The Experts below are selected from a list of 54 Experts worldwide ranked by ideXlab platform

F Chytil - One of the best experts on this subject based on the ideXlab platform.

  • Effect of retinoids on nuclear retinoic acid receptors mRNA in adipose tissue of retinol-deficient rats.
    Journal of lipid research, 1992
    Co-Authors: Riaz-ul-haq, F Chytil
    Abstract:

    In this study, we examined effects of retinol deficiency and three retinoids, all-trunsretinoic acid, 134s retinoic acid, and Etretin, the aromatic derivative of retinoic acid, on nuclear retinoic acid receptor isoforms CL, p, and y mRNA in rat adipose tissue. Retinol deficiency caused an al- most 50% decrease in isoform p mRNA levels of adipose tis- sue, whereas little change occurred in the abundance of CL and y isoforms transcripts in this tissue. Intragastric ad- ministration of all-trunsretinoic acid to retinoldeficient rats increased the adipose tissue retinoic acid receptor isoforms p and y mRNA levels sixfold and twofold, respectively, in 4 h as compared to adipose tissue of retinoldeficient rats that were administered cottonseed oil. In contrast to this, 13-cis retinoic acid and Etretin at equimolar doses were not effec- tive in inducing p or y isoforms mRNA in retinoldeficient rats. m These results show that adipose tissue isoform p responds to retinol deficiency, and all-trunsretinoic acid rapidly induces p and y mRNA isoforms in this tissue. Thus, retinoic acid may regulate expression of specific genes through its interaction with retinoic acid receptors in adipo- cytes.-Haq, R. U., and F. Chytil. Effect of retinoids on

  • Effect of retinoids on nuclear retinoic acid receptors mRNA in adipose tissue of retinol-deficient rats.
    Journal of lipid research, 1992
    Co-Authors: Riaz-ul-haq, F Chytil
    Abstract:

    In this study, we examined effects of retinol deficiency and three retinoids, all-trans-retinoic acid, 13-cis-retinoic acid, and Etretin, the aromatic derivative of retinoic acid on nuclear retinoic acid receptor isoforms alpha, beta, and gamma mRNA in rat adipose tissue. Retinol deficiency caused an almost 50% decrease in isoform beta mRNA levels of adipose tissue, whereas little change occurred in the abundance of alpha and gamma isoforms transcripts in this tissue. Intragastric administration of all-trans-retinoic acid to retinol-deficient rats increased the adipose tissue retinoic acid receptor isoforms beta and gamma mRNA levels sixfold and twofold, respectively, in 4 h as compared to adipose tissue of retinol-deficient rats that were administered cottonseed oil. In contrast to this, 13-cis-retinoic acid and Etretin at equimolar doses were not effective in inducing beta or gamma isoforms mRNA in retinol-deficient rats. These results show that adipose tissue isoform beta responds to retinol deficiency, and all-trans-retinoic acid rapidly induces beta and gamma mRNA isoforms in this tissue. Thus, retinoic acid may regulate expression of specific genes through its interaction with retinoic acid receptors in adipocytes.

  • Differential effects of all-trans and 13-cis-retinoic acid on mRNA levels of nuclear retinoic acid receptors in rat lung and liver.
    Biochemical and biophysical research communications, 1991
    Co-Authors: Riaz-ul-haq, Magnus Pfahl, F Chytil
    Abstract:

    Summary The effects of three retinoids, all-trans-retinoic acid (all- trans -RA), 13- cis -RA, and Etretin were examined on mRNA abundance of nuclear retinoic acid receptors (RAR- α , β , and γ ) in lung and liver of retinol deficient and chow fed rats. All- trans -RA increased lung RAR- β mRNA levels 5 or 11-fold in chow fed and retinol deficient rats, respectively. Similarly to lung, liver RAR- β mRNA levels were 3-fold higher in retinol deficient rats fed all- trans -RA than the rats fed cottonseed oil. Lung RAR- γ mRNA levels were also induced 2-fold by all- trans -RA. In contrast to this, 13- cis -RA and Etretin at equimolar doses failed to enhance lung or liver RAR- β or lung RAR- γ mRNA levels in retinol deficient rats. These data for the first time show that all- trans -RA is more effective than its 13- cis -isomer in regulating the expression of RAR- β and γ transcripts in adult animal.

Riaz-ul-haq - One of the best experts on this subject based on the ideXlab platform.

  • Effect of retinoids on nuclear retinoic acid receptors mRNA in adipose tissue of retinol-deficient rats.
    Journal of lipid research, 1992
    Co-Authors: Riaz-ul-haq, F Chytil
    Abstract:

    In this study, we examined effects of retinol deficiency and three retinoids, all-trunsretinoic acid, 134s retinoic acid, and Etretin, the aromatic derivative of retinoic acid, on nuclear retinoic acid receptor isoforms CL, p, and y mRNA in rat adipose tissue. Retinol deficiency caused an al- most 50% decrease in isoform p mRNA levels of adipose tis- sue, whereas little change occurred in the abundance of CL and y isoforms transcripts in this tissue. Intragastric ad- ministration of all-trunsretinoic acid to retinoldeficient rats increased the adipose tissue retinoic acid receptor isoforms p and y mRNA levels sixfold and twofold, respectively, in 4 h as compared to adipose tissue of retinoldeficient rats that were administered cottonseed oil. In contrast to this, 13-cis retinoic acid and Etretin at equimolar doses were not effec- tive in inducing p or y isoforms mRNA in retinoldeficient rats. m These results show that adipose tissue isoform p responds to retinol deficiency, and all-trunsretinoic acid rapidly induces p and y mRNA isoforms in this tissue. Thus, retinoic acid may regulate expression of specific genes through its interaction with retinoic acid receptors in adipo- cytes.-Haq, R. U., and F. Chytil. Effect of retinoids on

  • Effect of retinoids on nuclear retinoic acid receptors mRNA in adipose tissue of retinol-deficient rats.
    Journal of lipid research, 1992
    Co-Authors: Riaz-ul-haq, F Chytil
    Abstract:

    In this study, we examined effects of retinol deficiency and three retinoids, all-trans-retinoic acid, 13-cis-retinoic acid, and Etretin, the aromatic derivative of retinoic acid on nuclear retinoic acid receptor isoforms alpha, beta, and gamma mRNA in rat adipose tissue. Retinol deficiency caused an almost 50% decrease in isoform beta mRNA levels of adipose tissue, whereas little change occurred in the abundance of alpha and gamma isoforms transcripts in this tissue. Intragastric administration of all-trans-retinoic acid to retinol-deficient rats increased the adipose tissue retinoic acid receptor isoforms beta and gamma mRNA levels sixfold and twofold, respectively, in 4 h as compared to adipose tissue of retinol-deficient rats that were administered cottonseed oil. In contrast to this, 13-cis-retinoic acid and Etretin at equimolar doses were not effective in inducing beta or gamma isoforms mRNA in retinol-deficient rats. These results show that adipose tissue isoform beta responds to retinol deficiency, and all-trans-retinoic acid rapidly induces beta and gamma mRNA isoforms in this tissue. Thus, retinoic acid may regulate expression of specific genes through its interaction with retinoic acid receptors in adipocytes.

  • Differential effects of all-trans and 13-cis-retinoic acid on mRNA levels of nuclear retinoic acid receptors in rat lung and liver.
    Biochemical and biophysical research communications, 1991
    Co-Authors: Riaz-ul-haq, Magnus Pfahl, F Chytil
    Abstract:

    Summary The effects of three retinoids, all-trans-retinoic acid (all- trans -RA), 13- cis -RA, and Etretin were examined on mRNA abundance of nuclear retinoic acid receptors (RAR- α , β , and γ ) in lung and liver of retinol deficient and chow fed rats. All- trans -RA increased lung RAR- β mRNA levels 5 or 11-fold in chow fed and retinol deficient rats, respectively. Similarly to lung, liver RAR- β mRNA levels were 3-fold higher in retinol deficient rats fed all- trans -RA than the rats fed cottonseed oil. Lung RAR- γ mRNA levels were also induced 2-fold by all- trans -RA. In contrast to this, 13- cis -RA and Etretin at equimolar doses failed to enhance lung or liver RAR- β or lung RAR- γ mRNA levels in retinol deficient rats. These data for the first time show that all- trans -RA is more effective than its 13- cis -isomer in regulating the expression of RAR- β and γ transcripts in adult animal.

David A. Norris - One of the best experts on this subject based on the ideXlab platform.

  • The State of Differentiation of Cultured Human Keratinocytes Determines the Level of Intercellular Adhesion Molecule-1 (ICAM-1) Expression Induced by γ Interferon
    The Journal of investigative dermatology, 1992
    Co-Authors: Mari Kashihara-sawami, David A. Norris
    Abstract:

    Inducing the expression of ICAM-1(CD54) on the surface of epidermal keratinocytes is an important step, in initiating leukocyte interaction with the epidermis. We studied tile effect of keratinocyte differentiation and of drugs used to treat epidermal inflammation on the induction of this important adhesion molecule. Cell membrane expression of ICAM-1 in cultured human keratinocytes was analyzed using both immunofluorescence and FACS analysis of staining with anti-ICAM-1 monoclonal antibody and was correlated with markers of keratinocyte differentiation. Cell-surface ICAM-I expression was induced by 7 interferon in all culture conditions, but was significantly greater (p Anti-inflammatory glucocorticoids had no effect on ICAM-1 expression in cultured human keratinocytes, even at suboptimal γ interferon doses (5 U/ml). β-estradiol, on the other hand, mimicked the Etretin effect, increasing both IFN induction of ICAM-1 expression and K5 staining in more differentiated keratinocytes in 0.15 and 1.0 nM calcium, but not in those in 0.03 mM calcium. Both Etretin and β-estradiol decreased staining of involucrin, a marker of terminal differentiation, supporting the proposition that in this experimental system these drugs suppress keratinocyte differentiation. The enhanced ICAM-1 induction in keratinocytes with a basal level of differentiation correlates with the in vivo effects of interferon on ICAM-1 and may be a principal determinant in the patterns of ICAM-1 seen in inflammatory skin diseases.

Mari Kashihara-sawami - One of the best experts on this subject based on the ideXlab platform.

  • The State of Differentiation of Cultured Human Keratinocytes Determines the Level of Intercellular Adhesion Molecule-1 (ICAM-1) Expression Induced by γ Interferon
    The Journal of investigative dermatology, 1992
    Co-Authors: Mari Kashihara-sawami, David A. Norris
    Abstract:

    Inducing the expression of ICAM-1(CD54) on the surface of epidermal keratinocytes is an important step, in initiating leukocyte interaction with the epidermis. We studied tile effect of keratinocyte differentiation and of drugs used to treat epidermal inflammation on the induction of this important adhesion molecule. Cell membrane expression of ICAM-1 in cultured human keratinocytes was analyzed using both immunofluorescence and FACS analysis of staining with anti-ICAM-1 monoclonal antibody and was correlated with markers of keratinocyte differentiation. Cell-surface ICAM-I expression was induced by 7 interferon in all culture conditions, but was significantly greater (p Anti-inflammatory glucocorticoids had no effect on ICAM-1 expression in cultured human keratinocytes, even at suboptimal γ interferon doses (5 U/ml). β-estradiol, on the other hand, mimicked the Etretin effect, increasing both IFN induction of ICAM-1 expression and K5 staining in more differentiated keratinocytes in 0.15 and 1.0 nM calcium, but not in those in 0.03 mM calcium. Both Etretin and β-estradiol decreased staining of involucrin, a marker of terminal differentiation, supporting the proposition that in this experimental system these drugs suppress keratinocyte differentiation. The enhanced ICAM-1 induction in keratinocytes with a basal level of differentiation correlates with the in vivo effects of interferon on ICAM-1 and may be a principal determinant in the patterns of ICAM-1 seen in inflammatory skin diseases.

C. E. Orfanos - One of the best experts on this subject based on the ideXlab platform.

  • Cultivation of human dermal microvascular endothelial cells in vitro: Immunocytochemical and ultrastructural characterization and effect of treatment with three synthetic retinoids
    Archives of Dermatological Research, 1991
    Co-Authors: E. Imcke, Zb. Ruszczak, A. Mayer-da Silva, M. Detmar, C. E. Orfanos
    Abstract:

    A new reliable and reproducible technique to culture endothelial cells from the small vessels and capillaries of human skin is introduced, and proliferation and differentiation of the growing cells are characterized. The endothelial origin of the culture cells was confirmed by light- and electron microscopy and by labelling with Ulex europaeus Agglutinin I and an antibody against Factor VIII-related antigen. Further immunocytochemical characterization showed that 92–100% of the cells were positive for Β _2-microglobulin and the entire cell population expressed vimentin, whereas cytokeratins, desmin, HLA-DR antigen, Leu 6 and S 100 protein, could not be detected. As vascular endothelium is a common site of inflammation and retinoids have been shown to be of good clinical efficacy in some chronic inflammatory skin diseases, we investigated the influence of Etretinate, Etretin and isotretinoin on proliferation and antigen expression of our culture cells. All retinoids applied inhibited proliferation of endothelial cells in a dose- and time-dependent manner whereas they induced neither HLA-DR nor intercellular adhesion molecule-1 (ICAM-1). Furthermore, none of the retinoids applied influenced the γ-interferon-induced expression of these surface antigens on endothelial cells. Our results suggest that the action of retinoids in skin inflammation is not mediated by modulation of HLA-DR or ICAM-1. The cell culture technique described here is an interesting and reliable model for studying the influence of drugs on endothelial cell growth and differentiation in vitro.