Comparative analysis of obesity-related cardiometabolic and renal biomarkers in human plasma and serum

Authors: RAJAN, MEENU - University Of Gothenburg; SOTAK, MATUS - University Of Gothenburg; BARRENAS, FREDRIK - Uppsala University; SHEN, TONG - University Of California, Davis; BORKOWSKI, KAMIL - University Of California, Davis; ASHTON, NICK - University Of Gothenburg; BIORSERUD, CHRISTINA - University Of Gothenburg; LINDAHL, THOMAS - Linkoping University; RAMSTROM, SOFIA - Örebro University; SCHOLL, MICHAEL - University College London; LINDAHL, PER - University Of Gothenburg; FIEHN, OLIVER - University Of California, Davis; Newman, John; PERKINS, ROSIE - University Of Gothenburg; WALLENIUS, VILLE - University Of Gothenburg; LANGE, STEPHAN - San Diego State University; BORGESON, EMMA - University Of Gothenburg

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/2/2019
Publication Date: 10/28/2019
Citation: Rajan, M., Sotak, M., Barrenas, F., Shen, T., Borkowski, K., Ashton, N., Biorserud, C., Lindahl, T.L., Ramstrom, S., Scholl, M., Lindahl, P., Fiehn, O., Newman, J.W., Perkins, R., Wallenius, V., Lange, S., Borgeson, E. 2019. Comparative analysis of obesity-related cardiometabolic and renal biomarkers in human plasma and serum. Scientific Reports. 9. https://doi.org/10.1038/s41598-019-51673-0.
DOI: https://doi.org/10.1038/s41598-019-51673-0

Interpretive Summary: The measurement of biological markers associated with obesity-related cardiometabolic and kidney diseases may aid in the early detection of these conditions, allowing improved prevention and treatment strategies, both reducing the burdens of disease on society and enhancing individual quality of life. Efforts to identify such biomarkers are ongoing, and compounds appearing in the blood are desirable, as they could be easily adapted to current clinical practices. Clinical analyses are commonly performed on two different liquid compartments of blood, the plasma which is the liquid portion with all cellular components removed, and the serum, which is the liquid component left after the blood is allowed to clot. However, it is not clear whether such markers detected in plasma or serum can be used interchangeably. Here we used high-throughput screening to analyze 358 proteins and 76 lipids, selected because of their relevance to obesity-associated diseases, in plasma and serum from age- and sex-matched lean and obese humans. For the majority of proteins and lipids, the concentrations in plasma and serum correlated, but several proteins showed poor correlations, including PCSK9, a protein that helps regulate the amount of cholesterol in the bloodstream. Although most of the biomarkers had similar concentrations in plasma and serum, a subset of markers normally stored inside cells and proteins related to coagulation were either up- or down-regulated in the respective biofluids. Furthermore, for a small number of biomarkers (e.g., plasminogen activator inhibitor and monocyte-chemotactic protein-3), a difference in concentration between the obese and lean groups was only observed in either plasma or serum. Thus, our results indicate that the use of plasma or serum may yield different results when screening for obesity-related biomarkers, and both may be need to gain a complete picture.

Technical Abstract: The search for biomarkers associated with obesity-related cardiometabolic and kidney diseases is ongoing, but it is not clear whether plasma or serum can be used interchangeably to identify proteins and lipids of interest. Here we used high-throughput screening to analyze 358 proteins and 76 lipids, selected because of their relevance to obesity-associated diseases, in plasma and serum from age- and sex-matched lean and obese humans. For the majority of proteins and lipids, their concentrations correlated between plasma and serum, but several proteins showed poor correlations, including PCSK9. Although most of the biomarkers had similar concentrations in plasma and serum, a subset of intracellular stored markers and proteins related to coagulation were either up- or down-regulated in respective biofluid. Furthermore, for a small number of biomarkers (e.g., PAI and MCP-3), a difference in concentration between the obese and lean groups was only observed in either plasma or serum. Thus, our results indicate that the use of plasma or serum may yield different results when screening for obesity-related biomarkers