via Their Metabolic Profiling, Antioxidative, and Hypoglycemic Activities

Cichorium glandulosum Boiss. et Huet (CG) and Cichorium intybus L. (CI) are widely used as the main raw material of functional food with hepatoprotective and hypoglycemic effects. Due to the lack of comparison on the chemical ingredients and efficacy, they were often used imprecisely and interchangeably. It is necessary to distinguish between them. With the plant metabolomics based on high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) and multivariate chemometric techniques, the chemical ingredients were characterized and 59 compounds between CG and CI were classified. As for antioxidative and hypoglycemic activities in vitro, CI extraction exhibited better antioxidant activity than CG, while CG extraction showed stronger hypoglycemic activity. Furthermore, a bivariate correlation between the chemical composition and efficacy of the extract was also analyzed, and three differentially strong correlation components between CI and CG were prepared, and the antioxidative and hypoglycemic efficacies were compared in vivo and different active phenotypes were obtained. Finally, we revealed chemical and biological differences between CG and CI, providing a basis for achieving better quality control and developing more effective functional foods.

Involvement of Huanglian Jiedu Decoction on Microglia with Abnormal Sphingolipid Metabolism in Alzheimer's Disease

Background

Abnormal sphingolipid metabolism is closely related to the occurrence and development of Alzheimer’s disease (AD). With heat-clearing and detoxifying effects, Huanglian Jiedu decoction (HLJDD) has been used to treat dementia and improve learning and memory impairments.

Purpose

To study the therapeutic effect of HLJDD on AD as it relates to sphingolipid metabolism.

Methods

The level of sphingolipids in the brains of APP/PS1 mice and in the supernatant of β-amyloid (Aβ)_25–35-induced BV2 microglia was detected by HPLC-QTOF-MS and HPLC-QTRAP-MS techniques, respectively. The co-expression of ionized calcium-binding adapter molecule 1 (Iba1) and Aβ as well as four enzymes related to sphingolipid metabolism, including serine palmitoyltransferase 2 (SPTLC2), cer synthase 2 (CERS2), sphingomyelin phosphodiesterase 1 (SMPD1), and sphingomyelin synthase 1 (SGMS1), in the brains of APP/PS1 mice were evaluated by immunofluorescence double labelling. In addition, real-time quantitative reverse transcription-polymerase chain reaction was conducted to determine the mRNA expression of SPTLC2, CERS2, SMPD1, SGMS1, galactosylceramidase (GALC), and sphingosine kinase 2 (SPHK2) in Aβ_25-35-stimulated BV2 microglia.

Results

Abnormal sphingolipid metabolism was observed both in APP/PS1 mouse brain tissues and Aβ_25-35-stimulated BV2 cells. The levels of sphingosine, sphinganine, sphingosine-1-phosphate, sphinganine-1-phosphate and sphingomyelin were significantly reduced, while the levels of ceramide-1-phosphate, ceramide, lactosylceramide and hexosylceramide significantly increased in Aβ_25-35-stimulated BV2 cells. In AD mice, more microglia were clustered in the Aβ-positive region. The decreased level of SGMS1 and increased levels of CERS2, SPTLC and SMPD1 were also found. In addition, the expressions of SPTLC2, CERS2, and SMPD1 in Aβ_25-35-stimulated BV2 cells were increased significantly, while the expressions of GALC, SPHK2, and SGMS1 were decreased. These changes all showed a significant correction after HLJDD treatment.

Conclusion

HLJDD is a good candidate for treating AD. This study provides a novel perspective on the potential roles of the sphingolipid metabolism in AD.

Identification of alkaloidal compounds from leaves and roots of Stephania succifera by HPLC-QTOF-MS and prediction of potential bioactivity with PharmMapper

INTRODUCTION

The roots of Stephania succifera are used in traditional medicine for the treatment of several diseases. Research on this plant has mainly focused on bioactive alkaloids from the roots, and no previous work on compounds from the abundant leaves has yet been reported.

OBJECTIVE

To identify and compare alkaloidal compounds in S. succifera roots and leaves and to predict the potential bioactivity of some alkaloids.

METHODS

High-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS/MS) was employed to identify alkaloidal compounds from S. succifera. The potential targets and bioactivities of most alkaloids were predicted using the PharmMapper server.

RESULTS

Fifty-six alkaloidal compounds, including protoberberine-, aporphine-, proaporphine-, benzylisoquinoline-, and lactam-type alkaloids, were identified or tentatively identified in S. succifera roots and leaves based on the HPLC-MS data. Forty-one compounds have not been previously reported in S. succifera and eight of them have not been previously reported in the literature. Twenty-four alkaloidal compounds were found in both roots and leaves. Twelve potential targets with different indications were predicted for some alkaloids.

CONCLUSION

Comparison of chemical constituents and their potential bioactivities for S. succifera roots and leaves indicated that diverse bioactive alkaloids were present in the leaves as well as the roots. PharmMapper provided new directions for bioactivity screening. This study will be helpful for further understanding the medicinal components of S. succifera and the rational utilisation of plant resources.

Metabolite Profiling of Rosemary Cell Lines with Antiproliferative Potential against Human HT-29 Colon Cancer Cells

Rosemary (Rosmarinus officinalis) is a culinary and medicinal plant used in food and pharmaceutical industry. The wide range of biological activities is mainly related to phenolic and terpenic compounds; like carnosic acid (CA), carnosol (CS) and rosmarinic acid (RA), mainly reported in rosemary leaf extracts, and recently described in rosemary callus extracts. The aim of this work was to investigate the chemical profile of rosemary cell lines and evaluate their antiproliferative potential against human HT-29 colorectal cancer cell lines. For this purpose, rosemary leaf explants were dedifferentiated on MS medium and added with 2, 4-D (2, 4-dichlorophenoxyacetic acid; 2 mg/L) and BAP (6-benzylaminopurine; 2 mg/L). Cell aggregates were separated according to colour and three rosemary cell lines cultures were established: green (RoG), yellow (RoY) and white (RoW). The chemical profile of rosemary cell lines extracts was characterized by combining HPLC and GC platforms coupled to HR-MS/MS. The antiproliferative activity against HT-29 cell line was analyzed with MTT assay. A total of 71 compounds, including hydroxycinnamic acid and hydroxybenzoic acid derivatives, flavonoids, phenolic di- and triterpenes, as well as relevant unsaturated fatty acids and their esters, phytosterols, and carotenoids were tentatively identified in the extract of the target cell lines. The antiproliferative activity test against HT-29 cell using the MTT assay revealed that the viability of HT-29 colon cancer cells was affected after treatment with the RoW extract (IC50 of 49.63 μg/mL) at 48 h. These results showed that rosemary cell lines can also accumulate other bioactive phytochemicals with demonstrated antiproliferative potential.

Intervention of Ayurvedic drug Tinospora cordifolia attenuates the metabolic alterations in hypertriglyceridemia: a pilot clinical trial

Purpose

Hypertriglyceridemia (HG) is an independent risk factor with more prevalence than hypercholesterolemia and its attributes to cardiovascular disease (CVD) and pancreatitis. Hence, it becomes imperative to search for new triglyceride (TG) lowering agents. Tinospora cordifolia (TC) is a well-known Ayurvedic drug and a rich source of protoberberine alkaloids hence can contribute to TG lowering without side effects. Hence, to explore the therapeutic efficacy of T. cordifolia and its effects on biochemistry and metabolome in the patients of hyper-triglyceridemia, clinical trials were conducted.

Methods

Patients (n = 24) with hypertriglyceridemia were randomized into two groups to receive T. cordifolia extract (TCE) (3.0 g/per day) and metformin (850 mg/day) for 14 days having >300 mg/dl triglyceride level and cholesterol in the range of 130-230 mg/dl. Lipid profiles of blood samples were analyzed. Urine samples were subjected to HPLC-QTOF-MS to quantify oxidative damage and abnormal metabolic regulation.

Results

Intervention with TCE reduced the triglyceride, LDL, and VLDL levels to 380.45 ± 17.44, 133.25 ± 3.18, and 31.85 ± 5.88 mg/dL and increased the HDL to 47.50 ± 9.05 mg/dL significantly (p < 0.05) in the HG patients after 14 days treatment. TCE dosage potently suppressed the inflammatory and oxidative stress marker's i.e. levels of isoprostanes significantly (p < 0.01). Qualitative metabolomics approach i.e. PCA and PLS-DA showed significant alterations (p < 0.05) in the levels of 40 metabolites in the urine samples from different groups.

Conclusion

TCE administration depleted the levels of markers of HG i.e. VLDL, TG, and LDL significantly. Metabolomics studies established that the anti-HG activity of TCE was due to its antioxidative potential and modulation of the biopterin, butanoate, amino acid, and vitamin metabolism.

Clinical trials registry

India (CTRI) registration no. CTRI- 2016-08-007187.

Revealing the role of glycerophospholipid metabolism in asthma through plasma lipidomics

Lipid mediators play an essential role in the pathogenesis of asthma. Many studies on the differential expression of sphingolipids and fatty acid exist, but relatively few concerned about glycerophospholipid (GP) metabolites in asthma. Here, plasma samples from 20 healthy controls and 24 asthmatic patients were collected and analyzed. High-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) revealed that 29 GPs were identified and relatively quantified as differential metabolites for discriminating asthma patients and healthy subjects, consisting of six major subclasses of GPs. Moreover, a significant relevance was found between the selected metabolites and diagnostic and prognostic indicators of asthma. Remarkably, in subgroup analyses, plasma phosphatidic acid (PA), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) levels were higher in patients with eosinophilic asthma than non-eosinophilic asthma. Receiver-operating characteristic curve analysis revealed that the power of plasma PA and PG levels to distinguish between asthmatic patients and healthy subjects was strong (all areas under the curves > 0.9; P < 0.05). Our study characterized circulating GP metabolites in patients with asthma and explored their clinical relevance which may help to develop reliable biomarkers for early and accurate diagnosis based on lipid metabolites and provide novel insight into the role of GPs in asthma.

Comparison of Various Chromatographic Systems for Identification of Vortioxetine in Bulk Drug Substance, Human Serum, Saliva, and Urine Samples by HPLC-DAD and LC-QTOF-MS

Background: Determination of psychotropic drugs in clinical study is significant, and the establishment of methodologies for these drugs in biological matrices is essential for patients' safety. The search for new methods for their detection is one of the most important challenges of modern scientific research. The methods for analyzing of psychotropic drugs and their metabolites in different biological samples should be based on combining a very efficient separation technique including high-performance liquid chromatography (HPLC), with a sensitive detection method and effectively sample preparation methods. Objective: Retention, peaks symmetry and system efficiency of vortioxetine on Hydro RP, Polar RP, HILIC A (with silica stationary phase), HILIC-B (with aminopropyl stationary phase), and ACE HILIC-N (with polyhydroxy stationary phase and SCX columns were investigated. Various mobile phases containing methanol or acetonitrile as organic modifiers and different additives were also applied to obtained optimal retention, peaks shape, and systems efficiency. The best chromatographic procedure was used for simultaneous analysis of vortioxetine and its metabolites in human serum, urine and saliva samples. Methods: Analysis of vortioxetine was performed in various chromatographic systems: Reversed phase (RP) systems on alkylbonded or phenyl stationary phases, hydrophilic interaction liquid chromatography (HILIC), and ion-exchange chromatography (IEC). Based on the dependence of log k vs the concentration of the organic modifier, log kw values for vortioxetine in various chromatographic systems were determined and compared with calculated log P values. Solid phase extraction (SPE) method was applied for sample pre-treatment before HPLC analysis. HPLC-QTOF-MS method was applied for confirmation of presence of vortioxetine and some its metabolites in biological samples collected from psychiatric patient. Conclusions: Differences were observed in retention parameters with a change of the applied chromatographic system. The various properties of stationary phases resulted in differences in vortioxetine retention, systems' efficiency, and peaks' shape. Lipophilicity parameters were also determined using different HPLC conditions. The most optimal systems were chosen for the analysis of vortioxetine in biological samples. Both serum and urine or saliva samples collected from patients treated with vortioxetine can be used for the drug determination. For the first time, vortioxetine was detected in patient's saliva. Obtained results indicate on possibility of application of saliva samples, which collection are non-invasive and painless, for determination and therapeutic drug monitoring in patients.

Metabolomic profile perturbations of serum, lung, bronchoalveolar lavage fluid, spleen and feces in LPS-induced acute lung injury rats based on HPLC-ESI-QTOF-MS

Acute lung injury (ALI) is a clinically common and serious disease, underscoring the urgent need for clarification of its pathogenesis. According to traditional Chinese medicine (TCM) theories on the "lung-spleen-intestine axis" and its correlation with ALI, a high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) metabolomic platform was applied to identify biomarkers from five bio-samples of control and model rats challenged with intratracheally administered lipopolysaccharide (LPS) based on multivariate mathematical statistical analysis. As a result, 19, 24, 24, 15 and 29 altered metabolites were identified in serum, lung, bronchoalveolar lavage fluid (BALF), spleen and feces samples, respectively. Metabolic pathway analysis showed that linoleic acid, sphingolipid, glycerophospholipid and bile acid metabolism pathways were mainly altered by ALI. Additionally, ROC curves were applied to assess the specificity and sensitivity of the biomarkers. ALI characteristic metabolomic spectra were then established to differentiate the control from the model group with a similarity discriminative threshold of 0.7. Additionally, to compare the metabolomic profiles of the five bio-samples and establish metabolic similarities and differences among them, correlation analysis was conducted in order to delineate an objective law of endogenous linkage along the lung-spleen-intestine axis. Therefore, this study provides insights into the mechanisms involved in ALI from a metabolomics perspective, which can be applied in characterization of the mechanism and early disease detection. Graphical abstract.

Effects of chromatographic conditions and mass spectrometric parameters on the ionization and fragmentation of triterpene saponins of Ilex asprella in liquid chromatography-mass spectrometry analysis

High performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (HPLC-QTOF-MS) is widely used to qualitatively characterize the chemical profiles of herbal medicines, in which the generated adducts and fragments are crucial for confirming molecular ion (deprotonated/protonated ion) and deducing structure of detected components. However, how chromatographic and mass spectrometric (LC-MS) conditions/parameters affect the quantity and intensity of adducts and fragments of detected components is scarcely concerned. In present study, three types of triterpene saponins from the root of Ilex asprella (RIA) were selected as a case study to systematically investigate the effects of LC/MS conditions/parameters on their ionization and fragmentation, so as to obtain higher intensity (higher detection sensitivity) and quantity (rich information) of adducts and fragments for the characterization of components in RIA. It was found that for LC conditions, methanol as organic phase was more benefit for generating more adducts with higher intensity; formic acid as a modifier suppressed the formation of [M-2H]^2-, thus promoted the generation of other types of adducts at lower concentration but inhibited the generation when the concentration exceeded 0.1%. MS parameters affect scarcely the quantity but mainly intensity of adducts, cone voltage, source temperature and desolvation gas flow have relatively higher impacts when compared with other parameters. Collision energy affected both quantity and intensity of fragments. MS parameters at the medium value largely increased the quantity and intensity of adducts and fragments. Three-types of triterpene saponins presented structurally specific ionization and fragmentation due to their amounts of acidic substitutes. A total of 55 components were detected and definitely or tentatively identified in RIA under the optimized LC-MS conditions, among which 35 triterpene saponins were firstly discovered. This is the first report that proposes and validates a systematic approach for assessing the effects of LC/MS conditions/parameters on the ionization and fragmentation of analytes, which could be helpful for the optimization of LC-MS conditions for effective chemical profiling analysis of herbal medicines.

Optimization of the Data Treatment Steps of a Non-targeted LC-MS-Based Workflow for the Identification of Trace Chemical Residues in Honey

Non-targeted screening (e.g., suspected-target) is emerging as an attractive tool to investigate the occurrence of contaminants in food. The sample preparation and instrument analysis steps are known to influence the identification of analytes with non-targeted workflows, especially for complex matrices. However, for methods based on mass spectrometry, the impact of the post-analysis data treatment (e.g., feature extraction) on the capacity to correctly identify a contaminant at trace level is currently not well understood. The aim of the study was to investigate the influence of seven post-analysis data treatment parameters on the non-targeted identification of trace contaminants in honey using high-performance liquid chromatography coupled to hybrid quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS). Seven compounds reported as veterinary drugs for honeybees were applied as model compounds. Among the parameters studied, the expansion window for chromatogram extraction and the average scans included in the spectra influenced significantly the identification process results. The optimized data treatment was applied to the non-targeted screening of veterinary drugs, pesticides, and other contaminants in 55 honey samples as a proof of concept. Among the 43 compounds included in a library of honey-related compounds that was used for screening, eight compounds were tentatively identified in at least one honey sample. The tentative identity of two of these compounds (tylosin A and hydroxymethylfurfural) was further confirmed with analytical standards. Graphical Abstract.

Investigating Stability and Tautomerization of Gossypol-A Spectroscopy Study

The stability of gossypol was investigated by the spectroscopic method. Gossypol was dissolved in three different solvents (CHCl₃, DMSO, and CH₃OH) under different storage conditions (dark and with nitrogen protection, natural light and with nitrogen protection, ambient air conditions) for different time intervals (0 days, 3 days, 5 days, 7 days, 15 days, 30 days, and 45 days) at room temperature. Then, the stability of gossypol was investigated by ¹H NMR, UV-vis, and HPLC-QTOF-MS spectrometry. Results showed that gossypol existed in aldehyde–aldehyde form in chloroform within five days. Then, both aldehyde–aldehyde and lactol–lactol tautomeric forms existed and maintained a stable solution for 45 days. Gossypol dissolved in methanol mainly existed in aldehyde–aldehyde form. Only a tiny amount of lactol–lactol was found in freshly prepared methanol solution. Gossypol was found to only exist in lactol–lactol form between 30–45 days. Gossypol existed in aldehyde–aldehyde, lactol–lactol, and ketol–ketol forms in dimethyl sulfoxide, and there was a competitive relationship between aldehyde–aldehyde and lactol–lactol form during the 45 days. Among all the solvents and conditions studied, gossypol was found to be highly stable in chloroform. Under the tested conditions, the natural light and atmospheric oxygen had little effect on its stability. Although the spectroscopy data seemed to be changed over time in the three different solvents, it was actually due to the tautomeric transformation rather than molecular decomposition.

Metabolomics Characterizes the Effects and Mechanisms of Quercetin in Nonalcoholic Fatty Liver Disease Development

As metabolomics is widely used in the study of disease mechanisms, an increasing number of studies have found that metabolites play an important role in the occurrence of diseases. The aim of this study is to investigate the effects and mechanisms of quercetin in high-fat-sucrose diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) development using nontargeted metabolomics. A rat model of NAFLD was established by feeding with an HFD for 30 and 50 days. The results indicated quercetin exhibited hepatoprotective activity in 30-day HFD-induced NAFLD rats by regulating fatty acid related metabolites (adrenic acid, etc.), inflammation-related metabolites (arachidonic acid, etc.), oxidative stress-related metabolites (2-hydroxybutyric acid) and other differential metabolites (citric acid, etc.). However, quercetin did not improve NAFLD in the 50-day HFD; perhaps quercetin was unable to reverse the inflammation induced by a long-term high-fat diet. These data indicate that dietary quercetin may be beneficial to NAFLD in early stages. Furthermore, combining metabolomics and experimental approaches opens avenues to study the effects and mechanisms of drugs for complex diseases.

Comparison of Bioactive Compounds and Antioxidant Activities of Maclura tricuspidata Fruit Extracts at Different Maturity Stages

Maclura tricuspidata fruit contains various bioactive compounds and has traditionally been used in folk medicine and as valuable food material in Korea. The composition and contents of bioactive compounds in the fruit can be influenced by its maturity stages. In this study, total phenol, total flavonoid, individual polyphenolic compounds, total carotenoids and antioxidant activities at four maturity stages of the fruit were determined. Polyphenolic compounds were analyzed using high-pressure liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF-MS) and HPLC. Among 18 polyphenolic compounds identified in this study, five parishin derivatives (gastrodin, parishin A, B, C, E) were positively identified for the first time in this plant. These compounds were also validated and quantified using authentic standards. Parishin A was the most abundant component, followed by chlorogenic acid, gastrodin, eriodictyol glucoside, parishin C, parishin E and parishin B. The contents of all the polyphenolic compounds were higher at the immature and premature stages than at fully mature and overmature stages, while total carotenoid was found to be higher in the mature and overmature stages. Overall antioxidant activities by three different assays (DPPH, ABTS, FRAP) decreased as maturation progressed. Antioxidant properties of the fruit extract are suggested to be attributed to the polyphenols.

Efficient Discovery of Quality Control Markers for Gastrodia elata Tuber by Fingerprint-Efficacy Relationship Modelling

INTRODUCTION

Gastrodia elata tuber (GET) has been widely used in China as a famous herbal medicine. However, the quality control markers (QCMs) for GET still need further investigation.

OBJECTIVE

To develop a rational strategy based on fingerprint-efficacy relationship modelling to discover the efficacy-related QCMs, using GET as a case study.

METHODOLOGY

The high-performance liquid chromatography (HPLC) fingerprints of 13 batches of GET extracts were established and 10 common peaks were structurally characterised by HPLC coupled with quadrupole time-of-flight mass spectrometry (QTOF-MS). The neuroprotective effects of GET samples were evaluated using the in vitro model of β-amyloid peptide (Aβ_25-35 )-induced PC12 cell death. The fingerprint-efficacy relationship of chemical fingerprints and neuroprotective effects was linked by orthogonal projection to latent structure-discriminant analysis (OPLS-DA) model.

RESULTS

The chemical combination of 5-hydroxymethyl-2-furaldehyde (5-HMF), parishin B (PB) and parishin C (PC) was discovered and confirmed as QCMs of GET by the OPLS-DA method. The selected QCMs allowed to evaluate the relative quality of GET samples.

CONCLUSION

This study has demonstrated that the rational strategy based on fingerprint-efficacy relationship modelling might be generally applicable for the quality control of herbal medicines. Copyright © 2017 John Wiley & Sons, Ltd.

Effects of breviscapine on amyloid beta 1-42 induced Alzheimer's disease mice: A HPLC-QTOF-MS based plasma metabonomics study

Herba Erigerontis has long been used to cure apoplexy hemiplegia and precordial pain in China. In addition, the bioactivities of its total flavonoids-breviscapine included inhibiting amyloid beta (Aβ) fibril formation, antioxidation and metal chelating, which are beneficial to treat Alzheimer's disease (AD). Hence, A HPLC-QTOF-MS based plasma metabonomics approach was applied to investigate the neuroprotective effects of breviscapine on intracerebroventricular injection of aggregated Aβ 1-42 induced AD mice for the first time in the study. Ten potential biomarkers were screened out by multivariate statistical analysis, eight of which were further identified as indoleacrylic acid, C16 sphinganine, LPE (22:6), sulfolithocholic acid, LPC (16:0), PA (22:1/0:0), taurodeoxycholic acid, and PC (0:0/18:0). According to their metabolic pathways, it was supposed that breviscapine ameliorated the learning and memory deficits of AD mice predominantly by regulating phospholipids metabolism, elevating serotonin level and lowering cholesterols content in vivo.

Nonylphenol Toxicity Evaluation and Discovery of Biomarkers in Rat Urine by a Metabolomics Strategy through HPLC-QTOF-MS

Nonylphenol (NP) was quantified using liquid chromatography tandem mass spectrometry (LC-MS/MS) in the urine and plasma of rats treated with 0, 50, and 250 mg/kg/day of NP for four consecutive days. A urinary metabolomic strategy was originally implemented by high performance liquid chromatography time of flight mass spectrometry (HPLC-QTOF-MS) to explore the toxicological effects of NP and determine the overall alterations in the metabolite profiles so as to find potential biomarkers. It is essential to point out that from the observation, the metabolic data were clearly clustered and separated for the three groups. To further identify differentiated metabolites, multivariate analysis, including principal component analysis (PCA), orthogonal partial least-squares discriminant analysis (OPLS-DA), high-resolution MS/MS analysis, as well as searches of Metlin and Massbank databases, were conducted on a series of metabolites between the control and dose groups. Finally, five metabolites, including glycine, glycerophosphocholine, 5-hydroxytryptamine, malonaldehyde (showing an upward trend), and tryptophan (showing a downward trend), were identified as the potential urinary biomarkers of NP-induced toxicity. In order to validate the reliability of these potential biomarkers, an independent validation was performed by using the multiple reaction monitoring (MRM)-based targeted approach. The oxidative stress reflected by urinary 8-oxo-deoxyguanosine (8-oxodG) levels was elevated in individuals highly exposed to NP, supporting the hypothesis that mitochondrial dysfunction was a result of xenoestrogen accumulation. This study reveals a promising approach to find biomarkers to assist researchers in monitoring NP.