Mateusz Siedlinski

Lung Function Loss, Smoking, Vitamin C Intake, and Polymorphisms of the Glutamate-Cysteine Ligase Genes

RATIONALE Smoking-induced oxidative stress contributes to chronic obstructive pulmonary disease, a lung disease characterized by low lung function and increasing mortality worldwide. The counterbalance for this effect may be provided by, for example, increased intake of the antioxidant vitamin C or endogenously acting antioxidant enzymes like glutamate-cysteine ligase (GCL), which is responsible for glutathione biosynthesis. OBJECTIVES To investigate associations of functional polymorphisms in GCL subunits (GCLM and GCLC) with lung function level and its longitudinal course, with vitamin C and smoking habits as potential interactive factors. METHODS Two independent general population samples (Doetinchem, n = 1,152, and Vlagtwedde-Vlaardingen, n = 1,390) with multiple lung function (FEV(1), VC) measurements were genotyped for three polymorphisms (C[-129]T, C[-588]T, and a trinucleotide GAG repeat [TNR]) in the subunits of GCL. Genetic effects on lung function level and decline were estimated using linear regression and linear mixed effect models adjusted for confounders. Findings were further investigated for interactions with vitamin C intake in the Doetinchem cohort. MEASUREMENTS AND MAIN RESULTS GCLC polymorphisms were significantly associated with lower lung function levels in interaction with pack-years smoked in both cohorts. TNR variants in GCLC were associated with accelerated FEV(1) decline in both cohorts in interaction with pack-years. All significant effects were specifically present in subjects within the lowest tertile of vitamin C intake. CONCLUSIONS GCLC is a novel susceptibility gene for low level of lung function in two independent populations. We provide suggestive evidence that this occurs due to an interaction between GCLC polymorphisms, smoking, and low vitamin C intake, which all contribute to the oxidative burden.

Superoxide dismutases, lung function and bronchial responsiveness in a general population

Oxidative stress is an important causative factor in the onset and progression of smoking-related lung diseases, such as chronic obstructive pulmonary disease (COPD). Superoxide dismutases (SODs) can prevent an increase in oxidative burden. A total of 1,390 subjects from the prospective Vlagtwedde–Vlaardingen cohort were genotyped for two single nucleotide polymorphisms (SNPs) in SOD2 and four SNPs in SOD3, which were further analysed for associations with the presence of bronchial hyperresponsiveness (BHR; provocative concentration causing a 10% fall in the forced expiratory volume in one second (FEV1; PC10 ≤8 mg·mL−1 of histamine), COPD (defined as Global Initiative for Chronic Obstructive Lung Disease stage II or higher), lung function level and the longitudinal course of FEV1. The intronic C5774T SNP of SOD2 was significantly associated with the presence of COPD and BHR in the total population. The T/T genotype for this polymorphism and the Val/Val genotype for the SOD2 Ala16Val substitution were risk factors for BHR in individuals without COPD. The SOD3 Arg213Gly substitution was associated with slower FEV1 decline in never-smokers exclusively, and the SOD3 G(−4466)T SNP was associated with a lower vital capacity level. Both SOD2 polymorphisms are associated with bronchial hyperresponsiveness, a risk factor for chronic obstructive pulmonary disease, while SOD2 C5774T additionally confers a risk for chronic obstructive pulmonary disease in the total population. The current authors furthermore confirm previously reported associations of SOD3 single nucleotide polymorphisms with lung function in the general population.

Genetic variation in TIMP1 but not MMPs predict excess FEV1 decline in two general population-based cohorts

BackgroundAn imbalance in Matrix MetalloProteases (MMPs) and Tissue Inhibitors of MMPs (TIMPs) contributes to Chronic Obstructive Pulmonary Disease (COPD) development. Longitudinal studies investigating Single Nucleotide Polymorphisms (SNPs) in MMPs and TIMPs with respect to COPD development and lung function decline in the general population are lacking.MethodsWe genotyped SNPs in MMP1 (G-1607GG), MMP2 (-1306 C/T), MMP9 (3 tagging SNPs), MMP12 (A-82G and Asn357Ser) and TIMP1 (Phe124Phe and Ile158Ile) in 1390 Caucasians with multiple FEV1 measurements from a prospective cohort study in the general population. FEV1 decline was analyzed using linear mixed effect models adjusted for confounders. Analyses of the X-chromosomal TIMP1 gene were stratified according to sex. All significant associations were repeated in an independent general population cohort (n = 1152).ResultsMMP2 -1306 TT genotype carriers had excess FEV1 decline (-4.0 ml/yr, p = 0.03) compared to wild type carriers. TIMP1 Ile158Ile predicted significant excess FEV1 decline in both males and females. TIMP1 Phe124Phe predicted significant excess FEV1 decline in males only, which was replicated (p = 0.10) in the second cohort. The MMP2 and TIMP1 Ile158Ile associations were not replicated. Although power was limited, we did not find associations with COPD development.ConclusionsWe for the first time show that TIMP1 Phe124Phe contributes to excess FEV1 decline in two independent prospective cohorts, albeit not quite reaching conventional statistical significance in the replication cohort. SNPs in MMPs evidently do not contribute to FEV1 decline in the general population.

Genome-wide protein QTL mapping identifies human plasma kallikrein as a post-translational regulator of serum uPAR levels

The soluble cleaved urokinase plasminogen activator receptor (scuPAR) is a circulating protein detected in multiple diseases, including various cancers, cardiovascular disease, and kidney disease, where elevated levels of scuPAR have been associated with worsening prognosis and increased disease aggressiveness. We aimed to identify novel genetic and bio‐molecular mechanisms regulating scuPAR levels. Elevated serum scuPAR levels were identified in asthma (n=514) and chronic obstructive pulmonary disease (COPD; n=219) cohorts when compared to controls (n=96). In these cohorts, a genome‐wide association study of serum scuPAR levels identified a human plasma kallikrein gene (KLKB1) promoter polymorphism (rs4253238) associated with serum scuPAR levels in a control/asthma population (P=1.17 × 10–7), which was also observed in a COPD population (combined P=5.04 × 10–12). Using a fluorescent assay, we demonstrated that serum KLKB1 enzymatic activity was driven by rs4253238 and is inverse to scuPAR levels. Biochemical analysis identified that KLKB1 cleaves scuPAR and negates scuPARs effects on primary human bronchial epithelial cells (HBECs) in vitro. Chymotrypsin was used as a proproteolytic control, while basal HBECs were used as a control to define scuPAR‐driven effects. In summary, we reveal a novel post‐translational regulatory mechanism for scuPAR using a hypothesis‐free approach with implications for multiple human diseases.—Portelli, M. A., Siedlinski, M., Stewart, C. E., Postma, D. S., Nieuwenhuis, M. A., Vonk, J. M., Nurnberg, P., Altmuller, J., Moffatt, M. F., Wardlaw, A. J., Parker, S. G., Connolly, M. J., Koppelman, G. H., Sayers, I. Genome‐wide protein QTL mapping identifies human plasma kallikrein as a post‐translational regulator of serum uPAR levels. FASEB J. 28, 923–934 (2014). www.fasebj.org

ABCC1 polymorphisms contribute to level and decline of lung function in two population-based cohorts

Objective The ATP-binding cassette transporter ABCC1 [i.e. multidrug resistance-associated protein 1 (MRP1)] is a membrane-bound pump excreting a variety of xenobiotics from the cell, and thus ABCC1 may play an important role in smoking-related lung function loss and development of chronic obstructive pulmonary disease (COPD). We earlier showed that bronchial epithelium of COPD patients have lower ABCC1 expression than that of healthy controls, with even further decrements in more severe COPD stages. In line with these results, we now aimed to assess effects of ABCC1 single nucleotide polymorphisms (SNPs) on both the level and the longitudinal course of lung function in the general population. Methods All 51 prevalent (minor allele frequency >5%) and noncorrelated (r2<0.8) ABCC1 SNPs were analyzed in two independent, prospective, population-based cohorts, that is, Doetinchem (n = 1152) and Vlagtwedde–Vlaardingen (n = 1390) studies (three and seven median lung function measurements, respectively, per patient), using linear regression and linear mixed-effect models. Results SNPs rs4148382 and rs212093 in the 3′-ABCC1 region were significantly associated with a higher and lower forced expiratory volume in 1 s (FEV1), respectively, in both the cohorts. Another rs35621 SNP (intron 14) was significantly associated with a highly excessive FEV1 decline in both cohorts. All replicated associations were additionally confirmed by permutation testing. Conclusion This is the first study showing a significant relationship between ABCC1 SNPs and lung function in two independent cohorts. These SNPs are therefore putative candidates for studies aiming to prevent COPD and investigating pharmacogenetics in established COPD.

Dietary factors and lung function in the general population: wine and resveratrol intake

Wine intake is associated with a better lung function in the general population, yet the source of this effect is unknown. Resveratrol, a polyphenol in wine, has anti-inflammatory properties in the lung, its effects being partially mediated via induction of Sirtuin (SIRT)1 activity. We assessed the impact of wine and resveratrol intake, and SIRT1 single-nucleotide polymorphisms (SNPs) on lung function in the general population. Effects of red and white wine and resveratrol intake on forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC were analysed in the population-based Doetinchem cohort (n=3,224). Associations of four tagging SIRT1 SNPs with lung function were analysed in the Doetinchem (n=1,152) and Vlagtwedde–Vlaardingen (n=1,390) cohorts. Resveratrol intake was associated with higher FVC levels, and white wine intake with higher FEV1 levels and lower risk of airway obstruction. SIRT1 SNPs were not significantly associated with level or course of lung function, either directly or indirectly via wine or resveratrol intake. This study shows a positive association of resveratrol intake with lung function in the general population, confirms the previously reported positive association of white wine intake with higher levels of FEV1, and additionally shows an association with a higher FEV1/FVC ratio. These effects probably do not run via SNPs in SIRT1.

Nicotinic Acetylcholine Receptor Variants Are Related to Smoking Habits, but Not Directly to COPD

Genome-wide association studies identified single nucleotide polymorphisms (SNPs) in the nicotinic acetylcholine receptors (nAChRs) cluster as a risk factor for nicotine dependency and COPD. We investigated whether SNPs in the nAChR cluster are associated with smoking habits and lung function decline, and if these potential associations are independent of each other. The SNPs rs569207, rs1051730 and rs8034191 in the nAChR cluster were analyzed in the Vlagtwedde-Vlaardingen cohort (n = 1,390) that was followed for 25 years. We used GEE and LME models to analyze the associations of the SNPs with quitting or restarting smoking and with the annual FEV1 decline respectively. Individuals homozygote (CC) for rs569207 were more likely to quit smoking (OR (95%CI) = 1.58 (1.05–2.38)) compared to wild-type (TT) individuals. Individuals homozygote (TT) for rs1051730 were less likely to quit smoking (0.64 (0.42; 0.97)) compared to wild-type (CC) individuals. None of the SNPs was significantly associated with the annual FEV1 decline in smokers and ex-smokers. We show that SNPs in the nAChR region are associated with smoking habits such as quitting smoking, but have no significant effect on the annual FEV1 decline in smokers and ex-smokers, suggesting a potential role of these SNPs in COPD development via smoking habits rather than via direct effects on lung function.

No effects of EPHX1 polymorphisms on the level or change of FEV1 in the general population.

To the Editors: Chappell et al. 1 recently found that several single nucleotide polymorphisms (SNPs) in the glutamate cysteine ligase (catalytic subunit; GCLC) and epoxide hydrolase 1 (EPHX1) do not associate with the presence or severity of chronic obstructive pulmonary disease (COPD). We have previously shown in two independent population-based cohorts that the functional polymorphism rs17883901 and the trinucleotide GAG repeat in GCLC form unique genotype combinations that are associated with lower lung function in interaction with smoking 2. Chappell et al. 1 did not study the latter variation in GCLC, nor the interaction between SNPs and smoking in relation to COPD severity, which is of special interest given the in vivo role of GCLC. They additionally studied SNPs in EPHX1, including nonsynonymous SNPs (nsSNPs) Tyr113His and His139Arg that previously provided both positive and negative associations with COPD across studies and races 1, 3–7. We aimed to extend these findings by showing the effects of EPHX1 SNPs on the level and change of forced expiratory volume in one second (FEV1) in the general population, and additionally investigated whether EPHX1 SNPs smoking interactions are associated with both outcomes, …

Heme oxygenase 1 variations and lung function decline in smokers: proof of replication

We provide supportive evidence for a role of the promoter polymorphism (GT-repeat) in heme oxygenase 1 (HO-1) in relation to lung function loss over time. This observation has been made by Guenegou and colleagues in a Caucasian population, and a call for replication of these results in a larger and independent cohort was made.1 The relevance of HO-1 has been widely acknowledged.2 Chronic obstructive pulmonary disease (COPD)—often a consequence of abnormally accelerated lung function decline3—has been widely studied in relation to HO-1 promoter GT-repeat, using a …

MBL2 and fever during neutropenia in children with acute lymphoblastic leukaemia.

negative clone, is an important observation that we believe has not been reported previously. Clinical studies that compared conventional chemotherapy without or with FLT3 inhibitor have yielded conflicting outcomes (Levis et al, 2011; Ravandi et al, 2010; Serve et al, 2010). The timing of of FLT3 inhibitor administration in relation to chemotherapy is probably a critical factor (Levis et al, 2004), where prior administration may inhibit the effects of subsequent chemotherapy (Pratz & Levis, 2008) while treatment following chemotherapy may be ineffective due to high circulating FLT3-ligand (Sato et al, 2011). In this regard, our observation of a sustainable suppression of the FLT3 clone by Sorafenib alone is especially informative as it suggests that FLT3 inhibitor has a definite and enduring role in complementing concomitant chemotherapy given for the FLT3-ITD wild type clones. Whether the adverse natural course associated with FLT3-positive AML could be altered with this strategy is worth exploring.