BCATc inhibitor 2 ameliorated mitochondrial dysfunction and apoptosis in oleic acid-induced non-alcoholic fatty liver disease model.

Nonalcoholic fatty liver disease (NAFLD) is a prevalent hepatic disease in the world. Disorders of branched chain amino acid (BCAA) metabolism is involved in various diseases. In this study, we aim to explore the role of BCAA metabolism in the development of NAFLD and the protective effect of BCATc Inhibitor 2, an inhibitor of cytosolic branched chain amino acid transaminase, against NAFLD as well as its underlying mechanism. It was found that oleic acid induced lipid accumulation and apoptosis in HepG2 and LO2 cells. Supplementation of BCAAs further aggravated oleic acid-induced lipid accumulation and apoptosis. In contrast, treatment of BCATc Inhibitor 2 ameliorated oleic acid-induced lipid accumulation and apoptosis. Molecularly, supplementation of BCAAs or treatment of BCATc Inhibitor 2 up-regulated or down-regulated the expression of SREBP1 and lipogenesis-related genes without affecting lipolysis-related genes. BCATc Inhibitor 2 maintained mitochondrial function by ameliorating oleic acid-induced mitochondrial ROS generation and mitochondrial membrane potential disruption. In addition, BCATc Inhibitor 2 treatment alleviated oleic acid-induced activation of JNK and AKT signaling pathway and Bcl2/Bax/Caspase axis. In conclusion, our results indicate BCAA metabolism is involved in NAFLD and BCATc Inhibitor 2 protects against oleic acid-induced lipid accumulation and apoptosis. These findings suggest that BCATc Inhibitor 2 is a promising candidate drug for the treatment of NAFLD.

Reference values of induced sputum cytology in healthy children in guangzhou, southern china.

OBJECTIVE: To establish normal reference values of induced sputum cytology in healthy children in southern China. METHODS: During a period from January 2010 to December 2011, a total of 580 healthy children (5-16 years of age) were approached. A total of 266 children (137 boys and 129 girls) participated in the study. Sputum induction was carried out by using 5% hypertonic saline. Cell types in the sputum were examined by using routine methods. RESULTS: Sputum induction was completed in 175 of the 266 subjects (65.79%), but 16 sputum samples were disqualified. The overall success rate was 59.77% (159/266). Macrophages and neutrophils were the predominant cell types: macrophages: median, 76.14%; interquartile range (IQR), 32.68%; and 2.5% to 97.5% percentile, 1.00% to 94.50%; neutrophils: median, 20.67%; IQR, 33.0%; and 2.5% to 97.5% percentile, 4.00% to 92.75%; eosinophils: median, 0.39%; IQR, 1.93%; and 2.5% to 97.5% percentile, 0.00% to 6.50%; and lymphocytes: median, 1.22%; IQR, 2.04%; and 2.5% to 97.5% percentile, 0.00% to 5.00%. The cell types did not differ among different age, gender, and passive smoking groups. Adverse events occurred in 4.4% (7/159) of the participants who completed the procedures but required no specific treatment to dissipate. Peak expiratory flow did not differ between those who completed the procedures compared with those who did not, suggesting that the procedure is safe and feasible in children. CONCLUSIONS: The current study represents the first attempt to develop normal reference values of induced sputum cytology in Chinese children, and could be used as a control for future studies.

[Preliminary establishment of cytological examination and the normal reference values for hypertonic saline solution-induced sputum of healthy children in Guangzhou].

OBJECTIVE: To establish the method of cytological examination and the normal reference values for hypertonic saline solution-induced sputum of healthy children (age range from 5 to 15 years) with physical examination in Guangzhou. METHOD: A total of 352 children, 5 to 15 years old, were enrolled from primary school and middle school in Guangzhou from January to December, 2010. All subjects completed a standardized questionnaire on the presence of respiratory, allergic symptoms and family history, the medical history and the physical examination was performed by doctors, lung function (forced expiratory volume at 1 s in predicted normal, FEV(1)%) was determined. There were 266 healthy children (137 males, 129 females) who were selected and undergone hypertonic saline solution induction of sputum, and cytological examination was performed. Hypertonic saline (5%) was nebulized and inhaled for 15 - 30 min. No expectoration within 30 min was defined as failure, and the procedure was terminated. The part of opaque and higher density sputum samples was detected by cytology. The proportion of neutrophils, lymphocytes, eosinophils, macrophages and monocytes was calculated. This study was approved by the institutional Ethics Review Committee of First Affiliated Hospital of Guangzhou Medical College. Informed consent was obtained from the legal guardians of all participants following a detailed description of the purpose and potential benefits of the study. RESULT: There were 175 subjects' induced sputum specimens (175/266, 65.8%), non-qualified sputum samples were obtained from 16 of the subjects. The proportions of median (IQR) of lymphocytes were 0.012 (0.020), 95%CI were ranged from 0.015 to 0.022; neutrophils 0.207 (0.330), 95%CI 0.266 - 0.356 macrophages 0.761 (0.327), 95%CI 0.607 - 0.699; eosinophils 0.004 (0.019), 95%CI 0.013 - 0.022. There were no significant differences in proportions of cytological findings of female or male, different age groups and second-hand smoking or not (all P > 0.05). The incidence of adverse event was 4.40% (7/159). CONCLUSION: The method and the preliminary data may be used for research, diagnosis and treatment of patients with chronic cough and airway inflammation.

[Clinical characteristics of bronchiolitis obliterans in pediatric patients].

OBJECTIVE: To analyze the clinical characteristics, image findings, laboratory examination, the therapeutic methods and clinical outcomes of bronchiolitis obliterans (BO) in pediatric patients. METHOD: Twenty-six pediatric patients with BO were reported. All data were collected from cases who were hospitalized in the Department of Pediatrics, First Affiliated Hospital of Guangzhou Medical College from June 1(st), 2009 to the April 30(th), 2011, and infectious agents, clinical manifestations, risk factors, changes in imageology, laboratory examination, therapeutic methods and treatment responses were analyzed. RESULT: The ranges of age at onset was 4.5 months-8 years in 26 cases (18 boys and 8 girls). The course of disease was (6.2 ± 3.5) months. The period of followed-up ranged from 2 to 24 months. The common clinical characteristics were persistent wheezing of different severity (26 cases, 100%), cough (24 cases, 92%), intolerance to exercise (22 cases, 85%), short of breath (21 cases, 81%), retraction (20 cases, 77%), wheezy phlegm (16 cases, 62%), keeping with crackles (10 cases, 38%), cyanosis around the mouth (3 cases, 12%) and no clubbed fingers (toes). In 18 cases the etiology was detected, mycoplasma (11 cases, 42%), respiratory syncytial virus (4 cases, 15%), parainfluenza virus (2 cases, 8%), influenza virus A (2 cases, 8%) and influenza virus B (2 cases, 8%), human bocavirus (HBoV) (1 case, 4%). There were 8 cases (31%) with combined infection. Chest X-ray in 10 cases indicated changes suggestive of bronchopneumonia (38%), in only 1 case there was an image of interstitial pneumonia disease (4%). All the patients were diagnosed by high-resolution computerized tomography (HRCT). All cases were demonstrated to have air retention, poor blood perfusion in lung, just like "Westemark sign" with HRCT. In 19 cases antineutrophil cytoplasmic antibody (ANCA) was determined and 10 patients (53%) were positive for P-ANCA, and 8 cases (42%) were positive for C-ANCA. All patients received oral corticosteroid and low doses azithromycin. In 13 cases (50%) the treatment effectively reduced the severity of disease and the frequency of cough and wheezing. The average number of days for symptom improvement was (7.1 ± 4.8) days. CONCLUSION: Respiratory infection plays an important role in BO in children. The chronic and persistent wheezing, cough, intolerance to exercises, short breath, retraction were the main clinical manifestations. But these symptoms are non-specific. Chest X-ray can not provide enough information for diagnosis. Classical "Westemark sign" with HRCT is an important sign. ANCA with a high positive rate (approximately 50%) suppose immuno-lesion in BO. Oral corticosteroid and methotrexate may relieve clinical symptoms.

[The level and clinical significance of Toll-like receptor 4 in children with severe sepsis].

OBJECTIVE: To study the clinical significance of Toll-like receptor 4 (TLR4) in children with severe sepsis. METHODS: A prospective control study was performed. All cases were enrolled from pediatric department of the First Affiliated Hospital of Guangzhou Medical College, and they were divided into severe sepsis group (14 patients) who were diagnosed to have severe sepsis or septic shock in intensive care unit (ICU), pneumonia group (10 cases) with diagnosis of bronchial pneumonia, and healthy control group (10 healthy children). Venous blood samples of 2 ml were collected at admission, the level of TLR4 was detected by flow cytometry .At the same time, the changes in serum interleukin (IL-6, IL-10 ) and tumor necrosis factor-α (TNF-α) levels were determined by enzyme linked immunoadsorbent assay (ELISA). RESULTS: In severe sepsis group, the contents of TLR4 [(71.56±15.32)%], IL-6 [(1.98±1.55) ng/L], IL-10 [(88.20±61.23) ng/L] and TNF-α [(104.08±85.36) ng/L] were significantly higher than those in pneumonia group [(50.07±26.36)%, (0.93±0.16) ng/L, (41.42±7.02) ng/L, (48.96±6.40) ng/L] and healthy control group [(39.43±17.43)%, (0.94±0.43) ng/L,(43.73±22.68) ng/L, ( 49.94± 18.47) ng/L, all P<0.05). But there was no significant difference in the contents of TLR4, IL-6, IL-10 and TNF-α between pneumonia group and healthy control group (all P>0.05). CONCLUSION: This study suggests that TLR4 might be critically involved in the development of sepsis, and changes in TLR4 expression are parallel with levels of proinflammatory cytokines, including IL-6, TNF-α, and IL-10. The combination of TLR4 and proinflammatory cytokines would serve as the predictive parameters in early diagnosis and severity evaluation of sepsis in children.

Folding and membrane insertion of amyloid-beta (25-35) peptide and its mutants: implications for aggregation and neurotoxicity.

The mechanisms of interfacial folding and membrane insertion of the Alzheimer's amyloid-beta fragment Abeta(25-35) and its less toxic mutant, N27A-Abeta(25-35) and more toxic mutant, M35A-Abeta(25-35), are investigated using replica-exchange molecular dynamics in an implicit water-membrane environment. This study simulates the processes of interfacial folding and membrane insertion in a spontaneous fashion to identify their general mechanisms. Abeta(25-35) and N27A-Abeta(25-35) peptides share similar mechanisms: the peptides are first located in the membrane hydrophilic region where their C-terminal residues form helical structures. The peptides attempt to insert themselves into the membrane hydrophobic region using the C-terminal or central hydrophobic residues. A small portion of peptides can successfully enter the membrane's hydrophobic core, led by their C-terminal residues, through the formation of continuous helical structures. No detectable amount of M35A-Abeta(25-35) peptides appeared to enter the membrane's hydrophobic core. The three studied peptides share a similar helical structure for their C-terminal five residues, and these residues mainly buried within the membrane's hydrophobic region. In contrast, their N-terminal properties are markedly different. With respect to the Abeta(25-35), the N27A-Abeta(25-35) forms a more structured helix and is buried deeper within the membrane, which may result in a lower degree of aggregation and a lower neurotoxicity; in contrast, the less structured and more water-exposed M35A-Abeta(25-35) is prone to aggregation and has a higher neurotoxicity. Understanding the mechanisms of Abeta peptide interfacial folding and membrane insertion will provide new insights into the mechanisms of neurodegradation and may give structure-based clues for rational drug design preventing amyloid associated diseases.