Natural antioxidants in hybrids for the treatment of neurodegenerative diseases: a successful strategy?

Taken together, multitarget (hybrid) compounds and other chemical compounds containing antioxidant moieties are prone to several disadvantages: metabolic instability, false-positive results in (some - nonsuitable) in vitro assays and unknown modes of action. There are also problems of transferring the relevance of in vitro data to an in vivo setup. Nevertheless, this does not mean that antioxidants are not versatile and promising components of hybrids, but only specific assays for assessing the compounds' activities are suitable. The methods deemed suitable have to be carefully selected on the basis of the chemical structure of the compounds under investigation. Positive results should not be overinterpreted. The often unknown modes of action of natural antioxidants with regard to neuroprotection in vitro and in vivo still hamper the development of effective hybrid molecules. © 2017 Future Science Ltd.