteristics of LOS include; somatic overgrowth, abdominal wall defects, large organs, breathing difficulties, skeletal defects, hypoglycemia, abnormal placentas, difficulty suckling, and perinatal death. LOS can have detrimental effects on the offspring and dam and also pose managerial and financial challenges to the producer. Research from the Rivera laboratory has demonstrated that LOS is an epigenetic syndrome. As in cattle, ART can promote the development of congenital overgrowth in humans, a condition known as Beckwith Wiedemann Syndrome (BWS). For the past 13 years, the Rivera laboratory has been characterizing LOS and we have shown that LOS and BWS are phenotypically and epigenotypically similar. In our studies, using gestation day ~105 Bos taurus taurus x Bos taurus indicus F1 hybrids, we showed global misregulation of imprinted and non-imprinted transcripts, micro RNAs and global misregulation of DNA methylation. In brief, LOS fetuses displayed variable loss-of-imprinting in kidney, liver, muscle and brain, when compared to controls. Biallelic expression of imprinted genes in LOS was associated with tissue-specific hypomethylation of the normally methylated parental allele. Not only was there loss of allele-specific expression of imprinted genes in LOS, but we also observed differential transcript amounts of these genes between control and overgrown fetuses. In addition, a positive correlation was observed between bodyweight and the number of biallelically expressed imprinted genes in LOS fetuses. From this work, we concluded that LOS is a multi-locus loss-of-imprinting condition. Current work, aims to determine if LOS is identifiable during pregnancy using day 55 fetal ultrasonography and day 55 and 105 maternal blood. In addition, we aim to determine how serum supplementation of culture medium can program preimplantation embryos to develop LOS. Findings will be discussed.
Early life adversity is widely recognized as a key risk factor for early developmental perturbations and contributes to the presentation of neuropsychiatric disorders in adulthood. Neurodevelopmental disorders exhibit a strong sex-bias in susceptibility, presentation, onset and severity, although the underlying mechanisms conferring vulnerability are not well understood. Environmental perturbations during pregnancy, such as malnutrition or stress, have been associated with sex-specific reprogramming that contribute to increased disease risk in adulthood, whereby stress and nutritional insufficiency may be additive and further exacerbate poor offspring outcomes. To determine whether maternal supplementation of docosahexanoic acid (DHA) exerts an effect on offspring outcome following exposure to early prenatal stress (EPS), dams were fed a purified 10:1 omega-6/omega-3 diet supplemented with either 1.0% preformed DHA/kg feed weight (DHA-enriched) or no additional DHA (denoted as the control diet, CTL). Dams were administered chronic variable stress during the first week of pregnancy (Embryonic day, E0.5 – 7.5) and developmental milestones were assessed at E 12.5. Exposure to early prenatal stress (EPS) decreased placenta and embryo weight in males, but not females, exposed to the CTL diet. DHA-enrichment reversed the sex-specific decrease in placenta and embryo weight following EPS. Early prenatal exposure upregulated expression of genes associated with oxygen and nutrient transport, including hypoxia inducible factor 3α (HIF3α), peroxisome proliferator-activated receptor alpha (PPARα), and insulin like growth binding factor 1 (IGFBP1), in placenta of CTL diet males exposed to EPS. DHA-enrichment in EPS-exposed animals abrogated the male-specific upregulation of PPARα, HIF3α, and IGFBP1. Taken together, these studies suggest that maternal dietary DHA enrichment may buffer against maternal stress programming of sex-specific outcomes during early development.