Research Summary
Dr. Neilson received his PhD at Purdue University, and his research focused on the fields of food science, nutrition and toxicology. His PhD work involved characterization of the digestion, absorption, and pharmacokinetic behavior of dietary phytochemicals, which are metabolized by the same xenobiotic detoxification pathways as drugs and have generally poor bioavailability. Dr. Neilson then studied the role of diet in colon cancer prevention through a T32 training fellowship at the University of Michigan Cancer Center. These two experiences sparked his interest in studying how xenobiotic phytochemicals could be used to target the gut for prevention and amelioration of chronic disease. Phytochemicals, particularly phenolics, are particularly suited for targeting the gut for several key reasons:
- Phenolic phytochemicals have generally poor systemic bioavailability due to the gut barrier and efficient xenobiotic metabolism and exertion. There is no barrier to exposure in the gut Therefore, the gut epithelium, lumen and microbiome are exposed to concentrations 3-5 orders of magnitude greater than the vasculature and/or peripheral tissues
- The gut microbiome contains significantly more cells, genes, and pathways than the human host. Thus, there are more potential therapeutic targets in the gut than in peripheral tissues
- Phenolic phytochemicals are known to alter the composition and function of the gut microbiome
- Phenolic phytochemicals are metabolized by various gut bacteria into hundreds (if not thousands) of bioavailable metabolites. These gut metabolites represent a key mechanism by which poorly-available dietary components may exert their activities in circulation and peripheral tissues without actually reaching those tissues in appreciable concentrations.
Based on these ideas, research in the Neilson lab focuses on the interactions between dietary phytochemicals and the gut. Dr. Neilson’s current research interests are as follows:
- Interaction of poorly-absorbed dietary phytochemicals with gut microbiota
- Bioactivities of gut microbial metabolites (trimethylamine, trimethylamine N-oxide, polyphenol metabolites, etc.)
- Dietary strategies for prevention of gut dysfunction, obesity, type-2 diabetes, and cardiovascular disease
- Digestion, bioavailability, and metabolism of dietary phytochemicals
- Development of rapid, sensitive analytical methods including UPLC, HPLC and mass spectrometry
From 2011-2018, he was an Assistant and then Associate Professor at Virginia Tech in Blacksburg, VA. Dr. Neilson joined NCSU in 2019. Dr. Neilson has funding from the U.S. Department of Agriculture (USDA) and the food industry as Principal Investigator, and is a Co-Investigator on multiple NIH, USDA and industry grants.
Relevance of Research to CGIBD Mission: Dr. Neilson’s research is focused on nutrition and chronic diseases with significant gastrointestinal involvement, such as leaky gut, gut dysbiosis, gut inflammation, obesity and type-2 diabetes. Specifically, a major portion of his research program involves digestion, absorption, microbial metabolism and biological activities of dietary phytochemicals in the gut. Thus, his work thus dovetails with the CGIBD mission of performing multidisciplinary research to reduce the burden of gastrointestinal diseases.
CGIBD Focus Area(s): Microbiome