Synthesis and Structure-Activity Relationships of Arylsulfonamides as AIMP2-DX2 Inhibitors for the Development of a Novel Anticancer Therapy.

AIMP2-DX2, a splicing variant of AIMP2, is up-regulated in lung cancer, possesses oncogenic activity, and results in tumorigenesis. Specifically inhibiting the interaction between AIMP2-DX2 and HSP70 to suppress AIMP2-DX2-dependent cancers with small molecules is considered a promising avenue for cancer therapeutics. Optimization of hit BC-DXI-04 (IC50 = 40.1 µM) provided new potent sulfonamide based AIMP2-DX2 inhibitors. Among these, BC-DXI-843 showed improved inhibition against AIMP2-DX2 (IC50 = 0.92 µM) with more than 100-fold selectivity over AIMP2 in a luciferase assay. Several binding assays indicated that this compound effectively induces cancer cell apoptosis by specifically interrupting the interaction between DX2 and HSP70, which leads to the degradation of DX2 via Siah1-mediated ubiquitination. More importantly, BC-DXI-843 demonstrated in vivo efficacy in a tumor xenograft mouse model (H460 cells) at a dosage of 50 mg/kg, suggesting it as a promising lead for development of novel therapeutics targeting AIMP2-DX2 in lung cancer.

Targeting cancer's Achilles' heel: role of BCL-2 inhibitors in cellular senescence and apoptosis.

Members of the antiapoptotic BCL-2 proteins are involved in tumor growth, progression and survival, and are also responsible for chemoresistance to conventional anticancer agents. Early efforts to target these proteins yielded some active compounds; however, newer methodologies involving structure-based drug design, Nuclear Magnetic Resonance (NMR)-based screening and fragment-based screening yielded more potent compounds. Discovery of specific as well as nonspecific inhibitors of this class of proteins has resulted in great advances in targeted chemotherapy and decrease in chemoresistance. Here, we review the history and current progress in direct as well as selective targeting of the BCL-2 proteins for anticancer therapy.

TIMP3 expression associates with prognosis in colorectal cancer and its novel arylsulfonamide inducer, MPT0B390, inhibits tumor growth, metastasis and angiogenesis.

Tissue inhibitors of metalloproteinase 3 (TIMP3) are a major endogenous inhibitor of matrix metalloproteinase (MMPs) that inhibit tumor growth, invasion, metastasis and angiogenesis. In this study, we found that TIMP3 expression is associated with positive prognosis of colorectal cancer (CRC) clinicopathologically. Therefore, we developed a series of arylsulfonamide derivatives as TIMP3 inducers in order to define potential colorectal cancer therapeutic agent. Among these, MPT0B390 was selected for anti-tumor, anti-metastasis, and anti-angiogenesis property determination. Methods: The relationship between TIMP3 expression and clinical pathological features in colorectal patients and cell lines were determined by immunohistochemistry, bioinformatics analysis and western blotting. The anti-tumor function was validated by using MTT, apoptosis pathway detection and in vivo xenograft model for tumor growth inhibition determination. The anti-metastatic function was validated using a transwell migration assay, and using in vivo lung metastasis and liver metastasis models. The mechanism of MPT0B390-induced TIMP3 expression was further tested using qPCR and Chromatin IP assay. The anti-angiogenesis function was examined by using transwell migration assay, and in vivo Matrigel plug assay. Results: After screening candidate compounds, we identified MPT0B390 as an effective inducer of TIMP3. We showed that MPT0B390 induces TIMP3 expression significantly and inhibits CRC cell growth in vitro and in vivo. By inducing TIMP3 expression, MPT0B390 can also exert its anti-metastasis effect to inhibit CRC cell migration and invasion and downregulates migration markers such as uPA, uPAR, and c-Met. Subsequent Chromatin immunoprecipitation assay revealed that MPT0B390 can significantly inhibit EZH2 expression as well as its binding to TIMP3 promoter region to regulate TIMP3 induction. In addition to the anti-tumor and anti-metastasis capability, MPT0B390 can also induce TIMP3 expression in endothelial cells to inhibit tumor angiogenesis. Conclusion: These data suggest the potential therapeutic applications of the TIMP3 inducer, MPT0B390, for colorectal cancer treatment.

Suplatast tosilate reduces radiation-induced lung injury in mice through suppression of oxidative stress.

PURPOSE: Although radiotherapy is important in the treatment of malignant thoracic tumors, it has harmful effects on healthy tissues. We previously showed that suplatast tosilate, an anti-allergic agent, scavenged reactive oxygen species (ROS), including hydroxyl radicals. Because ROS-mediated oxidative stress is involved in radiation-induced lung injury, we hypothesized that suplatast tosilate could reduce radiation-induced lung injury via suppression of oxidative stress. METHODS AND MATERIALS: Murine alveolar epithelial cells were irradiated with or without a medium containing suplatast tosilate in vitro to determine whether the agent had cytoprotective effects against radiation-induced injury. On the other hand, the thoracic region of C57BL/6 mice was exposed to a single irradiation dose of 15 Gy and the effects of suplatast tosilate were determined by a histological evaluation and assessment of the following parameters: cell number and inflammatory cytokine levels in bronchoalveolar lavage fluid, and oxidative stress markers and hydroxyproline content in pulmonary tissues. RESULTS: Suplatast tosilate protected murine alveolar epithelial cells in vitro from irradiation-induced inhibition of cell proliferation, which was accompanied by the suppression of intracellular ROS and DNA double-strand breaks induced by irradiation. Oxidative stress markers and the levels of inflammatory and fibrogenic cytokines were upregulated in irradiated murine lungs in vivo. Suplatast tosilate suppressed both oxidative stress markers and the levels of cytokines, which resulted in reduced pulmonary fibrosis and clearly improved the survival rate after irradiation. CONCLUSIONS: These findings demonstrate that suplatast tosilate could be a useful lung-protective agent that acts via suppression of oxidative stress associated with thoracic radiotherapy.

Th2 and Th17 Induce Dry Skin in a Mouse Model of Arthritis.

Skin dryness is a characteristic of rheumatoid arthritis (RA) model mice. However, the mechanism underlying the induction of dry skin by RA is unclear. We hypothesized that T helper (Th)2 and Th17 cells mediate this process. A mouse model of DBA/1JJmsSlc collagen-induced arthritis was treated with Th2 or Th17 cell inhibitor, and transepidermal water loss (TEWL) and the expression of markers associated with allergic reaction and inflammation were evaluated. TEWL and plasma levels of thymic stromal lymphopoietin, interleukin (IL)-6 and -17, and tumor necrosis factor (TNF)-α were increased in the arthritis mouse model compared to that in control mice. Administration of Th2 cell inhibitor abolished the increase in TEWL, IL-6, and TNF-α levels, whereas Th17 cell inhibitor reversed TEWL and decreased IL-17 level. Th2 and Th17 cells contribute to the induction of dry skin, but via distinct mechanisms.

Effect of sulfonylurea tribenuron methyl herbicide on soil Actinobacteria growth and characterization of resistant strains

ABSTRACT Repeated application of pesticides disturbs microbial communities and cause dysfunctions on soil biological processes. Granstar® 75 DF is one of the most used sulfonylurea herbicides on cereal crops; it contains 75% of tribenuron-methyl. Assessing the changes on soil microbiota, particularly on the most abundant bacterial groups, will be a useful approach to determine the impact of Granstar® herbicide. For this purpose, we analyzed Actinobacteria, which are known for their diversity, abundance, and aptitude to resist to xenobiotic substances. Using a selective medium for Actinobacteria, 42 strains were isolated from both untreated and Granstar® treated soils. The number of isolates recovered from the treated agricultural soil was fewer than that isolated from the corresponding untreated soil, suggesting a negative effect of Granstar® herbicide on Actinobacteria community. Even so, the number of strains isolated from untreated and treated forest soil was quite similar. Among the isolates, resistant strains, tolerating high doses of Granstar® ranging from 0.3 to 0.6% (v/v), were obtained. The two most resistant strains (SRK12 and SRK17) were isolated from treated soils showing the importance of prior exposure to herbicides for bacterial adaptation. SRK12 and SRK17 strains showed different morphological features. The phylogenetic analysis, based on 16S rRNA gene sequencing, clustered the SRK12 strain with four Streptomyces type strains (S. vinaceusdrappus, S. mutabilis, S. ghanaensis and S. enissocaesilis), while SRK17 strain was closely related to Streptomyces africanus. Both strains were unable to grow on tribenuron methyl as unique source of carbon, despite its advanced dissipation. On the other hand, when glucose was added to tribenuron methyl, the bacterial development was evident with even an improvement of the tribenuron methyl degradation. In all cases, as tribenuron methyl disappeared, two compounds were detected with increased concentrations. These by-products appeared to be persistent and were not degraded either chemically or by the studied strains. Based on these observations, we suggested that bacterial activity on carbon substrates could be directly involved in the partial breakdown of tribenuron methyl, by generating the required acidity for the first step of the hydrolysis. Such a process would be interesting to consider in bioremediation of neutral and alkaline tribenuron methyl-polluted soils.

Mitochondria and DNA Targeting of 5,10,15,20-Tetrakis(7-sulfonatobenzo[b]thiophene) Porphyrin-Induced Photodynamic Therapy via Intrinsic and Extrinsic Apoptotic Cell Death.

Photodynamic therapy (PDT) selectively targets subcellular organelles and promises an excellent therapeutic strategy for cancer treatment. Here, we report the synthesis of a new water-soluble photosensitizer, 5,10,15,20-tetrakis (7-sulfonatobenzo[b]thiophene) porphyrin (SBTP). Rational design of the porphyrinic molecule containing benzo[b]thiophene moiety at the meso-position led to selective accumulation in both mitochondria and nucleus of MCF-7 cells. This multitarget ability of SBTP can cause damage to mitochondria as well as DNA simultaneously. FACS analysis showed rapid cellular uptake of SBTP. High-content cell-based assay was executed to concurrently monitor increase of cytosolic Ca(2+) levels, mitochondrial permeability transition (MPT), and caspase-3/7/8 activation in MCF-7 cells under the pathological condition caused by PDT action of SBTP. The study of cell death dynamics showed that PDT action of SBTP caused an increase in the MPT followed by an increase in cytosolic Ca(2+) level. The localization of SBTP in the mitochondria activated the intrinsic apoptotic pathway. Additionally, localization of SBTP in the nucleus led to DNA damage in MCF-7 cells. The DNA fragmentation that occurred by PDT action of SBTP was thought to be responsible for extrinsic apoptosis of MCF-7 cells. SBTP demonstrated effective PDT activity of 5 µM IC50 value to MCF-7 cells by bitargeting mitochondria and DNA.

Novel Bioactive Hybrid Compound Dual Targeting Estrogen Receptor and Histone Deacetylase for the Treatment of Breast Cancer.

A strategy to develop chemotherapeutic agents by combining several active groups into a single molecule as a conjugate that can modulate multiple cellular pathways may produce compounds having higher efficacy compared to that of single-target drugs. In this article, we describe the synthesis and evaluation of an array of dual-acting ER and histone deacetylase inhibitors. These novel hybrid compounds combine an indirect antagonism structure motif of ER (OBHS, oxabicycloheptene sulfonate) with the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). These OBHS-HDACi conjugates exhibited good ER binding affinity and excellent ERα antagonistic activity, and they also exhibited potent inhibitory activities against HDACs. Compared with the approved drug tamoxifen, these conjugates exhibited higher antitumor potency in ERα-positive breast cancer cells (MCF-7). Moreover, these conjugates not only showed selective anticancer activity that was more potent against MCF-7 cells than DU 145 (prostate cancer), but they had no toxicity toward normal cells.

Structure-activity relationship of nonsecosteroidal vitamin D receptor modulators.

The vitamin D receptor (VDR), a receptor for the secosteroid 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], is a promising drug target in the treatment of bone and mineral disorders, cancer, autoimmune disease, infection, and cardiovascular disease. Indeed, approximately 100 nonsecosteroidal VDR modulators (VDRMs) have been developed. Analysis of X-ray crystal structures reveals: (i) nonsecosteroidal VDRMs bind to VDR in a position similar to 1,25(OH)2D3; (ii) hydrogen bond interactions between ligands and VDR are the most important for VDR binding; (iii) hydrophobic interactions and CH-π interactions in aromatic ligands are also important for VDR binding; and (iv) exchange of C-O-C linkage to C-CH2-C linkage in VDRMs increases transactivation activity, probably as a result of an entropic effect of solvation/desolvation of molecules. Several VDRMs have better therapeutic efficacy when compared to 1,25(OH)2D3 in experimental models of cancer and osteoporosis with less induction of hypercalcemia, a major potential adverse effect in the clinical application of VDR ligands.

Synthesis and structure-activity relationship of mono-indole-, bis-indole-, and tris-indole-based sulfonamides as potential anticancer agents.

A series of arylsulfonyl mono-indoles (10-15), bis-indoles (16-27), and tris-indoles (28-32) have been synthesized and evaluated for their cytotoxicity toward four human cancer cell lines including HuCCA-1 (cholangiocarcinoma), HepG2 (hepatocellular carcinoma), A-549 (lung carcinoma), and MOLT-3 (lymphoblastic leukemia). Most of the synthesized indoles displayed cytotoxicity against the MOLT-3 cell line except for analogs 16, 17, and 32. Significantly, the [Formula: see text]-sulfonylphenolic bis-indole series (18-27) and the [Formula: see text]-chlorobenzenesulfonyl tris-indole (30) showed higher antiproliferative activity against HepG2 cell than the reference drug, etoposide. Promisingly, the [Formula: see text]-chlorobenzenesulfonyl bis-indole (20) and tris-indole (30) provided 3-fold and 2-fold stronger activity, respectively, against HepG2 cell than etoposide. Moreover, the phenolic bis-indole (20) was also shown to be the most potent cytotoxic agent against HuCCA-1 and A-549 cell lines with [Formula: see text] values of 7.75 and [Formula: see text], respectively. The tris-indole analogs 28, 29, and 31 also exhibited selectivity against MOLT-3 cell. The findings disclosed that [Formula: see text]-arylsulfonyl bis-indoles-bearing phenolic groups are potentially interesting lead pharmacophores of anticancer agents that should be further investigated in more detail.

Design, synthesis, biological evaluation, and structure-activity relationships of substituted phenyl 4-(2-oxoimidazolidin-1-yl)benzenesulfonates as new tubulin inhibitors mimicking combretastatin A-4.

Sixty-one phenyl 4-(2-oxoimidazolidin-1-yl)benzenesulfonates (PIB-SOs) and 13 of their tetrahydro-2-oxopyrimidin-1(2H)-yl analogues (PPB-SOs) were prepared and biologically evaluated. The antiproliferative activities of PIB-SOs on 16 cancer cell lines are in the nanomolar range and unaffected in cancer cells resistant to colchicine, paclitaxel, and vinblastine or overexpressing the P-glycoprotein. None of the PPB-SOs exhibit significant antiproliferative activity. PIB-SOs block the cell cycle progression in the G(2)/M phase and bind to the colchicine-binding site on ß-tubulin leading to cytoskeleton disruption and cell death. Chick chorioallantoic membrane tumor assays show that compounds 36, 44, and 45 efficiently block angiogenesis and tumor growth at least at similar levels as combretastatin A-4 (CA-4) and exhibit low to very low toxicity on the chick embryos. PIB-SOs were subjected to CoMFA and CoMSIA analyses to establish quantitative structure-activity relationships.

Structure--activity relationship studies of novel arylsulfonylimidazolidinones for their anticancer activity.

To define the SAR, a series of novel N-arylsulfonylimidazolidinone derivatives were evaluated for their in vitro anticancer activity against five human tumor cell lines, including A549, COLO205, KATO III, K562, SK-OV-3 and murine leukemia (P288D1) cell line. Among them, N-(2-chloroacetyl)-6-(2-oxo-4-phenylimidazolidin-1-ylsulfonyl)-3,4-dihydroquinoline-1(2H)-carboxamide (4m) and N-cyclohexyl-6-(2-oxo-4-phenylimidazolidin-1-ylsulfonyl)-3,4-dihydroquinoline-1(2H)-carboxamide (4n) exhibited comparable in vitro anticancer activity to doxorubicin against A549, KATO III and K562 cell lines and gave superior xenographic results against NCI-H23 and SW620 cancer cell lines. Regarding the structure-activity relationship, two critical points were discovered; the steric congestion at 4-position of N-arylsulfonylimidazolidinone scaffold abolishes the activity and the bulkiness or hydrophobicity of acyl groups at 3,4-dihydroquinoline of 4, especially with carbamoyl moiety, enormously enhances the activity.

Inhibitory effects of suplatast tosilate on the differentiation and function of monocyte-derived dendritic cells from patients with asthma.

BACKGROUND: Dendritic cells (DCs) are antigen-presenting cells that efficiently activate T cells. OBJECTIVE: We examined the effects of suplatast tosilate, which prevents T-helper type 2 responses, on the differentiation and function of monocyte-derived DCs (moDCs). METHODS: DCs were differentiated in vitro from peripheral monocytes from patients with asthma by the addition of granulocyte macrophage colony-stimulating factor and IL-4 in the presence or absence of suplatast tosilate. Cell surface molecules (CD1a, CD14, CD80, CD83, CD86, HLA-DR) on immature and mature DCs were analysed with flow cytometry, and the secretion of CC chemokine ligand (CCL)17 (thymus and activation-regulated chemokine), IL-12p70, IL-12p40, and IL-10 was measured with an ELISA. We also studied the proliferative responses of allogeneic CD4(+) T cells from healthy subjects to DCs differentiated in the presence of suplatast tosilate. In addition, the production of IFN-gamma and IL-5 by CD4(+) T cells after coculture with untreated DCs or suplatast tosilate-treated DCs was measured with ELISA. RESULTS: Suplatast tosilate significantly inhibited the expression of CD1a, CD80, and CD86 on immature DCs and of CD1a, CD80, CD83, and CD86 on mature DCs. Suplatast tosilate also significantly inhibited the secretion of CCL17, IL-12p70, and IL-12p40; however, the secretion of IL-10 was not affected. The proliferative responses of allogeneic CD4(+) T cells to suplatast tosilate-treated DCs were suppressed. Moreover, suplatast tosilate-treated DCs had an impaired capacity to stimulate CD4(+) T cells to produce IFN-gamma and IL-5. CONCLUSION: Suplatast tosilate inhibits the differentiation, maturation, and function of moDCs.

Intravesical suplatast tosilate (IPD-1151T) inhibits experimental bladder inflammation.

PURPOSE: Interstitial cystitis is a painful bladder disease characterized by urgency, frequency and variable inflammation but there is no curative therapy. Suplatast tosilate (IPD-1151T) is an immunoregulatory compound that decreases interstitial cystitis symptoms but to our knowledge its mechanism of action is unknown. We investigated the effect of intravesical IPD-1151T on mediator release from bladder explants in experimental cystitis. MATERIALS AND METHODS: A catheter was inserted into the bladder of female mice. After urine was emptied normal saline, carbachol (100 nM) or lipopolysaccharide (10 mg/ml) was introduced with or without 10-minute pretreatment with IPD-1151T. Urine was removed after 45 minutes for histamine and tumor necrosis factor-alpha assays. The bladder was removed after 4 hours, minced into 1 mm2 pieces and cultured with or without triggers overnight for mediator release. The effect of IPD-1151T was also tested on rat skin vascular permeability as well as on purified rat peritoneal mast cells and human cord blood derived mast cells. RESULTS: Carbachol significantly increased histamine release in urine (61.3% in 8 preparations, p<0.05) but not in explant medium. IPD-1151T inhibited this effect by 77%. Lipopolysaccharide induced a 350% urine histamine increase in 9 preparations (p<0.05) and a 300% tumor necrosis factor-alpha increase in explant medium. IPD-1151T inhibited the lipopolysaccharide induced medium tumor necrosis factor-alpha increase by 95% in 5 preparations (p<0.05). IPD-1151T did not inhibit rat skin vascular permeability or purified rat peritoneal mast cell activation by compound 48/80 or human cord blood derived mast cells by anti-IgE. CONCLUSIONS: IPD-1151T inhibits bladder release of histamine and tumor necrosis factor-alpha through a mechanism that does not appear to involve direct mast cell inhibition. These findings may justify a beneficial effect of IPD-1151T in interstitial cystitis.

Synthesis and anti-diabetic activity of (RS)-2-ethoxy-3-{4-[2-(4-trifluoro-methanesulfonyloxy-phenyl)-ethoxy]-phenyl}-propionic acid.

AIM: To synthesize and study the anti-diabetic activity of (RS)-2-ethoxy-3-{4-[2-(4-trifluoromethanesulfonyloxy-phenyl)-ethoxy]-phenyl}-propionic acid (compound I). METHODS: Compound I was prepared in 6 steps, using 4-(2-hydroxy-ethyl)-phenol as the starting material. The in vitro selectivity and potency of target compound I, rosiglitazone and WY-14643 on human PPARalpha and PPARgamma were determined in reporter gene assays. In vivo, rosiglitazone and compound I were administered orally to KK(Ay) mice for 14 d. Insulin tolerance tests and oral glucose tolerance tests were performed on the 10th and 14th day of treatment, respectively. At the end of the treatment, sera were collected for biochemical analysis. RESULTS: In vitro, compound I significantly activated both PPARalpha and PPARgamma. In vivo, compound I corrected the impaired insulin and glucose tolerance of KK(Ay) mice, and produced a significant reduction in plasma triglyceride levels after 14 d of treatment. The effect produced was significant compared with the control group. CONCLUSION: Both in vitro and in vivo anti-diabetic activity studies for compound I were conducted and the data suggest that this compound is a potentially effective anti-diabetic agent.

Identification and characterization of noncalcemic, tissue-selective, nonsecosteroidal vitamin D receptor modulators.

Vitamin D receptor (VDR) ligands are therapeutic agents for the treatment of psoriasis, osteoporosis, and secondary hyperparathyroidism. VDR ligands also show immense potential as therapeutic agents for autoimmune diseases and cancers of skin, prostate, colon, and breast as well as leukemia. However, the major side effect of VDR ligands that limits their expanded use and clinical development is hypercalcemia that develops as a result of the action of these compounds mainly on intestine. In order to discover VDR ligands with less hypercalcemia liability, we sought to identify tissue-selective VDR modulators (VDRMs) that act as agonists in some cell types and lack activity in others. Here, we describe LY2108491 and LY2109866 as nonsecosteroidal VDRMs that function as potent agonists in keratinocytes, osteoblasts, and peripheral blood mononuclear cells but show poor activity in intestinal cells. Finally, these nonsecosteroidal VDRMs were less calcemic in vivo, and LY2108491 exhibited more than 270-fold improved therapeutic index over the naturally occurring VDR ligand 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] in an in vivo preclinical surrogate model of psoriasis.

Effects of metsulfuron-methyl on the microbial population and enzyme activities in wheat rhizosphere soil.

The effects of metsulfuron-methyl, a sulfonylurea herbicide, on the wheat soil microorganisms were evaluated by the methods of microbial inoculation culture, and the activities of three enzymes were measured using the colorimetric method. The tolerant microorganisms that can resist 500 microg x g(-1) metsulfuron-methyl in the counting culture medium were studied specially. Metsulfuron-methyl distinctly inhibited the common aerobic heterotriphic bacteria, but the effects on common fungi and common actinomycete were not evident. In the meantime, the number of tolerant fungi increased greatly in the rhizosphere after the application of metsulfuron-methyl in contrast to the significant decrease of the amount of tolerant actinomycete. It indicates that fungi might turn into the dominant microbial type and actinomycete is the sensitive factor in the soil polluted by sulfonylurea residues. The population of aromatic compounds-decomposing bacteria, aerobic azotobacter, and nitrite bacteria all increased in the earlier period, but the aerobic azotobacter decreased rapidly in number 30 days later, and the amount of nitrite bacteria also showed a temporary decrease with time 15 days later. However, the denitrifying bacteria just began to increase significantly after the crops had grown for 50 days. The amount of sulfur-oxidizing bacteria gradually decreased with the growth of crops, and so were the sulfate-reducing bacteria after metsulfuron-methyl application. To all types of microorganisms, there were more microbes in rhizosphere samples than those in nonrhizosphere except aerobic azotobacter. It means the growth of wheat root system can stimulate the growth of most microorganisms. The activities of hydrogen peroxidase and polyphenol oxidase in soil samples after metsulfuron-methyl application were notably lower than those in the control, and the difference of the activities between the samples of rhizosphere and nonrhizosphere was evident. On the contrary, the activity of dehydrogenase was not inhibited by the application of metsulfuron-methyl, and the rhizosphere effect was not obvious either.

Effect of suplatast tosilate on goblet cell metaplasia in patients with asthma.

BACKGROUND: Goblet cell metaplasia is a pathologic characteristic of asthma, associated with excess mucus secretion. Interleukin (IL)-4 and IL-13 plays an important role in mucus hypersecretion. Suplatast tosilate (suplatast), an antiallergic agent, is a Th2 cytokine inhibitor that suppresses the synthesis of IL-4, IL-5, IL-13, and eosinophilic airway inflammation. OBJECTIVE: We examined the effects of suplatast on mucus production in bronchial biopsy specimens taken from asthmatic subjects. METHODS: Oral suplatast 300 mg daily, or placebo was administered for 3 months in a double-blind, parallel-group study in 25 patients with asthma. Biopsy specimens were evaluated at before and after treatment for alcian blue/period acid-Schiff (AB/PAS), MUC5AC staining in bronchial epithelium and IL-4+, IL-13+ cells as well as inflammatory cells in lamina propria. RESULTS: There were significant decreases in the percentage of AB/PAS (P < 0.01) and MUC5AC (P < 0.01) stained area in the suplatast group. These changes were accompanied by significant decreases in IL-4+ and IL-13+ cells in suplatast-treated subjects. Additionally, we have observed that the number of infiltrating eosinophils and CD4+ T cells significantly decreased. CONCLUSIONS: These findings suggest that suplatast prevents goblet cell metaplasia through modulation of Th2 cytokine production and the recruitment of eosinophils and CD4+ T cells in the asthmatic airways.

Targeting of the virulence factor acetohydroxyacid synthase by sulfonylureas results in inhibition of intramacrophagic multiplication of Brucella suis.

The acetohydroxyacid synthase (AHAS) of Brucella suis can be effectively targeted by the sulfonylureas chlorimuron ethyl and metsulfuron methyl. Growth in minimal medium was inhibited, and multiplication in human macrophages was totally abolished with 100 microM of sulfonylureas. Metsulfuron methyl-resistant mutants showed reduced viability in macrophages and reduced AHAS activity.

In situ study of K+ transport into the vacuole of Saccharomyces cerevisiae.

Permeable spheroplasts were prepared from two strains of Saccharomyces cerevisiae by incubating with zymolyase without a permeabilizing agent. The loss of the plasma membrane barrier was confirmed by the nucleotide release, the activity of glucose 6-phosphate dehydrogenase with external substrates and by the effects on respiration of mitochondrial substrates and ADP. Mitochondrial integrity was maintained, as shown by respiration with lactate, pyruvate, glucose and ethanol, and its acceleration by ADP showed a coupled respiration. Potassium uptake into the vacuole was measured with a selective electrode and found to be taken up effectively by spheroplasts only in the presence of Mg-ATP; it was reverted by CCCP and PCP and inhibited by bafilomycin A1, but not by sodium vanadate or sodium azide. Potassium ions did not alter DeltaPsi of the vacuole, followed with oxonol V, but caused vacuolar alkalinization, as followed with pyranine. The increase of vacuolar pH was non-selective and observed at 50-200 mM of several monovalent cations. Isolated vacuoles with pyranine inside showed similar changes of the internal pH in the presence of KCl. Results indicate that some strains do not require a permeabilizing agent to directly access the vacuole in spheroplasts prepared with zymolyase. The hypothesis about the existence of a K+/H+ antiporter in the vacuolar membrane of S. cerevisiae is discussed.