Maternal propionate supplementation ameliorates glucose and lipid metabolic disturbance in hypoxia-induced fetal growth restriction

Nrf2 deficiency exacerbated pulmonary pyroptosis in maternal hypoxia-induced intrauterine growth restriction offspring mice

Maternal prenatal hypoxia is an important contributor to intrauterine growth restriction (IUGR), which impedes fetal lung maturation and leads to the development of chronic lung diseases. Although evidence suggests the involvement of pyroptosis in IUGR, the molecular mechanism of pyroptosis is still unclear. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been found to potentially interact with gasdermin D (GSDMD), the key protein responsible for pyroptosis, indicating its crucial role in inhibiting pyroptosis. Therefore, we hypothesized that Nrf2 deficiency is a key molecular responsible for lung pyroptosis in maternal hypoxia-induced IUGR offspring mice. Pregnant WT and Nrf2-/- mice were exposed to hypoxia (10.5 % O2) to mimic IUGR model. We assessed body weight, lung histopathology, pulmonary angiogenesis, oxidative stress levels, as well as mRNA and protein expressions related to inflammation in the 2-week-old offspring. Additionally, we conducted a dual-luciferase reporter assay to confirm the targeting relationship between Nrf2 and GSDMD. Our findings revealed that offspring with maternal hypoxia-induced IUGR exhibited reduced birth weight, catch-up growth delay, and pulmonary dysplasia. Furthermore, we observed impaired nuclear translocation of Nrf2 and increased GSDMD-mediated pyroptosis in these offspring with IUGR. Moreover, the dual-luciferase reporter assay demonstrated that Nrf2 could directly inhibit GSDMD transcription; deficiency of Nrf2 exacerbated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR. Collectively, our findings suggest that Nrf2 deficiency induces GSDMD-mediated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR; thus highlighting the potential therapeutic approach of targeting Nrf2 for treating prenatal hypoxia-induced pulmonary dysplasia in offspring.

Maternal Dietary Strategies for Improving Offspring Cardiovascular-Kidney-Metabolic Health: A Scoping Review

Dietary regulation has been recognized for its profound impact on human health. The convergence of cardiovascular, kidney, and metabolic disorders at the pathophysiological level has given rise to cardiovascular-kidney-metabolic (CKM) syndrome, which constitutes a significant global health burden. Maternal dietary nutrients play a crucial role in fetal development, influencing various programmed processes. This review emphasizes the effects of different types of dietary interventions on each component of CKM syndrome in both preclinical and clinical settings. We also provide an overview of potential maternal dietary strategies, including amino acid supplementation, lipid-associated diets, micronutrients, gut microbiota-targeted diets, and plant polyphenols, aimed at preventing CKM syndrome in offspring. Additionally, we discuss the mechanisms mediated by nutrient-sensing signals that contribute to CKM programming. Altogether, we underscore the interaction between maternal dietary interventions and the risk of CKM syndrome in offspring, emphasizing the need for continued research to facilitate their clinical translation.

Supplementation with dimethylglycine sodium salt improves lipid metabolism disorder in intrauterine growth-retarded pigs

This study aims to elucidate the mechanism of lipid metabolism disorder in intrauterine growth retardation (IUGR) pigs and the potential alleviating effects of dimethylglycine sodium salt (DMG-Na). A total of 60 male newborn piglets were selected for this study. Within each litter, one normal birth weight (NBW) male piglet (1.53 ± 0.04 kg) and two IUGR male piglets (0.76 ± 0.06 kg) were chosen based on their birth weight. The piglets were divided into three groups for the study: NBW pigs received a PBS gavage and a common basal diet (NBW-C group), IUGR pigs received the same PBS gavage and common basal diet (IUGR-C group), and IUGR pigs received a 70-mg DMG-Na gavage along with a common basal diet supplemented with 0.1% DMG-Na (IUGR-D group). At 150 d of age, all piglets underwent euthanasia by exsanguination following electrical stunning, after which plasma, liver, and longissimus dorsi (LM) samples were promptly collected. The IUGR-D group demonstrated improvements in plasma parameters (P < 0.05), with lower triglyceride and free fatty acid (FFA) values, and hormone levels (P < 0.05), with lower growth hormone, insulin, and homeostasis model assessment of insulin resistance values. Restoration of lipid metabolism was observed (P < 0.05), with lower triglyceride and FFA, and higher hepatic lipase and total lipase values in the liver, and lower triglyceride and FFA values in the LM. Mitochondrial ETC complexes showed increased levels (P < 0.05), including higher complex III values in the liver, and higher complex I, complex III, and complex V values in the LM. Enhanced levels of energy metabolites were noted (P < 0.05), with higher NAD+, NAD+/NADH, adenosine triphosphate, and mtDNA values, and lower NADH values in the liver and LM. Additionally, meat quality parameters showed improvement (P < 0.05), with higher pH 24 h and a∗ values, and lower drip loss 48 h, L∗, and b∗ values. The expressions of lipid metabolism and mitochondrial function-related genes and proteins were upregulated (P < 0.05) compared to the IUGR-C group. In conclusion, it was indicated that IUGR pigs experienced lipid metabolism disorders and diminished performance. However, supplementation with DMG-Na showed promise in mitigating these adverse physiological effects by safeguarding body tissues and modulating energy metabolism.

Developmental Programming of the Fetal Immune System by Maternal Western-Style Diet: Mechanisms and Implications for Disease Pathways in the Offspring

Maternal obesity and over/undernutrition can have a long-lasting impact on offspring health during critical periods in the first 1000 days of life. Children born to mothers with obesity have reduced immune responses to stimuli which increase susceptibility to infections. Recently, maternal western-style diets (WSDs), high in fat and simple sugars, have been associated with skewing neonatal immune cell development, and recent evidence suggests that dysregulation of innate immunity in early life has long-term consequences on metabolic diseases and behavioral disorders in later life. Several factors contribute to abnormal innate immune tolerance or trained immunity, including changes in gut microbiota, metabolites, and epigenetic modifications. Critical knowledge gaps remain regarding the mechanisms whereby these factors impact fetal and postnatal immune cell development, especially in precursor stem cells in bone marrow and fetal liver. Components of the maternal microbiota that are transferred from mothers consuming a WSD to their offspring are understudied and identifying cause and effect on neonatal innate and adaptive immune development needs to be refined. Tools including single-cell RNA-sequencing, epigenetic analysis, and spatial location of specific immune cells in liver and bone marrow are critical for understanding immune system programming. Considering the vital role immune function plays in offspring health, it will be important to understand how maternal diets can control developmental programming of innate and adaptive immunity.

MCT1-mediated transport of valeric acid promotes porcine preimplantation embryo development by improving mitochondrial function and inhibiting the autophagic AMPK-ULK1 pathway

Oocytes and embryos are highly sensitive to environmental stress in vivo and in vitro. During in vitro culture, many stressful conditions can affect embryo quality and viability, leading to adverse clinical outcomes such as abortion and congenital abnormalities. In this study, we found that valeric acid (VA) increased the mitochondrial membrane potential and ATP content, decreased the level of reactive oxygen species that the mitochondria generate, and thus improved mitochondrial function during early embryonic development in pigs. VA decreased expression of the autophagy-related factors LC3B and BECLIN1. Interestingly, VA inhibited expression of autophagy-associated phosphorylation-adenosine monophosphate-activated protein kinase (p-AMPK), phosphorylation-UNC-51-like autophagy-activated kinase 1 (p-ULK1, Ser555), and ATG13, which reduced apoptosis. Short-chain fatty acids (SCFAs) can signal through G-protein-coupled receptors on the cell membrane or enter the cell directly through transporters. We further show that the monocarboxylate transporter 1 (MCT1) was necessary for the effects of VA on embryo quality, which provides a new molecular perspective of the pathway by which SCFAs affect embryos. Importantly, VA significantly inhibited the AMPK-ULK1 autophagic signaling pathway through MCT1, decreased apoptosis, increased expression of embryonic pluripotency genes, and improved embryo quality.

Single-cell RNA sequencing reveals association of aberrant placental trophoblasts and FN1 reduction in late-onset fetal growth restriction

INTRODUCTION

Fetal growth restriction (FGR) can lead to fetal mental development abnormalities, malformations, and even intrauterine death. Defects in the trophoblasts at the maternal-fetal interface may contribute to FGR. However, the impact of trophoblasts on FGR is still not well understood. Therefore, the objective of this study is to characterize the heterogeneity of placental cells at the single-cell level and investigate the role of trophoblast subtypes in the pathogenesis of FGR at the cellular and molecular levels.

METHODS

Single-cell RNA sequencing was performed on the maternal side of placentas from two normal pregnant women and two pregnant women with FGR. Lentivirus transfection was used to establish a FN1 knockout model in trophoblast HTR-8-Svneo cells. The effect of FN1 knockout on cell migration and invasion of HTR-8-Svneo cells was assessed through wound healing and transwell assays.

RESULTS

Nine cell types were annotated in 39,161 cells derived from single-cell RNA sequencing. The FGR group exhibited a decrease in the percentage of trophoblasts, especially in subtype of extravillous trophoblasts (EVTs). The expression of FN1 was reduced in trophoblasts and EVTs. Furthermore, the protein expression levels of FN1 in the placentas of FGR patients were significantly lower than those of normal pregnant women. The cell migration and invasion ability of HTR-8-Svneo cells were inhibited after the knockdown of FN1.

DISCUSSION

The dysregulation of the trophoblast subtype-EVTs is involved in placental dysplasia related to FGR. The association between aberrant placental trophoblasts and reduced FN1 expression may contribute to insufficient remodeling of spiral arteries and the formation of FGR.

β-hydroxybutyrate administration improves liver injury and metabolic abnormality in postnatal growth retardation piglets

Abnormal hepatic energy metabolism limits the growth and development of piglets. We hypothesized that β-hydroxybutyrate (BHB) might improve the growth performance of piglets by maintaining hepatic caloric homeostasis. A total of 30 litters of newborn piglets were tracked, and 30 postnatal growth retardation (PGR) piglets and 40 healthy piglets were selected to treat with normal saline with or without BHB (25 mg/kg/days) at 7-d-old. At the age of 42 days, 8 piglets in each group were sacrificed, and serum and liver were collected. Compared with the healthy-control group piglets, PGR piglets showed lower body weight (BW) and liver weight (p < 0.05), and exhibited liver injury and higher inflammatory response. The contents of serum and hepatic BHB were lower (p < 0.05), and gene expression related to hepatic ketone body production were down-regulated in PGR piglets (p < 0.05). While BHB treatment increased BW and serum BHB levels, but decreased hepatic BHB levels in PGR piglets (p < 0.05). BHB alleviated the liver injury by inhibiting the apoptosis and inflammation in liver of PGR piglets (p < 0.05). Compared with the healthy-control group piglets, liver glycogen content and serum triglyceride level of PGR piglets were increased (p < 0.05), liver gluconeogenesis gene and lipogenesis gene expression were increased (p < 0.05), and liver NAD+ level was decreased (p < 0.05). BHB supplementation increased the ATP levels in serum and liver (p < 0.05), whereas decreased the serum glucose, cholesterol, triglyceride and high-density lipoprotein cholesterol levels and glucose and lipid metabolism in liver of PGR piglets (p < 0.05). Therefore, BHB treatment might alleviate the liver injury and inflammation, and improve hepatic energy metabolism by regulating glucose and lipid metabolism, thereby improving the growth performance of PGR piglets.

Early Colonization of the Intestinal Microbiome of Neonatal Piglets Is Influenced by the Maternal Microbiome

The intestinal microbiome plays a crucial role in animal health and growth by interacting with the host, inhibiting pathogenic microbial colonization, and regulating immunity. This study investigated dynamic changes in the fecal microbial composition of piglets from birth through weaning and the relationship between the piglet fecal microbiome and sows. Feces, skin, neonatal oral cavity, and vaginal samples were collected from eight sows and sixty-three piglets, and 16S genome sequencing was performed. The results revealed that Firmicutes, Bacteroidetes, and Proteobacteria dominated the piglet microbiome in the early stages, and Firmicutes and Bacteroidetes were crucial for maintaining a balance in the intestinal microbiome during nursing. The abundance of Christensenellaceae_R-7_group, Succinivibrio, and Prevotella increased in weaned piglets fed solid feed. Analysis of the microbiome from sows to piglets indicated a shift in the microbiome colonizing piglet intestines, which became a significant constituent of the piglet intestinal microbiome. This study supports the theory that the neonatal intestinal microbiome is vertically transmitted from the mother. Further research is required to integrate factors related to sows, piglets, and their environments to gain a better understanding of the early establishment of the intestinal microbiome in piglets.

Integrative profiling of extrachromosomal circular DNA in placenta and maternal plasma provides insights into the biology of fetal growth restriction and reveals potential biomarkers

Introduction: Fetal growth restriction (FGR) is a placenta-mediated pregnancy complication that predisposes fetuses to perinatal complications. Maternal plasma cell-free DNA harbors DNA originating from placental trophoblasts, which is promising for the prenatal diagnosis and prediction of pregnancy complications. Extrachromosomal circular DNA (eccDNA) is emerging as an ideal biomarker and target for several diseases. Methods: We utilized eccDNA sequencing and bioinformatic pipeline to investigate the characteristics and associations of eccDNA in placenta and maternal plasma, the role of placental eccDNA in the pathogenesis of FGR, and potential plasma eccDNA biomarkers of FGR. Results: Using our bioinformatics pipelines, we identified multi-chromosomal-fragment and single-fragment eccDNA in placenta, but almost exclusively single-fragment eccDNA in maternal plasma. Relative to that in plasma, eccDNA in placenta was larger and substantially more abundant in exons, untranslated regions, promoters, repetitive elements [short interspersed nuclear elements (SINEs)/Alu, SINEs/mammalian-wide interspersed repeats, long terminal repeats/endogenous retrovirus-like elements, and single recognition particle RNA], and transcription factor binding motifs. Placental multi-chromosomal-fragment eccDNA was enriched in confident enhancer regions predicted to pertain to genes in apoptosis, energy, cell growth, and autophagy pathways. Placental eccDNA-associated genes whose abundance differed between the FGR and control groups were associated with immunity-related gene ontology (GO) terms. The combined analysis of plasma and placental eccDNA-associated genes in the FGR and control groups led to the identification of potential biomarkers that were assigned to the GO terms of the epigenetic regulation of gene expression and nutrient-related processes, respectively. Conclusion: Together, our results highlight links between placenta functions and multi-chromosomal-fragment and single-fragment eccDNA. The integrative analysis of placental and plasma eccDNA confirmed the potential of these molecules as disease-specific biomarkers of FGR.

Alterations in the Gut Microbiome and Metabolisms in Pregnancies with Fetal Growth Restriction

Fetuses diagnosed with fetal growth restriction (FGR) are at an elevated risk of stillbirth and adulthood morbidity. Gut dysbiosis has emerged as one of the impacts of placental insufficiency, which is the main cause of FGR. This study aimed to characterize the relationships among the intestinal microbiome, metabolites, and FGR. Characterization was conducted on the gut microbiome, fecal metabolome, and human phenotypes in a cohort of 35 patients with FGR and 35 normal pregnancies (NP). The serum metabolome was analyzed in 19 patients with FGR and 31 normal pregnant women. Multidimensional data was integrated to reveal the links between data sets. A fecal microbiota transplantation mouse model was used to determine the effects of the intestinal microbiome on fetal growth and placental phenotypes. The diversity and composition of the gut microbiota were altered in patients with FGR. A group of microbial species altered in FGR closely correlated with fetal measurements and maternal clinical variables. Fecal and serum metabolism profiles were distinct in FGR patients compared to those in the NP group. Altered metabolites were identified and associated with clinical phenotypes. Integrated multi-omics analysis revealed the interactions among gut microbiota, metabolites, and clinical measurements. Microbiota from FGR gravida transplanted to mice progestationally induced FGR and placental dysfunction, including impaired spiral artery remodeling and insufficient trophoblast cell invasion. Taken together, the integration of microbiome and metabolite profiles from the human cohort indicates that patients with FGR endure gut dysbiosis and metabolic disorders, which contribute to disease pathogenesis. IMPORTANCE Downstream of the primary cause of fetal growth restriction are placental insufficiency and fetal malnutrition. Gut microbiota and metabolites appear to play an important role in the progression of gestation, while dysbiosis induces maternal and fetal complications. Our study elaborates the significant differences in microbiota profiles and metabolome characteristics between women with FGR and normal pregnancies. This is the first attempt so far that reveals the mechanistic links in multi-omics in FGR, providing a novel insight into host-microbe interaction in placenta-derived diseases.