M Stio

University of Florence, Florens, Tuscany, Italy

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Publications (50)129.44 Total impact

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    ABSTRACT: Background and aim The adhesion molecule expression and matrix metalloproteinases (MMPs) are proposed to be major factors for intestinal injury mediated by T cells in (IBD) and are up-regulated in intestinal mucosa of IBD patients. To investigate the effect of vitamin D derivatives on adhesion molecules and MMPs in colonic biopsies of IBD patients. Methods Biopsies from inflamed and non-inflamed tract of terminal ileum and colon and PBMC from the same IBD patients were cultured with or without vitamin D derivatives. MMP activity and adhesion molecule levels were determined. Results 1,25(OH)2D3 and ZK 191784 significantly decrease ICAM-1 protein levels in the biopsies obtained only from the inflamed region of intestine of UC patients, while MAdCAM-1 levels decrease in the presence of 1,25(OH)2D3 in the non-inflamed region, and, in the presence of ZK, in the inflamed one. In CD patients 1,25(OH)2D3 and ZK decrease ICAM-1 and MAdCAM-1 in the biopsies obtained from the non-inflamed and inflamed regions, with the exception of ICAM-1 in the inflamed region in the presence of 1,25(OH)2D3. The expression of MMP-9, MMP-2, and MMP-3 decreases in the presence of vitamin D derivatives in UC and CD with the exception of 1,25(OH)2D3 that does not affect the levels of MMP-9 and MMP-2 in CD. Vitamin D derivatives always affect MMP-9, MMP-2 and ICAM-1 in PBMC of UC and CD patients. Conclusions Based on the increased expression of ICAM-1, MAdCAM-1 and MMP-2,-9,-3 in IBD, our study suggests that vitamin D derivatives may be effective in the management of these diseases.
    Journal of Crohn s and Colitis 09/2014; · 3.39 Impact Factor
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    ABSTRACT: The biocompatibility of austenitic stainless steels can be improved by means of surface engineering techniques. In the present research it was investigated if low temperature nitrided AISI 316L austenitic stainless steel may be a suitable substrate for bioactive protein coating consisting of collagen-I. The biocompatibility of surface modified alloy was studied using as experimental model endothelial cells (human umbilical vein endothelial cells) in culture. Low temperature nitriding produces modified surface layers consisting mainly of S phase, the supersaturated interstitial solid solution of nitrogen in the austenite lattice, which allows to enhance surface microhardness and corrosion resistance in PBS solution. The nitriding treatment seems to promote the coating with collagen-I, without chemical coupling agents, in respect of the untreated alloy. For biocompatibility studies, proliferation, lactate dehydrogenase levels and secretion of two metalloproteinases (MMP-2 and MMP-9) were determined. Experimental results suggest that the collagen protection may be favourable for endothelial cell proliferation and for the control of MMP-2 release.
    Journal of Materials Science Materials in Medicine 03/2013; · 2.14 Impact Factor
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    ABSTRACT: 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. 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. 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. 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.
    Anticancer research 12/2011; 31(12):4091-8. · 1.71 Impact Factor
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    ABSTRACT: A comprehensive study on glutathione metabolism in rat heart and liver as a function of age was performed. In the heart, reduced glutathione, total glutathione, and the glutathione redox index showed a decrease during aging, while oxidized glutathione levels increased in 5-month-old rats with respect to the young animals and remained quite constant in 14- and 27-month-old rats. In the liver, the highest levels of reduced glutathione were found in the 2-month-old rats, while oxidized glutathione reached a peak at 5 months. Glutathione-associated enzymes showed age-related changes. Glutathione peroxidase, unaffected by aging in the heart, decreased in the liver of the 27-month-old rats. In the heart and the liver, the highest values of glutathione S-transferase were found at 5 months and 27 months, respectively. Glucose-6-phosphate dehydrogenase followed a similar trend in both heart and liver. Glutathione reductase also showed the same behaviour in heart and in liver, increasing in old rats with respect to the other age groups. A decrease in gamma-glutamylcysteine synthetase was found in the heart and liver of 27-month-old rats in comparison with the 2-month-old ones. In conclusion, a decreased antioxidant capability has been demonstrated in both heart and liver of old rats.
    Biochemistry and Cell Biology 01/2011; 72(1-2):58-61. · 2.92 Impact Factor
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    ABSTRACT: Intracellular adhesion molecules and matrix metalloproteinases (MMPs) are up-regulated in intestinal mucosa of patients with inflammatory bowel diseases (IBD), i.e. ulcerative colitis (UC) or Crohn's disease (CD). Our aim was to verify whether the vitamin D analogue ZK 156979 (ZK) down-regulates adhesion molecules, and decreases MMPs production by PBMC of IBD patients. ICAM-1 and LFA-1 levels increase, when PBMC were incubated with PHA or LPS or TNF-alpha, and decrease when these substances were used in combination with ZK. MMPs activity increases incubating the cells with PHA or LPS or TNF-alpha. MMP-9 decreases when ZK was used in association, while MMP-2 decreases only when ZK was used in combination with anti-TNF-alpha. Our results suggest that the down-regulation of ICAM-1 and LFA-1 on PBMC and the inhibition of MMP-9 activity by ZK could provide a potential role of this low calcemic vitamin D derivative in future strategies in IBD therapy.
    Clinical Immunology 07/2010; 136(1):51-60. · 3.77 Impact Factor
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    ABSTRACT: In the present work, X-ray photoelectron spectroscopy (XPS) was used to study the surface chemical composition of three alloys for biomedical applications: Ti–7Nb–6Al, Ti–13Nb–13Zr and Ti–15Zr–4Nb. The surface of these alloys was modified by annealing in air at 750°C for different times with the aim of developing an oxide thick layer on top. The evolution of surface composition with annealing time was studied by XPS, and compared with the composition of the native oxide layer present on the samples before annealing. Two different oxidation trends were observed depending on the alloying elements and their corresponding diffusion kinetics, which give rise to different chemical species at the topmost layers. These results were linked with an evaluation of the biological response of the alloys by bringing them in contact with human peripheral blood mononuclear cells (PBMC).
    Materials Science and Engineering C 04/2010; 30(3):465-471. · 2.74 Impact Factor
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    ABSTRACT: 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.
    Journal of Biomedical Materials Research Part A 06/2009; 92(4):1623-34. · 2.83 Impact Factor
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    ABSTRACT: Lymphocytes are crucial in the pathogenesis of inflammatory bowel disease (IBD) and are an important target for drug development. Our aim was to verify whether 2 vitamin D derivatives, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and EB 1089, could induce cell apoptosis and affect cell-cell interaction by regulating adhesion molecule levels. Peripheral blood mononuclear cell (PBMC) proliferation was studied by [3H]thymidine incorporation and apoptosis was determined using an enzyme-linked immunosorbent assay (ELISA) kit. (Poly(ADP-ribose)polymerase (PARP) cleavage, caspase-3, and ICAM-1 protein levels were determined by Western blot analysis. Our results indicate that 1,25(OH)2D3 or EB 1089 or anti-TNF-alpha (infliximab) induce apoptosis in PBMC obtained from healthy subjects. In IBD patients apoptosis is induced by vitamin D derivatives and by anti-TNF-alpha only in CD patients. Caspase-3 activation and PARP cleavage are registered when PBMC were treated with vitamin D derivatives. ICAM-1 levels remarkably increase when PBMC was incubated with lipopolysaccharide (LPS) or TNF-alpha. The treatment with the vitamin D derivatives, alone or in combination with LPS or TNF-alpha, significantly decreases ICAM-1 levels both in healthy subjects and IBD patients. In HUVEC cocultured with PBMC, previously incubated with LPS or TNF-alpha associated with 1,25(OH)2D3, ICAM-1 levels decrease both in healthy subjects and IBD patients. 1,25(OH)2D3 and EB 1089 inhibit PBMC proliferation, induce apoptosis in PBMC of healthy subjects and IBD patients, and affect ICAM-1 expression on PBMC and on HUVEC cocultured with PBMC, suggesting that the ICAM-1 downregulation could provide a new target for controlling the recruitment of leukocytes at the sites of inflammation in IBD.
    Inflammatory Bowel Diseases 06/2008; 14(5):597-604. · 5.12 Impact Factor
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    ABSTRACT: 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.
    The Journal of Steroid Biochemistry and Molecular Biology 02/2007; 103(1):51-60. · 3.98 Impact Factor
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    ABSTRACT: The effects of AISI 316L austenitic stainless steel, tested in untreated state or subjected to glow-discharge nitriding (at 10 or 20 hPa) and nitriding + post-oxidizing treatments, on human umbilical vein endothelial cells (HUVEC) and on peripheral blood mononuclear cells (PBMC) were evaluated. All the treated samples showed a better corrosion resistance in PBS and higher surface hardness in comparison with the untreated alloy. In HUVEC put in contact for 72 h with the sample types, proliferation and apoptosis decreased and increased, respectively, in the presence of the nitrided + post-oxidized samples, while only slight differences in cytokine (TNF-alpha, IL-6, and TGF-beta1) release were registered. Intercellular adhesion molecule-1 (ICAM-1) increased in HUVEC incubated with all the treated samples, while vascular cell adhesion molecule-1 (VCAM-1) and E-selectin increased in the presence of all the sample types. PBMC incubated for 48 h with the samples showed a decrease in proliferation and an increase in apoptosis in the presence of the untreated samples and the nitrided + post-oxidized ones. All the sample types induced a remarkable increase in TNF-alpha and IL-6 release in PBMC culture medium, while only the untreated sample and the nitrided at 10 hPa induced an increase in ICAM-1 expression. In HUVEC cocultured with PBMC, previously put in contact with the treated AISI 316L samples, increased levels of ICAM-1 were detected. In HUVEC coincubated with the culture medium of PBMC, previously put in contact with the samples under study, a noteworthy increase in ICAM-1, VCAM-1, and E-selectin levels was always registered, with the exception of VCAM-1, which was not affected by the untreated sample. In conclusion, even if the treated samples do not show a marked increase in biocompatibility in comparison with the untreated alloy, their higher corrosion resistance may suggest a better performance as the contact with physiological environment becomes longer.
    Journal of Biomedical Materials Research Part A 02/2007; 80(1):131-45. · 2.83 Impact Factor
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    ABSTRACT: The active form of vitamin D, 1,25(OH)(2)D(3), exerts important effects on proliferation and differentiation of many cell types, and immunoregulatory activities in particular on T cell-mediated immunity. The aim of this study was to investigate whether KH 1060, a vitamin D analogue, could decrease tumor necrosis factor-alpha (TNF-alpha) levels in patients with inflammatory bowel disease (IBD). PBMC proliferation was determined by [(3)H]thymidine incorporation. TNF-alpha levels were measured by ELISA kit; VDR, Bcl-2 and Bax protein levels with Western blot analysis. KH 1060 inhibited PBMC proliferation and decreased TNF-alpha levels in IBD patients and this effect was synergistic with anti-TNF-alpha. VDR protein levels were significantly increased by PBMC treatment with KH 1060 or anti-TNF-alpha 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-alpha 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. This study shows that KH 1060 acts as an immunomodulator on PBMC, acting as TNF-alpha inhibitor. This finding provides strong evidence that vitamin D status could be an important regulator of immunity IBD.
    International Immunopharmacology 08/2006; 6(7):1083-92. · 2.42 Impact Factor
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    ABSTRACT: This study tested the hypothesis that 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] plays a role in human umbilical vein endothelial cells (HUVEC) cultures. HUVEC were incubated with 10 or 100 nM 1,25(OH)(2)D(3) for 24 h, in the absence or presence of 40 ng/ml tumor necrosis factor-alpha (TNF-alpha) or 2 ng/ml interleukin-1alpha (IL-1alpha). 1,25(OH)(2)D(3) did not affect HUVEC viability and proliferation, while TNF-alpha, alone or in combination with the hormone, significantly inhibited HUVEC viability. [(3)H]thymidine incorporation in HUVEC treated with TNF-alpha or IL-1alpha 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)(2)D(3) alone or associated with TNF-alpha or IL-1alpha, 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-alpha was significantly decreased after incubation of the cells with 1,25(OH)(2)D(3), this effect not being seen on E-selectin expression. Neither apoptosis nor nuclear translocation of NF-kappaB, induced in HUVEC by TNF-alpha was influenced by 1,25(OH)(2)D(3) treatment.
    Cell Biology International 05/2006; 30(4):365-75. · 1.64 Impact Factor
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    ABSTRACT: The Ti-6Al-4V titanium alloy is widely employed as an implant material. The effects of Ti-6Al-4V samples, tested in both an untreated state and one in which the samples were subjected to a glow-discharge treatment performed with the use of air, on human peripheral blood mononuclear cells (PBMC) were studied. Apoptosis, undetectable after 24-h contact of PBMC with the two sample types, is induced after 48 h by treated samples, and, after 48 h, but in the presence of 1.5 microg/mL PHA, by both sample types. The expression of intercellular adhesion molecule-1 (ICAM-1) always increases, in comparison with control, in PBMC put in contact with the two sample types. In the same way, a remarkable increase in tumor necrosis-alpha (TNF-alpha) release in the culture medium is registered, when PBMC are put in contact with the two sample types for 24 and 48 h. Human umbilical-vein endothelial cells (HUVEC) cocultured for 48 h with PBMC, previously incubated with the two sample types for 24 h, show an increase in ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1) protein expression in comparison with control (HUVEC cocultured with control PBMC), indicating that inflammatory phenomena might occur. Taken together, these results suggest that, although plasma-treated titanium alloy shows a better biocompatibility in comparison with the untreated one, attention must be paid to the careful control of the first signs of inflammation.
    Journal of Biomedical Materials Research Part A 09/2005; 74(2):197-207. · 2.83 Impact Factor
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    ABSTRACT: The aim of this study was to investigate whether the vitamin D analogue KH 1060 could exert a suppressive action on Tumor necrosis factor-alpha (TNF-alpha). The chimeric anti-TNF-alpha monoclonal antibody (anti-TNF), alone or in combination with KH 1060, was also used. KH 1060 (0.01, 0.1, 1 nM) significantly inhibited cell proliferation, determined after 5 days by [3H]thymidine incorporation, when peripheral blood mononuclear cells (PBMC), obtained from healthy subjects, were stimulated with phytohaemagglutinin (PHA) and incubated for 24 h in the absence and in the presence of lipopolysaccharide (LPS). In the same experimental conditions, anti-TNF exerted a significant inhibition on PBMC proliferation, at the lowest doses (0.001, 0.01 microg/ml) in the absence of LPS, and at 0.001, 1, 10 microg/ml in its presence. A synergistic inhibition was registered combining KH 1060 and anti-TNF, at well-defined concentrations. 0.1 nM KH 1060 produced a significant decrease in TNF-alpha levels, determined by ELISA, although less remarkable than in the presence of anti-TNF. This decrease was synergistic, associating 0.1 nM KH 1060 and 0.1 microg/ml anti-TNF. VDR protein levels were increased by 0.1 nM KH 1060, 0.1 microg/ml anti-TNF or their combination. The protein levels of two oncogenes, Bax and Bcl-2, remained unchanged, when PBMC were incubated with KH 1060, anti-TNF or their combination in the absence of LPS, while, in its presence, an increase was registered. The demonstrated anti-TNF-alpha effect of KH 1060 may suggest for this compound an immunosuppressive action and the possibility to synergistically act with other drugs.
    International Immunopharmacology 05/2005; 5(4):649-59. · 2.42 Impact Factor
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    ABSTRACT: Among the titanium alloys employed as implant materials, the Ti-6Al-4V alloy is still widely used. Ti-6Al-4V titanium alloy samples, in untreated state and subjected to treatments in air by furnace or glow-discharge processes, were put in contact with human umbilical vein endothelial cells (HUVEC) in order to evaluate their effects on biocompatibility. In HUVEC kept for 48 h in the presence of the three sample types neither cell proliferation nor protein content nor lactate dehydrogenase release in the culture medium are affected, while apoptosis is induced after 48- and 96-h contact of the cells with the untreated sample type, and after 96-h contact with the plasma treated one, the furnace treated sample type being ineffective. The expression of two adhesion molecules, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was also studied. The incubation of HUVEC with the three sample types for 48 or 96 h induces a significant increase in ICAM-1 protein levels, in comparison with control cells, while VCAM-1 expression is not detectable. In the same way, TNF-alpha release in the culture medium, assayed after 48- and 96-h contact of the cells with the three sample types, is significantly higher, in comparison with control, even if the highest values are registered in the presence of the untreated samples. Taken together, these data indicate that, although Ti-6Al-4V alloy samples, and in particular the treated ones, show a good biocompatibility, attention must be given to the first signs of inflammation.
    Acta Biomaterialia 04/2005; 1(2):223-34. · 5.68 Impact Factor
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    ABSTRACT: Infliximab treatment demonstrated clinical and endoscopic benefits in active refractory and fistulizing Crohn's disease. The aim of this research was to investigate the proliferative response of peripheral blood mononuclear cells (PBMC) obtained from patients with active and fistulizing Crohn's disease treated with infliximab therapy. PBMC proliferation and VDR protein levels were also studied when 1,25(OH)2D3 or its analogues (EB 1089, KH 1060) were added to cells cultures. At day 5 of culture, the proliferation of PBMC obtained from patients responsive to the therapy showed a remarkable decrease (about 60%) at T6 (after two infusions) with respect to T0 (before the first infusion). On the contrary, in the unresponsive patient, the proliferative response was four times higher at T6 in comparison with T0. Vitamin D derivatives induced a decrease in cell proliferation higher in responsive patients than in the unresponsive one. Increased VDR levels during therapy were registered only in the unresponsive patient. Our results indicate that PBMC proliferation and VDR expression may be useful indicators to predict the response of patients with Crohn's disease to the infliximab therapy.
    Digestive Diseases and Sciences 03/2004; 49(2):328-35. · 2.26 Impact Factor
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    ABSTRACT: 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3], the hormonal active form of vitamin D3, could represent a potentially therapeutic agent in autoimmune diseases. Cyclosporin A (CsA) shows immunoregulatory properties, which, in many respects, seem to be similar to those of 1,25(OH)2D3. Our aim was to investigate the possible synergistic effect exerted by CsA in combination with 1,25(OH)2D3 or its nonhypercalcemic analogues, EB 1089 and KH 1060, on the proliferative response of T lymphocytes obtained from active ulcerative colitis patients. The T lymphocyte-enriched population was treated with phytohemagglutinin and CsA (doses from 1 ng to 1000 ng/ml) alone or in association with 1,25(OH)2D3 or EB 1089 or KH 1060 (0.1, 1, 10 nM final concentration). Cell proliferation was determined by [3H]thymidine incorporation and analyzed on day 5 of culture. After incubation with CsA, T lymphocyte proliferation was significantly inhibited in comparison with the vehicle-treated cultures. However, T lymphocytes from ulcerative colitis patients were significantly more sensitive to CsA than those from healthy controls. The inhibition in T lymphocyte proliferation, after treatment of the cultures with CsA associated with either 1,25(OH)2D3 or EB 1089 or KH 1060, was synergistic at well-defined concentrations. Taking into account the lowest CsA dose (1 ng/ml), the highest synergistic inhibition in the proliferation of T lymphocytes prepared from ulcerative colitis patients was found combining CsA and 10 nM of 1,25(OH)2D3 or 10 nM of EB 1089 or KH 1060 at the three concentrations. The results obtained, associating the lowest CsA dose and the lowest KH 1060 concentration, may suggest an alternative therapeutic approach in these patients, reducing the dose, and consequently the toxicity, of CsA.
    The American Journal of Gastroenterology 04/2002; 97(3):679-89. · 9.21 Impact Factor
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    ABSTRACT: The response of C2C12 myoblasts to 1 nM 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], two vitamin D analogues (KH 1060 and EB 1089, which are 20-epi-22-oxa and 22,24-diene-analogues, respectively), 100 nM retinoids (9-cis retinoic acid, all-trans retinoic acid) and to combination treatments, after 72 h incubation, was studied. The incubation with 1,25(OH)2D3 was ineffective on either cell proliferation or [3H]thymidine incorporation (expressed as DPM per cell) or protein content per cell. On the contrary, all the other treatments inhibited cell proliferation, this inhibition being synergistic when the vitamin D derivatives were combined with 9-cis or all-trans retinoic acid, and increased [3H]thymidine incorporation and protein content per cell. The levels of the VDR protein remarkably increased in comparison with control cells, except for the incubation with 9-cis retinoic acid. This increase was particularly accentuated in C2C12 cells treated with KH 1060 and 9-cis retinoic acid in combination. These results, taken together, suggest a role for vitamin D derivatives and retinoids on C2C12 cells.
    International Union of Biochemistry and Molecular Biology Life 04/2002; 53(3):175-81. · 2.79 Impact Factor
  • Digestive and Liver Disease - DIG LIVER DIS. 01/2002; 34.
  • The American Journal of Gastroenterology 09/2001; 96(9). · 9.21 Impact Factor