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Mutations in the liver glycogen phosphorylase (Pygl) gene are associated with the diagnosis of glycogen storage disease type VI (GSD‐VI). To understand the pathogenesis of GSD‐VI, we generated a mouse model with Pygl deficiency (Pygl−/−). Pygl−/− mice exhibit hepatomegaly, excessive hepatic glycogen accumulation, and low hepatic free glucose along with lower fasting blood glucose levels and elevated blood ketone bodies. Hepatic glycogen accumulation in Pygl−/− mice increases with age. Masson's trichrome and picrosirius red staining revealed minimal to mild collagen deposition in periportal, subcapsular, and/or perisinusoidal areas in the livers of old Pygl−/− mice (>40 weeks). Consistently, immunohistochemical analysis showed the number of cells positive for alpha smooth muscle actin (α‐SMA), a marker of activated hepatic stellate cells, was increased in the livers of old Pygl−/− mice compared with those of age‐matched wild‐type (WT) mice. Furthermore, old Pygl−/− mice had inflammatory infiltrates associated with hepatic vessels in their livers along with up‐regulated hepatic messenger RNA levels of C‐C chemokine ligand 5 (Ccl5/Rantes) and monocyte chemoattractant protein 1 (Mcp‐1), indicating inflammation, while age‐matched WT mice did not. Serum levels of aspartate aminotransferase and alanine aminotransferase were elevated in old Pygl−/− mice, indicating liver damage. Conclusion: Pygl deficiency results in progressive accumulation of hepatic glycogen with age and liver damage, inflammation, and collagen deposition, which can increase the risk of liver fibrosis. Collectively, the Pygl‐deficient mouse recapitulates clinical features in patients with GSD‐VI and provides a model to elucidate the mechanisms underlying hepatic complications associated with defective glycogen metabolism.

Glycogen storage disease type IX (GSD-IX) constitutes nearly a quarter of all GSDs. This ketotic form of GSD is caused by mutations in phosphorylase kinase (PhK), which is composed of four subunits (α, β, γ, δ). PhK is required for the activation of the liver isoform of glycogen phosphorylase (PYGL), which generates free glucose-1-phosphate monomers to be used as energy via cleavage of the α -(1,4) glycosidic linkages in glycogen chains. Mutations in any of the PhK subunits can negatively affect the regulatory and catalytic activity of PhK during glycogenolysis. To understand the pathogenesis of GSD-IX-beta, we characterized a newly created PHKB knockout (Phkb−/−) mouse model. In this study, we assessed fasting blood glucose and ketone levels, serum metabolite concentrations, glycogen phosphorylase activity, and gene expression of gluconeogenic genes and fibrotic genes. Phkb−/− mice displayed hepatomegaly with lower fasting blood glucose concentrations. Phkb−/− mice showed partial liver glycogen phosphorylase activity and increased sensitivity to pyruvate, indicative of partial glycogenolytic activity and upregulation of gluconeogenesis. Additionally, gene expression analysis demonstrated increased lipid metabolism in Phkb−/− mice. Gene expression analysis and liver histology in the livers of old Phkb−/− mice (>40 weeks) showed minimal profibrogenic features when analyzed with age-matched wild-type (WT) mice. Collectively, the Phkb−/− mouse recapitulates mild clinical features in patients with GSD-IX-beta. Metabolic and molecular analysis confirmed that Phkb−/− mice were capable of sustaining energy homeostasis during prolonged fasting by using partial glycogenolysis, increased gluconeogenesis, and potentially fatty acid oxidation in the liver.

Background Understanding the burden of disease is important to establish cost-effective treatment strategies and to allocate healthcare resources appropriately. However, little reliable information is available regarding the overall economic burden imposed by chronic obstructive pulmonary disease (COPD) in Korea. Methods This study is a multicenter observational research on the COPD burden in Korea. Total COPD costs were comprised of three categories: direct medical, direct non-medical, and indirect costs. For direct medical costs, institutional investigation was performed at 13 medical facilities mainly based on the claims data. For direct non-medical and indirect costs, site-based surveys were administered to the COPD patients during routine visits. Total costs were estimated using the COPD population defined in the recent report. Results The estimated total costs were approximately 1,245 million US dollar (1,408 billion Korean won). Direct medical costs comprised approximately 20% of the total estimated costs. Of these, formal medical costs held more than 80%. As direct non-medical costs, nursing costs made up the largest percentage (39%) of the total estimated costs. Costs for COPD-related loss of productivity formed four fifths of indirect costs, and accounted for up to 33% of the total costs. Conclusion This study shows for the first time the direct and indirect costs of COPD in Korea. The total costs were enormous, and the costs of nursing and lost productivity comprised approximately 70% of total costs. The results provide insight for an effective allocation of healthcare resources and to inform establishment of strategies to reduce national burden of COPD.

Glycogen storage disease type Ia (GSDIa) is an inherited metabolic disorder caused by mutations in the enzyme glucose-6-phosphatase-α (G6Pase-α). Affected individuals develop renal and liver complications, including the development of hepatocellular adenoma/carcinoma and kidney failure. The purpose of this study was to identify potential biomarkers of the evolution of the disease in GSDIa patients. To this end, we analyzed the expression of exosomal microRNAs (Exo-miRs) in the plasma exosomes of 45 patients aged 6 to 63 years. Plasma from age-matched normal individuals were used as controls. We found that the altered expression of several Exo-miRs correlates with the pathologic state of the patients and might help to monitor the progression of the disease and the development of late GSDIa-associated complications.

Glycogen storage disease type Ia (GSD-Ia), characterized by impaired glucose homeostasis and chronic risk of hepatocellular adenoma (HCA), is caused by a deficiency in glucose-6-phosphatase-α (G6Pase-α or G6PC) activity. In a previous 70–90 week-study, we showed that a recombinant adeno-associated virus (rAAV) vector-mediated gene transfer that restores more than 3% of wild-type hepatic G6Pase-α activity in G6pc−/− mice corrects hepatic G6Pase-α deficiency with no evidence of HCA. We now examine the minimal hepatic G6Pase-α activity required to confer therapeutic efficacy. We show that rAAV-treated G6pc−/− mice expressing 0.2% of wild-type hepatic G6Pase-α activity suffered from frequent hypoglycemic seizures at age 63–65 weeks but mice expressing 0.5–1.3% of wild-type hepatic G6Pase-α activity (AAV-LL mice) sustain 4–6 h of fast and grow normally to age 75–90 weeks. Despite marked increases in hepatic glycogen accumulation, the AAV-LL mice display no evidence of hepatic abnormalities, hepatic steatosis, or HCA. Interprandial glucose homeostasis is maintained by the G6Pase-α/glucose-6-phosphate transporter (G6PT) complex, and G6PT-mediated microsomal G6P uptake is the rate-limiting step in endogenous glucose production. We show that hepatic G6PT activity is increased in AAV-LL mice. These findings are encouraging for clinical studies of G6Pase-α gene-based therapy for GSD-Ia.

The neurotransmitter, 5-hydroxytryptamine, acts as an immunomodulator by stimulating the release of inflammatory cytokines and regulating the function of dendritic cells and monocytes. The 5-hydroxytryptamine receptor 4 ( HTR4) gene is located in a region previously linked to an increased risk of asthma and atopy. The aim of this study was to investigate the association between HTR4 and asthma. Thirty-two single nucleotide polymorphisms (SNP) in HTR4 were investigated by direct sequencing of 24 DNA samples from unrelated Korean subjects. The 32 genetic variants comprised 22 intronic SNP, two SNP in the 3′-untranslated region (exon 7) and eight SNP in the 3′-downstream region. Logistic regression analysis showed that two intronic polymorphisms were significantly associated with the risk of asthma. Two minor HTR4 alleles, + 142828G > A and + 122769G > A, occurred at significantly higher frequencies in the asthmatic group than in the healthy control group (49.59% vs 42.29%, P = 0.003, and 47.99% vs 40.35%, P = 0.008, respectively), and these differences remained significant after correction for multiple testing ( P = 0.05, dominant mode of inheritance; and P = 0.03, dominant mode, respectively). Haplotype analysis revealed three haplotype blocks. The frequency of haplotype 1 in block 2 was significantly higher in asthmatics ( P = 0.003, dominant mode), whereas the frequency of haplotype 4 in block 3 was significantly lower in asthmatics ( P = 0.0009, dominant mode). SNP and haplotypes of the HTR4 gene were associated with the asthma phenotype and genetic variation of HTR4 may affect susceptibility to the development of asthma. Associations between single nucleotide polymorphisms in the 5-hydroxytryptamine receptor 4 ( HTR4) gene and asthma were investigated. Two intronic polymorphisms were associated with the risk of asthma. Haplotype analysis also showed an association with asthma. Variations in the HTR4 gene may influence the development of asthma. [ABSTRACT FROM AUTHOR]

Glycogen storage disease type Ia (GSD-Ia) patients deficient in glucose-6-phosphatase-α (G6Pase-α or G6PC) manifest disturbed glucose homeostasis. We examined the efficacy of liver G6Pase-α delivery mediated by AAV-GPE, an adeno-associated virus (AAV) serotype 8 vector expressing human G6Pase-α directed by the human G6PC promoter/enhancer (GPE), and compared it to AAV-CBA, that directed murine G6Pase-α expression using a hybrid chicken β-actin (CBA) promoter/cytomegalovirus (CMV) enhancer. The AAV-GPE directed hepatic G6Pase-α expression in the infused G6pc−/− mice declined 12-fold from age 2 to 6 weeks but stabilized at wild-type levels from age 6 to 24 weeks. In contrast, the expression directed by AAV-CBA declined 95-fold over 24 weeks, demonstrating that the GPE is more effective in directing persistent in vivo hepatic transgene expression. We further show that the rapid decline in transgene expression directed by AAV-CBA results from an inflammatory immune response elicited by the AAV-CBA vector. The AAV-GPE-treated G6pc−/− mice exhibit normal levels of blood glucose, blood metabolites, hepatic glycogen, and hepatic fat. Moreover, the mice maintained normal blood glucose levels even after 6 hours of fasting. The complete normalization of hepatic G6Pase-α deficiency by the G6PC promoter/enhancer holds promise for the future of gene therapy in human GSD-Ia patients. [ABSTRACT FROM AUTHOR]

The article discusses the study which examines the effects of polymorphism on the transcription of interleukin 17 receptor B (IL-17RB) isoforms. The study used 654 asthmatics or 356 healthy control subjects who underwent screening for polymorphism in IL-17RB by single-base extension where B-cells were measured by reverse transcription polymerase chain reaction. IT shows that the activation of IL-17RB intensifies allergic-type inflammatory responses by inducing Jun kinase and protein kinase.

This article discusses the possible role of chitinase in regulating allergies in a mouse model exposed to diesel exhaust. The authors measured the expression of Ym1 and Ym2 mRNA in lung tissues by reverse transcription-polymerase chain reaction. They concluded that diesel exhaust particles induced Ym mRNA expression via a Th2 cell-biased response and airway hyperresponsiveness suggesting that chitinase may play an important role in responsiveness and airway inflammation and therefore may be involved in regulating allergic diseases.

The article presents a study to identify those factors that are associated with responsiveness to high-dose inhaled glucocorticoids (GCs) in patients with moderate-to-severe asthma. GCs, which are usually administered by inhalation, are potent inhibitors of inflammatory responses and are currently considered to be the standard therapeutic regimen for the treatment of persistent asthma. GC therapy reduces the number of infiltrating eosinophils and lymphocytes in the airways of asthmatic patients, and decreases the production and release of proinflammatory mediators and cytokines.

Study objectives: Extensive airway inflammation and excessive mucus production are implicated in deaths from asthma. High-resolution CT (HRCT) can be used to image both large and small airway abnormalities in asthmatics. The aims of this study were to clarify the distinction of IIRCT features between near-fatal asthma (NFA) and non-NFA, and to evaluate serial follow-up HRCT scans of patients with NFA. Patients and design: Abnormalities of the large airway (bronchial wall thickness) and small airways (prominence of centrilobular structures and air trapping) were measured semiquantitatively on HRCT scans of 24 non-NFA, 16 NFA, and 16 control subjects. In addition, these abnormalities were reevaluated after intensive and relatively long-term (> 6 months) treatment with inhaled corticosteroids. Results: Prominence of centrilobular structures was observed in 36% of mild asthma cases, in 70% of moderate-to-severe asthma cases, and in 100% of NFA cases. Prominence of centrilobular structures, but neither bronchial wall thickness nor the area of air trapping, was significantly increased in NFA, as compared with mild or moderate-to-severe asthma (p < 0.05). In the seven non-NFA and five NFA patients who underwent follow-up HRCT scans, only bronchial wall thickness was decreased significantly in the NFA cases (p < 0.05), while bronchial wall thickness and the prominence of centrilobular structures were significantly decreased in the non-NFA cases. These small airway abnormalities were partially reversible in the both groups. Residual prominence of centrilobular structures after long-term inhaled corticosteroid treatment was significantly higher in NFA than non-NFA patients. Conclusions: The results of our study indicate that extensive small airway abnormalities may be associated with NFA, and that these abnormalities are partially reversible after the successful control of asthma symptoms. [ABSTRACT FROM AUTHOR]

Cytokines, having central functions in immunological and inflammatory process, are always expected to play important roles in the pathogenesis of various diseases, such as asthma. Genetic polymorphisms of those cytokine and cytokine receptor genes are the focus of genetic association studies. In an effort to identify gene(s) whose variant(s) are involved in the development of asthma, we examined the genetic effects of 19 single nucleotide polymorphisms in eight cytokine and cytokine receptor genes, includingIL1A,IL1B,IL2,IL3,IL4,IL8,IL10, andIL5RA, on asthma and atopy. Nineteen single nucleotide polymorphisms in eight cytokine and cytokine receptor genes were genotyped using the single-base extension method in a Korean asthma cohort (n=723). Logistic regression and multiple regressions were used for statistical analyses controlling for smoking, age, and gender as covariables. Genetic association analysis of polymorphisms revealed that one exonic (exon 1),IL3+79T>C(Ser27Pro), showed significant association with the risk of asthma and atopy. The Pro allele had shown dominant and protective effects on development of asthma in nonatopic subjects (P=0.002) and also showed significant association with the risk of atopy in normal control subjects (P=0.007). This information about the genetic association of important genes with asthma might provide valuable insights into strategies for the pathogenesis of asthma and atopy. [ABSTRACT FROM AUTHOR]

Study objectives: Eosinophilic bronchitis (EB) presents as a chronic cough and sputum eosinophilia without airflow limitation or bronchial hyperreactivity. Its long-term clinical course remains unknown. This study evaluated how frequently EB recurs and whether it develops chronic airway obstruction. Design: This study was a prospective analysis. Methods: Cough severity, FEV1, provocative concentration of methacholine causing a 20% fall in FEV1, and sputum eosinophil percentages were serially measured in 36 subjects for up to 48 months. All subjects inhaled corticosteroids until cough subsided. Results: Five of the twenty four follow-up subjects (21%) had a recurrent episode of EB 4 to 6 months after disappearance of the first episode of EB (recurrent eosinophilic bronchitis). Progressive FEV1 reduction > 20% was observed in three of the subjects, including a subject with asthma developing at the ninth month. Nineteen subjects had no recurrence of cough (nonrecurrent eosinophilic bronchitis) and no progressive FEV1 reduction > 20%. However, sputum eosinophilia recurred between 4 months and 24 months in 10 subjects. Mean values of FEV1 at the ninth and 12th months of the study were significantly lower in the recurrent eosinophilic bronchitis group than in the nonrecurrent eosinophilic bronchitis group (p < 0.01). Conclusion: These results suggest that repeated episode of EB is associated with the development of chronic airflow obstruction, including asthma. [ABSTRACT FROM AUTHOR]

Background: Airway eosinophilia is frequently observed during acute exacerbation of ashtma. Interleukin-5 (IL-5) and eotaxin are directly involved in the airway eosinophilia found in persistent asthma. Interrelation between these cytokines is expected to occur in acute exacerbation of asthma. Thus, we evaluated the relevance of interaction between eotaxin and IL-5 in the airway inflammation of acute exacerbation. Methods: We measured the number of inflammatory cells and the amount of eotaxin and IL-5 in sputum from 22 healthy subjects, 21 asthmatics with acute exacerbation and 16 patients with mild persistent ashtma, and reassessed these values in 7 subjects with acute exacerbation after 7 days' treatment with systemic steroid (2 mg/kg/day). Sources of IL-5 and eotaxin were investigated by immunohistochemical staining of sputum cells of 4 cases from each group. Results: Both IL-5 and eotaxin levels were higher in patients with acute exacerbation of asthma than in patients with persistent asthma and normal subjects. IL-5 and eotaxin levels were significantly correlated with eosinophil percentages in mild persistent ashtma. Eotaxin staining was found mainly on macrophages and occasionally on eosinophils. Steroid treatment markedly decreased eosinophil percentages and IL-5 levels within 7 days but did not alter eotaxin levels. Conclusions: Both IL-5 and eotaxin are associated with acute exacerbation of asthma. IL-5 rather than eotaxin is effectively decreased by the inhibitory effect of steroid in acute exacerbation. [ABSTRACT FROM AUTHOR]

Endogenous exhaled nitric oxide (NO) is increased in asthma patients, especially in the exacerbated state. To evaluate the role of NO in airway mucosa of toluene diisocyanate (TDI)- induced asthma in relation to clinical and immunologic findings, 20 TDI-induced asthma patients were enrolled and classified into two groups: 9 newly diagnosed patients (group I) and 11 patients having persistent asthma symptoms for >5 years despite work withdrawal (group II). Immunohistocytochemistry was applied to compare the expression of endothelial constitutive NOS (c-NOS) and induced NOS (i-NOS) in airway mucosa of both groups. They were observed in four areas: epithelium (EP), smooth muscle (SM), vascular endothelium (VE), and mucous gland (MG). The intensity of expression was graded on a scale of one to four and mean values were presented from blind readings observed by two experts. Serum-specific immunoglobulin E (IgE) and immunoglobulin G (IgG) antibodies to TDI-human serum albumin conjugate were measured by enzyme-linked immunosorbent assay. e-NOS was found most fre- quently in VE (5/6 [83.3] versus 7/10 [70%]) followed by MG, EP, and SM in both groups. i-NOS was found most frequently in EP (7/9 [77.8%] versus 7/11 [63.6%]), followed by MG, VE, and SM in both groups. The intensities of i-NOS and c-NOS of MG were significantly higher in group I than in group II (p < 0.05) with no significant differences in other areas (p > 0.05, respectively). There were no significant correlations between i-NOS or c-NOS expression and exposure or asthma symptom duration (p > 0.05). No associations were found between i-NOS or c-NOS expression and the presence of specific IgE or IgG to TDI-human serum albumin conjugate (p > 0.05, respectively). In conclusion, i-NOS and c-NOS expressions were noted in EP, SM, VE, and MG in airway mucosa of TDI-induced asthma patients, which may contribute to airway inflammation. [ABSTRACT FROM AUTHOR]

We recently developed bimodal germline chimera production approaches by transfer of primordial germ cells (PGCs) or embryonic germ cells (EGCs) into embryos and by transplantation of spermatogonial stem cells (SSCs) or germline stem cells (GSCs) into adult testes. This study was undertaken to investigate the reversible developmental unipotency of chicken germ cells using our established germline chimera production systems. First, we transferred freshly isolated SSCs from adult testis or in vitro cultured GSCs into stage X and stage 14-16 embryos, and we found that these transferred SSCs/GSCs could migrate to the recipient embryonic gonads. Of the 527 embryos that received SSCs or GSCs, 135 yielded hatchlings. Of 17 sexually mature males (35.3%), six were confirmed as germline chimeras through testcross analysis resulting in an average germline transmission efficiency of 1.3%. Second, PGCs/EGCs, germ cells isolated from embryonic gonads were transplanted into adult testes. The EGC transplantation induced germline transmission, whereas the PGC transplantation did not. The germline transmission efficiency was 12.5 fold higher (16.3 vs 1.3%) in EGC transplantation into testis (EGCs to adult testis) than that in SSC/GSC transfer into embryos (testicular germ cells to embryo stage). In conclusion, chicken germ cells from different developmental stages can (de)differentiate into gametes even after the germ cell developmental clock is set back or ahead. Use of germ cell reversible unipotency might improve the efficiency of germ cell-mediated germline transmission. [ABSTRACT FROM AUTHOR]

Glucose-6-phosphatase-β (G6Pase-β or G6PC3) deficiency, also known as severe congenital neutropenia syndrome 4, is characterized not only by neutropenia but also by impaired neutrophil energy homeostasis and functionality. We now show the syndrome is also associated with macrophage dysfunction, with murine G6pc3-/- macrophages having impairments in their respiratory burst, Chemotaxis, calcium flux, and phagocytic activities. Consistent with a glucose-6-phosphate (G6P) metabolism deficiency, G6pc3-/- macrophages also have a lower glucose uptake and lower levels of G6P, lactate, and ATP than wild-type macrophages. Furthermore, the expression of NADPH oxidase subunits and membrane translocation of p47Phox are down-regulated, and G6pc3-/- macrophages exhibit repressed trafficking in vivo both during an inflammatory response and in pregnancy. During pregnancy, the absence of G6Pase-ß activity also leads to impaired energy homeostasis in the uterus and reduced fertility of G6pc3-/- mothers. Together these results show that immune deficiencies in this congenital neutropenia syndrome extend beyond neutrophil dysfunction. [ABSTRACT FROM AUTHOR]