Blood Microsampling to Monitor Metabolic Profiles During Physical Exercise

Abstract

Monitoring approaches and technical improvements are key factors to improve a sportsman’s health, training, and recovery after an injury. In this study, a targeted metabolomics approach using microsampling with hemaPEN® was developed to measure changes in blood concentrations of nine amino acids and four organic acids before, during, and after exercise. The aim of this research project was to investigate if a reliable monitoring of metabolite levels during sports activity can be achieved by collecting one drop of whole blood at different time points. A hemaPEN device is an easy-to-use and noninvasive microsampling technique designed to collect four accurate and precise blood volumes simultaneously (10.96 µl). Twenty healthy volunteers between 19 and 30 years of age were included in this study. Physical activity consisted in running as fast as possible 1,600 m after 400 m warm-up. One drop of blood was collected at five time points: before exercise, after 800-m running, after 1,600 m, and 30 min and 60 min after finishing the exercise. The influence of physical activity on metabolite levels was evaluated using two ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) methods. Analytical performance criteria such as metabolite stability, method precision, trueness, and accuracy were found to be satisfactory. Expected significant metabolic changes were identified for lactic acid, main TCA cycle intermediates, and some amino acids (e.g., creatinine, choline, and taurine). This preliminary study performed on a small cohort demonstrated a high interest of using microsampling for fluxomics analysis, not only to collect quickly and easily biological samples during sports events but also because it is much easier to store and to process the samples than classical plasma/serum samples obtained by venipuncture. The present results open new avenue for fluxomics analysis in the context of health care.

Advanced Microsamples: Current Applications and Considerations for Mass Spectrometry-Based Metabolic Phenotyping Pipelines

“…Here, there was reduced analyte concentrations witnessed in DBSs compared to whole blood [73]. Accurate and precise collection of samples collected from a single drop of blood with minimal influence by hematocrit are similarly demonstrated by the hemaPEN (Trajan; Melbourne, Victoria, Australia) [27,72,79]. This has been examined in the scope of analytical chemistry for caffeine and paraxanthine, where comparing hemaPEN (Trajan; Melbourne, Victoria, Austrtalia) concentrations and those in whole blood revealed 6.90% and 5.40% difference in mean concentrations, respectively [27].…”

“…However, concentration decreases were observed in 2-oxoglutaric acid (35.1%) and methionine (56.5%); and concentrations increased for creatine (17.6%), and taurine (15.7%) [72].…”

“…Advanced dried sample devices collect samples as a fluid and produce a dried sample either with a polymer tip (volumetric absorptive microsampling "VAMS" -Neoteryx; Torrance, California, United States) or carriers akin to DBS cards such as the hemaPEN (Trajan; Melbourne, Victoria, Australia), HemaXis DB10 (DBS System SA; Gland, Switzerland), Capitainer qDBS and B-Vanadate (Capitainer AB; Solna, Sweden), TASSO-M20 (HemoLink; Seattle, Washington, United States), and HemaSpot HD and HF (Spot on Sciences; San Francisco, California, United States) [27,28,36,[66][67][68][69][70][71][72][73]. These technologies improve upon standard DBS cards by providing accurate/volumetric aspiration and thus heamatocrit-independent sample collection over a wide range of microsample sizes (2.74 µL -30 µL).…”

“…In a study of 20 healthy participants, the hemaPEN (Trajan; Melbourne, Victoria, Australia) was used to collect blood samples for analysis of 13 metabolites influenced by exercise, at training intervals, including nine amino acids and four organic acids [72]. Nine metabolite concentrations had variation <15% upon storage at -20˚C for five months.…”

Sustained Endurance Training Leads to Metabolomic Adaptation

“…Therefore, an assay is used that comprises distinct metabolites of one or more metabolic pathways of interest. Due to their potential importance in the adaptation to endurance sports and general health significant amino acids, biogenic amines, acylcarnitines, lysophosphatidylcholines, phosphatidylcholines, sphingolipids, polyunsaturated fatty acids (PUFAs), oxylipins, and bile acids were targeted [ 9 , 10 ].…”