TY  - JOUR
A1  - Kratz, Daniel
A1  - Thomas, Dominique Jeanette
A1  - Gurke, Robert
T1  - Endocannabinoids as potential biomarkers: it's all about pre-analytics
T2  - Journal of Mass Spectrometry and Advances in the Clinical Lab
N2  - Introduction: Arachidonoyl ethanolamide (AEA) and 2-arachidonoyl glycerol (2-AG) are central lipid mediators of the endocannabinoid system. They are highly relevant due to their involvement in a wide variety of inflammatory, metabolic or malign diseases. Further elucidation of their modes of action and use as biomarkers in an easily accessible matrix, like blood, is restricted by their susceptibility to deviations during blood sampling and physiological co-dependences, which results in high variability of reported concentrations in low ng/mL ranges.
Objectives: The objective of this review is the identification of critical parameters during the pre-analytical phase and proposal of minimum requirements for reliable determination of endocannabinoids (ECs) in blood samples.
Methods: Reported physiological processes influencing the EC concentrations were put into context with published pre-analytical research and stability data from bioanalytical method validation.
Results: The cause for variability in EC concentrations is versatile. In part, they are caused by inter-individual factors like sex, metabolic status and/or diurnal changes. Nevertheless, enzymatic activity in freshly drawn blood samples is the main reason for changing concentrations of AEA and 2-AG, besides additional non-enzymatic isomerization of the latter.
Conclusion: Blood samples for EC analyses require immediate processing at low temperatures (>0 °C) to maintain sample integrity. Standardization of the respective blood tube or anti-coagulant, sampling time point, applied centrifugal force and complete processing time can further decrease variability caused by sample handling. Nevertheless, extensive characterization of study participants is needed to reduce distortion of clinical data caused by co-variables and facilitate research on the endocannabinoid system.
KW  - Endocannabinoid
KW  - Pre-analytics
KW  - Blood sampling
KW  - Anandamide
KW  - 2-Arachidonoyl glycerol
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/77943
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-779432
SN  - 2667-145X
VL  - 22
SP  - 56
EP  - 63
PB  - Elsevier
CY  - Amsterdam
ER  -