Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chronic exposure of human skin to solar irradiation results in a variety of preneoplastic and frankly neoplastic skin lesions. We have shown that in solar keratoses (SK) and in paralesional skin there is instead of an even distribution of succinic dehydrogenase (SDH) activity a relative decreased activity in the granular cell layer. Furthermore, there is enhancement of the usual concentration of glucose-6-phosphate dehydrogenase (G6PDH) activity in the granular zone as well as an increase in total G6PDH epidermal activity. In the experimental part of this study, six normal volunteer subjects had areas of normally non exposed skin (buttocks) irradiated with a 2 Mean erythema dose of ultra violet light (290--400 nm) on between 3 and 5 occasions per week for 2--6 week periods. The results obtained indicated that the same changes in enzyme activity localization take place in artificially irradiated normally non exposed epidermis as seen in normally exposed skin nearby actinic keratoses. It is suggested that these quantitative changes may be the basis of a model for the study of chronic ultra violet light damage to the epidermis.
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PMID:Quantitative changes in respiratory enzyme activity in premalignant lesions and experimentally irradiated skin. 71 87

We have demonstrated previously that following UVB irradiation to normal volunteers there is an increase in epidermal and stratum corneum thickness and an increase in the thymidine autoradiographic labeling index. These changes are coupled with alterations in epidermal glucose-6-phosphate dehydrogenase and succinic dehydrogenase activities, despite the absence of erythema clinically. The use of a sunscreen did not completely prevent these changes. In this study, we have examined the effects of repeated irradiation of human skin with either UVB or UVA alone in order to compare the changes produced in the epidermis and to ascertain whether UVA irradiation could cause these. Irradiation with either UVB or UVA alone was found to increase the mean epidermal thickness, the mean stratum corneum thickness, and mean keratinocyte height significantly. Glucose-6-phosphate dehydrogenase activity was significantly increased throughout the epidermis, and succinic dehydrogenase activity was significantly decreased. The autoradiographic labeling index was significantly increased following UVB irradiation but not following UVA irradiation. These results demonstrate that UVA alone can have a direct effect on epidermal morphology and metabolism, suggesting that protection of skin from UV radiation should include adequate protection from UVA.
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PMID:Epidermal changes in human skin following irradiation with either UVB or UVA. 379 92

After UV irradiation of human skin there is an increase in epidermal and stratum corneum thickness and an increase in the thymidine autoradiographic labeling index. Previously we have demonstrated that persistent exposure to ultraviolet radiation (UVR) alters the distribution and activities of glucose-6-phosphate dehydrogenase (G-6-PDH) and succinic dehydrogenase (SDH) within the epidermis; G-6-PDH activity is increased over the whole epidermis and SDH activity is diminished in the granular cell area but increased in the basal layer. When skin is protected by an efficient sunscreen and irradiated with UVB, there is almost complete inhibition of the erythema normally seen following UVR exposure. In this study we have investigated the cytochemical, cell kinetic, and histometric changes that take place in the epidermis after UVB irradiation, with and without two different types of sunscreen. Some of the histometric and metabolic changes associated with UVB exposure were still evident despite sunscreen protection and the successful blocking of the erythema response. The implications of these findings are discussed together with the use of sunscreens to prevent development of solar damage.
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PMID:Response of human skin to ultraviolet radiation: dissociation of erythema and metabolic changes following sunscreen protection. 682 29