Exhaled nitric oxide and inducible nitric oxide synthase gene polymorphism in Japanese asthmatics

V Brazilian Consensus on Rhinitis - 2024

Since we published the "IV Brazilian Consensus on Rhinitis", in2017, several advances have been achieved and have enabled a further understanding of the different aspects of "Rhinitis". This new guideline, developed jointly by ASBAI, SBP and SBORL, represents a relevant milestone in the updated and integrated management of the different forms of the disease, and it aims to unify evidence-based approaches to improve the diagnosis and treatment of this common and often underestimated condition. The document covers a wide range of topics, including clear definitions of the different phenotypes and endotypes of rhinitis, risk factors, updated diagnostic criteria, and recommended methods for clinical and laboratory investigation. We stress the importance of detailed clinical history and objective assessment, as well as tools for control and assessing severity tools an accurate diagnostic approach to the disease. Regarding treatment, it emphasizes the treatment customization, considering the severity of symptoms, the presence of comorbidities and the impact on the patient's quality of life. We discuss different drug treatment, in addition to non-pharmacological measures, such as environmental control and specific immunotherapy; and the possible role of immunobiological agents. Furthermore, the consensus addresses issues related to patient education, prevention and management of special situations, such as rhinitis in children, in pregnant women and in the elderly. In short, the "V Brazilian Consensus on Rhinitis" represents a comprehensive and updated guide for healthcare professionals involved in the diagnosis and management of rhinitis, aiming to improve patients' quality of life through an integrated and evidence-based approach.

SNPs inFAM13AandIL2RBgenes are associated with FeNO in adult subjects with asthma

Nitric oxide has different roles in asthma as both an endogenous modulator of airway function and a pro-inflammatory mediator. Fractional exhaled nitric oxide (FeNO) is a reliable, quantitative, non-invasive, simple, and safe biomarker for assessing airways inflammation in asthma. Previous genome-wide and genetic association studies have shown that different genes and single nucleotide polymorphisms (SNPs) are linked to FeNO. We aimed at identifying SNPs in candidate genes or gene regions that are associated with FeNO in asthma. We evaluated 264 asthma cases (median age 42.8 years, female 47.7%) who had been identified in the general adult population within the Gene Environment Interactions in Respiratory Diseases survey in Verona (Italy; 2008-2010). Two hundred and twenty-one tag-SNPs, which are representative of 50 candidate genes, were genotyped by a custom GoldenGate Genotyping Assay. A two-step association analysis was performed without assuming ana priorigenetic model: step (1) a machine learning technique [gradient boosting machine (GBM)] was used to select the 15 SNPs with the highest variable importance measure; step (2) the GBM-selected SNPs were jointly tested in a linear regression model with natural log-transformed FeNO as the normally distributed outcome and with age, sex, and the SNPs as covariates. We replicated our results within an independent sample of 296 patients from the European Community Respiratory Health Survey III. We found that SNP rs987314 in family with sequence similarity 13 member A (FAM13A) and SNP rs3218258 in interleukin 2 receptor subunit beta (IL2RB) gene regions are significantly associated with FeNO in adult subjects with asthma. These genes are involved in different mechanisms that affect smooth muscle constriction and endothelial barrier function responses (FAM13A), or in immune response processes (IL2RB). Our findings contribute to the current knowledge on FeNO in asthma by identifying two novel SNPs associated with this biomarker of airways inflammation.

Immunologic, genetic, and ecological interplay of factors involved in allergic diseases

An allergic or type I hypersensitivity reaction involves a misdirected immune overreaction to innocuous environmental and dietary antigens called allergens. The genetic predisposition to allergic disease, referred to as atopy, can be expressed as a variety of manifestations-e.g., allergic rhinitis, allergic conjunctivitis, atopic dermatitis, allergic asthma, anaphylaxis. Globally, allergic diseases are one the most common types of chronic conditions. Several factors have been identified to contribute to the pathogenesis and progression of the disease, leading to distinctively variable clinical symptoms. The factors which can attenuate or exacerbate allergic reactions can range from genetic heterozygosity, the prominence of various comorbid infections, and other factors such as pollution, climate, and interactions with other organisms and organism-derived products, and the surrounding environment. As a result, the effective prevention and control of allergies remains to be one of the most prominent public health problems. Therefore, to contextualize the current knowledge about allergic reactions, this review paper attempts to synthesize different aspects of an allergic response to describe its significance in the global health scheme. Specifically, the review shall characterize the biomolecular mechanisms of the pathophysiology of the disease based on underlying disease theories and current findings on ecologic interactions and describe prevention and control strategies being utilized. An integrated perspective that considers the underlying genetic, immunologic, and ecologic aspects of the disease would enable the development of more effective and targeted diagnostic tools and therapeutic strategies for the management and control of allergic diseases.

A nitric oxide responsive AIE probe for detecting the progression of osteoarthritis

Nitric oxide (NO) is reported to be elevated in osteoarthritis (OA) both in vitro and in vivo and may be adopted to develop fluorescent probes for detecting the progression of OA. Here we report a nitric oxide responsive aggregation induced emission (AIE) probe TPE-2NHCOCH2CH2-(PEG)24-NH-Diacerein, which is derived from tetraphenylethene (TPE) modified with the hydrophilic group long poly(ethylene glycol) chain and an anti-inflammatory drug diacerein. o-Phenylenediamine within its structure can react with NO to form benzotriazole and emit fluorescence. The results show that the NO-responsive AIE probe can smartly monitor the progression of OA with the change of fluorescence intensity in vitro and in vivo. This study may provide a new development direction for early OA monitoring in clinics.

Inducible Nitric Oxide Synthase iNOS-954-G>C and Ex16+14-C>T Gene Polymorphisms and Susceptibility to Vitiligo in the Saudi Population

Objective

Vitiligo is an acquired pigmentary skin disorder with regional disappearance of melanocytes. Multigenic inheritance has been proposed in the pathogenesis of vitiligo. The present study aimed to investigate the possible association of inducible nitric oxide synthase polymorphisms iNOS-954-G/C (rs1800482 G>C) and iNOS-Ex16+14-C/T (rs2297518 C>T) with vitiligo in the Saudi population, if any.

Methods

We included 120 vitiligo cases and an equal number of age matched healthy controls. Polymerase chain reaction with restriction fragment length polymorphism method was used for the analysis of genetic polymorphisms.

Results

The heterozygous (GC), (GC + CC) combined genotype and variant allele; C allele of rs1800482 G>C were associated significantly (p < 0.005, after Bonferroni correction) with increased risk of vitiligo (OR = 3.46, 95% CI = 1.99–6.01, p = 0.001), (OR = 3.30, 95% CI= 1.93–5.65, p = 0.001) and (OR = 1.94, 95% CI = 1.31–2.87, p = 0.001) respectively. When GC genotype of rs1800482 G>C was co-inherited with common genotype (CC) and heterozygous genotype (CT) of rs2297518 C>T, the risk of vitiligo was significantly increased ((OR = 4.51, 95% CI = 2.18–9.33, p = 0.001) and (OR = 3.60, 95% CI = 1.61–8.01, p = 0.001)) respectively. None of the rs1800482 G>C and rs2297518 C>T genotypes and alleles have been associated with non-segmental vitiligo in terms of gender, age of onset, and types of vitiligo.

Conclusion

The heterozygous (GC), (GC+CC) combined genotype and variants allele; C allele of rs1800482 G>C, may cause overproduction of NO, which has been linked to melanocyte loss by increasing oxidative stress and decreasing melanocyte adhesion to the extracellular matrix components, and thus could be an associative risk factor for vitiligo.

Nitric oxide synthase-2 (CCTTT)n polymorphism is associated with local gene expression and clinical manifestations in patients with chronic rhinosinusitis

Introduction

Nitric oxide (NO) is synthesized through NO synthase (NOS). The proximal NOS2 gene promoter contains the pentanucleotide CCTTT repeat polymorphism. We examined whether CCTTT repeats are associated with NOS2 expression in the sinonasal tissues and clinical manifestations in patients with chronic rhinosinusitis.

Methods

Mucosal specimens were obtained from the ethmoid sinus and inferior turbinate of 30 eosinophilic chronic rhinosinusitis (ECRS) and 28 non-ECRS patients. CCTTT repeats were classified into short alleles (S), with less than or equal to 14, and long alleles (L), with more than 14. The subjects were classified into the L/S + L/L and S/S groups.

Results

In ECRS, the NOS2 mRNA levels of the ethmoid sinus mucosa were significantly higher in the L/S + L/L group than in the S/S group (median, 1.66 and 0.77, respectively). On the ther hand, ECRS patients showed no significant difference in the NOS2 mRNA level of the inferior turbinate between the L/S + L/L group and the S/S group (median, 0.63 and 0.88, respectively). In ECRS, preoperative SNOT-22 were significantly higher in the L/S + L/L group than in the S/S group, whereas the former group showed a lower postoperative recurrence risk.

Conclusion

CCTTT repeat polymorphism in the NOS2 promotor gene may be a useful indicator to evaluate ECRS severity and prognosis.

Nitric Oxide Synthase 2 Promoter Polymorphism Is a Risk Factor for Allergic Asthma in Children

Background and Objectives: In paediatric population, atopic asthma is associated with increased eosinophil counts in patients, that correlate with the airway inflammation measured by the concentration of nitric oxide in exhaled air (FeNO). As the FeNO level is a biomarker of atopic asthma, we assumed that polymorphisms in nitric synthases genes may represent a risk factor for asthma development. The purpose of this study was to analyse the association of NOS genetic variants with childhood asthma in the Polish population. Materials and methods: In study we included 443 children—220 patients diagnosed with atopic asthma and 223 healthy control subjects. We have genotyped 4 single nucleotide polymorphisms (SNP) from 3 genes involved in the nitric oxide synthesis (NOS1, NOS2 and NOS3). All analyses were performed using polymerase chain reaction with restriction fragments length polymorphism (PCR-RFLP). Results: We observed significant differences between cases and controls in SNP rs10459953 in NOS2 gene, considering both genotypes (p = 0.001) and alleles (p = 0.0006). The other analyzed polymorphisms did not show association with disease. Conclusions: According to our results, 5′UTR variant within NOS2 isoform may have an impact of asthma susceptibility in the population of Polish children. Further functional studies are required to understand the role of iNOS polymorphism in NOS2 translation and to consider it as a novel risk factor in childhood asthma. The next step would be to apply this knowledge to improve diagnosis and develop novel personalized asthma therapies.

Nasal nitric oxide testing for allergic rhinitis patients: Systematic review and meta-analysis

BACKGROUND

Nasal nitric oxide (nNO) levels in allergic rhinitis (AR), healthy people or nonallergic rhinitis (NAR) have shown contradicting results in previous studies. By meta-analysis, we reviewed studies that measured nNO in AR patients to assess nNO's ability to discriminate AR from healthy people or NAR.

METHODS

We systematically searched PubMed, Cochrane, Embase, Ovid, Web of Science, Wanfang Data, CNKI until December 15, 2020. Differences were expressed as standardized mean differences (SMD) with 95% confidence interval (CI), by random-effects method.

RESULTS

A total of 10 original studies with 561 AR patients, 327 healthy controls, 123 NAR patients were included in the narrative synthesis and 9 studies in the meta-analysis. nNO in AR was significantly increased compared with healthy controls (SMD: 0.989; 95% CI: 0.402, 1.576; p = .001) or NAR (SMD: 0.680; 95% CI: 0.101, 1.259; p = 0.021). However, subgroup analysis based on measuring process and patient characteristics showed that no significant differences were detected in nNO between AR patients with nasal polyps or sinusitis or marked ostial obstruction and healthy controls.

CONCLUSIONS

nNO is a potential indicator for recognizing AR. Nasal polyps, sinusitis and marked ostial obstruction should be considered before nNO is applied to detect AR.

Exhaled nitric oxide in pediatric patients with respiratory disease

Measurement of nitric oxide (NO) levels in exhaled air from the upper and lower airways is currently used as a non-invasive marker of inflammation in respiratory diseases. Assessment of NO exhaled from the lower air respiratory tract is considered to be a quick method for confirmation and control of asthma in patients as well as an estimation of treatment efficiency. The main aim of this study was to determine differences between levels of exhaled nitric oxide (fractional exhaled NO; FeNO) in patients with respiratory disease as measured by an electrochemical analyzer. Measurements were taken in 352 pediatric patients aged 4-17 with cystic fibrosis (CF) (n = 43), asthma (n = 69), allergic rhinitis (AR) (n = 70), asthma and AR (n = 128) and non-diseased children (n = 42) recruited from the Allergology Outpatient Department, Provincial Hospital No 2, Rzeszów. The second objective of this study was to assess any correlations between FeNO and clinical parameters of patients. The level of FeNO in patients with CF was normal when compared with control subjects (10.8 ± 2.9 versus 11.4 ± 6 ppb). We found significantly higher FeNO in patients with asthma (26.6 ± 15.3 ppb, p < 0.001), AR (18.4 ± 9.6 ppb, p < 0.01) as well as in patients with both asthma and AR (43.3 ± 31.1 ppb, p < 0.001) when compared to healthy children. Statistical analysis revealed a positive correlation between FeNO and age, height and weight of control subjects, and height in children with AR. FeNO was independent of sex, BMI, spirometry and blood results as well as the type of residence in control children and subjects with CF, asthma, AR and combined asthma and AR. In conclusion, we found normal levels of FeNO in children with CF and elevated levels in patients with asthma, AR and combined asthma and AR as compared to control subjects. Due to conflicting data, there is still a need for additional research, especially related to regarding factors that affect FeNO levels in respiratory disease.

Nitric Oxide Nanosensors for Predicting the Development of Osteoarthritis in Rat Model

Osteoarthritis (OA) is a chronic arthritic disease that causes the overproduction of inflammatory factors such as nitric oxide (NO). This study develops a NO nanosensor to predict the OA development. The nanosensor is synthesized by encapsulating the NO sensing molecules (i.e., 4-amino-5-methylamino-2',7'-difluorofluorescein Diaminofluorescein-FM (DAF-FM)) within the biodegradable poly(lactic-co-glycolic acid) nanoparticles. In vitro, the nanosensor allows the monitoring of the NO release in interleukin-1β-stimulated chondrocytes and the alleviated effect of N^G-monomethyl-l-arginine (a NO inhibitor) and andrographolide (an anti-inflammatory agent). In the rat OA model, it permits the quantification of NO level in joint fluid. The proposed NO nanosensor may facilitate a noninvasive and real-time evaluation of the OA development.

Inducible nitric oxide synthase gene polymorphisms are associated with a risk of nephritis in Henoch-Schönlein purpura children

Henoch-Schönlein purpura (HSP) is the most common form of systemic small-vessel vasculitis in children, and HSP nephritis (HSPN) is a major complication of HSP and is the primary cause of morbidity and mortality. Previous studies have suggested that inducible nitric oxide synthase (iNOS) may play an important role in the pathogenesis of HSP. In this study, we performed a detailed analysis to investigate the potential association between iNOS polymorphisms and the risk of HSP and the tendency for children with HSP to develop HSPN in a Chinese Han population. A promoter pentanucleotide repeat (CCTTT)n and 10 functional single-nucleotide polymorphisms (SNPs) from 532 healthy controls and 513 children with HSP were genotyped using the MassARRAY system and GeneScan. The results suggested that the allelic and genotypic frequencies of the rs3729508 polymorphism were nominally associated with susceptibility to HSP. In addition, there was a significant difference in the allelic distribution of the (CCTTT)12 repeats and rs2297518 between the HSP children with and without nephritis; the HSP children with nephritis exhibited a significantly higher frequency of the (CCTTT)12 repeats and A allele of rs2297518 than the HSP children without nephritis (P _FDR = 0.033, OR = 1.624, 95% CI = 1.177-2.241 and P _FDR = 0.030, OR = 1.660, 95% CI = 1.187-2.321, respectively).

CONCLUSION

Our results support that iNOS polymorphisms are associated with the risk of HSP and may strongly contribute to the genetic basis of individual differences in the progression to nephritis among children with HSP in the Chinese Han population. What is Known: • The etiology of HSP is unknown, but the genetic factors may play an important role in the pathogenesis of HSP. • iNOS could contribute to the development and clinical manifestations of HSP, and this has not been studied extensively so far. What is New: • Our results support that iNOS polymorphisms not only are associated with HSP risk but also strongly contribute to the genetic basis of individual differences in the progression of HSP to nephritis among Chinese Han children.

Fraction of exhaled nitric oxide as a predictor in juvenile idiopathic arthritis progression

In this study, the relation between the nitric oxide (NO) levels in the serum and fraction of exhaled nitric oxide (F_ENO) in children with juvenile idiopathic arthritis (JIA) and the activation criteria of the disease has been investigated. The study group consisted of 35 JIA-diagnosed patients and 18 healthy children. According to the clinical and laboratory findings, the patients with JIA were divided into two groups, active (group I) and in remission (group II). The healthy children were classified as group III. The activation criteria of the disease were determined for each patient. The serum NO level and F_ENO level were measured in all the patients. In the group with JIA, correlation was detected between F_ENO level and number of involved joints and number of joints with limited motion. In addition, correlation was determined between the F_ENO level and number of involved joints in group I and the serum NO level and activity score in group II. However, it was seen that there is no statistical difference in the serum NO level and F_ENO level of the patients with JIA and the control group and groups I and II. This study demonstrated the correlation between F_ENO level and number of involved joints and number of joints with limited motion in patients with JIA. Our results matter in terms of F_ENO being a noninvasive laboratory marker in following the progression of the disease.