PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-18 (18)
 

Clipboard (0)
None

Select a Filter Below

Journals
more »
Year of Publication
Document Types
1.  Reduced Arylsulfatase B Activity in Leukocytes from Cystic Fibrosis Patients 
Pediatric pulmonology  2012;48(3):236-244.
Summary
The enzyme Arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase) removes 4-sulfate groups from chondroitin-4-sulfate and dermatan sulfate and is required for the degradation of these sulfated glycosaminoglycans (GAGs). Since these GAGs accumulate in patients with Cystic Fibrosis (CF), we investigated the activity of ARSB in leukocytes of patients with CF, to consider if reduced activity of ARSB might contribute to the pathophysiology of CF. Previous cell-based experiments had demonstrated that when the deficiency of the cystic fibrosis transmembrane regulator (CFTR) was corrected in bronchial epithelial cells, the ARSB activity increased significantly. De-identified, citrated blood samples were collected from 16 children with cystic fibrosis and 31 control subjects, seen in the Pediatric Clinic at Rush University Medical Center. Polymorphonuclear (PMN) and mononuclear cell (MC) populations were separated by density gradient, and blinded determinations of ARSB activity were performed using the exogenous substrate 4-methylumbilliferyl sulfate. Interleukin-6 was measured in the plasma samples by ELISA. ARSB activity was significantly less in the PMN and MC from the CF patients than controls (p<0.0001, unpaired t-test, two-tailed). Interleukin-6 levels in plasma were significantly greater in the CF population (p<0.001). Mean age, age range, and male:female ratio of CF patients and controls were similar, and no association of ARSB activity with age, gender, or CFTR genotype was evident. Since recombinant human ARSB is used successfully for replacement therapy in Mucopolysaccharidosis VI, it may be useful to restore ARSB activity to normal levels and increase degradation of sulfated GAGs in CF patients.
doi:10.1002/ppul.22567
PMCID: PMC3638799  PMID: 22550062
2.  Arylsulfatase B (N-Acetylgalactosamine-4-Sulfatase): Potential Role as a Biomarker in Prostate Cancer 
BACKGROUND
The enzyme Arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase) degrades chondroitin-4-sulfate (C4S) and is reduced in malignant colonic and mammary tissues, but has not previously been evaluated in prostate cancer.
METHODS
ARSB immunostaining was performed on two tissue microarrays (TMA) and analyzed by digital image analysis, generating ARSB H-scores for prevalence and intensity of epithelial, stromal, and combined epithelial and stromal immunostaining. Also, paired malignant and normal prostate tissues were analyzed for ARSB activity, C4S, total sulfated glycosaminoglycans, and versican content. The quantities of C4S and of the epidermal growth factor receptor that co-immunoprecipitated with versican were determined in the normal and malignant paired prostate tissues.
RESULTS
44 cases of prostate cancer were paired by age (± 5y), race, Gleason score (in order), and pathologic TNM score. The pairs differed by recurrence vs. non-recurrence of elevated PSA at 4 or more years. When TMA cores were analyzed for ARSB H-score, 18 of the 22 pairs had lower ARSB H-scores in the recurrent member of the pair, whereas higher initial PSA values were associated with recurrence in only 65% of the paired cases. In a second TMA, Gleason scores 6 and 7 were associated with higher ARSB H-scores than Gleason scores 8 and 9 for stroma, epithelium, and stroma and epithelium combined (p=0.052, p=0.015, p<0.0001, respectively) and were inversely correlated (r = −0.98, −0.97, and −0.99, respectively). In other paired normal and malignant prostate tissues, ARSB activity was significantly higher in the normal tissues, and C4S and versican values were lower (p<0.0001). C4S that co-immunoprecipitated with versican was greater in the malignant than in the normal tissue, whereas total EGFR that co-immunoprecipitated with versican was reduced.
DISCUSSION
Study findings suggest that ARSB may be useful as a prognostic biomarker in prostate cancer, and that the biological action of ARSB on chondroitin sulfate may impact upon versican’s effects in the tumor microenvironment.
doi:10.1038/pcan.2013.18
PMCID: PMC3763935  PMID: 23835622
arylsulfatase B; chondroitin sulfate; glycosaminoglycan; versican
3.  Impact of salt exposure on N-acetylgalactosamine-4-sulfatase (arylsulfatase B) activity, glycosaminoglycans, kininogen, and bradykinin 
Glycoconjugate journal  2013;30(7):10.1007/s10719-013-9468-8.
N -acetylgalactosamine-4-sulfatase (Arylsulfatase B; ARSB) is the enzyme that removes sulfate groups from the N-acetylgalactosamine-4-sulfate residue at the non-reducing end of chondroitin-4-sulfate (C4S) and dermatan sulfate (DS). Previous studies demonstrated reduction in cell-bound high molecular weight kininogen in normal rat kidney (NRK) epithelial cells when chondroitin-4-sulfate content was reduced following overexpression of ARSB activity, and chondroitinase ABC produced similar decline in cell-bound kininogen. Reduction in the cell-bound kininogen was associated with increase in secreted bradykinin. In this report, we extend the in vitro findings to in vivo models, and present findings in Dahl salt-sensitive (SS) rats exposed to high (SSH) and low salt (SSL) diets. In the renal tissue of the SSH rats, ARSB activity was significantly less than in the SSL rats, and chondroitin-4-sulfate and total sulfated glycosaminoglycan content were significantly greater. Disaccharide analysis confirmed marked increase in C4S disaccharides in the renal tissue of the SSH rats. In contrast, unsulfated, hyaluronan-derived disaccharides were increased in the rats on the low salt diet. In the SSH rats, with lower ARSB activity and higher C4S levels, cell-bound, high-molecular weight kininogen was greater and urinary bradykinin was lower. ARSB activity in renal tissue and NRK cells declined when exogenous chloride concentration was increased in vitro. The impact of high chloride exposure in vivo on ARSB, chondroitin-4-sulfation, and C4S-kininogen binding provides a mechanism that links dietary salt intake with bradykinin secretion and may be a factor in blood pressure regulation.
doi:10.1007/s10719-013-9468-8
PMCID: PMC3866634  PMID: 23385884
Bradykinin; Chondroitin; Disaccharide; Kininogen; Sulfatase; Sulfate
4.  Lactobacillus acidophilus Alleviates Platelet-Activating Factor-Induced Inflammatory Responses in Human Intestinal Epithelial Cells 
PLoS ONE  2013;8(10):e75664.
Probiotics have been used as alternative prevention and therapy modalities in intestinal inflammatory disorders including inflammatory bowel diseases (IBD) and necrotizing enterocolitis (NEC). Pathophysiology of IBD and NEC includes the production of diverse lipid mediators, including platelet-activating factor (PAF) that mediate inflammatory responses in the disease. PAF is known to activate NF-κB, however, the mechanisms of PAF-induced inflammation are not fully defined. We have recently described a novel PAF-triggered pathway of NF-κB activation and IL-8 production in intestinal epithelial cells (IECs), requiring the pivotal role of the adaptor protein Bcl10 and its interactions with CARMA3 and MALT1. The current studies examined the potential role of the probiotic Lactobacillus acidophilus in reversing the PAF-induced, Bcl10-dependent NF-κB activation and IL-8 production in IECs. PAF treatment (5 µM×24 h) of NCM460 and Caco-2 cells significantly increased nuclear p65 NF-κB levels and IL-8 secretion (2-3-fold, P<0.05), compared to control, which were blocked by pretreatment of the cells for 6 h with L. acidophilus (LA) or its culture supernatant (CS), followed by continued treatments with PAF for 24 h. LA-CS also attenuated PAF-induced increase in Bcl10 mRNA and protein levels and Bcl10 promoter activity. LA-CS did not alter PAF-induced interaction of Bcl10 with CARMA3, but attenuated Bcl10 interaction with MALT1 and also PAF-induced ubiquitination of IKKγ. Efficacy of bacteria-free CS of LA in counteracting PAF-induced inflammatory cascade suggests that soluble factor(s) in the CS of LA mediate these effects. These results define a novel mechanism by which probiotics counteract PAF-induced inflammation in IECs.
doi:10.1371/journal.pone.0075664
PMCID: PMC3794005  PMID: 24130731
5.  Platelet-activating factor-induced NF-κ B activation and IL-8 production in intestinal epithelial cells are Bcl10 dependent 
Inflammatory bowel diseases  2010;16(4):593-603.
Background
Platelet-activating factor (PAF), a potent pro-inflammatory phospholipid mediator, has been implicated in inducing intestinal inflammation in diseases such as inflammatory bowel disease (IBD) and necrotizing enterocolitis (NEC). However, its mechanisms of inducing inflammatory responses are not fully understood. Therefore, studies were designed to explore the mechanisms of PAF-induced inflammatory cascade in intestinal epithelial cells.
Methods
NF-κB activation was measured by luciferase assay and ELISA, and IL-8 production was determined by ELISA. Bcl10, CARMA3 and MALT1 mRNA and protein levels were assessed by real-time RT-PCR and Western blot, respectively. siRNA silencing of Bcl10 was used to examine its role in PAF-induced NF-κB activation and IL-8 production. Promoter region of Bcl10 gene was cloned by PCR method and promoter activity measured by luciferase assay.
Results
The adaptor protein Bcl10 appeared to play an important role in PAF-induced inflammatory pathway in human intestinal epithelial cells. Bcl10 was required for PAF-induced IκBα phosphorylation, NF-κB activation, and IL-8 production in NCM460, a cell line derived from normal human colon, and Caco-2, a transformed human intestinal cell line. PAF also stimulated Bcl10 interactions with CARMA3 and MALT1, and up-regulated Bcl10 expression in these cells via transcriptional regulation.
Conclusion
These findings highlight a novel PAF-induced inflammatory pathway in intestinal epithelial cells, requiring Bcl10 as a critical mediator and involving CARMA3/Bcl10/MALT1 interactions. The proinflammatory effects of PAF play prominent roles in the pathogenesis of IBD and this pathway may present important targets for intervention in chronic inflammatory diseases of the intestine.
doi:10.1002/ibd.21092
PMCID: PMC3740729  PMID: 19714753
IBD; inflammation; Caco-2; NCM460
6.  Prolongation of Carrageenan-induced Inflammation in Human Colonic Epithelial Cells by Activation of an NFκB – BCL10 Loop 
Biochimica et biophysica acta  2012;1822(8):1300-1307.
Carrageenan, a sulfated polysaccharide that is widely used as a food additive, induces inflammatory responses in animal models and human cells. The carrageenan-induced inflammatory cascades involve TLR4- and BCL10-dependent activation of NF-κB, leading to increased IL-8 production. Translocations involving BCL10 in the mucosa-associated lymphoid tissue (MALT) lymphomas are associated with constitutive activation of NF-κB. This report presents a mechanism by which carrageenan exposure leads to prolonged activation of both BCL10 and NF-κB in human colonic epithelial cells. Study findings demonstrate that nuclear RelA and RelB bind to an NF-κB binding motif in the BCL10 promoter in human colonic epithelial NCM460 and HT-29 cells. In vitro oligonucleotide binding assay, non-radioactive gel shift assay, and chromatin immunoprecipitation (ChIP) indicate binding of RelA and RelB to the BCL10 promoter. Prolonged inflammation follows activation of the BCL10-NFκB inflammatory loop in response to carrageenan, shown by increased BCL10, RelA, and IL-8 for 36 to 48 hours and increased RelB for 24 hours following withdrawal of carrageenan after 12 hours. In contrast, exposure to dextran sulfate sodium, which does not cause inflammation through TLR4 and BCL10 in the colonic epithelial cells, did not provoke prolonged activation of inflammation. The carrageenan-enhanced BCL10 promoter activity was blocked by caffeic acid phenethyl ester (CAPE) and MB-132 which inhibit NF-κB activation. These results indicate that NF-κB binding to the BCL10 promoter can lead to prolonged activation of the carrageenan-induced inflammatory cascade by a transcriptional mechanism involving an NF-κB – BCL10 loop.
doi:10.1016/j.bbadis.2012.05.001
PMCID: PMC3656608  PMID: 22579587
7.  CARRAGEENAN-INDUCED NFκB ACTIVATION DEPENDS ON DISTINCT PATHWAYS MEDIATED BY REACTIVE OXYGEN SPECIES AND HSP27 OR BY BCL10 
Biochimica et biophysica acta  2008;1780(0):973-982.
Carrageenans are highly sulfated polysaccharides that are widely used as food additives due to their ability to improve food texture. They are also widely recognized for their ability to induce inflammation in animal models of colitis. Recently, we reported that carrageenan (CGN) activated a pathway of innate immunity in human colonic epithelial cells mediated by Bcl10 (B-cell CLL/lymphoma 10). However, increases in phospho-IκBα and Interleukin-8 (IL-8) were not completely inhibited by silencing Bcl10, suggesting that CGN also influenced another mechanism, or mechanisms, of inflammation. In this report, we demonstrate that CGN increases production of reactive oxygen species (ROS) in human colonic epithelial cells. The combination of ROS quenching by the free radical scavenger Tempol and of Bcl10 silencing by siRNA completely inhibited the CGN-induced increases in nuclear NFκB (p65), phospho-IκBα, and secretion of IL-8. The CGN-induced increase in ROS was associated with declines in phosphorylation of MAPK 12 (p38γ), MAPK 13 (p38δ), and heat-shock protein (Hsp) 27. The CGN-induced decline in phospho-Hsp27 was reversed by co-administration of Tempol (100nM), but unaffected by silencing Bcl10. Since Hsp27 phosphorylation is inversely associated with phosphorylation of the IκBα kinase (IKK) signalosome, CGN exposure appears to affect the IKK signalosome by both the catalytic component, mediated by ROS-phospho-Hsp27, and the regulatory component, mediated by Bcl10 interaction with IKKγ (Nemo). Hence, the CGN-activated inflammatory cascades related to innate immunity and to generation of ROS may be integrated at the level of the IKK signalosome.
doi:10.1016/j.bbagen.2008.03.019
PMCID: PMC3698247  PMID: 18452717
Carrageenan; Reactive Oxygen Species (ROS); Bcl10 (B-cell CLL/lymphoma 10); Hsp27; MAPK; NFκB; IL-8; Colonic Epithelial Cells; sulfate assimilation pathway
8.  Carrageenan-Induced Colonic Inflammation Is Reduced in Bcl10 Null Mice and Increased in IL-10-Deficient Mice 
Mediators of Inflammation  2013;2013:397642.
The common food additive carrageenan is a known activator of inflammation in mammalian tissues and stimulates both the canonical and noncanonical pathways of NF-κB activation. Exposure to low concentrations of carrageenan (10 μg/mL in the water supply) has produced glucose intolerance, insulin resistance, and impaired insulin signaling in C57BL/6 mice. B-cell leukemia/lymphoma 10 (Bcl10) is a mediator of inflammatory signals from Toll-like receptor (TLR) 4 in myeloid and epithelial cells. Since the TLR4 signaling pathway is activated in diabetes and by carrageenan, we addressed systemic and intestinal inflammatory responses following carrageenan exposure in Bcl10 wild type, heterozygous, and null mice. Fecal calprotectin and circulating keratinocyte chemokine (KC), nuclear RelA and RelB, phospho(Thr559)-NF-κB-inducing kinase (NIK), and phospho(Ser36)-IκBα in the colonic epithelial cells were significantly less (P < 0.001) in the carrageenan-treated Bcl10 null mice than in controls. IL-10-deficient mice exposed to carrageenan in a germ-free environment showed an increase in activation of the canonical pathway of NF-κB (RelA) activation, but without increase in RelB or phospho-Bcl10, and exogenous IL-10 inhibited only the canonical pathway of NF-κB activation in cultured colonic cells. These findings demonstrate a Bcl10 requirement for maximum development of carrageenan-induced inflammation and lack of complete suppression by IL-10 of carrageenan-induced inflammation.
doi:10.1155/2013/397642
PMCID: PMC3677668  PMID: 23766559
9.  Exposure to common food additive carrageenan leads to reduced sulfatase activity and increase in sulfated glycosaminoglycans in human epithelial cells 
Biochimie  2012;94(6):1309-1316.
The commonly used food additive carrageenan, including lambda (λ), kappa (κ) and iota (ι) forms, is composed of galactose disaccharides linked in alpha-1,3 and beta-1,4 glycosidic bonds with up to three sulfate groups per disaccharide residue. Carrageenan closely resembles the endogenous galactose or N-acetylgalactosamine-containing glycosaminoglycans (GAGs), chondroitin sulfate (CS), dermatan sulfate (DS), and keratan sulfate. However, these GAGs have beta-1,3 and beta-1,4 glycosidic bonds, in contrast to the unusual alpha-1,3 glycosidic bond in carrageenan. Since sulfatase activity is inhibited by sulfate, and carrageenan is so highly sulfated, we tested the effect of carrageenan exposure on sulfatase activity in human intestinal and mammary epithelial cell lines and found that carrageenan exposure significantly reduced the activity of sulfatases, including N-acetylgalactosamine-4-sulfatase, galactose-6-sulfatase, iduronate sulfatase, steroid sulfatase, arylsulfatase A, SULF-1,2, and heparan sulfamidase. Consistent with the inhibition of sulfatase activity, following exposure to carrageenan, GAG content increased significantly and showed marked differences in disaccharide composition. Specific changes in CS disaccharides included increases in di-sulfated disaccharide components of CSD (2S6S) and CS-E (4S6S), with declines in CS-A (4S) and CS-C (6S). Specific changes in heparin-heparan sulfate disaccharides included increases in 6S disaccharides, as well as increases in NS and 2S6S disaccharides. Study results suggest that carrageenan inhibition of sulfatase activity leads to re-distribution of the cellular GAG composition with increase in di-sulfated CS and with potential consequences for cell structure and function.
doi:10.1016/j.biochi.2012.02.031
PMCID: PMC3495619  PMID: 22410212
Sulfatase; Carrageenan; Glycosaminoglycan; Disaccharide; Heparin; Chondroitin
10.  Hypoxia Reduces Arylsulfatase B Activity and Silencing Arylsulfatase B Replicates and Mediates the Effects of Hypoxia 
PLoS ONE  2012;7(3):e33250.
This report presents evidence of 1) a role for arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase) in mediating intracellular oxygen signaling; 2) replication between the effects of ARSB silencing and hypoxia on sulfated glycosaminoglycan content, cellular redox status, and expression of hypoxia-associated genes; and 3) a mechanism whereby changes in chondroitin-4-sulfation that follow either hypoxia or ARSB silencing can induce transcriptional changes through galectin-3. ARSB removes 4-sulfate groups from the non-reducing end of chondroitin-4-sulfate and dermatan sulfate and is required for their degradation. For activity, ARSB requires modification of a critical cysteine residue by the formylglycine generating enzyme and by molecular oxygen. When primary human bronchial and human colonic epithelial cells were exposed to 10% O2×1 h, ARSB activity declined by ∼41% and ∼30% from baseline, as nuclear hypoxia inducible factor (HIF)-1α increased by ∼53% and ∼37%. When ARSB was silenced, nuclear HIF-1α increased by ∼81% and ∼61% from baseline, and mRNA expression increased to 3.73 (±0.34) times baseline. Inversely, ARSB overexpression reduced nuclear HIF-1α by ∼37% and ∼54% from baseline in the epithelial cells. Hypoxia, like ARSB silencing, significantly increased the total cellular sulfated glycosaminoglycans and chondroitin-4-sulfate (C4S) content. Both hypoxia and ARSB silencing had similar effects on the cellular redox status and on mRNA expression of hypoxia-associated genes. Transcriptional effects of both ARSB silencing and hypoxia may be mediated by reduction in galectin-3 binding to more highly sulfated C4S, since the galectin-3 that co-immunoprecipitated with C4S declined and the nuclear galectin-3 increased following ARSB knockdown and hypoxia.
doi:10.1371/journal.pone.0033250
PMCID: PMC3302843  PMID: 22428001
11.  Lipopolysaccharide-induced Activation of NF-κB Non-Canonical Pathway Requires BCL10 Serine 138 and NIK Phosphorylations 
Experimental cell research  2010;316(19):3317-3327.
Background and Aims
B-cell lymphoma / leukemia (BCL)-10 and reactive oxygen species mediate two pathways of NF-κB (RelA) activation by lipopolysaccharide (LPS) in human colonic epithelial cells. The pathway for LPS activation of RelB by the non-canonical pathway (RelB) in non-myeloid cells was not yet reported, but important for understanding the range of potential microbial LPS-induced effects in inflammatory bowel disease.
Methods
Experiments were performed in human colonic epithelial cells and in mouse embryonic fibroblasts deficient in components of the IkappaB kinase (IKK) signalosome, in order to detect mediators of the non-canonical pathway of NF-κB activation, including nuclear RelB and p52 and phospho- and total NF-κB inducing kinase (NIK). BCL10 was silenced by siRNA and effects of mutations of specific phosphorylation sites of BCL10 (Ser138Gly and Ser218Gly) were determined.
Results
By the non-canonical pathway, LPS exposure increased nuclear RelB and p52, and phospho-NIK, with no change in total NIK. Phosphorylation of BCL10 Serine 138 was required for NIK phosphorylation, since mutation of this residue eliminated the increases in phospho-NIK and nuclear RelB and p52. Mutations of either Serine 138 or Serine 218 reduced RelA, p50, and phospho-IκBα of the canonical pathway. Effects of LPS stimulation and BCL10 silencing on NIK phosphorylation were demonstrated in confocal images.
Conclusions
LPS-induces activation of both canonical and non-canonical pathways of NF-κB in human colonic epithelial cells, and the non-canonical pathway requires phosphorylations of BCL10 (Serine 138) and NIK. These findings demonstrate the important role of BCL10 in mediating LPS-induced inflammation in human colonic epithelial cells and may open new avenues for therapeutic interventions.
doi:10.1016/j.yexcr.2010.05.004
PMCID: PMC2963716  PMID: 20466000
Lipopolysaccharide; BCL10; IKK signalosome; NF-κB
12.  Carrageenan-Induced Innate Immune Response is Modified by Enzymes that Hydrolyze Distinct Galactosidic Bonds 
The common food additive carrageenan predictably induces intestinal inflammation in animal models. Mechanisms of carrageenan-induced NFκB and IL-8 stimulation include an immune-mediated pathway involving toll-like receptor 4 (TLR4) and B-cell lymphoma/leukemia 10 (BCL10) and a reactive-oxygen species (ROS)-mediated pathway. To determine how the structure of CGN contributes to its initiation of inflammation by these two distinct mechanisms, we treated carrageenans with galactosidases and carrageenases, and determined the impact on IL-8 secretion and BCL10 production. Hydrolysis of carrageenan by the enzyme α-1→(3,6)-galactosidase significantly reduced the increases in IL-8 and BCL10, but other galactosidases tested, including α-1→6-, β-1→4-, and β-1→3,6-galactosidases had no effect. In contrast, specific κ- or ι-carrageenases, which hydrolyze the β-1,4-galactosidic bonds, produced increases in IL-8 and BCL10, attributable to increased exposure of the immunogenic α-1→3-galactosidic epitope of carrageenan to TLR4. These results were consistent with induction of the innate immune response by an interaction of TLR4 with the unusual α-D-Gal-(1→3)-D-Gal epitope that is present in carrageenan. Activation of the ROS-mediated pathway was unaffected by treatment of κ-CGN with either κ-CGNase (3 mg/L), α-1→(3,6)-galactosidase (20 mU/ml), or these enzymes in combination, indicating that the changes in IL-8 production were attributable to effects on the TLR4-BCL10-mediated innate immune pathway of induction of inflammation. These findings provide new information about the specificity of the carbohydrate-protein interaction between carrageenan and TLR4 and may help to devise treatments that modify the immune reactivity induced by carbohydrate antigens.
doi:10.1016/j.jnutbio.2009.07.002
PMCID: PMC2888704  PMID: 19864123
carrageenan; inflammation; food additive; galactosidase; carrageenase
13.  Chloroquine reduces arylsulphatase B activity and increases chondroitin-4-sulphate: implications for mechanisms of action and resistance 
Malaria Journal  2009;8:303.
Background
The receptors for adhesion of Plasmodium falciparum-infected red blood cells (RBC) in the placenta have been identified as chondroitin-4-sulphate (C4S) proteoglycans, and the more sulphate-rich chondroitin oligosaccharides have been reported to inhibit adhesion. Since the anti-malarial drug chloroquine accumulates in lysosomes and alters normal lysosomal processes, the effects of chloroquine on the lysosomal enzyme arylsulphatase B (ASB, N-acetylgalactosamine-4-sulphatase), which removes 4-sulphate groups from chondroitin-4-sulphate, were addressed. The underlying hypothesis derived from the recognized impairment of attachment of parasite-infected erythrocytes in the placenta, when chondroitin-4-sulphation was increased. If chloroquine reduced ASB activity, leading to increased chondroitin-4-sulphation, it was hypothesized that the anti-malarial mechanism of chloroquine might derive, at least in part, from suppression of ASB.
Methods
Experimental methods involved cell culture of human placental, bronchial epithelial, and cerebrovascular cells, and the in vitro exposure of the cells to chloroquine at increasing concentrations and durations. Measurements of arylsulphatase B enzymatic activity, total sulphated glycosaminoglycans (sGAG), and chondroitin-4-sulphate (C4S) were performed using in vitro assays, following exposure to chloroquine and in untreated cell preparations. Fluorescent immunostaining of ASB was performed to determine the effect of chloroquine on cellular ASB content and localization. Mass spectrometry and high performance liquid chromatography were performed to document and to quantify the changes in chondroitin disaccharides following chloroquine exposure.
Results
In the human placental, bronchial epithelial, and cerebrovascular cells, exposure to increasing concentrations of chloroquine was associated with reduced ASB activity and with increased concentrations of sGAG, largely attributable to increased C4S. The study data demonstrated: 1) decline in ASB activity following chloroquine exposure; 2) inverse correlation between ASB activity and C4S content; 3) increased content of chondroitin-4-sulphate disaccharides following chloroquine exposure; and 4) decline in extent of chloroquine-induced ASB reduction with lower baseline ASB activity. Confocal microscopy demonstrated the presence of ASB along the cell periphery, indicating extra-lysosomal localization.
Conclusions
The study data indicate that the therapeutic mechanism of chloroquine action may be attributable, at least in part, to reduction of ASB activity, leading to increased chondroitin-4-sulphation in human placental, bronchial epithelial, and cerebrovascular cells. In vivo, increased chondroitin-4-sulphation may reduce the attachment of P. falciparum-infected erythrocytes to human cells. Extra-lysosomal localization of ASB and reduced impact of chloroquine when baseline ASB activity is less suggest possible mechanisms of resistance to the effects of chloroquine.
doi:10.1186/1475-2875-8-303
PMCID: PMC2805689  PMID: 20017940
14.  ROS, Hsp27, and IKKβ Mediate Dextran Sodium Sulfate (DSS) Activation of IκBa, NFκB, and IL-8 
Inflammatory bowel diseases  2009;15(5):673-683.
Background
Dextran sodium sulfate (DSS) is a sulfated polysaccharide that has been very widely used to induce inflammation in experimental models of inflammatory bowel disease in which the effects of pharmacologic and biologic therapies are tested. However, the precise mechanisms by which DSS induces inflammation have not been elucidated.
Methods
DSS-induced increases in phospho-IκBα, nuclear NFκB (p65), and IL-8 secretion in human colonic epithelial cells in tissue culture are attributable to a reactive oxygen species (ROS)-induced pathway of inflammation, and do not require TLR4, MyD88, or Bcl10, which are associated with the innate immune pathway of NFκB-IL-8 activation.
Results
DSS-induced increases were inhibited by the ROS scavengers Tempol and Tiron, were associated with decreased phosphorylation of MAPK12 (p38γ), MAPK 13 (p38δ), and Hsp27, and required the IκB kinase (IKK) signalosome component IKKβ. In ex vivo colonic tissue from TLR4-deficient mice, or following knockdown of MyD88 or Bcl10 or exposure to an IRAK 1/4 inhibitor, DSS effects were not suppressed. Data demonstrated that DSS activates IκBα, NFκB, and IL-8 through an ROS-Hsp27-IKKβ-mediated pathway, and not through an innate immune cascade.
Conclusions
These results suggest that DSS models of inflammation may not be optimal for evaluation of interventions that involve mechanisms of innate immunity.
doi:10.1002/ibd.20821
PMCID: PMC2688460  PMID: 19085995
inflammation; reactive oxygen species (ROS); sulfated polysaccharide; IKK signalosome; Bcl10; innate immunity; Hsp27
15.  Priorities for nucleotide trace, sequence and annotation data capture at the Ensembl Trace Archive and the EMBL Nucleotide Sequence Database 
Nucleic Acids Research  2007;36(Database issue):D5-D12.
The Ensembl Trace Archive (http://trace.ensembl.org/) and the EMBL Nucleotide Sequence Database (http://www.ebi.ac.uk/embl/), known together as the European Nucleotide Archive, continue to see growth in data volume and diversity. Selected major developments of 2007 are presented briefly, along with data submission and retrieval information. In the face of increasing requirements for nucleotide trace, sequence and annotation data archiving, data capture priority decisions have been taken at the European Nucleotide Archive. Priorities are discussed in terms of how reliably information can be captured, the long-term benefits of its capture and the ease with which it can be captured.
doi:10.1093/nar/gkm1018
PMCID: PMC2238915  PMID: 18039715
16.  EMBL Nucleotide Sequence Database in 2006 
Nucleic Acids Research  2006;35(Database issue):D16-D20.
The EMBL Nucleotide Sequence Database () at the EMBL European Bioinformatics Institute, UK, offers a large and freely accessible collection of nucleotide sequences and accompanying annotation. The database is maintained in collaboration with DDBJ and GenBank. Data are exchanged between the collaborating databases on a daily basis to achieve optimal synchrony. Webin is the preferred tool for individual submissions of nucleotide sequences, including Third Party Annotation, alignments and bulk data. Automated procedures are provided for submissions from large-scale sequencing projects and data from the European Patent Office. In 2006, the volume of data has continued to grow exponentially. Access to the data is provided via SRS, ftp and variety of other methods. Extensive external and internal cross-references enable users to search for related information across other databases and within the database. All available resources can be accessed via the EBI home page at . Changes over the past year include changes to the file format, further development of the EMBLCDS dataset and developments to the XML format.
doi:10.1093/nar/gkl913
PMCID: PMC1897316  PMID: 17148479
17.  EMBL Nucleotide Sequence Database: developments in 2005 
Nucleic Acids Research  2005;34(Database issue):D10-D15.
The EMBL Nucleotide Sequence Database () at the EMBL European Bioinformatics Institute, UK, offers a comprehensive set of publicly available nucleotide sequence and annotation, freely accessible to all. Maintained in collaboration with partners DDBJ and GenBank, coverage includes whole genome sequencing project data, directly submitted sequence, sequence recorded in support of patent applications and much more. The database continues to offer submission tools, data retrieval facilities and user support. In 2005, the volume of data offered has continued to grow exponentially. In addition to the newly presented data, the database encompasses a range of new data types generated by novel technologies, offers enhanced presentation and searchability of the data and has greater integration with other data resources offered at the EBI and elsewhere. In stride with these developing data types, the database has continued to develop submission and retrieval tools to maximise the information content of submitted data and to offer the simplest possible submission routes for data producers. New developments, the submission process, data retrieval and access to support are presented in this paper, along with links to sources of further information.
doi:10.1093/nar/gkj130
PMCID: PMC1347492  PMID: 16381823
18.  Relationship between the tissue-specificity of mouse gene expression and the evolutionary origin and function of the proteins 
Genome Biology  2005;6(7):R56.
A microaaray analysis of mouse gene expression combined with the proteins functional and phyletic classification suggests that phyletic age (and not function) is the dominant factor shaping the expression profle of a protein.
Background
The combination of complete genome sequence information with expression data enables us to characterize the relationship between a protein's evolutionary origin or functional category and its expression pattern. In this study, mouse proteins were assigned into functional and phyletic groups and the gene expression patterns of the different protein groupings were examined by microarray analysis in various mouse tissues.
Results
Our results suggest that the proteins that are universally distributed in all tissues are predominantly enzymes and transporters. In contrast, the tissue-specific set is dominated by regulatory proteins (signal transduction and transcription factors). An increased tendency to tissue-specificity is observed for metazoan-specific proteins. As the composition of the phyletic groups highly correlates with that of the functional groups, the data were tested in order to determine which of the two factors - function or phyletic age - is dominant in shaping the expression profile of a protein. The observed differences in expression patterns of genes between functional groups were found mainly to reflect their different phyletic origin. The connection between tissue specificity and phyletic age cannot be explained by the recent rate of evolution. Finally, although metazoan-specific proteins tend to be tissue-specific compared with phyletically conserved proteins present in all domains of life, many such 'universal' proteins are also tissue-specific.
Conclusion
The minimal cellular transcriptome of the metazoan cell differs from that of the ancestral unicellular eukaryote: new functions were added (metazoan-specific proteins), whilst other functions became specialized and no longer took place in all cells (tissue-specific pre-metazoan proteins).
doi:10.1186/gb-2005-6-7-r56
PMCID: PMC1175987  PMID: 15998445

Results 1-18 (18)