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1

NOD1 and NOD2 receptors: integral members of the innate and adaptive immunity system

100%

Antosz H., Osiak M.

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2013

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vol. 60

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issue 3

351-360

EN

NOD-like proteins (NLR) are a specialized group of intracellular receptors, which constitute an essential component of the host innate immune system. They were discovered more than a decade ago, but research on this particular class of microbial detectors is still ongoing to allow for a better understanding of the mechanisms, recognition of microorganisms, transmission of signals, and carrying out the activation of inflammatory signaling pathways. In this review, we discuss the construction of NOD1 and NOD2 receptors, their functions, and significance in the pathogenesis of inflammatory diseases in humans.

2

Metal responsive transcription factor 1 (MTF-1) regulates zinc dependent cellular processes at the molecular level

100%

Grzywacz A., Gdula-Argasińska J., Muszyńska B., Tyszka-Czochara M., Librowski T., Opoka W.

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2015

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vol. 62

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issue 3

491-498

EN

Metal responsive transcription factor 1 (MTF-1) is a zinc dependent transcription factor which is involved in the regulation of intracellular signaling pathways. MTF-1 regulates the expression of two streams of genes functioning in metal homeostasis and anti-oxidative response. MTF-1 acts in the process of binding of toxic metal ions in the cell, due to the activation of the expression of metallothioneins (MTs). Additionally, MTF-1 regulates transcription of genes involved in the sequestration of zinc and its intracellular transport. Disruption of zinc and MT homeostasis has an indispensable influence on the development of several pathological states. Moreover, by increasing MT activity, MTF-1 can effectively protect cells from oxidative and hypoxic stresses. The mechanism of MTF-1 action in cells includes the regulation of the proper immune response through activation/repression of anti- and pro-inflammatory cytokines. MTF-1 function in immune response is related to nuclear factor-κB (NF-κB) activity. Synthesis of insulin is also related to the activity of this transcription factor and zinc balance. Insulin transport also depends on zinc. In pancreatic β-cells, several types of the zinc transporters are found. Zinc transporters coordinated action is crucial for the synthesis and secretion of insulin. Disturbances in the regulation of signaling pathways connected with MTF-1 function can entail further alterations in zinc intracellular status and this growing imbalance can promote the pathophysiology of degenerative disorders.

3

TNFα-induced activation of NFκB protects against UV-induced apoptosis specifically in p53-proficient cells

88%

Szołtysek K., Pietranek K., Kalinowska-Herok M., Pietrowska M., Kimmel M., Widłak P.

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2008

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vol. 55

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issue 4

741-748

EN

The signaling pathways that depend on p53 or NFκB transcription factors are essential components of cellular responses to stress. In general, p53 is involved in either activation of cell cycle arrest or induction of apoptosis, while NFκB exerts mostly anti-apoptotic functions; both regulatory pathways apparently interfere with each other. Here we aimed to analyze the effects of NFκB activation on DNA damage-induced apoptosis, either p53-dependent or p53-independent, in a set of human cell lines. Four cell lines, HCT116 and RKO colon carcinoma, NCI-H1299 lung carcinoma and HL60 myeloblastoma, each of them in two congenic variants either containing or lacking transcriptionally competent p53, were used. Cells were incubated with TNFα cytokine to activate NFκB and then treated with ultraviolet or ionizing radiation to induce apoptosis, which was assessed by measurement of the sub-G1 cell fraction. We observed that treatment with TNFα resulted in a significant reduction in the frequency of apoptotic cells in UV-irradiated p53-proficient lines (with exception of the UV-resistant NCI-H1299 cells). This anti-apoptotic effect was lost when cells were pretreated with parthenolide, an inhibitor of NFκB activation. In marked contrast, TNFα-pretreatment of p53-deficient lines resulted in an increased frequency of apoptotic cells after UV irradiation (with exception of HL60 cells). Such anti- and pro-apoptotic influence of TNFα was less obvious in cells treated with ionizing radiation. The data clearly indicates functional interference of both signaling pathways upon the damage-induced apoptotic response, yet the observed effects are both cell type- and stimulus-specific.

4

The response of L5178Y lymphoma sublines to oxidative stress: Antioxidant defence, iron content and nuclear translocation of the p65 subunit of NF-κB.

75%

Boużyk E., Grądzka I., Iwaneńko T., Kruszewski M., Sochanowicz B., Szumiel I.

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2000

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vol. 47

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issue 4

881-888

EN

We examined the response to hydrogen peroxide of two L5178Y (LY) sublines which are inversely cross-sensitive to hydrogen peroxide and X-rays: LY-R cells are radioresistant and hydrogen peroxide-sensitive, whereas LY-S cells are radiosensitive and hydrogen peroxide-resistant. Higher initial DNA breaks and higher iron content (potentially active in the Fenton reaction) were found in the hydrogen peroxide sensitive LY-R cells than in the hydrogen peroxide resistant LY-S cells, whereas the antioxidant defence of LY-R cells was weaker. In particular, catalase activity is twofold higher in LY-S than in LY-R cells. The content of monobromobimane-reactive thiols is 54% higher in LY-S than in LY-R cells. In contrast, the activity of glutathione peroxidase (GPx) is about two times higher in LY-R than in LY-S cells; however, upon induction with selenium the activity increases 15.6-fold in LY-R cells and 50.3-fold in LY-S cells. Altogether, the sensitivity difference is related to the iron content, the amount of the initial DNA damage, as well as to the efficiency of the antioxidant defence system. Differential nuclear translocation of p65-NF-κB in LY sublines is due to the more efficient antioxidant defence in LY-S than in LY-R cells.

5

Flavanols from Japanese quince (Chaenomeles japonica) fruit suppress expression of cyclooxygenase-2, metalloproteinase-9, and nuclear factor-kappaB in human colon cancer cells

75%

Owczarek K., Hrabec E., Fichna J., Sosnowska D., Koziołkiewicz M., Szymański J., Lewandowska U.

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2017

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vol. 64

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issue 3

567-576

EN

Natural polyphenols and polyphenol-rich extracts have been found to possess preventive and therapeutic potential against several types of cancers, including colorectal cancer (CRC), which is an example of an inflammation-associated cancer. This study examines the chemopreventive effect of a Japanese quince (Chaenomeles japonica) fruit flavanol preparation (JQFFP) on colon cancer SW-480 cells. JQFFP, rich in procyanidin monomers and oligomers, was found to inhibit the SW-480 cell viability by 40% at 150 µM catechin equivalents (CE) after 72 h incubation when compared to control, but it was non-toxic to normal colon fibroblast CCD-18Co cells. Furthermore, 100 µM CE JQFFP suppressed COX-2 mRNA expression to 36.7% of control values and protein expression to 77%. In addition, JQFFP reduced the MMP-9 protein expression (to 24% vs. control at 100 µM CE) and caused inhibition of its enzymatic activity (to 35% vs. control at 100 µM CE). Not only did JQFFP inhibit the COX-2 and MMP-9 levels, but it also reduced the NF-κB protein expression (to 65% of control) and phosphorylation of its p65 subunit (to 51%) at 100 µM CE. These results provide the first evidence that JQFFP inhibits COX-2, MMP-9, and NF-κB expression, suggesting that it has cytotoxic, anti-inflammatory, and anti-metastatic activities towards the colon cancer SW-480 cells.

6

Regulatory effects of 1,25-dihydroxyvitamin D3 on vascular smooth muscle cells

63%

Tukaj S., Trzonkowski P., Tukaj C.

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EN

Inflammatory response has been recognized as a central feature in the development and progression of atherosclerosis, and VSMCs (Vascular Smooth Muscle Cells) - the main cellular component of media, play an important role in this process. Many reports indicate that the biologically active vitamin D metabolite - 1,25-dihydroxyvitamin D3 (1,25(OH)2D3 = calcitriol), besides its well established role in calcium homeostasis, plays an essential role in the regulation of the inflammation process. The aim of this study was to determine the regulatory effects of calcitriol, applied at two supra-physiological doses (10 nM and 100 nM), in VSMC culture. Secretion of the pro-inflammatory cytokines, IL-6 and TNF-α, was significantly attenuated in calcitriol-treated VSMC culture, but the level of anti-inflammatory TGF-β was generally unchanged. Since in advanced atherosclerosis lesions several cell types, including VSMCs, overproduce the HSP70 chaperone protein, we also checked the effects of calcitriol on its synthesis. The presence of 1,25(OH)2D3 did not affect HSP70 synthesis under physiological conditions but the synthesis of HSP70 in VSMCs exposed to heat shock was significantly inhibited by calcitriol (=100 nM). We observed that 1,25(OH)2D3 induced SOD 1 activity, stimulated the expression of IκB-α, and did not influence the level of NF-κB-p65 in VSMCs. The results of our study suggest that 1,25(OH)2D3 may serve as a natural anti-inflammatory agent and may therefore play a beneficial role in the physiology of VSMC in some contexts of atherosclerosis.

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NOD1 and NOD2 receptors: integral members of the innate and adaptive immunity system

Metal responsive transcription factor 1 (MTF-1) regulates zinc dependent cellular processes at the molecular level

TNFα-induced activation of NFκB protects against UV-induced apoptosis specifically in p53-proficient cells

The response of L5178Y lymphoma sublines to oxidative stress: Antioxidant defence, iron content and nuclear translocation of the p65 subunit of NF-κB.

Flavanols from Japanese quince (Chaenomeles japonica) fruit suppress expression of cyclooxygenase-2, metalloproteinase-9, and nuclear factor-kappaB in human colon cancer cells

Regulatory effects of 1,25-dihydroxyvitamin D3 on vascular smooth muscle cells