Microbial transmission from mothers with obesity or diabetes to infants: an innovative opportunity to interrupt a vicious cycle.

Maternal obesity and diabetes dramatically increase the long-term risk for obesity in the next generation, and pregnancy and lactation may be critical periods at which to aim primary prevention to break the obesity cycle. It is becoming increasingly clear that the gut microbiome in newborns and infants plays a significant role in gut health and therefore child development. Alteration of the early infant gut microbiome has been correlated with the development of childhood obesity and autoimmune conditions, including asthma, allergies and, more recently, type 1 diabetes. This is likely to be due to complex interactions between mode of delivery, antibiotic use, maternal diet, components of breastfeeding and a network of regulatory events involving both the innate and adaptive immune systems within the infant host. Each of these factors are critical for informing microbiome development and can affect immune signalling, toxin release and metabolic signals, including short-chain fatty acids and bile acids, that regulate appetite, metabolism and inflammation. In several randomised controlled trials, probiotics have been administered with the aim of targeting the microbiome during pregnancy to improve maternal and infant health but the findings have often been confounded by mode of delivery, antibiotic use, ethnicity, infant sex, maternal health and length of exposure. Understanding how nutritional exposure, including breast milk, affects the assembly and development of both maternal and infant microbial communities may help to identify targeted interventions during pregnancy and in infants born to mothers with obesity or diabetes to slow the transmission of obesity risk to the next generation. The aim of this review is to discuss influences on infant microbiota colonisation and the mechanism(s) underlying how alterations due to maternal obesity and diabetes may lead to increased risk of childhood obesity.

Maternal diet alters long-term innate immune cell memory in fetal and juvenile hematopoietic stem and progenitor cells in nonhuman primate offspring.

Maternal overnutrition increases inflammatory and metabolic disease risk in postnatal offspring. This constitutes a major public health concern due to increasing prevalence of these diseases, yet mechanisms remain unclear. Here, using nonhuman primate models, we show that maternal Western-style diet (mWSD) exposure is associated with persistent pro-inflammatory phenotypes at the transcriptional, metabolic, and functional levels in bone marrow-derived macrophages (BMDMs) from 3-year-old juvenile offspring and in hematopoietic stem and progenitor cells (HSPCs) from fetal and juvenile bone marrow and fetal liver. mWSD exposure is also associated with increased oleic acid in fetal and juvenile bone marrow and fetal liver. Assay for transposase-accessible chromatin with sequencing (ATAC-seq) profiling of HSPCs and BMDMs from mWSD-exposed juveniles supports a model in which HSPCs transmit pro-inflammatory memory to myeloid cells beginning in utero. These findings show that maternal diet alters long-term immune cell developmental programming in HSPCs with proposed consequences for chronic diseases featuring altered immune/inflammatory activation across the lifespan.

Parental Vaccine Hesitancy and Risk of Pediatric Influenza Under-Vaccination in a Safety-Net Health Care System.

OBJECTIVE: To measure the risk of influenza under-vaccination in children of vaccine-hesitant parents, referent to children of nonhesitant parents, in a sample of disadvantaged families in one influenza season. STUDY DESIGN: A prospective observational cohort study of English- and Spanish-speaking parents of 2-year-olds presenting at random for well, sick, or specialty visit care from August 1, 2019 to February 28, 2020. Parents answered demographic questions and the Parent Attitudes about Childhood Vaccines survey. We followed children until season's end, extracting vaccination data on April 30, 2020. We dichotomized vaccination status as unvaccinated or partially/fully vaccinated, analyzing data with multivariable Poisson regression; in secondary analyses, we conducted adjusted time-to-event analyses. RESULTS: Overall, 263 parents consented (response rate: 90%); our final sample included 255 dyads. Thirty-three (13%) parents were vaccine hesitant. In adjusted analyses, children of hesitant parents (n = 33) had a 195% increased risk (adjusted Risk Ratio 2.95; 95% confidence interval 1.91, 4.56) of being unvaccinated at season's end, referent to children of nonhesitant parents (n = 222). In time-to-event analyses, children of vaccine-hesitant parents were also more likely to be unvaccinated before influenza activity peaked (P = .02). CONCLUSIONS: Parental vaccine hesitancy tripled the risk of pediatric influenza nonvaccination in a sample of poor and minority families during the 2019 to 2020 influenza season. As parental vaccine hesitancy appears to exacerbate pediatric influenza vaccination disparities, future work should explore parental hesitancy with poor and minority stakeholders and tailor evidence-based interventions to benefit children from these communities who receive care at all practice sites.

Gestational Diabetes Is Uniquely Associated With Altered Early Seeding of the Infant Gut Microbiota.

Gestational diabetes mellitus (GDM) is a worldwide public health problem affecting up to 27% of pregnancies with high predictive values for childhood obesity and inflammatory diseases. Compromised seeding of the infant gut microbiota is a risk factor for immunologic and metabolic diseases in the offspring; however, how GDM along with maternal obesity interact to alter colonization remains unknown. We hypothesized that GDM individually and in combination with maternal overweight/obesity would alter gut microbial composition, diversity, and short-chain fatty acid (SCFA) levels in neonates. We investigated 46 full-term neonates born to normal-weight or overweight/obese mothers with and without GDM, accounting for confounders including cesarean delivery, lack of breastfeeding, and exposure to antibiotics. Gut microbiota in 2-week-old neonates born to mothers with GDM exhibited differences in abundance of 26 microbial taxa; 14 of which showed persistent differential abundance after adjusting for pre-pregnancy BMI. Key pioneering gut taxa, including potentially important taxa for establishing neonatal immunity, were reduced. Lactobacillus, Flavonifractor, Erysipelotrichaceae, and unspecified families in Gammaproteobacteria were significantly reduced in neonates from mothers with GDM. GDM was associated with an increase in microbes involved in suppressing early immune cell function (Phascolarctobacterium). No differences in infant stool SCFA levels by maternal phenotype were noted; however, significant correlations were found between microbial abundances and SCFA levels in neonates. Our results suggest that GDM alone and together with maternal overweight/obesity uniquely influences seeding of specific infant microbiota in patterns that set the stage for future risk of inflammatory and metabolic disease.

Reproductive Health Care in Catholic Facilities: A Scoping Review.

OBJECTIVE: Given the rise in Catholic ownership of U.S. health care facilities, we aimed to examine reproductive health care provision and patient outcomes. We performed a scoping review, which maps the literature and considers inclusion of studies that are not specifically quantitative. DATA SOURCES: We searched five databases (MEDLINE, EMBASE, Web of Science and Cochrane Library, ClinialTrials.gov) from inception through August 2018 using terms related to reproductive health care and religion. METHODS OF STUDY SELECTION: We screened 2,906 studies. Articles were included if in English, included primary research data, and referenced U.S.-based Catholic facilities. We reviewed the reference lists of included articles. We excluded articles that addressed the relationship of patient or health care provider religion to provision of reproductive services, described reproductive health care services in non-Catholic facilities, or reported legal cases or concerns. Two independent reviewers screened all citations, a third reviewer resolved differences, and all three reviewers categorized included citations. TABULATION, INTEGRATION, AND RESULTS: We included 27 studies. Investigators most commonly focused on the provision of emergency contraception (n=9) or other contraceptive and sterilization methods (n=7); few focused on a range of family planning methods (n=3), natural family planning (n=2), ectopic pregnancy management (n=2), abortion care (n=2), miscarriage management (n=1), and infertility care (n=1). The most common study designs were cross-sectional (18/27 [67%]) and qualitative investigations (6/27 [22%]). Common data collection approaches included surveys, interviews, and mystery caller designs. Two studies involved authors with Catholic hospital affiliations and one of these reported patient outcomes; no other patient outcome reports were found. Studies cited restrictions to care in comparison with non-Catholic settings and multisite studies demonstrated variable rates of provision of reproductive health services across Catholic sites. CONCLUSIONS: Despite the significant proportion and recent growth of Catholic health care within the U.S. health care sector, little is known about reproductive health outcomes in these settings and in comparison with other settings.

Author Correction: The gut microbiota in infants of obese mothers increases inflammation and susceptibility to NAFLD.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Imbalance in gut microbes from babies born to obese mothers increases gut permeability and myeloid cell adaptations that provoke obesity and NAFLD.

Non-alcoholic fatty liver disease (NAFLD) is a multifactorial disease affecting nearly 40% of obese youth and up to 10% of the general pediatric population. A key aspect of NAFLD pathogenesis is proinflammatory hepatic macrophage activation and hepatic recruitment of circulating monocytes, which originate from the bone marrow. In neonates, the activation and polarization of myeloid immune cells are normally shaped in part by systemic factors derived from intestinal microbiota during the first 1000 days of life. Perturbations of the gut microbiome, and in turn the metabolites and bacterial products released systemically, can affect the functional phenotype of these immune cells. Evidence in germ-free mice has shown that fecal microbial transfer from obese mice or obese human donors promotes obesity and inflammation in the recipients, suggesting a direct role for the gut microbiome in promoting obesity and possibly NAFLD. Indeed, patients suffering from NAFLD show evidence for dysbiosis, increased gut permeability, and changes in bile acids that drive the progression of hepatic inflammation toward non-alcoholic steatohepatitis (NASH), the more severe form of the disease. Compared with infants born to normal-weight mothers, we previously showed that the gut microbiome from neonates born to obese mothers is compositionally distinct. However, whether this alteration in early gut microbiota in infants born to obese mothers can cause inflammatory processes that initiate development of NAFLD or obesity is unknown. How these alterations contribute to long-term immune cell mediated liver inflammation and progression of NAFLD needs to be determined. Our recently published work (Soderborg et al., Nat Commun 9:4462) demonstrates a causative role of early life microbiome dysbiosis in infants born to mothers with obesity in novel pathways that promote developmental programming of NAFLD.

Low Neonatal Plasma n-6/n-3 PUFA Ratios Regulate Offspring Adipogenic Potential and Condition Adult Obesity Resistance.

Adipose tissue expansion progresses rapidly during postnatal life, influenced by both prenatal maternal factors and postnatal developmental cues. The ratio of omega-6 (n-6) relative to n-3 polyunsaturated fatty acids (PUFAs) is believed to regulate perinatal adipogenesis, but the cellular mechanisms and long-term effects are not well understood. We lowered the fetal and postnatal n-6/n-3 PUFA ratio exposure in wild-type offspring under standard maternal dietary fat amounts to test the effects of low n-6/n-3 ratios on offspring adipogenesis and adipogenic potential. Relative to wild-type pups receiving high perinatal n-6/n-3 ratios, subcutaneous adipose tissue in 14-day-old wild-type pups receiving low n-6/n-3 ratios had more adipocytes that were smaller in size; decreased Pparγ2, Fabp4, and Plin1; several lipid metabolism mRNAs; coincident hypermethylation of the PPARγ2 proximal promoter; and elevated circulating adiponectin. As adults, offspring that received low perinatal n-6/n-3 ratios were diet-induced obesity (DIO) resistant and had a lower positive energy balance and energy intake, greater lipid fuel preference and non-resting energy expenditure, one-half the body fat, and better glucose clearance. Together, the findings support a model in which low early-life n-6/n-3 ratios remodel adipose morphology to increase circulating adiponectin, resulting in a persistent adult phenotype with improved metabolic flexibility that prevents DIO.

The gut microbiota in infants of obese mothers increases inflammation and susceptibility to NAFLD.

Maternal obesity is associated with increased risk for offspring obesity and non-alcoholic fatty liver disease (NAFLD), but the causal drivers of this association are unclear. Early colonization of the infant gut by microbes plays a critical role in establishing immunity and metabolic function. Here, we compare germ-free mice colonized with stool microbes (MB) from 2-week-old infants born to obese (Inf-ObMB) or normal-weight (Inf-NWMB) mothers. Inf-ObMB-colonized mice demonstrate increased hepatic gene expression for endoplasmic reticulum stress and innate immunity together with histological signs of periportal inflammation, a histological pattern more commonly reported in pediatric cases of NAFLD. Inf-ObMB mice show increased intestinal permeability, reduced macrophage phagocytosis, and dampened cytokine production suggestive of impaired macrophage function. Furthermore, exposure to a Western-style diet in Inf-ObMB mice promotes excess weight gain and accelerates NAFLD. Overall, these results provide functional evidence supporting a causative role of maternal obesity-associated infant dysbiosis in childhood obesity and NAFLD.

Pyrroloquinoline quinone prevents developmental programming of microbial dysbiosis and macrophage polarization to attenuate liver fibrosis in offspring of obese mice.

Increasingly, evidence suggests that exposure to maternal obesity creates an inflammatory environment in utero, exerting long-lasting postnatal signatures on the juvenile innate immune system and microbiome that may predispose offspring to development of fatty liver disease. We found that exposure to a maternal Western-style diet (WD) accelerated fibrogenesis in the liver of offspring and was associated with early recruitment of proinflammatory macrophages at 8-12 weeks and microbial dysbiosis as early as 3 weeks of age. We further demonstrated that bone marrow-derived macrophages (BMDMs) were polarized toward an inflammatory state at 8 weeks of age and that a potent antioxidant, pyrroloquinoline quinone (PQQ), reversed BMDM metabolic reprogramming from glycolytic toward oxidative metabolism by restoring trichloroacetic acid cycle function at isocitrate dehydrogenase. This resulted in reduced inflammation and inhibited collagen fibril formation in the liver at 20 weeks of age, even when PQQ was withdrawn at 3 weeks of age. Beginning at 3 weeks of age, WD-fed mice developed a decreased abundance of Parabacteroides and Lactobacillus, together with increased Ruminococcus and decreased tight junction gene expression by 20 weeks, whereas microbiota of mice exposed to PQQ retained compositional stability with age, which was associated with improved liver health. Conclusion: Exposure to a maternal WD induces early gut dysbiosis and disrupts intestinal tight junctions, resulting in BMDM polarization and induction of proinflammatory and profibrotic programs in the offspring that persist into adulthood. Disrupted macrophage and microbiota function can be attenuated by short-term maternal treatment with PQQ prior to weaning, suggesting that reshaping the early gut microbiota in combination with reprogramming macrophages during early weaning may alleviate the sustained proinflammatory environment, preventing the rapid progression of nonalcoholic fatty liver disease to nonalcoholic steatohepatitis in offspring of obese mothers. (Hepatology Communications 2018;2:313-328).

Alterations in human milk leptin and insulin are associated with early changes in the infant intestinal microbiome.

BACKGROUND: Increased maternal body mass index (BMI) is a robust risk factor for later pediatric obesity. Accumulating evidence suggests that human milk (HM) may attenuate the transfer of obesity from mother to offspring, potentially through its effects on early development of the infant microbiome. OBJECTIVES: Our objective was to identify early differences in intestinal microbiota in a cohort of breastfeeding infants born to obese compared with normal-weight (NW) mothers. We also investigated relations between HM hormones (leptin and insulin) and both the taxonomic and functional potentials of the infant microbiome. DESIGN: Clinical data and infant stool and fasting HM samples were collected from 18 NW [prepregnancy BMI (in kg/m(2)) <24.0] and 12 obese (prepregnancy BMI >30.0) mothers and their exclusively breastfed infants at 2 wk postpartum. Infant body composition at 2 wk was determined by air-displacement plethysmography. Infant gastrointestinal microbes were estimated by using 16S amplicon and whole-genome sequencing. HM insulin and leptin were determined by ELISA; short-chain fatty acids (SCFAs) were measured in stool samples by using gas chromatography. Power was set at 80%. RESULTS: Infants born to obese mothers were exposed to 2-fold higher HM insulin and leptin concentrations (P < 0.01) and showed a significant reduction in the early pioneering bacteria Gammaproteobacteria (P = 0.03) and exhibited a trend for elevated total SCFA content (P < 0.06). Independent of maternal prepregnancy BMI, HM insulin was positively associated with both microbial taxonomic diversity (P = 0.03) and Gammaproteobacteria (e.g., Enterobacteriaceae; P = 0.04) and was negatively associated with Lactobacillales (e.g., Streptococcaceae; P = 0.05). Metagenomic analysis showed that HM leptin and insulin were associated with decreased bacterial proteases, which are implicated in intestinal permeability, and reduced concentrations of pyruvate kinase, a biomarker of pediatric gastrointestinal inflammation. CONCLUSION: Our results indicate that, although maternal obesity may adversely affect the early infant intestinal microbiome, HM insulin and leptin are independently associated with beneficial microbial metabolic pathways predicted to increase intestinal barrier function and reduce intestinal inflammation. This trial was registered at clinicaltrials.gov as NCT01693406.