β2-AR Gene Research Articles

Association of β1- and β2-Adrenergic Receptor Gene Polymorphisms with the Effectiveness of Bisoprolol and Carvedilol in Patients with Heart Failure of Ischemic Etiology

The aim. To study the relationship between β1-, β2-adrenergic receptor (β-AR) gene polymorphisms and the effectiveness of bisoprolol and carvedilol in patients with heart failure (HF) and coronary heart disease. Materials and methods. We examined 201 patients with HF on the background of post-infarction cardiosclerosis. Control group included 43 healthy individuals of comparable age and sex. Genotyping was carried out for 3 polymorphisms (rs1801253 and rs1801252 of the β1-AR gene; rs1042714 of the β2-AR gene). The patients were divided into 2 groups: the first group included 104 (51.7%) patients who took bisoprolol during the year of observation; 97 (48.3%) patients of the second group were treated with carvedilol. Statistical analysis was performed using Statistica 10.0 and SNPStats programs. Results. In patients with HF, the mutant C-allele (rs1801253 polymorphism) of the β1-AR gene was associated with a decrease in the probability of heart rate reduction >15 min-1 against the background of the use of β-blocker during the year (odds ratio [OR] = 0.42 [0.16-0.98], p = 0.041, recessive inheritance model; OR = 0.62 [0.40-0.97], p = 0.038; log-additive inheritance model). The probability of positive dynamics of the left ventricular ejection fraction (LVEF) increased in carriers of the wild A-allele of the rs1801252 (Ser49Gly) polymorphism of the β1-AR gene (OR = 4.86 [2.35-10.08], p < 0.0001, codominant model; OR = 5.18 [2.51-10.68], p < 0.0001, dominant model; OR = 4.68 [2.26-9.68], p < 0.0001, over-dominant model; OR = 5.05 [2.48-10.28], p < 0.0001, log-additive inheritance model). The probability of an increase in LVEF within a year increased with treatment with carvedilol in homozygous mutant G/G rs1042714 polymorphism (Gln27Glu) of the β2-AR gene in patients with HF (OR = 6.09 [1.16-31.88], p = 0.038, dominant inheritance model). Conclusions. Patients with HF of ischemic etiology, carriers of the mutant C-allele of rs1801253 polymorphism of the β1-adrenoceptor gene, are worse responders to the use of β-blockers compared to patients with the wild G-allele (a lower proportion of patients with a decrease in heart rate >15 min-1: 6.8% vs. 14.5%, respectively; OR = 0.42 [0.16-0.98], p = 0.041). The frequency of an increase in the value of the LVEF >10% was higher compared to patients with the mutant G-allele (39.3% vs. 11.1%, respectively; OR = 4.86 [2.35-10.08], p < 0.0001) against the background of application of β-blockers. The use of carvedilol was more appropriate in homozygous carriers of the mutant G-allele of the rs1042714 polymorphism (Gln27Glu) of the β2-AR gene compared to bisoprolol (a greater proportion of patients with an increase in the LVEF: 17.6% vs. 9.1%, respectively; OR = 6.09 [1.16-31.88], p = 0.038). No probable associations of rs1801253 and rs1801252 polymorphisms of the β1-AR gene with the pharmacodynamics of bisoprolol and carvedilol in patients with HF of ischemic etiology were found.

Association of β1-, β2-Adrenoceptor and LGALS-3 Genes Polymorphisms with the Course of Heart Failure in Patients with Ischemic Heart Disease

The aim. To study the relationship between β1-, β2-adrenoceptor (β-AR) and LGALS-3 genes polymorphisms with the course of heart failure (HF) in patients with coronary heart disease. Materials and methods. We examined 201 patients with HF on the background of post-infarction cardiosclerosis. Control group included 43 healthy individuals of comparable age and sex. Genotyping was carried out for 4 polymorphisms (rs1801253 and rs1801252 of the β1-AR gene; rs1042714 of the β2-AR gene and rs2274273 of the LGALS-3 gene). Statistical analysis was performed using Statistica 10.0 and SNPStats programs. Results. In patients with HF, the A allele (A/G-A/A) of the rs1801252 polymorphism of the β1-AR was associated with a reduced risk of rehospitalization (RH) within a year (odds ratio [OR] = 0.44 [0.20-0 .98], p = 0.036, dominant inheritance model). The data on the reduction of the risk of RH in patients with HF in the presence of the A allele of the rs1801252 polymorphism of the β1-AR gene were also confirmed in the log-additive (OR = 0.44 [0.20-0.96], p = 0.027) and, mainly, in excessively dominant (OR = 0.48 [0.21-1.06], p = 0.059) inheritance models. The analysis showed a higher frequency of allele A of the rs1801252 polymorphism of the β1-AR gene in the group of patients with HF who did not have RH due to decompensation during the year, compared to patients with RH (14.9% versus 7.0%, respectively; χ2 = 4.304; p = 0.039). The A allele of the specified gene polymorphism was also associated with a reduced risk of persistent atrial fibrillation (AF) (OR = 0.34 [0.14-0.84], p = 0.018, dominant inheritance model). This regularity was confirmed in the overdominant (OR = 0.27 [0.11-0.69], p = 0.0048) and in the codominant (OR = 0.28 [0.11-0.72], p = 0.0081) inheritance models. The A allele (A/G-A/A) of the rs2274273 polymorphism of the LGALS-3 gene was associated with an increased risk of AF in patients with HF (OR = 6.63 [1.31-33.53], p = 0.032, codominant inheritance model). Data on the increase in the risk of AF, provided that the A allele of the aforementioned polymorphism is present, were also confirmed in the recessive (OR = 5.12 [1.08-24.24], p = 0.017) and log-additive (OR = 2.11 [1.13-3.94], p = 0.015) inheritance models. The risk of RH in patients with HF and concomitant diabetes mellitus increased in patients with heterozygous (G/C) polymorphism rs1801253 of the β1-AR gene (OR = 3.91 [1.03-14.87], p = 0.0041). Conclusions. The course of HF was associated with genetic differences β1-AR, in particular: the A allele of the rs1801252 polymorphism of the specified gene reduced the risk of RH within a year (14.1 % vs. 27.0 %; OR = 0.44; p = 0.036, dominant inheritance model) and AF (18.3 % vs. 39.5 %; OR = 0.34; p = 0.018, dominant inheritance model). The risk of RH of patients with HF and accompanying diabetes mellitus was higher with heterozygous (G/C) rs1801253 polymorphism of the β1-AR gene (24.4 % vs. 11.1 %; OR = 3.91; p = 0.0041). The A allele of the rs2274273 polymorphism of the LGALS-3 gene was associated with an increased risk of AF in patients with HF (20.0 % vs. 4.7%; OR = 6.63, p = 0.032, codominant inheritance model). No probable association of the rs1042714 polymorphism of the β2-AR gene with the course of HF was found.

CLINICAL COURSE OF OBESITY-ASSOCIATED ASTHMA DEPENDING ON THE GLN27GLU POLYMORPHIC VARIANT OF THE β2-ADRENORECEPTOR GENE, TAKING INTO ACCOUNT THE AGE OF ONSET

Introduction. Studies have shown that bronchial asthma (BA) associated with obesity has a more severe course, lower control, more frequent cases of low efficacy of basic treatment, and exacerbations. Two phenotypes have been distinguished in BA-obesity comorbidity based on age of onset: early atopic and late non-atopic. It is known that genetic factors associated with β2-adrenoceptor (AR) genes are important in the development of both asthma and obesity.
 The purpose of the study aimed to analyze the association of the Gln27Glu polymorphism of the β2-adrenoceptor gene with the severity of the course of bronchial asthma with obesity, taking into account the age of its onset.
 Research material and methods. 195 asthma patients with obesity consented for the study participation were examined. The control group consisted of 95 practically healthy people. Patients were divided into two clinical groups depending on the age of onset of BA: the first group included 100 patients with an early onset, the second group - 95 patients with a late onset. The diagnosis and treatment of asthma followed the guidelines of the Global Initiative for Asthma (2016) and its updated versions. The study was approved by the Bioethics Commission of the Educational and Scientific Medical Institute of Sumy State University. Determination of the Gln27Glu polymorphism of the β2-AR gene (rs1042714) was performed using the polymerase chain reaction with the subsequent analysis of restriction fragments. Statistical analysis of the obtained results was carried out using the SPSS-17 program. Pearson's chi-squared test was used to compare genotype distributions between experimental groups. To determine the risk of BA and obesity, odds ratios and 95% confidence intervals were calculated for dominant, recessive, superdominant, and additive models of inheritance. Their relevance was assessed using the Akaike information criterion. All tests were two-sided, and values p < 0.05 were considered statistically significant.
 Research results. The frequency of Gln/Gln, Gln/Glu and Glu/Glu genotypes according to the Gln27Glu polymorphism of the β2-AR gene in patients with early-onset obesity-associated asthma was 70.0; 25.0; 5.0% with a mild course and 55.0; 36.2; 8.8% with severe (χ2 = 1.49; p = 0.473); and with a late debut - 50.0; 43.8; 6.2% with mild and 54.0%; 31.7; 14.3%, respectively, with severe (χ2 = 2.10; p = 0.350). Despite the absence of a probable difference in the distribution of genotypes depending on the severity of the course, it was found that the frequency of homozygotes for the minor allele was 1.8 times higher in patients with a severe course of early BA and 2.3 times higher in late BA compared to that in patients with mild BA course.
 The risk of early-onset BA with obesity and a severe course showed no association in all models of inheritance, and in patients with late-onset BA, there was a 1.66-fold increase (95% CI (1.03 – 2.72), p = 0.04) in the additive inheritance model (p = 0.04).
 Conclusions. There are no statistically significant differences in the distribution of genotypes according to the Gln27Glu polymorphism of the β2-AR gene depending on the severity of the course of early and late BA with obesity. The risk of developing a severe course of early BA did not depend on the Gln27Glu polymorphism of the β2-AR gene, and late BA increased by 1.66 times in the additive model of inheritance.

THE ASSOCIATIONS OF β-ADRENORECEPTORS GENES POLYMORPHISMS WITH THE COURSE OF HEART FAILURE AND WITH THE LOW TRIIODOTHYRONINE SYNDROME (LITERATURE REVIEW AND OWN OBSERVATIONS)E

The systematization of literature data on the associations of β-adrenoreceptors (β-AR) genes polymorphisms with the course of heart failure (HF) and with the development of low triiodothyronine syndrome (LT3S), and the results of our own study were presented. The study of associations of β-AR system genes polymorphisms with the clinical outcome of HF and the effectiveness of β-adrenoblockers (β-AB) has been continued. It has been demonstrated that carrier state of the A allele of the Ser49Gly (c.145A > G) polymorphism of the b1-AR gene leads to a decrease in the risk of combined end point. At the same time, the carrier state of the G allele of the Gln27Glu (c.79C> G) polymorphism of the b2-AR gene increases the risk of combined end point. Administration of bisoprolol at a dose of > 5 mg leads to a reduction of the risk of the combined endpoint, provided the G/A genotype of the Ser49Gly (c.145A > G) polymorphism of the β1-AR gene is present. The use of bisoprolol at this dose also reduces the risk of re-hospitalisation and combined endpoint, provided the homozygous genotype (C/C) of the Gln27Glu (c.79C > G) polymorphism of the β2-AR gene is present. The probability of the low triiodothyronine syndrome increases with the homozygous G/G genotype of the Gln27Glu polymorphism of the β2-AR gene and in the presence of the C/T polymorphism of the Serβ75 GNβ3 gene. The genotype C/G of the Gln27Glu polymorphism of the β2-AR gene is associated with a decreased risk of LT3S.

Abstract 6721: β3-adrenergic receptor correlates with tumor growth and progression in neuroblastoma

Abstract Neuroblastoma (NB) is a heterogeneous, often aggressive, extracranial tumor and the most common malignancy to be diagnosed in the first year of life. It has been already demonstrated that the specific antagonism of the β3-adrenergic receptor (β3-AR) on NB tumor cells affects tumor growth. To confirm the results obtained with the pharmacological approach on the crucial role played by the β3-AR receptor in influencing different pro-tumoral signaling pathways, here we investigated the effect of CRISPR/Cas9-mediated knock-out of β3-AR gene (ADRB3) on human NB cell line BE(2)-C in vitro and in vivo. Inoculation of BE(2)-C β3-AR−/- cells in athymic nude mice (NU(N-Cr)-Foxn1nu) showed a strong reduction of NB tumor growth compared to wild type cells, and in some cases β3-AR knock-out tumor cells failed in producing a tumor mass. RNA Sequencing on these tumor masses showed alterations of signaling pathways related to various tumor mechanisms, such as proliferation, cell motility and cell differentiation. Furthermore, we evaluated by flow cytometry the expression of β3-AR in circulating tumor cells (CTCs) from NB patients with different degrees of disease. Following depletion with anti-CD45 magnetic beads, tumor cells were identified through the expression of specific tumor markers, CD56 and GD2. Results showed that a high expression of β3-AR correlates with poor prognosis, characterized by metastatic or recurrent tumors, compared to patients with a favorable clinical outcome that instead show a low expression of β3-AR. Overall, our results demonstrate the β3-AR involvement in supporting NB tumor growth and suggest a possible role in regulating the metastatic potential of this tumor. Citation Format: Alessia Boaretto, Gennaro Bruno, Nicoletta Nastasi, Claudio Favre, Maura Calvani. β3-adrenergic receptor correlates with tumor growth and progression in neuroblastoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6721.

GLN27GLU POLYMORPHISM IN THE Β2-ADRENORECEPTOR GENE IN PATIENTS WITH ASTHMA WITH REGARD TO THE AGE OF ONSET

Aim: The study aimed to assess the frequency of the Gln27Glu polymorphic variant in the β2-AR gene among patients with early and late-onset asthma and assess asthma risks depending on the disease phenotype. Materials and Methods: Our study included a total of 553 asthma patients who consented to participate in the study. Asthma was diagnosed according to the 2016 GINA recommendations and its later versions. The study was approved by the Bioethics Committee of the Medical Institute of Sumy State University. The analysis for determining genetic polymorphism (designated as rs1042714) was conducted through the use of polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis of obtained results was performed using SPSS–17 program. Results: It was found that there is a significant difference in the distribution of alleles and genotypes in people with early-onset asthma compared to those with late-onset asthma; the statistical analysis showed a χ2 value of 41.75 and p-value of 0.001 for early-onset asthma, and a χ2 value of 44.24 and p-value of 0.001 for late-onset asthma. We did not observe a significant increase in the early-onset asthma risk with an account of different inheritance models connected to the studied polymorphism. Research that took into account the risk of late-onset asthma discovered statistically significant results regarding the dominant (p = 0.001), super-dominant (p = 0.001), and additive (p = 0.001) models of inheritance. Conclusions: Based on the data collected, it was found that individuals carrying the minor allele (both homozygotes and heterozygotes) were at a greater risk of developing asthma later in life. However, no such correlation was observed in patients with early-onset asthma.

Association between the Ile164 β2 Adrenergic Receptor Polymorphism and Fatigue in Patients with Rheumatoid Arthritis

Introduction: In the present work, the frequency of inherited polymorphisms of the beta 2 adrenergic receptor (β2AR) gene and their association with fatigue in patients with rheumatoid arthritis (RA) was examined. Methods: An allele-specific polymerase chain reaction was used to determine the common variants of the β2AR at position 16, 27, and 164 in 92 German RA outpatients. Health Assessment Questionnaire (HAQ-DI), Beck Depression Inventory (BDI), Perceived Stress Questionnaire (PSQ-30), Multidimensional Fatigue Inventory (MFI-20) were utilized. Results: 34.7% of German RA patients were diagnosed with associated fatigue. Fatigued patients were more likely to carry the Ile allele at position 164 (OR 7.33, 95% CI 1.09–59.8, p = 0.049). Comparing these risk factors’ contribution to different fatigue dimensions revealed that Ile164 carriers only had significantly higher MFI-20 mean values for general fatigue (p = 0.014) while the clinical difference among other MFI subscales was the largest for mental fatigue (carrier: 8.23, SD: 4.22, noncarrier: 5.67, SD: 1.56, p = 0.089, Cohen’s d = 0.629). Disease activity, perceived stress, and depression were also associated with fatigue with higher mean values for DAS28CRP (p = 0.038), PSQ (p < 0.001), and BDI-II (p < 0.001) in fatigued patients. Physical fatigue was correlated with disease activity (p = 0.009) and depression (p = 0.001) while mental fatigue showed associations with depression (p = 0.001) and perceived stress (p = 0.028). Conclusion: The discovery study indicates that the Ile164 polymorphism might in contrast to other β2AR polymorphisms affect fatigue levels in RA patients. This association was observed especially with mental fatigue. Further replication studies are warranted to determine further role of β2AR polymorphisms in RA patients.

Correlation between Adrenoceptor Expression and Clinical Parameters in Degenerated Lumbar Intervertebral Discs

Despite advanced knowledge of the cellular and biomechanical processes of intervertebral disc degeneration (IVDD), the trigger and underlying mechanisms remain unclear. Since the sympathetic nervous system (SNS) has been shown to exhibit catabolic effects in osteoarthritis pathogenesis, it is attractive to speculate that it also influences IVDD. Therefore, we explored the adrenoceptor (AR) expression profile in human IVDs and correlated it with clinical parameters of patients. IVD samples were collected from n = 43 patients undergoing lumbar spinal fusion surgery. AR gene expression was analyzed by semi-quantitative polymerase chain reaction. Clinical parameters as well as radiological Pfirrmann and Modic classification were collected and correlated with AR expression levels. In total human IVD homogenates α1A-, α1B-, α2A-, α2B-, α2C-, β1- and β2-AR genes were expressed. Expression of α1A- (r = 0.439), α2A- (r = 0.346) and β2-AR (r = 0.409) showed a positive and significant correlation with Pfirrmann grade. α1A-AR expression was significantly decreased in IVD tissue of patients with adjacent segment disease (p = 0.041). The results of this study indicate that a relationship between IVDD and AR expression exists. Thus, the SNS and its neurotransmitters might play a role in IVDD pathogenesis. The knowledge of differential AR expression in different etiologies could contribute to the development of new therapeutic approaches for IVDD.

The Effect of Swimming Training with Cinnamon Consumption on β3-AR and ERK2 Gene Expression in the Visceral Adipose Tissue of Diabetic Rats

Background: β3-AR is an important factor involved in the activation of ERK protein signaling cascade, which can positively contribute to the regulation of adipose tissue metabolism and its conversion into brown adipose tissue. Diabetes mellitus can lead to dysfunction of these factors. Objectives: The current study aimed to investigate the effect of swimming training combined with cinnamon consumption on β3-AR and ERK2 gene expression in the visceral adipose tissue from diabetic rats. Methods: In this experimental-fundamental study, 35 male Wistar rats (mean weight: 200 ± 20 g) were selected and randomly assigned into four groups after the induction of diabetes by streptozotocin. These groups included: (1) healthy control, (2) control, (3) swimming, (4) cinnamon, and (5) swimming cinnamon (n = 7 in each group). The training groups were put through a five-days-a-week workout for four weeks according to the training protocol. Gene expression levels were measured by in vitro real-time PCR. The collected data were analyzed using one-way ANOVA and Tukey’s post hoc test. Results: The expression levels of β3-AR and ERK2 protein genes in the visceral adipose tissue of diabetic rats (P = 0.0001) were significantly affected by swimming training and cinnamon consumption. Conclusions: It was shown that cinnamon supplementation may have increased β3-AR levels, which was more effective than training, while training had a greater effect on ERK2 levels and increased them. Therefore, it was concluded that cinnamon consumption combined with training may have greatly contributed to the conversion of white adipose into brown adipose tissues.

Expression pattern and clinical significance of beta 2-adrenergic receptor in oral squamous cell carcinoma: an emerging prognostic indicator and future therapeutic target.

Beta 2-AdrenergicReceptor (β2-AR) is significantly overexpressed in various types of malignancies, which is associated with the worst prognosis. However, the role of β2-AR in oral cancer is not well identified. The present study aimed at investigating the β2-AR gene expression and its significance in relation withthe clinicopathological features and overall survival of oral squamous cell carcinoma (OSCC) patients. Immunohistochemistry, western blot and quantitative real-time PCR techniques were used to analyze β2-AR protein and mRNA levels in a total of 65 histopathologically confirmed OSCC tissues (case group) and 65 normal tissues (control group) from the oral cavity. Out of the total of 65 OSCC tissues, 41 tissues (63.1%) exhibited high expression for β2-AR protein. Percent positivity and relative density (mean ± SD) of protein were higher in the case group ascompared to the control group (positivity 40.31 ± 3.01 vs. 20.46 ± 1.93, p < 0.001; density 2.77 ± 1.17 vs. 1.28 ± 0.37, p < 0.001). In addition, β2-AR mRNA level was also upregulated in patients comparedtothe controls (2.36 ± 1.30 vs. 1.09 ± 0.42, p < 0.001) and showed a positive correlation with immunostaining of protein in OSCC (r = 0.48, p = 0.011). High β2-AR protein expression was significantly associated with multiple risk habits (p = 0.045), histological differentiation (p = 0.013), clinical TNM stages (p = 0.014), and poor survival (p = 0.006) of patients. In the Cox proportional hazards model, β2-AR was identified as a prognostic biomarker of OSCC (p = 0.047). β2-AR protein level is identified as an independent significant prognostic factor in patients with oral carcinoma.

HIF-1-Dependent Induction of β3 Adrenoceptor: Evidence from the Mouse Retina.

A major player in the homeostatic response to hypoxia is the hypoxia-inducible factor (HIF)-1 that transactivates a number of genes involved in neovessel proliferation in response to low oxygen tension. In the retina, hypoxia overstimulates β-adrenoceptors (β-ARs) which play a key role in the formation of pathogenic blood vessels. Among β-ARs, β3-AR expression is increased in proliferating vessels in concomitance with increased levels of HIF-1α and vascular endothelial growth factor (VEGF). Whether, similarly to VEGF, hypoxia-induced β3-AR upregulation is driven by HIF-1 is still unknown. We used the mouse model of oxygen-induced retinopathy (OIR), an acknowledged model of retinal angiogenesis, to verify the hypothesis of β3-AR transcriptional regulation by HIF-1. Investigation of β3-AR regulation over OIR progression revealed that the expression profile of β3-AR depends on oxygen tension, similar to VEGF. The additional evidence that HIF-1α stabilization decouples β3-AR expression from oxygen levels further indicates that HIF-1 regulates the expression of the β3-AR gene in the retina. Bioinformatics predicted the presence of six HIF-1 binding sites (HBS #1-6) upstream and inside the mouse β3-AR gene. Among these, HBS #1 has been identified as the most suitable HBS for HIF-1 binding. Chromatin immunoprecipitation-qPCR demonstrated an effective binding of HIF-1 to HBS #1 indicating the existence of a physical interaction between HIF-1 and the β3-AR gene. The additional finding that β3-AR gene expression is concomitantly activated indicates the possibility that HIF-1 transactivates the β3-AR gene. Our results are indicative of β3-AR involvement in HIF-1-mediated response to hypoxia.

GLN27GLU polymorphism in the β2-adrenergic receptor gene in patients with bronchial asthma

The aim of the study was to analyze the frequency of the polymorphism in the β2-adrenoceptor (Gln27Glu) gene in patients with bronchial asthma (BA) and to assess the association of the polymorphism with disease risks. Materials and methods. A total of 553 patients with BA and 95 apparently healthy individuals were examined. The Gln27Glu polymorphism in the β2-АR gene (rs1042714) was determined using polymerase chain reaction-restriction fragment length polymorphism analysis. Statistical analysis of the results was performed using SPSS-17 program. Results. The allele and genotype distribution of the Gln27Glu polymorphism in the β2-АR gene in apparently healthy individuals and BA patients was consistent with Hardy–Weinberg equilibrium (P &gt; 0.05). The analysis revealed that heterozygotes for the Gln27Glu polymorphic variant in the β2-АR gene were more frequent among BA patients vs. apparently healthy individuals (P = 0.018). The minor allele homozygotes (Glu/Glu) were 1.5 times more frequent among BA patients vs. the controls only in terms of trends without statistical significance. There was no statistically significant difference in the genotype distribution of the studied polymorphic variant between men and women in the control group and BA patient group (P = 0.55; P = 0.47). The analysis of BA risk showed a statistically significant association within the dominant (P = 0.01), super-dominant (P = 0.02), and additive (P = 0.01) models. The minor allele carriers Glu (predominantly heterozygotes) had 1.9 times higher risk of BA in the dominant model and 1.6 times higher risk of BA in the additive model vs. the major allele homozygotes. Conclusions. The statistically significant difference in the distribution of the homozygous and heterozygous genotypes of the β2-AR gene (Gln27Glu) polymorphism was found between asthma patients and apparently healthy individuals regardless of sex. The minor allele carriers (Gln/Glu genotypes) had the higher risk of BA vs. the major allele homozygotes.

Abstract 9084: Selective Beta3-Adrenergic Receptor Antagonist Therapy Causes Regression of Cardiac Dysfunction in a Rat Model of Progressive Heart Failure: Insights into Molecular and Cellular Mechanisms

Background: Heart failure (CHF) causes cardiac β 3 -adrenergic receptor (AR) upregulation with resultant enhanced β 3 -AR-stimulated-G i -coupled negative modulation on cardiac function. This suggests a direct and contributing role of β 3 -AR activation on CHF progression. However, its precise role is unclear. We hypothesize that up-regulation of cardiac β 3 -AR promotes CHF progression. Chronic β 3 -AR antagonist (ANT) may improve Left ventricular (LV) myocyte function, and β-adrenergic reserve, thus preventing the progression of CHF. Methods: LV and myocyte functional response and β 1 - and β 3 -AR expression were compared in 3 groups of SD male rats (8 each) during 3 months: 1) CHF, 3 months after receiving Isoproterenol (ISO, 170 mg/kg, sq, for 2 days); 2) CHF/β 3 -ANT, 2 months after receiving ISO, L-748,337, a selective β 3 -AR antagonist (β 3 -ANT) (10 -7 M/kg/day, mini pump) was initiated and was given for 1 month; and 3) sham controls. Results: Versus controls, ISO-treated rats had CHF onset at 1 month after ISO and progressed to severe CHF at 3 months. Plasma norepinephrine (NE, 1298 vs 261 pg/ml) increased 4-fold; whereas, stroke volume (SV) and ejection fraction (EF, 34 vs 62%) decreased more than 45%. These changes were parallel with significant reductions in cell contraction (dL/dt max , 95 vs 189 μm/s), relaxation (dR/dt max ,75 vs 158 μm/s) and [Ca 2+ ] i transient ([Ca 2+ ] iT ) (0.17 vs 0.26). Acute superfusion of ISO (10 -8 M) caused much less increases in dL/dt max (34 vs 74%), dR/dt max and [Ca 2+ ] IT (14 vs 28%). These changes were associated with significantly decreased β 1 -AR mRNA (52%, 0.30 vs 0.62), but increased β 3 -AR mRNA (119%, 1.25 vs 0.57) expression. CHF with β 3 -ANT treatment, significantly decreased plasma NE (197 pg/ml). EF (59%) and SV returned to normal control values. The signal ratios of β 1 -AR mRNA (0.59) and β 3 -AR mRNA (0.66) recovered to control levels. ISO-induced increases in dL/dt max (75%), dR/dt max and [Ca 2+ ] iT were also significantly augmented. Conclusion: Chronic β 3 -ANT leads to normalization of LV myocyte β 1 - and β 3 -AR gene expression, restores normal LV myocyte β-AR reserve, and leads to regression of LV and myocyte dysfunction in a rat model of progressive CHF. Thus, β 3 -AR blocker may provide a new therapeutic strategy for the treatment of CHF.

ANALYSIS OF THE ASSOCIATION OF BRONCHIAL ASTHMA CLINICAL COURSE WITH Arg16Gly POLYMORPHIC VARIANT IN THE β2-ADRENOCEPTOR GENE

Relevance. The relevance of the study of Arg16Gly polymorphism of the β2-adrenoceptor (β2-AR) gene is due to the fact that a number of studies have proven its role in the development of bronchial asthma (BA), bronchial hyperactivity, the effectiveness of basic treatment. However, these associations show low reproducibility in various studies, so the question of the possibility of clinical application of the results of genetic testing for Arg16Gly polymorphic variant of the β2-AR gene remains unanswered. The main reasons why the clinical significance of this polymorphism is not confirmed in various studies are - population heterogeneity, insufficient sample size, improper characterization of comparison groups.&#x0D; Objective: to study the association of Arg16Gly polymorphism in the β2-adrenoceptor gene with BA clinical course taking into account the age of onset.&#x0D; Materials and methods. We examined 553 BA patients (group I included 282 patients with late-onset asthma and group II included 271 patients with early-onset asthma) and 95 apparently healthy individuals. The study has been approved by the Bioethics Committee of Medical Institute of Sumy State University. Arg16Gly polymorphism in the β2-АR gene (rs1042713) was determined using polymerase chain reaction-restriction fragment length polymorphism analysis. Statistical analysis of obtained results was performed using SPSS–17 program.&#x0D; Results. There was no significant difference in the distribution of genotypes for Arg16Gly polymorphism in the β2-AR gene depending on asthma severity with no regard for the age of onset (χ2 = 5.14; p = 0.27). With regard for the age of onset, we found out that early-onset BA was linked to a difference in genotype distribution for this polymorphic variant in patients with severe and non-severe course (χ2 = 14.76; р = 0.001). The frequency of Gly/Gly genotype was higher in patients with severe course (41.4%) as compared to patients with mild course (16.4%), while the frequency of Arg/Arg (32.9%) and Arg/Gly (50.7%) genotypes was higher in patients with mild asthma as compared to patients with severe course (24.3% and 34.3%). There was no significant difference in the distribution of genotypes in patients with late-onset asthma with regard to course severity (χ2 = 4.94; p = 0.084).&#x0D; The relative risk of severe course for early-onset asthma was 3.84 times higher (95% CI 2.11–7.36; p = 0.001) in the recessive model, 2.58 times higher (95% CI 1.53–4,37, p = 0.001) in the dominant model, and 2.16 times (95% CI 1.56–3.04) higher in the additive model. In patients with late-onset asthma, no association was found in all models.&#x0D; Conclusions. There was no significant difference in the distribution of genotypes for Arg16Gly polymorphism in the β2-AR gene depending on asthma severity with no regard for the age of onset. When adjusted for the age of onset, the analysis revealed a difference in genotype distribution for this polymorphic variant in patients with severe and non-severe course having early-onset BA (р = 0.001). The frequency of Gly/Gly genotype was higher in patients with severe course as compared to patients with mild course. For patients with late-onset asthma, no differences were found (p = 0.084). Heterozygous and homozygous Gly allele carriers have a higher risk of early-onset asthma only.

Differential β‐arrestin2 binding of the human β 1 ‐adrenoceptor Arg389Gly polymorphic variants in cardiac myocytes

Rationale The β1-adrenergic receptor (AR) is the primary receptor in cardiomyocytes through which catecholamines increase cardiac function, i.e. contractility and heart rate (positive inotropy and chronotropy). The human β1AR gene (Adrb1), which encodes a G protein-coupled receptor (GPCR), displays high nucleotide sequence variability. One of its several non-synonymous polymorphisms identified to date is the Gly/Arg variation at aminoacid position 389 (C1165G in the open reading frame's nucleotide sequence), with the Arg389 variant being much less frequent in African-Americans than in Caucasians (58% vs. 73%, respectively). Since amino acid 389 is located in the intracellular C-terminus of the encoded receptor, this polymorphism is expected, and has been shown to affect both signaling/function and desensitization of the β1AR. Indeed, Arg389 β1AR has been found to be hyperfunctional, compared to its Gly389 counterpart, in transfected cell lines and in cardiomyocytes in vitro. It is also known to affect the response of individuals to the cardiac stimulant (β1AR-agonist) dobutamine, as well as the responses of heart failure patients to several β-blockers (β1AR-antagonists), including carvedilol, to which the Arg allele confers greater responses. Consistent with this, homozygous Arg389 heart failure patients seem to fare much better than their homozygous Gly389 or heterozygous Arg389Gly counterparts when treated with the same β-blocker drug, a finding that has led to the idea of utilizing genotyping for the β1AR Arg389Gly polymorphism for the purposes of stratification of heart failure patients and of tailoring their b-blocker therapy. Objective To examine the interaction of the two β1AR variants with the signal transducers β-arrestins in neonatal rat ventricular myocytes (NRVMs), in order to identify molecular mechanisms underlying their functional differences. Methods We tested the interaction of the polymorphic β1ARs with β-arrestins via β1AR immunoprecipitation followed by β-arrestin immunoblotting in NRVM protein extracts. Results The β-arrestin1 isoform binds both variants equally well in NRVMs. Conversely, the potentially beneficial in the heart β-arrestin2 isoform interacts only with the Arg389 receptor (not with the Gly389 allele) in NRVMs. Conclusion Arg389 confers unique β-arrestin2-interacting properties to the β1AR in cardiac myocytes, potentially underlying this variant's gain-of-function phenotype.

The Role of bone marrow-derived dendritic Cells in a stressed beta2 adrenergic receptor knockout male mice during Chlamydia muridarum lung infection.

Recent studies have shown that Chlamydia muridarum causes a lung infection that resembles pneumonia of C. trachomatis in humans. However, the mechanism(s) of the infection is/are not well defined. Dendritic cells (DCs) play a significant role in protection against Chlamydia genital infections, but their role during stressful conditions is unknown. This study is to examine the role of bone marrow-derived dendritic cells (BMDCs) in beta2-adrenergic receptor (β2-AR) knockout (KO) male mice during C. muridarum lung infection. We hypothesized that the lack of β2-AR leads to decreased organ load of C. muridarum in mice lung infection. We also hypothesized that BMDCS from β2-AR KO mice restored the normal function of cytokine production and served as an antigen-presenting activity to CD4+T cells. Stressed and non-stressed C57BL/6J wildtype (WT) and β2-AR gene knockout mice will be infected. Lysates of lungs will be tested for isolation of C. muridarum. Cells will be for Differentiation and proliferation of BMDCs will be performed to detect cytokine production. Results should correspond to our working hypothesis, which includes the lack of (β2-AR) leads to decreased organ load of C. muridarum in lung infection. Results will show significant differences between stressed 2-AR KO and stressed of WT. Moreover, increased protective cytokine production in stressed 2-AR KO compared to decreased cytokines production in stressed WT will be observed. Our findings may suggest that mice lacking b2 AR have reverted to protective cytokine production to reduce infection, and the function of BMDCs as antigen-presenting cells will be restored in KO mice.

Decreased Chlamydia muridarum genital infection and improved immune response in a β2-Adrenergic Receptor Knockout Mouse Stress Model

Chlamydia genital infection caused by Chlamydia trachomatis shows a high prevalence in low socioeconomic populations; however, whether stress is associated with the high prevalence of infection is not known. During chronic stress conditions, the interaction of beta2-adrenergic receptor (β2-AR) with norepinephrine (NE) is known to suppress the immune system in humans and animal models. However, the mechanism of suppression that leads to chlamydia infection is not well known. This study aims to measure the susceptibility of mice and cytokine production of a β2-AR knockout (KO) during Chlamydia muridarum genital infection. Stressed and non-stressed C57BL/6J wildtype (WT) and β2-AR gene KO mice will be infected with C. muridarum intravaginally post 21-day stressing period. Swabbing of mice at the 3-day interval for 42 days will be performed to determine C. muridarum counts and isolation. Moreover, splenic CD4+ T cells, bone marrow-derived dendritic cells at day 7 post-infection will be performed for immune response analysis by ELISA. We hypothesize that the deficiency of β2-AR leads to significantly less C. muridarum shedding from the genital tract of stressed KO and leads to an increase and decrease in the production of protective and suppressive cytokines, respectively. We anticipate results obtained will align with our central hypothesis that stressed WT mice have increased C. muridarum shedding of genital tracts and increased production of protective cytokines in stressed β2-AR KO, suggesting the importance of stress in β2-AR stimulation.

Association between Arg16Gly Polymorphism in the &amp;lt;i&amp;gt;Β&amp;lt;sub&amp;gt;&amp;lt;span style=&amp;quot;font-family:Verdana;&amp;quot;&amp;gt;2&amp;lt;/span&amp;gt;&amp;lt;/sub&amp;gt;&amp;lt;span style=&amp;quot;font-family:Verdana;&amp;quot;&amp;gt;&amp;lt;/i&amp;gt;-Adrenergic Receptor Gene and Obesity Risk in Patients with Bronchial Asthma

The objective of our study was to investigate the association between the Arg16Gly polymorphism in the β2-АR gene and body mass index (BMI) in patients with bronchial asthma (BA) with regard to the age of onset. Materials and methods: 553 patients were examined. The control group consisted of 95 apparently healthy individuals. The patients were divided into 2 groups depending on the age of BA onset: 282 patients with late onset (Group I) and 271 patients with early onset (Group II). Arg16Gly polymorphism in the β2-АR gene (rs1042713) was determined using polymerase chain reaction- restriction fragment length polymorphism analysis. Statistical analysis of obtained results was performed using SPSS–17 program. Results: There was no significant difference in the distribution of genotypes for Arg16Gly polymorphism in the β2-AR gene depending on BMI (χ2 = 5.74; р = 0.22), and no association was found with obesity risks disregarding the age of BA onset. The study on the frequency of genotypes for this polymorphism with regard to the age of asthma onset and BMI found statistically significant differences between early-onset (χ2 = 11.27; p = 0.02) and late-onset (χ2 = 10.66; p = 0.03) asthma. It was found that the risk of obesity in Group I patients was 1.57 times higher in the additive model and 2.67 times higher—in the recessive model of inheritance. In patients with late-onset asthma, Gly16 allele in the recessive model of inheritance was found to have a protective role against obesity. Conclusions: There was no significant difference in the distribution of genotypes for Arg16Gly polymorphism in the β2-AR gene with regard to BMI, and no association was found with obesity risks in BA patients disregarding the age of BA onset. The risk of obesity in patients with early-onset asthma was 1.6 times higher in the additive model and 2.7 times higher—in the recessive model of inheritance.

ARG16GLY POLYMORPHISM IN THE Β2-ADRENOCEPTOR GENE IN PATIENTS WITH BRONCHIAL ASTHMA

The aim: The objective of the study was to analyze the frequency of Arg16Gly polymorphism in the β2 -adrenoceptor (β2 -АR) gene in patients with bronchial asthma (BA) and to assess the association of the polymorphism with BA risk. Materials and methods: We examined 553 BA patients and 95 apparently healthy individuals. Arg16Gly polymorphism in the β2 -АR gene (rs1042713) was determined using polymerase chain reaction-restriction fragment length polymorphism analysis. Statistical analysis of obtained results was performed using SPSS-17 program. Results: It was established that distribution of Arg/Arg, Arg/Gly, and Gly/Gly genotypes for Arg16Gly polymorphism in the β2 -АR gene was 44.2%, 40.0%, 15.8% in the control group vs. 31.3%; 45.7% and 23.0 among BA patients, respectively (χ2 = 6.59; р = 0.037). No significant difference was observed with regards to the distribution of genotypes for Arg16Gly polymorphism in the β2 -АR gene in men and women controls (χ2 = 4.05; р = 0.13) and BA patients (χ2 = 4.34; р = 0.11). BA risk was 1.74 times higher in the minor allele carriers (Arg/Gly + Gly/Gly genotypes) for Arg16Gly polymorphism in the β2 -АR gene. Conclusions: Analysis of Arg16Gly polymorphic variants in the β2-AR gene showed a statistically significant difference in the distribution of Arg/Arg, Arg/Gly, and Gly/Gly genotypes in patients with BA and apparently healthy individuals due to the higher frequency of Arg/Arg genotype in controls and higher frequency of Gly/Gly genotype in patients with asthma. No difference with regard to gender was found in the distribution of genotypes.

Importance of β2AR elevation for re-endothelialization capacity mediated by late endothelial progenitor cells in hypertensive patients.

Dysfunction of late endothelial progenitor cells (EPCs) has been suggested to be associated with hypertension. β2-Adrenergic receptor (β2AR) is a novel and key target for EPC homing. Here, we proposed that attenuated β2AR signaling contributes to EPCs dysfunction, whereas enhanced β2AR signaling restores EPCs' functions in hypertension. EPCs derived from hypertensive patients exhibited reduced cell number, impaired in vitro migratory and adhesion abilities, and impaired re-endothelialization after transplantation in nude mice with carotid artery injury. β2AR expression of EPCs from hypertensive patients was markedly downregulated, whereas the phosphorylation of the p38 mitogen-activated protein kinase (p38-MAPK) was elevated. The cleaved caspase-3 levels were elevated in EPCs. The overexpression of β2AR in EPCs from hypertensive patients inhibited p38-MAPK signaling, whereas it enhanced in vitro EPC proliferation, migration, and adhesion and in vivo re-endothelialization. The β2AR-mediated effects were attenuated by treating the EPCs with a neutralizing monoclonal antibody against β2AR, which could be partially antagonized by the p38-MAPK inhibitor SB203580. Moreover, shear stress stimulation, a classic nonpharmacological intervention, increased the phosphorylation levels of β2AR and enhanced the in vitro and in vivo functions of EPCs from hypertensive patients. Collectively, the current investigation demonstrated that impaired β2AR/p38-MAPK/caspase-3 signaling at least partially reduced the re-endothelialization capacity of EPCs from hypertensive patients. Restoration of β2AR expression and shear stress treatment could improve their endothelial repair capacity by regulating the p38-MAPK/caspase-3 signaling pathway. The clinical significance of β2AR in endothelium repair still requires further investigation.NEW & NOTEWORTHY Impaired β2-adrenergic receptor (β2AR) expression with an elevation of p38-MAPK/caspase-3 signaling at least partially contributes to the decline of re-endothelialization capacity of late endothelial progenitor cells (EPCs) from hypertensive patients. β2AR gene transfer and shear stress treatment improve the late EPC-mediated enhancement of the re-endothelialization capacity in hypertensive patients through activating β2AR/p38-MAPK/caspase-3 signaling. The present study is the first to reveal the potential molecular mechanism of the impaired endothelium-reparative capacity of late EPCs in hypertension after vascular injury and strongly suggests that β2AR is a novel and crucial therapeutic target for increasing EPC-mediated re-endothelialization capacity in hypertension.