Convergent Evidence Supports TH2LCRR as a Novel Asthma Susceptibility Gene.

Asthma is a common, complex disease with apparent genetic predispositions, and previous genome-wide association studies suggest that rs1295686 within the IL13 (IL-13) gene is significantly associated with asthma. Analysis of the data provided by the 1,000 Genomes Project indicated an additional four SNPs in nearly complete linkage disequilibrium with rs1295686 in White people. However, the causal SNPs and the associated mechanism remain unclear. To investigate this issue, functional genomics approaches were utilized to analyze the functions of these SNPs. Dual-luciferase assays indicated that the functional SNP is not rs1295686 but a haplotype consisting of three other SNPs: rs1295685, rs848, and rs847. Through chromosome conformation capture, it was found that the enhancer containing the three functional SNPs interacts with the promoter of TH2LCRR (T helper type 2 locus control region associated RNA), a recently identified long noncoding RNA. RNA-seq data analysis indicated that TH2LCRR expression is significantly increased in patients with asthma and is dependent on the genotype at this locus, indicating that TH2LCRR is a novel susceptibility gene for asthma and that these SNPs confer asthma risk by regulating TH2LCRR expression. By chromatin immunoprecipitation, the related transcription factors that bind in the region surrounding these three SNPs were identified, and their interactions were investigated by functional genomics approaches. Our effort identified a novel mechanism through which genetic variations at this locus could influence asthma susceptibility.

Identification of rs11615992 as a novel regulatory SNP for human P2RX7 by allele-specific expression.

P2RX7 (purinergic receptor P2X 7) is an important membrane ion channel and involved in multiple physiological processes. One non-synonymous SNP on P2RX7, rs3751143, had been proven to reduce ion channel function and further associated with multiple diseases. However, it was still unclear whether there were other cis-regulatory elements for P2RX7, which might further contribute to related diseases. Allele-specific expression (ASE) is a robust and sensitive approach to identify the potential functional region in human genome. In the current study, we measured ASE on rs3751143 in lung tissues and observed a consistent excess of A allele over C (P = 0.001), which indicated that SNP(s) in linkage disequilibrium (LD) could regulate P2RX7 expression. By analyzing the 1000 genomes project data for Chinese, one SNP locating ~ 5 kb away and downstream of P2RX7, rs11615992, was disclosed to be in strong LD with rs3751143. The dual-luciferase assay confirmed that rs11615992 could alter target gene expression in lung cell line. Through chromosome conformation capture, it was verified that the region surrounding rs11615992 could interact with P2RX7 promoter and effect as an enhancer. By chromatin immunoprecipitation, the related transcription factor POU2F1 (POU class 2 homeobox 1) was recognized to bind the region spanning rs11615992. Our work identified a novel long-distance cis-regulatory SNP for P2RX7, which might contribute to multiple diseases.

Allele-specific expression identified rs2509956 as a novel long-distance cis-regulatory SNP for SCGB1A1, an important gene for multiple pulmonary diseases.

SCGB1A1 (secretoglobin family 1A member 1) is an important protein for multiple pulmonary diseases, especially asthma, chronic obstructive pulmonary disease, and lung cancer. One single-nucleotide polymorphism (SNP) at 5'-untranslated region of SCGB1A1, rs3741240, has been suggested to be associated with reduced protein expression and further asthma susceptibility. However, it was still unclear whether there were other cis-regulatory elements for SCGB1A1 that might further contribute to pulmonary diseases. Allele-specific expression (ASE) is a novel approach to identify the functional region in human genome. In the present study, we measured ASE on rs3741240 in lung tissues and observed a consistent excess of G allele over A (P < 10-6), which indicated that this SNP or the one(s) in linkage disequilibrium (LD) could regulate SCGB1A1 expression. By analyzing 1000 Genomes Project data for Chinese, one SNP locating ~10.2 kb away and downstream of SCGB1A1, rs2509956, was identified to be in strong LD with rs3741240. Reporter gene assay confirmed that both SNPs could regulate gene expression in the lung cell. By chromosome conformation capture, it was verified that the region surrounding rs2509956 could interact with SCGB1A1 promoter region and act as an enhancer. Through chromatin immunoprecipitation and overexpression assay, the related transcription factor RELA (RELA proto-oncogene, NF-kB subunit) was recognized to bind the region spanning rs2509956. Our work identified a novel long-distance cis-regulatory SNP for SCGB1A1, which might contribute to multiple pulmonary diseases.

rs401681 and rs402710 confer lung cancer susceptibility by regulating TERT expression instead of CLPTM1L in East Asian populations.

Lung cancer is a common cancer in human and has presented significant genetic predisposition. Previous genome-wide association study observed that rs401681 within CLPTM1L (CLPTM1 like) was significantly associated with lung cancer. By analyzing 1000 genomes data for East Asian, we identified only one SNP in nearby region, rs402710, in high linkage disequilibrium with rs401681, which was also associated with lung cancer. However, the real causal SNP and mechanism for the association were still not clear. The following plasmid construction, mutagenesis, transient transfection and luciferase reading indicated that both SNPs could regulate gene expression in lung/bronchial epithelium Beas-2B cell line. By chromosome conformation capture, it was identified that the segment containing these two SNPs could interact with TERT (telomerase reverse transcriptase) promoter, thus indicating that these SNPs confer lung cancer risk by regulating TERT expression instead of CLPTM1L. Through chromatin immunoprecipitation, the transcript factors HNF4A (hepatocyte nuclear factor 4 alpha) and MAF1 (MAF1 homolog, negative regulator of RNA polymerase III) were recognized for the regions spanning rs401681 and rs402710, respectively. Our results uncovered a complete link between these two SNPs and lung cancer.

Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles: Sequential Embryo Transfer or Double-blastocyst Transfer?

OBJECTIVE: Both sequential embryo transfer (SeET) and double-blastocyst transfer (DBT) can serve as embryo transfer strategies for women with recurrent implantation failure (RIF). This study aims to compare the effects of SeET and DBT on pregnancy outcomes. METHODS: Totally, 261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective analysis. According to different embryo quality and transfer strategies, they were divided into four groups: group A, good-quality SeET (GQ-SeET, n=38 cycles); group B, poor-quality or mixed-quality SeET (PQ/MQ-SeET, n=31 cycles); group C, good-quality DBT (GQ-DBT, n=121 cycles); and group D, poor-quality or mixed-quality DBT (PQ/MQ-DBT, n=71 cycles). The main outcome, clinical pregnancy rate, was compared, and the generalized estimating equation (GEE) model was used to correct potential confounders that might impact pregnancy outcomes. RESULTS: GQ-DBT achieved a significantly higher clinical pregnancy rate (aOR 2.588, 95% CI 1.267-5.284, P=0.009) and live birth rate (aOR 3.082, 95% CI 1.482-6.412, P=0.003) than PQ/MQ-DBT. Similarly, the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET (aOR 4.047, 95% CI 1.218-13.450, P=0.023). The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT, and the same results were found between PQ/MQ-SeET and PQ/MQ-DBT. CONCLUSION: SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two groups. Better clinical pregnancy outcomes could be obtained by transferring good-quality embryos, no matter whether in SeET or DBT. Embryo quality plays a more important role in pregnancy outcomes for RIF patients.

[Application of half-dose depot long-acting triptorelin in postoperative adjuvant therapy for endometriosis].

OBJECTIVE: To evaluate the efficacy and adverse effects of half-dose depot long-acting triptorelin in the therapy of endometriosis. METHODS: The efficacy and adverse effects of routine-dose or half-dose triptorelin in postoperative endometriosis patients were prospectively observed. A total of 186 postoperative patients with moderate or severe endometriosis received an intramuscular injection of triptorelin every 28 days for 6 times. They were randomly divided into 3 groups, i.e. half-dose group (n = 99): 1.875 mg each time; "draw-back" group (n = 52): 3.75 mg first time, then 1.875 mg each time; and routine-dose group (n = 35): 3.75 mg each time. RESULTS: Amenorrhea was effectively induced in all patients after the second injection. There was no significant difference in the rate of serum E2 level at Day 28 of every injection below the upper limit of "estrogen threshold (110 - 146 pmol/L)" not stimulating ectopic endometrium proliferation among half-dose group, "draw-back" group and routine-dose group (99% vs 100% and 99.0%, P > 0.05), the percentage of E2 < 37 pmol/L in E2 < 110 pmol/L in half-dose group was significantly lower than that in "draw-back" and routine-dose groups after 2-5(th) injection (69% vs 79% and 85%, P < 0.01), but there was no significant difference after first half-dose and routine-dose injection (71% vs 73%, P > 0.05). No significant difference existed in the rate of pelvic pain relief during the first returning menstruation and the recurrence rate of endometriosis within 1 year postoperation among three groups (both P > 0.05). However, the incidences of menopausal syndrome and severe menopausal syndrome in half-dose group were significantly lower than those in "draw-back" and routine-dose groups (both P < 0.01). And the incompletion rate of six-time drug for severe menopause syndrome was also significantly lower (P < 0.05) while the completion rate of six-time drug use in half-dose group was significantly higher (P < 0.05). CONCLUSION: As a postoperative adjuvant, half-dose depot triptorelin therapy is efficacious for endometriosis. It reduces menopausal syndrome and treatment cost and enhances patient compliance.

[Relationship between mitochondrial cytochrome oxidase mRNA expression and maternal inheritance of asthma].

OBJECTIVE: To explore the relationship between the mRNA expression level of mitochondrial cytochrome oxidase and the maternal inheritance of asthma. METHODS: From January to December 2009, 220 asthma patients, 162 patient kins and 260 healthy subjects were recruited from Departments of Respiratory Critical Care Medicine and Pediatric Medicine at First Affiliated Hospital, Kunming Medical College. Lung function tests were performed and serum IgE level measured. The polymorphism of mitochondrial cytochrome oxidase gene polymorphisms was detected by direct sequencing. And the peripheral level of COX mRNA was measured by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: No significant difference existed in age, gender among 3 groups. For 3 groups, the first second forced expiratory volume (FEV1)/forced vital capacity (FVC) were 90.6 ± 6.2, 92.3 ± 2.3, 102.3 ± 2.3 and FEV1 percentage of expected value (FEV1%) were (82.9 ± 10.8)%, (94.8 ± 5.4)% and (98.3 ± 8.6)% respectively. The lung function was not significant difference among three groups. The mRNA expression level of mitochondrial cytochrome oxidase in peripheral blood were 0.357 ± 0.217, 0.637 ± 0.473 and 0.975 ± 0.260 in the asthma, kin and control groups respectively. No significant difference existed in the expression level of COX3 mRNA among 3 groups (F = 21.45, P = 0.012). The serum level of lgE was the highest for the asthma patients. And it was significantly higher in the asthma group than that in the control group ((283.6 ± 62.4) vs (52.3 ± 13.7) µg/L, F = 48.31, P < 0.05). Moreover, the serum level of IgE was significantly higher in the kin group than that in the control group ((116.4 ± 57.5) vs (52.3 ± 13.7) µg/L, F = 20.45, P < 0.05). However, there was a negative correlation between the mRNA expression level of mitochondrial cytochrome oxidase and the serum level of IgE among 3 groups. CONCLUSIONS: The down-regulated mRNA expressin of mitochondrial cytochrome oxidase may participate in allergic inflammation by regulating the level of IgE. And the maternal inheritance of asthma is in effect.

Single­nucleotide polymorphism rs6592645 confers asthma risk through regulating LRRC32 expression.

Asthma is a complex disease, often with evident genetic predisposition; for example, the single-nucleotide polymorphism (SNP) rs7130588 was significantly associated with asthma by genome-wide association study (GWAS). Analysis of 1000 Genomes Project data suggests that there is another SNP, rs6592645, in complete linkage disequilibrium with rs7130588 and should present the same signal in GWAS. However, the causal SNP and the mechanism for the association between rs7130588 and asthma remain to be elucidated. In the presents study, results from dual-luciferase assays indicated that the A/G alleles of rs7130588 failed to present significantly different reporter gene expression. By contrast, A allele of rs6592645 presented a significant increase in relative luciferase activity than G allele, thus suggesting that rs6592645 may be a causal SNP. Using chromosome conformation capture, the enhancer region containing rs6592645 was observed to interact with promoter region of leucine-rich repeat-containing 32 (LRRC32). Gene expression quantification suggested that LRRC32 expression is significantly increased in lung tissue of patients with asthma and is dependent on the genotype of this locus, thus verifying that LRRC32 may be involved in asthma onset and that rs6592645 can regulate LRRC32 expression. Through chromatin immunoprecipitation, transcription factor 3 (TCF3) was identified to bind to rs6592645 surrounding region and the interaction between TCF3 and rs6592645 surrounding region was investigated. Results from the present study may improve our understanding of the mechanism by which the genetic variation in this locus might influence asthma susceptibility.

Remote regulation of rs80245547 and rs72673891 mediated by transcription factors C-Jun and CREB1 affect GSTCD expression.

Chronic obstructive pulmonary disease (COPD), the third leading cause of death worldwide, is influenced by genetic factors. The genetic signal rs10516526 in the glutathione S-transferase C-terminal domain containing (GSTCD) gene is a highly significant and reproducible signal associated with lung function and COPD on chromosome 4q24. In this study, comprehensive bioinformatics analyses and experimental verifications were detailly implemented to explore the regulation mechanism of rs10516526 and GSTCD in COPD. The results suggested that low expression of GSTCD was associated with COPD (p = 0.010). And C-Jun and CREB1 transcription factors were found to be essential for the regulation of GSTCD by rs80245547 and rs72673891. Moreover, rs80245547T and rs72673891G had a stronger binding ability to these transcription factors, which may promote the allele-specific long-range enhancer-promoter interactions on GSTCD, thus making COPD less susceptible. Our study provides a new insight into the relationship between rs10516526, GSTCD, and COPD.

[Preliminary proteomic analysis of peripheral skeletal muscle atrophy in chronic obstructive pulmonary disease].

OBJECTIVE: To conduct a preliminary proteomic study of chronic obstructive pulmonary disease (COPD) with peripheral skeletal muscle atrophy. METHODS: A total of 16 COPD patients and 8 aged-matched persons because of bone fractures were recruited in First Hospital Affiliated to Kunming Medical College from February to July in 2010. According to body mass index, fat free mass index, quadriceps femoris perimeter and quadriceps femoris active contraction, they were divided into those with muscle atrophy (group A, n = 8) and those without (group B, n = 8). There were 6 males and 2 females with an average age of (70 ± 8) years in the group A and 5 males and 3 females with an average age of (74 ± 8) years in the group B. And the control group had 6 males and 2 females with an average age of (72 ± 6) years. All samples of total quadriceps protein were separated by two-dimensional gel electrophoresis. The abnormal protein points on electrophoresis were compared by PDQuest image software. And the differential protein expression was detected. Then the corresponding peptide quality fingerprint spectrum was analyzed by mass spectrometer. Finally the differential protein points were partially detected by a search of database. RESULTS: The two-dimensional gel electrophoresis yielded an excellent profile of resolution and repeatability. And 12 proteins likely to cause skeletal muscle atrophy in COPD were identified. Among them, 8 proteins belonged to structural proteins (actin alpha cardiac muscle isoform CRA_c, myosin regulatory light chain 2, ventricular/cardiac muscle isoform, myoglobin isoform myosin heavy polypeptide 7 cardiac muscle beta isoform CRA_c, actin, alpha skeletal muscle, actin alpha cardiac muscle isoform CRA_b, hemoglobin alpha 1 globin chain & myosin light chain 6B) and 4 proteins were of functional proteins (chain A, crystal structure of human enolase; troponin T, slow skeletal muscle isoform alpha, carbonate anhydrase, troponin T & slow skeletal muscle isoform b). CONCLUSIONS: COPD patients are often accompanied with obvious peripheral skeletal muscle atrophy. It may be caused by quantitative or qualitative changes of peripheral skeletal structural and functional proteins.

Relationship between polymorphisms in the 5' leader cistron, positions 16 and 27 of the adrenergic ß2 receptor gene and asthma in a Han population from southwest China.

BACKGROUND AND OBJECTIVE: Adrenergic ß2 receptors (ADRB2) play an important role in regulating pulmonary function. Many previous studies have investigated possible associations between polymorphisms in the ADRB2 gene and asthma, but have yielded conflicting results. Furthermore, little is known regarding the possible role of the Arg19Cys polymorphism in susceptibility to asthma among Chinese. METHODS: This case-control association study involved 238 patients with asthma and 265 healthy subjects from a Han population in southwest China. For all subjects, the 5' leader cistron Arg19Cys, Arg16Gly and Gln27Glu polymorphisms in the ADRB2 gene were characterized by direct sequencing. Genotype, allele and haplotype frequencies were determined. In addition, to evaluate the association between the ADRB2 polymorphisms and lung function, bronchodilator response to inhaled ß2 agonists (400 µg of albuterol) was assessed in the asthmatic patients. RESULTS: There were no significant differences in genotype or allele frequencies for the three ADRB2 polymorphisms between the two cohorts. The Arg19/Arg16/Gln27 haplotype was more frequent among asthmatic patients than control subjects (odds ratio 2.24, 95% confidence interval (CI): 1.05-4.73, P=0.04). Moreover, the Arg19/Cys19 genotype was associated with a lower FEV1% (mean difference -4.5, 95% CI: -12.5 to 3.6, P=0.02) and FEV1/FVC (mean difference 8.9, 95% CI: 8.5-9.4, P=0.01). The bronchodilator response to albuterol was also marginally lower in individuals who were homozygous for the Arg19 genotype (mean difference 4.2, 95% CI: 3.7-4.8, P=0.03). CONCLUSIONS: The Arg19/Cys19 genotype was an independent risk factor for lower FEV1% and FEV1/FVC. Asthmatic patients with the Arg19/Arg19 genotype showed decreased responsiveness to albuterol. Furthermore, the Arg19/Arg16/Gln27 haplotype may contribute to increased susceptibility to asthma in the Chinese population.

[Impact on outcome of frozen-thawed embryo transfer by reducing numbers of transferred embryos].

OBJECTIVE: To study the impact on pregnant outcome of reducing the number of embryos transferred from three to two in women at age less than 35 who received frozen-thawed embryo transfer (FET). METHODS: The analysis was performed on 90 FET cycles (77 infertile couples, less than 35 years old) with slow-freezing/rapid-thawing method, including 48 cycles with two embryos transferred and 42 cycles with three embryos transferred. The embryo survival rate, high quality embryo rate, clinical pregnancy rate, implantation rate and multiple pregnancies rate were analyzed. RESULTS: No significant differences in embryo survival rate (88.9% versus 88.1%), high quality embryo rate (89.6% versus 81.0%), clinical pregnancy rate (37.5% versus 42.9%), implantation rate (26.0% versus 18.3%) and multiple pregnancy rate (38.9% versus 16.7%) were observed between two and three embryos transferred group (all P > 0.05). However, there were 2 triple pregnancies in three embryos transferred group while none in two embryos transferred group. CONCLUSION: Reducing the number of high quality embryos transferred from three to two in women at age of less than 35 years old who received FET, could decrease the incidence of triple pregnancy and keep the similar clinical pregnancy rate.

Absence of association between SERPINE2 genetic polymorphisms and chronic obstructive pulmonary disease in Han Chinese: a case-control cohort study.

BACKGROUND: Recent studies have proposed that the serine protease inhibitor E2 (SERPINE2) was a novel susceptibility gene for chronic obstructive pulmonary disease (COPD) in Caucasians. However, this issue still remained controversial. Additional evidences from populations with different environments and/or genetic backgrounds, such as East Asian, would be helpful to elucidate the issue. METHODS: In this study, five proposed causal SNPs in SERPINE2 were genotyped in 327 COPD patients and 349 controls, all of which belonged to the Han population sampled from Southwest China. The frequency of each SNP was compared both individually and in combination between patients and controls. The potential relationship between these SNPs and severity of COPD was also investigated. RESULTS: Three SNPs (rs3795877, rs6747096, and rs3795879) showed complete linkage disequilibrium (r2 = 1), and the minor allele frequencies were 13.0% and 12.9% in case and control cohorts, respectively, with no significant difference observed (P = 0.96). We also failed to observe any significant correlation between these SNPs and COPD severity (P = 0.67). The other two SNPs (rs7579646 and rs840088) also presented a similar pattern. Moreover, four major haplotypes were observed in our sample but none showed a significant difference between case and control groups (P > 0.1). CONCLUSION: Our results failed to obtain the evidence that these SNPs in SERPINE2 contributed to the COPD susceptibility in the Han Chinese population.

[Combination of inhaled salmeterol/fluticasone and tiotropium in the treatment of chronic obstructive pulmonary disease: a randomised controlled trial].

OBJECTIVE: To observe the efficacy of combination therapy with inhaled salmeterol/fluticasone and tiotropium in reducing the frequency of acute episodes of symptom exacerbation and improving lung function and health status in chronic obstructive pulmonary disease (COPD). METHODS: One hundred and twenty-six patients (M/F: 92/34) with COPD were treated in a randomised, parallel-group, controlled study with salmeterol/fluticasone (50/250 microg) twice daily and tiotropium 18 microg once daily (n = 33, M/F: 23/10); salmeterol/fluticasone (50/250 microg) twice daily (n = 32, M/F: 24/8); or tiotropium 18 microg once daily (n = 32, M/F: 23/9) for 12 months. Patients in the blank control group (n = 29, M/F: 22/7) did not receive any inhaled anticholinergic drugs, long-acting beta(2) agonists or glucocorticoid therapy. Intention-to-treat analysis (n = 161) and per-protocol analysis (n = 126, age 45 - 71 years) were performed. RESULTS: Three active treatments significantly improved symptoms and health status. The use of rescue medication in the combination group [1 (0 - 7) time, 95% CI] was significantly decreased compared with those in the blank group [2 (0 - 29) times], salmeterol/fluticasone alone [2 (0 - 13) times], tiotropium alone [1 (0 - 11) time], F = 4.914, P < 0.01. The frequency of exacerbations in the combination group was (0.7 +/- 0.5) time, significantly lower than that in the blank group [(1.5 +/- 0.9) times], salmeterol/fluticasone alone [(1.2 +/- 0.6) times], and tiotropium alone [(1.1 +/- 0.5) times], F = 8.513, P < 0.01. The FEV(1) in the combination group after the trial was (1.19 +/- 0.03) L, significantly improved compared to that before treatment (1.09 +/- 0.04) L, a 9.5% increase, which was greater than the blank (0.9%), tiotropium alone (8.2%) and salmeterol/fluticasone alone (6.3%), t = -5.024 to -15.58, P < 0.01. CONCLUSION: Combination therapy with salmeterol/fluticasone and tiotropium leads to better control of symptoms and improved lung function, with no greater risk of side-effects, as compared to salmeterol/fluticasone or tiotropium alone in the treatment of COPD.

1H-NMR-based metabolic profiling of healthy individuals and high-resolution CT-classified phenotypes of COPD with treatment of tiotropium bromide.

BACKGROUND: Heterogeneity of COPD results in different therapeutic effects for different patients receiving the same treatment. COPD patients need to be individually treated according to their own characteristics. The purpose of this study was to explore the differences in different CT phenotypic COPD by molecular metabolites through the use of metabolomics. METHODS: According to the characteristics of CT imaging, 42 COPD patients were grouped into phenotype E (n=20) or phenotype M (n=24). Each COPD patient received tiotropium bromide powder for inhalation for a therapeutic period of 3 months. All subjects were assigned into phenotype E in pre-therapy (EB, n=20), phenotype E in post-therapy (EA, n=20), phenotype M in pre-therapy (MB, n=22), phenotype M in post-therapy (MA, n=22), or normal control (N, n=24). The method of metabolomics based on 1H nuclear magnetic resonance (1H-NMR) was used to compare the changes in serum metabolites between COPD patients and normal controls and between different phenotypes of COPD patients in pre- and post-therapy. RESULTS: Patients with COPD phenotype E responded better to tiotropium bromide than patients with COPD phenotype M in terms of pulmonary function and COPD assessment test scores. There were differences in metabolites in COPD patients vs normal control people. Differences were also observed between different COPD phenotypic patients receiving the treatment in comparison with those who did not receive treatment. The changes of metabolites involved lactate, phenylalanine, fructose, glycine, asparagine, citric acid, pyruvic acid, proline, acetone, ornithine, lipid, pyridoxine, maltose, betaine, lipoprotein, and so on. These identified metabolites covered the metabolic pathways of amino acids, carbohydrates, lipids, genetic materials, and vitamin. CONCLUSION: The efficacy of tiotropium bromide on COPD phenotype E is better than that of phenotype M. Metabolites detected by 1H-NMR metabolomics have potentialities of differentiation of COPD and healthy people, discrimination of different COPD phenotypes, and giving insight into the individualized treatment of COPD.

A functional SNP upstream of the ADRB2 gene is associated with COPD.

Background: Previous studies have suggested that ß2-adrenergic receptor (ADRB2) is associated with COPD. However, the role of genetic polymorphisms in ADRB2 on COPD has not been evaluated yet. Methods: In this study, SNaPshot genotyping, luciferase assay, chromatin immunoprecipitation and real-time polymerase chain reaction were adopted to investigate the association between ADRB2 genetic polymorphisms and COPD, comprehensively. Results: One single nucleotide polymorphism (rs12654778), located upstream of ADRB2, showed a significant association with COPD by the logistic regression analysis after adjusting for age, sex and smoking history (p=0.04) in 200 COPD patients and 222 controls from southwest Chinese population. Furthermore, the luciferase assay indicated that rs12654778-A allele reduced the relative promoter activity by ~26% compared with rs12654778-G allele (p=0.0034). The chromatin immunoprecipitation analysis demonstrated that rs12654778 modulated the binding affinity of transcription factor neurofibromin 1. In addition, a significantly reduced expression of ADRB2 in COPD patients was observed, compared with normal controls (p=0.017). Conclusion: Our findings suggest a previously unknown mechanism linking allele-specific effects of rs12654778 on ADRB2 expression to COPD onset, for the first time.

Relationship between COPD and polymorphisms of HOX-1 and mEPH in a Chinese population.

Recent studies have proposed that susceptibility to chronic obstructive pulmonary disease (COPD) might be related with the polymorphisms of some genes encoding antioxidant enzymes, such as heme oxygenase-1 (HOX-1) and microsomal epoxide hydrolase (mEPH). We examined these polymorphisms in 256 patients with COPD and 266 healthy smokers from Han population in Southwest China. The frequencies of each allele were compared both individually and in combination between patients and controls. Polymorphisms of HOX-1 gene could be grouped into three classes: S (or=32 repeat). The allele frequencies of class L and the genotypic frequencies of the group with L were significantly higher in COPD than in controls. Our findings also showed that the proportion of slow mEPH activity was significantly higher in COPD than in controls. Conversely, the proportion of fast mEPH activity was significantly lower in COPD. In combined analysis, the frequency of the individuals having at least one L allele in the HOX-1 gene promoter and slow or very slow activity genotype for mEPH was higher in COPD than in control. Genetic polymorphisms in HOX-1 and mEPH genes are associated with the development of COPD in Southwest China.

Heme oxygenase-1 polymorphism associated with severity of chronic obstructive pulmonary disease.

BACKGROUND: Recent studies have suggested that susceptibility to chronic obstructive pulmonary disease (COPD) might be related to the length polymorphism of (GT)(n) repeat in the 5'-flanking region of heme oxygenase-1 (HOX-1) gene. However, there has been no research about the relationship between the polymorphism of HOX-1 gene and severity of COPD. METHODS: The polymorphism of HOX-1 gene in 452 patients with COPD from Han population in Southwest China was analysed by fragment analysis. The frequencies of the HOX-1 genotype were compared with the stage of COPD of each patient. RESULTS: The HOX-1 genotypes were classified into two groups: group I were individuals with class L allele (the number of GT = 32 repeats), and group II were those without class L allele (the number of GT < 32 repeats). The genotypic frequency of the HOX-1 group I was significantly higher than group II in the very severe COPD patients (36.8% vs 22.4%, P < 0.01, OR = 2.0, 95% CI 1.3 - 3.1), while the genotypic frequency of the HOX-1 group II was lower in the mild COPD (16.0% vs 26.0%, P = 0.02, OR = 0.5, 95% CI 0.3 - 0.9). However, in moderate and severe stages COPD, there were similar genotypic frequencies between HOX-1 group I and group II. CONCLUSIONS: Genetic polymorphism in HOX-1 is associated with the severity of COPD in Southwest China. COPD patients with class L allele may be susceptible to develop very severe COPD. Conversely, the COPD patients without class L allele may be more easily stabilized on mild COPD.

Metabolic changes of different high-resolution computed tomography phenotypes of COPD after budesonide-formoterol treatment.

BACKGROUND: Metabolomics is the global unbiased analysis of all the small-molecule metabolites within a biological system. Metabolic profiling of different high-resolution computed tomography (HRCT) phenotypes of COPD patients before and after treatment may identify discriminatory metabolites that can serve as biomarkers and therapeutic agents. PATIENTS AND METHODS: 1H nuclear magnetic resonance spectroscopy (1H-NMR)-based metabolomics was performed on a discovery set of plasma samples from 50 patients with stable COPD. Patients were assigned into two groups on the basis of HRCT findings including phenotype E (n=22) and phenotype M (n=28). After budesonide-formoterol treatment (160/4.5 µg ×2 inhalations twice daily for 3 months), clinical characteristics and metabolites were then compared between phenotype E pretreatment and posttreatment, phenotype M pretreatment and posttreatment, phenotype E pretreatment and phenotype M pretreatment, and phenotype E posttreatment and phenotype M posttreatment. RESULTS: Inhaled budesonide-formoterol therapy for both phenotype E (emphysema without bronchial wall thickening) and phenotype M (emphysema with bronchial wall thickening) was effective. However, phenotype E and phenotype M were different in response to therapy. Patients with phenotype M in response to therapeutic effects were significantly greater compared with phenotype E. Certain metabolites were identified, which were closely related to the treatment and phenotype. Metabolic changes in phenotype E or phenotype M after treatment may be involved with adenosine diphosphate (ADP), guanosine, choline, malonate, tyrosine, glycine, proline, l-alanine, l-valine, l-threonine leucine, uridine, pyruvic acid, acetone and metabolism disturbance. Metabolic differences between phenotype E and phenotype M in pretreatment and posttreatment covered glycine, d-glucose, pyruvic acid, succinate, lactate, proline, l-valine and leucine. CONCLUSION: Bronchial wall thickening in COPD may be an indicator for predicting the better response to the treatment with bronchodilator and corticosteroid. The identification of metabolic alterations provides new insights into different HRCT phenotypes and therapeutic assessment of COPD.

Relationship between PPARα mRNA expression and mitochondrial respiratory function and ultrastructure of the skeletal muscle of patients with COPD.

Peripheral muscle dysfunction is an important complication in patients with chronic obstructive pulmonary disease (COPD). The objective of this study was to explore the relationship between the levels of peroxisome proliferator-activated receptor α (PPARα) mRNA expression and the respiratory function and ultrastructure of mitochondria in the vastus lateralis of patients with COPD. Vastus lateralis biopsies were performed on 14 patients with COPD and 6 control subjects with normal lung function. PPARα mRNA levels in the muscle tissue were detected by real-time PCR. A Clark oxygen electrode was used to assess mitochondrial respiratory function. Mitochondrial number, fractional area in skeletal muscle cross-sections, and Z-line width were observed via transmission electron microscopy. The PPARα mRNA expression was significantly lower in COPD patients with low body mass index (BMIL) than in both COPD patients with normal body mass index (BMIN) and controls. Mitochondrial respiratory function (assessed by respiratory control ratio) was impaired in COPD patients, particularly in BMIL. Compared with that in the control group, mitochondrial number and fractional area were lower in the BMIL group, but were maintained in the BMIN group. Further, the Z-line became narrow in the BMIL group. PPARα mRNA expression was positively related to mitochondrial respiratory function and volume density. In COPD patients with BMIN, mitochondria volume density was maintained, while respiratory function decreased, whereas both volume density and respiratory function decreased in COPD patients with BMIL. PPARα mRNA expression levels are associated with decreased mitochondrial respiratory function and volume density, which may contribute to muscle dysfunction in COPD patients.