Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.1.1.17 (ornithine decarboxylase)
 6,351 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vivo studies in rodents suggest that prostaglandins and/or leukotrienes are involved in the epidermal induction of ornithine decarboxylase (ODC). Recently, we have shown that, in human epidermis, prostaglandins are not involved in this process. Here we report the role of leukotrienes in epidermal ODC induction in human skin. Topical flufenamic acid (Dignodolin), vehicle, or nothing was applied under plastic occlusion to three sites on the backs of healthy volunteers. This was followed 1 h later by Sellotape stripping. After renewed application and occlusion for 8 h, biopsies were carried out for the estimation of ODC levels. There were no significant differences in the levels of ODC between the flufenamic acid treated and control sites. To confirm this finding, test sites were irradiated with 3 MED of UVB. This was immediately followed by the application of flufenamic acid, vehicle, or nothing to the three irradiated sites. After 8 h, biopsies were taken, and the levels of ODC were again similar in the flufenamic acid- and the vehicle-treated sites. The data indicate that, following Sellotape stripping or UVB irradiation, neither lipoxygenase not cyclooxygenase products contribute to the in vivo induction of ODC in human epidermis.
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PMID:The induction of ornithine decarboxylase in human epidermis is independent of lipoxygenase and cyclo-oxygenase pathways. 140 5

We studied the influence of magnetic fields (MFs) and simulated solar radiation (SSR) on ornithine decarboxylase (ODC) and polyamines in mouse epidermis. Chronic exposure to combined MF and SSR did not cause persistent effects on ODC activity or polyamines compared to the animals exposed only to UV, although the same MF treatment was previously found to accelerate skin tumor development. In an acute 24-h experiment, an elevation of putrescine and down-regulation of ODC activity was observed in the animals exposed to a 100-microT MF. No effect was seen 24 h after a single 2-MED (minimal erythemal dose) exposure to SSR. The results indicate that acute exposure to 50 Hz MF does exert distinctive biological effects on epidermal polyamine synthesis.
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PMID:Epidermal ornithine decarboxylase and polyamines in mice exposed to 50 Hz magnetic fields and UV radiation. 973 30

Our recent results suggest that 50 Hz magnetic fields (MF) enhance ultraviolet (UV)-induced tumorigenesis in mouse skin. The aim of the present experiment was to study suppression of apoptosis as a possible mechanism for MF effects on skin tumorigenesis. Another aim was to test the importance of a UV and MF exposure schedule, particularly the role of MF exposure prior to UV irradiation. Female mice were exposed to a UV dose of 2 human MED and to 100 microT MF of 50 Hz, using the following exposure schedules: group 1 sham MF 24 h, UV 1 h, sham MF 24 h; group 2 sham MF 24 h, UV 1 h, MF 24 h; group 3 MF 24 h, UV 1 h, MF 24 h. Lamps emitting simulated solar radiation (SSR) were used for UV irradiation. Skin samples were analysed for apoptosis, expression of the p53 gene, activity of the enzyme ornithine decarboxylase (ODC) and polyamine concentrations. A significantly (p = 0.017) lower number of apoptotic cells was measured in group 2 compared to group 1. A similar but not statistically significant (p = 0.064) decrease was also detected in group 3. No p53 expression was detected in any sample. The levels of ODC and putrescine did not differ significantly between the UV-only and UV and MF-exposed groups. Spermidine and spermine levels were significantly (p = 0.014 and 0.014, respectively) lower in group 3 than in group 1, but no decrease was observed in group 2. Our findings suggest that SSR induces p53-independent apoptosis in mouse skin and that the apoptotic response may be inhibited by exposure to MF. The exposure schedule did not alter the MF effect. The results do not support a causal role for polyamines in MF effects on apoptosis.
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PMID:p53-independent apoptosis in UV-irradiated mouse skin: possible inhibition by 50 Hz magnetic fields. 1220 Oct 60