ADRB2 Polymorphism and Salbutamol Responsiveness in Northern Indian Children with Mild to Moderate Exacerbation of Asthma

Regulation of T Helper Cell Type 2 Immune Response by Controlling Beta-2 Adrenergic Receptor in Dendritic Cells of Patients with Allergic Rhinitis

INTRODUCTION

Allergic diseases are mediated by T helper cell type 2 (Th2) cells, which are differentiated by dendritic cells (DCs). Recently, it was reported that cAMP concentration in DCs is important for inducing allergic responses. However, the regulatory function of cAMP in DCs in Th2 immune responses is unclear. It was hypothesized that the regulation of G protein-coupled receptors (GPCRs) to increase cAMP levels in DCs would reduce Th2 immune responses.

METHODS

Human DCs from patients with allergic rhinitis (AR) and from healthy controls were subjected to next-generation sequencing (NGS) to identify potential GPCR. To investigate the functions of GPCR agonists, the in vitro co-culture experiment that THP-1 cells were differentiated into DCs and cultured with human CD4+ T-cells and an AR animal in vivo model were used.

RESULTS

Among the GPCRs, the beta-2 adrenergic receptor (ADRB2) of allergic DCs was significantly increased by NGS analysis. The expression of ADRB2 was also increased in Der p 1-treated DCs, which was reduced by treatment with the ADRB2 agonist salbutamol. Salbutamol treatment induced cAMP production in THP-1 derived DCs. In an in vitro co-culture experiment, salbutamol-treated DCs reduced the secretion of Th2 cytokine. In an in vivo AR animal experiment, salbutamol-administered mice showed reduced allergic behavior and Th2 cytokine expression in the nasal mucosa.

CONCLUSIONS

The regulation of ADRB2 with salbutamol alleviated the allergic response in vitro DC-T cell co-culture and in vivo AR animal models, suggesting that ADRB2 is a therapeutic target for AR and that ADRB2 agonists may be a promising medication for AR.

Association between ADRB2 regulatory region polymorphisms and susceptibility to childhood asthma

OBJECTIVES

To study the association of β2-drenergic receptor (ADRB2) regulatory region single nucleotides polymorphism (SNP)/haplotypes at rs11168070, rs17108803, rs2053044, rs12654778, rs11959427, and rs2895795 loci with childhood asthma.

METHODS

A total of 143 children with asthma who attended the hospital from October 2016 to October 2020 were enrolled as the asthma group, among whom 61 children had mild symptoms (mild group) and 82 children had moderate-to-severe symptoms (moderate-to-severe group). A total of 137 healthy children were enrolled as the control group. Peripheral venous blood samples were collected from the two groups. The SNaPshot SNP technique was used to analyze the SNP and haplotypes of the ADRB2 regulatory region at rs11168070, rs17108803, rs2053044, rs12654778, rs11959427, and rs2895795 loci in all children. The asthma group and the control group were compared in terms of the association of ADRB2 regulatory region SNP and haplotypes at the above six loci with susceptibility to asthma and severity of asthma.

RESULTS

Polymorphisms were observed in the ADRB2 regulation region at the above six loci in both the asthma group and the control group, with significant differences between the two groups in the distribution of genotype and allele frequencies at rs2895795 (-1429T /A), rs2053044(-1023G/A), and rs12654778 (-654G/A) loci (P<0.05). Linkage disequilibrium of SNP was observed at the six loci of the ADRB2 regulatory region.The haplotypes of TATGCT, TATGGC, and AGTGCT were associated with susceptibility to childhood asthma, among which TATGCT and TATGGC were risk factors for childhood asthma (OR=1.792 and 1.946 respectively, P<0.05), while AGTGCT was a protective factor (OR=0.523, P<0.05).

CONCLUSIONS

SNP/haplotype of the ADRB2 regulatory region is associated with the susceptibility to childhood asthma. The haplotypes of TATGCT and TATGGC formed by such SNP/haplotype are risk factors for childhood asthma, while AGTGCT is a protective factor.

Genetic Determinants of Poor Response to Treatment in Severe Asthma

Severe asthma is a multifactorial disorder with marked phenotypic heterogeneity and complex interactions between genetics and environmental risk factors, which could, at least in part, explain why during standard pharmacologic treatment, many patients remain poorly controlled and at an increased risk of airway remodeling and disease progression. The concept of “precision medicine” to better suit individual unique needs is an emerging trend in the management of chronic respiratory diseases. Over the past few years, Genome-Wide Association Studies (GWAS) have revealed novel pharmacogenetic variants related to responses to inhaled corticosteroids and the clinical efficacy of bronchodilators. Optimal clinical response to treatment may vary between racial/ethnic groups or individuals due to genetic differences. It is also plausible to assume that epigenetic factors play a key role in the modulation of gene expression patterns and inflammatory cytokines. Remarkably, specific genetic variants related to treatment effectiveness may indicate promising pathways for novel therapies in severe asthma. In this review, we provide a concise update of genetic determinants of poor response to treatment in severe asthma and future directions in the field.

A meta-analysis of the influence of ADRB2 genetic polymorphisms on albuterol (salbutamol) therapy in patients with asthma

AIMS

The associations of 2 nonsynonymous single nucleotide polymorphisms (Arg16Gly and Gln27Glu) in the adrenoceptor β2 (ADRB2) gene with response after albuterol use are conflicting. We conducted a meta-analysis to examine the cumulative evidence of the effects of these 2 variants on percent forced expiratory volume in 1 second (FEV1.0%) after albuterol use in asthma patients.

METHODS

We conducted a comprehensive literature search using MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials to identify studies examining the association between ADRB2 Arg16Gly and Gln27Glu and FEV1.0% shortly after albuterol administration. The individual study results were combined with weights based on the inverse variance method. This systematic review was registered in the PROSPERO (registration number: CRD42019074554).

RESULTS

Among 273 initial studies identified, 7 studies met the inclusion criteria for quantitative evaluation. Results of the overall meta-analysis indicated no statistically significant mean difference of FEV1.0% between genotypes of Arg16Gly and Gln27Glu. In subgroup analyses, significant associations were found for Arg16Gly GG (vs AA) among studies where no methacholine bronchoconstriction was conducted (mean difference, -3.92; 95% confidence interval, -7.29 to -0.54; I2 = 0%), and for Arg16Gly GG (vs GA) among studies that included patients with no comorbidities (mean difference, -1.93; 95% confidence interval, -3.77 to -0.10; I2 = 0%).

CONCLUSION

Synthesis of the studies to date shows weak evidence for an association between ADRB2 Arg16Gly and Gln27Glu and FEV1.0% after albuterol use, results of which underscore significant heterogeneity across studies and the need for careful design and sample size considerations.

Association of β2-adrenergic receptor gene polymorphisms (rs1042713, rs1042714, rs1042711) with asthma risk: a systematic review and updated meta-analysis

Background

The published data on the association between β2-adrenergic receptor gene polymorphisms and asthma susceptibility are inconclusive. To derive a more precise estimation of this association, a meta-analysis was performed.

Methods

A literature search was conducted in PubMed, Web of Science, EMBASE, Wanfang, and the China National Knowledge Infrastructure (CNKI) databases to identify eligible studies. The pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were used to calculate the strength of the association. A sensitivity analysis was performed to evaluate the influence of individual studies on the overall effect estimates, and funnel plots and Egger’s tests were used for indications of publication bias.

Results

Seventy three studies with three single nucleotide polymorphisms (SNP) (rs1042713, c.G46A, p.Gly16Arg; rs1042714, c.G79C, p.Gln27Glu; rs1042711, c.T-47C, p.Cys19Arg) were finally identified. For the rs1042713 polymorphism, no significant association with asthma risk was found in the overall population. However, a significant protective association was found in the Indian population in the dominant model comparison (OR = 0.72, 95% CI = 0.59–0.87, I² = 25%, studies = 5, cases = 1190, controls = 1241). A significant risk association was found in the Arab population in the dominant model comparison (OR = 1.75, 95% CI = 1.14–2.70, I² = 0%, studies = 2, cases = 307, controls = 361) and the homozygote model comparison (OR = 1.88, 95% CI = 1.17–3.02, I² = 0%, studies = 2, cases = 307, controls = 361), and in the Hispanic-Latino population in the dominant model comparison (OR = 1.68, 95% CI = 1.10–2.55, I² = 77%, studies = 5, cases = 1026, controls = 1412). For the rs1042714 polymorphism, we found a significant association in the recessive model comparison (OR = 0.83, 95% CI = 0.70–0.98, I² = 44%, studies = 52, cases = 8242, controls = 16,832), the homozygote genotype comparison (OR = 0.84, 95% CI = 0.72–0.98, I² = 25%, studies = 52, cases = 8242, controls = 16,832) and the allelic genetic model (OR = 0.91, 95% CI = 0.83–0.99, I² = 59%, studies = 52, cases = 8242, controls = 16,832) in the overall population. When stratified by age, a significant association was also found in children in the recessive model comparison (OR = 0.59, 95% CI = 0.39–0.88, I² = 58%, studies = 18, cases = 2498, controls = 2510) and the homozygote genotype comparison (OR = 0.63, 95% CI = 0.43–0.92, I² = 46%, studies = 18, cases = 2498, controls = 2510), but not in adult. For the rs1042711 polymorphism, no significant associations were found in the any genetic model.

Conclusion

The meta-analysis suggests that the ADRB2 rs1042714 polymorphism has a protective association with asthma in the overall population and the pediatric subgroup.

The Influence of Beta-2 Adrenergic Receptor Gene Polymorphisms on Albuterol Therapy for Patients With Asthma: Protocol for a Systematic Review and Meta-Analysis

Background

Albuterol is one of the most frequently used medications in clinical practice and seeing varying responses to albuterol between individuals is not uncommon. Multiple studies have been conducted to investigate the associations of differing responses due to albuterol, particularly with regards to the two nonsynonymous single nucleotide polymorphisms (SNPs) at positions 16 (Arg16Gly: substitution of arginine to glycine at position 16; rs1042713) and 27 (Glu27Gln: substitution of glutamic acid to glutamine at position 27; rs1042714) on the β-2 adrenergic receptor (ADRB2) gene. However, the directions of the correlations are conflicting.

Objective

The objective of this systematic review and meta-analysis is to assess the effect of the two SNPs on the ADRB2 gene, in terms of the responses that present in asthmatic patients shortly after albuterol inhalation.

Methods

The primary outcome of this work is a detailed study of the associations of the two SNPs in the ADRB2 gene with treatment response and lung function testing shortly after administration of albuterol to asthmatic patients. A comprehensive literature search, using the OVID platform, MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials, will be conducted by a specialized librarian without language restrictions. We will include both prospective and retrospective original observational studies, and we will exclude nonhuman or in vitro studies. All abstracts will be reviewed by two authors who will also individually perform data extraction from each eligible study. Any arising disagreements will be resolved through discussion with a third party. Risk of bias for all included studies will be independently assessed using the quality of genetic association studies tool. We will report the systematic review and meta-analysis, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. A narrative synthesis of study results or meta-analyses will be undertaken when appropriate.

Results

At the moment of writing, we have already started the preliminary literature search and piloting of the study selection process. The anticipated completion date is September 30, 2019.

Conclusions

Our systematic review and meta-analysis aims to clarify the current evidence of associations between the two nonsynonymous SNPs in the ADRB2 gene and the responses that present in asthmatic patients shortly after albuterol inhalation. If positive correlations are found, this knowledge may be used to improve personalized pharmacotherapy of albuterol use.

Trial Registration

PROSPERO CRD42019074554; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=74554

International Registered Report Identifier (IRRID)

PRR1-10.2196/14759

Polymorphisms in Beta-2 Adrenergic Receptor Gene and Association with Tuberculosis

PURPOSE

Genetic susceptibility for tuberculosis in human has been previously demonstrated. Polymorphisms in genes involved in immune responses may alter the susceptibility of individuals to tuberculosis. Polymorphisms of beta-2 adrenergic receptor (ADRB2) gene can be possibly an important risk factor in tuberculosis. In this study, the association between rs1042713 (Arg16Gly +46A>G) and rs1042714 (Gln27Glu +79C>G) polymorphisms in ADRB2 gene and tuberculosis was evaluated.

METHODS

Genotype distributions of the rs1042713 (Arg16Gly +46A>G) and rs1042714 (Gln27Glu +79C>G) polymorphisms in ADRB2 gene in 106 patients with pulmonary tuberculosis and 88 healthy subjects were studied by PCR-RFLP method in an Iranian population.

RESULTS

The frequency of rs1042713*G and rs1042714*G alleles in ADRB2 gene in tuberculosis patients was significantly different from healthy controls [odds ratio (OR) 0.176, 95% confidence interval (CI) 0.065-0.48, P value <0.001 and OR 0.45, 95% CI 0.247-0.825, P value = 0.009, respectively]. There were no significant differences in haplotype analysis between the patients and control subjects.

CONCLUSION

The association was reported between rs1042713 and rs1042714 polymorphisms in ADRB2 gene and tuberculosis for the first time. rs1042713*G and rs1042714*G polymorphisms in ADRB2 gene makes people more susceptible to develop the disease.