Project Summary/Abstract
Reactive sulfur species (RSS), including hydrogen sulfide (H2S), persulfides (RSSH), and
polysulfides (RSSnR, n>1), are endogenously expressed biomolecules that play an important role
in human health and disease. For example, the biological activity of the most prominent member
of this class of compounds, H2S, has been shown to include anticancer activity, neuroprotection,
vascular relaxation, hormonal regulation, and energy production. Given these effects, it comes as
no surprise that RSS supplementation is being explored with great interest in preclinical models
of human illnesses, including cancer, Parkinson’s and Alzheimer’s disease, cardiovascular-
related pathologies, and other age-related illnesses. However, due to their high reactivity and
short half-life, the effective delivery and detection of RSS is extremely challenging. Thus, RSS
have untapped potential when it comes to the diagnosis and treatment of disease. In a similar
fashion, reactive selenium species (RSeS), such as hydrogen selenide (H2Se) and
hydroselenosulfides (RSeSH and RSSeH), have begun to attract significant attention from the
chemical biology and medicinal chemistry communities due to their purported therapeutic
properties. However, the biological activity of these selenium congeners is not well documented
due to similar inadequacies when it comes to their delivery and detection. Therefore, the work
described in this proposal is significant as it seeks to overcome these barriers by implementing
new and innovative chemistry that will harness the reactivity of RSS and RSeS to help realize the
biomedical applicability of these molecules for both the development of novel therapeutics,
including small molecule donors (or RSS/RSeS releasing compounds) with improved properties
(organelle-targeting, pathology-selective activation, self-reporting features for monitoring donor
progress and trafficking, and novel co-drug designs for improved activity and/or chemoprotective
effects) and diagnostics (reaction-based fluorescent sensors and RSS/RSeS-triggered
theranostics). This contribution will be innovative as it is expected to open the door to new
approaches for therapeutic intervention involving both RSS and RSeS.