Formation of Cyclobutane Pyrimidine Dimers after UVA Exposure (Dark-CPDs) Is Inhibited by an Hydrophilic Extract of Polypodium leucotomos

Exposure to sun and especially to ultraviolet radiation (UVR) exerts well known detrimental effects on skin which are implicated in malignancy. UVR induces production of cyclobutane pyrimidine dimers (CPDs), immediately during exposure and even hours after the exposure, these latter being called dark-CPDs, as consequence of the effects of different reactive species that are formed. Fernblock® (FB), an aqueous extract of Polypodium leucotomos, has proven to have photoprotective and antioxidant effects on skin. The aim of our work was to investigate the potential photoprotective effect of FB against dark-CPD formation. Murine melanocytes (B16-F10) were exposed to UVA radiation and the production of dark-CPDs and different reactive oxygen and nitrogen species (ROS and RNS) was measured. Significant dark-CPD formation could be seen at 3h after UVA irradiation, which was inhibited by the pre-treatment of cells with FB. Formation of nitric oxide, superoxide and peroxynitrite was increased after irradiation, consistent with the increased CPD formation. FB successfully reduced the production of these reactive species. Hence, these results show how dark-CPDs are formed in UVA irradiated melanocytes, and that FB acts as a potential antioxidant and ROS scavenger, preventing the DNA damage induced by sun exposure.

Revisão de terapias no aumento de resposta da atividade melanocítica para repigmentação cutânea de portadores com vitiligo

O vitiligo é uma doença imunológica caracterizada pela despigmentação da pele, causando manchas acrômicas, sem predileção por sexo ou etnia. Ademais, pode provocar alterações emocionais, comprometimento da autoestima e nas relações sociais do indivíduo. Assim, esse trabalho propõe uma revisão sistemática da literatura objetivando evidenciar a eficiência de protocolos de terapias disponíveis para o vitiligo e sua correlação. Metodologia: Trata-se de um estudo de revisão sistemática, de caráter descritivo, retrospectivo realizado a partir de pesquisas nas principais bases de dados acadêmicas. Ex. PubMed, Lilacs e Periódicos Capes, etc. Assim, fez-se buscas livres de palavras relacionadas ao tema proposto: tratamento do vitiligo e associações, excluindo os trabalhos que mostraram ineficiência (baixo percentual de repigmentação) quando comparada aos tratamentos convencionais. Nesse sentido, foram encontrados 35 artigos científicos e 27 terapias distintas para o tratamento de vitiligo. Resultados e Discussão: Tais terapias foram divididas em 4 categorias: corticosteroides, fotobiomodulação, imunossupressores e antioxidantes. O uso de corticosteroides mostrou-se eficaz na estabilização da doença. Das fototerapias, a kelina agiu em 70% dos casos de repigmentação. Já os imunossupressores JAK demonstram repigmentação total ou acima de 75%. E os antioxidantes mostraram eficácia de 67% de repigmentação, com destaque para a espécie Polypodium leucotomos e Brosimum gaudichaudii com alto índice de repigmentação completa, principalmente quando associado a radiação UVB. Já o tratamento com Ginko biloba teve 80% de estabilização da doença. Conclusão: Os protocolos mostraram que a associação das fototerapias com terapias convencionais e inovadoras são mais frequentemente eficazes no tratamento do vitiligo, potencializando os resultados.

Diet in Dermatology: Review of Diet’s Influence on the Conditions of Rosacea, Hidradenitis Suppurativa, Herpes Labialis, and Vitiligo

The influence of dietary patterns on cutaneous disease has been an oft-posed question to dermatologists by patients in a clinical setting. Similarly, the popularity of nutritional supplementation with vitamins, minerals, and nutraceutical blends has been increasing. Dermatologists, primary care physicians, and other providers should be familiar with dietary interventions that are evidence-based and those that are more marketable than efficacious. In this review, the modification of diet, including dietary exclusion and dietary supplementation for the treatment of rosacea, hidradenitis suppurativa (HS), herpes labialis, and vitiligo was investigated. Despite abundant anecdotal evidence, the literature search found no high-quality evidence that an elimination diet for rosacea “trigger foods” improved rosacea symptoms though these elimination diets (of hot, spicy, alcohol-containing, or cinnamaldehyde-containing foods) had low risk of harm. There is evidence that zinc supplementation and vitamin D supplementation in deficient patients is helpful for treating HS. For herpes labialis, L-lysine supplementation was found to be effective for prophylaxis but not for decreasing duration of active lesions. For vitiligo, the use of the herb Polypodium leucotomos in conjunction with phototherapy was found to increase repigmentation, as well as vitamin D supplementation in deficient patients.