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Abstract: Background: The active form of vitamin D, 1,25(OH)2D3, exerts important effects on proliferation and differentiation of many cell types, and immunoregulatory activities in particular on T cell-mediated immunity. Aim: The aim of this study was to investigate whether KH 1060, a vitamin D analogue, could decrease tumor necrosis factor-alpha (TNF-α) levels in patients with inflammatory bowel disease (IBD). Methods: PBMC proliferation was determined by [3H]thymidine incorporation. TNF-α levels were measured by ELISA kit; VDR, Bcl-2 and Bax protein levels with Western blot analysis. Results: KH 1060 inhibited PBMC proliferation and decreased TNF-α levels in IBD patients and this effect was synergistic with anti-TNF-α. VDR protein levels were significantly increased by PBMC treatment with KH 1060 or anti-TNF-α or their combination in ulcerative colitis (UC) patients, and decreased in Crohn''s disease (CD) patients, treating the cells with KH 1060. In UC patients an increase in Bcl-2 and Bax levels was observed incubating, PBMC with KH 1060 or anti-TNF-α or their combination. In CD patients a slight decrease in Bcl-2 levels was registered when anti-TNF alone or in association with KH 1060 was used. Bax protein levels were slightly increased in the presence of KH 1060 alone or in combination with anti-TNF. Conclusion: This study shows that KH 1060 acts as an immunomodulator on PBMC, acting as TNF-α inhibitor. This finding provides strong evidence that vitamin D status could be an important regulator of immunity IBD. [Copyright &y& Elsevier]

Abstract: This study tested the hypothesis that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] plays a role in human umbilical vein endothelial cells (HUVEC) cultures. HUVEC were incubated with 10 or 100nM 1,25(OH)2D3 for 24h, in the absence or presence of 40ng/ml tumor necrosis factor-α (TNF-α) or 2ng/ml interleukin-1α (IL-1α). 1,25(OH)2D3 did not affect HUVEC viability and proliferation, while TNF-α, alone or in combination with the hormone, significantly inhibited HUVEC viability. [3H]thymidine incorporation in HUVEC treated with TNF-α or IL-1α significantly decreased, in the absence or in the presence of the hormone, while the levels of vitamin D receptor markedly increased in the presence of 1,25(OH)2D3 alone or associated with TNF-α or IL-1α, in comparison to the control. The noteworthy increase in protein levels of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) induced by TNF-α was significantly decreased after incubation of the cells with 1,25(OH)2D3, this effect not being seen on E-selectin expression. Neither apoptosis nor nuclear translocation of NF-κB, induced in HUVEC by TNF-α was influenced by 1,25(OH)2D3 treatment. [Copyright &y& Elsevier]

Background: Low serum levels of 1,25(OH)(2)D(3) (1,25D), have been associated with aggressive biologic behavior of prostate cancer (PCa). In the present study, we examined the effects of 1,25D and its novel, low-calcemic analog ZK191784 (ZK) on matrix metalloproteinases (MMPs), as well as on intercellular adhesion molecule-1 (ICAM-1) protein levels in human PCa cell lines LNCaP and DU-145., Materials and Methods: Cells were incubated with either vehicle (control), 1,25D or ZK. MMP-2 and MMP-9 activity was determined by gelatin zymography, while ICAM-1 levels were assessed by Western blot analysis and immunocytochemistry., Results: Compared to the controls, 1,25D and ZK caused a marked dose-dependent decrease in the gelatinolytic activity of the MMPs under study, particularly when ZK was used. Likewise, ICAM-1 was down-regulated in the cells incubated with 1,25D or ZK., Conclusion: Vitamin D analogs appear to be involved in the regulation of extracellular MMP activity and membrane adhesion molecule expression. Further studies, both in vitro and in vivo, are needed to define their role as potential therapeutic tools.

The present work is aimed to evaluate the effects of a surface modification process on the biocompatibility of three vanadium-free titanium alloys with biomedical applications interest. Chemical composition of alloys investigated, in weight %, were Ti-7Nb-6Al, Ti-13Nb-13Zr, and Ti-15Zr-4Nb. An easy and economic method intended to improve the biocompatibiblity of these materials consists in a simple thermal treatment at high temperature, 750 degrees C, in air for different times. The significance of modification of the surface properties to the biological response was studied putting in contact both untreated and thermally treated alloys with human cells in culture, Human Umbilical Vein Endothelial Cells (HUVEC) and Human Peripheral Blood Mononuclear Cells (PBMC). The TNF-alpha release data indicate that thermal treatment improves the biological response of the alloys. The notable enhancement of the surface roughness upon oxidation could be related with the observed reduction of the TNF-alpha levels for treated alloys. A different behavior of the two cell lines may be observed, when adhesion molecules (ICAM-1 and VCAM-1 in HUVEC, ICAM-1, and LFA-1 in PBMC) were determined, PBMC being more sensitive than HUVEC to the contact with the samples. The data also distinguish surface composition and corrosion resistance as significant parameters for the biological response., ((c) 2009 Wiley Periodicals, Inc.)

Crohn's disease (CD) is an inflammatory disease characterized by the activation of the immune system in the gut. Since tumor necrosis factor (TNF-alpha) plays an important role in the initiation and perpetuation of intestinal inflammation in CD, we investigated whether TX 527 [19-nor-14,20-bisepi-23-yne-1,25(OH)(2)D(3)], a Vitamin D analogue, could affect peripheral blood mononuclear cells (PBMC) proliferation and exert an immunosuppressive effect on TNF-alpha production in CD patients, and whether this immunosuppressive action could be mediated by NF-kappaB down-regulation. TX 527 significantly decreased cell proliferation and TNF-alpha levels. On activation, NF-kappaB, rapidly released from its cytoplasmatic inhibitor (IKB-alpha), transmigrates into the nucleus and binds to DNA response elements in gene promoter regions. The activation of NF-kappaB, stimulated by TNF-alpha, and its nuclear translocation together with the degradation of IKB-alpha were blocked by TX 527. At the same time, NF-kappaB protein levels present in cytoplasmic extracts decreased in the presence of TNF-alpha and increased when PBMC were incubated with TX 527. The results of our studies indicate that TX 527 inhibits TNF-alpha mediated effects on PBMC and the activation of NF-kappaB and that its action is mediated by Vitamin D receptor (VDR), which is activated when the cells are stimulated with TX 527.