High-fat diet intake modulates maternal intestinal adaptations to pregnancy and results in placental hypoxia, as well as altered fetal gut barrier proteins and immune markers

Intestinal alterations and mild glucose homeostasis impairments in the offspring born to overweight rats

The gut plays a crucial role in metabolism by regulating the passage of nutrients, water and microbial-derived substances to the portal circulation. Additionally, it produces incretins, such as glucose-insulinotropic releasing peptide (GIP) and glucagon-like derived peptide 1 (GLP1, encoded by gcg gene) in response to nutrient uptake. We aimed to investigate whether offspring from overweight rats develop anomalies in the barrier function and incretin transcription. We observed pro-inflammatory related changes along with a reduction in Claudin-3 levels resulting in increased gut-permeability in fetuses and offspring from overweight rats. Importantly, we found decreased gip mRNA levels in both fetuses and offspring from overweight rats. Differently, gcg mRNA levels were upregulated in fetuses, downregulated in female offspring and unchanged in male offspring from overweight rats. When cultured with high glucose, intestinal explants showed an increase in gip and gcg mRNA levels in control offspring. In contrast, offspring from overweight rats did not exhibit any response in gip mRNA levels. Additionally, while females showed no response, male offspring from overweight rats did exhibit an upregulation in gcg mRNA levels. Furthermore, female and male offspring from overweight rats showed sex-dependent anomalies when orally challenged with a glucose overload, returning to baseline glucose levels after 120 min. These results open new research questions about the role of the adverse maternal metabolic condition in the programming of impairments in glucose homeostasis, enteroendocrine function and gut barrier function in the offspring from overweight mothers and highlight the importance of a perinatal maternal healthy metabolism.

The influence of maternal diet on offspring's gut microbiota in early life

BACKGROUND

The influence of maternal diet on offspring's health is an area of study that is linked to epigenetics. Maternal diet contributes to determining the health status of offspring and maternally linked mechanisms and is a global health challenge that requires attention. The impact of gut microbiota on host metabolism and offspring health is still not established.

OBJECTIVE

In this review, we intend to discuss the evidence on the impact of maternal diet and the health of offspring gut microbiota. The paper focuses on the gut microbiome of animal models. It captures the maternal diet and its influence on the offspring's gut microbiota, behavior that is supported by cell experimental results. Both inflammation and immune status of offspring induced by maternal diet are discussed. Finally, this review used predicted biological pathways involved in maternal diet and offspring health, and the influence of maternal diet on gut microbiota and offspring behavior. Obesity, diabetes, asthma and allergies, and neurodegenerative disorders and prospects for maternal diet, and microbiota and offspring health were discussed.

CONCLUSION

The review was able to gather that a high-fat diet during pregnancy created a long-lasting metabolic signature on the infant's innate immune system, altering inflammation in the offspring microbiota, which predisposed offspring to obesity and metabolic diseases in adulthood.

Obesogenic Diet in Mice Leads to Inflammation and Oxidative Stress in the Mother in Association with Sex-Specific Changes in Fetal Development, Inflammatory Markers and Placental Transcriptome

BACKGROUND

Obesity during pregnancy is related to adverse maternal and neonatal outcomes. Factors involved in these outcomes may include increased maternal insulin resistance, inflammation, oxidative stress, and nutrient mishandling. The placenta is the primary determinant of fetal outcomes, and its function can be impacted by maternal obesity. The aim of this study on mice was to determine the effect of obesity on maternal lipid handling, inflammatory and redox state, and placental oxidative stress, inflammatory signaling, and gene expression relative to female and male fetal growth.

METHODS

Female mice were fed control or obesogenic high-fat/high-sugar diet (HFHS) from 9 weeks prior to, and during, pregnancy. On day 18.5 of pregnancy, maternal plasma, and liver, placenta, and fetal serum were collected to examine the immune and redox states. The placental labyrinth zone (Lz) was dissected for RNA-sequencing analysis of gene expression changes.

RESULTS

the HFHS diet induced, in the dams, hepatic steatosis, oxidative stress (reduced catalase, elevated protein oxidation) and the activation of pro-inflammatory pathways (p38-MAPK), along with imbalanced circulating cytokine concentrations (increased IL-6 and decreased IL-5 and IL-17A). HFHS fetuses were asymmetrically growth-restricted, showing sex-specific changes in circulating cytokines (GM-CSF, TNF-α, IL-6 and IFN-γ). The morphology of the placenta Lz was modified by an HFHS diet, in association with sex-specific alterations in the expression of genes and proteins implicated in oxidative stress, inflammation, and stress signaling. Placental gene expression changes were comparable to that seen in models of intrauterine inflammation and were related to a transcriptional network involving transcription factors, LYL1 and PLAG1.

CONCLUSION

This study shows that fetal growth restriction with maternal obesity is related to elevated oxidative stress, inflammatory pathways, and sex-specific placental changes. Our data are important, given the marked consequences and the rising rates of obesity worldwide.

Foodborne Carbon Dots Aggravate High-Fat-Diet-Induced Glucose Homeostasis Imbalance by Disrupting the Gut-Liver Axis

Foodborne carbon dots (CDs) are generally produced during cooking and exist in food items. Generally, CDs are regarded as nontoxic materials, but several studies have gradually confirmed the cytotoxicity of CDs, such as oxidative stress, reduced cellular activity, apoptosis, etc. However, studies focusing on the health effects of long-term intake of food-borne CDs are scarce, especially in populations susceptible to metabolic disease. In this study, we reported that CDs in self-brewing beer had no effect on glucose metabolism in CHOW-fed mice but exacerbated high-fat-diet (HFD)-induced glucose metabolism disorders via the gut-liver axis. Chronic exposure to foodborne CDs increased fasting glucose levels and exacerbated liver and intestinal barrier damage in HFD-fed mice. The 16s rRNA sequencing analysis revealed that CDs significantly altered the gut microbiota composition and promoted lipopolysaccharide (LPS) synthesis-related KEGG pathways (superpathway of (Kdo)2-lipid A, Kdo transfer to lipid IVA Ill (Chlamydia), lipid IVA biosynthesis, and so on) in HFD-fed mice. Mechanically, CD exposure increased the abundance of Gram-negative bacteria (Proteobacteria and Desulfovibrionaceae), thus producing excessive endotoxin-LPS, and then LPS was transferred by the blood circulation to the liver due to the damaged intestinal barrier. In the liver, LPS promoted TLR4/NF-κB/P38 MAPK signaling, thus enhancing systemic inflammation and exacerbating HFD-induced insulin resistance. However, pretreating mice with antibiotics eliminated these effects, indicating a key role for gut microbiota in CDs exacerbating glucose metabolism disorders in HFD-fed mice. The finding herein provides new insight into the potential health risk of foodborne nanoparticles in susceptible populations by disturbing the gut-liver axis.

Maternal Phlorizin Intake Protects Offspring from Maternal Obesity-Induced Metabolic Disorders in Mice via Targeting Gut Microbiota to Activate the SCFA-GPR43 Pathway

Maternal obesity increases the risk of obesity and metabolic disorders (MDs) in offspring, which can be mediated by the gut microbiota. Phlorizin (PHZ) can improve gut dysbiosis and positively affect host health; however, its transgenerational metabolic benefits remain largely unclear. This study aimed to investigate the potential of maternal PHZ intake in attenuating the adverse impacts of a maternal high-fat diet on obesity-related MDs in dams and offspring. The results showed that maternal PHZ reduced HFD-induced body weight gain and fat accumulation and improved glucose intolerance and abnormal lipid profiles in both dams and offspring. PHZ improved gut dysbiosis by promoting expansion of SCFA-producing bacteria, Akkermansia and Blautia, while inhibiting LPS-producing and pro-inflammatory bacteria, resulting in significantly increased fecal SCFAs, especially butyric acid, and reduced serum lipopolysaccharide levels and intestinal inflammation. PHZ also promoted intestinal GLP-1/2 secretion and intestinal development and enhanced gut barrier function by activating G protein-coupled receptor 43 (GPR43) in the offspring. Antibiotic-treated mice receiving FMT from PHZ-regulated offspring could attenuate MDs induced by receiving FMT from HFD offspring through the gut microbiota to activate the GPR43 pathway. It can be regarded as a promising functional food ingredient for preventing intergenerational transmission of MDs and breaking the obesity cycle.

Placental inflammation, oxidative stress, and fetal outcomes in maternal obesity

The obesity epidemic has led to a growing body of research investigating the consequences of maternal obesity on pregnancy and offspring health. The placenta, traditionally viewed as a passive intermediary between mother and fetus, is known to play a critical role in modulating the intrauterine environment and fetal development, and we now know that maternal obesity leads to increased inflammation, oxidative stress, and altered placental function. Here, we review recent research exploring the involvement of inflammation and oxidative stress as mechanisms impacting the placenta and fetus during obese pregnancy. Understanding them is crucial for informing strategies that can mitigate the adverse health effects of maternal obesity on offspring development and disease risk.

Melatonin alleviates high temperature exposure induced fetal growth restriction via the gut-placenta-fetus axis in pregnant mice

INTRODUCTION

Global warming augments the risk of adverse pregnancy outcomes in vulnerable expectant mothers. Pioneering investigations into heat stress (HS) have predominantly centered on its direct impact on reproductive functions, while the potential roles of gut microbiota, despite its significant influence on distant tissues, remain largely unexplored. Our understanding of deleterious mechanisms of HS and the development of effective intervention strategies to mitigate the detrimental impacts are still limited.

OBJECTIVES

In this study, we aimed to explore the mechanisms by which melatonin targets gut microbes to alleviate HS-induced reproductive impairment.

METHODS

We firstly evaluated the alleviating effects of melatonin supplementation on HS-induced reproductive disorder in pregnant mice. Microbial elimination and fecal microbiota transplantation (FMT) experiments were then conducted to confirm the efficacy of melatonin through regulating gut microbiota. Finally, a lipopolysaccharide (LPS)-challenged experiment was performed to verify the mechanism by which melatonin alleviates HS-induced reproductive impairment.

RESULTS

Melatonin supplementation reinstated gut microbiota in heat stressed pregnant mice, reducing LPS-producing bacteria (Aliivibrio) and increasing beneficial butyrate-producing microflora (Butyricimonas). This restoration corresponded to decreased LPS along the maternal gut-placenta-fetus axis, accompanied by enhanced intestinal and placental barrier integrity, safeguarding fetuses from oxidative stress and inflammation, and ultimately improving fetal weight. Further pseudo-sterile and fecal microbiota transplantation trials confirmed that the protective effect of melatonin on fetal intrauterine growth under HS was partially dependent on gut microbiota. In LPS-challenged pregnant mice, melatonin administration mitigated placental barrier injury and abnormal angiogenesis via the inactivation of the TLR4/MAPK/VEGF signaling pathway, ultimately leading to enhanced nutrient transportation in the placenta and thereby improving the fetal weight.

CONCLUSION

Melatonin alleviates HS-induced low fetal weight during pregnancy via the gut-placenta-fetus axis, the first time highlighting the gut microbiota as a novel intervention target to mitigate the detrimental impact of global temperature rise on vulnerable populations.

Gut microbiota contributes to bisphenol A-induced maternal intestinal and placental apoptosis, oxidative stress, and fetal growth restriction in pregnant ewe model by regulating gut-placental axis

BACKGROUND

Bisphenol A (BPA) is an environmental contaminant with endocrine-disrupting properties that induce fetal growth restriction (FGR). Previous studies on pregnant ewes revealed that BPA exposure causes placental apoptosis and oxidative stress (OS) and decreases placental efficiency, consequently leading to FGR. Nonetheless, the response of gut microbiota to BPA exposure and its role in aggravating BPA-mediated apoptosis, autophagy, mitochondrial dysfunction, endoplasmic reticulum stress (ERS), and OS of the maternal placenta and intestine are unclear in an ovine model of gestation.

RESULTS

Two pregnant ewe groups (n = 8/group) were given either a subcutaneous (sc) injection of corn oil (CON group) or BPA (5 mg/kg/day) dissolved in corn oil (BPA group) once daily, from day 40 to day 110 of gestation. The maternal colonic digesta and the ileum and placental tissue samples were collected to measure the biomarkers of autophagy, apoptosis, mitochondrial dysfunction, ERS, and OS. To investigate the link between gut microbiota and the BPA-induced FGR in pregnant ewes, gut microbiota transplantation (GMT) was conducted in two pregnant mice groups (n = 10/group) from day 0 to day 18 of gestation after removing their intestinal microbiota by antibiotics. The results indicated that BPA aggravates apoptosis, ERS and autophagy, mitochondrial function injury of the placenta and ileum, and gut microbiota dysbiosis in pregnant ewes. GMT indicated that BPA-induced ERS, autophagy, and apoptosis in the ileum and placenta are attributed to gut microbiota dysbiosis resulting from BPA exposure.

CONCLUSIONS

Our findings indicate the underlying role of gut microbiota dysbiosis and gut-placental axis behind the BPA-mediated maternal intestinal and placental apoptosis, OS, and FGR. The findings further provide novel insights into modulating the balance of gut microbiota through medication or probiotics, functioning via the gut-placental axis, to alleviate gut-derived placental impairment or FGR. Video Abstract.

Maternal diet during gestation affect prostatic tissue component in SHR/Izm offspring

BACKGROUND

Numerous studies have investigated the associations between maternal nutritional status and various diseases, with the underlying mechanism often attributed to epigenetic changes. However, limited research has been conducted on the relationship between maternal nutrition and benign prostatic hyperplasia (BPH). In this study, we aimed to explore the potential association between maternal nutrition and BPH using an animal experiment and evaluating the findings through fluorescent immunostaining and genetic analysis.

METHODS

Female spontaneously hypertensive rats (SHR/Izm) were randomly assigned to three groups at the start of pregnancy: a standard diet group (SD; 17% protein, 7% fat), a low-protein diet group (LPD; 6% protein, 7% fat), and a high-fat diet group (HFD; 22% protein, 35% fat). The diets were maintained throughout gestation. After giving birth, both the mothers and their pups were exclusively fed a standard diet. Male pups were euthanized at 48 weeks, and their prostates were removed. The composition of the ventral prostate (VP) was evaluated using fluorescent immunostaining with antibodies for cytokeratin, vimentin, and Ki-67. Microarray analysis, real-time RT-PCR, and DNA methylation analysis using pyrosequencing were performed. Statistical analysis was conducted using one-way ANOVA and Tukey's multiple comparison test, with a significance level set at p < 0.05.

RESULTS

Pups in the LPD group exhibited significant underweight from birth (1 day; SD vs. LPD vs. HFD: 4.46 vs. 4.08 vs. 4.35, p = 0.04) until weaning (21 days; SD vs. LPD vs. HFD: 30.8 vs. 27.4 vs. 29.2, p = 0.03). However, they exhibited catch-up growth, and there was no significant difference at 48 weeks (p = 0.84). The epithelial area in the ventral prostate was significantly increased in the LPD group (SD vs. LPD vs. HFD: 39% vs. 48% vs. 37%, p = 0.01), while the stromal area was significantly increased in the HFD group (SD vs. LPD vs. HFD: 11% vs. 11% vs. 15%, p < 0.01). Gene ontology analysis of the gene expression microarray showed increased activity in developmental processes (SD vs. LPD: p = 6.3E-03, SD vs. HFD: p = 7.2E-03), anatomical structure development (SD vs. LPD: p = 6.3E-03, SD vs. HFD: p = 5.3E-03), and cell differentiation (SD vs. LPD: p = 0.018, SD vs. HFD: p = 0.041) in both the LPD and HFD groups. Real-time RT-PCR revealed high expression levels of the transcription factors NFκB (p < 0.01) and Smad3 (p < 0.01) in both the LPD and HFD groups. XIAP, an apoptosis inhibitor, was increased in the LPD group (p = 0.02). The TGF beta pathway, associated with epithelial mesenchymal transition (EMT), and vimentin (p < 0.01) were upregulated in the HFD group. Pyrosequencing DNA methylation analysis of the TGF beta pathway indicated hypomethylation of TGFb1, TGFbR1, and Smad3 in all groups, although there were no significant differences.

CONCLUSIONS

Our findings suggest that both maternal undernutrition and obesity influence the prostatic development of offspring. Maternal consumption of a low protein diet promotes epithelial hyperplasia through the upregulation of apoptosis inhibitors, while a high fat diet leads to increased stromal growth through the induction of EMT.

Bovine milk osteopontin improved intestinal health of pregnant rats fed a high-fat diet through improving bile acid metabolism

The main purpose of the current study was to investigate the ameliorative effects of bovine milk osteopontin (bmOPN) on the gut dysfunction of pregnant rats fed a high-fat diet (HFD). Bovine milk osteopontin was supplemented at a dose of 6 mg/kg body weight. Bovine milk osteopontin supplementation during pregnancy reduced colonic inflammation of HFD dams, and it also increased the colonic expression of ZO-1 and claudin-4 of HFD dams. Bovine milk osteopontin significantly enriched the relative abundance of Bacteroidetes, whereas it decreased Proteobacteria, Helicobacteraceae, and Desulfovibrionaceae in feces of HFD dams. The levels of isobutyric acid and pentanoic acid in the HFD + bmOPN group were higher than that of the HFD group. Functional predication analysis of microbial genomes revealed that bmOPN supplementation to HFD pregnancies changed 4 Kyoto Encyclopedia of Genes and Genomes pathways including bile acid biosynthesis. Further, bmOPN enriched hepatic taurochenodeoxycholic acid and tauroursodeoxycholic acid plus taurohyodeoxycholic acid in the gut of HFD maternal rats. Our findings suggested that bmOPN improved the gut health of HFD pregnant rats partially through modulating bile acid biosynthesis.

Impact of Maternal Mediterranean-Type Diet Adherence on Microbiota Composition and Epigenetic Programming of Offspring

Understanding how maternal diet affects in utero neonatal gut microbiota and epigenetic regulation may provide insight into disease origins and long-term health. The impact of Mediterranean diet pattern adherence (MDA) on fetal gut microbiome and epigenetic regulation was assessed in 33 pregnant women. Participants completed a validated food frequency questionnaire in each trimester of pregnancy; the alternate Mediterranean diet (aMED) score was applied. Umbilical cord blood, placental tissue, and neonatal meconium were collected from offspring. DNA methylation patterns were probed using the Illumnia EPICarray Methylation Chip in parturients with high versus low MDA. Meconium microbial abundance in the first 24 h after birth was identified using 16s rRNA sequencing and compared among neonates born to mothers with high and low aMED scores. Twenty-one mothers were classified as low MDA and 12 as high MDA. Pasteurellaceae and Bacteroidaceae trended towards greater abundance in the high-MDA group, as well as other short-chain fatty acid-producing species. Several differentially methylated regions varied between groups and overlapped gene regions including NCK2, SNED1, MTERF4, TNXB, HLA-DPB, BAG6, and LMO3. We identified a beneficial effect of adherence to a Mediterranean diet on fetal in utero development. This highlights the importance of dietary counseling for mothers and can be used as a guide for future studies of meconium and immuno-epigenetic modulation.

Heat Stress-Induced Fetal Intrauterine Growth Restriction Is Associated with Elevated LPS Levels Along the Maternal Intestine-Placenta-Fetus Axis in Pregnant Mice

The exacerbation of the greenhouse effect has made heat stress (HS) an important risk factor for the occurrence of intrauterine growth restriction (IUGR). The experiment aims to uncover the effects of maternal HS on IUGR and its mechanisms. The results showed that HS leads to decreased maternal and fetal birth weights, accompanied by increased serum oxidative stress and cortisol levels. Moreover, HS inflicted significant damage to both the intestinal and placental barriers, altering maternal gut microbiota and increasing intestinal LPS levels. As a result, LPS levels increased in maternal serum, placenta, and fetus. Furthermore, HS damaged the intestinal structure, intensifying inflammation and disrupting the redox balance. The placenta exposed to HS exhibited changes in the placental structure along with disrupted angiogenesis and decreased levels of nutritional transporters. Additionally, the leakage of LPS triggered placental JNK and ERK phosphorylation, ultimately inducing severe placental inflammation and oxidative stress. This study suggests that LPS translocation from the maternal intestine to the fetus, due to a disrupted gut microbiota balance and compromised intestinal and placental barrier integrity, may be the primary cause of HS-induced IUGR. Furthermore, increased LPS leakage leads to placental inflammation, redox imbalance, and impaired nutrient transport, further restricting fetal growth.

Polar lipid-enriched milk fat globule membrane supplementation in maternal high-fat diet promotes intestinal barrier function and modulates gut microbiota in male offspring

Intestinal development plays a critical role in physiology and disease in early life and has long-term effects on the health status throughout the lifespan. Maternal high-fat diet (HFD) fuels the inflammatory reaction and metabolic syndrome, disrupts intestinal barrier function, and alters gut microbiota in offspring. The aim of this study was to evaluate whether polar lipid-enriched milk fat globule membrane (MFGM-PL) supplementation in maternal HFD could promote intestinal barrier function and modulate gut microbiota in male offspring. Obese female rats induced by HFD were supplemented with MFGM-PL during pregnancy and lactation. The offspring were fed HFD for 11 weeks after weaning. MFGM-PL supplementation to dams fed HFD decreased the body weight gain and ameliorated abnormalities of serum insulin, lipids, and inflammatory cytokines in offspring at weaning. Maternal MFGM-PL supplementation promoted the intestinal barrier by increasing the expression of Ki-67, lysozyme, mucin 2, zonula occludens-1, claudin-3, and occludin. Additionally, MFGM-PL supplementation to HFD dams improved gut dysbiosis in offspring. MFGM-PL increased the relative abundance of Akkermansiaceae, Ruminococcaceae, and Blautia. Concomitantly, maternal MFGM-PL treatment increased short-chain fatty acids of colonic contents and G-protein-coupled receptor (GPR) 41 and GPR 43 expressions in the colon of offspring. Importantly, the beneficial effects of maternal MFGM-PL intervention persisted to offspring's adulthood, as evidenced by increased relative abundance of norank_f_Muribaculaceae, Peptostreptococcaceae and Romboutsia and modulated the taxonomic diversity of gut microbiota in adult offspring. In summary, maternal MFGM-PL supplementation improved intestinal development in the offspring of dams fed with HFD, which exerted long-term beneficial effects on offspring intestinal health.

Intestinal microbial circadian rhythms drive sex differences in host immunity and metabolism

Circadian rhythms dynamically regulate sex differences in metabolism and immunity, and circadian disruption increases the risk of metabolic disorders. We investigated the role of sex-specific intestinal microbial circadian rhythms in host metabolism using germ-free and conventionalized mice and manipulation of dietary-derived fat, fiber, and microbiota-accessible carbohydrates. Our findings demonstrate that sex differences in circadian rhythms of genes involved in immunity and metabolism depend on oscillations in microbiota, microbial metabolic functions, and microbial metabolites. Further, we show that consuming an obesogenic, high-fat, low-fiber diet produced sex-specific changes in circadian rhythms in microbiota, metabolites, and host gene expression, which were linked to sex differences in the severity of metabolic dysfunction. Our results reveal that microbial circadian rhythms contribute to sex differences in immunity and metabolism and that dietary factors can entrain new circadian rhythms and modify the magnitude of sex differences in host-microbe circadian dynamics.

Intestinal permeability and peripheral immune cell composition are altered by pregnancy and adiposity at mid- and late-gestation in the mouse

It is clear that the gastrointestinal tract influences metabolism and immune function. Most studies to date have used male test subjects, with a focus on effects of obesity and dietary challenges. Despite significant physiological maternal adaptations that occur across gestation, relatively few studies have examined pregnancy-related gut function. Moreover, it remains unknown how pregnancy and diet can interact to alter intestinal barrier function. In this study, we investigated the impacts of pregnancy and adiposity on maternal intestinal epithelium morphology, in vivo intestinal permeability, and peripheral blood immunophenotype, using control (CTL) and high-fat (HF) fed non-pregnant female mice and pregnant mice at mid- (embryonic day (E)14.5) and late (E18.5) gestation. We found that small intestine length increased between non-pregnant mice and dams at late-gestation, but ileum villus length, and ileum and colon crypt depths and goblet cell numbers remained similar. Compared to CTL-fed mice, HF-fed mice had reduced small intestine length, ileum crypt depth and villus length. Goblet cell numbers were only consistently reduced in HF-fed non-pregnant mice. Pregnancy increased in vivo gut permeability, with a greater effect at mid- versus late-gestation. Non-pregnant HF-fed mice had greater gut permeability, and permeability was also increased in HF-fed pregnant dams at mid but not late-gestation. The impaired maternal gut barrier in HF-fed dams at mid-gestation coincided with changes in maternal blood and bone marrow immune cell composition, including an expansion of circulating inflammatory Ly6Chigh monocytes. In summary, pregnancy has temporal effects on maternal intestinal structure and barrier function, and on peripheral immunophenotype, which are further modified by HF diet-induced maternal adiposity. Maternal adaptations in pregnancy are thus vulnerable to excess maternal adiposity, which may both affect maternal and child health.

Old Folks, Bad Boon: Antimicrobial Resistance in the Infant Gut Microbiome

The development of the intestinal microbiome in the neonate starts, mainly, at birth, when the infant receives its founding microbial inoculum from the mother. This microbiome contains genes conferring resistance to antibiotics since these are found in some of the microorganisms present in the intestine. Similarly to microbiota composition, the possession of antibiotic resistance genes is affected by different perinatal factors. Moreover, antibiotics are the most used drugs in early life, and the use of antibiotics in pediatrics covers a wide variety of possibilities and treatment options. The disruption in the early microbiota caused by antibiotics may be of great relevance, not just because it may limit colonization by beneficial microorganisms and increase that of potential pathogens, but also because it may increase the levels of antibiotic resistance genes. The increase in antibiotic-resistant microorganisms is one of the major public health threats that humanity has to face and, therefore, understanding the factors that determine the development of the resistome in early life is of relevance. Recent advancements in sequencing technologies have enabled the study of the microbiota and the resistome at unprecedent levels. These aspects are discussed in this review as well as some potential interventions aimed at reducing the possession of resistance genes.

Bile Acids, Intestinal Barrier Dysfunction, and Related Diseases

The intestinal barrier is a precisely regulated semi-permeable physiological structure that absorbs nutrients and protects the internal environment from infiltration of pathological molecules and microorganisms. Bile acids are small molecules synthesized from cholesterol in the liver, secreted into the duodenum, and transformed to secondary or tertiary bile acids by the gut microbiota. Bile acids interact with bile acid receptors (BARs) or gut microbiota, which plays a key role in maintaining the homeostasis of the intestinal barrier. In this review, we summarize and discuss the recent studies on bile acid disorder associated with intestinal barrier dysfunction and related diseases. We focus on the roles of bile acids, BARs, and gut microbiota in triggering intestinal barrier dysfunction. Insights for the future prevention and treatment of intestinal barrier dysfunction and related diseases are provided.

Diagnostic Value and Prognostic Significance of Nucleated Red Blood Cells (NRBCs) in Selected Medical Conditions

Nucleated red blood cells (NRBCs) are premature erythrocyte precursors that reside in the bone marrow of humans of all ages as an element of erythropoiesis. They rarely present in healthy adults' circulatory systems but can be found circulating in fetuses and neonates. An NRBC count is a cost-effective laboratory test that is currently rarely used in everyday clinical practice; it is mostly used in the diagnosis of hematological diseases/disorders relating to erythropoiesis, anemia, or hemolysis. However, according to several studies, it may be used as a biomarker in the diagnosis and clinical outcome prognosis of preterm infants or severely ill adult patients. This would allow for a quick diagnosis of life-threatening conditions and the prediction of a possible change in a patient's condition, especially in relation to patients in the intensive care unit. In this review, we sought to summarize the possible use of NRBCs as a prognostic marker in various disease entities. Research into the evaluation of the NRBCs in the pediatric population most often concerns neonatal hypoxia, the occurrence and consequences of asphyxia, and overall neonatal mortality. Among adults, NRBCs can be used to predict changes in clinical condition and mortality in critically ill patients, including those with sepsis, trauma, ARDS, acute pancreatitis, or severe cardiovascular disease.

Effect of high-fat diet on the lipid profile of ovarian granulosa cells and female reproduction in mice

Currently, comorbidities of obesity are becoming increasingly frequent. For example, obese women are more susceptible to reproductive diseases; however, the underlying mechanism remains poorly understood. The present study aimed to explore the effect of obesity on female reproduction and discuss changes of the lipid profile in ovarian granulosa cells. Fifty female mice were randomly divided into two groups, one group was fed high-fat diet, the other group was fed standard control diet, food and water freely. After 12 weeks of feeding, the average body weight of the high-fat diet mice (19.027g) was significantly higher than that of the standard control diet mice (36.877g) (P < 0.05). The tissue sections were stained with oil red O, and the online software mage Pro plus 6.0 analyzed the staining results, the lipids in the ovaries and endometria were found to be different between the two groups. Liquid chromatography-electrospray ionization with tandem mass spectrometry (LC-ESI-MS/MS) analysis of ovarian granulosa cells (GCs) was performed, with a total of 228 different lipids being identified, the abundant of 147 were increased and 81 were decreased in the high-fat diet group. Among them, PI (18:1/20:1) was the most different lipid, and high-fat feeding was 85 times higher than standard control group. Among these different lipids, 44% in phospholipid metabolism, 30% in glycerolipid metabolism, and 30% in fat digestion and absorption. The results of this study laid a theoretical foundation of the effects of diet-induced obesity on female reproduction.

Significant Microbial Changes Are Evident in the Reproductive Tract of Pregnant Rhesus Monkeys at Mid-Gestation but Their Gut Microbiome Does Not Shift until Late Gestation

Vaginal and rectal specimens were obtained from cycling, pregnant, and nursing rhesus monkeys to assess pregnancy-related changes in the commensal bacteria in their reproductive and intestinal tracts. Using 16S rRNA gene amplicon sequencing, significant differences were found only in the vagina at mid-gestation, not in the hindgut. To verify the apparent stability in gut bacterial composition at mid-gestation, the experiment was repeated with additional monkeys, and similar results were found with both 16S rRNA gene amplicon and metagenomic sequencing. A follow-up study investigated if bacterial changes in the hindgut might occur later in pregnancy. Gravid females were assessed closer to term and compared to nonpregnant females. By late pregnancy, significant differences in bacterial composition, including an increased abundance of 4 species of Lactobacillus and Bifidobacterium adolescentis, were detected, but without a shift in the overall community structure. Progesterone levels were assessed as a possible hormone mediator of bacterial change. The relative abundance of only some taxa (e.g., Bifidobacteriaceae) were specifically associated with progesterone. In summary, pregnancy changes the microbial profiles in monkeys, but the bacterial diversity in their lower reproductive tract is different from women, and the composition of their intestinal symbionts remains stable until late gestation when several Firmicutes become more prominent.

Molecular mechanisms involved in fetal programming and disease origin in adulthood

Fetal programming occurs during the gestational age when exposure to environmental stimuli can cause long-term changes in the fetus, predisposing it to develop chronic non-communicable diseases (CNCD) in adulthood. Herein, we summarized the role of low-calorie or high-fat diets during pregnancy as fetal programming agents that induce intrauterine growth restriction (IUGR), amplified de novo lipogenesis, and increased amino acid transport to the placenta, which favor the CNCD onset in the offspring. We also outlined how maternal obesity and gestational diabetes act as fetal programming stimuli by reducing iron absorption and oxygen transport to the fetus, stimulating inflammatory pathways that boost neurological disorders and CNCD in the progeny. Moreover, we reviewed the mechanisms through which fetal hypoxia elevates the offspring's risk of developing hypertension and chronic kidney disease in adult life by unbalancing the renin-angiotensin system and promoting kidney cell apoptosis. Finally, we examined how inadequate vitamin B12 and folic acid consumption during pregnancy programs the fetus to greater adiposity, insulin resistance, and glucose intolerance in adulthood. A better understanding of the fetal programming mechanisms may help us reduce the onset of insulin resistance, glucose intolerance, dyslipidemia, obesity, hypertension, diabetes mellitus, and other CNCD in the offspring during adulthood.

Impact of high-fat diet consumption during prolonged period of pregnancy on placenta structures and umbilical vascular growth in goats

This study aimed to verify the impact of high-fat diet consumption for a prolonged period on oxidative stress, fetal growth, umbilical vascular system, and placental structures in pregnant goats. Twenty-two pregnant goats were grouped into the control diet (n= 11) and fat diet (n = 11). Flaxseed meal was added to the fat diet, replacing the corn grain of concentrate, from gestational day 100 to delivery date. Diets were isonitrogenous and isoenergetic, differing in fat content (2.8% vs. 6.3% dry matter). The fat group showed higher feed intake and total plasma lipid levels than the control group (P < 0.001). No difference was found in placentome, and umbilical vascular development. Fat diet-fed goats exhibited a lower systolic peak in the umbilical artery. At delivery, placental traits were similar with the exception of the cotyledon width (P = 0.0075), which was smaller in the fat group and cotyledon surface (P = 0.0047) for multiple pregnancy of fat diet. Cotyledonary epithelium showed more intense staining of lipid droplets and a greater area for lipofuscin staining in the fat group compared to control group (P < 0.001). The mean live weight of the kids was lower in the fat group in the first week after delivery than in control group. Thus, in goats, the continuous administration of a high-fat diet during pregnancy does not appear to modify the fetal-maternal vascular structures but has an impact on a part of the placental structure; therefore, its use must be carefully evaluated.

Maternal high-fat diet increases the susceptibility of offspring to colorectal cancer via the activation of intestinal inflammation

A high-fat diet plays a key role in the pathogenesis of colorectal cancer, and this effect on the gut can also occur in the offspring of mothers with a high-fat diet. In this review, we discuss the role of a high-fat diet in the pathogenesis of colorectal cancer and summarize the effects of a maternal high-fat diet on the activation of inflammation and development of colorectal cancer in offspring. Studies have found that a maternal high-fat diet primarily induces an inflammatory response in the colorectal tissue of both the mother herself and the offspring during pregnancy. This leads to the accumulation of inflammatory cells in the colorectal tissue and the release of inflammatory cytokines, which further activate the NF-κb and related inflammatory signaling pathways. Research suggests that high levels of lipids and inflammatory factors from mothers with a high-fat diet are passed to the offspring through the transplacental route, which induces colorectal inflammation, impairs the intestinal microecological structure and the intestinal barrier, and interferes with intestinal development in the offspring. This in turn activates the NF-κb and related signaling pathways, which further aggravates intestinal inflammation. This process of continuous inflammatory stimulation and repair may promote the uncontrolled proliferation of colorectal mucosal cells in the offspring, thus increasing their susceptibility to colorectal cancer.

Mechanisms of Maternal Diet-Induced Obesity Affecting the Offspring Brain and Development of Affective Disorders

Depression and metabolic disease are common disorders that share a bidirectional relationship and continue to increase in prevalence. Maternal diet and maternal behaviour both profoundly influence the developmental trajectory of offspring during the perinatal period. At an epidemiological level, both maternal depression and obesity during pregnancy have been shown to increase the risk of neuropsychiatric disease in the subsequent generation. Considerable progress has been made to understand the mechanisms by which maternal obesity disrupts the developing offspring gut-brain axis, priming offspring for the development of affective disorders. This review outlines such mechanisms in detail, including altered maternal care, the maternal microbiome, inflammation, breast milk composition, and maternal and placental metabolites. Subsequently, offspring may be prone to developing gut-brain interaction disorders with concomitant changes to brain energy metabolism, neurotransmission, and behaviour, alongside gut dysbiosis. The gut microbiome may act as a key modifiable, and therefore treatable, feature of the relationship between maternal obesity and the offspring brain function. Further studies examining the relationship between maternal nutrition, the maternal microbiome and metabolites, and offspring neurodevelopment are warranted to identify novel therapeutic targets.

Cannabidiol treatment improves metabolic profile and decreases hypothalamic inflammation caused by maternal obesity

Introduction

The implications of maternal overnutrition on offspring metabolic and neuroimmune development are well-known. Increasing evidence now suggests that maternal obesity and poor dietary habits during pregnancy and lactation can increase the risk of central and peripheral metabolic dysregulation in the offspring, but the mechanisms are not sufficiently established. Furthermore, despite many studies addressing preventive measures targeted at the mother, very few propose practical approaches to treat the damages when they are already installed.

Methods

Here we investigated the potential of cannabidiol (CBD) treatment to attenuate the effects of maternal obesity induced by a cafeteria diet on hypothalamic inflammation and the peripheral metabolic profile of the offspring in Wistar rats.

Results

We have observed that maternal obesity induced a range of metabolic imbalances in the offspring in a sex-dependant manner, with higher deposition of visceral white adipose tissue, increased plasma fasting glucose and lipopolysaccharides (LPS) levels in both sexes, but the increase in serum cholesterol and triglycerides only occurred in females, while the increase in plasma insulin and the homeostatic model assessment index (HOMA-IR) was only observed in male offspring. We also found an overexpression of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNFα), interleukin (IL) 6, and interleukin (IL) 1β in the hypothalamus, a trademark of neuroinflammation. Interestingly, the expression of GFAP, a marker for astrogliosis, was reduced in the offspring of obese mothers, indicating an adaptive mechanism to in utero neuroinflammation. Treatment with 50 mg/kg CBD oil by oral gavage was able to reduce white adipose tissue and revert insulin resistance in males, reduce plasma triglycerides in females, and attenuate plasma LPS levels and overexpression of TNFα and IL6 in the hypothalamus of both sexes.

Discussion

Together, these results indicate an intricate interplay between peripheral and central counterparts in both the pathogenicity of maternal obesity and the therapeutic effects of CBD. In this context, the impairment of internal hypothalamic circuitry caused by neuroinflammation runs in tandem with the disruptions of important metabolic processes, which can be attenuated by CBD treatment in both ends.

Gut bacterial species in late trimester of pregnant sows influence the occurrence of stillborn piglet through pro-inflammation response

Maternal gut microbiota is an important regulator for the metabolism and immunity of the fetus during pregnancy. Recent studies have indicated that maternal intestinal microbiota is closely linked to the development of fetus and infant health. Some bacterial metabolites are considered to be directly involved in immunoregulation of fetus during pregnancy. However, the detailed mechanisms are largely unknown. In this study, we exploited the potential correlation between the gut microbiota of pregnant sows and the occurrence of stillborn piglets by combining the 16S rRNA gene and metagenomic sequencing data, and fecal metabolome in different cohorts. The results showed that several bacterial species from Bacteroides, potential pathogens, and LPS-producing bacteria exhibited significantly higher abundances in the gut of sows giving birth to stillborn piglets. Especially, Bacteroides fragilis stood out as the key driver in both tested cohorts and showed the most significant association with the occurrence of stillborn piglets in the DN1 cohort. However, several species producing short-chain fatty acids (SCFAs), such as Prevotella copri, Clostridium butyricum and Faecalibacterium prausnitzii were enriched in the gut of normal sows. Functional capacity analysis of gut microbiome revealed that the pathways associated with infectious diseases and immune diseases were enriched in sows giving birth to stillborn piglets. However, energy metabolism had higher abundance in normal sows. Fecal metabolome profiling analysis found that Lysophosphatidylethanolamine and phosphatidylethanolamine which are the main components of cell membrane of Gram-negative bacteria showed significantly higher concentration in stillbirth sows, while SCFAs had higher concentration in normal sows. These metabolites were significantly associated with the stillborn-associated bacterial species including Bacteroides fragilis. Lipopolysaccharide (LPS), IL-1β, IL-6, FABP2, and zonulin had higher concentration in the serum of stillbirth sows, indicating increased intestinal permeability and pro-inflammatory response. The results from this study suggested that certain sow gut bacterial species in late trimester of pregnancy, e.g., an excess abundance of Bacteroides fragilis, produced high concentration of LPS which induced sow pro-inflammatory response and might cause the death of the relatively weak piglets in a farrow. This study provided novel evidences about the effect of maternal gut microbiota on the fetus development and health.

Supplementation of Methyl-Donor Nutrients to a High-Fat, High-Sucrose Diet during Pregnancy and Lactation Normalizes Circulating 25-Dihydroxycholecalciferol Levels and Alleviates Inflammation in Offspring

A Western-style diet that is high in fat and sucrose has been shown to alter DNA methylation and epigenetically modify genes related to health risk in offspring. Here, we investigated the effect of a methyl-donor nutrient (MS) supplemented to a high-fat, high-sucrose (HFS) diet during pregnancy and lactation on vitamin D (VD) status and inflammatory response in offspring. After mating, 10-week-old female Sprague-Dawley (SD) rats (n = 10/group) were randomly assigned to one of the four dietary groups during pregnancy and lactation: (1) control diet (CON), (2) CON with MS (CON-MS), (3) HFS, and (4) HFS with MS (HFS-MS). Weanling offspring (three weeks old) were euthanized and sacrificed (n = 8-10/sex/group). The remaining offspring (n = 10/sex/group) were randomly assigned to either a CON or an HFS diet for 12 weeks and sacrificed at 15 weeks of age. Our results indicated that prenatal MS supplementation, but not postnatal diet, restored low vitamin D status and suppressed elevation of proinflammatory cytokine induced by maternal HFS in the offspring. Furthermore, both prenatal and postnatal diets modulated the abundance of Lactobacillus spp. and Bacteroides spp. in the offspring, a shift that was independent of vitamin D status. Collectively, our data support a role for MS in restoring the perturbation of VD status and normalizing maternal HFS-induced inflammation in the offspring. Further investigation is warranted to elucidate the methylation status of VD metabolism-related pathways in the offspring, as well as the immunomodulatory role of vitamin D during the progression of obesity.

Puerariae lobatae Radix Alleviates Pre-Eclampsia by Remodeling Gut Microbiota and Protecting the Gut and Placental Barriers

Pre-eclampsia (PE) is a serious pregnancy complication, and gut dysbiosis is an important cause of it. Puerariae lobatae Radix (PLR) is a medicine and food homologous species; however, its effect on PE is unclear. This study aimed to investigate the efficacy of PLR in alleviating PE and its mechanisms. We used an NG-nitro-L-arginine methyl ester (L-NAME)-induced PE mouse model to examine the efficacy of preventive and therapeutic PLR supplementation. The results showed that both PLR interventions alleviated hypertension and proteinuria, increased fetal and placental weights, and elevated the levels of VEGF and PlGF. Moreover, PLR protected the placenta from oxidative stress via activating the Nrf2/HO-1/NQO1 pathway and mitigated placental damage by increasing intestinal barrier markers (ZO-1, Occludin, and Claudin-1) expression and reducing lipopolysaccharide leakage. Notably, preventive PLR administration corrected gut dysbiosis in PE mice, as evidenced by the increased abundance and positive interactions of beneficial bacteria including Bifidobacterium, Blautia, and Turicibacter. Fecal microbiota transplantation confirmed that the gut microbiota partially mediated the beneficial effects of PLR on PE. Our findings revealed that modulating the gut microbiota is an effective strategy for the treatment of PE and highlighted that PLR might be used as an intestinal nutrient supplement in PE patients.

Maternal gut microbiota mediate intergenerational effects of high-fat diet on descendant social behavior

Dysbiosis of the maternal gut microbiome during pregnancy is associated with adverse neurodevelopmental outcomes. We previously showed that maternal high-fat diet (MHFD) in mice induces gut dysbiosis, social dysfunction, and underlying synaptic plasticity deficits in male offspring (F₁). Here, we reason that, if HFD-mediated changes in maternal gut microbiota drive offspring social deficits, then MHFD-induced dysbiosis in F₁ female MHFD offspring would likewise impair F₂ social behavior. Metataxonomic sequencing reveals reduced microbial richness among female F₁ MHFD offspring. Despite recovery of microbial richness among MHFD-descendant F₂ mice, they display social dysfunction. Post-weaning Limosilactobacillus reuteri treatment increases the abundance of short-chain fatty acid-producing taxa and rescues MHFD-descendant F₂ social deficits. L. reuteri exerts a sexually dimorphic impact on gut microbiota configuration, increasing discriminant taxa between female cohorts. Collectively, these results show multigenerational impacts of HFD-induced dysbiosis in the maternal lineage and highlight the potential of maternal microbiome-targeted interventions for neurodevelopmental disorders.

Maternal obesity: new placental paradigms unfolded

The prevalence of maternal obesity is increasing at an alarming rate, and is providing a major challenge for obstetric practice. Adverse effects on maternal and fetal health are mediated by complex interactions between metabolic, inflammatory, and oxidative stress signaling in the placenta. Endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR) are common downstream pathways of cell stress, and there is evidence that this conserved homeostatic response may be a key mediator in the pathogenesis of placental dysfunction. We summarize the current literature on the placental cellular and molecular changes that occur in obese women. A special focus is cast onto placental ER stress in obese pregnancy, which may provide a novel link for future investigation.

The impact of maternal high-fat diet on offspring neurodevelopment

A maternal high-fat diet affects offspring neurodevelopment with long-term consequences on their brain health and behavior. During the past three decades, obesity has rapidly increased in the whole human population worldwide, including women of reproductive age. It is known that maternal obesity caused by a high-fat diet may lead to neurodevelopmental disorders in their offspring, such as autism spectrum disorder, attention deficit hyperactivity disorder, anxiety, depression, and schizophrenia. A maternal high-fat diet can affect offspring neurodevelopment due to inflammatory activation of the maternal gut, adipose tissue, and placenta, mirrored by increased levels of pro-inflammatory cytokines in both maternal and fetal circulation. Furthermore, a maternal high fat diet causes gut microbial dysbiosis further contributing to increased inflammatory milieu during pregnancy and lactation, thus disturbing both prenatal and postnatal neurodevelopment of the offspring. In addition, global molecular and cellular changes in the offspring's brain may occur due to epigenetic modifications including the downregulation of brain-derived neurotrophic factor (BDNF) expression and the activation of the endocannabinoid system. These neurodevelopmental aberrations are reflected in behavioral deficits observed in animals, corresponding to behavioral phenotypes of certain neurodevelopmental disorders in humans. Here we reviewed recent findings from rodent models and from human studies to reveal potential mechanisms by which a maternal high-fat diet interferes with the neurodevelopment of the offspring.

The Therapeutic Effect of SCFA-Mediated Regulation of the Intestinal Environment on Obesity

Intestinal environment disorder is a potential pathological mechanism of obesity. There is increasing evidence that disorders in the homeostasis of the intestinal environment can affect various metabolic organs, such as fat and liver, and lead to metabolic diseases. However, there are few therapeutic approaches for obesity targeting the intestinal environment. In this review, on the one hand, we discuss how intestinal microbial metabolites SCFA regulate intestinal function to improve obesity and the possible mechanisms and pathways related to obesity-related pathological processes (depending on SCFA-related receptors such as GPCRs, MCT and SMCT, and through epigenetic processes). On the other hand, we discuss dietary management strategies to enrich SCFA-producing bacteria and target specific SCFA-producing bacteria and whether fecal bacteria transplantation therapy to restore the composition of the gut microbiota to regulate SCFA can help prevent or improve obesity. Finally, we believe that it will be of great significance to establish a working model of gut– SCFA– metabolic disease development in the future for the improvement this human health concern.

Diet Modification before or during Pregnancy on Maternal and Foetal Outcomes in Rodent Models of Maternal Obesity

The obesity epidemic has serious implications for women of reproductive age; its rising incidence is associated not just with health implications for the mother but also has transgenerational ramifications for the offspring. Increased incidence of diabetes, cardiovascular disease, obesity, and kidney disease are seen in both the mothers and the offspring. Animal models, such as rodent studies, are fundamental to studying maternal obesity and its impact on maternal and offspring health, as human studies lack rigorous controlled experimental design. Furthermore, the short and prolific reproductive potential of rodents enables examination across multiple generations and facilitates the exploration of interventional strategies to mitigate the impact of maternal obesity, both before and during pregnancy. Given that obesity is a major public health concern, it is important to obtain a greater understanding of its pathophysiology and interaction with reproductive health, placental physiology, and foetal development. This narrative review focuses on the known effects of maternal obesity on the mother and the offspring, and the benefits of interventional strategies, including dietary intervention, before or during pregnancy on maternal and foetal outcomes. It further examines the contribution of rodent models of maternal obesity to elucidating pathophysiological pathways of disease development, as well as methods to reduce the impact of obesity on the mothers and the developing foetus. The translation of these findings into the human experience will also be discussed.

Gestational Insulin Resistance Is Mediated by the Gut Microbiome-Indoleamine 2,3-Dioxygenase Axis

BACKGROUND & AIMS

Normal gestation involves a reprogramming of the maternal gut microbiome (GM) that contributes to maternal metabolic changes by unclear mechanisms. This study aimed to understand the mechanistic underpinnings of the GM-maternal metabolism interaction.

METHODS

The GM and plasma metabolome of CD1, NIH-Swiss, and C57 mice were analyzed with the use of 16S rRNA sequencing and untargeted liquid chromatography-mass spectrometry throughout gestation. Pharmacologic and genetic knockout mouse models were used to identify the role of indoleamine 2,3-dioxygenase (IDO1) in pregnancy-associated insulin resistance (IR). Involvement of gestational GM was studied with the use of fecal microbial transplants (FMTs).

RESULTS

Significant variation in GM alpha diversity occurred throughout pregnancy. Enrichment in gut bacterial taxa was mouse strain and pregnancy time point specific, with the species enriched at gestation day 15/19 (G15/19), a point of heightened IR, being distinct from those enriched before or after pregnancy. Metabolomics revealed elevated plasma kynurenine at G15/19 in all 3 mouse strains. IDO1, the rate-limiting enzyme for kynurenine production, had increased intestinal expression at G15, which was associated with mild systemic and gut inflammation. Pharmacologic and genetic inhibition of IDO1 inhibited kynurenine levels and reversed pregnancy-associated IR. FMT revealed that IDO1 induction and local kynurenine level effects on IR derive from the GM in both mouse and human pregnancy.

CONCLUSIONS

GM changes accompanying pregnancy shift IDO1-dependent tryptophan metabolism toward kynurenine production, intestinal inflammation, and gestational IR, a phenotype reversed by genetic deletion or inhibition of IDO1. (Gestational Gut Microbiome-IDO1 Axis Mediates Pregnancy Insulin Resistance; EMBL-ENA ID: PRJEB45047. MetaboLights ID: MTBLS3598).

Maternal High-Fat Diet Impairs Placental Fatty Acid β-Oxidation and Metabolic Homeostasis in the Offspring

Maternal overnutrition can affect fetal growth and development, thus increasing susceptibility to obesity and diabetes in later life of the offspring. Placenta is the central organ connecting the developing fetus with the maternal environment. It is indicated placental fatty acid metabolism plays an essential role in affecting the outcome of the pregnancy and fetus. However, the role of placental fatty acid β-oxidation (FAO) in maternal overnutrition affecting glucose metabolism in the offspring remains unclear. In this study, C57BL/6J female mice were fed with normal chow or high-fat diet before and during pregnancy and lactation. The placenta and fetal liver were collected at gestation day 18.5, and the offspring's liver was collected at weaning. FAO-related genes and AMP-activated protein kinase (AMPK) signaling pathway were examined both in the placenta and in the human JEG-3 trophoblast cells. FAO-related genes were further examined in the liver of the fetuses and in the offspring at weaning. We found that dams fed with high-fat diet showed higher fasting blood glucose, impaired glucose tolerance at gestation day 14.5 and higher serum total cholesterol (T-CHO) at gestation day 18.5. The placental weight and lipid deposition were significantly increased in maternal high-fat diet group. At weaning, the offspring mice of high-fat diet group exhibited higher body weight, impaired glucose tolerance, insulin resistance and increased serum T-CHO, compared with control group. We further found that maternal high-fat diet downregulated mRNA and protein expressions of carnitine palmitoyltransferase 2 (CPT2), a key enzyme in FAO, by suppressing the AMPK/Sirt1/PGC1α signaling pathway in the placenta. In JEG-3 cells, protein expressions of CPT2 and CPT1b were both downregulated by suppressing the AMPK/Sirt1/PGC1α signaling pathway under glucolipotoxic condition, but were later restored by the AMPK agonist 5-aminoimidazole-4-carboxyamide ribonucleoside (AICAR). However, there was no difference in CPT2 and CPT1 gene expression in the liver of fetuses and offspring at weaning age. In conclusion, maternal high-fat diet can impair gene expression involved in FAO in the placenta by downregulating the AMPK signaling pathway, and can cause glucose and lipid dysfunction of offspring at weaning, indicating that placental FAO may play a crucial role in regulating maternal overnutrition and metabolic health in the offspring.

Gut microbiota in gastrointestinal diseases during pregnancy

Gut microbiota (GM) is a micro-ecosystem composed of all microorganisms in the human intestine. The interaction between GM and the host plays an important role in maintaining normal physiological functions in the host. Dysbiosis of the GM may cause various diseases. GM has been demonstrated to be associated with human health and disease, and changes during individual development and disease. Pregnancy is a complicated physiological process. Hormones, the immune system, metabolism, and GM undergo drastic changes during pregnancy. Gastrointestinal diseases during pregnancy, such as hepatitis, intrahepatic cholestasis of pregnancy, and pre-eclampsia, can affect both maternal and fetal health. The dysregulation of GM during pregnancy may lead to a variety of diseases, including gastrointestinal diseases. Herein, we review recent research articles on GM in pregnancy-related gastrointestinal diseases, discuss the interaction of the GM with the host under normal physiological conditions, gastrointestinal diseases, and pregnancy-specific disorders. As more attention is paid to reproductive health, the pathogenic mechanism of GM in gastrointestinal diseases during pregnancy will be further studied to provide a theoretical basis for the use of probiotics to treat these diseases.

Paternal obesity induces placental hypoxia and sex-specific impairments in placental vascularization and offspring metabolism

Paternal obesity predisposes offspring to metabolic dysfunction, but the underlying mechanisms remain unclear. We investigated whether this metabolic dysfunction is associated with changes in placental vascular development and is fueled by endoplasmic reticulum (ER) stress-mediated changes in fetal hepatic development. We also determined whether paternal obesity indirectly affects the in utero environment by disrupting maternal metabolic adaptations to pregnancy. Male mice fed a standard chow or high fat diet (60%kcal fat) for 8–10 weeks were time-mated with female mice to generate pregnancies and offspring. Glucose tolerance was evaluated in dams at mid-gestation (embryonic day (E) 14.5) and late gestation (E18.5). Hypoxia, angiogenesis, endocrine function, macronutrient transport, and ER stress markers were evaluated in E14.5 and E18.5 placentae and/or fetal livers. Maternal glucose tolerance was assessed at E14.5 and E18.5. Metabolic parameters were assessed in offspring at ~60 days of age. Paternal obesity did not alter maternal glucose tolerance but induced placental hypoxia and altered placental angiogenic markers, with the most pronounced effects in female placentae. Paternal obesity increased ER stress-related protein levels (ATF6 and PERK) in the fetal liver and altered hepatic expression of gluconeogenic factors at E18.5. Offspring of obese fathers were glucose intolerant and had impaired whole-body energy metabolism, with more pronounced effects in female offspring. Metabolic deficits in offspring due to paternal obesity may be mediated by sex-specific changes in placental vessel structure and integrity that contribute to placental hypoxia and may lead to poor fetal oxygenation and impairments in fetal metabolic signaling pathways in the liver.

Heat Stress Modulates a Placental Immune Response Associated With Alterations in the Development of the Fetal Intestine and Its Innate Immune System in Late Pregnant Mouse

The placenta is critical for the regulation of fetal innate immune function. Maternal heat stress (HS) impairs the immune function and the intestinal barrier in the offspring. However, the effects of maternal HS on the placental immune response and the development of the fetal intestine and its innate immune system remain unclear. Fetal mice were divided into the utero control (IUTN) and heat stress (IUHS) groups according to the maternal ambient temperature. Transcriptome analysis revealed that the expressions of placental immune response–related genes such as macrophage antigen CD68 and Fc gamma receptors 1 and 3 (fcgγ1 and fcgγ3) were increased, but the mRNA expression and protein levels of colony-stimulating factor-1 (Csf1) were decreased in the HS group compared with the TN group (p < 0.05). Furthermore, there was no significant difference in the intestinal length normalized to pup weight between the IUTN and IUHS groups. The expression of genes (such as alpi and ttr) involved in fetal duodenum and jejunum development was downregulated by maternal HS, whereas the expression of genes enriched in the cell cycle was increased. The mRNA expression and protein levels of cell division cycle 6 (Cdc6) in the fetal duodenum and jejunum were much higher in the IUHS group than in the IUTN group (p < 0.05). Maternal HS also down-regulated the expression of genes enriched in the innate immune system in the fetal duodenum and jejunum. The mRNA expression and protein levels of interleukin 1 alpha (IL1a) were reduced in the IUHS group compared with the IUTN group (p < 0.05). Taken together, these data demonstrated that maternal HS modulated the expression of genes in the placenta related to the immune response and inhibited the development of the fetal intestine and its innate immune system.

The intestine and the microbiota in maternal glucose homeostasis during pregnancy

It is now well established that, beyond its role in nutrient processing and absorption, the intestine and its accompanying gut microbiome constitute a major site of immunological and endocrine regulation that mediates whole-body metabolism. Despite the growing field of host-microbe research, few studies explore what mechanisms govern this relationship in the context of pregnancy. During pregnancy, significant maternal metabolic adaptations are made to accommodate the additional energy demands of the developing fetus and to prevent adverse pregnancy outcomes. Recent data suggest that the maternal gut microbiota may play a role in these adaptations, but changes to maternal gut physiology and the underlying intestinal mechanisms remain unclear. In this review, we discuss selective aspects of intestinal physiology including the role of the incretin hormone, glucagon-like peptide 1 (GLP-1), and the role of the maternal gut microbiome in the maternal metabolic adaptations to pregnancy. Specifically, we discuss how bacterial components and metabolites could mediate the effects of the microbiota on host physiology, including nutrient absorption and GLP-1 secretion and action, and whether these mechanisms may change maternal insulin sensitivity and secretion during pregnancy. Finally, we discuss how these pathways could be altered in disease states during pregnancy including maternal obesity and diabetes.

Maternal Obesity Related to High Fat Diet Induces Placenta Remodeling and Gut Microbiome Shaping That Are Responsible for Fetal Liver Lipid Dysmetabolism

Background: Maternal obesity in utero may affect fetal development and cause metabolic problems during childhood and even adulthood. Diet-induced maternal obesity can impair gut barrier integrity and change the gut microbiome, which may contribute to adverse placental adaptations and increase the obesity risk in offspring. However, the mechanism through which maternal obesity causes offspring metabolic disorder must be identified.

Methods: Eight-week-old female rats received a control diet or high-fat (HF) diet for 11 weeks before conception and during gestation. The placentas were collected on gestational day 21 before offspring delivery. Placental tissues, gut microbiome, and short-chain fatty acids of dams and fetal liver tissues were studied.

Results: Maternal HF diet and obesity altered the placental structure and metabolism-related transcriptome and decreased G protein–coupled receptor 43 expression. HF diet and obesity also changed the gut microbiome composition and serum propionate level of dams. The fetal liver exhibited steatosis, enhanced oxidative stress, and increased expression of acetyl-CoA carboxylase 1 and lipoprotein lipase with changes in maternal HF diet and obesity.

Conclusions: Maternal HF diet and obesity shape gut microbiota and remodel the placenta of dams, resulting in lipid dysmetabolism of the fetal liver, which may ultimately contribute to the programming of offspring obesity.

Western diet-induced shifts in the maternal microbiome are associated with altered microRNA expression in baboon placenta and fetal liver

Maternal consumption of a high-fat, Western-style diet (WD) disrupts the maternal/infant microbiome and contributes to developmental programming of the immune system and nonalcoholic fatty liver disease (NAFLD) in the offspring. Epigenetic changes, including non-coding miRNAs in the fetus and/or placenta may also underlie this risk. We previously showed that obese nonhuman primates fed a WD during pregnancy results in the loss of beneficial maternal gut microbes and dysregulation of cellular metabolism and mitochondrial dysfunction in the fetal liver, leading to a perturbed postnatal immune response with accelerated NAFLD in juvenile offspring. Here, we investigated associations between WD-induced maternal metabolic and microbiome changes, in the absence of obesity, and miRNA and gene expression changes in the placenta and fetal liver. After ~8-11 months of WD feeding, dams were similar in body weight but exhibited mild, systemic inflammation (elevated CRP and neutrophil count) and dyslipidemia (increased triglycerides and cholesterol) compared with dams fed a control diet. The maternal gut microbiome was mainly comprised of Lactobacillales and Clostridiales, with significantly decreased alpha diversity (P = 0.0163) in WD-fed dams but no community-wide differences (P = 0.26). At 0.9 gestation, mRNA expression of IL6 and TNF in maternal WD (mWD) exposed placentas trended higher, while increased triglycerides, expression of pro-inflammatory CCR2, and histological evidence for fibrosis were found in mWD-exposed fetal livers. In the mWD-exposed fetus, hepatic expression levels of miR-204-5p and miR-145-3p were significantly downregulated, whereas in mWD-exposed placentas, miR-182-5p and miR-183-5p were significantly decreased. Notably, miR-1285-3p expression in the liver and miR-183-5p in the placenta were significantly associated with inflammation and lipid synthesis pathway genes, respectively. Blautia and Ruminococcus were significantly associated with miR-122-5p in liver, while Coriobacteriaceae and Prevotellaceae were strongly associated with miR-1285-3p in the placenta; both miRNAs are implicated in pathways mediating postnatal growth and obesity. Our findings demonstrate that mWD shifts the maternal microbiome, lipid metabolism, and inflammation prior to obesity and are associated with epigenetic changes in the placenta and fetal liver. These changes may underlie inflammation, oxidative stress, and fibrosis patterns that drive NAFLD and metabolic disease risk in the next generation.

Epigenetic Modifications at the Center of the Barker Hypothesis and Their Transgenerational Implications

Embryo/fetal nutrition and the environment in the reproductive tract influence the subsequent risk of developing adult diseases and disorders, as formulated in the Barker hypothesis. Metabolic syndrome, obesity, heart disease, and hypertension in adulthood have all been linked to unwanted epigenetic programing in embryos and fetuses. Multiple studies support the conclusion that environmental challenges, such as a maternal low-protein diet, can change one-carbon amino acid metabolism and, thus, alter histone and DNA epigenetic modifications. Since histones influence gene expression and the program of embryo development, these epigenetic changes likely contribute to the risk of adult disease onset not just in the directly affected offspring, but for multiple generations to come. In this paper, we hypothesize that the effects of parental nutritional status on fetal epigenetic programming are transgenerational and warrant further investigation. Numerous studies supporting this hypothesis are reviewed, and potential research techniques to study these transgenerational epigenetic effects are offered.

Microbiome Crosstalk in Immunotherapy and Antiangiogenesis Therapy

The human body and its microbiome constitute a highly delicate system. The gut microbiome participates in the absorption of the host's nutrients and metabolism, maintains the microcirculation, and modulates the immune response. Increasing evidence shows that gut microbiome dysbiosis in the body not only affects the occurrence and development of tumors but also tumor prognosis and treatment. Microbiome have been implicated in tumor control in patients undergoing anti- angiogenesis therapy and immunotherapy. In cases with unsatisfactory responses to chemotherapy, radiotherapy, and targeted therapy, appropriate adjustment of microbes abundance is considered to enhance the treatment response. Here, we review the current research progress in cancer immunotherapy and anti- angiogenesis therapy, as well as the unlimited potential of their combination, especially focusing on how the interaction between intestinal microbiota and the immune system affects cancer pathogenesis and treatment. In addition, we discuss the effects of microbiota on anti-cancer immune response and anti- angiogenesis therapy, and the potential value of these interactions in promoting further research in this field.

The composition of human vaginal microbiota transferred at birth affects offspring health in a mouse model

Newborns are colonized by maternal microbiota that is essential for offspring health and development. The composition of these pioneer communities exhibits individual differences, but the importance of this early-life heterogeneity to health outcomes is not understood. Here we validate a human microbiota-associated model in which fetal mice are cesarean delivered and gavaged with defined human vaginal microbial communities. This model replicates the inoculation that occurs during vaginal birth and reveals lasting effects on offspring metabolism, immunity, and the brain in a community-specific manner. This microbial effect is amplified by prior gestation in a maternal obesogenic or vaginal dysbiotic environment where placental and fetal ileum development are altered, and an augmented immune response increases rates of offspring mortality. Collectively, we describe a translationally relevant model to examine the defined role of specific human microbial communities on offspring health outcomes, and demonstrate that the prenatal environment dramatically shapes the postnatal response to inoculation.

Metabolomics to understand placental biology: Where are we now?

Metabolomics, the application of analytical chemistry methodologies to survey the chemical composition of a biological system, is used to globally profile and compare metabolites in one or more groups of samples. Given that metabolites are the terminal end-products of cellular metabolic processes, or 'phenotype' of a cell, tissue, or organism, metabolomics is valuable to the study of the maternal-fetal interface as it has the potential to reveal nuanced complexities of a biological system as well as differences over time or between individuals. The placenta acts as the primary site of maternal-fetal exchange, the success of which is paramount to growth and development of offspring during pregnancy and beyond. Although the study of metabolomics has proven moderately useful for the screening, diagnosis, and understanding of the pathophysiology of pregnancy complications, the placental metabolome in the context of a healthy pregnancy remains poorly characterized and understood. Herein, we discuss the technical aspects of metabolomics and review the current literature describing the placental metabolome in human and animal models, in the context of health and disease. Finally, we highlight areas for future opportunities in the emerging field of placental metabolomics.

Sodium butyrate alleviates pre-eclampsia in pregnant rats by improving the gut microbiota and short-chain fatty acid metabolites production

AIMS

Pre-eclampsia (PE) affects pregnant patients worldwide, but there is no effective treatment for this condition. We aimed to explore the effect of sodium butyrate (NaB) on PE.

METHODS AND RESULTS

In this study, Nω-nitro-L-arginine methyl ester hydrochloride was used to induce PE in pregnant rats. We found that NaB significantly decreased the levels of blood pressure, 24-h protein urine and inflammatory factors (IL-1β, IL-6 and TGF-β), increased the foetal and placental weights and intestinal barrier markers (ZO-1, claudin-5 and occludin) expression. In addition, NaB intervention reduced the levels of soluble fms-like tyrosine kinase 1 and soluble endoglin and increased placental growth factor level. Meanwhile, after NaB treatment, the Treg/Th17 ratio of immune cells in the spleen and small intestine of pregnant rats decreased, while the level of pregnancy-related diamine oxidase increased. Notably, the PE rat treatment with NaB improved gut microbiota compositions, especially for the abundances of Firmicutes and Bacteroides, and significantly increased butyric acid and pentanoic acid levels, which might help to alleviate PE in pregnant rats.

CONCLUSION

In the PE rat model, exogenous NaB improved intestinal barrier function and reduced adverse outcomes, which might be associated with the gut microbiota and its production of SCFA metabolites.

SIGNIFICANCE AND IMPACT OF THE STUDY

NaB might alleviate the adverse outcomes of PE by regulating gut microbiota and its metabolite SCFA, which revealed that NaB might be a potential regulator of gut microbiota and a therapeutic substance for PE.

Effects of Maternal Obesity On Placental Phenotype

The incidence of obesity is rising rapidly worldwide with the consequence that more women are entering pregnancy overweight or obese. This leads to an increased incidence of clinical complications during pregnancy and of poor obstetric outcomes. The offspring of obese pregnancies are often macrosomic at birth although there is also a subset of the progeny that are growth-restricted at term. Maternal obesity during pregnancy is also associated with cardiovascular, metabolic and endocrine dysfunction in the offspring later in life. As the interface between the mother and fetus, the placenta has a central role in programming intrauterine development and is known to adapt its phenotype in response to environmental conditions such as maternal undernutrition and hypoxia. However, less is known about placental function in the abnormal metabolic and endocrine environment associated with maternal obesity during pregnancy. This review discusses the placental consequences of maternal obesity induced either naturally or experimentally by increasing maternal nutritional intake and/or changing the dietary composition. It takes a comparative, multi-species approach and focusses on placental size, morphology, nutrient transport, metabolism and endocrine function during the later stages of obese pregnancy. It also examines the interventions that have been made during pregnancy in an attempt to alleviate the more adverse impacts of maternal obesity on placental phenotype. The review highlights the potential role of adaptations in placental phenotype as a contributory factor to the pregnancy complications and changes in fetal growth and development that are associated with maternal obesity.

Maternal microbiome in preeclampsia pathophysiology and implications on offspring health

Preeclampsia is a devastating hypertensive pregnancy disorder that currently affects 2%–8% of pregnancies worldwide. It is associated with maternal and fetal mortality and morbidity and adverse health outcomes both in mom and offspring beyond pregnancy. The pathophysiology is not completely understood, and there are no approved therapies to specifically treat for the disease, with only few therapies approved to manage symptoms. Recent advances suggest that aberrations in the composition of the microbiome may play a role in the pathogenesis of various diseases including preeclampsia. The maternal and uteroplacental environments greatly influence the long‐term health outcomes of the offspring through developmental programming mechanisms. The current review summarizes recent developments on the role of the microbiome in adverse pregnancy outcomes with a focus on preeclampsia. It also discusses the potential role of the maternal microbiome in fetal programming; explores gut‐targeted therapeutics advancement and their implications in the treatment of preeclampsia.