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Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. It is well known that repeated inflammatory insults in the liver can cause hepatic cellular injury that lead to cirrhosis and, ultimately, hepatocellular carcinoma. Furthermore, the microbiome has been implicated in multiple inflammatory conditions which predispose patients to malignancy. With this in mind, we explore the inflammatory implications of the microbiome on pathways that lead to HCC. We also focus on how an understanding of these underlying inflammatory principles lead to a more wholistic understanding of this deadly disease, as well as potential therapeutic implications.

Colorectal cancer is one of the most commonly diagnosed cancers worldwide. Traditionally, mechanisms of colorectal cancer formation have focused on genetic alterations including chromosomal damage and microsatellite instability. In recent years, there has been a growing body of evidence supporting the role of inflammation in colorectal cancer formation. Multiple cytokines, immune cells such T cells and macrophages, and other immune mediators have been identified in pathways leading to the initiation, growth, and metastasis of colorectal cancer. Outside the previously explored mechanisms and pathways leading to colorectal cancer, initiatives have been shifted to further study the role of inflammation in pathogenesis. Inflammatory pathways have also been linked to some traditional risk factors of colorectal cancer such as obesity, smoking and diabetes, as well as more novel associations such as the gut microbiome, the gut mycobiome and exosomes. In this review, we will explore the roles of obesity and diet, smoking, diabetes, the microbiome, the mycobiome and exosomes in colorectal cancer, with a specific focus on the underlying inflammatory and metabolic pathways involved. We will also investigate how the study of colon cancer from an inflammatory background not only creates a more holistic and inclusive understanding of this disease, but also creates unique opportunities for prevention, early diagnosis and therapy.

TOPIC: Cardiovascular Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: Immunosuppressive therapy is essential for organ transplanted patients. One such broadly used agent is the commonly used macrolide antibiotic tacrolimus. Tacrolimus has several well-known adverse effects including nephrotoxicity, neurotoxicity, infection, diarrhea. Reports of supraventricular tachycardia as a side effect of tacrolimus are rare. CASE PRESENTATION: We present a 48-year-old male with a history of non-ischemic cardiomyopathy status post orthotopic heart transplant who presented to the hospital due to sudden onset palpitations with mild diaphoresis which lasted 30 minutes in duration. Patient reported some mild diaphoresis but no shortness of breath, chest pain, lightheadedness, or dizziness. The patient stated that he had been experiencing episodes of tachycardia for the last few months but none that had persisted to this extent. He reported medication compliance. His vitals were Temp 98.4, BP 140/88, HR 260, RR 20. After review of his EKG, he was diagnosed with supraventricular tachycardia (SVT) (referenced EKG is after adenosine administration). The patient was hospitalized a few months prior to admission for COVID 19 infection and acute pulmonary embolism. His transplant antirejection regimen was changed from sirolimus to tacrolimus during this prior hospitalization due to the increased risk of thrombosis associated with sirolimus in view of the recognized prothrombic effects of COVID-19. Incidentally, the patient started experiencing sporadic episodes of tachycardia since this change in his medication regimen. In the emergency department, diagnostic studies such as troponins, CBC, BMP, magnesium, hepatic panel, TSH, CMV DNA were within normal parameters for the patient. Tacrolimus blood concentration level was found to be 17 with a goal normal level between 4 to 6. The patient had a right/left heart catheterization with endomyocardial biopsy which showed no evidence of coronary artery vasculopathy or acute cellular rejection, thereby ruling out other potential causes of his SVT. His tacrolimus dose was subsequently decreased with significant improvement in the frequency of his symptoms and no further reported episodes of SVT (with further tacrolimus levels not exceeding 7). DISCUSSION: The mechanism by which tacrolimus leads to SVT is not well understood. One purported mechanism is through the inhibition of the calcineurin-calcium-calmodulin complex. Calcium calmodulin is coincidentally also used by smooth muscle cells to contract. It is thought that by inhibiting this system, there is a subsequent increase in vasodilation which leads to the increased sympathetic and adrenergic response, thereby increasing the risk of arrhythmias such as SVT. CONCLUSIONS: Incessant dysrhythmias caused by tacrolimus can be life-threatening, whereby we seek to raise awareness of the importance of carefully monitoring patients on this drug. REFERENCE #1: Kim BR, Shin HS, Jung YS, Rim H. A case of tacrolimus-induced supraventricular arrhythmia after kidney transplantation. Sao Paulo Med J. 2013;131(3):205-207. doi:10.1590/1516-3180.2013.1313472 REFERENCE #2: Pires SDS, Oliveira R, Moradas-Ferreira P, Mendes MV. The Onset of Tacrolimus Biosynthesis in Streptomyces tsukubaensis Is Dependent on the Intracellular Redox Status. Antibiotics (Basel). 2020;9(10):703. Published 2020 Oct 15. doi:10.3390/antibiotics9100703 REFERENCE #3: Wojciechowski D, Wiseman A. Long-Term Immunosuppression Management: Opportunities and Uncertainties [published online ahead of print, 2021 Apr 14]. Clin J Am Soc Nephrol. 2021;CJN.15040920. doi:10.2215/CJN.15040920 DISCLOSURES: No relevant relationships by Jamarcus Brider, source=Web Response No relevant relationships by Ahamed Khalyfa, source=Web Response No relevant relationships by Navkiran Randhawa, source=Web Response

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Guillain Barre Syndrome (GBS) is a syndrome usually consisting of paralyzing illness following an infectious process. SARS-COV-2 virus has well documented complications including pneumonia, ARDS, nephropathy, and thrombosis. Neurologic sequelae of GBS, as described in our case are much less common (1). CASE PRESENTATION: An 85-year-old African American male with recent COVID-19 infection, who presented to the emergency department with bilateral lower extremity weakness and bilateral upper extremity tingling for 24 hours. Vital signs were stable on admission. Physical exam revealed quadriparesis and sensory loss, areflexia of L4 and S1 and no saddle anesthesia. MRI brain and cervical spine revealed no signs of myelitis. Due to concern for COVID-19 post viral syndrome in the setting of new, rapidly progressing neurological symptoms, IVIG therapy was initiated. An EMG study was performed and was consistent with length dependent sensory and motor polyneuropathy, with mixed demyelinating and axonal features. Furthermore, there was minimal to absent recruitment of most muscles, consistent with high severity of disease. Patient's condition continued to worsen. He was intubated and placed on mechanical ventilatory support. While on mechanical ventilation, plasma exchange (PLEX) was initiated with subsequent improvement of his symptoms. Eventually, he was transferred to acute inpatient rehab to continue recovery. DISCUSSION: The most common peripheral nervous system manifestations of COVID-19 usually involve anosmia and chemosensory dysfunction (2). Case reports have shown an association between COVID-19 and GBS. It remains unclear whether humoral molecular mimicry, as seen in C. Jejuni, is also the driving mechanism behind the pathogenesis of GBS in SARS-CoV-2 (3). Reports have highlighted that no known SARS-CoV-2 epitopes have been found to be homologically similar to human peripheral nerve tissue and therefore unable to support immune driven, previously widely described molecular mechanisms of GBS (4). However, this lack of clear genetic similarity does not exclude immune mediated response as it's possible that immunogenic proteins could be modified post-translationally or have non-linear antibody epitopes driving such response (5). In addition, although there has been no evidence of SARS-CoV-2 detection in CSF (6), a small sample size of CSF studies from COVID 19 patients likely points towards overall inflammation caused by virus leading to immune cascade and possible infiltration of immune cells locally leading to CNS injury (7). CONCLUSIONS: Clinicians treating COVID-19 viral syndromes should be aware of the association between COVID-19 and GBS, especially when caring for patients with rapidly progressing neurologic disease. Further work needs to be done to broaden the understanding of pathogenesis of GBS in such cases. REFERENCE #1: Montalvan V, Lee J, Bueso T et al. Neurological manifestations of COVID-19 and other coronavirus infections: A systematic review. Clinical Neurology and Neurosurgery 194. REFERENCE #2: Lechner M, Chandrasekharan D, Jumani K, Liu et al. Anosmia as a presenting symptom of SARS-CoV-2 infection in healthcare workers - A systematic review of the literature, case series, and recommendations for clinical assessment and management. Rhinology. 2020 Aug 1;58(4):394-399. REFERENCE #3: Loshaj-Shala A, Regazzoni L, Daci A, Orioli M, Brezovska K, Panovska AP, et al. Guillain Barre syndrome (GBS): new insights in the molecular mimicry between C. Jejuni and human peripheral nerve (HPN) proteins. J Neuroimmunology 2015;289: 168–76. DISCLOSURES: No relevant relationships by Mateusz Gorecki, source=Web Response no disclosure on file for Dean Kalam;No relevant relationships by Ahamed Khalyfa, source=Web Response

Intermittent hypoxia (IH) induces activation of the integrated stress response (ISR), but its role in IH-induced visceral white adipose tissue (vWAT) insulin resistance is unknown. CHOP is activated by chronic ISR, whereas GADD34 dephosphorylates the subunit of translation initiation factor 2 (eIF2α), leading to termination of the ISR. We hypothesized that CHOP/Gadd34 null mice would not manifest evidence of insulin resistance after IH exposures. Eight-week-old CHOP/GADD34−/− (double mutant [DM]) and wild-type (WT) littermates were randomly assigned to IH or room air (RA) exposures for 6 weeks. Glucose and insulin tolerance tests were performed, and regulatory T cells (Tregs) and macrophages in vWAT were assessed. Phosphorylated eIF2α:total eIF2α, ATF4, XBP1 expression, and insulin-induced pAKT/AKT expression changes were examined in vWATs. Single GADD34−/− and PERK+/− mice were also evaluated. Body weight and vWAT mass were reduced in DM and WT mice after IH. M1/M2 macrophages and inflammatory macrophages (Ly-6chigh) were significantly increased in WT vWAT but remained unchanged in DM mice. Tregs were significantly decreased in WT vWAT but not in DM mice. Systemic insulin and glucose tolerance tests revealed insulin resistance in IH-WT but not in IH-DM mice. Similarly, decreased pAKT/AKT responses to exogenous insulin emerged in IH-WT compared with RA-WT mice, whereas no significant differences emerged in IH-DM compared with DM-RA. Chronic ISR activation appears to contribute to the insulin resistance and vWAT inflammation that characteristically emerge after long-term IH exposures in a murine model of obstructive sleep apnea.

STUDY OBJECTIVES: Longitudinal studies support the usage of positive airway pressure (PAP) therapy in treating obstructive sleep apnea (OSA) to improve cardiovascular disease. However, the anticipated benefit is not ubiquitous. In this study, we elucidate whether PAP therapy leads to immediate improvements on endothelial function, a subclinical marker of cardiovascular status, by examining the effect of circulating exosomes, isolated from patients before and after PAP therapy, on naive endothelial cells. METHODS: We isolated plasma-derived circulating exosomes from 12 patients with severe OSA and obesity hypoventilation syndrome (OHS) before and after 6 weeks of PAP therapy, and examined their effect on cultured endothelial cells using several in vitro reporter assays. RESULTS: We found that circulating exosomes contributed to the induction and propagation of OSA/OHS-related endothelial dysfunction (ie, increased permeability and disruption of tight junctions along with increased adhesion molecule expression, and reduced endothelial nitric oxide synthase expression), and promoted increased monocyte adherence. Further, when comparing exosomes isolated before and after PAP therapy, the disturbances in endothelial cell function were attenuated with treatment, including an overall cumulative decrease in endothelial permeability in all 12 subjects by 10.8% (P = .035), as well as detection of a subset of 4 differentially expressed exosomal miRNAs, even in the absence of parallel changes in systemic blood pressure or metabolic function. CONCLUSIONS: Circulating exosomes facilitate important intercellular signals that modify endothelial phenotype, and thus emerge as potential fundamental contributors in the context of OSA/OHS-related endothelial dysfunction. Exosomes may not only provide candidate biomarkers, but are also a likely and plausible mechanism toward OSA/OHS-induced cardiovascular disease. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov, Title: AVAPS-AE Efficacy Study, URL: https://clinicaltrials.gov/ct2/show/NCT01368614, Identifier: NCT01368614 CITATION: Bhattacharjee R, Khalyfa A, Khalyfa AA, Mokhlesi B, Kheirandish-Gozal L, Almendros I, Peris E, Malhotra A, Gozal D. Exosomal cargo properties, endothelial function and treatment of obesity hypoventilation syndrome: a proof of concept study. J Clin Sleep Med. 2018;14(5):797–807.

Sleep fragmentation (SF) is a common condition among pregnant women, particularly during late gestation. Gestational perturbations promote the emergence of adiposity and metabolic disease risk in offspring, most likely through epigenetic modifications. Adiponectin (AdipoQ) expression inversely correlates with obesity and insulin resistance. The effects of SF during late gestation on metabolic function and AdipoQ expression in visceral white adipose tissue (VWAT) of offspring mice are unknown. Male offspring mice were assessed at 24 weeks after dams were exposed to SF or control sleep during late gestation. Increased food intake, body weight, VWAT mass, and insulin resistance, with reductions in AdipoQ expression in VWAT, emerged in SF offspring. Increased DNMT3a and -b and global DNA methylation and reduced histone acetyltransferase activity and TET1, -2, and -3 expression were detected in VWAT of SF offspring. Reductions in 5-hydroxymethylcytosine and H3K4m3 and an increase in DNA 5-methylcytosine and H3K9m2 in the promoter and enhancer regions of AdipoQ emerged in adipocytes from VWAT and correlated with AdipoQ expression. SF during late gestation induces epigenetic modifications in AdipoQ in male offspring mouse VWAT adipocytes along with a metabolic syndrome–like phenotype. Thus, altered gestational environments elicited by SF impose the emergence of adverse, long-lasting metabolic consequences in the next generation.

Obese children are at increased risk for developing obstructive sleep apnea (OSA), and both of these conditions are associated with an increased risk for endothelial dysfunction (ED) in children, an early risk factor for atherosclerosis and cardiovascular disease. Although weight loss and treatment of OSA by adenotonsillectomy improve endothelial function, not every obese child or child with OSA develops ED. Exosomes are circulating extracellular vesicles containing functional mRNA and microRNA (miRNA) that can be delivered to other cells, such as endothelial cells.To investigate whether circulating exosomal miRNAs of children with OSA differentiate based on endothelial functional status.Obese children (body mass index z score1.65) and nonobese children were recruited and underwent polysomnographic testing (PSG), and fasting endothelial function measurements and blood draws in the morning after PSG. Plasma exosomes were isolated from all subjects. Isolated exosomes were then incubated with confluent endothelial cell monolayer cultures. Electric cell-substrate impedance sensing systems were used to determine the ability of exosomes to disrupt the intercellular barrier formed by confluent endothelial cells. In addition, immunofluorescent assessments of zonula occludens-1 tight junction protein cellular distribution were conducted to examine endothelial barrier dysfunction. miRNA and mRNA arrays were also applied to exosomes and endothelial cells, and miRNA inhibitors and mimics were transfected for mechanistic assays.Plasma exosomes isolated from either obese children or nonobese children with OSA were primarily derived from endothelial cell sources and recapitulated ED, or its absence, in naive human endothelial cells and also in vivo when injected into mice. Microarrays identified a restricted signature of exosomal miRNAs that readily distinguished ED from normal endothelial function. Among the miRNAs, expression of exosomal miRNA-630 was reduced in children with ED and normalized after therapy along with restoration of endothelial function. Conversely, transfection of exosomes from subjects without ED with an miRNA-630 inhibitor induces the ED functional phenotype. Gene target discovery experiments further revealed that miRNA-630 regulates 416 gene targets in endothelial cells that include the Nrf2, AMP kinase, and tight junction pathways.These observations elucidate a novel role of exosomal miRNA-360 as a putative key mediator of vascular function and cardiovascular disease risk in children with underlying OSA and/or obesity, and identify therapeutic targets.

Obstructive sleep apnea (OSA) affects 8–10% of the population, is characterized by chronic intermittent hypoxia (CIH), and causally associates with cardiovascular morbidities. In CIH-exposed mice, closely mimicking the chronicity of human OSA, increased accumulation and proliferation of pro-inflammatory metabolic M1-like macrophages highly expressing CD36, emerged in aorta. Transcriptomic and MeDIP-seq approaches identified activation of pro-atherogenic pathways involving a complex interplay of histone modifications in functionally-relevant biological pathways, such as inflammation and oxidative stress in aorta macrophages. Discontinuation of CIH did not elicit significant improvements in aorta wall macrophage phenotype. However, CIH-induced aorta changes were absent in CD36 knockout mice, Our results provide mechanistic insights showing that CIH exposures during sleep in absence of concurrent pro-atherogenic settings (i.e., genetic propensity or dietary manipulation) lead to the recruitment of CD36(+)high macrophages to the aortic wall and trigger atherogenesis. Furthermore, long-term CIH-induced changes may not be reversible with usual OSA treatment.

International audience; Sickle cell anaemia (SCA) is the most frequent genetic haemoglobinopathy, which exhibits a highly variable clinical course characterized by hyper-coagulable and pro-inflammatory states, as well as endothelial dysfunction. Extracellular microvesicles are released into biological fluids and play a role in modifying the functional phenotype of target cells. We hypothesized that potential differences in plasma-derived extracellular microvesicles (EV) function and cargo from SCA patients may underlie divergent clinical trajectories. Plasma EV from SCA patients with mild, intermediate and severe clinical disease course were isolated, and primary endothelial cell cultures were exposed. Endothelial cell activation, monocyte adhesion, barrier disruption and exosome cargo (microRNA microarrays) were assessed. EV disrupted the endothelial barrier and induced expression of adhesion molecules and monocyte adhesion in a SCA severity-dependent manner compared to healthy children. Microarray approaches identified a restricted signature of exosomal microRNAs that readily distinguished severe from mild SCA, as well as from healthy children. The microRNA candidates were further validated using quantitative real time polymerase chain reaction assays, and revealed putative gene targets. Circulating exosomal microRNAs may play important roles in predicting the clinical course of SCA, and in delineation of individually tailored, mechanistically-based clinical treatment approaches of SCA patients in the near future.

Study objective Intermittent hypoxia (IH) is associated with increased risk of cardiovascular disease. Exosomes are secreted by most cell types and released in biological fluids, including plasma, and play a role in modifying the functional phenotype of target cells. Using an experimental human model of IH, we investigated potential exosome-derived biomarkers of IH-induced vascular dysfunction. Methods Ten male volunteers were exposed to room air (D0), IH (6 h/day) for 4 days (D4) and allowed to recover for 4 days (D8). Circulating plasma exosomes were isolated and incubated with human endothelial monolayer cultures for impedance measurements and RNA extracted and processed with messenger RNA (mRNA) arrays to identify gene targets. In addition, immunofluorescent assessments of endothelial nitric oxide synthase (eNOS) mRNA expression, ICAM-1 cellular distribution were conducted. Results Plasma exosomal micro RNAs (miRNAs) were profiled. D4 exosomes, primarily from endothelial sources, disrupted impedance levels compared to D0 and D8. ICAM-1 expression was markedly upregulated in endothelial cells exposed to D4 exosomes along with significant reductions in eNOS expression. Microarray approaches identified a restricted and further validated signature of exosomal miRNAs in D4 exosomes, and mRNA arrays revealed putative endothelial gene target pathways. Conclusions In humans, intermittent hypoxia alters exosome cargo in the circulation which promotes increased permeability and dysfunction of endothelial cells in vitro. A select number of circulating exosomal miRNAs may play important roles in the cardiovascular dysfunction associated with OSA by targeting specific effector pathways.

Cardiovascular disease (CVD) is a complex disease with multifactorial etiology. The presence of endothelial dysfunction constitutes an early risk factor for CVD in children. Circulating microRNAs (miRNAs) are small noncoding RNAs that regulate gene expression and represent a novel class of biomarkers and therapeutic targets; therefore, we examined whether the presence of endothelial dysfunction is associated with differential expression of plasma miRNAs in otherwise healthy children.A total of 70 children (aged 5-10 years) were recruited and classified into two groups (normal endothelial function [NEF] and endothelial dysfunction). Time to peak postocclusive reperfusion (Tmax) was considered as the indicator of either normal endothelial function (NEF; Tmax45 s) or endothelial dysfunction (Tmax ≥ 45 s). Lipid profiles, high-sensitivity C-reactive protein, fasting glucose, and insulin were assayed using enzyme-linked immunosorbent assay. miRNAs isolated from plasma were assayed with a custom human CVD array, followed by quantitative polymerase chain reaction verification of candidates. In addition, bioinformatics approaches including combinatorial target prediction algorithms and gene ontology were applied.Three miRNAs that have been previously linked to cardiomyopathy, hsa-miR-125a-5p, hsa-miR-342-3p, and hsa-miR-365b-3p, were identified as potential biomarkers of children with endothelial dysfunction. The miRNA predicted gene targets revealed 31 common targets among all three putative candidate biomarker miRNAs and encompass three biologic pathways, including transforming growth factor-β signaling, cytokine-cytokine receptor interactions, and activin receptor-like kinase in cardiac myocytes.Plasma miRNAs may be useful as potential screening tools for the presence of endothelial dysfunction in children and may reveal endothelial dysfunction-relevant target genes.

Introduction La grossesse s’accompagne de facon frequente d’une fragmentation du sommeil (FS) en particulier chez les femmes obeses et au cours du dernier trimestre en rapport avec une prevalence accrue des troubles respiratoires nocturnes. Cette FS gestationnelle peut induire une obesite et une dysfonction metabolique au sein de la progeniture adulte. Par ailleurs, la FS peut induire une reponse integree au stress, cascade moleculaire intracellulaire pouvant aboutir a des perturbations metaboliques. Nous avons emis l’hypothese que la descendance de souris presentant une mutation de deux genes impliques dans la reponse integree au stress (CHOP et GADD34) serait protegee des consequences metaboliques de la FS gestationnelle. Methodes Des souris enceintes presentant la double mutation (DM) CHOP et GADD34 et des souris enceintes sauvages (SA) ont ete soumises a une FS pendant les 5 derniers jours de la grossesse ou a des conditions de sommeil normal (SN). Le poids des animaux et de la graisse viscerale ainsi que l’index HOMA-IR ont ete etudies au sein de la descendance a l’âge de 24 semaines. Les lymphocytes Treg ainsi que les macrophages M1, M2 et Lyc6chigh ont ete analyses par cryometrie en flux dans la graisse viscerale des animaux. L’impact des exosomes plasmatiques issues des animaux de la descendance sur la proliferation, la differenciation adipocytaire et la sensibilite a l’insuline in vitro a ete evaluee. Resultats Les souris FS-SA mâles presentaient une augmentation du poids total, de la masse de graisse viscerale et de l’HOMA-IR par rapport aux souris SN-SA alors que la FS n’avait aucun impact sur ces parametres chez les souris DM. Le nombre de macrophages pro-inflammatoires Ly-6chigh et le ratio M1/M2 etaient augmentes alors que le nombre de macrophages FoxP3+ Tregs etait diminue chez les souris FS-SA mais non modifies chez les souris FS-DM. Les exosomes issus des animaux FS-SA entrainaient une augmentation de la proliferation et de la differentiation adipocytaire et une diminution de la sensibilite a l’insuline in vitro. La FS ne modifiait pas l’impact in vitro des exosomes issus des souris DM sur ces derniers parametres. Conclusion L’activation de la reponse integree au stress par la FS gestationnelle participe au developpement d’un profil dysmetabolique au sein de la descendance adulte et les exosomes plasmatiques retiennent quelques-unes de ces proprietes. Leur contenu en ARN et ADN est donc susceptible de reveler quelques-uns des mecanismes impliques.

Background The presence of endothelial dysfunction (ED) constitutes an early risk factor for cardiovascular disease (CVD) in children. Nitric oxide (NO) and endothelin (EDN) are generated in endothelial cells and are critical regulators of vascular function, with ED resulting from an imbalance between these two molecules. We hypothesized that genetic variants in NO synthase and EDN isoforms and its receptors (EDNRA and EDNRB) may account for a proportion of the risk for ED in developing children. Methods Consecutive children (ages 5–10 years) were prospectively recruited from the community. Time to peak post-occlusive reperfusion (Tmax) was considered as the indicator of either normal endothelial function (NEF; Tmax < 45 sec) or ED (Tmax ≥ 45 sec). Lipid profiles, high sensitivity C-reactive protein (hsCRP), fasting glucose and insulin were assayed using ELISA. Genomic DNA from peripheral blood was extracted and genotyped for NOS1 (209 SNPs), NOS2 (122 SNPs), NOS3 (50 SNPs), EDN1 (43 SNPs), EDN2 (48 SNPs), EDN3 (14 SNPs), EDNRA (27 SNPs), and EDNRB (23 SNPs) using a custom SNPs array. Linkage disequilibrium was analyzed using Haploview version 4.2 software. Results The relative frequencies of SNPs were evaluated in 122 children, 84 with NEF and 38 with ED. The frequencies of NOS1 (11 SNPs), and EDN1 (2 SNPs) were differentially distributed between NEF vs. ED, and no significant differences emerged for all other genes. Significant SNPs for NOS1 and EDN1 SNPs were further validated with RT-PCR. Conclusions Genetic variants in the NOS1 and EDN1 genes appear to account for important components of the variance in endothelial function, particularly when concurrent risk factors such as obesity exist. Thus, analysis of genotype-phenotype interactions in children at risk for ED will be critical for more accurate formulation of categorical CVD risk estimates.

Background Obstructive sleep apnea (OSA) is associated with adverse and interdependent cognitive and cardiovascular consequences. Increasing evidence suggests that nitric oxide synthase (NOS) and endothelin family (EDN) genes underlie mechanistic aspects of OSA-associated morbidities. We aimed to identify single nucleotide polymorphisms (SNPs) in the NOS family (3 isoforms), and EDN family (3 isoforms) to identify potential associations of these SNPs in children with OSA. Methods A pediatric community cohort (ages 5–10 years) enriched for snoring underwent overnight polysomnographic (NPSG) and a fasting morning blood draw. The diagnostic criteria for OSA were an obstructive apnea-hypopnea Index (AHI) >2/h total sleep time (TST), snoring during the night, and a nadir oxyhemoglobin saturation NOS1 (209 SNPs), NOS2 (122 SNPs), NOS3 (50 SNPs), EDN1 (43 SNPs), EDN2 (48 SNPs), EDN3 (14 SNPs), endothelin receptor A, EDNRA, (27 SNPs), and endothelin receptor B, EDNRB (23 SNPs) using a custom SNPs array. The relative frequencies of NOS-1,-2, and −3, and EDN-1,-2,-3,-EDNRA, and-EDNRB genotypes were evaluated in 608 subjects [128 with OSA, and 480 without OSA (NOSA)]. Furthermore, subjects with OSA were divided into 2 subgroups: OSA with normal endothelial function (OSA-NEF), and OSA with endothelial dysfunction (OSA-ED). Linkage disequilibrium was analyzed using Haploview version 4.2 software. Results For NOSA vs. OSA groups, 15 differentially distributed SNPs for NOS1 gene, and 1 SNP for NOS3 emerged, while 4 SNPs for EDN1 and 1 SNP for both EDN2 and EDN3 were identified. However, in the smaller sub-group for whom endothelial function was available, none of the significant SNPs was retained due to lack of statistical power. Conclusions Differences in the distribution of polymorphisms among NOS and EDN gene families suggest that these SNPs could play a contributory role in the pathophysiology and risk of OSA-induced cardiovascular morbidity. Thus, analysis of genotype-phenotype interactions in children with OSA may assist in the formulation of categorical risk estimates.

Pediatric obstructive sleep apnea (OSA) may lead to neurocognitive dysfunction, but not in everyone affected. The frequencies of NADPH oxidase (NOX) polymorphisms in the p22phox subunit were similar between children with OSA and controls, except for rs6520785 and rs4673, the latter being significantly more frequent among the OSA children without deficits than with deficits (p

Introduction Obstructive sleep apnea (OSA) is a common health problem, particularly in obese children, in whom a vicious cycle of obesity and OSA interdependencies promote increased food intake. GPR120 is a long-chain free fatty acid (FFA) receptor that plays an important role in energy homeostasis, and protects from insulin resistance and systemic inflammation. Thus, we hypothesized that GPR120 levels would be reduced in children with OSA, particularly among obese children. Materials and methods 226 children (mean age: 7.0 ± 2.1years) underwent overnight polysomnographic evaluation and a fasting blood draw the morning after the sleep study. In addition to lipid profile, HOMA-IR and hsCRP assays, monocyte GPR120 expression and plasma GPR120 levels were assessed using qPCR and ELISA kits. Results Obese children and OSA children had significantly lower GPR120 monocyte expression and plasma GPR120 levels. Furthermore, when both obesity and OSA were concurrently present, GRP120 levels were lowest. Linear associations emerged between GRP120 plasma levels and BMI z score, as well as with AHI, SpO2 nadir, and respiratory arousal index, the latter remaining statistically significant when controlling for age, ethnicity, gender, and BMI z score ( p 0.001). Similarly, HOMA-IR was significantly associated with GRP120 levels, but neither LDL nor HDL cholesterol or hsCRP levels exhibited significant correlations. Conclusion GPR120 levels are reduced in pediatric OSA and obesity, particularly when both are present, and may play a role in modulating the degree of insulin resistance. The short-term and long-term significance of reduced GPR120 in food intake and glycemic deregulation remains undefined. Acknowledgements Supported by National Institutes of Health grants HL-65270, HL-086662, and HL- 107160.

Chronic sleep fragmentation (SF) commonly occurs in human populations, and although it does not involve circadian shifts or sleep deprivation, it markedly alters feeding behaviors ultimately promoting obesity and insulin resistance. These symptoms are known to be related to the host gut microbiota. Mice were exposed to SF for 4 weeks and then allowed to recover for 2 weeks. Taxonomic profiles of fecal microbiota were obtained prospectively, and conventionalization experiments were performed in germ-free mice. Adipose tissue insulin sensitivity and inflammation, as well as circulating measures of inflammation, were assayed. Effect of fecal water on colonic epithelial permeability was also examined. Chronic SF-induced increased food intake and reversible gut microbiota changes characterized by the preferential growth of highly fermentative members of Lachnospiraceae and Ruminococcaceae and a decrease of Lactobacillaceae families. These lead to systemic and visceral white adipose tissue inflammation in addition to altered insulin sensitivity in mice, most likely via enhanced colonic epithelium barrier disruption. Conventionalization of germ-free mice with SF-derived microbiota confirmed these findings. Thus, SF-induced metabolic alterations may be mediated, in part, by concurrent changes in gut microbiota, thereby opening the way for gut microbiome-targeted therapeutics aimed at reducing the major end-organ morbidities of chronic SF.