Salutary effects of transdermal curcumin on multiple indices of health span in rodent models of normal aging and hypertension

Abstract

Geroscience has helped to usher in a new and exciting era of aging drug development and evaluation of novel and repurposed agents, as well as natural compounds purported to target one or more aging hallmarks. Among the latter, curcumin has long been pursued as a promising strategy but has failed to provide convincing evidence in human trials. Oral intake is the typical route of administration tested for the vast majority of gerotherapeutic candidates, including curcumin, but efficacy is dependent upon good oral bioavailability and pharmacokinetics. However, unlike FDA-approved oral medications, many natural compounds, such as curcumin, have poor oral bioavailability, which may explain their limited success in translation. To overcome these inherent limitations, we tested a novel solvent-based formulation of concentrated curcumin (VASCEPTOR®), developed for effective skin penetration and delivery of high amounts of bioactive curcuminoids directly to the circulation on aging and age-related conditions. We demonstrate that short-term topical treatment (7.5 mg per dose) with VASCEPTOR® twice per week can improve both vascular health in a rat model of hypertension, while a late-life intervention in aged mice improves multiple indices of health span, including improved exercise tolerance, motor coordination, diastolic function (p < 0.05), a reduction in frailty status (p < 0.05) and expression of some age-related markers in tissues, particular heart and kidney. Thus, these data suggest that the therapeutic potential of curcumin can potentially be dramatically enhanced by topical delivery and, along with other promising candidates, should be prioritized for further development, testing and deployment to potentially target some manifestations of aging in humans.