PubMed Health⌕ Search

Biomedical subjects

M Kurowska

Publications and source records attributed to M Kurowska.

At least 19 recordsLinked to original sources
PubMed2006

Hepatocyte nuclear factor 4 alpha ligand binding and F domains mediate interaction and transcriptional synergy with the pancreatic islet LIM HD transcription factor Isl1.

The orphan nuclear receptor HNF4alpha and the LIM homeodomain factor Isl1 are co-expressed in pancreatic beta-cells and are required for the differentiation and function of these endocrine cells. HNF4alpha activates numerous genes and mutations in its gene are associated with maturity onset diabetes of the young. Cofactors and transcription factors that interact with HNF4alpha are crucial to modulate its transcriptional activity, since the latter is not regulated by conventional ligands. These transcriptional partners interact mainly through the HNF4alpha AF-1 module and the ligand binding domain, which contains the AF-2 module. Here, we showed that Isl1 could enhance the HNF4alpha-mediated activation of transcription of the HNF1alpha, PPARalpha and insulin I promoters. Isl1 interacted with the HNF4alpha AF-2 but also required the HNF4alpha carboxy-terminal F domain for optimal interaction and transcriptional synergy. More specifically, we found that naturally occurring HNF4alpha isoforms, differing only in their F domain, exhibited different abilities to interact and synergize with Isl1, extending the crucial transcriptional modulatory role of the HNF4alpha F domain. HNF4alpha interacted with both the homeodomain and the first LIM domain of Isl1. We found that the transcriptional synergy between HNF4alpha and Isl1 involved an increase in HNF4alpha loading on promoter. The effect was more pronounced on the rat insulin I promoter containing binding sites for both HNF4alpha and Isl1 than on the human HNF1alpha promoter lacking an Isl1 binding site. Moreover, Isl1 could mediate the recruitment of the cofactor CLIM2 resulting in a further transcriptional enhancement of the HNF1alpha promoter activity.

Animals↗
PubMed2002

Expression of IL-15 and IL-15 receptor isoforms in select structures of human fetal brain.

IL-15, a key cytokine linking innate and acquired immunity, is expressed in many cell types and tissues. Recent data indicate constitutive expression of IL-15 in human neural cell lines and tissues. The aim of the present study was to examine the expression patterns of mRNA encoding IL-15 and IL-15 receptor alpha (IL-15Ralpha) isoforms in select structures of human fetal brain. We report that mRNA for IL-15 and IL-15Ralpha isoforms were expressed in all tested brain structures: cerebral cortex, cerebellum, hippocampus, and thalamus. However, the levels of IL-15 and IL-15Ralpha mRNA were higher in the hippocampus and cerebellum in comparison with cortex and thalamus. Moreover, higher levels of cytosol in comparison with membrane-bound IL-15 isoform were present in all brain structures. The constitutive, but distinct, expression of IL-15 and its receptors in select human fetal brain structures suggests that IL-15 plays a role in their development and physiology.

Brain↗
PubMed2000

The mechanism of taurine chloramine inhibition of cytokine (interleukin-6, interleukin-8) production by rheumatoid arthritis fibroblast-like synoviocytes.

OBJECTIVE: Taurine chloramine (Tau-Cl) has been shown to inhibit the production of proinflammatory cytokines (interleukin-6 [IL-6] and IL-8) by fibroblast-like synoviocytes (FLS) isolated from rheumatoid arthritis (RA) patients. The present study was conducted to elucidate the mechanism of inhibitory action exerted by Tau-Cl. METHODS: The effects of Tau-Cl on 1) the transcription of genes coding for IL-6 and IL-8, and 2) the activity of nuclear factor kappaB (NF-kappaB) and activator protein 1 (AP-1) transcription factors, which are crucial for the transcription of these cytokine genes, were investigated in FLS isolated from the synovial tissue of RA patients. FLS were cultured in vitro for 3-6 passages and stimulated with recombinant human IL-1beta (1 ng/ml) in the presence of either Tau or Tau-Cl, which were added simultaneously with the stimulus at concentrations of 250 microM or 500 microM. The relative expression of IL-6 and IL-8 messenger RNA (mRNA) was evaluated after 4 hours of stimulation, using competitive reverse transcriptase-polymerase chain reaction. The DNA binding activity of NF-kappaB and AP-1 was examined 30 minutes and 2 hours after cell stimulation, respectively, using electromobility gel shift assay. RESULTS: IL-1beta triggered a significant rise in the activity of transcription factors NF-kappaB and AP-1, followed by an elevation of cytokine IL-6 and IL-8 mRNA expression. Tau-Cl, but not Tau, reduced IL-1beta-triggered cytokine mRNA expression, exerting stronger inhibitory activity on the levels of IL-6 than on those of IL-8. Importantly, Tau-Cl also diminished the activity of NF-kappaB and, to a lesser extent, that of AP-1 transcription factor. Neither IL-1beta nor Tau-Cl affected the activity of octamer transcription factor 1. CONCLUSION: Tau-Cl inhibition of IL-6 and IL-8 synthesis in FLS from RA patients results from the ability of this compound to diminish the activity of the major transcriptional regulators (NF-kappaB and AP-1), which subsequently reduces the transcription of these cytokine genes.

Aged↗
PubMed2000

Rottlerin, a PKC isozyme-selective inhibitor, affects signaling events and cytokine production in human monocytes.

The implication of select protein kinase C (PKC) isoenzymes in cytokine production by human monocytes was investigated using an isozyme-selective inhibitor of PKC, rottlerin. We found that lipopolysaccharide (LPS) triggers cytosol-to-membrane translocation of PKCalpha and delta isoenzymes, whereas phorbol ester (PMA) induces translocation of several PKC isoforms. Moreover, we show that in LPS- and PMA-stimulated monocytes rottlerin affects several cellular responses. (1) At low (15 microM) concentration it blocks translocation of PKCdelta, diminishes DNA binding activity of AP-1 transcription factor, and attenuates cytokine production [tumor necrosis factor alpha (TNF-alpha) > interleukin-1beta (IL-1beta)]. (2) At high (50 microM) concentration it prevents translocation of PKCalpha, and subsequently inhibits ERK1/ERK2 phosphorylation, DNA binding activities of AP-1 and nuclear factor-KB transcription factors, and the production of both tested cytokines. Thus, we propose that cytosol-to-membrane translocation of PKCalpha and PKdelta isoenzymes may represent early steps in the signaling cascades that lead to TNF-alpha and IL-1beta production in human monocytes.

Acetophenones↗
PubMed1999

Taurine chloramine inhibition of cell proliferation and cytokine production by rheumatoid arthritis fibroblast-like synoviocytes.

OBJECTIVE: To examine whether taurine (Tau) or its physiologic chlorinated derivative, taurine chloramine (Tau-CI), affects proliferation of, and proinflammatory cytokine (interleukin-6 [IL-6] and IL-8) production by, fibroblast-like synoviocytes (FLS) isolated from rheumatoid arthritis (RA) patients. METHODS: FLS, isolated from the synovial tissue of 19 RA patients and cultured in vitro for 3-6 passages, were stimulated with the recombinant human cytokines IL-1beta (1 ng/ml), tumor necrosis factor alpha (TNFalpha; 10 ng/ml), or IL-17 (10 ng/ml) in the presence of either Tau or Tau-Cl, which were added at concentrations of 50-500 microM. Tau and Tau-Cl were added simultaneously with, 2 hours before, or 24 hours after the stimuli. The concentrations of IL-6 and IL-8 were determined in culture supernatants using specific enzyme-linked immunosorbent assays. Proliferation of FLS was estimated on the basis of 3H-thymidine incorporation into the cells, which were cultured for 72 hours in the presence of recombinant human basic fibroblast growth factor (bFGF) (1 ng/ml) and Tau or Tau-Cl, which were added simultaneously at the beginning of the culture. RESULTS: Cultured in vitro, RA FLS spontaneously secreted low levels of IL-6 and IL-8, but when RA FLS were stimulated with IL-1beta, TNFalpha, or IL-17, significantly higher amounts of IL-6 and IL-8 were produced. Tau-Cl, but not Tau, inhibited cytokine-triggered synthesis of IL-6 (50% inhibitory concentration [IC50] approximately 225 microM) and IL-8 (IC50 approximately 450 microM) when added simultaneously with the stimuli. However, IL-17-induced production of IL-8 was not affected by Tau-Cl. In the cells prestimulated with IL-1beta for 24 hours, Tau-Cl still inhibited synthesis of IL-6, but did not affect IL-8 production. Moreover, Tau-Cl inhibited spontaneous and bFGF-triggered proliferation of FLS in a dose-dependent manner. Neither Tau nor Tau-Cl affected cell viability. CONCLUSION: The results of these studies demonstrate that Tau-Cl inhibits production of proinflammatory cytokines by RA FLS, as well as proliferation of these cells. Thus, Tau-Cl may act as a physiologic modulator of FLS functions related to their pathogenic role in RA.

Adult↗
PubMed1991

[Chemotherapy and immunomodulating treatment of patients with multiple myeloma].

Prospective studies were carried out on the effectiveness of various treatment methods in 208 patients with plasmocytic myeloma. In 102 patients induction therapy was based exclusively on melphalan, in 106 cases polychemotherapy was used including vincristine, melphalan, carmustine, cyclophosphamide and prednisone. The differences in the per cent of patients with good response to treatment and in the survival time after treatment beginning were statistically not significant between these groups which suggests that polychemotherapy begun from the diagnosis of the disease is justified in patients with large mass of the neoplasm and poor prognostic factors. In 45 patients chemotherapy was supported by administration of immunomodulatory agents, including calf thymus extract in 25 cases, levamisole in 18 and interferon in 2. It was observed that maintenance of remission with chemotherapy and with immunomodulatory agents calf thymus extract or levamisole prolonged the survival of the patients. In cases of leucopenia the use of calf thymus extract facilitated chemotherapy by stimulation of myelopoiesis.

Adult↗
PubMed1990

Low dose cytosine arabinoside in the treatment of the primary myelodysplastic syndrome.

23 patients with primary myelodysplastic syndrome was observed in 1982-1988. 8 patients with RAEB and RAEB-t according to FAB criterias were treated with low dose cytosine arabinoside. No complete response and only one partial response +10 months duration was achieved. Treatment had a minor influence on the natural course of disease, and doesn't protect patients from the transformation into acute leukaemias.

Adult↗
PubMed1985

Interindividual phenotypic variations in CLL B lymphocyte maturation indication of different maturation blocks.

Peripheral blood lymphocytes from 8 patients with B-derived chronic lymphocytic leukaemia were stimulated by Staphylococcus aureus bacteria strain Cowan 1 with T cell mitogens PHA or PWM in 5-7 day suspension cultures. For the first group of patients proliferation and maturation tests were performed on T cell enriched and T cell depleted subpopulations, obtained from harvested lymphocytes at the end of cultures by the sheep red cell rosette technique. To re-examine mutual influences of cultivated T and B cells in the second group of experiments, lymphocytes from CLL patients and from 5 healthy individuals were investigated by the use of transmembrane cocultivation system after Feldman and Basten. The proliferative responses to lectin and to bacteria were assessed by 3HTdR-blastic and mitotic indices. The maturation process of B lymphocytes was examined by cytoplasmic Ig, studied by FITC-conjugated antisera. Results obtained with cocultivation system support the view that T cell replacing factor(s) were required for inducing prolonged growth and development of maturation of more numerous B lymphocytes in response to Staphylococcus aureus, a T cell independent, B specific polyclonal stimulator. Results analysed in different patients indicate various degrees of maturation of B cells including their differentiation towards a plasmacytoid cell, accompanied by various proliferative capacities of B and T lymphocytes. This functional analysis reflects the heterogeneity of B-CLL patients group.

Adult↗