Exploration of SCFA in human multi-compartments using 3-nitrophenylhydrazine-LC-MS

International audienceShort-chain fatty acids (SCFAs) are metabolites involved in many physiological processes. A disruption of their metabolism is suspected in diseases of the digestive system (inflammatory diseases) but also in neurodegenerative diseases such as Alzheimer's disease. Currently, one of the reference methodologies for the quantitative analysis of SCFA is based on the use of GC-MS due to its sensitivity and reproducibility. However, its technical implementation is delicate, limiting in particular the throughput of the analyzes carried out. Our objective is to propose a method for absolute quantification of SCFA that is easier to implement and for future use in a clinical environment for a large number of types of biological samples (stool, urine, serum, saliva, CSF, and dried blood spot). With this objective we favored a chemical derivatization approach in order to promote the detection and analytical separation of these metabolites. The derivatizing agent we selected, 3-nitrophenylhydrazine (3NPH), meets these criteria. In addition, the use of this molecular pattern on a complex sample will promote the detection and identification of all metabolites carrying a carboxylic acid function beyond the SCFAs targeted in this sample. After methodological validation (robustness, repeatability, matrix effect, carryover, LLOQ), its use makes it possible to propose reference values of SCFA concentrations for each type of sample. This quantitative methodology also allows longitudinal monitoring of SCFA concentrations. In particular, in saliva, our results show a circadian evolution of SCFA concentrations. Validated on several types of samples, our approach makes it possible to quantify the metabolism of SCFAs at the level of an individual and longitudinally

3-NPH derivatization of SCFAs in human biofluids for longitudinal and multi-matrix exploration

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Implementation of Quantification in Exploratory Metabolomic Analyses

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Multi-Compartment SCFA Quantification in Human

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Metabolomic & lipidomic information contained in Dried Blood Spot (DBS) vs. serum

International audienceDBS (Dried Blood Spot) are used for the screening of neonatal diseases and monitoring adults suffering from certain diseases in clinical context. DBS is a self-sampling device which is less invasive and requires less sample than a blood test. They can be sent by mail to the hospital allowing everyone to get access easily to biological analysis even in remote area or for elderly patients with mobility problems. Their use in new contexts has been widespread: carrying out anti-doping tests, the research of biomarkers of galactosemia or detection of cancer. In this work, we propose to compare quantitative data and exploratory metabolomic data between DSB and serum. For quantitative data, we quantified 6 short-chain fatty acids (SCFA), 20 bile acids, 20 tryptophan intermediates and 8 organic acids from TCA cycle. Two trends emerge: the first one is that the majority of the serum information is found in DBS. The second one is that DBS brings complementary information not found in serum. Indeed, an overlay of the metabolic cards of serum and DBS highlights a wider metabolic coverage for DBS. These results make it possible to envisage the use of DBS in both quantitative and exploratory metabolomic analyses. However, building up a cohort can last several months or years, so it will be necessary to clearly define the impact of storage conditions (temperature, hygrometry and light exposure) as well as its lasting

Evaluation of the binding characteristics of [18F]FBVM in non-human primates a new radiotracer for imaging the vesicular acetylcholine transporter in vivo using positron emission tomography

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Evaluation of the binding characteristics of [18F]FBVM in non-human primates a new radiotracer for imaging the vesicular acetylcholine transporter in vivo using positron emission tomography

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Metabolomic & lipidomic information contained in Dried Blood Spot (DBS) vs. serum

International audienceDBS (Dried Blood Spot) are used for the screening of neonatal diseases and monitoring adults suffering from certain diseases in clinical context. DBS is a self-sampling device which is less invasive and requires less sample than a blood test. They can be sent by mail to the hospital allowing everyone to get access easily to biological analysis even in remote area or for elderly patients with mobility problems. Their use in new contexts has been widespread: carrying out anti-doping tests, the research of biomarkers of galactosemia or detection of cancer. In this work, we propose to compare quantitative data and exploratory metabolomic data between DSB and serum. For quantitative data, we quantified 6 short-chain fatty acids (SCFA), 20 bile acids, 20 tryptophan intermediates and 8 organic acids from TCA cycle. Two trends emerge: the first one is that the majority of the serum information is found in DBS. The second one is that DBS brings complementary information not found in serum. Indeed, an overlay of the metabolic cards of serum and DBS highlights a wider metabolic coverage for DBS. These results make it possible to envisage the use of DBS in both quantitative and exploratory metabolomic analyses. However, building up a cohort can last several months or years, so it will be necessary to clearly define the impact of storage conditions (temperature, hygrometry and light exposure) as well as its lasting

Metabolomic & lipidomic information contained in Dried Blood Spot (DBS) vs. serum

International audienceDBS (Dried Blood Spot) are used for the screening of neonatal diseases and monitoring adults suffering from certain diseases in clinical context. DBS is a self-sampling device which is less invasive and requires less sample than a blood test. They can be sent by mail to the hospital allowing everyone to get access easily to biological analysis even in remote area or for elderly patients with mobility problems. Their use in new contexts has been widespread: carrying out anti-doping tests, the research of biomarkers of galactosemia or detection of cancer. In this work, we propose to compare quantitative data and exploratory metabolomic data between DSB and serum. For quantitative data, we quantified 6 short-chain fatty acids (SCFA), 20 bile acids, 20 tryptophan intermediates and 8 organic acids from TCA cycle. Two trends emerge: the first one is that the majority of the serum information is found in DBS. The second one is that DBS brings complementary information not found in serum. Indeed, an overlay of the metabolic cards of serum and DBS highlights a wider metabolic coverage for DBS. These results make it possible to envisage the use of DBS in both quantitative and exploratory metabolomic analyses. However, building up a cohort can last several months or years, so it will be necessary to clearly define the impact of storage conditions (temperature, hygrometry and light exposure) as well as its lasting

radiotracer for imaging the vesicular acetylcholine transporter in vivo using positron emission tomography

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