Plasma free amino acid profiles evaluate risk of metabolic syndrome, diabetes, dyslipidemia, and hypertension in a large Asian population

Background

Recently, the association of plasma free amino acid (PFAA) profile and lifestyle-related diseases has been reported. However, few studies have been reported in large Asian populations, about the usefulness of PFAAs for evaluating disease risks. We examined the ability of PFAA profiles to evaluate lifestyle-related diseases in so far the largest Asian population.

Methods

We examined plasma concentrations of 19 amino acids in 8589 Japanese subjects, and determined the association with variables associated with obesity, blood glucose, lipid, and blood pressure. We also evaluated the PFAA indexes that reflect visceral fat obesity and insulin resistance. The contribution of single PFAA level and relevant PFAA indexes was also examined in the risk assessment of lifestyle-related diseases.

Results

Of the 19 amino acids, branched-chain amino acids and aromatic amino acids showed association with obesity and lipid variables. The PFAA index related to visceral fat obesity showed relatively higher correlation with variables than that of any PFAA. In the evaluation of lifestyle-related disease risks, the odds ratios of the PFAA index related to visceral fat obesity or insulin resistance with the diseases were higher than most of those of individual amino acid levels even after adjusting for potential confounding factors. The association pattern of the indexes and PFAA with each lifestyle-related disease was distinct.

Conclusions

We confirmed the usefulness of PFAA profiles and indexes as markers for evaluating the risks of lifestyle-related diseases, including diabetes mellitus, metabolic syndrome, dyslipidemia, and hypertension in a large Asian population.

Alteration in plasma free amino acid levels and its association with gout

Background

Studies on the association of plasma-free amino acids with gout are very limited and produced conflicting results. Therefore, we sought to explore and characterize the plasma-free amino acid (PFAA) profile in patients with gout and evaluate its association with the latter.

Methods

Data from a total of 819 subjects (including 34 patients with gout) undergoing an annual health examination program in Shimane, Japan were considered for this study. Venous blood samples were collected from the subjects and concentrations of 19 plasma amino acids were determined by high-performance liquid chromatography–electrospray ionization–mass spectrometry. Student’s t-test was applied for comparison of variables between patient and control groups. The relationships between the presence or absence of gout and individual amino acids were investigated by logistic regression analysis controlling for the effects of potential demographic confounders.

Results

Among 19 amino acids, the levels of 10 amino acids (alanine, glycine, isoleucine, leucine, methionine, phenylalanine, proline, serine, tryptophan, valine) differed significantly (P < .001 to .05) between the patient and control groups. Univariate logistic regression analysis revealed that plasma levels of alanine, isoleucine, leucine, phenylalanine, tryptophan and valine had significant positive associations (P < .005 to .05) whereas glycine and serine had significant inverse association (P < .05) with gout.

Conclusions

The observed significant changes in PFAA profiles may have important implications for improving our understanding of pathophysiology, diagnosis and prevention of gout. The findings of this study need further confirmation in future large-scale studies involving a larger number of patients with gout.

Porcine Amelogenin is Expressed from the X and Y Chromosomes

Amelogenin is the major enamel matrix component in developing teeth. In eutherian mammals, amelogenin is expressed from the X chromosome only, or from both the X and Y chromosomes. Two classes of porcine amelogenin cDNA clones have been characterized, but the chromosomal localization of the gene(s) encoding them is unknown. To determine if there are sex-based differences in the expression of porcine amelogenin, we paired PCR primers for exons 1a, 1b, 7a, and 7b, and amplified enamel organ-derived cDNA separately from porcine males and females. The results show that exons 1a/2a and 7a are always together and can be amplified from both males (XY) and females (XX). Exons 1b/2b and 7b are also always paired, but can be amplified only from females. We conclude that porcine amelogenin is expressed from separate genes on the X and Y chromosomes, and not, as previously proposed, from a single gene with two promoters.

[Immune System Reaction against Environmental Pollutants]

Environmental pollutants (such as diesel exhaust particles and silica) cause disorders ranging from bronchial asthma to malignant tumors. In recent years, it has been reported that some of the signaling pathways in which environmental contaminants act in vivo are associated with innate immunity. Innate immunity recognizes ligands and induces inflammation. Those ligands are pathogen-associated molecular patterns (PAMPs: e.g., lipopolysaccharide) and danger-associated molecular patterns (DAMPs: e.g., cholesterol crystallization or uric acid crystal). Activation of innate immunity stimulates the acquired immunity system. Therefore, innate immunity regulates the strength of the general immune system. Furthermore, crystal silica, which is an environmental pollutant, activates innate immunity as a ligand. Innate immunity involves the membrane-bound Toll-like receptors (TLR) and cytoplasm-localized nucleotide-binding oligomerization domain (NOD)-like receptors (NLR). We reported the innate immunity-system-related diseases such as Crohn's disease, Blau syndrome, myelogenous leukemia, and sarcoidosis. An inflammasome complex containing NLR has attracted attention owing to its correlation with the onset of several diseases. It is reported that the inflammasome activation is related to the development of lifestyle-related diseases such as myocardial infarction and fatty liver. It is also reported that the mechanism by which crystal silica and asbestos cause inflammation involves the inflammasome activation. Analyzing the genes of innate immunity contributes to the clarification of the mechanism of disease onset caused by environmental pollutants.

Secretory phospholipases A2 are secreted from ciliated cells and increase mucin and eicosanoid secretion from goblet cells

BACKGROUND

Secretory phospholipases A2 (sPLA2) initiate the biosynthesis of eicosanoids, are increased in the airways of people with severe asthma, and induce mucin hypersecretion. We used IL-13-transformed, highly enriched goblet cells and differentiated (ciliary cell-enriched) human bronchial epithelial cell culture to evaluate the relative contribution of ciliated and goblet cells to airway sPLA2 generation and response. We wished to determine the primary source(s) of sPLA2 and leukotrienes in human airway epithelial cells.

METHODS

Human bronchial epithelial cells from subjects without lung disease were differentiated to a ciliated-enriched or goblet-enriched cell phenotype. Synthesis of sPLA2, cysteinyl leukotrienes (cysLTs), and airway mucin messenger RNA and protein was measured by real-time-polymerase chain reaction and an enzyme-linked immunosorbent assay, and the localization of mucin and sPLA2 to specific cells types was confirmed by confocal microscopy.

RESULTS

sPLA2 group IIa, V, and X messenger RNA expression was increased in ciliated-enriched cells (P < .001) but not in goblet-enriched cells. sPLA2 were secreted from the apical (air) side of ciliated-enriched cells but not goblet-enriched cells (P < .001). Immunostaining of sPLA2 V was strongly positive in ciliated-enriched cells but not in goblet-enriched cells. sPLA2 released cysLTs from goblet-enriched cells but not from ciliated-enriched cells, and this result was greatest with sPLA2 V (P < .05). sPLA2 V increased goblet-enriched cell mucin secretion, which was inhibited by inhibitors of lipoxygenase or cyclooxygenase (P < .02).

CONCLUSIONS

sPLA2 are secreted from ciliated cells and appear to induce mucin and cysLT secretion from goblet cells, strongly suggesting that airway goblet cells are proinflammatory effector cells.

Bronchoscopy-Guided Cooled Radiofrequency Ablation as a Novel Intervention Therapy for Peripheral Lung Cancer

BACKGROUND

Our previous animal and preliminary human studies indicated that bronchoscopy-guided cooled radiofrequency ablation (RFA) for the lung is a safe and feasible procedure without major complications.

OBJECTIVES

The present study was performed to evaluate the safety, effectiveness and feasibility of computed tomography (CT)-guided bronchoscopy cooled RFA in patients with medically inoperable non-small-cell lung cancer (NSCLC).

METHODS

Patients with pathologically diagnosed NSCLC, who had no lymph node involvement or distant metastases (T1-2aN0M0) but were not surgical candidates because of comorbidities (e.g., synchronous multiple nodules, advanced age, cardiovascular disease, poor pulmonary function, etc.) were enrolled in the present study. The diagnosis and location between the nearest bronchus and target tumor were made by CT-guided bronchoscopy before the treatment. A total of 28 bronchoscopy-guided cooled RFA procedures were performed in 20 patients. After treatment, serial CT imaging was performed as follow-up.

RESULTS

Eleven lesions showed significant reductions in tumor size and 8 lesions showed stability, resulting in a local control rate of 82.6%. The median progression-free survival was 35 months (95% confidence interval: 22-45 months), and the 5-year overall survival was 61.5% (95% confidence interval: 36-87%). Three patients developed an acute ablation-related reaction (fever, chest pain) and required hospitalization but improved with conservative treatment. There were no other adverse events in the present study.

CONCLUSIONS

CT-guided bronchoscopy cooled RFA is applicable for only highly selected subjects; however, our trial may be an alternative strategy, especially for disease local control in medically inoperable patients with stage I NSCLC.

IL-33 stimulates CXCL8/IL-8 secretion in goblet cells but not normally differentiated airway cells

BACKGROUND

IL-13, a helper T cell type 2 (Th2) cytokine, transforms cultured airway epithelial cells to goblet cells, and this is not inhibited by corticosteroids. IL-33 stimulates Th2 cytokines and is highly expressed in airways of persons with asthma. The effect of IL-33 on goblet cell differentiation and cytokine secretion has not been described.

OBJECTIVE

We examined the effect of IL-33 on CXCL8/IL-8 secretion from goblet or normally differentiated human bronchial epithelial (NHBE) cells and signalling pathways associated with IL-33 activation in these cells.

METHODS

Normal human bronchial epithelial cells were grown to goblet or normally differentiated ciliated cell phenotype at air-liquid interface in the presence or absence of IL-13. After 14 days, differentiated cells were exposed to IL-33 for 24 h.

RESULTS

CXCL8/IL-8 secretion into the apical (air) side of the goblet cells was greater than from normally differentiated cells (P < 0.01), and IL-33 stimulated apical CXCL8/IL-8 release from goblet cells, but not from normally differentiated cells (P < 0.01). IL-33 increased ERK 1/2 phosphorylation in goblet cells (P < 0.05), and PD98059, a MAPK/ERK kinase inhibitor, attenuated IL-33-stimulated CXCL8/IL-8 secretion from goblet cells (P < 0.001). IL-13 induced ST2 mRNA (P < 0.02) and membrane-bound ST2 protein expression on the apical side surface of goblet cells compared with normally differentiated cells, and neutralization with anti-ST2R antibody attenuated IL-33-induced apical CXCL8/IL-8 secretion from goblet cells (P < 0.02).

CONCLUSIONS AND CLINICAL RELEVANCE

Goblet cells secrete CXCL8/IL-8, and this is increased by IL-33 through ST2R-ERK pathway, suggesting a mechanism for enhanced airway inflammation in the asthmatic airway with goblet cell metaplasia.