ABSTRACT
Atopic dermatitis (AD) affects adults and children and has a negative impact on quality of life. The present multicentre randomized double-blind controlled trial showed a barrier-improving cream (5% urea) to be superior to a reference cream in preventing eczema relapse in patients with AD (hazard ratio 0.634, p = 0.011). The risk of eczema relapse was reduced by 37% (95% confidence interval (95% CI) 10-55%). Median time to relapse in the test cream group and in the reference cream group was 22 days and 15 days, respectively (p = 0.013). At 6 months 26% of the patients in the test cream group were still eczema free, compared with 10% in the reference cream group. Thus, the barrier-improving cream significantly prolonged the eczema-free time compared with the reference cream and decreased the risk of eczema relapse. The test cream was well tolerated in patients with AD.
Subject(s)
Dermatitis, Atopic/diagnosis , Dermatitis, Atopic/drug therapy , Dermatologic Agents/administration & dosage , Emollients/administration & dosage , Quality of Life , Administration, Cutaneous , Adolescent , Adult , Aged , Aged, 80 and over , Cross-Over Studies , Dermatitis, Atopic/psychology , Double-Blind Method , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Proportional Hazards Models , Prospective Studies , Recurrence , Risk Assessment , Secondary Prevention/methods , Severity of Illness Index , Sweden , Treatment Outcome , Young AdultABSTRACT
Many members of the forkhead genes family of transcription factors have been implicated as important regulators of metabolism, in particular, glucose homeostasis, e.g., Foxo1, Foxa3, and Foxc2. The purpose of this study was to exploit the possibility that yet unknown members of this gene family play a role in regulating glucose tolerance in adipocytes. We identified Foxf2 in a screen for adipose-expressed forkhead genes. In vivo overexpression of Foxf2 in an adipose tissue-restricted fashion demonstrated that such mice display a significantly induced insulin secretion in response to an intravenous glucose load compared with wild-type littermates. In response to increased Foxf2 expression, insulin receptor substrate 1 (IRS1) mRNA and protein levels are significantly downregulated in adipocytes; however, the ratio of serine vs. tyrosine phosphorylation of IRS1 seems to remain unaffected. Furthermore, adipocytes overexpressing Foxf2 have a significantly lower insulin-mediated glucose uptake compared with wild-type adipocytes. These findings argue that Foxf2 is a previously unrecognized regulator of cellular and systemic whole body glucose tolerance, at least in part, due to lower levels of IRS1. Foxf2 and its downstream target genes can provide new insights with regard to identification of novel therapeutic targets.
Subject(s)
Adipose Tissue/metabolism , Forkhead Transcription Factors/metabolism , Glucose/metabolism , Insulin Receptor Substrate Proteins/metabolism , 3T3 Cells , Adipocytes , Animals , Down-Regulation , Gene Expression , Homeostasis/genetics , Humans , Mice , Mice, Inbred C57BLABSTRACT
We have developed a generic model for in vitro high-throughput screening for agents regulating transcription of genes in the mouse genome here exemplified by Foxc2, a forkhead transcription factor involved in regulation of adipocyte metabolism. We made a Foxc2-LacZ reporter "knock-in" mouse in which one of the two Foxc2 alleles has been inactivated and replaced by a LacZ reporter gene. Mouse embryonic fibroblasts, derived from such mice, were differentiated in vitro to adipocytes and used in cell-based screens. Forskolin as well as 12-O-tetradecanoylphorbol-13-acetate (TPA) increased levels of Foxc2nLacZ fusion protein. We could also demonstrate that this was paralleled by an increase in Foxc2 mRNA, transcribed from the wild type allele. This generic method offers a novel way of identifying both positive and negative upstream regulators of a gene, using high-throughput screening methodology. In a cell-based screen using such methodology we demonstrate efficacy by identifying NKH477 as a Foxc2 activating compound.
Subject(s)
Adipocytes/cytology , Cell Differentiation/drug effects , Drug Evaluation, Preclinical , Forkhead Transcription Factors/genetics , Small Molecule Libraries , Adipocytes/metabolism , Animals , Cells, Cultured , Embryo, Mammalian/cytology , Female , Fibroblasts/cytology , Fibroblasts/metabolism , Gene Knock-In Techniques , Lac Operon , Male , MiceABSTRACT
Thyroid dysgenesis encountered in 85% of patients with congenital hypothyroidism is a morphologically heterogeneous condition with primarily unknown pathogenesis. Here we identify sonic hedgehog (Shh) as a novel regulator of thyroid development. In Shh knockout mice the thyroid primordium is correctly specified in the pharyngeal endoderm, but budding and dislocation are slightly delayed. In late development the thyroid fails to form a bilobed gland. Instead a single thyroid mass is found unilaterally and mostly to the left of the midline. Thyroid-specific transcription factors (TTF-1 and TTF-2) and thyroglobulin are expressed indicating terminal differentiation. Strikingly, TTF-1- and TTF-2-positive cells aberrantly develop in the presumptive trachea of Shh-/- embryos. The ectopic tissue buds ventrolaterally into the adjacent mesenchyme, and less extensively into the tracheal lumen, forming follicle-like structures that accumulate thyroglobulin. Shh mRNA is not expressed in the thyroid precursor cells at any developmental stage. The results indicate that Shh signaling indirectly governs the symmetric bilobation of the thyroid during late organogenesis. Shh also seems to repress inappropriate thyroid differentiation in nonthyroid embryonic tissues. This study provides clues to the molecular mechanisms that might be dysregulated in thyroid hemiagenesis and development of ectopic thyroid tissue outside the thyroglossal duct.
Subject(s)
Gene Deletion , Thyroid Gland/metabolism , Trans-Activators/metabolism , Animals , Cell Differentiation , Epithelium/pathology , Hedgehog Proteins , Immunohistochemistry , In Situ Hybridization , Mice , Mice, Transgenic , RNA, Messenger/metabolism , Signal Transduction , Thyroglobulin/metabolism , Thyroid Gland/pathology , Time Factors , Trachea/pathologyABSTRACT
Enhancement of tumor cell growth and invasiveness by transforming growth factor-beta (TGF-beta) requires constitutive activation of the ras/MAPK pathway. Here we have investigated how MEK activation by epidermal growth factor (EGF) influences the response of fully differentiated and growth-arrested pig thyroid epithelial cells in primary culture to TGF-beta1. The epithelial tightness was maintained after single stimulation with EGF or TGF-beta1 (both 10 ng/ml) for 48 hours. In contrast, co-stimulation abolished the transepithelial resistance and increased the paracellular flux of [(3)H]inulin within 24 hours. Reduced levels of the tight junction proteins claudin-1 and occludin accompanied the loss of barrier function. N-cadherin, expressed only in few cells of untreated or single-stimulated cultures, was at the same time increased 30-fold and co-localised with E-cadherin at adherens junctions in all cells. After 48 hours of co-stimulation, both E- and N-cadherin were downregulated and the cells attained a fibroblast-like morphology and formed multilayers. TGF-beta1 only partially inhibited EGF-induced Erk phosphorylation. The MEK inhibitor U0126 prevented residual Erk phosphorylation and abrogated the synergistic responses to TGF-beta1 and EGF. The observations indicate that concomitant growth factor-induced MEK activation is necessary for TGF-beta1 to convert normal thyroid epithelial cells to a mesenchymal phenotype.
