Feeding behavior is critical for animal survival, and is also a fundamental aspect of energy homeostasis. This process is regulated by a highly complex neuroendocrine system which involves a multitude of neuropeptides and amines. Despite decades of work on individual neurotransmitter or peptidergic signaling systems, the general organizational principles underlying neuromodulation are still poorly understood. This is, in part, due to a lack of analytical capabilities to measure and identify these low abundance endogenous signaling molecules in a complex microenvironment. The long term goal of our research is to develop new bioanalytical methods to elucidate the complex identities and functional roles of neuropeptides in food intake and to expand our fundamental understanding of cotransmission and neuromodulation at the molecular level. During our previous grant funding period, considerable progress has been made leading to the discovery of more than 200 novel neuropeptides with several neuropeptide families consisting of as many as 20-40 members in a simple crustacean model system. This stunning chemical complexity coupled with its best characterized neuronal circuit offers an unprecedented opportunity to investigate the intriguing question whether these individual variants play distinct roles in regulation of food intake. To address significant biological questions related to functional significance of peptide multiplicity and diversity, we propose the development and application of new analytical methodologies and capabilities using both the crustacean and mammalian nervous systems.
The specific aims of the proposal include: (1) To develop a MALDI-based mass spectral imaging (MSI) technique for mapping co-localization patterns of individual isoforms of extended peptide families and amine neurotransmitters in identified neurons and the feeding circuits. A set of novel multiplexed isobaric labeling reagents will be incorporated for quantitative assessment of neuropeptide expression upon feeding;(2) To develop a nanoparticle-based affinity-enhanced microdialysis in vivo sampling technique coupled with monolithic microscale separation for MS detection and quantitation of secreted neuropeptides in response to food intake;(3) To determine the functional consequences of neuropeptide isoforms via a combination of mass spectrometric and electrophysiological techniques. Individual variants of major peptide families involved in food intake will be investigated for their differential degradation profiles and distinct physiological actions on the feeding circuits. The outcome of the proposed research will be the development of innovative methodologies for probing neurochemistry at the cellular and network levels and an improved understanding of peptide multiplicity in regulation of food intake and other physiological functions. The parallel application of these new methods to both crustacean and mammalian nervous systems in feeding will accelerate our pace towards the development of new therapeutics for feeding disorders.

Public Health Relevance

The growing incidence of eating disorders and their associated health costs have led to intensive research efforts directed at understanding the mechanisms and signaling pathways that control and regulate food intake. This grant application aims at developing mass spectrometry-based strategies to characterize neuropeptides involved in feeding. The molecular insights gained from this research promise to increase our knowledge about peptidergic signaling and neuromodulation in the regulation of this essential physiological process, which could ultimately lead to the development of new therapeutic strategies for feeding disorders that have become a big concern of modern societies.

National Institute of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Research Project (R01)
Project #
Application #
Study Section
Enabling Bioanalytical and Imaging Technologies Study Section (EBIT)
Program Officer
Sechi, Salvatore
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Wisconsin Madison
Schools of Pharmacy
United States
Zip Code
Jiang, Xiaoyue; Xiang, Feng; Jia, Chenxi et al. (2018) Relative Quantitation of Neuropeptides at Multiple Developmental Stages of the American Lobster Using N, N-Dimethyl Leucine Isobaric Tandem Mass Tags. ACS Chem Neurosci 9:2054-2063
Yang, Ning; Anapindi, Krishna D B; Rubakhin, Stanislav S et al. (2018) Neuropeptidomics of the Rat Habenular Nuclei. J Proteome Res 17:1463-1473
Cao, Qinjingwen; Ouyang, Chuanzi; Zhong, Xuefei et al. (2018) Profiling of small molecule metabolites and neurotransmitters in crustacean hemolymph and neuronal tissues using reversed-phase LC-MS/MS. Electrophoresis 39:1241-1248
DeLaney, Kellen; Sauer, Christopher S; Vu, Nhu Q et al. (2018) Recent Advances and New Perspectives in Capillary Electrophoresis-Mass Spectrometry for Single Cell ""Omics"". Molecules 24:
Frost, Dustin C; Rust, Clayton J; Robinson, RenĂ£ A S et al. (2018) Increased N,N-Dimethyl Leucine Isobaric Tag Multiplexing by a Combined Precursor Isotopic Labeling and Isobaric Tagging Approach. Anal Chem 90:10664-10669
DeLaney, Kellen; Buchberger, Amanda; Li, Lingjun (2018) Identification, Quantitation, and Imaging of the Crustacean Peptidome. Methods Mol Biol 1719:247-269
Chen, Bingming; Zhong, Xuefei; Feng, Yu et al. (2018) Targeted MultiNotch MS3 Approach for Relative Quantification of N-Glycans Using Multiplexed Carbonyl-Reactive Isobaric Tags. Anal Chem 90:1129-1135
Zhang, Yuzhuo; DeLaney, Kellen; Hui, Limei et al. (2018) A Multifaceted Mass Spectrometric Method to Probe Feeding Related Neuropeptide Changes in Callinectes sapidus and Carcinus maenas. J Am Soc Mass Spectrom 29:948-960
Chen, Zhengwei; Glover, Matthew S; Li, Lingjun (2018) Recent advances in ion mobility-mass spectrometry for improved structural characterization of glycans and glycoconjugates. Curr Opin Chem Biol 42:1-8
Bratburd, Jennifer R; Keller, Caitlin; Vivas, Eugenio et al. (2018) Gut Microbial and Metabolic Responses to Salmonella enterica Serovar Typhimurium and Candida albicans. MBio 9:

Showing the most recent 10 out of 124 publications