Insular cortex neurons encode and retrieve specific immune responses

Increasing evidence indicates that the brain regulates peripheral immunity, yet whether and how the brain represents the state of the immune system remains unclear. Here, we show that the brain's insular cortex (InsCtx) stores immune-related information. Using activity-dependent cell labeling in mice (Fos^TRAP), we captured neuronal ensembles in the InsCtx that were active under two different inflammatory conditions (dextran sulfate sodium [DSS]-induced colitis and zymosan-induced peritonitis). Chemogenetic reactivation of these neuronal ensembles was sufficient to broadly retrieve the inflammatory state under which these neurons were captured. Thus, we show that the brain can store and retrieve specific immune responses, extending the classical concept of immunological memory to neuronal representations of inflammatory information.

Intermittent hypoxia-induced changes in tumor-associated macrophages and tumor malignancy in a mouse model of sleep apnea

RATIONALE

An increased cancer aggressiveness and mortality have been recently reported among patients with obstructive sleep apnea (OSA). Intermittent hypoxia (IH), a hallmark of OSA, enhances melanoma growth and metastasis in mice.

OBJECTIVES

To assess whether OSA-related adverse cancer outcomes occur via IH-induced changes in host immune responses, namely tumor-associated macrophages (TAMs).

MEASUREMENTS AND MAIN RESULTS

Lung epithelial TC1 cell tumors were 84% greater in mice subjected to IH for 28 days compared with room air (RA). In addition, TAMs in IH-exposed tumors exhibited reductions in M1 polarity with a shift toward M2 protumoral phenotype. Although TAMs from tumors harvested from RA-exposed mice increased TC1 migration and extravasation, TAMs from IH-exposed mice markedly enhanced such effects and also promoted proliferative rates and invasiveness of TC1 cells. Proliferative rates of melanoma (B16F10) and TC1 cells exposed to IH either in single culture or in coculture with macrophages (RAW 264.7) increased only when RAW 264.7 macrophages were concurrently present.

CONCLUSIONS

Our findings support the notion that IH-induced alterations in TAMs participate in the adverse cancer outcomes reported in OSA.

Development of disease and virus recovery in transgenic mice containing HIV proviral DNA

Transgenic mice containing intact copies of the human immunodeficiency virus (HIV) proviral DNA were constructed. Founder animals were not viremic for HIV and remained healthy during a 9-month observation period. After being mated with nontransgenic animals, one founder mouse (No. 13) gave rise to F1 progeny that developed a disease syndrome characterized by marked epidermal hyperplasia, lymphadenopathy, splenomegaly, pulmonary lymphoid infiltrates, growth retardation, and death by day 25 of life. Infectious HIV, indistinguishable from parental virus by immunoblot analysis, was recovered from the spleen, lymph nodes, and skin of five of five affected animals.

Sleep fragmentation induces cognitive deficits via nicotinamide adenine dinucleotide phosphate oxidase-dependent pathways in mouse

RATIONALE

Sleep fragmentation (SF) is one of the major characteristics of sleep apnea, and has been implicated in its morbid consequences, which encompass excessive daytime sleepiness and neurocognitive impairments. We hypothesized that absence of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity is neuroprotective in SF-induced cognitive impairments.

OBJECTIVES

To examine whether increased NADPH oxidase activity may play a role in SF-induced central nervous system dysfunction.

METHODS

The effect of chronic SF during the sleep-predominant period on sleep architecture, sleep latency, spatial memory, and oxidative stress parameters was assessed in mice lacking NADPH oxidase activity (gp91phox-(/Y)) and wild-type littermates.

MEASUREMENTS AND MAIN RESULTS

SF for 15 days was not associated with differences in sleep duration, sleep state distribution, or sleep latency in both gp91phox-(/Y) and control mice. However, on a standard place training task, gp91phox-(/Y) mice displayed normal learning and were protected from the spatial learning deficits observed in wild-type littermates exposed to SF. Moreover, anxiety levels were increased in wild-type mice exposed to SF, whereas no changes emerged in gp91phox-(/Y) mice. Additionally, wild-type mice, but not gp91phox-(/Y) mice, had significantly elevated NADPH oxidase gene expression and activity, and in malondialdehyde and 8-oxo-2'-deoxyguanosine levels in cortical and hippocampal lysates after SF exposures.

CONCLUSIONS

This work substantiates an important role for NADPH oxidase in hippocampal memory impairments induced by SF, modeling sleep apnea. Targeting NADPH oxidase, therefore, is expected to minimize hippocampal impairments from both intermittent hypoxia and SF associated with the disease.

Fragmented sleep accelerates tumor growth and progression through recruitment of tumor-associated macrophages and TLR4 signaling

Sleep fragmentation (SF) is a highly prevalent condition and a hallmark of sleep apnea, a condition that has been associated with increased cancer incidence and mortality. In this study, we examined the hypothesis that sleep fragmentation promotes tumor growth and progression through proinflammatory TLR4 signaling. In the design, we compared mice that were exposed to sleep fragmentation one week before engraftment of syngeneic TC1 or LL3 tumor cells and tumor analysis four weeks later. We also compared host contributions through the use of mice genetically deficient in TLR4 or its effector molecules MYD88 or TRIF. We found that sleep fragmentation enhanced tumor size and weight compared with control mice. Increased invasiveness was apparent in sleep fragmentation tumors, which penetrated the tumor capsule into surrounding tissues, including adjacent muscle. Tumor-associated macrophages (TAM) were more numerous in sleep fragmentation tumors, where they were distributed in a relatively closer proximity to the tumor capsule compared with control mice. Although tumors were generally smaller in both MYD88(-/-) and TRIF(-/-) hosts, the more aggressive features produced by sleep fragmentation persisted. In contrast, these more aggressive features produced by sleep fragmentation were abolished completely in TLR4(-/-) mice. Our findings offer mechanistic insights into how sleep perturbations can accelerate tumor growth and invasiveness through TAM recruitment and TLR4 signaling pathways.

Transcatheter closure of single muscular ventricular septal defects using the amplatzer muscular VSD occluder: initial results and technical considerations

Surgical closure of multiple muscular ventricular septal defects (MVSDs) is associated with mortality and morbidity; therefore, both surgeons and cardiologists welcome a nonsurgical safe approach. We report our initial results of catheter closure of MVSD using the new Amplatzer muscular VSD occluder delivered via the venous or arterial routes. Eight patients with MVSD underwent closure of their VSDs using the Amplatzer VSD occluder under general endotracheal anesthesia. The mean +/- SD of age was 5.4 +/- 3.1 years (2-10 years) and mean weight was 18.4 +/- 6.5 kg (11.5-29 kg). All patients had left ventricular volume overload with mean Qp/Qs ratio of 1.7 +/- 0.6 (1.4-3). The location of the VSD was mid muscular in four, anterior in two, apical in one, and posterior in one. The systolic pulmonary artery pressure ranged from 25 to 85 mm Hg (mean, 39.9 +/- 18.8 mm Hg). The device was implanted successfully in all eight patients. In five patients (four mid muscular and one apical), the deployment of the device was anterograde from the right internal jugular vein and in three patients (two anterior and one posterior VSD), the initial attempt at anterograde deployment was unsuccessful due to kinking in the delivery sheath; therefore, retrograde deployment was attempted successfully. The size of the device used ranged from 6 to 14 mm (the size of the connecting waist). In patients with elevated pulmonary artery pressure, repeat measurements immediately after closure revealed normalization in all. There was immediate complete closure of the defect in two patients and six patients had trivial residual shunt (foaming through the device), which disappeared completely within 24 hr in five and at 6-month follow-up in the sixth patient. The mean fluoroscopy time was 37.1 +/- 13 min (11.7-55 min). Complications encountered included transient junctional rhythm in one patient. No blood transfusion was required. On follow-up evaluation, there has been no episode of endocarditis, thromboembolism, hemolysis, or wire disruption. we conclude that the Amplatzer MVSD occluder is a safe and effective device for closure of MVSDs up to 12 mm in diameter. Further clinical trials with this device are underway. Cathet. Cardiovasc. Intervent. 49:167-172, 2000.

Significance of proliferating cell nuclear antigen index in predicting pituitary adenoma recurrence

The recurrence rate of pituitary adenomas has been reported to be as high as 10% to 35% despite their generally benign nature. A monoclonal antibody directed against proliferating cell nuclear antigen (PCNA) was used to investigate whether the proliferative index might help to predict adenoma recurrence. This antigen is a nuclear protein identified as the auxiliary protein of deoxyribonucleic acid polymerase delta, and its gene expression correlates with cell proliferation. The authors studied 30 patients with recurrent pituitary adenomas, 32 with nonrecurrent adenomas, and seven normal pituitary tissue samples. The mean interval to recurrence ( +/- standard error of the mean) was 5.3 +/- 0.7 years. The age- and sex-matched nonrecurrent group had a mean follow-up period of 6.6 +/- 0.3 years without clinical recurrence. Mean percentages of PCNA-positive tumor nuclei in both the initial and the second surgical specimens of the recurrent adenomas (13.45% +/- 3.02% and 19.56% +/- 3.66%, respectively) were significantly higher than that of the nonrecurrent group (2.49% +/- 1.21%). In addition, recurrent tumors had a higher PCNA index than the initial tumors in the same patients. Normal anterior pituitary gland tissue had a significantly lower mean PCNA index (0.12% +/- 0.11%) than either patient group. Stepwise multivariate regression analysis indicated that factors which collectively correlated significantly with recurrence were: high PCNA index, large tumor size, extrasellar extension, and incomplete surgical excision. The PCNA nuclear count was not associated with age, sex, or hormone hypersecretion, but was higher in macro- than in microadenomas, in tumors with extrasellar extension, and in those incompletely excised. A higher PCNA index also correlated with a shorter disease-free interval. The authors conclude that evaluation of the PCNA index assists in predicting the likelihood of pituitary adenoma recurrence.

Modulation of anti-tumor immunity by the brain's reward system

Regulating immunity is a leading target for cancer therapy. Here, we show that the anti-tumor immune response can be modulated by the brain's reward system, a key circuitry in emotional processes. Activation of the reward system in tumor-bearing mice (Lewis lung carcinoma (LLC) and B16 melanoma) using chemogenetics (DREADDs), resulted in reduced tumor weight. This effect was mediated via the sympathetic nervous system (SNS), manifested by an attenuated noradrenergic input to a major immunological site, the bone marrow. Myeloid derived suppressor cells (MDSCs), which develop in the bone marrow, became less immunosuppressive following reward system activation. By depleting or adoptively transferring the MDSCs, we demonstrated that these cells are both necessary and sufficient to mediate reward system effects on tumor growth. Given the central role of the reward system in positive emotions, these findings introduce a physiological mechanism whereby the patient's psychological state can impact anti-tumor immunity and cancer progression.

Sleep fragmentation promotes NADPH oxidase 2-mediated adipose tissue inflammation leading to insulin resistance in mice

Background

Short sleep has been implicated in higher risk of obesity in humans, and is associated with insulin resistance. However, the effects of fragmented sleep (SF) rather than curtailed sleep on glucose homeostasis are unknown.

Methods

Wild type and NADPH oxidase 2 (Nox2) null male mice were subjected to SF or sleep control (SC) conditions for 3 days-3 weeks. Systemic and visceral adipose tissue (VAT) insulin sensitivity tests, glucose tolerance test, FACS and immunohistochemistry for macrophages and sub-types (M1 and M2) and Nox expression and activity were examined.

Results

Here show that SF in the absence of sleep curtailment induces time-dependent insulin resistance, in vivo and also in vitro in VAT. Oxidative stress pathways were up-regulated by SF in VAT, and were accompanied by M1 macrophage polarization. SF-induced oxidative stress, inflammation, and insulin resistance in VAT were completely abrogated in genetically altered mice lacking Nox2 activity.

Conclusions

These studies imply that SF, a frequent occurrence in many disorders and more specifically in sleep apnea, is a potent inducer of insulin resistance via activation of oxidative stress and inflammatory pathways, thereby opening the way for therapeutic strategies.

Resistance of MHC class I-deficient mice to experimental systemic lupus erythematosus

Experimental systemic lupus erythematosus (SLE) can be induced in mice by immunization with a human monoclonal antibody to DNA that bears a common idiotype (16/6Id). These mice generate antibodies to 16/6Id, antibodies to DNA, and antibodies directed against nuclear antigens. Subsequently, manifestations of SLE develop, including leukopenia, proteinuria, and immune complex deposits in the kidney. In contrast, after immunization with 16/6Id, mice lacking major histocompatibility complex (MHC) class I molecules generated antibodies to 16/6Id but did not generate antibodies to DNA or to nuclear antigen. Furthermore, they did not develop any of the above clinical manifestations. These results reveal an unexpected function of MHC class I in the induction of autoimmune SLE.

Chronic sleep fragmentation promotes obesity in young adult mice

OBJECTIVES

Short sleep confers a higher risk of obesity in humans. Restricted sleep increases appetite, promotes higher calorie intake from fat and carbohydrate sources, and induces insulin resistance. However, the effects of fragmented sleep (SF), such as occurs in sleep apnea, on body weight, metabolic rates, and adipose tissue distribution are unknown.

METHODS

C57BL/6 mice were exposed to SF for 8 weeks. Their body weight, food consumption, and metabolic expenditure were monitored over time, and their plasma leptin levels measured after exposure to SF for 1 day as well as for 2 weeks. In addition, adipose tissue distribution was assessed at the end of the SF exposure using MRI techniques.

RESULTS

Chronic SF-induced obesogenic behaviors and increased weight gain in mice by promoting increased caloric intake without changing caloric expenditure. Plasma leptin levels initially decreased and subsequently increased. Furthermore, increases in both visceral and subcutaneous adipose tissue volumes occurred.

CONCLUSIONS

These results suggest that SF, a frequent occurrence in many disorders and more specifically in sleep apnea, is a potent inducer of obesity via activation of obesogenic behaviors and possibly leptin resistance, in the absence of global changes in energy expenditure.

The acute effects of water-pipe smoking on the cardiorespiratory system

OBJECTIVE

There are limited data on the acute effects of water-pipe tobacco smoking, commonly known as water-pipe smoking (WPS), on cardiopulmonary parameters. This study evaluated the acute effects of a single 30-min session of WPS on carboxyhemoglobin (COHb) levels, pulmonary function test results, vital signs, fractional exhaled nitric oxide (Feno) levels, and exhaled breath condensate (EBC) cytokine levels in volunteers in a domestic, open-air, group smoking setting.

METHODS

This prospective study evaluated the above-noted outcome parameters before and after 30 min of WPS. The primary outcome parameter was the change in COHb levels.

RESULTS

Forty-five volunteers (30 men, 15 women), aged 32.35 ± 15.33 years, were recruited. After one session of WPS, the COHb levels rose significantly, from 1.47% ± 0.57% (median 1.4) to 9.47% ± 5.52% (median 7.4), P < .001. Systolic and diastolic BP levels significantly increased after smoking (systolic, 119.52 ± 12.07 mm Hg vs 131.98 ± 17.8 mm Hg; diastolic, 74.84 ± 7.89 mm Hg vs 82.98 ± 12.52 mm Hg, respectively; P < .001). Heart rates increased from 80.39 ± 9.92 beats/min to 95.59 ± 17.41 beats/min, P < .001; and respiratory rates increased from 14.36 ± 1.63 breaths/min to 16.68 ± 2.24 breaths/min, P < .001. There were decreases in forced expiratory flow between 25% and 75% of FVC, peak expiratory flow rate, Feno levels, percentage of eosinophils in peripheral blood, and 8-isoprostane levels in EBC.

CONCLUSIONS

This study shows that one session of WPS causes acute biologic changes that might result in marked health problems. It adds to the limited evidence that WPS is harmful and supports interventions to control the continuing global spread of WPS, especially among youth.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01157832; URL: www.clinicaltrials.gov.

COVID-19 vaccine - Long term immune decline and breakthrough infections

Background

Since the introduction of BNT162b2 mRNA COVID-19 vaccine by Pfizer in late 2020, efficacy and immunogenicity waning of COVID-19 vaccines was reported, and decision making regarding a booster remains a top priority worldwide, a decision that should be made based on breakthrough infection rate and antibody titer decline overtime.

Methods

We conducted a 5-month longitudinal prospective study involving vaccinated healthcare personnel, who were tested monthly for antibody titer, and sampled biweekly and on clinical indication for SARS-COV-2 polymerase chain reaction (PCR), to determine antibody decline and breakthrough infection.

Results

100 participants were recruited to the study. Antibody titer reached the climate after one month of the second dose of the vaccine, and declined rapidly thereafter: the median antibody levels were 895; 22,266; 9,682; 2,554 and 1,401 AU/ml in the day of the second dose, and in one month interval thereafter, respectively. In other words, four months after vaccination, the mean antibody level was 6% of the peak levels. During the study period, 4 breakthrough infections were diagnosed, 2 of which were asymptomatic, and the remaining two were mild cases; sharp elevation of antibody titer was seen after infection.

Conclusion

Antibody titer drops rapidly one month after the second dose of the vaccine. All infections within the study period were mild or asymptomatic, after which titer elevations were seen.

Chronic sleep fragmentation during the sleep period induces hypothalamic endoplasmic reticulum stress and PTP1b-mediated leptin resistance in male mice

BACKGROUND

Sleep fragmentation (SF) is highly prevalent and may constitute an important contributing factor to excessive weight gain and the metabolic syndrome. Increased endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR) leading to the attenuation of leptin receptor signaling in the hypothalamus leads to obesity and metabolic dysfunction.

METHODS

Mice were exposed to SF and sleep control (SC) for varying periods of time during which ingestive behaviors were monitored. UPR pathways and leptin receptor signaling were assessed in hypothalami. To further examine the mechanistic role of ER stress, changes in leptin receptor (ObR) signaling were also examined in wild-type mice treated with the ER chaperone tauroursodeoxycholic acid (TUDCA), as well as in CHOP-/+ transgenic mice.

RESULTS

Fragmented sleep in male mice induced increased food intake starting day 3 and thereafter, which was preceded by increases in ER stress and activation of all three UPR pathways in the hypothalamus. Although ObR expression was unchanged, signal transducer and activator of transcription 3 (STAT3) phosphorylation was decreased, suggesting reduced ObR signaling. Unchanged suppressor of cytokine signaling-3 (SOCS3) expression and increases in protein-tyrosine phosphatase 1B (PTP1B) expression and activity emerged with SF, along with reduced p-STAT3 responses to exogenous leptin. SF-induced effects were reversed following TUDCA treatment and were absent in CHOP -/+ mice.

CONCLUSIONS

SF induces hyperphagic behaviors and reduced leptin signaling in hypothalamus that are mediated by activation of ER stress, and ultimately lead to increased PTP1B activity. ER stress pathways are therefore potentially implicated in SF-induced weight gain and metabolic dysfunction, and may represent a viable therapeutic target.

Sympathetic and catecholaminergic alterations in sleep apnea with particular emphasis on children

Sleep is involved in the regulation of major organ functions in the human body, and disruption of sleep potentially can elicit organ dysfunction. Obstructive sleep apnea (OSA) is the most prevalent sleep disorder of breathing in adults and children, and its manifestations reflect the interactions between intermittent hypoxia, intermittent hypercapnia, increased intra-thoracic pressure swings, and sleep fragmentation, as elicited by the episodic changes in upper airway resistance during sleep. The sympathetic nervous system is an important modulator of the cardiovascular, immune, endocrine and metabolic systems, and alterations in autonomic activity may lead to metabolic imbalance and organ dysfunction. Here we review how OSA and its constitutive components can lead to perturbation of the autonomic nervous system in general, and to altered regulation of catecholamines, both of which then playing an important role in some of the mechanisms underlying OSA-induced morbidities.

Inflammatory pathways in children with insufficient or disordered sleep

Sleep is not only an essential physiological function, but also serves important roles in promoting growth, maturation, and overall health of children and adolescents. There is increasing interest regarding the impact of sleep and its disorders on the regulation of inflammatory processes and end-organ morbidities, particularly in the context of metabolic and cardiovascular diseases (CVD) and their complications. Obstructive sleep apnea syndrome (OSAS) is an increasingly common health problem in children, and in the last decade, the emergence of increasing obesity rates has further led to remarkable increases in the prevalence of OSAS, along with more prominent neurocognitive, behavioral, cardiovascular and metabolic morbidities. Although the underlying mechanisms leading to OSAS-induced morbidities are likely multi-factorial, and remain to be fully elucidated, activation of inflammatory pathways by OSAS has emerged as an important pathophysiological component of the end-organ injury associated with this disorder. To this effect, it would appear that OSAS could be viewed as a chronic, low-grade inflammatory disorder. Furthermore, the concurrent presence of obesity and OSAS poses a theoretically increased risk of OSAS-related complications. In this review, we will critically review the current state of research regarding the impact of insufficient and disrupted sleep and OSAS on the immune processes and inflammatory pathways that underlie childhood OSAS as a distinctive systemic inflammatory condition in children, and will explore potential interactions between OSAS and obesity.

Obesity and Altered Sleep: A Pathway to Metabolic Derangements in Children?

Obstructive sleep apnea (OSA) is a frequent disorder in children and is primarily associated with adenotonsillar hypertrophy. The prominent increases in childhood overweight and obesity rates in the world even among youngest of children have translated into parallel increases in the prevalence of OSA, and such trends are undoubtedly associated with deleterious global health outcomes and life expectancy. Even an obesity phenotype in childhood OSA, more close to the adult type, has been recently proposed. Reciprocal interactions between sleep in general, OSA, obesity, and disruptions of metabolic homeostasis have emerged in recent years. These associations have suggested the a priori involvement of complex sets of metabolic and inflammatory pathways, all of which may underlie an increased risk for increased orexigenic behaviors and dysfunctional satiety, hyperlipidemia, and insulin resistance that ultimately favor the emergence of metabolic syndrome. Here, we review some of the critical evidence supporting the proposed associations between sleep disruption and the metabolism-obesity complex. In addition, we describe the more recent evidence linking the potential interactive roles of OSA and obesity on metabolic phenotype.

Biomarkers in chronic graft-versus-host disease: quo vadis?

Biomarkers are increasingly used for diagnosis and treatment of transplant-related complications including the first biomarker-driven interventional trials of acute graft-versus-host disease (GvHD). In contrast, the development of biomarkers of chronic GvHD (cGvHD) has lagged behind due to a broader variety of manifestations, overlap with acute GvHD, a greater variation in time to onset and maximum severity, and lack of sufficient patient numbers within prospective trials. An international workshop organized by a North-American and European consortium was held in Marseille in March 2017 with the goal to discuss strategies for future biomarker development to guide cGvHD therapy. As a result of this meeting, two areas were prioritized: the development of prognostic biomarkers for subsequent onset of moderate/severe cGvHD, and in parallel, the development of qualified clinical-grade assays for biomarker quantification. The most promising prognostic serum biomarkers are CXCL9, ST2, matrix metalloproteinase-3, osteopontin, CXCL10, CXCL11, and CD163. Urine-proteomics and cellular subsets (CD4+ T-cell subsets, NK cell subsets, and CD19+CD21low B cells) represent additional potential prognostic biomarkers of cGvHD. A joint effort is required to verify the results of numerous exploratory trials before any of the potential candidates is ready for validation and subsequent clinical application.

Prostate cancer cell growth inhibition by tamoxifen is associated with inhibition of protein kinase C and induction of p21(waf1/cip1)

BACKGROUND

Inhibition of protein kinase C (PKC) and modulation of transforming growth factor-beta (TGF-beta) are both associated with tamoxifen treatment, and both appear to be important in the regulation of prostate cancer cell growth. Investigations were performed which sought to measure the efficacy, and to elucidate the mechanism of growth inhibition by tamoxifen, in hormone-refractory prostate cancer.

METHODS

Growth assays were performed on PC3, PC3-M, and DU145 prostate cancer cells. TGF-beta was measured by ELISA; p21(waf1/cip1) and retinoblastoma (Rb) protein levels were measured by Western blot; PKC activity was measured by kinase assay; and effects upon cell cycle were measured by flow cytometric analysis.

RESULTS

IC50s for growth inhibition ranged from 5.5-10 microM, and were not affected by estrogen. Tamoxifen-mediated growth inhibition was not associated with induction of TGF-beta. However, tamoxifen treatment was associated with inhibition of PKC, which was followed by induction of p21(waf1/cip1), Rb dephosphorylation, and G1/S phase cell cycle arrest. Similar effects were observed with the known PKC inhibitor, Ro31-8220.

CONCLUSIONS

These data suggest that micromolar concentrations of tamoxifen inhibit prostate cancer cell growth by inhibition of PKC, resulting in induction of the p21(waf1/cip1) protein.

Vitamins A and E and pulmonary exacerbations in patients with cystic fibrosis

BACKGROUND

Increased levels of oxidative stress result in pulmonary damage contributing to the development of chronic lung disease in cystic fibrosis (CF). The aim of this study was to investigate the longitudinal effect of serum vitamin A and E levels on the incidence of pulmonary exacerbations in pancreatic insufficient (PI) and pancreatic sufficient (PS) patients with CF.

MATERIALS AND METHODS

Patient records were retrospectively examined over a 3-year period and serum vitamin A and E levels were retrieved. Subsequently, levels of vitamin A and E were prospectively measured over a 2-year period at the onset of intravenous antibiotic therapy for acute exacerbation and at the first recovery visit.

RESULTS

Retrospectively, 597 pulmonary exacerbations were identified in 102 patients, 74 PI and 28 PS, with a mean age of 11.1 +/- 6.4 years (range, 1.5-27 y). An increased number of exacerbations was directly correlated with lower vitamin A and E levels, even within the normal range. Prospectively, 62 exacerbations were analyzed (43 PI patients and 19 PS patients). At onset of exacerbation, vitamin A and E levels were reduced in the PI patients (P < 0.001; P < 0.001) and the PS patients (P < 0.005; P < 0.07).

CONCLUSIONS

Reduced serum levels of vitamin A and E even in the normal range are associated with an increased rate of pulmonary exacerbations in CF. Further studies are required to confirm the necessity of supplementation of vitamins A and E to PS patients.

The effect of vitamin D on airway reactivity and inflammation in asthmatic children: A double-blind placebo-controlled trial

BACKGROUND

Cross-sectional studies have reported an association of vitamin D deficiency with increased asthma prevalence and severity, and with allergies. The effect of vitamin D as sole therapy on airway hyper-reactivity (AHR) and airway inflammation has not been reported.

AIM

To evaluate the effect of vitamin D therapy on AHR as assessed by methacholine concentration, causing a 20% reduction in FEV1 (PC20 -FEV1 ) and fractional exhaled nitric oxide (FeNO), systemic markers of allergy and inflammation, and exhaled breath condensate cytokines.

PATIENTS AND METHODS

Children aged 6-18 years with a clinical diagnosis of mild asthma currently not receiving anti-inflammatory therapy and with low vitamin D levels were included in this randomized, double-blind, placebo-controlled study assessing the effect of 6 weeks of treatment with oral vitamin D 14,000 units once weekly or placebo.

RESULTS

Of the 39 patients included, 20 received vitamin D treatment and 19 received a placebo. Vitamin D replacement resulted in a significant increase in vitamin levels, which remained unchanged in the placebo group (P < 0.0001). There was no change in IgE, eosinophil count, high sensitivity C-reactive protein, FeNO levels or PC20 -FEV1 following treatment. Similar values of exhaled breath condensate cytokines (IL4, IL5, IL10, IL17, and γ interferon) were observed in both groups.

CONCLUSIONS

In our small group of children with mild asthma, no difference could be demonstrated between the effect of vitamin D and placebo, despite significant increases in vitamin D blood levels. Larger interventional studies are needed to fully explore the possible effect of vitamin D in asthma.

Sleep fragmentation during late gestation induces metabolic perturbations and epigenetic changes in adiponectin gene expression in male adult offspring mice

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.

Chemoreceptors, baroreceptors, and autonomic deregulation in children with obstructive sleep apnea

Obstructive sleep apnea (OSA) is highly prevalent sleep disorder of breathing in both adults and children that is fraught with substantial cardiovascular morbidities, the latter being attributable to a complex interplay between intermittent hypoxia (IH), episodic hypercapnia, recurrent large intra-thoracic pressure swings, and sleep disruption. Alterations in autonomic nervous system function could underlie the perturbations in cardiovascular, neurocognitive, immune, endocrine and metabolic functions that affect many of the patients suffering from OSA. Although these issues have received substantial attention in adults, the same has thus far failed to occur in children, creating a quasi misperception that children are protected. Here, we provide a critical overview of the evidence supporting the presence of autonomic nervous system (ANS) perturbations in children with OSA, draw some parallel assessments to known mechanisms in rodents and adult humans, particularly, peripheral and central chemoreceptor and baroreceptor pathways, and suggest future research directions.

The effect of montelukast on bronchial hyperreactivity in preschool children

INTRODUCTION

The effect of montelukast therapy on bronchial hyperreactivity (BHR) as measured by the methacholine challenge test in preschool children has not yet been reported.

OBJECTIVE

To determine the effect of montelukast (4 mg/d) on BHR as evaluated by a provocative concentration of a substance causing a 20% fall in FEV(1) (PC(20)) values in preschool asthmatic children.

PATIENTS

A total of 26 preschool children (8 girls) aged 3.3 to 6.0 years (mean [+/- SD] age, 4.7 +/- 0.8 years) with mild asthma.

DESIGN

Double-blind randomized, placebo controlled, crossover study. Each child received 4 weeks of treatment with 4 mg of either montelukast or placebo separated by a 2-week washout period. Primary outcomes were PC(20) values and the stage number (triple dose) at which FEV(1) values dropped by 20%(.) Post-montelukast therapy PC(20) was compared to those for the post-placebo period.

RESULTS

Following 4 weeks of montelukast treatment, the mean PC(20) was 4.79 +/- 4.69 mg/mL, while after 4 weeks of placebo the mean PC(20) was 2.07 +/- 2.37 mg/mL (p = 0.001). The montelukast/placebo ratio for PC(20) was 2.56 with a 95% confidence interval (CI) of 1.71 to 3.99. The median difference in stage was one triple dose with a 95% CI of 0.5 to 1.5.

CONCLUSIONS

Four weeks of treatment with montelukast resulted in a decreased BHR compared with placebo.

Optogenetic activation of local colonic sympathetic innervations attenuates colitis by limiting immune cell extravasation

The sympathetic nervous system is composed of an endocrine arm, regulating blood adrenaline and noradrenaline, and a local arm, a network of fibers innervating immune organs. Here, we investigated the impact of the local arm of the SNS in an inflammatory response in the colon. Intra-rectal insertion of an optogenetic probe in mice engineered to express channelrhodopsin-2 in tyrosine hydroxylase cells activated colonic sympathetic fibers. In contrast to systemic application of noradrenaline, local activation of sympathetic fibers attenuated experimental colitis and reduced immune cell abundance. Gene expression profiling showed decreased endothelial expression of the adhesion molecule MAdCAM-1 upon optogenetic stimulation; this decrease was sensitive to adrenergic blockers and 6-hydroxydopamine. Antibody blockade of MAdCAM-1 abrogated the optogenetic effect on immune cell extravasation into the colon and the pathology. Thus, sympathetic fibers control colonic inflammation by regulating immune cell extravasation from circulation, a mechanism likely relevant in multiple organs.