Prevention of UVB radiation-induced oxidative stress in mice by topical administration of Azadirachta indica(neem) extract

Neem tree (Azadirachta indica A. Juss. fam. Meliaceae) has been extensively employed to combat diverse pathologies. Moreover, it has been described that its leaf extract present anticarcinogenic action. Thus, the neem extract (NE) chemical and antioxidant properties was evaluated, and also, the capacity of two dermatological formulations incorporated with neem extract (F1 and F2) to avoid oxidative UVB-induced skin injury in hairless mice. NE constituents were investigated and free radical scavenging ability were determined by different methods in vitro. Skin from mice treated with F1 and F2 and submitted to UVB radiation were tested for different parameters of inflammation and oxidative injury. Results show that the NE polyphenol and flavonoid content were 135.30 and 37.12mg/g, respectively. High performance liquid chromatography (HPLC) results demonstrated the existence of azarachtin, rutin, ursolic acid and tannic acid. NE presented scavenging ability by ABTS radical, ferric-reducing antioxidant power (FRAP), inhibition of lipid peroxidation and iron chelation. In vivo, it was observed that mice treated with F1 and F2 showed amelioration of the inflammation by reducing UVB induced skin edema. However, only samples from animals treated with F1 had lower neutrophil recruitment (measured by myeloperoxidase activity), and returning the oxidative status to baseline levels in parameters such as reduced glutathione level, ferric reducing ability (FRAP), and scavenging of free radical (ABTS). Concluding, NE demonstrated a good antioxidant property in vitro, and the data suggest the use of NE added F1 to prevent skin damage caused by UVB irradiation.(AU)

Big endotelina-1 e óxido nítrico em pacientes idosos hipertensos com e sem síndrome da apneia-hipopneia obstrutiva do sono / Big endothelin-1 and nitric oxide in hypertensive elderly patients with and without obstructive sleep apnea-hypopnea syndrome

FUNDAMENTO: O papel do estresse oxidativo em pacientes idosos hipertensos com síndrome de apneia-hipopneia obstrutiva do sono (SAHOS) é desconhecido. Objetivo: O objetivo foi avaliar os níveis de Big Endotelina-1 (Big ET-1) e Óxido Nítrico (NO) em pacientes idosos hipertensos com e sem SAHOS moderada a grave. MÉTODOS: Os voluntários permaneceram internados durante 24 horas. Obtivemos os seguintes dados: índice de massa corporal (IMC), Monitorização Ambulatorial da Pressão Arterial (MAPA) - 24 horas, e medicação atual. Sangue arterial foi coletado às 7:00 h e às 19:00 h para determinar níveis plasmáticos de NO e Big ET-1. A oximetria de pulso foi realizada durante o sono. A correlação de Pearson, Spearman e análise de variância univariada foram utilizadas para a análise estatística. RESULTADOS: Foram estudados 25 sujeitos com SAHOS (grupo 1) e 12 sem SAHOS (grupo 2), com idades de 67,0 ± 6,5 anos, 67,8 ± 6,8 anos, respectivamente. Não foram observadas diferenças significativas entre os grupos em IMC; no número de horas de sono; PA diastólica e sistólica em 24 h; PA de vigília; PA no sono; ou medicamentos usados para controlar a PA. Não foram detectadas diferenças nos níveis de NO e Big ET-1 plasmáticos às 19:00 h, mas às 7:00 h os níveis de de Big ET-1 foram mais altos (p = 0,03). No grupo 1, correlação negativa também foi observada entre a saturação de oxihemoglobina arterial média e a PA sistólica - 24 horas (p = 0,03, r = -0,44), e Big ET-1 (p = 0,04, r = 0,41). CONCLUSÕES: Na comparação entre idosos hipertensos com e sem SAHOS com PA e IMC semelhantes, observou-se níveis mais elevados de Big ET-1 após o sono no grupo SAHOS. Os níveis de NO não diferiram entre os pacientes hipertensos com ou sem SAHOS.

BACKGROUND: The role of oxidative stress in hypertensive elderly patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) is unknown. OBJECTIVE: The purpose was to evaluate the levels of big endothelin-1 (Big ET-1) and nitric oxide (NO) in elderly hypertensive patients with and without moderate to severe OSAHS. METHODS: Volunteers were hospitalized for 24 h. We obtained the following data: body mass index (BMI); 24-ambulatory blood pressure monitoring; and current medication. Arterial blood was collected at 7pm and 7am for determining plasma NO and Big ET-1 levels. Pulse oximetry was performed during sleep. Pearson's or Spearman's correlation and univariate analysis of variance were used for statistical analysis. RESULTS: We studied 25 subjects with OSAHS (group 1) and 12 without OSAHS (group 2) aged 67.0 ± 6.5 years and 67.8±6.8 years, respectively. No significant differences were observed between the groups in BMI; number of hours of sleep; 24-h systolic and diastolic BPs; awake BP, sleep BP and medications to control BP between groups. No differences were detected in plasma Big ET-1 and NO levels at 19:00 h, but plasma Big ET-1 levels at 7:00 h were higher in group 1 (p =0.03). In group 1, a negative correlation was also observed between the mean arterial oxyhemoglobin saturation level, 24-h systolic BP (p = 0.03, r = -0.44), and Big ET-1 (p = 0.04, r = -0.41). CONCLUSIONS: On comparing elderly hypertensive patients with and without OSAHS having similar BP and BMI, we observed higher Big ET-1 levels After sleep in the OSAHS group. NO levels did not differ between the hypertensive patients with or without OSAHS.