Bryan Hudson Hossy

Silymarin Reduces Profibrogenic Cytokines and Reverses Hepatic Fibrosis in Chronic Murine Schistosomiasis

ABSTRACT In chronic schistosomiasis, hepatic fibrosis is linked to the portal hypertension that causes morbidity in Schistosoma mansoni infection. Silymarin (SIL) is a hepatoprotective and antioxidant medicament largely prescribed against liver diseases that has previously been shown to prevent fibrosis during acute murine schistosomiasis. Here we employed silymarin to try to reverse established hepatic fibrosis in chronic schistosomiasis. Silymarin or vehicle was administered to BALB/c mice every 48 h, starting on the 40th (80 days of treatment), 70th (50 days), or 110th (10 days) day postinfection (dpi). All mice were sacrificed and analyzed at 120 dpi. Treatment with silymarin reduced liver weight and granuloma sizes, reduced the increase in alanine aminotransferase and aspartate aminotransferase levels, and reduced the established hepatic fibrosis (assessed by hydroxyproline contents and picrosirius staining). Treatment with silymarin also reduced the levels of interleukin-13 (IL-13) in serum and increased the gamma interferon (IFN-γ)/IL-13 ratio. There was a linear correlation between IL-13 levels in serum and hydroxyproline hepatic content in both infected untreated and SIL-treated mice, with decreased IL-13 levels corresponding to decreased hydroxyproline hepatic contents. Treatment with either SIL or N-acetylcysteine reduced both proliferation of fibroblast cell lines and basal/IL-13-induced production of collagen I, indicating that besides inhibiting IL-13 production during infection, SIL antioxidant properties most likely contribute to inhibition of collagen production downstream of IL-13. These results show that silymarin interferes with fibrogenic cytokines, reduces established fibrosis, and inhibits downstream effects of IL-13 on fibrogenesis, indicating the drug as a safe and cheap treatment to liver fibrotic disease in schistosomiasis.

Phototoxic assessment of a sunscreen formulation and its excipients: An in vivo and in vitro study

BACKGROUND Cosmetic preservatives are used to protect cosmetic formulations and improve its shelf-life. However, these substances may exert phototoxic effects when used under sunlight. OBJECTIVE To assess safety, efficacy and putative phototoxic effects of a sunscreen formulation SPF 30 and its excipients. MATERIALS/METHODS Irradiation was performed with solar simulated light (SSL) and the sunscreen from the School of Pharmacy/UFRJ/Brazil. We used albino hairless mice in different groups (control (G1), only irradiated (G2), sunscreen plus irradiation (G3) and vehicle plus irradiation (G4) for morphological assessment and immunefluorescence detection to OKL38. In vitro analyses were with a Saccharomyces cerevisiae (SC) strain plus SSL in the presence of methylparaben, propylparaben, imidazolidinyl urea, aminomethyl propanol and their association. RESULTS G3 and G4 displayed photosensitization leading to thickening of the epidermis and increased dermal cellularity. G4 displayed strong OKL38 labeling when compared with other groups. Aminomethyl propanol, methylparaben and propylparaben are endowed with phototoxic activity against SC. Propylparaben displayed the highest phototoxic effect, followed by excipients association. CONCLUSIONS The sunscreens vehicle is endowed with phototoxic activity. Propylparaben was the most phototoxic agent, increasing the overall phototoxicity of excipient association, pointing to a critical concern regarding vehicle associations intended to cosmetic purposes.

Copaiba oil enhances in vitro/in vivo cutaneous permeability and in vivo anti-inflammatory effect of celecoxib

The aim of this article was to use copaiba oil (C.O) to improve skin permeability and topical anti‐inflammatory activity of celecoxib (Cxb).

Histological observation of hairless mice skin after exposure to Simulated Solar Light: Comparison between the histological findings with different methodologies and 3R principle correlations

BACKGROUND Albino hairless mouse (AHM) has been used as a biological model in photodermatology. However, the experimental landscape is diverse to follow and need particular attention. PURPOSE Irradiation parameters were investigated for the development of a protocol to assess alterations in the AHM skin using Simulated Solar Light (SSL). The present study was compared with published articles (last 15 years) according to irradiation protocols, morphological findings to minimize animal suffering and UV exposure. MATERIALS AND METHODS Three groups: Control (G1), experimental - sunburn (G2) and skin photodamage assay (G3). G2 were immobilized and exposed to SSL once for 15, 30 and 45min. G3 were exposed to SSL, without immobilization, for 15min once a day for one week. The dorsal skin was analyzed using hematoxylin and eosin technique. RESULTS G2 displayed different sunburn degrees. Based on the profile of the observed morphological alterations, a 15min irradiation was chosen as the exposure time to expose G3, without immobilization, for 5 consecutive days. CONCLUSION These conditions produced the same morphological changes in the AHM with a shorter solar exposure time, without immobilizing the animals but using environmental exposure fluences, conforming to 3R (reduction - refinement - replacement) recommendations.

MONITORAMENTO DE TECNOLOGIAS DO CAFÉ: UM PANORÂMA PARA O MELHORAMENTO GENÉTICO

No ano de 2012 o cafe representou ao Brasil 2,0% do valor total de exportacoes. Este resultado positivo tem sido reflexo de um esforco acumulativo ao longo dos anos da comunidade cientifica em aperfeicoar atraves de tecnicas de melhoramento genetico tal planta sendo o principal alvo o combate ao stress abiotico em consonância as alteracoes climaticas. Assim sendo, sequencias do DNA da coffea arabica vem sendo mapeadas para producao de cafeeiros resistentes ao estresse abiotico sendo o gene CAHB12 um dos mais recentemente pesquisados e ineditamente esclarecidos para o melhoramento deste ao estresse hidrico e salino. Atraves da ferramenta de busca de patentes Derwent Innovations Index desenvolveu-se uma estrategia de mapeamento de tecnologias similares a exploracao do gene CAHB12 da coffea arabica. Observou-se a nao existencia desta tecnologia em tal especie, porem identificaram-se outras sequencias para o mesmo proposito. O principal pais depositante de patentes sobre melhoramento genetico do cafe e os EUA e a maior empresa depositante a BASF. Mapearam-se tambem os principais grupos de pesquisa em melhoramento genetico do cafe no Brasil.