Displaying publications 61 - 80 of 162 in total

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  1. Wong YC, Abd El Ghany M, Naeem R, Lee KW, Tan YC, Pain A, et al.
    Front Microbiol, 2016;7:1288.
    PMID: 27597847 DOI: 10.3389/fmicb.2016.01288
    Burkholderia cenocepacia infection often leads to fatal cepacia syndrome in cystic fibrosis patients. However, antibiotic therapy rarely results in complete eradication of the pathogen due to its intrinsic resistance to many clinically available antibiotics. Recent attention has turned to the identification of essential genes as the proteins encoded by these genes may serve as potential targets for development of novel antimicrobials. In this study, we utilized TraDIS (Transposon Directed Insertion-site Sequencing) as a genome-wide screening tool to facilitate the identification of B. cenocepacia genes essential for its growth and viability. A transposon mutant pool consisting of approximately 500,000 mutants was successfully constructed, with more than 400,000 unique transposon insertion sites identified by computational analysis of TraDIS datasets. The saturated library allowed for the identification of 383 genes that were predicted to be essential in B. cenocepacia. We extended the application of TraDIS to identify conditionally essential genes required for in vitro growth and revealed an additional repertoire of 439 genes to be crucial for B. cenocepacia growth under nutrient-depleted conditions. The library of B. cenocepacia mutants can subsequently be subjected to various biologically related conditions to facilitate the discovery of genes involved in niche adaptation as well as pathogenicity and virulence.
    Matched MeSH terms: Cystic Fibrosis
  2. Raja J, Ng CT, Sujau I, Chin KF, Sockalingam S
    Clin Exp Rheumatol, 2016 Sep-Oct;34 Suppl 100(5):115-121.
    PMID: 26843456
    OBJECTIVES: To evaluate the associations between objectively measured gastroesophageal involvement using high-resolution manometry and 24- hour impedance-pH study, and clinical presentations in systemic sclerosis (SSc) patients.
    METHODS: This cross-sectional study was conducted in University of Malaya Medical Centre (UMMC) with 31 consecutive SSc patients recruited into this study. Clinical symptoms of gastroesophageal involvement, high-resolution impedance-manometry and 24-hour impedance-pH monitoring were assessed. Their associations with serological features and other organ involvement were evaluated.
    RESULTS: Twenty-five (80.6%) patients had gastroesophageal reflux disease (GORD) symptoms, mainly heartburn (45.1%), regurgitation (32.2%) and dysphagia (29%). Using manometry, oesophageal dysmotility was detected in 24 (88.9%) patients, while hypotensive lower oesophageal sphincter (LOS) was observed in 17 (63%) patients. 21 (84%) patients had GORD based on pH study. Hypotensive LOS was significantly associated with presence of digital ulcers. The main gastroesophageal symptoms were absent in majority of the SSc patients including in those with severe gastroesophageal manifestations demonstrating failed peristalsis >75%, hypotensive LOS, Demeester score >200 and acid reflux >200 per day. Demeester score >200 is associated with severity of GORD symptoms. Demeester score >200 was also associated with restrictive lung pattern (p=0.001). Significant association between GORD severity (daily number of acid reflux episodes >200) and pulmonary fibrosis was seen (p=0.030).
    CONCLUSIONS: The presence and severity of gastroesophageal symptoms may not accurately reflect the seriousness of oesophageal involvement. GORD severity is associated with presence of restrictive lung pattern and pulmonary fibrosis. Oesophageal manometry and 24-hour pH study should be considered more frequently in the assessment of SSc patients.
    Matched MeSH terms: Pulmonary Fibrosis
  3. Leow SS, Bolsinger J, Pronczuk A, Hayes KC, Sambanthamurthi R
    Genes Nutr, 2016;11:29.
    PMID: 27795741
    BACKGROUND: The Nile rat (NR, Arvicanthis niloticus) is a model of carbohydrate-induced type 2 diabetes mellitus (T2DM) and the metabolic syndrome. A previous study found that palm fruit juice (PFJ) delayed or prevented diabetes and in some cases even reversed its early stages in young NRs. However, the molecular mechanisms by which PFJ exerts these anti-diabetic effects are unknown. In this study, the transcriptomic effects of PFJ were studied in young male NRs, using microarray gene expression analysis.

    METHODS: Three-week-old weanling NRs were fed either a high-carbohydrate diet (%En from carbohydrate/fat/protein = 70:10:20, 16.7 kJ/g; n = 8) or the same high-carbohydrate diet supplemented with PFJ (415 ml of 13,000-ppm gallic acid equivalent (GAE) for a final concentration of 5.4 g GAE per kg diet or 2.7 g per 2000 kcal; n = 8). Livers were obtained from these NRs for microarray gene expression analysis using Illumina MouseRef-8 Version 2 Expression BeadChips. Microarray data were analysed along with the physiological parameters of diabetes.

    RESULTS: Compared to the control group, 71 genes were up-regulated while 108 were down-regulated in the group supplemented with PFJ. Among hepatic genes up-regulated were apolipoproteins related to high-density lipoproteins (HDL) and genes involved in hepatic detoxification, while those down-regulated were related to insulin signalling and fibrosis.

    CONCLUSION: The results obtained suggest that the anti-diabetic effects of PFJ may be due to mechanisms other than an increase in insulin secretion.

    Matched MeSH terms: Fibrosis
  4. Takebe Y, Tsujigiwa H, Katase N, Siar CH, Takabatake K, Fujii M, et al.
    J Oral Pathol Med, 2017 Jan;46(1):67-75.
    PMID: 27327904 DOI: 10.1111/jop.12467
    BACKGROUND: Tumor parenchyma-stromal interactions affect the properties of tumors and their dynamics. Our group previously showed that secreted frizzled related protein (sFRP)-2 impairs bone formation and promotes bone invasion in ameloblastoma. However, the effects of the secreted growth factors CCN2, TGF-β, and BMP4 on stromal tissues in ameloblastoma remain unclear.

    MATERIALS AND RESULTS: Thirty-five paraffin-embedded ameloblastoma cases, ameloblastoma-derived cell lines (AM-1), and primary cultures of ameloblastoma stromal fibroblasts (ASF) were used. Immunohistochemistry, MTT assay, Western blotting, and RT-PCR were performed on these samples. Parenchyma-stromal CCN2 overexpression correlated significantly with fibrous-type stroma, but not with myxoid-type stroma, suggesting a role of CCN2 in fibrosis (P < 0.05). Recombinant CCN2 induction of enhanced ASF proliferation in AM-1 medium supports this view. Conversely, BMP4 and TGF-β were expressed in myxoid-type fibroblasts, but little expression was found in parenchyma. RANKL-positive and CD68-positive stromal cell populations were significantly greater in myxoid-type tumor areas than in fibrous-type tumor areas, while a higher Ki-67 labeling index was recorded in ameloblastoma with fibrous-type stroma. These data suggest that stromal properties influence bone resorption-related activities and growth rates, respectively.

    CONCLUSIONS: These results suggest that the effects of secreted growth factors are governed by ameloblastoma parenchyma-stromal interactions. CCN2 promotes fibrogenesis independent of TGF-β signaling. Absence of CCN2 expression is associated with a phenotypic switch to a myxoid-type microenvironment that is conducive for TGF-β/BMP4 signaling to promote osteoclastogenesis.

    Matched MeSH terms: Fibrosis
  5. Leung GK, Ying D, Mak CC, Chen XY, Xu W, Yeung KS, et al.
    Mol Genet Genomic Med, 2017 Jan;5(1):40-49.
    PMID: 28116329 DOI: 10.1002/mgg3.258
    Cystic fibrosis (CF) is a rare condition in Asians. Since 1985, only about 30 Chinese patients have been reported with molecular confirmation.
    Matched MeSH terms: Cystic Fibrosis; Cystic Fibrosis Transmembrane Conductance Regulator
  6. Teoh KH, Balraj S, Navarasi SR
    Med J Malaysia, 2017 02;72(1):68-70.
    PMID: 28255147 MyJurnal
    Intrapancreatic accessory spleen (IPAS) is a benign anomaly of splenic embryology and a rare cause of pancreatic pseudotumour. Here, we report a case of a 70-year-old Malay lady whose IPAS was discovered incidentally during her surveillance computed tomography for her underlying left lower lung fibrosis. Radiologically, the lesion mimicked a neuroendocrine pancreatic tumour and was only diagnosed pathologically as IPAS after surgery. In conclusion, recognising IPAS as a differential for enhancing pancreatic mass allows us to exhaust all non-invasive diagnostic means to diagnose this benign lesion. It will allow the patient to avoid unnecessary surgery and its accompanying complications.
    Matched MeSH terms: Pulmonary Fibrosis
  7. Lan YW, Theng SM, Huang TT, Choo KB, Chen CM, Kuo HP, et al.
    Stem Cells Transl Med, 2017 03;6(3):1006-1017.
    PMID: 28297588 DOI: 10.5966/sctm.2016-0054
    Mesenchymal stem cells (MSCs) are widely considered for treatment of pulmonary fibrosis based on the anti-inflammatory, antifibrotic, antiapoptotic, and regenerative properties of the cells. Recently, elevated levels of oncostatin M (OSM) have been reported in the bronchoalveolar lavage fluid of a pulmonary fibrosis animal model and in patients. In this work, we aimed to prolong engrafted MSC survival and to enhance the effectiveness of pulmonary fibrosis transplantation therapy by using OSM-preconditioned MSCs. OSM-preconditioned MSCs were shown to overexpress type 2 OSM receptor (gp130/OSMRβ) and exhibited high susceptibility to OSM, resulting in upregulation of the paracrine factor, hepatocyte growth factor (HGF). Moreover, OSM-preconditioned MSCs enhanced cell proliferation and migration, attenuated transforming growth factor-β1- or OSM-induced extracellular matrix production in MRC-5 fibroblasts through paracrine effects. In bleomycin-induced lung fibrotic mice, transplantation of OSM-preconditioned MSCs significantly improved pulmonary respiratory functions and downregulated expression of inflammatory factors and fibrotic factors in the lung tissues. Histopathologic examination indicated remarkable amelioration of the lung fibrosis. LacZ-tagged MSCs were detected in the lung tissues of the OSM-preconditioned MSC-treated mice 18 days after post-transplantation. Taken together, our data further demonstrated that HGF upregulation played an important role in mediating the therapeutic effects of transplanted OSM-preconditioned MSCs in alleviating lung fibrosis in the mice. Stem Cells Translational Medicine 2017;6:1006-1017.
    Matched MeSH terms: Pulmonary Fibrosis
  8. Chinigarzadeh A, Karim K, Muniandy S, Salleh N
    J Biochem Mol Toxicol, 2017 Apr;31(4).
    PMID: 27891704 DOI: 10.1002/jbt.21878
    We hypothesized that genistein could affect the chloride (Cl(-) ) and bicarbonate (HCO3(-) ) secretory mechanisms in uterus. Ovariectomized female rats were given estradiol or estradiol plus progesterone with 25, 50, or 100 mg/kg/day genistein. Following completion of the treatment, uterine fluid Cl(-) and HCO3(-) concentrations were determined by in vivo uterine perfusion. Uteri were subjected for molecular biological analysis (Western blot, qPCR, and immunohistochemistry) to detect levels of expression of Cystic Fibrosis transmembrane regulator (CFTR), Cl(-) /HCO3(-) exchanger (SLC26a6), Na(+) /HCO3(-) cotransporter (SLC4a4), and estrogen receptor (ER)-α and β. Coadministration of genistein resulted in decrease in Cl(-) and HCO3(-) concentrations and expression of CFTR, SLC26a6, SLC4a4, and ER-α and ER-β in the uteri of estradiol-treated rats. In estradiol plus progesterone-treated rats, a significant increase in the above parameters were observed following high-dose genistein treatment except for the SLC24a4 level. In conclusion, genistein-induced changes in the uterus could affect the reproductive processes that might result in infertility.
    Matched MeSH terms: Cystic Fibrosis Transmembrane Conductance Regulator/drug effects; Cystic Fibrosis Transmembrane Conductance Regulator/genetics
  9. Wen WX, Lee SY, Siang R, Koh RY
    Adv Ther, 2017 06;34(6):1245-1269.
    PMID: 28484954 DOI: 10.1007/s12325-017-0547-2
    Fibrosis is a potentially debilitating disease with high morbidity rates. It is estimated that half of all deaths that occur in the USA are attributed to fibrotic disorders. Fibrotic disorders are characterized primarily by disruption in the extracellular matrix deposition and breakdown equilibrium, leading to the accumulation of excessive amounts of extracellular matrix. Given the potentially high prevalence of fibrosis and the paucity of agents currently available for the treatment of this disease, there is an urgent need for the identification of drugs that can be utilized to treat the disease. Pentoxifylline is a methylxanthine derivative that is currently approved for the treatment of vascular diseases, in particular, claudication. Pentoxifylline has three main properties: improving the rheological properties of blood, anti-inflammatory, and antioxidative. Recently, the effectiveness of pentoxifylline in the treatment of fibrosis via attenuating and reversing fibrotic lesions has been demonstrated in several clinical trials and animal studies. As a result of the limited availability of antifibrotic agents in the long-term treatment of fibrosis that can attenuate and even reverse fibrotic lesions effectively, it would be of particular importance to consider the potential clinical utility of pentoxifylline in the treatment of fibrosis. Thus, this paper discusses the evolving roles of pentoxifylline in the treatment of different types of fibrosis.
    Matched MeSH terms: Fibrosis/drug therapy*
  10. Kua KP, Lee SWH
    Pharmacotherapy, 2017 Jun;37(6):755-769.
    PMID: 28423192 DOI: 10.1002/phar.1936
    BACKGROUND: Respiratory syncytial virus (RSV) is a common pathogen in infants with cystic fibrosis (CF). The use of palivizumab prophylaxis for RSV infection as the standard of care for infants with CF remains controversial.

    OBJECTIVE: To evaluate the efficacy of palivizumab in reducing the incidence of RSV hospitalization in children with CF who are younger than 2 years.

    METHODS: Four electronic databases (PubMed, Embase, CINAHL, and CENTRAL) were searched from inception until January 31, 2017, for clinical studies investigating the use of palivizumab in infants with CF aged less than 2 years. The primary outcome was hospitalization rate due to RSV infection. Secondary outcomes included hospitalization for respiratory illness, length of hospital stay, safety (adverse effects), and cost-effectiveness of palivizumab prophylaxis.

    RESULTS: The review included a total of 10 studies (six cohort studies, two before-and-after studies, one cross-sectional study, and one randomized controlled trial) involving 3891 patients with CF. Seven studies reported that palivizumab prophylaxis had a positive impact on the rate of RSV hospitalization. Five studies (n=3404) reported that palivizumab prophylaxis significantly reduced the rate of hospitalization due to RSV infection compared to no prophylaxis. One study (n=5) demonstrated patients with CF who received palivizumab had no RSV hospitalization. Another study showed infants with CF receiving palivizumab (n=117) had a lower risk of hospitalization for RSV infection compared with premature infants (gestational age < 35 completed weeks) who received palivizumab (n=4880).

    CONCLUSIONS: Evidence from the literature suggests that palivizumab may have a potential role in reducing RSV hospitalization in children aged less than 2 years with CF. Given the lack of overall data, additional research is warranted to better understand the efficacy and safety of prophylactic palivizumab in infants with CF.

    Matched MeSH terms: Cystic Fibrosis/drug therapy*; Cystic Fibrosis/epidemiology
  11. Giribabu N, Karim K, Kilari EK, Salleh N
    J Ethnopharmacol, 2017 Jun 09;205:123-137.
    PMID: 28483637 DOI: 10.1016/j.jep.2017.05.002
    ETHNOPHARMACOLOGICAL RELEVANCE: Phylanthus niruri has been used to treat ailments related to the urogenital organs. In this study, this herb was hypothesized to help to ameliorate kidney disease in diabetes mellitus (DM).

    AIMS: To investigate P. niruri leaves aqueous extract (PN) effects on kidney functions, histopathological changes and levels of oxidative stress, inflammation, fibrosis, apoptosis and proliferation in DM.

    METHODS: PN was orally administered to streptozotocin-nicotinamide-induced male diabetic rats for 28 days. At the end of the treatment, fasting blood glucose (FBG) and kidney functions were measured. Kidney somatic index, histopathological changes and levels of RAGE, Nrf2, oxidative stress markers (TBARS, SOD, CAT and GPx), inflammatory markers (NFkβ-p65, Ikk-β, TNF-α, IL-1β and IL-6), apoptosis markers (caspase-3, caspase-9 and Bax), fibrosis markers (TGF-β1, VEGF and FGF-1) and proliferative markers (PCNA and Ki-67) were determined by biochemical assays, qPCR, Western blotting, immunohistochemistry or immunofluorescence.

    RESULTS: Administration of PN helps to maintain near normal FBG, creatinine clearance (CCr), blood urea nitrogen (BUN), BUN/Cr ratio, serum electrolytes, uric acid and urine protein levels in DM. Decreased RAGE, TBARS and increased Nrf2, SOD-1, CAT and GPx-1 were observed in PN-treated diabetic rat kidneys. Expression of inflammatory, fibrosis and apoptosis markers in the kidney reduced but expression of proliferative markers increased following PN treatment. Lesser histopathological changes were observed in the kidney of PN-treated diabetic rats.

    CONCLUSION: PN helps to preserve near normal kidney function and prevents histopathological changes via ameliorating oxidative stress, inflammation, fibrosis and apoptosis while enhancing proliferation of the kidney in DM.

    Matched MeSH terms: Fibrosis
  12. De Blasio MJ, Ramalingam A, Cao AH, Prakoso D, Ye JM, Pickering R, et al.
    Eur J Pharmacol, 2017 Jul 15;807:12-20.
    PMID: 28438648 DOI: 10.1016/j.ejphar.2017.04.026
    Endoplasmic reticulum (ER) stress contributes to progression of diabetic nephropathy, which promotes end-stage renal failure in diabetic patients. This study was undertaken to investigate the actions of tempol and ramipril, pharmacological agents that target the consequences of NADPH oxidase, on diabetic nephropathy in a rat model of type 1 diabetes, with an emphasis on markers of ER stress. Male Sprague-Dawley rats were injected intravenously with a single bolus of streptozotocin (55mg/kg) to induce type 1 diabetes. An additional age-matched group of rats was administered with citrate vehicle as controls. After 4 weeks of untreated diabetes, rats received tempol (1.5mM/kg/day subcutaneously, n=8), ramipril (1mg/kg/day in drinking water, n=8) or remained untreated for an additional 4 weeks (n=7). After 8 weeks of diabetes in total, kidneys were collected for histological analysis, gene expression and protein abundance. Tempol and ramipril blunted diabetes-induced upregulation of NADPH oxidase isoforms (Nox4, Nox2, p47phox), accompanied by an amelioration of diabetes-induced glomerular injury (podocin, nephrin, Kim-1), tubulo-interstitial fibrosis (TGFβ1, TGFβ-R2, pSMAD3, α-SMA) and pro-inflammatory cytokines (TNFα, MCP-1, ANX-A1, FPR2) expression. In addition, the diabetes-induced renal ER stress, evidenced by increased expression of GRP-78 chaperone and stress-associated markers ATF4, TRB3, as well as XBP1s, phospho-p38 mitogen-activated protein kinase (MAPK) and 3-nitrotyrosination, were all attenuated by tempol and ramipril. These observations suggest that antioxidant approaches that blunt NADPH upregulation may attenuate diabetic nephropathy, at least in part by negatively regulating ER stress and inflammation, and hence ameliorating kidney damage.
    Matched MeSH terms: Fibrosis
  13. Veeraveedu PT, Sanada S, Okuda K, Fu HY, Matsuzaki T, Araki R, et al.
    Biochem Pharmacol, 2017 Aug 15;138:73-80.
    PMID: 28450225 DOI: 10.1016/j.bcp.2017.04.022
    BACKGROUND AND PURPOSE: ST2 is one of the interleukin (IL)-1 receptor family members comprising of membrane-bound (ST2L) and soluble (sST2) isoforms. Clinical trials have revealed that serum sST2 levels predict outcome in patient with myocardial infarction or chronic heart failure (HF). Meanwhile, we and others have reported that ablation of ST2 caused exaggerated cardiac remodeling in both ischemic and non-ischemic HF. Here, we tested whether IL-33, the ligand for ST2, protects myocardium against HF induced by mechanical overload using ligand specific knockout (IL-33(-/-)) mice.

    METHODS AND RESULTS: Transverse aortic constriction (TAC)/sham surgery were carried out in both IL-33 and WT-littermates. Echocardiographic measurements were performed at frequent interval during the study period. Heart was harvested for RNA and histological measurements. Following mechanical overload by TAC, myocardial mRNA expressions of Th1 cytokines, such as TNF-α were enhanced in IL-33(-/-) mice than in WT mice. After 8-weeks, IL-33(-/-) mice exhibited exacerbated left ventricular hypertrophy, increased chamber dilation, reduced fractional shortening, aggravated fibrosis, inflammation, and impaired survival compared with WT littermates. Accordingly, myocardial mRNA expressions of hypertrophic (c-Myc/BNP) molecular markers were also significantly enhanced in IL-33(-/-) mice than those in WT mice.

    CONCLUSIONS: We report for the first time that ablation of IL-33 directly and significantly leads to exacerbate cardiac remodeling with impaired cardiac function and survival upon mechanical stress. These data highlight the cardioprotective role of IL-33/ST2 system in the stressed myocardium and reveal a potential therapeutic role for IL-33 in non-ischemic HF.

    Matched MeSH terms: Fibrosis
  14. Chadda KR, Ahmad S, Valli H, den Uijl I, Al-Hadithi AB, Salvage SC, et al.
    Sci Rep, 2017 09 11;7(1):11070.
    PMID: 28894151 DOI: 10.1038/s41598-017-11210-3
    Long QT Syndrome 3 (LQTS3) arises from gain-of-function Nav1.5 mutations, prolonging action potential repolarisation and electrocardiographic (ECG) QT interval, associated with increased age-dependent risk for major arrhythmic events, and paradoxical responses to β-adrenergic agents. We investigated for independent and interacting effects of age and Scn5a+/ΔKPQ genotype in anaesthetised mice modelling LQTS3 on ECG phenotypes before and following β-agonist challenge, and upon fibrotic change. Prolonged ventricular recovery was independently associated with Scn5a+/ΔKPQ and age. Ventricular activation was prolonged in old Scn5a+/ΔKPQ mice (p = 0.03). We associated Scn5a+/ΔKPQ with increased atrial and ventricular fibrosis (both: p 
    Matched MeSH terms: Fibrosis
  15. Valli H, Ahmad S, Chadda KR, Al-Hadithi ABAK, Grace AA, Jeevaratnam K, et al.
    Mech Ageing Dev, 2017 Oct;167:30-45.
    PMID: 28919427 DOI: 10.1016/j.mad.2017.09.002
    INTRODUCTION: Ageing and several age-related chronic conditions including obesity, insulin resistance and hypertension are associated with mitochondrial dysfunction and represent independent risk factors for atrial fibrillation (AF).

    MATERIALS AND METHODS: Atrial arrhythmogenesis was investigated in Langendorff-perfused young (3-4 month) and aged (>12 month), wild type (WT) and peroxisome proliferator activated receptor-γ coactivator-1β deficient (Pgc-1β-/-) murine hearts modeling age-dependent chronic mitochondrial dysfunction during regular pacing and programmed electrical stimulation (PES).

    RESULTS AND DISCUSSION: The Pgc-1β-/- genotype was associated with a pro-arrhythmic phenotype progressing with age. Young and aged Pgc-1β-/- hearts showed compromised maximum action potential (AP) depolarization rates, (dV/dt)max, prolonged AP latencies reflecting slowed action potential (AP) conduction, similar effective refractory periods and baseline action potential durations (APD90) but shortened APD90 in APs in response to extrasystolic stimuli at short stimulation intervals. Electrical properties of APs triggering arrhythmia were similar in WT and Pgc-1β-/- hearts. Pgc-1β-/- hearts showed accelerated age-dependent fibrotic change relative to WT, with young Pgc-1β-/- hearts displaying similar fibrotic change as aged WT, and aged Pgc-1β-/- hearts the greatest fibrotic change. Mitochondrial deficits thus result in an arrhythmic substrate, through slowed AP conduction and altered repolarisation characteristics, arising from alterations in electrophysiological properties and accelerated structural change.

    Matched MeSH terms: Fibrosis/metabolism
  16. Sideek MA, Smith J, Menz C, Adams JRJ, Cowin AJ, Gibson MA
    Int J Mol Sci, 2017 Oct 09;18(10).
    PMID: 28991210 DOI: 10.3390/ijms18102114
    Latent transforming growth factor-β-1 binding protein-2 (LTBP-2) belongs to the LTBP-fibrillin superfamily of extracellular proteins. Unlike other LTBPs, LTBP-2 does not covalently bind transforming growth factor-β1 (TGF-β1) but appears to be implicated in the regulation of TGF-β1 bioactivity, although the mechanisms are largely unknown. In experiments originally designed to study the displacement of latent TGF-β1 complexes from matrix storage, we found that the addition of exogenous LTBP-2 to cultured human MSU-1.1 fibroblasts caused an increase in TGF-β1 levels in the medium. However, the TGF-β1 increase was due to an upregulation of TGF-β1 expression and secretion rather than a displacement of matrix-stored TGF-β1. The secreted TGF-β1 was mainly in an inactive form, and its concentration peaked around 15 h after addition of LTBP-2. Using a series of recombinant LTBP-2 fragments, the bioactivity was identified to a small region of LTBP-2 consisting of an 8-Cys motif flanked by four epidermal growth factor (EGF)-like repeats. The LTBP-2 stimulation of TGF-β expression involved the phosphorylation of both Akt and p38 mitogen-activated protein kinase (MAPK) signalling proteins, and specific inactivation of each protein individually blocked TGF-β1 increase. The search for the cell surface receptor mediating this LTBP-2 activity proved inconclusive. Inhibitory antibodies to integrins β1 and αVβ5 showed no reduction of LTBP-2 stimulation of TGF-β1. However, TGF-β1 upregulation was partially inhibited by anti-αVβ3 integrin antibodies, suggestive of a direct or indirect role for this integrin. Overall, the study indicates that LTBP-2 can directly upregulate cellular TGF-β1 expression and secretion by interaction with cells via a short central bioactive region. This may be significant in connective tissue disorders involving aberrant TGF-β1 signalling.
    Matched MeSH terms: Fibrosis/metabolism
  17. Yu EPK, Reinhold J, Yu H, Starks L, Uryga AK, Foote K, et al.
    Arterioscler Thromb Vasc Biol, 2017 12;37(12):2322-2332.
    PMID: 28970293 DOI: 10.1161/ATVBAHA.117.310042
    OBJECTIVE: Mitochondrial DNA (mtDNA) damage is present in murine and human atherosclerotic plaques. However, whether endogenous levels of mtDNA damage are sufficient to cause mitochondrial dysfunction and whether decreasing mtDNA damage and improving mitochondrial respiration affects plaque burden or composition are unclear. We examined mitochondrial respiration in human atherosclerotic plaques and whether augmenting mitochondrial respiration affects atherogenesis.

    APPROACH AND RESULTS: Human atherosclerotic plaques showed marked mitochondrial dysfunction, manifested as reduced mtDNA copy number and oxygen consumption rate in fibrous cap and core regions. Vascular smooth muscle cells derived from plaques showed impaired mitochondrial respiration, reduced complex I expression, and increased mitophagy, which was induced by oxidized low-density lipoprotein. Apolipoprotein E-deficient (ApoE-/-) mice showed decreased mtDNA integrity and mitochondrial respiration, associated with increased mitochondrial reactive oxygen species. To determine whether alleviating mtDNA damage and increasing mitochondrial respiration affects atherogenesis, we studied ApoE-/- mice overexpressing the mitochondrial helicase Twinkle (Tw+/ApoE-/-). Tw+/ApoE-/- mice showed increased mtDNA integrity, copy number, respiratory complex abundance, and respiration. Tw+/ApoE-/- mice had decreased necrotic core and increased fibrous cap areas, and Tw+/ApoE-/- bone marrow transplantation also reduced core areas. Twinkle increased vascular smooth muscle cell mtDNA integrity and respiration. Twinkle also promoted vascular smooth muscle cell proliferation and protected both vascular smooth muscle cells and macrophages from oxidative stress-induced apoptosis.

    CONCLUSIONS: Endogenous mtDNA damage in mouse and human atherosclerosis is associated with significantly reduced mitochondrial respiration. Reducing mtDNA damage and increasing mitochondrial respiration decrease necrotic core and increase fibrous cap areas independently of changes in reactive oxygen species and may be a promising therapeutic strategy in atherosclerosis.

    Matched MeSH terms: Fibrosis
  18. Hudu SA, Niazlin MT, Nordin SA, Saeed MI, Tan SS, Sekawi Z
    Iran J Immunol, 2017 Dec;14(4):281-292.
    PMID: 29276181 DOI: IJIv14i4A3
    BACKGROUND: Hepatitis viruses are non-cytopathic viruses that lead to the infection and pathogenesis of liver diseases as a result of immunologically mediated events.

    OBJECTIVE: To investigate the expression of human inflammatory cytokines in chronic hepatitis B patients according to the severity of the infection.

    METHODS: We recruited a total of 120 patients, 40 of whom from cirrhotic, 40 non-cirrhotic, and 40 acute flare chronic hepatitis B and 40 healthy controls. For all groups total cellular RNA was extracted from whole blood samples, genomic DNA was eliminated, and cDNA was synthesized using the RT2 first strand kit, as instructed by the manufacturer. The real-time profiler PCR array was performed on a master cycler ep realplex and the data were analyzed using an online data analysis software.

    RESULTS: Non-cirrhotic chronic hepatitis B patients were found to significantly upregulate interleukin 10 receptors that regulate the balance between T helpers 1 and 2. On the other hand, patients with cirrhosis were found to have significant upregulated interleukin 3 gene expression.

    CONCLUSION: Our finding suggests that upregulation of anti-inflammatory and downregulation of pro-inflammatory cytokines may play a role in the progression of non-cirrhotic chronic hepatitis B patients to cirrhotic and acute flare. However, a multi-center study with a larger sample size is needed to confirm our findings.

    Matched MeSH terms: Fibrosis/genetics; Fibrosis/immunology*
  19. Abdul Azih, M.N., Hin, H.S., Kori, A.N., Rahman, A.A., Chunn, K.Y.
    MyJurnal
    We report a 26-year old lady who presented with chronic cough and breathlessness associated with subtle
    TB symptoms for 1 year. Her CT thorax showed multiple cavitating pulmonary nodules with mediastinal and
    cervical lymphadenopathy. Cervical lymph node biopsy and CT-guided pulmonary biopsy at our centre
    confirmed the diagnosis of Hodgkin’s lymphoma with pulmonary infiltrations. She was successfully treated
    with ABVD regime but later developed life-threatening bleomycin-induced pulmonary fibrosis. Sadly, she
    succumbed to respiratory failure due to severe pneumonia with possibility of bleomycin-induced pulmonary
    fibrosis. Multiple cavitating pulmonary nodules secondary to lymphoma is rare and in TB endemic area, it
    may result in delayed diagnosis and treatment.
    Matched MeSH terms: Pulmonary Fibrosis
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