scholarly journals Phenotype of asthmatics with increased airway S-nitrosoglutathione reductase activity

2014 ◽  
Vol 45 (1) ◽  
pp. 87-97 ◽  
Author(s):  
Nadzeya V. Marozkina ◽  
Xin-Qun Wang ◽  
Vitali Stsiapura ◽  
Anne Fitzpatrick ◽  
Silvia Carraro ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Smooth Muscle ◽  
Severe Asthma ◽  
Reductase Activity ◽  
Asthma Diagnosis ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Asthma Patients ◽  
Increased Activity ◽  
Smooth Muscle Relaxant

S-Nitrosoglutathione is an endogenous airway smooth muscle relaxant. Increased airway S-nitrosoglutathione breakdown occurs in some asthma patients. We asked whether patients with increased airway catabolism of this molecule had clinical features that distinguished them from other asthma patients.We measured S-nitrosoglutathione reductase expression and activity in bronchoscopy samples taken from 66 subjects in the Severe Asthma Research Program. We also analysed phenotype and genotype data taken from the program as a whole.Airway S-nitrosoglutathione reductase activity was increased in asthma patients (p=0.032). However, only a subpopulation was affected and this subpopulation was not defined by a “severe asthma” diagnosis. Subjects with increased activity were younger, had higher IgE and an earlier onset of symptoms. Consistent with a link between S-nitrosoglutathione biochemistry and atopy: 1) interleukin 13 increased S-nitrosoglutathione reductase expression and 2) subjects with an S-nitrosoglutathione reductase single nucleotide polymorphism previously associated with asthma had higher IgE than those without this single nucleotide polymorphism. Expression was higher in airway epithelium than in smooth muscle and was increased in regions of the asthmatic lung with decreased airflow.An early-onset, allergic phenotype characterises the asthma population with increased S-nitrosoglutathione reductase activity.

scholarly journals CRISPR-Mediated Single Nucleotide Polymorphism Modeling in Rats Reveals Insight Into Reduced Cardiovascular Risk Associated With Mediterranean G6PD Variant

Hypertension ◽  
2020 ◽  
Vol 76 (2) ◽  
pp. 523-532 ◽  
Author(s):  
Atsushi Kitagawa ◽  
Igor Kizub ◽  
Christina Jacob ◽  
Kevin Michael ◽  
Angelo D’Alessandro ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Smooth Muscle ◽  
Pentose Phosphate Pathway ◽  
High Fat Diet ◽  
Vascular Diseases ◽  
Pentose Phosphate ◽  
Nucleotide Polymorphism ◽  
High Fat ◽  
Single Nucleotide ◽  
The Mediterranean

Epidemiological studies suggest that individuals in the Mediterranean region with a loss-of-function, nonsynonymous single nucleotide polymorphism (S188F), in glucose-6-phosphate dehydrogenase ( G6pd ) are less susceptible to vascular diseases. However, this association has not yet been experimentally proven. Here, we set out to determine whether the Mediterranean mutation confers protection from vascular diseases and to discover the underlying protective mechanism. We generated a rat model with the Mediterranean single nucleotide polymorphism (G6PD S188F ) using CRISPR-Cas9 genome editing. In rats carrying the mutation, G6PD activity, but not expression, was reduced to 20% of wild-type (WT) littermates. Additionally, unbiased metabolomics analysis revealed that the pentose phosphate pathway and other ancillary metabolic pathways connected to the pentose phosphate pathway were reduced ( P <0.05) in the arteries of G6PD S188F versus WT rats. Intriguingly, G6PD S188F mutants, as compared with WT rats, developed less large arterial stiffness and hypertension evoked by high-fat diet and nitric oxide synthase inhibition with L-N G -nitroarginine methyl ester. Intravenous injection of a voltage-gated L-type Ca 2+ channel agonist (methyl 2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)phenyl]-1,4-dihydropyridine-3-carboxylate; Bay K8644) acutely increased blood pressure in WT but not in G6PD S188F rats. Finally, our results suggested that (1) lower resting membrane potential of smooth muscle caused by increased expression of K + channel proteins and (2) decreased voltage-gated Ca 2+ channel activity in smooth muscle contributed to reduced hypertension and arterial stiffness evoked by L-N G -nitroarginine methyl ester and high-fat diet to G6PD S188F mutants as compared with WT rats. In summary, a mutation resulting in the replacement of a single amino acid (S188F) in G6PD, the rate-limiting enzyme in the pentose phosphate pathway, ascribed properties to the vascular smooth muscle that shields the organism from risk factors associated with vascular diseases.

scholarly journals Duodenal cytochrome b (Cybrd1) ferric reductase functional studies in cells

Metallomics ◽  
2017 ◽  
Vol 9 (10) ◽  
pp. 1389-1393 ◽  
Author(s):  
F. Schlottmann ◽  
M. Vera-Aviles ◽  
G. O. Latunde-Dada
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Cytochrome B ◽  
Cho Cells ◽  
Reductase Activity ◽  
Ferric Reductase ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Functional Studies ◽  
Duodenal Cytochrome B ◽  
In Cells

A single nucleotide polymorphism (rs10455) in the last exon of the Dcytb gene in C282Y hemochromatosis subjects exhibited increased ferric reductase activity in transgenic CHO cells.

Abstract 221: A Single Nucleotide Polymorphism of p27 Kip1 Associated with Vein Graft Patency Regulates Proliferation of Cells Derived from the Outer, but not the Inner, Venous Wall

2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Richard D Kenagy ◽  
Shinsuke Kikuchi ◽  
Lihua Chen ◽  
Errol S Wijelath ◽  
Michael Sobel ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Smooth Muscle ◽  
Vein Graft ◽  
Graft Failure ◽  
Cellular Proliferation ◽  
Circular Muscle ◽  
Outer Wall ◽  
Vasa Vasorum ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide

Introduction: p27Kip1 is a cell-cycle inhibitor whose -838C>A single nucleotide polymorphism (SNP) accounts for ~40% of the risk of peripheral vein graft failure. Methods: To determine SNP function, we tested growth of cells derived from explants of the outer and inner wall of veins (cleavage through medial circular muscle yields outer wall with adventitia and some media and inner wall with intima and some media). Results: Growth of cells at passage 6 was measured over 3 days in response to 10 ng/ml PDGF-BB + 2% serum. Outer wall cells with the AA p27 SNP genotype grow slower than those with the CC genotype, but inner wall cells do not show a genotype-dependent response (Figure). Gene expression of quiescent outer and inner wall cells (5pairs) measured by microarray show that 2876 genes are differentially expressed (≥2 fold difference with P≤.05). While there is no difference in expression of traditional smooth muscle markers (smooth muscle α-actin, smooth muscle myosin heavy chain, smoothelin, SM22α, and calponin1), expression of the pericyte markers, NG2 and PDGFRβ, is significantly higher in outer wall cells (4.2 and 2.2 fold over inner wall cells; P<.02). We also found CD31 immunostaining of the endothelial cells of the vasa vasorum was restricted to the outer wall. Conclusion: These results support the functionality of the p27Kip1-838C>A SNP in cellular proliferation, but only in outer wall cells. Pericytes of the vasa vasorum or other progenitors in the outer wall may be involved, but further studies must address the identity of precursors of the outer wall cells that are associated with graft failure.

Abstract 144: A Single Nucleotide Polymorphism of p27 Kip1 Associated with Vein Graft Patency Regulates Expression of p27 Kip1 in Both Venous Adventitial Cells and Smooth Muscle Cells but Selectively Regulates Proliferation of Adventitial Cells

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Richard D Kenagy ◽  
Shinsuke Kikuchi ◽  
Lihua Chen ◽  
Errol S Wijelath ◽  
Alexander W Clowes ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphism ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vein Graft ◽  
Graft Failure ◽  
Cell Types ◽  
Nucleotide Polymorphism ◽  
Single Nucleotide ◽  
Adventitial Cells ◽  
P27 Kip1

Introduction: p27 Kip1 (p27) is a cell-cycle inhibitor whose -838C>A single nucleotide polymorphism (SNP) accounts for ~40% of the risk of peripheral vein graft failure. However, whether this SNP is functional has not been definitely established. Methods: To determine functionality, we investigated paired adventitial cells and smooth muscle cells (SMC) derived from fresh human saphenous veins (N≥7 lines per group). After growth arrest in 2% serum followed by stimulation with 10 ng/ml PDGF-BB, we measured p27 mRNA, p27 protein, and cell proliferation using qRT-PCR, Western blotting, and cell counts, respectively. Results: The SNP genotype was associated with 72 hour adventitial cell growth, but not SMC growth. Adventitial AA cells grew 33% slower than those with the CC genotype (Figure 1A, B, p=.004). We expected AA adventitial cells to produce more p27 mRNA, but paradoxically, p27 mRNA was lower in both cell types of the AA genotype (Figure 1C, D, P<.01). However, levels of p27 protein (a single ~27 kD band in both cell types) were ~2 fold higher in AA adventitial cells and SMCs compared to the CC cells at both 0 and 72 hours (Figure 1E, 72 hours; P<.001 for genotype; 0 h data not shown). Adventitial cells and SMCs made comparable amounts of p27 protein. Conclusion: The p27 Kip1 -838C>A SNP regulates levels of p27 in both venous adventitial cells and SMCs. There is an effect of genotype on the growth of adventitial cells, but not on SMCs. AA cells produce ~2 fold higher p27 protein than CC cells, despite AA cells having ~2 fold lower levels of p27 mRNA. These data demonstrate that the p27 SNP is functional, that different cell types within the vein wall respond uniquely to this genetic polymorphism, and suggest an important role in graft failure for the precursor of the cultured adventitial cell.

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