Search

An analytical platform is required to characterize the short-chain fatty acids (SCFAs) in a mouse model of pathological immune conditions. Therefore, liquid chromatography tandem mass spectrometry combined with 2-picolylamine derivatization and a comprehensive study of SCFAs distribution based on serum, saliva, feces, liver, and brain from a mouse model of Sjögren's syndrome (SS) is performed. The design of experiments is used to achieve efficient 2-picolylamine derivatization, and optimize the reaction conditions. Twelve SCFAs are derivatized, and separated on a reversed-phase C 18 column. All SCFAs show high linearity (r 2  > 0.995) and intra/inter-day accuracy values from 71.6% to 115.6% (precision < 13.7%). This method was used to determine SCFAs concentrations in the serum, saliva, feces, liver, and brain of an SS model mice, and isobutyric acid, valeric acid, isovaleric acid, and 2-methylbutyric acid in liver from SS were significantly different compared with control group. Moreover, the preliminary evaluation of propionic acid, butyric acid, isobutyric acid, valeric acid, and isovaleric acid in saliva is conducted based on the respective SS stages and are correlated with these histological scores. This analytical platform for the widely SCFAs profiling in several tissues can be a clue for studying unclear immune pathophysiology., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

An efficient analytical platform is required to characterize the human metabolome in pathology. For this purpose, ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) combined with chemical derivatization stands out as one of the most powerful techniques. A targeted metabolomics platform for 11 bile acids (BAs) profiling in human serum and bile samples using a stable isotope labeling derivatization (SILD) was applied. For SILD, the design of experiments (DoE) was employed to optimize the reaction conditions such five factors in three levels. The sample preparation built upon a liquid-liquid extraction requiring small volumes (20 μL). In application, the relation between the BA and short-chain fatty acid levels in human serum and bile samples from patients with bile duct diseases were investigated. The proposed method offers significant utility in the large-scale biological analyses of hepato-biliary-pancreatic-related diseases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

We present a sensitive and selective method for the simultaneous determination of short-chain fatty acids (SCFAs), such as acetic acid (AA), propionic acid, butyric acid (BA), isobutyric acid, valeric acid, isovaleric acid, hydroangelic acid, caproic acid, 4-methylvaleric acid and succinic acid (SA) in feces samples using a ultra-high performance liquid-chromatography tandem mass spectrometry (UHPLC-MS/MS) with simple derivatization of 2-picolylamine. The main SFCAs were derivatized in the same condition, and showed the specific product ion (m/z 109) in the electrospray positive mode regarding to 2-picolylamine. The derivatized SA showed a different pattern of the product ion (m/z 191). The derivatized analytes showed LOD < 75 nM, LOQ < 100 nM and r 2 in the calibration curve > 0.991. The QuEChERS was used for sample preparation of feces samples. In the recovery test, the recovery values appeared from 89.7 to 100.2% (RSD: 2.1 to 9.2%, n = 6). This developed method was applied to evaluate obese diabetes model mice. In the result, the branched-chain SCFAs levels in feces from model mice of spontaneous obese type II diabetes were on a declining trend compared with normal. The AA levels from model mice with high-calorie/fat diet are owed a declining trend for 3 to 9 months. The BA levels showed that normal mice were increasing, and model mice had decreased tendency for breeding months. High-calorie/fat diet showed that the SA levels increased.