Uncontrolled oxidative stress contributes to the development of neurodegenerative disease. This project focuses on the synthesis and analysis of four new groups of molecules based on a pyridol- containing N-heterocyclic amine parent molecule previously and successfully developed by the PI. The investigators demonstrated that this parent small molecule exhibits significant antioxidant reactivity in biological assays, is capable of crossing the blood brain barrier, and reduces beta-amyloid plaques in animal models of neurodegenerative disease. The investigators will use a rational design strategy to create the libraries and as such expect the new molecules to exhibit enhanced antioxidant activity (C.2- C.3), metabolic stability (C.4), and blood brain barrier permeability (C.5) compared to the parent molecule. The results from our first past screen will be used for further structural changes and studies. The new molecules are expected to provide potent antioxidant activity through structural modifications to the parent molecule, including (1) addition of pyridol groups, (2) changes in the base ring structure to target a range of toxic metal ions, (3) fatty acids, and (4) chemical groups inspired by nature?s own antioxidant store. We will study the first 13 new, enhanced antioxidant molecules using assays designed to understand pathways of chemical reactivity and cell culture work to assess toxicity and to quantify the ability of each new molecule to protect cells from four different models of oxidative stress. Molecules showing potent antioxidant activity will then be screened for metabolic stability and blood brain barrier permeability. The results from these studies will be used to produce hybrids of Groups 1 -2 with Groups 3-4, which will undergo similar screens to find optimized lead compounds suitable for further in vivo studies. This approach will identify the path(s) of protection each strategy of antioxidant enhancement provides and identify lead molecules to be explored further and proceed to future work involving animal toxicology, clearance, and activity assessment. Altogether, a comparative approach that uses data from chemical assays and biological studies will allow the investigators to identify molecules and moieties that provide the characteristics needed to serve as a therapeutic for neurodegenerative disorders arising from oxidative stress. This proposal takes a unique approach to targeting neurodegenerative disease by using synthetic chemistry to combine different reactive building-blocks into small molecules designed to have activity through targeting molecular features of neurodegeneration in a manner that is greater than the sum of the individual parts.
This project will produce potentially therapeutic small molecules designed to target neurodegenerative disease. The molecules are expected to exhibit enhanced antioxidant activity and retain the blood brain barrier permeability compared to the parent molecule developed previously by the PI. As such, the molecules may prove to be the basis of lead compounds for the effective treatment for neurodegenerative diseases where oxidative stress plays a substantial role. The investigators will also determine the mechanisms of antioxidant activity, metabolic stability, and blood brain barrier permeability for the small molecules by using chemical synthesis, chemistry-based reactivity assays, and biological cell culture studies. Successful completion of the project will help identify the best strategies for improving therapeutics that target brain-based oxidative stress.
