Nuclear magnetic resonance‐ and mass spectrometry‐based metabolomics to study maleic acid toxicity from repeated dose exposure in rats

Abstract

We recently found the Figure S1 presented in the supplemental materials of our paper (Wu et al., 2017) may not be the most representative chromatogram generated from the analysis of four oxidative stress biomarkers (8-NO2Gua, 8-OHdG, HNE-MA and 8-isoPGF2α) from rat urine samples collected from repeated exposure to maleic acid in this study. The figure was put in the method section intended to demonstrate the feasibility of our analytical platform, which was cited and had been applied in previous research (Chen, Yuan, Shie, Wu, & Chan, 2017; Wu, Chen, Peng, Cheng, & Wu, 2016). Upon combing through our experimental raw data, this replacement chromatogram is more appropriate to include in the supplemental materials of this paper. In this diagram, only the four analytes and their respective isotopes are additionally marked. The corrected figure is provided in the Supporting Information. The replacement of this new figure in the supplementary material does not affect the main text and results of this paper. We apologize for the inconvenience that this replacement caused by this mistake. Table S1. The HPLC system comprised a quaternary pump, an autosampler, and a 3 μm, 100×2 mm Gemini-NX-C18 analytical column (Phenomenex, Torrance, CA). Table S2. Body weight gain and relative organ weights in low dose (LD), medium dose (MD), high dose (HD) group and the control group Figure S1. A representative chromatogram of four urinary oxidative stress biomarkers from a rat dosed with 60 mg/kg of maleic acid on day 14. Figure S2. The histopathology results of a representative frozen section of rat kidney from the (a) control and (b) high-dose (60 mg/kg) groups which treated with maleic acid daily for 28 days. Figure S3. The histopathology results of a representative frozen section of rat liver from the (a) control and (b) high-dose (60 mg/kg) groups which treated with maleic acid daily for 28 days Figure S4. A representative NMR spectrum of urinary metabolic profiling performed by 600 MHz 1H NMR from rats treated with maleic acid (high-dose) daily. Figure S5. PCA (a) scores plot from the analysis of 1H NMR spectra of urine collected from day and night from rats treated with control or maleic acid exposure; (b) loading plot from the analysis of 1H NMR spectra of urine collected from day and night from rats treated with control or maleic acid exposure. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.