ABSTRACT
Abstract Prolonged overexposure to catecholamines causes toxicity, usually credited to continuous adrenoceptor stimulation, autoxidation, and the formation of reactive pro-oxidant species. Non-differentiated SH-SY5Y cells were used to study the possible contribution of oxidative stress in adrenaline (ADR)-induced neurotoxicity, as a model to predict the toxicity of this catecholamine to peripheral nerves. Cells were exposed to several concentrations of ADR (0.1, 0.25, 0.5 and 1mM) and two cytotoxicity assays [lactate dehydrogenase (LDH) release and 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) reduction] were performed at several time-points (24, 48, and 96h). The cytotoxicity of ADR was concentration- and time-dependent in both assays, since the lowest concentration tested (0.1mM) also caused significant cytotoxicity at 96h. N-acetyl-cysteine (1mM), a precursor of glutathione synthesis, prevented ADR-induced toxicity elicited by 0.5mM and 0.25mM ADR following a 96-h exposure, while the antioxidant Tiron (100µM) was non-protective. In conclusion, ADR led to mitochondrial distress and ultimately cell death in non-differentiated SH-SY5Y cells, possibly because of ADR oxidation products. The involvement of such processes in the catecholamine-induced peripheral neuropathy requires further analysis.
Subject(s)
Epinephrine/agonists , Peripheral Nervous System Diseases/classification , Toxicity , Neurons/classification , Peripheral Nerves/abnormalities , Bromides/antagonists & inhibitors , Oxidative Stress/drug effects , Antioxidants/pharmacologyABSTRACT
ABSTRACT Objective Dietary supplements use is increasing. Dietary supplements may contain high doses of substances or dangerous ingredient combinations. This article aims to investigate, by analyzing dietary supplements labels, if there are any doping substances or dangerous amounts of any other component in the reviewed dietary supplements. Methods Several brands which possessed their supplements sorted in pre-workout and post-workout were analyzed. 40 dietary supplements with all ingredients described were included. The minimum and maximum dosages of dietary supplements were statistically described as Mean±SD. Results Citrus aurantium extract, Yohimbe extract, Garcinia cambogia extract and Maca root extract were reported in some of the analyzed dietary supplements. Regarding caffeine, the pre-workout group displayed higher mean caffeine (241±86mg) than the post-workout group (183±68mg), and the minimal mean dose was 226±84mg; meanwhile, the maximal mean dose was 242±88mg. Concerning creatine, the pre-workout group displayed lower mean creatine (3106±1079mg) than the post-workout group (4137±4177mg), and the minimal mean dose was 3167±1728mg; meanwhile, the maximal mean dose was 3917±3643mg. The salt content in the post-workout group displayed a much higher mean (2155±4486mg) than the pre-workout group (464±605mg), and the minimal mean dose was 1635±3930mg; meanwhile, the maximal mean dose was 1708±3926g. Conclusions No doping substances were reported in the dietary supplements, but consumption recommendations on the label could lead to excessive consumption of some not yet fully tested ingredients.
RESUMO Objetivo O uso de suplementos alimentares está a aumentar. Estes podem conter altas doses de substâncias ou combinações de ingredientes perigosas. Este artigo procura encontrar, analisando os rótulos dos produtos, se existem substâncias dopantes ou nocivas. Métodos Foram analisadas várias marcas cujos respectivos suplementos foram classificados em pré e pós-treino. Foram incluídos 40 suplementos com todos os ingredientes descritos. A respectiva dose mínima e máxima foi descrita estatisticamente como média ± DP. Resultados Extratos de Citrus aurantium, Yohimbe, Garcinia cambogia e raiz de Maca foram encontrados nos suplementos analisados. O grupo pré-treino apresentou maior média de cafeína (241±86mg) do que o grupo pós-treino (183±68mg), e a dose média mínima foi de 226±84mg, enquanto a dose média máxima foi de 242±88 mg. O grupo pré-treino apresentou menor média de creatina (3106±1079mg) do que o grupo pós-treino (4137±4177mg), e a dose média mínima foi de 3167±1728mg, enquanto a dose média máxima foi de 3917±3643mg. O grupo pós-treino apresentou uma maior média de sal (2155±4486mg) do que o grupo pré-treino (464±605mg), e a dose média mínima foi 1635±3930mg, enquanto a dose média máxima foi de 1708±3926mg. Conclusão Não foram encontradas substâncias dopantes nos suplementos, mas algumas recomendações de consumo nos rótulos poderão levar à sobredose de certos ingredientes menos testados.