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The Mascarene Aloes are used in the traditional pharmacopoeia against various ailments including cutaneous diseases and as antispasmodics. Scientific evidence to support these claims is non-existent and mainly based on the scientific repute of A. vera. The antioxidant profile of methanolic leaf extracts of A. purpurea Lam., A. tormentorii (Marais) L. E. Newton & G. D. Rowley, A. lomatophylloides Balf. f., A. macra Haw. and A. vera (L.) Burm. f. was studied using the total antioxidant capacity, copper equivalent and superoxide dismutase assays. In vitro cytotoxicity was evaluated on CAD (Cath.-a-differentiated) neuronal cells by the methyl tetrazolium assay, and the neuroprotective profile was assessed using hydrogen peroxide-induced neurotoxicity with the CAD cells. The aloin and vitexin content were determined by high-performance liquid chromatography with diode-array detection. A. purpurea had the highest aloin content (546.6 nmol/g), while A. tormentorii had the highest vitexin content (67.3 nmol/g). A. macra (concentration <0.1 mg/mL) elicited a 10% cytotoxicity effect on CAD cells while other Mascarene Aloes were not cytotoxic. This study validates the antioxidant and neuroprotective potential of Mascarene Aloes focusing on their aloin and vitexin content that are also present in other reputed medicinal Aloes., (Copyright © 2017 John Wiley & Sons, Ltd.)

Withania somnifera L. Dunal (Solanaceae), also known as 'ashwagandha' in Sanskrit and as 'Indian ginseng', is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer, with antiaging, antistress, immunomodulatory and antioxidant properties. There is a paucity of data on the potential neuroprotective effects of W. somnifera root, as traditionally used, against H(2)O(2)- and Aβ((1-42))-induced cytotoxicity which are current targets for novel approaches to treat dementia, especially dementia of the Alzheimer's type (AD). In this study, an aqueous extract prepared from the dried roots of W. somnifera was assessed for potential protective effects against H(2)O(2)- and Aβ((1-42))-aggregated fibril cytotoxicity by an MTT assay using a differentiated rat pheochromocytoma PC12 cell line. The results suggest that pretreatments of differentiated PC12 cells with aqueous extracts of W. somnifera root significantly protect differentiated PC12 cells against both H(2)O(2)- and Aβ((1-42))-induced cytotoxicity, in a concentration dependent manner. To investigate the compounds that could explain the observed effects, the W. somnifera extract was analysed by liquid chromatography-serial mass spectrometry and numerous withanolide derivatives, including withaferin A, were detected. These results demonstrate the neuroprotective properties of an aqueous extract of W. somnifera root and may provide some explanation for the putative ethnopharmacological uses of W. somnifera for cognitive and other neurodegenerative disorders that are associated with oxidative stress., (Copyright © 2010 John Wiley & Sons, Ltd.)