Integrated Metabolomics Approach Research Articles

Integrated Metabolomics Approach Reveals the Dynamic Variations of Metabolites and Bioactivities in Paeonia ostii 'Feng Dan' Leaves during Development.

Paeonia ostii 'Feng Dan' is widely cultivated in China for its ornamental, medicinal, and edible properties. The whole plant of tree peony is rich in bioactive substances, while the comprehensive understanding of metabolites in the leaves is limited. In this study, an untargeted metabolomics strategy based on UPLC-ESI-TOF-MS was conducted to analyze the dynamic variations of bioactive metabolites in P. ostii 'Feng Dan' leaves during development. A total of 321 metabolites were rapidly annotated based on the GNPS platform, in-house database, and publications. To accurately quantify the selected metabolites, a targeted method of HPLC-ESI-QQQ-MS was used. Albiflorin, paeoniflorin, pentagalloylglucose, luteolin 7-glucoside, and benzoylpaeoniflorin were recognized as the dominant bioactive compounds with significant content variations during leaf development. Metabolite variations during the development of P. ostii 'Feng Dan' leaves are greatly attributed to the variations in antioxidant activities. Among all tested bacteria, the leaf extract exhibited exceptional inhibitory effects against Streptococcus hemolytis-β. This research firstly provides new insights into tree peony leaves during development. The stages of S1-S2 may be the most promising harvesting time for potential use in food or pharmaceutical purposes.

Unravelling dynamic changes in non-volatile and volatile metabolites of pulses during soaking: An integrated metabolomics approach.

An integrated metabolomics approach based on UPLC-QTOF-MS and HS-SPME-GC-orbitrap-MS was performed to investigate the dynamic changes of metabolite profiling in chickpeas, red speckled kidney beans, and mung beans during soaking. There were 23, 23, 16 non-volatile metabolites, and 18, 21, 22 volatile metabolites were identified as differential metabolites in chickpeas, red speckled kidney beans, and mung beans during soaking, respectively. These metabolites mainly included flavonoids, lysophosphatidylcholines (LPCs), lysophosphatidylethanolamines (LPEs), fatty acids, alcohols, aldehydes, and esters. The key time points responsible for the significant changes in metabolites and quality of the three pulses were 4, 8, and 24h of soaking. Results revealed that the variations of some metabolites could attribute to oxidation and hydrolysis reactions. These results contribute to a better understanding of how soaking affects pulses quality, and provide useful information for determining soaking time according to nutritional and sensory requirements of their final products or dishes.

The Impact of Metallic Nanoparticles on Gut Fermentation Processes: An Integrated Metabolomics and Metagenomics Approach Following in Vitro Digestion and Fermentation Model

The Impact of Metallic Nanoparticles on Gut Fermentation Processes: An Integrated Metabolomics and Metagenomics Approach Following in Vitro Digestion and Fermentation Model

Hepatotoxicity or hepatoprotection of emodin? Two sides of the same coin by 1H-NMR metabolomics profiling

Emodin is the major anthraquinone component of many important traditional Chinese herbs, such as Rheum palmatum L. and Polygonum multiflorum Thunb. They have been popular health products but recently aroused concerns about their hepatotoxicity, which are believed to be arising from the contained anthraquinones, such as emodin. However, emodin exerts potent hepatoprotective ability, such as anti-fibrotic, anti-oxidative, and anti-inflammatory effects. In this study, 1H NMR based metabolomics approach, complemented with histopathological observation, biochemical measurements, western blotting analysis and real-time quantitative PCR (RT-qPCR), was applied to interpret the paradox of emodin (30 mg/kg, 10 mg/kg BW) using both healthy mice (male, ICR) and chronic CCl4-injured mice (0.1 mL/kg, 0.35% CCl4, 3 times a week for a month). Emodin exerted a weight loss property associated with its lipid-lowing effects, which helped alleviate CCl4-induced steatosis. Emodin effectively ameliorated CCl4-induced oxidative stress and energy metabolism dysfunction in mice liver via regulating glucose, lipid and amino acid metabolism, and inhibited excessive inflammatory response. In healthy mice, emodin only exhibited hepatoxicity on high-dosage by disturbing hepatic anti-oxidant homeostasis, especially GSH and xanthine metabolism. This integrated metabolomics approach identified the bidirectional potential of emodin, which are important for its rational use.

Huanglian Jiedu decoction remodels the periphery microenvironment to inhibit Alzheimer\u2019s disease progression based on the \u201cbrain-gut\u201d axis through multiple integrated omics

BackgroundIn recent years, excellent results have suggested an association between the “brain-gut” axis and Alzheimer’s disease (AD) progression, yet the role of the “brain-gut” axis in AD pathogenesis still remains obscure. Herein, we provided a potential link between the central and peripheral neuroinflammatory disorders in AD progression.MethodsThe Morris water maze (MWM) test, immunohistochemistry, ELISA, ProcartaPlex Multiplex immunoassay, multiple LC-MS/MS methods, and the V3-V4 regions of 16S rRNA genes were applied to explore potential biomarkers.ResultsIn Tg-APP/PS1 mice, gut dysbiosis and lipid metabolism were highly associated with AD-like neuroinflammation. The combination of inflammatory factors (IL-6 and INF-γ), phosphatidylcholines (PCs) and SCFA-producing bacteria were expected to be early diagnostic biomarkers for AD. Huanglian Jiedu decoction (HLJDD) suppressed gut dysbiosis and the associated Aβ accumulation, harnessed neuroinflammation and reversed cognitive impairment.ConclusionTogether, our findings highlighted the roles of neuroinflammation induced by gut dysbiosis and lipid metabolism disorder in AD progression. This integrated metabolomics approach showed its potential to understand the complex mechanisms of HLJDD in the treatment of AD.

Therapeutic assessment of fractions of Gastrodiae Rhizoma on chronic atrophic gastritis by 1H NMR-based metabolomics

Ethnopharmacological relevanceGastrodiae Rhizoma (GR), a well-known and commonly-used TCM (Traditional Chinese Medicine) for treating headache, dizziness, tetanus, epilepsy, and etc., has been proven to relieve chronic atrophic gastritis (CAG). Due to its complex ingredients, the active fractions responsible for the treatment of CAG remain largely unknown. Aim of the studyTo explore the underlying material and interpret its underlying mechanism, the therapeutic effect of extract from different polar parts of Gastrodiae Rhizoma on autoimmune CAG was studied based on the 1H NMR metabolomics. Materials and methodsThe rat model of CAG was established by autoimmune method. The modeled CAG rats were then treated with 4 polar parts (T1-4 in descending polarity, corresponding to water, n-butanol, ethyl acetate and petroleum ether extracts, respectively) of Gastrodiae Rhizoma for 21 consecutive days. The stomach and serum samples were collected and then subjected to histopathology observation, biochemical measurement (MDA, SOD, GSH, NO, XOD and pepsin), 1H NMR metabolic profiling and multivariate/univariate statistical analysis. ResultsThe results showed that T1 had the best therapeutic effect, T2 the second, and T3 and T4 the poorest with no obvious therapeutic effect, demonstrating that the effective components of Gastrodiae Rhizoma should be compounds of high polarity. T1 achieved good therapeutic effects due to the anti-inflammatory and anti-oxidant activities, and by rectifying the disturbed energy and amino acid metabolism in CAG model. ConclusionThis integrated metabolomics approach proved the validity of the therapeutic effect of extract from different polar parts of Gastrodiae Rhizoma on autoimmune CAG, providing new insights into the underlying mechanisms, and demonstrating the feasibility of metabolomics to evaluate efficacy of herbal drug, which is often difficult by traditional means.

A metabolomic study on the anti-depressive effects of two active components from Chrysanthemum morifolium

Chrysanthemum morifolium (Chr) is a traditional Chinese medicine (TCM) that has been used in the treatment of inflammation-linked diseases for hundreds of years. Naringenin (Nar) and apigenin (Api) are the major active components in aqueous extracts of C. morifolium. The aim of our study was to clarify the roles of Chr, Nar and Api in ameliorating depression-like behaviour induced by corticosterone. First, the behavioural and biochemical indicators closely related to depression were examined to evaluate the therapeutic effects of Chr/Nar/Api on a depression model. Then, a metabolomics approach was utilized to screen for biomarkers and related pathways between a control group and Chr/Nar/Api groups. The comprehensive results revealed that Chr/Nar/Api exerted anti-depressant effects through interfering with tryptophan metabolism, arginine and prolinemetabolism, citrate cycle, niacin and niacinamide metabolism, phenylalanine metabolism, and alanine, aspartate and glutamate metabolism. The mechanism of Chr/Api/Nar in the treatment of depression was elucidated based on material and energy metabolism. Moreover, Nar could be used as a substitute for Chr for reversing depression-like behaviour, and Api was similar to a positive drug in terms of function on depression. The integrated metabolomics approach demonstrated here should be an effective method for interpreting the function of herbs from TCM and clarifying the mechanism of their components in future studies.

Hepatoprotection of Herpetospermum caudigerum Wall. against CCl4-induced liver fibrosis on rats

Ethnopharmacological relevanceHerpetospermum caudigerum Wall. (HCW) is a traditional Tibetan medicine, which has been used to ameliorate liver injuries in the folk. Aim of the studyLiver fibrosis has been recognized as a major lesion of the liver that leads to liver cirrhosis/hepatocarcinoma and even to death in the end. This study aims to demonstrate the protective effect of HCW against CCl4-induced liver injury in rats and to explore the underlying mechanisms. Materials and methodsHepatic fibrosis was induced by intraperitoneal injection of CCl4. Liver function markers, fibrosis markers, serum anti-oxidation enzymes as well as elements levels were determined. Serum and liver tissues were subjected to NMR-based metabolomics and multivariate statistical analysis. ResultsHCW could significantly reduce the elevated levels of fibrosis markers such as hyaluronidase, laminin, Type III procollagen and Type IV collagen in the serum, improve the activities of the antioxidant enzymes, and effectively reverse the abnormal levels of elements in liver fibrosis rats. Correlation network analysis revealed that HCW could treat liver fibrosis by ameliorating oxidative stress, repairing the impaired energy metabolisms and reversing the disturbed amino acids and nucleic acids metabolisms. ConclusionThis integrated metabolomics approach confirmed the validity of the traditional use of HCW in the treatment of liber fibrosis, providing new insights into the underlying mechanisms.

Tibetan Medical Formula Shi-Wei-Gan-Ning-Pill Protects Against Carbon Tetrachloride-Induced Liver Fibrosis - An NMR-Based Metabolic Profiling.

Liver fibrosis is a severe health problem, threatening the life quality and causing death, raising great concerns worldwide. Shi-Wei-Gan-Ning-Pill (SWGNP) is a traditional Tibetan recipe used to treat hepatic injuries; however, its hepatoprotective mechanism has not yet fully clarified. In this study, histological staining, biochemical assays, and elements determination were applied to evaluate the anti-fibrotic efficacy of SWGNP on a carbon tetrachloride (CCl4) induced hepato-fibrosis rat model. NMR-based metabolomics combined with orthogonal partial least squares-discriminant analysis (OPLS-DA), canonical regression analysis, and correlation networks analysis was used to characterize the potential biomarkers as well as metabolic pathways associated with the hepatoprotective activity of SWGNP. The results showed that SWGNP could significantly attenuate the pathological changes and decrease the levels of fibrosis markers (ColIV, HA, LN, and PCIII), and regulate the disordered elements distribution. Multivariate analysis and correlation network analysis revealed that SWGNP could protect rats against CCl4-induced liver fibrosis through anti-oxidation, repairing the impaired energy metabolisms and reversing the disturbed amino acids and nucleic acids metabolisms. In conclusion, this integrated metabolomics approach provided new insights into the mechanism of the hepatoprotective effect of SWGNP in liver fibrosis disease.

Isoniazid-induced hepatotoxicity and neurotoxicity in rats investigated by 1H NMR based metabolomics approach

Isoniazid (INH) is a well-known therapeutic and preventive agent against tuberculosis. However, high rates of side effects with various symptoms concerning hepatotoxicity and neurotoxicity have been reported, hindering its wide and safe application in clinic. In this investigation, rats were intoxicated with INH by gavage at doses of 200 and 400 mg/kg for 7 consecutive days to develop a rat model of acute INH-induced toxicity, which was investigated by a 1H NMR-based metabolomics complemented with clinical assays, histopathological inspection and western blotting. INH decreased the weights of dosed rats and induced seizure and hepatic steatosis dose-dependently. Orthogonal signal correction partial least-squares discriminant analysis (OSC-PLS-DA) of the NMR profiles of rat livers, brains and serum revealed that INH dose-dependently induced oxidative stress, disorders of excitatory and inhibitory amino acid neurotransmitters, and disturbances of energy metabolism and osmotic balance, which could help clarify the mechanisms of INH-induced hepatotoxicity and neurotoxicity. This integrated metabolomics approach showcased its ability to characterize the global metabolic status of organism, providing a powerful and feasible tool to probe drug induced toxicity or side effects.

Metabolic switching in the hypoglycemic and antitumor effects of metformin on high glucose induced HepG2 cells

Metformin, a widely prescribed drug for the management of type 2 diabetes mellitus, has potential anticancer effect. Diabetes patients regularly taking metformin have been reported with decreased cancer risk and improved cancer prognosis in recent years. A cell model of high glucose induced HepG2 cells was conducted to mimic insulin resistance, and a 1H NMR-based metabolomics approach in conjunction with molecular biology was performed to investigate the metabolic changes of high glucose induced HepG2 cells in response to different doses of metformin treatment and to study the differences and links between hypoglycemic and antitumor effects of metformin. Metformin with hypoglycemic effect rectified glucose metabolic imbalance and regulated oxidative stress, energy and amino acid metabolism. Metformin inhibited tumor cell proliferation and induced apoptosis through activation of AMPK/mTOR pathway and further influencing energy metabolism, phospholipid metabolism and glucose catabolism. The integrated metabolomics approach showed its potential in clarifying the different action on metformin treatment and understanding the pleiotropic effect of metformin.

Comparative and integrative metabolomics reveal that S-nitrosation inhibits physiologically relevant metabolic enzymes

Cysteine S-nitrosation is a reversible post-translational modification mediated by nitric oxide (•NO)-derived agents. S-Nitrosation participates in cellular signaling and is associated with several diseases such as cancer, cardiovascular diseases, and neuronal disorders. Despite the physiological importance of this nonclassical •NO-signaling pathway, little is understood about how much S-nitrosation affects protein function. Moreover, identifying physiologically relevant targets of S-nitrosation is difficult because of the dynamics of transnitrosation and a limited understanding of the physiological mechanisms leading to selective protein S-nitrosation. To identify proteins whose activities are modulated by S-nitrosation, we performed a metabolomics study comparing WT and endothelial nitric-oxide synthase knockout mice. We integrated our results with those of a previous proteomics study that identified physiologically relevant S-nitrosated cysteines, and we found that the activity of at least 21 metabolic enzymes might be regulated by S-nitrosation. We cloned, expressed, and purified four of these enzymes and observed that S-nitrosation inhibits the metabolic enzymes 6-phosphogluconate dehydrogenase, Δ1-pyrroline-5-carboxylate dehydrogenase, catechol-O-methyltransferase, and d-3-phosphoglycerate dehydrogenase. Furthermore, using site-directed mutagenesis, we identified the predominant cysteine residue influencing the observed activity changes in each enzyme. In summary, using an integrated metabolomics approach, we have identified several physiologically relevant S-nitrosation targets, including metabolic enzymes, which are inhibited by this modification, and we have found the cysteines modified by S-nitrosation in each enzyme.

Protective effects of Polygonum multiflorum on ischemic stroke rat model analysed by 1H NMR metabolic profiling

Stroke is the third most common cause of death in most industrialized countries. Polygonum multiflorum (He-Shou-Wu, HSW) is one of the traditional Chinese medicines with multiple pharmacological activities which is widely used in Chinese recipe. This study aims to explore the protective effect of HSW on ischemic stroke rat model and to elucidate the underlying mechanisms. The mortality rate, neurological deficit, cerebral infarct size, histopathology, immunohistochemistry, biochemical parameters, quantitative real-time polymerase chain reaction and western blotting were used to access the treatment effects of HSW on ischemic stroke. Proton nuclear magnetic resonance (1H NMR) based metabolomics analysis disclosed that HSW could relieve stroke rats suffering from the ischemia/reperfusion injury by ameliorating the disturbed energy and amino acids metabolisms, alleviating the oxidative stress from reactive oxygen species and reducing the inflammation. HSW treatment increased levels of cellular antioxidants that scavenged reactive oxygen species during ischemia-reperfusion via the nuclear erythroid 2-related factor 2 signaling pathway, and exert anti-inflammatory effect by decreasing the levels of inflammatory factors such as cyclooxygenase-2, interleukin-1β, interleukin-6 and tumor necrosis factor-α. The integrated metabolomics approach showed its potential in understanding mechanisms of HSW in relieving ischemic stroke. Further study to develop HSW as an effective therapeutic agent to treat ischemic stroke is warranted.

Antifungal Activity of Ramulus cinnamomi Explored by 1H-NMR Based Metabolomics Approach

A 1H nuclear magnetic resonance (NMR)-based approach to metabolomics combined bioassay was used to elucidate the antifungal activity of cinnamaldehyde (the main active compound of Ramulus cinnamomi) isolated from Ramulus cinnamomi (RC). Orthogonal signal correction partial least-squares discriminant analysis (OSC-PLS-DA) of NMR data was constructed to analyze all the P. italicum data acquired from the control and treatment groups at 4, 8, and 12 h. Metabolic profiles disclosed metabolic changes that were related to the antifungal effects of cinnamaldehyde against P. italicum including oxidative stress, disorder of energy metabolism, amino acids, and nucleic acids metabolism in treatment group. This integrated metabolomics approach provided an effective way to detect the antifungal effects of cinnamaldehyde against P. italicum dynamically.

Investigation of Dioscorea bulbifera Rhizome-Induced Hepatotoxicity in Rats by a Multisample Integrated Metabolomics Approach.

The use of herbal medicines continues to expand globally, meanwhile, herb-associated hepatotoxicity is becoming a safety issue. As a conventional Chinese medicinal herb, Dioscorea bulbifera rhizome (DBR) has been documented to cause hepatic toxicity. However, the exact underlying mechanism remains largely unexplored. In the present study, we aimed to profile entire endogenous metabolites in a biological system using a multisample integrated metabolomics strategy. Our findings offered additional insights into the molecular mechanism of the DBR-induced hepatotoxicity. We identified different metabolites from rat plasma, urine, and feces by employing gas chromatography-mass spectrometry in combination with multivariate analysis. In total, 55 metabolites distributed in 33 metabolic pathways were identified as being significantly altered in DBR-treated rats. Correlation network analysis revealed that the hub metabolites of hepatotoxicity were mainly associated with amino acid, bile acid, purine, pyrimidine, lipid, and energy metabolism. As such, DBR affected the physiological and biological functions of liver via the regulation of multiple metabolic pathways to an abnormal state. Notably, our findings also demonstrated that the multisample integrated metabolomics strategy has a great potential to identify more biomarkers and pathways in order to elucidate the mechanistic complexity of toxicity of traditional Chinese medicine.

Metabolic profiling of goldfish (Carassius auratis) after long-term glyphosate-based herbicide exposure

Glyphosate is an efficient herbicide widely used worldwide. However, its toxicity to non-targeted organisms has not been fully elucidated. In this study, the toxicity of glyphosate-based herbicide was evaluated on goldfish (Carassius auratus) after long-term exposure. Tissues of brains, kidneys and livers were collected and submitted to NMR-based metabolomics analysis and histopathological inspection. Plasma was collected and the blood biochemical indexes of AST, ALT, BUN, CRE, LDH, SOD, GSH-Px, GR and MDA were measured. Long-term glyphosate exposure caused disorders of blood biochemical indexes and renal tissue injury in goldfish. Metabolomics analysis combined with correlation network analysis uncovered significant perturbations in oxidative stress, energy metabolism, amino acids metabolism and nucleosides metabolism in glyphosate dosed fish, which provide new clues to the toxicity of glyphosate. This integrated metabolomics approach showed its applicability in discovering the toxic mechanisms of pesticides, which provided new strategy for the assessment of the environmental risk of herbicides to non-target organisms.

Optimization of Huang-Lian-Jie-Du-Decoction for Ischemic Stroke Treatment and Mechanistic Study by Metabolomic Profiling and Network Analysis.

Optimal drug proportions and mechanism deciphering of multicomponent drugs are critical for developing novel therapies to cope with complex diseases, such as stroke. In the present study, orthogonal experimental design was applied to explore the optimal proportion of the four component herbs in Huang-Lian-Jie-Du-Decoction (HLJDD) on the treatment of ischemic stroke. The treatment efficacies and mechanisms were assessed using global and amino acids (AAs) targeted metabolomics, as well as correlation network analysis. The global NMR metabolomics results revealed that AAs metabolism was significantly perturbed in middle cerebral artery occlusion rats. The levels of 23 endogenous AAs were then subjected to HPLC-QTOF-MS/MS analysis. These results complemented with neurobehavioral evaluations, cerebral infarct assessments, biochemical evaluations, histological inspections and immunohistochemistry observations strongly demonstrated that HLJDD with optimal proportion of 6 (Rhizoma coptidis): 4 (Radix scutellariae): 1 (Cortex phellodendr): 3 (Fructus Gardeniae) had the best efficacy on ischemic stroke, which could be ascribed to its modulation on AA metabolism. This integrated metabolomics approach showed the potential and applicable in deciphering the complex mechanisms of traditional Chinese medicine formulae on the treatment of complicated diseases, which provided new means to assess the treatment effects of herb combinations and to further development of drugs or therapies based on these formulae.

A metabolomics approach to elucidate apple fruit responses to static and dynamic controlled atmosphere storage

The response of apple fruit to storage conditions based on low oxygen protocols depends on their genetic background. In order to elucidate common and divergent processes characterizing the metabolic changes under hypoxia, fruit of two apple (Malus domestica) varieties (‘Granny Smith’, GS, and ‘Red Delicious’, RD) were stored under two different low oxygen protocols (Ultra Low Oxygen, ULO, at 0.9kPa oxygen, and Dynamic Controlled Atmosphere based on chlorophyll fluorescence, DCA-CF, between 0.2 and 0.55kPa oxygen) for up to 200 and 214days of storage for GS and RD samples, respectively. Through an integrated metabolomics approach (1H NMR, GC–MS, HS-SPME-GC–MS analyses) a total of 130 metabolites (volatiles and non-volatiles) were identified. Most of them (117) were common to both cultivars; 95 were significantly different between both cultivars when comparing the whole set of data (ULO+DCA-CF), whereas 13 volatile compounds, identified via HS-SPME-GC–MS, were specific for either GS or RD. Multivariate analyses (PCA and PLS) of the whole dataset allowed to clearly discriminate between GS and RD samples. When storage condition was used as a categorical response variable, a lower percentage explained variance was obtained as this effect was overshadowed by the large effect of storage time. After 4 months of storage, RD underwent more pronounced metabolic compositional changes of the cortex, possibly associated with the evolution of ripening. Based on the accumulation pattern of pyruvate-derived metabolites (ethanol, acetaldehyde, lactate, alanine) it can be hypothesized that there are two main metabolic reconfiguration strategies in GS and RD to regenerate NAD+ and cope with energy crisis under hypoxia. GS showed more pronounced responses through changes in the nitrogen metabolism and limited induction of the ethanol fermentation while the latter was highly induced in RD under both ULO and DCA-CF. Marked differences were detected between the VOC profiles of the two cultivars regardless storage conditions. Ethyl esters and 2-methylbutyl derivatives appeared finely modulated by the oxygen level in GS and RD apples, respectively.

Treatment Effects of Ischemic Stroke by Berberine, Baicalin, and Jasminoidin from Huang-Lian-Jie-Du-Decoction (HLJDD) Explored by an Integrated Metabolomics Approach.

Berberine, baicalin, and jasminoidin were major active ingredients of Huang-Lian-Jie-Du-Decoction (HLJDD), a famous prescription of traditional Chinese medicine (TCM), which has been used for the treatment of ischemic stroke. The aim of the present study was to classify their roles in the treatment effects of ischemic stroke. A rat model of middle cerebral artery occlusion (MCAO) was constructed to mimic ischemic stroke and treatment effects of berberine, baicalin, and jasminoidin, and HLJDD was assessed by neurologic deficit scoring, infarct volume, histopathology, immunohistochemistry, biochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting. In addition, the 1H NMR metabolomics approach was used to assess the metabolic profiles, which combined with correlation network analysis successfully revealed metabolic disorders in ischemic stroke concerning the treatment of the three principal compounds from HLJDD for the first time. The combined results suggested that berberine, baicalin, and jasminoidin are responsible for the effectiveness of HLJDD on the treatment of ischemic stroke by amelioration of abnormal metabolism and regulation of oxidative stress, neuron autophagy, and inflammatory response. This integrated metabolomics approach showed its potential in understanding the function of complex formulae and clarifying the role of its components in the overall treatment effects.

Pyrazinamide-induced hepatotoxicity and gender differences in rats as revealed by a 1H NMR based metabolomics approach.

Pyrazinamide (PZA) is a well-known first line anti-tuberculosis drug used in combination with other drugs such as isoniazid and rifampicin. Unfortunately, PZA suffered from a high rate of hepatotoxicity and hyperuricemia, which has not been clearly elucidated, hindering its wide application for therapeutic purposes. The purpose of this investigation was to develop a model of rat sub-acute hepatotoxicity induced by PZA and to explore the affected metabolic pathways by a 1H NMR-based metabolomics approach complemented with histopathological analysis and clinical chemistry. Rats of both genders were administered with PZA by gavage at doses of 1.0 and 2.0 g kg-1 for 4 weeks. PZA decreased the weights of dosed rats and induced liver injury dose-dependently. The female rats were more sensitive to PZA induced damage. Orthogonal signal correction partial least-squares discriminant analysis (OSC-PLS-DA) of the NMR profiles of the rat liver and serum revealed that PZA produced a status of oxidative stress and disturbances in purine metabolism, energy metabolism and NAD+ metabolism in a gender-specific and dose-dependent manner. These findings could be helpful to clarify the mechanism of PZA-induced hepatotoxicity and hyperuricemia. This integrated metabolomics approach showcased its ability to characterize the global metabolic status of organisms, providing a powerful and feasible tool to probe drug induced toxicity or side effects.