Research

Keywords

Mass spectrometry, biomarkers, analytical, bioanalytical, tobacco, diabetes, obesity, assays, method development, chromatography, analysis

Summary 

The focus of Dr. Lorkiewicz's research is to utilize mass spectrometry-based methodology in applications that help advance discovery in the fields of environmental, toxicological and basic biological research.

Research Interests

Development and implementation of workflows for Stable Isotope Resolved Metabolomics (SIRM)

SIRM technology allows for effective pathway tracing and elucidation by following the fate of isotopically labeled metabolites. The major bottleneck of this methodology is data reduction and analysis, as the mass spectral datasets consist of thousands of isotopologue peaks. Dr. Lorkiewicz's work has focused on developing appropriate frameworks to analyze, visualize and interpret SIRM data. He standardized methodology for examining glucose metabolism in cells and tissues using [13C6]-glucose and [15N2,13C]-glutamine. This data analysis methodology has been applied to studying major metabolic pathways in lung and breast cancer cells and recently in cardiac progenitor cells. Current work focuses on developing SIRM analysis frameworks to study [13C6]-glucose in-vivo, in mouse models.

Instrumental analysis and measurement of biomarkers of tobacco exposure

Dr. Lorkiewicz received funding for two pilot project human studies which measured the extent of exposure and/or levels of volatile organic compounds (VOCs) and tobacco alkaloids (TAs) in the urine and their removal over 3 hours after exposure to different tobacco products. Further, for the purpose of these AHA Tobacco Regulation and Addiction Center (ATRAC) he established robust, high-throughput liquid chromatography mass spectrometric (LC-MS) methods for detection and quantification of urinary metabolites of VOCs and TAs, as well as free biogenic monoamines and their metabolites in urine. These assays provided ATRAC with capacity to measure exposures to harmful and potentially harmful chemicals found in tobacco products and their systemic effects. Dr. Lorkiewicz's research efforts resulted in 7 publications and helped inform the design of the human tobacco study – CITU 2.0. development of a robust UHPLC-MS/MS assay - for analysis of 28 urinary metabolites of volatile organic compounds and 5 tobacco alkaloids. Current work focuses on developing additional LC-MS assays for measuring stress hormones and discovery of novel biomarkers of exposure to new and emerging tobacco products.

Lab Members

Zhengzhi Xie, PhD, David Hoetker, Tatiana Krivokhizhina PhD, Pawel Lorkiewicz PhD

Positions and Education

Dr. Lorkiewicz received his Ph.D. in 2009 in Analytical Chemistry from the University of Louisville and completed his post-doctoral training at the Center for Regulatory and Environmental Analytical Metabolomics at the University of Louisville. He pursued his scientific career as a research scientist at the Diabetes and Obesity Center, and later as Faculty in the Christina Lee Brown Envirome Institute.

Dr. Lorkiewicz has over 13 years of extensive hands-on experience in mass spectrometric detection and bioanalysis of small molecules, metabolites and xenobiotics. His expertise includes MS based targeted and untargeted metabolomics, lipidomics, biomarker discovery and method development using a multitude of mass spectrometry-based platforms, including high resolution, high accuracy FT-ICR MS, 2D-LC-MS Orbitrap, GCxGC-TOF MS, MALDI-TOFMS for unbiased analyses and global screening, as well as UHPLC-MS/MS, GC-MS platforms for targeted analyses. He has developed and implemented workflows for Stable Isotope Resolved Metabolomics (SIRM) from experiment design, execution to MS data collection, analysis and interpretation. In addition to the untargeted metabolomics and lipidomics workflows and development of the SIRM HRAM MS platform, Dr. Lorkiewicz has developed expertise in targeted workflows utilizing triple quadrupole-based MS systems with UHPLC/UPLC front-end and GC-MS to characterize and quantify small molecular weight compounds including metabolites and reactive nucleophile adducts such as mercapturates, and carnosine adducts. In the past 6 years Dr. Lorkiewicz has served in co-directorship and management roles of two mass spectrometry core laboratories at the University of Louisville – the Bioanalytics Core at the Diabetes and Obesity Center and the CREAM mass spectrometry facility.

Positions

Assistant Professor of Chemistry, Department of Chemistry and Division of Environmental Medicine 

Investigator, Christina Lee Brown Envirome Institute, University of Louisville School of Medicine

Technical Director, Mass Spectrometry and Bioanalytical Core, Diabetes and Obesity Research Center

Education

Postdoctoral Associate 2009-2013 Post-doctoral Fellowship in Stable Isotope Resolved Metabolomics,Dept. of Chemistry, University of Louisville, Louisville, KY

Ph.D. in Analytical Chemistry 2009, University of Louisville, Louisville, KY

M.S. in Pharmacy 2002, Medical University of Lublin, Lublin, Poland

Speaking & Events

April 10, 2019: E-Cigarette Interview on the "UofL Today with Mark Hebert" Radio Show

Contact

Pawel Lorkiewicz

Department of Medicine

School of Medicine

pawel.lorkiewicz@louisville.edu

502-852-5750

421C, Baxter II

580 South Preston St.

Louisville KY 40202