ABSTRACT
Pregnancy alters many physiological systems, including the maternal gut microbiota. Diet is a key regulator of this system and can alter the host immune system to promote inflammation. Multiple perinatal disorders have been associated with inflammation, maternal metabolic alterations, and gut microbial dysbiosis, including gestational diabetes mellitus, pre-eclampsia, preterm birth, and mood disorders. However, the effects of high-inflammatory diets on the gut microbiota during pregnancy have yet to be fully explored. We aimed to address this gap using a system-based approach to characterize associations among dietary inflammatory potential, a measure of diet quality, and the gut microbiome during pregnancy. Forty-seven pregnant persons were recruited prior to 16 weeks of gestation. Participants completed a food frequency questionnaire (FFQ) and provided fecal samples. Dietary inflammatory potential was assessed using the Dietary Inflammatory Index (DII) from the FFQ data. Fecal samples were analyzed using 16S rRNA amplicon sequencing. Differential taxon abundances with respect to the DII score were identified, and the microbial metabolic potential was predicted using PICRUSt2. Inflammatory diets were associated with decreased vitamin and mineral intake and a dysbiotic gut microbiota structure and predicted metabolism. Gut microbial compositional differences revealed a decrease in short-chain fatty acid producers such as Faecalibacterium, and an increase in predicted vitamin B12 synthesis, methylglyoxal detoxification, galactose metabolism, and multidrug efflux systems in pregnant individuals with increased DII scores. Dietary inflammatory potential was associated with a reduction in the consumption of vitamins and minerals and predicted gut microbiota metabolic dysregulation.
Subject(s)
Avitaminosis , Gastrointestinal Microbiome , Premature Birth , Infant, Newborn , Female , Pregnancy , Humans , Dysbiosis , RNA, Ribosomal, 16S , Diet , Vitamins , InflammationABSTRACT
Early-onset colorectal cancer (EOCRC) is defined as a diagnosis of colorectal cancer (CRC) in individuals younger than 50 years of age. While overall CRC rates in the United States (US) decreased between 2001 and 2018, EOCRC rates have increased. This research project aims to evaluate the feasibility and acceptability of Time-Restricted Eating (TRE), Mindfulness, or TRE combined with Mindfulness among young to middle-aged adults at risk of EOCRC. Forty-eight participants will be randomly assigned to one of four groups: TRE, Mindfulness, TRE and Mindfulness, or Control. Data on feasibility, adherence, and acceptability will be collected. Measures assessed at baseline and post-intervention will include body weight, body composition, dietary intake, physical activity, sleep behavior, circulating biomarkers, hair cortisol, and the gut microbiome. The effects of the intervention on the following will be examined: (1) acceptability and feasibility; (2) body weight, body composition, and adherence to TRE; (3) circulating metabolic, inflammation, and oxidative stress biomarkers; (4) intestinal inflammation; and (5) the gut microbiome. TRE, combined with Mindfulness, holds promise for stress reduction and weight management among individuals at risk of EOCRC. The results of this pilot study will inform the design and development of larger trials aimed at preventing risk factors associated with EOCRC.
Subject(s)
Colorectal Neoplasms , Mindfulness , Middle Aged , Humans , Young Adult , Mindfulness/methods , Pilot Projects , Risk Factors , Body Weight , Colorectal Neoplasms/prevention & control , Inflammation , BiomarkersABSTRACT
Background: Pregnancy alters many physiological systems, including the maternal gut microbiota. Diet is a key regulator of this system and can alter the host immune system to promote inflammation. Multiple perinatal disorders have been associated with inflammation, maternal metabolic alterations, and gut microbial dysbiosis, including gestational diabetes mellitus, preeclampsia, preterm birth, and mood disorders. However, the effects of high inflammatory diets on the gut microbiota during pregnancy have yet to be fully explored. Objective: To use a systems-based approach to characterize associations among dietary inflammatory potential, a measure of diet quality, and the gut microbiome during pregnancy. Methods: Forty-nine pregnant persons were recruited prior to 16 weeks of gestation. Participants completed a food frequency questionnaire (FFQ) and provided fecal samples. Dietary inflammatory potential was assessed using the Dietary Inflammatory Index (DII) from FFQ data. Fecal samples were analyzed using 16S rRNA amplicon sequencing. Differential taxon abundance with respect to DII score were identified, and microbial metabolic potential was predicted using PICRUSt2. Results: Inflammatory diets were associated with decreased vitamin and mineral intake and dysbiotic gut microbiota structure and predicted metabolism. Gut microbial compositional differences revealed a decrease in short chain fatty acid producers such as Faecalibacterium, and an increase in predicted vitamin B12 synthesis, methylglyoxal detoxification, galactose metabolism and multi drug efflux systems in pregnant individuals with increased DII scores. Conclusions: Dietary inflammatory potential was associated with a reduction in the consumption of vitamins & minerals and predicted gut microbiota metabolic dysregulation.
ABSTRACT
Perinatal perceived stress can contribute to worse health outcomes for the parent-child dyad. Given the emerging relationship between the microbiota-gut-brain axis and stress, this study sought to elucidate connections between bowel symptoms and the gut microbiome in relation to perceived stress at three time points in the perinatal period: two during pregnancy and one postpartum. Ninety-five pregnant individuals participated in a prospective cohort study from April 2017 to November 2019. Researchers assessed Perceived Stress Scale-10 (PSS); bowel symptoms (according to the IBS Questionnaire); psychiatrist assessment of new onset or exacerbated depression and anxiety; and fecal samples analyzed for alpha diversity (measures of gut microbiome diversity utilizing Shannon, Observed OTUs, and Faith's PD) at each timepoint. Covariates included weeks of gestation and weeks postpartum. PSS scores were divided into "Perceived Self-Efficacy" and "Perceived Helplessness." Increased gut microbial diversity was associated with decreased bowel symptoms, decreased overall perceived stress, increased ability to cope with adversity, and decreased distress in the postpartum period. This study found a significant association between a less diverse microbial community, lower self-efficacy early in pregnancy, and greater bowel symptoms and perceived helplessness later in the perinatal period, relationships that may ultimately point to novel diagnostic methods and interventions for perceived stress based on the microbiota-gut-brain axis.
Subject(s)
Gastrointestinal Microbiome , Microbiota , Pregnancy , Female , Humans , Brain-Gut Axis , Prospective Studies , Stress, PsychologicalABSTRACT
Those with mild cognitive impairment (MCI), a precursor to dementia, have a gut microbiome distinct from healthy individuals, but this has only been shown in healthy individuals, not in those exhibiting several risk factors for dementia. Using amplicon 16S rRNA gene sequencing in a case-control study of 60 older (ages 55-76), obese, predominately female, African American adults, those with MCI (cases) had different gut microbiota profiles than controls. While microbial community diversity was similar between cases and controls, the abundances of specific microbial taxa weren't, such as Parabacteroides distasonis (lower in cases) and Dialister invisus (higher in cases). These differences disappeared after adjusting for markers of oxidative stress and systemic inflammation. Cognitive scores were positively correlated with levels of Akkermansia muciniphila, a bacterium associated with reduced inflammation. Our study shows that gut microbial composition may be associated with inflammation, oxidative stress, and MCI in those at high risk for dementia.
Subject(s)
Cognitive Dysfunction , Gastrointestinal Microbiome , Obesity , Aged , Female , Humans , Middle Aged , Black or African American , Case-Control Studies , Cognitive Dysfunction/microbiology , Dementia , Gastrointestinal Microbiome/genetics , Inflammation , Obesity/microbiology , RNA, Ribosomal, 16S/genetics , MaleABSTRACT
Although we have effective treatments for depression and anxiety, we lack mechanistic understanding or evidence-based strategies to tailor these treatments in the context of major comorbidities such as obesity. The current feasibility study uses functional neuroimaging and biospecimen data to determine if changes in inflammatory markers, fecal short-chain fatty acids, and neural circuit-based targets can predict depression and anxiety outcomes among participants with comorbid obesity. Blood and stool samples and functional magnetic resonance imaging data were obtained at baseline and 2 months, during the parent ENGAGE-2 trial. From 30 participants with both biospecimen and fMRI data, this subsample study explored the relationship among changes in inflammatory markers and fecal short-chain fatty acids and changes in neural targets, and their joint relationship with depression and anxiety symptoms. Bivariate and partial correlation, canonical correlation, and partial least squares analyses were conducted, with adjustments for age, sex, and treatment group. Initial correlation analyses revealed three inflammatory markers (IL-1RA, IL-6, and TNF-α) and five neural targets (in Negative Affect, Positive Affect, and Default Mode Circuits) with significantly associated changes at 2 months. Partial least squares analyses then showed that changes in IL-1RA and TNF-α and changes in three neural targets (in Negative Affect and Positive Affect Circuits) at 2 months were associated with changes in depression and anxiety symptoms at 6 months. This study sheds light on the plausibility of incorporation of inflammatory and gastrointestinal biomarkers with neural targets as predictors of depression and comorbid anxiety outcomes among patients with obesity.
Subject(s)
Depression , Interleukin 1 Receptor Antagonist Protein , Humans , Tumor Necrosis Factor-alpha , Anxiety , ObesityABSTRACT
BACKGROUND: The microbiome-gut-brain-axis (MGBA) is emerging as an important mechanistic link between diet and mental health. The role of significant modifiers of the MGBA, including gut microbial metabolites and systemic inflammation, in individuals comorbid with obesity and mental disorders, is under-investigated. OBJECTIVES: This exploratory analysis examined associations among microbial metabolites-fecal SCFAs, plasma inflammatory cytokines, and diet with depression and anxiety scores in adults comorbid with obesity and depression. METHODS: Stool and blood were obtained from a subsample (n = 34) of participants enrolled in an integrated behavioral intervention for weight loss and depression. Pearson partial correlation and multivariate analyses determined associations among changes in fecal SCFAs (propionic, butyric, acetic, and isovaleric acids), plasma cytokines [C-reactive protein, interleukin 1 beta, interleukin 1 receptor antagonist (IL-1RA), interleukin 6, and TNF-α], and 35 dietary markers over 2 mo, and changes in SCL-20 (Depression Symptom Checklist 20-item) and GAD-7 (Generalized Anxiety Disorder 7-Item) scores over 6 mo. RESULTS: Changes in the SCFAs and TNF-α at 2 mo were positively associated (standardized coefficients: 0.06-0.40; 0.03-0.34) with changes in depression and anxiety scores at 6 mo, whereas changes in IL-1RA at 2 mo were inversely associated (standardized coefficients: -0.24; -0.05). After 2 mo, changes in 12 dietary markers, including animal protein, were associated with changes in SCFAs, TNF-α, or IL-1RA at 2 mo (standardized coefficients: -0.27 to 0.20). Changes in 11 dietary markers, including animal protein, at 2 mo were associated with changes in depression or anxiety symptom scores at 6 mo (standardized coefficients: -0.24 to 0.20; -0.16 to 0.15). CONCLUSIONS: Gut microbial metabolites and systemic inflammation may be biomarkers of importance within the MGBA, linking dietary markers, such as animal protein intake, to depression and anxiety for individuals with comorbid obesity. These findings are exploratory and warrant replication.
Subject(s)
Cytokines , Tumor Necrosis Factor-alpha , Animals , Humans , Interleukin 1 Receptor Antagonist Protein , Depression , Pilot Projects , Fatty Acids, Volatile/analysis , Diet , Obesity , Inflammation/metabolism , Anxiety , Anxiety DisordersABSTRACT
Higher stress during pregnancy associates with negative outcomes and elevated inflammation. The gut microbiota, reflecting environment and social interactions, alongside host immune responses have the potential to better understand perceived stress and identify when stress is excessive in pregnancy. Two U.S. cohorts of 84 pregnant individuals, composed of urban women of color and suburban white women, completed the Perceived Stress Scale-10 (PSS-10) and provided fecal and blood samples at two time points. Confirmatory Factor Analysis assessed the robustness of a two-factor PSS-10 model (Emotional Distress/ED and Self-Efficacy/SE). Gut microbiota composition was measured by 16 S rRNA amplicon sequencing and the immune system activity was assessed with a panel of 21 T-cell related cytokines and chemokines. ED levels were higher in the suburban compared to the urban cohort, but levels of SE were similar. ED and SE levels were associated with distinct taxonomical signatures and the gut microbiota data improved the prediction of SE levels compared with models based on socio-demographic characteristics alone. Integration of self-reported symptoms, microbial and immune information revealed a possible mediation effect of Bacteroides uniformis between the immune system (through CXCL11) and SE. The study identified links between distinct taxonomical and immunological signatures with perceived stress. The data are congruent with a model where gut microbiome and immune factors, both impacting and reflecting factors such as close social relationships and dietary fiber, may modulate neural plasticity resulting in increased SE during pregnancy. The predictive value of these peripheral markers merit further study.
Subject(s)
Gastrointestinal Microbiome , Pregnancy , Humans , Female , Gastrointestinal Microbiome/physiology , Cytokines , Feces , Inflammation , Stress, PsychologicalABSTRACT
Obesity is considered an independent risk factor for colorectal cancer (CRC). Altered nutrient metabolism, particularly changes to digestion and intestinal absorption, may play an important role in the development of CRC. Iron can promote the formation of tissue-damaging and immune-modulating reactive oxygen species. We conducted a crossover, controlled feeding study to examine the effect of three, 3-week diets varying in iron and saturated fat content on the colonic milieu and systemic markers among older females with obesity. Anthropometrics, fasting venous blood and stool were collected before and after each diet. There was a minimum 3-week washout period between diets. Eighteen participants consumed the three diets (72% Black; mean age 60.4 years; mean body mass index 35.7 kg/m2). Results showed no effect of the diets on intestinal inflammation (fecal calprotectin) or circulating iron, inflammation, and metabolic markers. Pairwise comparisons revealed less community diversity between samples (beta diversity, calculated from 16S rRNA amplicon sequences) among participants when consuming a diet low in iron and high in saturated fat vs. when consuming a diet high in iron and saturated fat. More studies are needed to investigate if dietary iron represents a salient target for CRC prevention among individuals with obesity.
Subject(s)
Diet , Gastrointestinal Microbiome , Intestines , Female , Humans , Middle Aged , Diet, High-Fat/adverse effects , Fatty Acids , Inflammation/etiology , Iron , Obesity/complications , Obesity/epidemiology , Obesity/microbiology , RNA, Ribosomal, 16S/genetics , Intestines/microbiology , Intestines/physiologyABSTRACT
BACKGROUND: Compared with traditional screening questionnaires, computerised adaptive tests for severity of depression (CAT-DI) and computerised adaptive diagnostic modules for depression (CAD-MDD) show improved precision in screening for major depressive disorder. CAT measures have been tailored to perinatal women but have not been studied in low-income women of colour despite high rates of perinatal depression (PND). OBJECTIVE: This study aimed to examine the concordance between CAT and traditional measures of depression in a sample of primarily low-income black and Latina women. METHODS: In total, 373 women (49% black; 29% Latina) completed the Patient Health Questionnaire-9 (PHQ-9), CAD-MDD and CAT-DI at 845 visits across pregnancy and postpartum. We examined the concordance between continuous CAT-DI and PHQ-9 scores and between binary measures of PND diagnosis on CAD-MDD and the PHQ-9 (cut-off score >10). We examined cases with a positive PND diagnosis on the CAD-MDD but not on the PHQ-9 ('missed' cases) to determine whether clinic notes were consistent with CAD-MDD results. FINDINGS: CAT-DI and PHQ-9 scores were significantly associated (concordance correlation coefficient=0.67; 95% CI 0.58 to 0.74). CAD-MDD detected 5% more case of PND compared with PHQ-9 (p<0.001). The average per-visit rate of PND was 14.4% (14.5% in blacks, 14.9% in Latinas) on the CAD-MDD, and 9.5% (9.8% in blacks, 8.8% in Latinas) on the PHQ-9. Clinical notes were available on 60% of 'missed' cases and validated CAD-MDD PND diagnosis in 89% of cases. CONCLUSIONS: CAD-MDD detected 5% more cases of PND in women of colour compared with traditional tests, and the majority of these cases were verified by clinician notes. CLINICAL IMPLICATIONS: Use of CAT in routine clinic care may address health disparities in PND screening.
Subject(s)
Depressive Disorder, Major , Depression , Female , Humans , Mass Screening , Pregnancy , Psychiatric Status Rating Scales , Skin PigmentationABSTRACT
The cecum is a unique region in the mammalian intestinal tract in which the microbiome is localized to two compartments, the lumen and the crypts. The microbiome within crypts is particularly important as it is in direct contact with lining epithelial cells including stem cells. Here, we analyzed the microbiome in cecum of mice using multiple techniques including metagenomics. The lumen microbiome comprised Firmicutes and Bacteroidetes whereas the crypts were dominated by Proteobacteria and Deferribacteres, and the mucus comprised a mixture of these 4 phyla. The lumen microbial functional potential comprised mainly carbon metabolism, while the crypt microbiome was enriched for genes encoding stress resistance. In order to determine how this structure, assembly, and function are altered under provocative conditions, we exposed mice to overnight starvation (S), antibiotics (A), and a major surgical injury (partial hepatectomy [H]), as occurs with major surgery in humans. We have previously demonstrated that the combined effect of this "SAH" treatment leads to a major disturbance of the cecal microbiota at the bottom of crypts in a manner that disrupts crypt cell homeostasis. Here, we applied the SAH conditions and observed a loss of compartmentalization in both composition and function of the cecal microbiome associated with major shifts in local physicochemical cues including decrease of hypoxia, increase of pH, and loss of butyrate production. Taken together, these studies demonstrated a defined order, structure, and function of the cecal microbiome that can be disrupted under provocative conditions such as major surgery and its attendant exposures.IMPORTANCE The proximal colon and cecum are two intestinal regions in which the microbiome localizes to two spatially distinct compartments, the lumen and crypts. The differences in composition and function of luminal and crypt microbiome in the cecum and the effect of physiological stress on their compartmentalization remain poorly characterized. Here, we characterized the composition and function of the lumen-, mucus-, and crypt-associated microbiome in the cecum of mice. We observed a highly ordered microbial architecture within the cecum whose assembly and function become markedly disrupted when provoked by physiological stress such as surgery and its attendant preoperative treatments (i.e., overnight fasting and antibiotics). Major shifts in local physicochemical cues including a decrease in hypoxia levels, an increase in pH, and a loss of butyrate production were associated with the loss of compositional and functional compartmentalization of the cecal microbiome.
ABSTRACT
Perinatal depression is the most common complication of pregnancy and affects the mother, fetus, and infant. Recent preclinical studies and a limited number of clinical studies have suggested an influence of the gut microbiome on the onset and course of mental health disorders. In this review, we examine the current state of knowledge regarding genetics, epigenetics, heritability, and neuro-immuno-endocrine systems biology in perinatal mood disorders, with a particular focus on the interaction between these factors and the gut microbiome, which is mediated via the gut-brain axis. We also provide an overview of experimental and analytical methods that are currently available to researchers interested in elucidating the influence of the gut microbiome on mental health disorders during pregnancy and postpartum.
Subject(s)
Depressive Disorder, Major/therapy , Gastrointestinal Microbiome/physiology , Precision Medicine/methods , Pregnancy Complications/therapy , Brain/metabolism , Depressive Disorder, Major/metabolism , Depressive Disorder, Major/psychology , Female , Humans , Infant , Microbiota/physiology , Postpartum Period/metabolism , Postpartum Period/psychology , Precision Medicine/psychology , Pregnancy , Pregnancy Complications/metabolism , Pregnancy Complications/psychologyABSTRACT
BACKGROUND: The maturation of the female germ cell, the oocyte, requires the synthesis and storing of all the necessary metabolites to support multiple divisions after fertilization. Oocyte maturation is only possible in the presence of surrounding, diverse, and changing layers of somatic cells. Our understanding of metabolic interactions between the oocyte and somatic cells has been limited due to dynamic nature of ovarian follicle development, thus warranting a systems approach. RESULTS: Here, we developed a genome-scale metabolic model of the mouse ovarian follicle. This model was constructed using an updated mouse general metabolic model (Mouse Recon 2) and contains several key ovarian follicle development metabolic pathways. We used this model to characterize the changes in the metabolism of each follicular cell type (i.e., oocyte, granulosa cells, including cumulus and mural cells), during ovarian follicle development in vivo. Using this model, we predicted major metabolic pathways that are differentially active across multiple follicle stages. We identified a set of possible secreted and consumed metabolites that could potentially serve as biomarkers for monitoring follicle development, as well as metabolites for addition to in vitro culture media that support the growth and maturation of primordial follicles. CONCLUSIONS: Our systems approach to model follicle metabolism can guide future experimental studies to validate the model results and improve oocyte maturation approaches and support growth of primordial follicles in vitro.
Subject(s)
Cell Communication , Genome , Models, Biological , Ovarian Follicle/metabolism , Animals , Cell Differentiation , Female , Metabolic Networks and Pathways , Mice , Ovarian Follicle/cytologyABSTRACT
Dynamic systems biology aims to identify the molecular mechanisms governing cell fate decisions through the analysis of living cells. Large scale molecular information from living cells can be obtained from reporter constructs that provide activities for either individual transcription factors or multiple factors binding to the full promoter following CRISPR/Cas9 directed insertion of luciferase. In this report, we investigated the design criteria to obtain reporters that are specific and responsive to transcription factor (TF) binding and the integration of TF binding activity with genetic reporter activity. The design of TF reporters was investigated for the impact of consensus binding site spacing sequence and off-target binding on the reporter sensitivity using a library of 25 SMAD3 activity reporters with spacers of random composition and length. A spacer was necessary to quantify activity changes after TGFß stimulation. TF binding site prediction algorithms (BEEML, FIMO and DeepBind) were used to predict off-target binding, and nonresponsiveness to a SMAD3 reporter was correlated with a predicted competitive binding of constitutively active p53. The network of activity of the SMAD3 reporter was inferred from measurements of TF reporter library, and connected with large-scale genetic reporter activity measurements. The integration of TF and genetic reporters identified the major hubs directing responses to TGFß, and this method provided a systems-level algorithm to investigate cell signaling.
Subject(s)
Genes, Reporter , Systems Biology/methods , A549 Cells , Algorithms , Binding Sites , Epithelial-Mesenchymal Transition/drug effects , Gene Regulatory Networks/drug effects , Humans , Promoter Regions, Genetic , Research Design , Smad3 Protein/genetics , Transcription Factors/chemistry , Transcription Factors/metabolism , Transforming Growth Factor beta/pharmacology , Tumor Suppressor Protein p53/chemistry , Tumor Suppressor Protein p53/metabolismABSTRACT
Recent research has shown that the microbiome-a collection of microorganisms, including bacteria, fungi, and viruses, living on and in a host-are of extraordinary importance in human health, even from conception and development in the uterus. Therefore, to further our ability to diagnose disease, to predict treatment outcomes, and to identify novel therapeutics, it is essential to include microbiome and microbial metabolic biomarkers in Systems Biology investigations. In clinical studies or, more precisely, Systems Medicine approaches, we can use the diversity and individual characteristics of the personal microbiome to enhance our resolution for patient stratification. In this review, we explore several Systems Medicine approaches, including Microbiome Wide Association Studies to understand the role of the human microbiome in health and disease, with a focus on 'preventive medicine' or P4 (i.e., personalized, predictive, preventive, participatory) medicine.
Subject(s)
Bacteria/classification , Metabolome , Microbiota , Precision Medicine , Systems Biology/methods , Bacteria/metabolism , HumansABSTRACT
Multiple aspects of the local extracellular environment profoundly affect cell phenotype and function. Physical and chemical cues in the environment trigger intracellular signaling cascades that ultimately activate transcription factors (TFs) - powerful regulators of the cell phenotype. TRACER (TRanscriptional Activity CEll aRrays) was employed for large-scale, dynamic quantification of TF activity in human fibroblasts cultured on hydrogels with a controlled elastic modulus and integrin ligand density. We identified three groups of TFs: responders to alterations in ligand density alone, substrate stiffness or both. Dynamic networks of regulatory TFs were constructed computationally and revealed distinct TF activity levels, directionality (i.e., activation or inhibition), and dynamics for adhesive and mechanical cues. Moreover, TRACER networks predicted conserved hubs of TF activity across multiple cell types, which are significantly altered in clinical fibrotic tissues. Our approach captures the distinct and overlapping effects of adhesive and mechanical stimuli, identifying conserved signaling mechanisms in normal and disease states.
Subject(s)
Cellular Microenvironment , Transcription Factors/metabolism , Adhesives , Amino Acid Motifs , Cell Adhesion , Cells, Cultured , Elastic Modulus , Fibroblasts/metabolism , Gene Expression Profiling , Gene Expression Regulation , Gene Regulatory Networks , Genes, Reporter , Humans , Hydrogels/chemistry , Immunohistochemistry , Integrins/metabolism , Ligands , Phenotype , Polyethylene Glycols/chemistry , Probability , Rheology , Signal Transduction , Software , Stress, MechanicalABSTRACT
CONTEXT: A previous genome-wide association study in Chinese women with polycystic ovary syndrome (PCOS) identified a region on chromosome 2p16.3 encoding the LH/choriogonadotropin receptor (LHCGR) and FSH receptor (FSHR) genes as a reproducible PCOS susceptibility locus. OBJECTIVE: The objective of the study was to determine the role of the LHCGR and/or FSHR gene in the etiology of PCOS in women of European ancestry. DESIGN: This was a genetic association study in a European ancestry cohort of women with PCOS. SETTING: The study was conducted at an academic medical center. PARTICIPANTS: Participants in the study included 905 women with PCOS diagnosed by National Institutes of Health criteria and 956 control women. INTERVENTION: We genotyped 94 haplotype-tagging single-nucleotide polymorphisms and two coding single-nucleotide polymorphisms mapping to the coding region of LHCGR and FSHR plus 20 kb upstream and downstream of the genes and test for association in the case control cohort and for association with nine quantitative traits in the women with PCOS. RESULTS: We found strong evidence for an association of PCOS with rs7562215 (P = 0.0037) and rs10495960 (P = 0.0046). Although the marker with the strongest association in the Chinese PCOS genome-wide association study (rs13405728) was not informative in the European populations, we identified and genotyped three markers (rs35960650, rs2956355, and rs7562879) within 5 kb of rs13405728. Of these, rs7562879 was nominally associated with PCOS (P = 0.020). The strongest evidence for association mapping to FSHR was observed with rs1922476 (P = 0.0053). Furthermore, markers with the FSHR gene region were associated with FSH levels in women with PCOS. CONCLUSIONS: Fine mapping of the chromosome 2p16.3 Chinese PCOS susceptibility locus in a European ancestry cohort provides evidence for association with two independent loci and PCOS. The gene products LHCGR and FSHR therefore are likely to be important in the etiology of PCOS, regardless of ethnicity.
Subject(s)
Chromosomes, Human, Pair 2 , Genetic Predisposition to Disease , Polycystic Ovary Syndrome/genetics , White People/genetics , Asian People/genetics , Case-Control Studies , Chromosomes, Human, Pair 2/genetics , Cohort Studies , Female , Genetic Loci , Genetic Predisposition to Disease/ethnology , Genetic Predisposition to Disease/genetics , Genotype , Humans , Linkage Disequilibrium , Polycystic Ovary Syndrome/ethnology , Polymorphism, Single Nucleotide/physiology , Receptors, FSH/genetics , Receptors, LH/genetics , United StatesABSTRACT
Identifying molecular mechanisms or therapeutic targets is typically based on large-scale cellular analysis that measures the abundance of mRNA or protein; however, abundance does not necessarily correlate with activity. We report a method for direct large-scale quantification of active pathways that employs a cellular array with parallel gene delivery of constructs that report pathway activity. The reporter constructs encode luciferase, whose expression is influenced by binding of transcription factors (TFs), which are the downstream targets of signaling pathways. Luciferase levels are quantified by bioluminescence imaging (BLI), which allows for rapid, non-invasive measurements. Activity profiles by BLI of 32 TFs were robust, consistent, and reproducible, and correlated with standard cell lysis techniques. The array identified five TFs with differential activity during phorbol-12-myristate-13-acetate (PMA)-induced differentiation of breast cancer cells. A system for rapid, large-scale, BLI quantification of pathway activity provides an enabling technology for mechanistic studies of cellular responses and processes.
Subject(s)
Gene Expression Profiling , Gene Expression Regulation/drug effects , Metabolic Networks and Pathways/genetics , Microarray Analysis , Transcription Factors/metabolism , Genes, Reporter , Luciferases/metabolism , Luminescent MeasurementsABSTRACT
BACKGROUND: Extracellular activation of signal transduction pathways and their downstream target transcription factors (TFs) are critical regulators of cellular processes and tissue development. The intracellular signaling network is complex, and techniques that quantify the activities of numerous pathways and connect their activities to the resulting phenotype would identify the signals and mechanisms regulating tissue development. The ability to investigate tissue development should capture the dynamic pathway activity and requires an environment that supports cellular organization into structures that mimic in vivo phenotypes. Taken together, our objective was to develop cellular arrays for dynamic, large-scale quantification of TF activity as cells organized into spherical structures within 3D culture. METHODOLOGY/PRINCIPAL FINDINGS: TF-specific and normalization reporter constructs were delivered in parallel to a cellular array containing a well-established breast cancer cell line cultured in Matrigel. Bioluminescence imaging provided a rapid, non-invasive, and sensitive method to quantify luciferase levels, and was applied repeatedly on each sample to monitor dynamic activity. Arrays measuring 28 TFs identified up to 19 active, with 13 factors changing significantly over time. Stimulation of cells with ß-estradiol or activin A resulted in differential TF activity profiles evolving from initial stimulation of the ligand. Many TFs changed as expected based on previous reports, yet arrays were able to replicate these results in a single experiment. Additionally, arrays identified TFs that had not previously been linked with activin A. CONCLUSIONS/SIGNIFICANCE: This system provides a method for large-scale, non-invasive, and dynamic quantification of signaling pathway activity as cells organize into structures. The arrays may find utility for investigating mechanisms regulating normal and abnormal tissue growth, biomaterial design, or as a platform for screening therapeutics.