Metabolomic profile associated with obstructive sleep apnoea severity in obese pregnant women with gestational diabetes mellitus: A pilot study

Allostatic load in early pregnancy and sleep-disordered breathing

OBJECTIVES

To assess the association between allostatic load in early pregnancy and sleep-disordered breathing (SDB) during pregnancy.

METHODS

High allostatic load in the first trimester was defined as ≥ 4 of 12 biomarkers (systolic blood pressure, diastolic blood pressure, body mass index, cholesterol, low-density lipoprotein, high-density lipoprotein, high sensitivity C-reactive protein, triglycerides, insulin, glucose, creatinine, and albumin) in the unfavorable quartile. SDB was objectively measured using the Embletta-Gold device and operationalized as "SDB ever" in early (6-15 weeks) or mid-pregnancy (22-31 weeks); SDB at each time point was analyzed as secondary outcomes. Multivariable logistic regression was used to test the association between high allostatic load and SDB, adjusted for confounders. Moderation and sensitivity analyses were conducted to assess the role of allostatic load in racial disparities of SDB and obesity affected the relationship between allostatic load and SDB.

RESULTS

High allostatic load was present in 35.0% of the nuMoM2b cohort. The prevalence of SDB ever occurred among 8.3% during pregnancy. After adjustment, allostatic load remained significantly associated with SDB ever (aOR= 5.3; 3.6-7.9), in early-pregnancy (aOR= 7.0; 3.8-12.8), and in mid-pregnancy (aOR= 5.8; 3.7-9.1). The association between allostatic load and SDB was not significantly different for people with and without obesity. After excluding BMI from the allostatic load score, the association decreased in magnitude (aOR= 2.6; 1.8-3.9).

CONCLUSION

The association between allostatic load and SDB was independent of confounders including BMI. The complex and likely bidirectional relationship between chronic stress and SDB deserves further study in reducing SDB.

PsyNBIOsis: Investigating the Association between Maternal Gestational Diabetes, Mental Health, Diet and Childhood Obesity Risk: Protocol for a Prospective, Longitudinal, Observational Study

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with poorer maternal mental health (depression and anxiety). Maternal mental health and GDM are likely to influence diet, which in turn impacts the course of GDM. Maternal diet may also be directly or indirectly associated with changes in infant anthropometry. The aims of this study are to (1) examine the associations between maternal GDM, mental health and diet, and (2) evaluate the associations between these maternal factors, breastmilk composition and infant anthropometry.

METHODS

This prospective, observational, longitudinal cohort study compares a cohort of women with and without GDM. Maternal mental health and diet are assessed using validated questionnaires. Breastmilk composition is measured with the Human Milk Analyzer, and infant body composition is measured with air displacement plethysmography.

SIGNIFICANCE AND IMPACT

Once data have been collected, PsyNBIOsis will provide evidence for the associations between maternal mental health, GDM status and diet, and their impact on breastmilk composition and early infant growth. The results may inform the Developmental Origins of Health and Disease framework and provide data on which to build cost-effective interventions to prevent both the development of mental health issues in mothers and adverse growth patterns in infants.

Sleep insufficiency, circadian rhythms, and metabolomics: the connection between metabolic and sleep disorders

PURPOSE

US adults who report experiencing insufficient sleep are more likely to suffer from metabolic disorders such as hyperlipidemia, diabetes, and obesity than those with sufficient sleep. Less is understood about the underlying molecular mechanisms connecting these phenomena. A systematic, qualitative review of metabolomics studies exploring metabolic changes in response to sleep insufficiency, sleep deprivation, or circadian disruption was conducted in accordance with PRISMA guidelines.

METHODS

An electronic literature review in the PubMed database was performed considering publications through May 2021 and screening and eligibility criteria were applied to articles retrieved. The following keywords were used: "metabolomics" and "sleep disorders" or "sleep deprivation" or "sleep disturbance" or "circadian rhythm." After screening and addition of studies included from reference lists of retrieved studies, 16 records were identified for review.

RESULTS

Consistent changes in metabolites were observed across studies between individuals experiencing sleep deprivation compared to non-sleep deprived controls. Significant increases in phosphatidylcholines, acylcarnitines, sphingolipids, and other lipids were consistent across studies. Increased levels of amino acids such as tryptophan and phenylalanine were also noted. However, studies were limited to small samples of young, healthy, mostly male participants conducted in short inpatient sessions, limiting generalizability.

CONCLUSION

Changes in lipid and amino acid metabolites accompanying sleep deprivation and/or circadian rhythms may indicate cellular membrane and protein breakdown underlying the connection between sleep disturbance, hyperlipidemia, and other metabolic disorders. Larger epidemiological studies examining changes in the human metabolome in response to chronic insufficient sleep would help elucidate this relationship.

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).

Whole Agrocybe cylindracea Prevented Obesity Linking with Modification of Gut Microbiota and Associated Fecal Metabolites in High-Fat Diet-Fed Mice

SCOPE

Whole-food-based strategies to prevent metabolic diseases are growing interests. Agrocybe cylindracea (AC) is a major edible mushroom with high values of nutrition, but little is known about its health benefits as a portion of whole food.

METHODS AND RESULTS

Diet-induced obese, C57BL/6J mice were fed an HFD with or without AC (3% or 5%, w/w in the diet) for 9 weeks. The results showed that dietary AC reduced body weight, adipose accumulation, impairment of glucose tolerance, lipid levels, and liver injury in HFD-fed mice. Moreover, AC not only prevented HFD-induced gut disorder, as indicated by the enriched probiotic Bifidobacterium and reduced endotoxin-bearing Proteobacteria, but also improved the endotoxin (LPS) level and gut tissue structure. Fecal metabolites such as harmine and harmanine were also remarkably altered by AC. Spearman's correlation analysis revealed that the AC-altered microbes and metabolites were strongly correlated with obesity-related indexes.

CONCLUSION

These findings suggest that dietary AC prevents HFD-induced obesity and its complications in association with modulating gut microbiota and associated fecal metabolites. This article is protected by copyright. All rights reserved.

Untargeted Metabolomic Profiling of Liver in a Chronic Intermittent Hypoxia Mouse Model

Obstructive sleep apnea (OSA) has been demonstrated to be associated with liver injury. Nevertheless, the mechanisms linking the two disorders remain largely unexplored to date. Based on UHPLC/Q-TOF MS platform, the present study aimed to study the hepatic metabolomic profiling in a chronic intermittent hypoxia (CIH) mouse model to identify altered metabolites and related metabolic pathways. C57BL/6 Mice (n = 12 each group) were exposed to intermittent hypoxia or control conditions (room air) for 12 weeks. At the end of the exposure, liver enzymes and histological changes were assessed. Untargeted metabolomics approach by UHPLC/Q-TOF MS and orthogonal partial least squares-discriminant analysis (OPLS-DA) were applied to screen altered metabolites in mice liver. Bioinformatics analyses were applied to identify the related metabolic pathways. CIH treatment caused a remarkable liver injury in mice. A total of 27 differential metabolites in negative ion mode and 44 in positive ion mode were identified between the two groups. These metabolites were correlated to multiple biological and metabolic processes, including various amino acid metabolism, membrane transport, lipid metabolism, carbohydrate metabolism, nucleotide metabolism, ferroptosis, etc. three differential metabolites including glutathione, glutathione disulfide, arachidonic acid (peroxide free) were identified in the ferroptosis pathway. CIH was associated with a significant metabolic profiling change in mice liver. The metabolites in amino acid metabolism, membrane transport, lipid metabolism, carbohydrate metabolism, nucleotide metabolism, and ferroptosis played an important role in CIH-induced liver injury. These findings contribute to a better understanding of the mechanisms linking OSA and liver injury and help identify potential therapeutic targets.