Metabolic profiling studies on the toxicological effects of realgar in rats by (1)H NMR spectroscopy

Traditional mineral medicine realgar and Realgar-Indigo naturalis formula potentially exerted therapeutic effects by altering the gut microbiota

Introduction

Realgar has a long history ofuse in traditional medicines. However, the mechanism through which Realgar or Realgar-Indigo naturalis formula (RIF) exert therapeutic effects is only partially understood.

Methods

In this study, 60 feces and 60 ileum samples from rats administered with realgar or RIF were collected to examine the gut microbiota.

Results

The results showed that realgar and RIF influenced different microbiota in both feces and ileum. Compared with realgar, RIF at low dosage (0.1701 g/3 ml) significantly increased the microbiota diversity. LEfSe and random forest analyses showed that the bacterium Bacteroidales was significantly altered after RIF administration, and it was predicted that these microorganisms contribute to the inorganic arsenic metabolic process.

Discussion

Our results suggest that realgar and RIF may exert their therapeutic effects through influencing microbiota. The low dose of RIF had greater effects on increasing the diversity of microbiota, and Bacteroidales in feces might participate in the inorganic arsenic metabolic process to exert therapeutic effects for realgar.

Current Trends in Toxicity Assessment of Herbal Medicines: A Narrative Review

Even in modern times, the popularity level of medicinal plants and herbal medicines in therapy is still high. The World Health Organization estimates that 80% of the population in developing countries uses these types of remedies. Even though herbal medicine products are usually perceived as low risk, their potential health risks should be carefully assessed. Several factors can cause the toxicity of herbal medicine products: plant components or metabolites with a toxic potential, adulteration, environmental pollutants (heavy metals, pesticides), or contamination of microorganisms (toxigenic fungi). Their correct evaluation is essential for the patient’s safety. The toxicity assessment of herbal medicine combines in vitro and in vivo methods, but in the past decades, several new techniques emerged besides conventional methods. The use of omics has become a valuable research tool for prediction and toxicity evaluation, while DNA sequencing can be used successfully to detect contaminants and adulteration. The use of invertebrate models (Danio renio or Galleria mellonella) became popular due to the ethical issues associated with vertebrate models. The aim of the present article is to provide an overview of the current trends and methods used to investigate the toxic potential of herbal medicinal products and the challenges in this research field.

Compatibility of Niuhuang Jiedu Tablets Results in Attenuated Arsenic Bioaccumulation and Consequent Protection against Realgar-Induced Toxicity in Mice

Niuhuang Jiedu Tablets (NJT) is a popular over-the-counter traditional Chinese medicine (TCM) preparation. It is composed of realgar (As₂S₂) and seven other TCMs. The safety of NJT is of growing concern because arsenic (As) is carcinogenic to humans. The toxicity of realgar in vivo can mainly be attributed to the absorbed and accumulated As. This study investigated the correlation between the detoxification effects of the other TCMs in NJT on realgar and their influences on arsenic accumulation of realgar in mice. Histopathological examination, clinical biochemical test, and metabolic profiling analysis were used to evaluate the toxicity of realgar. The concentration of arsenic in mice whole blood as the hazard indicator was determined by inductively coupled plasma mass spectrometry (ICP-MS). The compatibility of NJT could decrease arsenic bioaccumulation of realgar in mice whole blood and consequently reduce the toxicity of realgar, which could be considered as one detoxification mechanism to realgar in NJT. The combination of Rhei Radix et Rhizoma, Scutellariae Radix, Platycodonis Radix, and Glycyrrhizae Radix et Rhizoma exhibited almost the same effects as NJT in regulating the serum biochemical parameters and metabolic profiles disturbed by realgar and in reducing arsenic accumulation of realgar in mice whole blood.

Acute and subacute toxicity evaluation of Houttuynia cordata ethanol extract and plasma metabolic profiling analysis in both male and female rats

Houttuynia cordata has been used as a traditional medicine for more than 1500 years. It has aroused wide public concern about its safety in the past few years, for it contains various aristolactams. However, the safety of H. cordata extract remains unclear. In the present study, single dose (2000 mg/kg) and subacute (250, 500, and 1000 mg/kg/day for 28 days) oral toxicity studies of the 95% ethanol extract of H. cordata (HCE) were performed in both male and female Sprague-Dawley (SD) rats. Hematological, biochemical, histopathological parameters, and plasma metabolic profiling were assessed. The single-dose toxicity of HCE was more than 2000 mg/kg. The subacute toxicity results showed that no significant adverse effect of HCE was observed at 250 mg/kg/day. However, five rats died in 500 and 1000 mg/kg/day groups and exhibited toxicities to liver and kidney. Plasma metabolic profiling analysis suggested that a number of metabolic disturbances were induced by oral administration of HCE, focusing on energy metabolism, amino acid metabolism, and lipids metabolism. Moreover, it appeared that male rats were more susceptible to the toxic effects of HCE than female rats. Therefore, in this preliminary study, oral administration of HCE 250 mg/kg/day can be regarded as the no observed adverse effect level in rats over 28 days. However, long-term use of HCE with large doses exhibited some hepatotoxicity and nephrotoxicity in rats.

Association between body mass index and arsenic methylation in three studies of Bangladeshi adults and adolescents

BACKGROUND

Water-borne arsenic (As) exposure is a global health problem. Once ingested, inorganic As (iAs) is methylated to mono-methyl (MMA) and dimethyl (DMA) arsenicals via one-carbon metabolism (OCM). People with higher relative percentage of MMA (MMA%) in urine (inefficient As methylation), have been shown to have a higher risk of cardiovascular disease and several cancers but appear to have a lower risk of diabetes and obesity in populations from the US, Mexico, and Taiwan. It is unknown if this opposite pattern with obesity is present in Bangladesh, a country with lower adiposity and higher As exposure in drinking water.

OBJECTIVE

To characterize the association between body mass index (BMI) and As methylation in Bangladeshi adults and adolescents participating in the Folic Acid and Creatine Trial (FACT); Folate and Oxidative Stress (FOX) study; and Metals, Arsenic, and Nutrition in Adolescents Study (MANAS).

METHODS

Arsenic species (iAs, MMA, DMA) were measured in urine and blood. Height and weight were measured to calculate BMI. The associations between concurrent BMI with urine and blood As species were analyzed using linear regression models, adjusting for nutrients involved in OCM such as choline. In FACT, we also evaluated the prospective association between weight change and As species.

RESULTS

Mean BMIs were 19.2/20.4, 19.8/21.0, and 17.7/18.7 kg/m2 in males/females in FACT, FOX, and MANAS, respectively. BMI was associated with As species in female but not in male participants. In females, after adjustment for total urine As, age, and plasma folate, the adjusted mean differences (95% confidence) in urinary MMA% and DMA% for a 5 kg/m2 difference in BMI were -1.21 (-1.96, -0.45) and 2.47 (1.13, 3.81), respectively in FACT, -0.66 (-1.56, 0.25) and 1.43 (-0.23, 3.09) in FOX, and -0.59 (-1.19, 0.02) and 1.58 (-0.15, 3.30) in MANAS. The associations were attenuated after adjustment for choline. Similar associations were observed with blood As species. In FACT, a 1-kg of weight increase over 2 to 10 (mean 5.4) years in males/females was prospectively associated with mean DMA% that was 0.16%/0.19% higher.

DISCUSSION

BMI was negatively associated with MMA% and positively associated with %DMA in females but not males in Bangladesh; associations were attenuated after plasma choline adjustment. These findings may be related to the role of body fat on estrogen levels that can influence one-carbon metabolism, e.g. by increasing choline synthesis. Research is needed to determine whether the associations between BMI and As species are causal and their influence on As-related health outcomes.

The Herbal Constituents in An-Gong-Niu-Huang Wan (AGNH) Protect against Cinnabar- and Realgar-Induced Hepatorenal Toxicity and Accumulations of Mercury and Arsenic in Mice

An-Gong-Niu-Huang Wan (AGNH) has been a well-known cinnabar- and realgar-containing compound recipe for cerebral diseases. Unfortunately, its clinical practice is often restrained by the specific hepatorenal toxicity of cinnabar and realgar (C + R). In previous research studies, we have found that the antioxidative and anti-inflammatory effects of its herbal constituents could mitigate the risks from the toxicity. The underlying detoxification mechanisms are still unsolved. The present study investigated the protective effects of AGNH's herbal constituents on hepatorenal injury induced by C + R. For the mice treated with C + R, the increased expression levels of sensitive biomarkers of metal exposure and hepatorenal toxicity, including metallothionein (MT) in both hepatorenal tissues and kidney induced molecule-1 (KIM-1) in the kidney, were simultaneously reduced when C + R coadministered with other herbal medicines. In addition, the contents of trivalent As (As^III), pentavalent As (As^v), and mercury (Hg) in hepatorenal tissues of mice were also significantly reduced benefiting from the herbal constituents in AGNH. Further mechanism studies showed that the herbal constituents in AGNH could downregulate the expressions of uptake transporters (AQP9 and OAT1) and upregulate the expressions of efflux transporters (P-gp, MRP2, and MRP4) in mice intoxicated by C + R. Our results suggested that AGNH's herbal constituents protect the body against C + R-induced hepatorenal toxicity and accumulations of Hg and As, which could be associated with the reestablishment of heavy metal homeostasis and the detoxification system.

Liver metabonomics study on the protective effect of glycyrrhetinic acid against realgar-induced liver injury

Glycyrrhetinic acid (GA) is the bioactive ingredient in Glycyrrhizae Radix et Rhizoma. Our previous study has reported that GA has protective effect on realgar-induced hepatotoxicity. However, the details of the hepatoprotective mechanisms of GA on realgar-induced liver injury remain to be elucidated. In the study, mice were divided into control, GA-control, realgar, and co-treated groups. Their liver tissues were used for metabonomics study by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) method. The results illustrate that GA significantly ameliorate the liver injury and metabolic perturbations caused by realgar. Some metabolites, such as phenylalanine, pyroglutamic acid (PGA), proline, carnitine, nicotinamide, choline, lysophosphatidylcholine (LPC) 16 : 0 and LPC 18 : 2 were found responsible for the hepatoprotective effect of GA. These metabolites are associated with the methylation metabolism of arsenic, cell membrane structure, energy metabolism and oxidative stress. From the results of this study, we infer that the potential hepatoprotective mechanism of GA on realgar-induced liver injury may be associated with reducing arsenic accumulation and its methylation metabolism in the liver, promoting the conjugation of arsenic and GSH to play detoxification effect, and ameliorating the liver metabolic perturbations caused by realgar.

NMR-Based Metabonomic Study Reveals Intervention Effects of Polydatin on Potassium Oxonate-Induced Hyperuricemia in Rats

Previous studies have disclosed the antihyperuricemic effect of polydatin, a natural precursor of resveratrol; however, the mechanisms of action still remain elusive. The present study was undertaken to evaluate the therapeutic effects and the underlying mechanisms of polydatin on potassium oxonate-induced hyperuricemia in rats through metabonomic technology from a holistic view. Nuclear magnetic resonance (NMR) spectroscopy was applied to capture the metabolic changes in sera and urine collected from rats induced by hyperuricemia and polydatin treatment. With multivariate data analysis, significant metabolic perturbations were observed in hyperuricemic rats compared with the healthy controls. A total of eleven and six metabolites were identified as differential metabolites related to hyperuricemia in serum and urine of rats, respectively. The proposed pathways primarily included branched-chain amino acid (BCAA) metabolism, glycolysis, the tricarboxylic acid cycle, synthesis and degradation of ketone bodies, purine metabolism, and intestinal microflora metabolism. Additionally, some metabolites indicated the risk of renal injury induced by hyperuricemia. Polydatin significantly lowered the levels of serum uric acid, creatinine, and blood urea nitrogen and alleviated the abnormal metabolic status in hyperuricemic rats by partially restoring the balance of the perturbed metabolic pathways. Our findings shed light on the understanding of the pathophysiological process of hyperuricemia and provided a reference for revealing the metabolic mechanism produced by polydatin in the treatment of hyperuricemia.

Target lipidomics approach to reveal the resolution of inflammation induced by Chinese medicine combination in Liu-Shen-Wan against realgar overexposure to rats

ETHNOPHARMACOLOGICAL RELEVANCE

Liu-Shen-Wan (LSW) is one of the popular over-the-counter drugs in Asia, which contains realgar (As₄S₄), used for the treatment of upper respiratory tract inflammation and skin infections. However, the safety and potential risk of this arsenic remain unknown.

AIM OF THE STUDY

The aim of this study was to determine total arsenic in tissue and investigate effects of regular dose and overdose LSW exposure on rat liver.

MATERIALS AND METHODS

We used a target lipidomics approach to quantify inflammatory eicosanoids and employed ICP-MS to determine total arsenic in tissue.

RESULTS

The results showed that oral administration of 8 and 40 mg/kg LSW (1 and 5 fold human-equivalent dose) induced light changes of liver lipidomic profile in rats, which was associated with anti-inflammatory function of LSW. In our recent report, we observed that 41 and 134 mg/kg realgar (40 and 132 fold human-equivalent dose) stimulated rat liver inflammation through up-regulation of pro-inflammatory LOX-derived, CYP-derived HETEs and COX-derived PGs. However, we found that LSW in the form of drug combination, containing 41 and 134 mg/kg realger, could not stimulate these similar inflammatory responses in rats, although the liver total arsenic levels of the realger and LSW groups were same.

CONCLUSION

The downregulation of pro-inflammatory response showed that the LSW containing realger is safer than realger alone administrated to rats. These results suggested that Chinese medicines combination could reduce realgar-derived arsenic toxicity in rats.

Novel and selective inactivators of Triosephosphate isomerase with anti-trematode activity

Trematode infections such as schistosomiasis and fascioliasis cause significant morbidity in an estimated 250 million people worldwide and the associated agricultural losses are estimated at more than US$ 6 billion per year. Current chemotherapy is limited. Triosephosphate isomerase (TIM), an enzyme of the glycolytic pathway, has emerged as a useful drug target in many parasites, including Fasciola hepatica TIM (FhTIM). We identified 21 novel compounds that selectively inhibit this enzyme. Using microscale thermophoresis we explored the interaction between target and compounds and identified a potent interaction between the sulfonyl-1,2,4-thiadiazole (compound 187) and FhTIM, which showed an IC₅₀ of 5 µM and a K_d of 66 nM. In only 4 hours, this compound killed the juvenile form of F. hepatica with an IC₅₀ of 3 µM, better than the reference drug triclabendazole (TCZ). Interestingly, we discovered in vitro inhibition of FhTIM by TCZ, with an IC₅₀ of 7 µM suggesting a previously uncharacterized role of FhTIM in the mechanism of action of this drug. Compound 187 was also active against various developmental stages of Schistosoma mansoni. The low toxicity in vitro in different cell types and lack of acute toxicity in mice was demonstrated for this compound, as was demonstrated the efficacy of 187in vivo in F. hepatica infected mice. Finally, we obtained the first crystal structure of FhTIM at 1.9 Å resolution which allows us using docking to suggest a mechanism of interaction between compound 187 and TIM. In conclusion, we describe a promising drug candidate to control neglected trematode infections in human and animal health.

Metabolomics coupled with SystemsDock reveal the protective effect and the potential active components of Naozhenning granule against traumatic brain injury

ETHNOPHARMACOLOGICAL RELEVANCE

Naozhenning granule (NZN), a widely traditional Chinese medicine (TCM) prescription with a long history of clinical, which is mainly used in the treatment of concussion, cerebral post-traumatic syndrome, consists of Di Huang (Radix of Rehmannia glutinosa (Gaertn.) DC.), Dang Gui (Radix of Angelica sinensis (Oliv.) Diels), Chen Pi (Pericarpium of Citrus reticulata Blanco), Dan shen (Radix of Salvia Miltiorrhiza Bunge.), Di Long (Pheretima aspergillum (E. Perrier)), Mu Dan Pi (Cortex of Paeonia suffruticosa Andrews), Suan Zao Ren (Semen of Ziziphus jujuba Mill.), Chuan Xiong (Rhizoma of Ligusticum striatum DC.), Zhu Ru (Phyllostachys nigra (Lodd. Ex Lindl.) Munro), Bai Zi Ren (Semen of Platycladus orientalis (L.) Franco) and Fu Ling (sclerotium of Poria cocos (Schw.)Wolf).

AIM OF THE STUDY

This study aimed to unravel the mechanism and material basis of NZN against traumatic brain injury.

MATERIALS AND METHODS

In this study, a ¹H nuclear magnetic resonance (NMR) based metabolomic approach combined with systemsDock was employed to study the protective effect of NZN against traumatic brain injury using a cerebral concussion rat model. The morris water maze test and biochemical indexes were used to evaluate the efficacy of NZN.

RESULTS

The results of morris water maze test suggested NZN can improve the spatial learning and memory of model rats, and the superoxide dismutas (SOD) and malonyldialdehyde (MDA) level indicated that the effect of NZN was related with the regulation of oxidative stress. Multivariate analysis revealed that the effect of NZN was related with regulation of 18 brain metabolites, and the corresponding metabolic pathways were further revealed by MetPA analysis. 13 serum absorbed components were found to hit the targets both related with the metabolic regulation and cerebral trauma through systemsDock-aided molecular docking experiments, and these compounds might be served as the active compounds in NZN against cerebral trauma.

CONCLUSION

¹H-NMR based metabolomics and molecular docking provided the insights for the synergistic mechanisms and the potential active compounds of NZN in treating cerebral trauma. However, the bioactive compounds and their synergistic effect need to be further validated.

Arsenic Bioaccessibility of Realgar Influenced by the Other Traditional Chinese Medicines in Niuhuang Jiedu Tablet and the Roles of Gut Microbiota

Niuhuang Jiedu tablet (NJT), a realgar (As2S2) containing Traditional Chinese Medicine (TCM), is a well-known formula. The safety of NJT is of growing concern since arsenic (As) is considered as one of the most toxic elements. NJT was demonstrated to be safer than realgar by our previous experiments and some other studies. The toxicity of realgar has been shown to be related to the amount of soluble or bioaccessible arsenic. In this study, the influences of the other TCMs in NJT on the bioaccessibility of arsenic from realgar, and the roles of gut microbiota during this process were investigated in vitro. Results showed that Dahuang (Rhei Radix et Rhizoma), Huangqin (Scutellariae Radix), Jiegeng (Platycodonis Radix), and Gancao (Glycyrrhizae Radix et Rhizoma) could significantly reduce the bioaccessibility of arsenic from realgar in artificial gastrointestinal fluids. Gut microbiota played an important role in decreasing the bioaccessibility of realgar because it was demonstrated to be able to absorb the soluble arsenic from realgar in the incubation medium. Dahuang, Huangqin, and Jiegeng could modulate the gut microbiota to enhance its arsenic absorption activity.

Urinary 1H NMR metabolomics profile of Italian citizens exposed to background levels of arsenic: a (pre)cautionary tale

Objectives: Arsenic is a toxic metal ubiquitous in the environment and in daily life items. Long-term arsenic exposure is associated with severe adverse health effects involving various target organs. It would be useful to investigate the existence of metabolic alterations associated with lifestyle and/or with the environment. For this purpose, we studied the correlation between urinary arsenic levels and urinary proton nuclear magnetic resonance spectroscopy (¹H NMR) metabolomics profiles in a non-occupationally nor environmentally arsenic exposed general population.Methods: Urine samples were collected from 86 healthy subjects. Total and non-alimentary urinary arsenic (U-naAs) levels, namely the sum of arsenite, arsenate, monomethylarsonate and dimethylarsinate, were measured and ¹H NMR analysis was performed. Orthogonal Projection to Latent Structures was applied to explore the correlation between the metabolomics profiles and U-naAs levels.Results: Despite the extremely low U-naAs levels (mean value = 6.13 ± 3.17 µg/g creatinine) of our studied population a urinary metabolomics profile related to arsenic was identified.Conclusion: The identified profile could represent a fingerprint of early arsenic biological effect and could be used in further studies as an indicator of susceptibility, also in subjects exposed to a low arsenic dose, with implications in occupational health, toxicology, and public health.

Integrated Systems Pharmacology, Urinary Metabonomics, and Quantitative Real-Time PCR Analysis to Uncover Targets and Metabolic Pathways of the You-Gui Pill in Treating Kidney-Yang Deficiency Syndrome

Kidney-yang deficiency syndrome (KYDS) is a metabolic disease caused by a neuro-endocrine disorder. The You-gui pill (YGP) is a classic traditional Chinese medicine (TCM) formula for the treatment of KYDS and has been widely used to warm and recuperate KYDS clinically for hundreds of years in China. However, it is unknown whetherthe corresponding targets and metabolic pathways can also be found via using metabonomics based on one platform (e.g., 1H NMR) to study different biological samples of KYDS. At the same time, relevant reports on further molecular verification (e.g., RT-qPCR analysis) of these targets associated with biomarkers and metabolic pathways have not yet, to our knowledge, been seen in KYDS's research. In the present study, a comprehensive strategy integrating systems pharmacology and 1H NMR-based urinary metabonomics analysis was proposed to identify the target proteins and metabolic pathways that YGP acts on KYDS. Thereafter, further validation of target proteins in kidney tissue was performed through quantitative real-time PCR analysis (RT-qPCR). Furthermore, biochemical parameters and histopathological analysis were studied. As a result, seven target proteins (L-serine dehydratase; phosphoenolpyruvate carboxykinase; spermidine synthase; tyrosyl-tRNA synthetase, glutamine synthetase; 3-hydroxyacyl-CoA dehydrogenase; glycine amidinotransferase) in YGP were discovered to play a therapeutic role in KYDS via affecting eight metabolic pathways (glycine, serine and threonine metabolism; butanoate metabolism; TCA cycle, etc.). Importantly, three target proteins (i.e., 3-hydroxyacyl-CoA dehydrogenase; glutamine synthetase; and glycine amidinotransferase) and two metabolic pathways (butanoate metabolism and dicarboxylate metabolism) related to KYDS, to our knowledge, had been newly discovered in our study. The mechanism of action mainly involved energy metabolism, oxidative stress, ammonia metabolism, amino acid metabolism, and fatty acid metabolism. In short, our study demonstrated that targets and metabolic pathways for the treatment of KYDS by YGP can be effectively found via combining with systems pharmacology and urinary metabonomics. In addition to this, common and specific targets and metabolic pathways of KYDS treated by YGP can be found effectively by integration with the analysis of different biological samples (e.g., serum, urine, feces, and tissue). It is; therefore, important that this laid the foundation for deeper mechanism research and drug-targeted therapy of KYDS in future.

A NMR-Based Metabonomics Approach to Determine Protective Effect of a Combination of Multiple Components Derived from Naodesheng on Ischemic Stroke Rats

Naodesheng (NDS) is a widely used traditional Chinese medicine (TCM) prescription for the treatment of ischemic stroke. A combination of 10 components is derived from NDS. They are: Notoginsenoside R1, ginsenoside Rg1, ginsenoside b1, ginsenoside Rd, hydroxysafflor yellow A, senkyunolide I, puerarin, daidzein, vitexin, and ferulic acid. This study aimed to investigate the protective effect of the ten-component combination derived from NDS (TCNDS) on ischemic stroke rats with a middle cerebral artery occlusion (MCAO) model by integrating an NMR-based metabonomics approach with biochemical assessment. Our results showed that TCNDS could improve neurobehavioral function, decrease the cerebral infarct area, and ameliorate pathological features in MCAO model rats. In addition, TCNDS was found to decrease plasma lactate dehydrogenase (LDH) and malondialdehyde (MDA) production and increase plasma superoxide dismutase (SOD) production. Furthermore, ¹H-NMR metabonomic analysis indicated that TCNDS could regulate the disturbed metabolites in the plasma, urine, and brain tissue of MCAO rats, and the possible mechanisms were involved oxidative stress, energy metabolism, lipid metabolism, amino acid metabolism, and inflammation. Correlation analysis were then performed to further confirm the metabolites involved in oxidative stress. Correlation analysis showed that six plasma metabolites had high correlations with plasma LDH, MDA, and SOD. This study provides evidence that an NMR-based metabonomics approach integrated with biochemical assessment can help to better understand the underlying mechanisms as well as the holistic effect of multiple compounds from TCM.

Fatal acute arsenic poisoning by external use of realgar: Case report and 30 years literature retrospective study in China

Realgar (arsenic sulfide) is widely used in combination with other herbs as Chinese patent medicine to treat a variety of diseases in China. As a mineral arsenic, its mild toxicity was also well known. Longtime over-dose usage or wrongly oral intake of realgar can cause chronic arsenic poisoning and/or death, but acute fatal arsenic poisoning resulted from short-term dermal use of realgar-containing medicine was very rare. Here, we present the case of a 35-year-old Chinese man, who was diagnosed with severe psoriasis and died of fatal acute arsenic poisoning after he applied a local folk prescription ointment containing mainly the realgar to the affected skin for about 4 days. The autopsy showed multiple punctate hemorrhages over the limbs, pleural effusion, edematous lungs with consolidation, mild myocardial hypertrophy and normal-looking kidneys. The histopathological examination of renal tissue showed severe degeneration, necrosis and desquamation of renal tubular epithelial cells, presence of protein cast and a widened edematous interstitium with interstitial fibrosis. The presence of arsenic in large amount in the ointment (about 6%), in blood (1.76 μg/mL), and in skin (4.71 μg/g), were confirmed analytically. We also provide the clinical records of the deceased and briefly reviewed 7 similar cases in literature (6 in Chinese and 1 in English) in the past 30 years in China.

A comparative study of intratracheal and aerosolization instillations of bleomycin inducing experimental lung fibrosis in rat

We aimed to investigate in the present work, using metabonomics approaches, the scalability of lung fibrosis-biomarkers, in bleomycin (BLM) model of pulmonary fibrosis in rats. Sixty male Wistar rats, weighing 250 ± 10 g, were randomly divided into three groups: a negative control group receiving normal saline treatment (G₁), an intratracheal BLM instilled group (G₂), and an aerosol BLM instilled group (G₃). Rats were investigated at various times after BLM instillation. Metabolic changes observed in different biofluids have been integrated into the results of the histological examination (increase in inflammation, fibrosis score, and TGF-β immunostaining) which provide a novel pathway of biomarkers in pulmonary fibrosis. These two BLM-models showed an efficacy in the production of pulmonary fibrosis in rats, accompanied by an oxidative stress in lung tissue as assessed by the increase of lipid peroxidation and the depletion in the level of antioxidant enzymes such as superoxide dismutase and catalase. The aerosol model was more advantageous showing fibrotic foci occupying the majority of the lung in contrast to intratracheal instillation characterized by a non-homogeneous distribution of the fibroblastic foci.

UPLC/Q-TOFMS-Based Metabolomics Approach to Reveal the Protective Role of Other Herbs in An-Gong-Niu-Huang Wan Against the Hepatorenal Toxicity of Cinnabar and Realgar

An-Gong-Niu-Huang Wan (AGNH) is a well-known traditional Chinese medicine (TCM) recipe containing cinnabar (HgS) and realgar (As₂S₂). However, the application of AGNH is limited by the hepato- and nephrotoxicity of cinnabar and realgar. It should be noted that cinnabar and realgar in AGNH are not used alone, but rather combined with other herbs as formula to use. In this study, the protective effects and mechanisms of the other herbs in AGNH against the hepatorenal toxicity induced by cinnabar and realgar were investigated. The combination use of the other herbs in AGNH alleviated inflammatory cell infiltration and damage in the liver and kidney and restored the disturbed serum metabolic profile induced by cinnabar and realgar insults. By UPLC/Q-TOFMS combined with pattern recognition approaches, we identified 41 endogenous metabolites in the sera of mice that were related to the hepatorenal toxicity of cinnabar and realgar, 36 of which were restored to normal levels when various kinds of herbs were combined as compound recipe. These metabolites function as modulators in inflammation-associated glycerophospholipid, arachidonic acid, linoleic acid, sphingolipid, and ether lipid metabolic pathways. Notably, lysophosphatidylcholines (LysoPCs) were the most elevated among all of the metabolites detected after cinnabar and realgar treatment, while these LysoPCs did not show overt differences between the AGNH and saline control groups, which was associated with relatively unaffected or even up-regulated expression of lysophosphatidylcholine acyltransferase 1 (LPCAT1) and autotaxin (ATX). These findings indicated that other herbs in AGNH could have a protective effect against cinnabar- and realgar-induced hepatic and renal damage via modulating the disordered homeostasis of the glycerophospholipid, arachidonic acid, linoleic acid, ether lipid, and sphingolipid metabolism.

Combination of LC/MS and GC/MS based metabolomics to study the hepatotoxic effect of realgar nanoparticles in rats

Realgar nanoparticles (NPs) are increasingly used as therapeutic agents for their enhanced anti-proliferation effect and cytotoxicity on cancer cells. However, the alteration of particle size may enhance biological reactivity as well as toxicity. A LC/MS and GC/MS based metabolomics approach was employed to explore the mechanism of realgar NPs-induced hepatotoxicity and identify potential biomarkers. Male Sprague-Dawley rats were administrated intragastrically with realgar or realgar NPs at a dose of 1.0 g·kg^-1·d^-1 for 28 days and toxic effects of realgar NPs on liver tissues were examined by biochemical indicator analysis and histopathologic examination. Increased levels of serum enzymes and high hepatic steatosis were discovered in the realgar NPs treated group. Multivariate data analysis revealed that rats with realgar NPs-induced hepatotoxicity could be distinctively differentiated from the animals in the control and realgar treated groups. In addition, 21 and 32 endogenous metabolites were apparently changed in the serum and live extracts, respectively. Realgar NPs might induce free fatty acid and triglyceride accumulation, resulting in hepatotoxicity. In conclusion, the present study represents the first comprehensive LC/MS- and GC/MS-based metabolomics analysis of realgar NPs-induced hepatotoxicity, which may help further research of nanotoxicity.

Metabolic Profiling Analysis of the Alleviation Effect of the Fractions of Niuhuang Jiedu Tablet on Realgar Induced Toxicity in Rats

Niuhuang Jiedu Tablet (NJT) is a classical formula in treating acute tonsillitis, pharyngitis, and so on. In the formula, significant level of Realgar as a potentially toxic element is contained. Our previous experiments revealed that it was less toxic for combined Realgar in NJT. However, the active fraction of this prescription with toxicity alleviation effect on Realgar was still obscure. NJT was divided into five different polar fractions (NJT-PET, NJT-25, NJT-50, NJT-75, and NJT-95), and we explored the toxicity alleviation effect on Realgar. Based on 1H NMR spectra of urine and serum from rats, PCA and PLS-DA were performed to identify different metabolic profiles. Liver and kidney histopathology examinations and serum clinical chemistry analysis were also performed. With pattern recognition analysis of metabolites in urine and serum, Realgar group showed a clear separation from control group, while the metabolic profiles of NJT-PET, NJT-25, NJT-50, and NJT-95 groups were similar to Realgar group, and the metabolic profiles of NJT and NJT-75 groups were very close to control group. Statistics results were confirmed by the histopathological examination and biochemical assay. The present work indicated that 75% EtOH fraction of NJT was the most valid fraction with the toxicity alleviation effect on Realgar.

Exploring the biomarkers and therapeutic mechanism of kidney-yang deficiency syndrome treated by You-gui pill using systems pharmacology and serum metabonomics

In this study, systems pharmacology was used to predict the molecular targets of You-gui pill (YGP) and explore the therapeutic mechanism of Kidney-Yang Deficiency Syndrome (KYDS) treated with YGP. On the basis of this, serum samples from control group, KYDS model group and YGP group rats were studied using 1H NMR to verify the results of systems pharmacology from the level of metabonomics. Simultaneously, 1H NMR spectra of serum samples were obtained and statistically assessed using pattern recognition analysis. Biochemical analyses of serums were performed via radioimmunoassays. Furthermore, histopathological studies were conducted on the pituitary, adrenal, and thyroid glands, and testicles of the control, KYDS and YGP rats. Using systems pharmacology to analyze the active components of YGP, 61 active compounds were finally found. These compounds were likely to have an effect on 3177 target proteins and involve 234 pathways. Using metabonomics to analyze serum from KYDS rats treated with YGP, 22 endogenous biomarkers were found. These biomarkers were mainly involved in 10 metabolic pathways. Combining systems pharmacology and metabonomics, we found that the regulation of KYDS was primarily associated with 19 active compounds of 5 Chinese herbal medicines in YGP. These active compounds mainly had an effect on 8 target proteins, including phosphoenolpyruvate carboxykinase, betaine-homocysteine s-methyltransferase 1, alcohol dehydrogenase 1C, etc. These target proteins were primarily involved in 6 overlapping pathways, namely aminoacyl-tRNA biosynthesis, glycolysis/gluconeogenesis, glycine, serine and threonine metabolism, valine, leucine and isoleucine biosynthesis, arginine and proline metabolism, and pyruvate metabolism. In addition, there were 4 non-overlapping pathways, respectively alanine, aspartate and glutamate metabolism, d-glutamine and d-glutamate metabolism, ubiquinone and other terpenoid-quinone biosynthesis, and galactose metabolism. In summary, the therapeutic effects of YGP on KYDS were mainly associated with neuroendocrine regulation, energy metabolism, amino acid metabolism, inflammatory responses, apoptosis, oxidative stress and intestinal flora metabolism. What's more, we also found that YGP possessed the potential to protect liver and kidney function. Our study demonstrated that systems pharmacology and metabonomics methods were novel strategies for the exploration of the mechanisms of KYDS and TCM formulas.

1H NMR-Based Metabolomics Study of the Toxicological Effects in Rats Induced by "Renqing Mangjue" Pill, a Traditional Tibetan Medicine

“RenqingMangjue” pill (RMP), as an effective prescription of Traditional Tibetan Medicine (TTM), has been widely used in treating digestive diseases and ulcerative colitis for over a thousand years. In certain classical Tibetan Medicine, heavy metal may add as an active ingredient, but it may cause contamination unintentionally in some cases. Therefore, the toxicity and adverse effects of TTM became to draw public attention. In this study, 48 male Wistar rats were orally administrated with different dosages of RMP once a day for 15 consecutive days, then half of the rats were euthanized on the 15th day and the remaining were euthanized on the 30th day. Plasma, kidney and liver samples were acquired to ¹H NMR metabolomics analysis. Histopathology and ICP-MS were applied to support the metabolomics findings. The metabolic signature of plasma from RMP-administrated rats exhibited increasing levels of glucose, betaine, and creatine, together with decreasing levels of lipids, 3-hydroxybutate, pyruvate, citrate, valine, leucine, isoleucine, glutamate, and glutamine. The metabolomics analysis results of liver showed that after RMP administration, the concentrations of valine, leucine, proline, tyrosine, and tryptophan elevated, while glucose, sarcosine and 3-hydroxybutyrate decreased. The levels of metabolites in kidney, such as, leucine, valine, isoleucine and tyrosine, were increased, while taurine, glutamate, and glutamine decreased. The study provides several potential biomarkers for the toxicity mechanism research of RMP and shows that RMP may cause injury in kidney and liver and disturbance of several pathways, such as energy metabolism, oxidative stress, glucose and amino acids metabolism.

1H NMR and MVA metabolomic profiles of urines from piglets fed with boluses contaminated with a mixture of five mycotoxins

Metabolic profile of urine from piglets administered with single boluses contaminated with mycotoxin mixture (deoxynivalenol, aflatoxin B1, fumonisin B1, zearalenone, and ochratoxin A) were studied by 1H NMR spectroscopy and chemometrics (PCA, PLS-DA, and OPLS-DA). The mycotoxin levels were close to the established maximum and guidance levels for animal feed (2003/100/EC and 2006/576/EC). Urine samples were obtained from four groups of four piglets before (control, C) or within 24 h (treated, T) after receiving a contaminated boluses with increasing doses of mycotoxins (boluses 1-4). For the two highest dose groups, the urines were collected also after one week of wash out (W). For the two lowest doses groups no significant differences between the C and T samples were observed. By contrast, for the two highest doses groups the T urines separated from the controls for a higher relative content of creatinine, p-cresol glucuronide and phenyl acetyl glycine and lower concentration of betaine and TMAO. Interestingly, a similar profile was found for both W and T urines suggesting, at least for the highest doses used, serious alteration after a single bolus of mycotoxin mixture.

Metabolomic Analysis of N-acetylcysteine Protection of Injury from Gadolinium-DTPA Contrast Agent in Rats with Chronic Renal Failure

Gadolinium-based contrast agents (GBCAs) are frequently used to enhance the diagnostic efficacy of magnetic resonance imaging. On the other hand, the association between GBCA administration in patients with advanced renal disease and nephrogenic systemic fibrosis (NSF) was also noted. NSF is a systemic disorder characterized by widespread tissue fibrosis that may lead to death. N-acetylcysteine (NAC) protects rats from injury induced by gadolinium-based contrast agents, but the underlying mechanisms remain unclear. In this study, a nuclear magnetic resonance-based metabolomic approach was used to systematically investigate the protective effects of NAC on Gd-DTPA-induced injury. Thirty-two male Sprague-Dawley rats were given adenine (200 mg·kg^-1 body weight) by oral gavage once a day for 3 weeks to induce chronic renal failure (CRF). NAC (600 mg/L in drinking water for 9 days) pretreatment was initiated 2 days before Gd-DTPA injection (a single tail vein injection, 2 mmol/kg body weight). Serum and liver samples were collected on day 7 after Gd-DTPA injection. By study design, the serum and hepatic metabolic changes of rats were measured in four groups of eight each: CRF, CRF-Gd, CRF-Gd-NAC, and CRF-NAC. Gd-DTPA administration to rats with CRF resulted in disturbances of several metabolic pathways, including glucose, lipid, glutamate, choline, gut microbiota, one-carbon, and purine metabolism. NAC pretreatment reversed the abundance changes of high-density lipoprotein, low-density lipoprotein, very low-density lipoprotein, glutamate, glutamine, oxidized glutathione, choline, phosphocholine, glycerophosphocholine, trimethylamine, and trimethylamine-N-oxide induced by Gd-DTPA. It is noteworthy, however, that the ameliorating effects of NAC on the disturbance of glutamate, choline, and gut microbiota metabolism may be specific to Gd-DTPA. In all, these findings could be potentially useful to decipher the underlying mechanisms of NAC protective effects from the injury induced by gadolinium-based contrast agents.

Plasma metabolomics study of the hepatoprotective effect of glycyrrhetinic acid on realgar-induced sub-chronic hepatotoxicity in mice via 1H NMR analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Realgar, a type of mineral drug that contains arsenic, is concurrently used with Glycyrrhizae Radx et Rhizoma to reduce its toxicity in many Chinese herbal formulations. Glycyrrhetinic acid (GA) is the bioactive ingredient in Glycyrrhizae Radx et Rhizoma. In this study, the protective effects of GA on realgar-induced hepatotoxicity was investigated using ¹H nuclear magnetic resonance (¹H NMR)-based metabolomic approaches.

MATERIALS AND METHODS

Mice were divided into control, GA, realgar, and GA and realgar co-administration groups. Their plasma samples were used for a metabolomics study.

RESULTS

GA can protect the mice against realgar-induced hepatotoxicity to some extent by relieving alterations in the clinical biochemical parameters and the damage to hepatocytes. Metabolic profiling via principal components analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) indicated that the metabolic perturbation caused by realgar was reduced by GA. Six metabolites, including 3-hydroxybutyrate (3-HB), very low density/low density lipoprotein (VLDL/LDL), N-acetylglycoprotein (NAc), lactate, choline and D-glucose, were considered as potential biomarkers that are involved in the toxicity reduction effect of GA on realgar-induced hepatotoxicity. The correlation analysis showed that these potential biomarkers were all positively correlated with ALT and AST activities (correlation coefficient > 0.5). Lipid and energy metabolism pathways were found to be primarily associated with the hepatoprotective effect of GA.

CONCLUSIONS

GA has an effective protection function by regulating the lipid and energy metabolism to liver injuries that are induced by realgar.

Accumulation of Arsenic Speciation and In Vivo Toxicity Following Oral Administration of a Chinese Patent Medicine Xiao-Er-Zhi-Bao-Wan in Rats

Realgar-containing traditional Chinese medicines such as Xiao-Er-Zhi-Bao-Wan (XEZBW), have been widely used for thousands of years. However, events associated with arsenic-induced ailments have increasingly become a public concern. To address the toxicity of XEZBW, we studied the histopathology and blood biochemistry of rats exposed to XEZBW using technology like high-performance liquid chromatography-inductively coupled mass spectrometry to determine arsenic speciation. Our results demonstrated that dimethylarsinic acid (DMA) increased from 18.57 ± 7.45 to 22.74 ± 7.45 ng/g in rat kidney after oral administration for 7 and 14 days, which was 10-fold higher than the levels observed in controls. Trivalent arsenite As(III) showed a large increase on day 7 (26.99 ± 1.98 ng/g), followed by a slight decrease on day 14 (13.67 ± 6.48 ng/g). Total arsenic levels on day 7 (185.52 ± 24.56 ng/g) and day 14 (198.57 ± 26.26 ng/g) were nearly twofold higher than that in the control group (92.77 ± 14.98 ng/g). Histopathological analysis showed mild injury in the liver and kidney of rats subjected to oral administration of realgar for 14 days. As in the XEZBW groups, a mild injury in these organs was observed after administration for 14 days. This study inferred that the toxicity of arsenic was concentration- and time-dependent. The accumulation of DMA, a byproduct of choline metabolism, was responsible for inducing higher toxicity. Therefore, we concluded that measuring the levels of DMA, instead of total arsenic, might be more suitable for evaluating the toxicity of realgar-containing traditional Chinese medicines.

1H NMR studies on serum metabonomic changes over time in a kidney-Yang deficiency syndrome model

The central aim of this study was to investigate metabolite changes in metabolic pathwaysviametabonomic approaches in rats suffering from Kidney-Yang Deficiency Syndrome (KYDS) induced by hydrocortisone.

1HNMR-based metabonomic study of sub-chronic hepatotoxicity induced by realgar

ETHNOPHARMACOLOGICAL RELEVANCE

Realgar has been used as a traditional Chinese medicine (TCM) for thousands of years. Recently, a number of realgar or realgar-containing medicines poisoning cases have been reported. However, the toxicological mechanism of realgar has not been clearly clarified. In present study, the subchronic hepatotoxicity of realgar on mice was investigated using ¹HNMR-based metabonomic approaches.

MATERIALS AND METHODS

Twenty-eight male mice were divided into control group and low (0.15g/kg), middle (0.45g/kg), high (1.35g/kg) dosage realgar exposed groups. Their plasma and urine samples were used for NMR spectroscopic metabolic profiling. Principal component analysis (PCA) and pathway analysis were used to detect the hepatotoxic effects of realgar. Liver histopathological examination and plasma clinical chemistry analyses were also performed.

RESULTS

Plasma clinical chemistry analyses showed increased levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total protein (TP), total cholesterol (TC) and choline esterase (CHE) in realgar-exposed mice indicating liver injury. The PCA score plots showed the metabolic profiles of realgar-exposed mice apparently separated from the controls. Obvious dose-dependent changes of metabolites in urine and plasma of realgar-exposed mice were observed. From the loading plots and boxplots results, the concentrations of VLDL/LDL, 3-HB, lactate, acetate, acetoacetate, creatine, glutamate, methionine, NAc, TMAO, alanine in plasma and pyruvate, succinate, 2-oxoglutarate, DMA, citrate, hippurate, glycine, taurine, phenylalanine, lactate in urine were significantly changed in realgar-exposed mice. The change trends of metabolites in urine and plasma from mice sub-chronic exposed to realgar are similar to those reported in rats acute exposed to realgar, which indicate the acute and sub-chronic toxic mechanism of realgar are same. The disturbed metabolic pathway include energy metabolism, amino acids metabolism and gut bacteria metabolism.

CONCLUSIONS

The present work illustrated the NMR-based metabonomic approach can capture and probe the metabolic alterations induced by traditional Chinese medicine in the toxicological effects.

1H NMR-based metabonomic study on the effects of Epimedium on glucocorticoid-induced osteoporosis

Glucocorticoids are widely used in clinical practice for the treatment of many immune-mediated and inflammatory diseases, and glucocorticoid-induced osteoporosis (GIO) is the most common type of secondary osteoporosis. Epimedium is one of the most commonly used traditional Chinese medicines for treating osteoporosis. In the present study, we systematically analysed the metabonomic characteristics of GIO model rats and elucidated the therapeutic effect of Epimedium by using a ¹H NMR-based metabonomic approach in conjunction with multivariate data analysis. Rats in treatment and model groups were injected with dexamethasone (0.1mg/kg/day) for 5 weeks. Simultaneously, two treatment groups were orally administered Epimedium (10g/kg/day) or Alendronate (1.2mg/kg/day) for 5 weeks. In GIO model rats, lipid and lactate levels in serum were increased, while creatine/creatinine, PC/GPC, taurine, glycine and β-glucose levels were decreased. In urine, GIO rats had higher levels of phenylacetylglycine but lower levels of 2-oxoglutarate, citrate, creatine/creatinine, taurine, PC/GPC and hippurate than controls. Epimedium reversed the aforementioned metabolic alterations in multiple metabolic pathways involved in energy, lipid, amino acid and phospholipid metabolism and gut microbiota derangement. Our results indicated that Epimedium had significant effects in the prevention and treatment of osteoporosis. It is concluded that ¹H NMR metabonomics is a useful method for studying the metabolic effects of traditional Chinese medicine from a systematic and holistic view.

A metabolic profiling analysis of the nephrotoxicity of acyclovir in rats using ultra performance liquid chromatography/mass spectrometry

Acyclovir (ACV) exposure is a common cause of acute kidney injury (AKI). The toxicity mechanism of ACV has always been a matter of debate. The present study investigated into the time-effect relationship and dose-effect relationship of ACV-induced nephrotoxicity in rats using metabonomics. Twenty-four rats were randomly divided into four groups: a 0.9% NaCl solution group, and 100, 300, and 600mg/kg ACV-treated groups; the ACV or vehicle solution was administered with a single intravenous injection. Urine was collected at different time periods (12h before administration, and 0-6h, 7-12h, and 13-24h after administration). Routine urinalysis was conducted by a urine automatic analyzer. Renal markers, including urine urea nitrogen, urine creatinine, and urinary N-acetyl-β-d-glucosaminidase (NAG) activity, were determined using established protocols. Urinary metabolites were evaluated using ultra performance liquid chromatography/mass spectrometry (UPLC/MS). In the ACV-treated rats, increased levels of protein (PRO), occult blood (BLD), white blood cell (WBC), and NAG activity in urine were observed, while the urine creatinine and urea nitrogen levels showed a decrease compared with the control. Moreover, urine metabolites significantly changed after the treatment with ACV, and all the effects induced by ACV were dose-time dependent. Finally, 4 metabolites (guanine, 4-guanidinobutyric acid, creatinine, and urea) were identified, which can be used for further research on the mechanism of ACV-induced nephrotoxicity.

Therapeutic effect of flaxseed oil on experimental pulmonary fibrosis induced by bleomycin in rats

Pulmonary fibrosis is a chronic progressive disorder in which excessive deposition of extracellular matrix leads to irreversible scarring to interstitial lung tissue. In this study, we search to evaluate the therapeutic effect of flaxseed oil (FO) in experimental bleomycin (BLM)-induced pulmonary fibrosis. During our study, 30 male Wistar rats (weight range, 180–220 g) were divided into three groups: the control group (W) received no treatment; the second group (C) received BLM; and the third group (T) received BLM and FO for 21 days. Metabolites present in the bronchoalveolar lavage fluid (BALF) marking the changes obtained following treatment with FO were determined, histological changes in the lungs were evaluated, fatty acids present in lungs and erythrocytes of rats groups were determined by gas chromatography, and oxidative stress and antioxidant enzyme activity in the lung tissue were also recorded. Our results displayed that rat body weight decreased while fibrosis score and inflammatory index in lung tissue were significantly increased after bleomycin instillation. Administration of bleomycin followed by FO treatment reduced bleomycin-induced weight loss, increased proline, glucose, and glycerid rates in BALF and which are characterized by their anti-inflammatory effect and confirming the histological results proved by a decrease in inflammatory index and fibrosis score. This oil also significantly reduced thiobarbitunic acid reactive substance levels in the lungs of rats and increased levels of SOD and CAT and increased fatty acids levels promoting anti-inflammatory reactions especially in erythrocytes (linoleic, arachidonic, docosapentaenoic, and dihomo-γ-linoleic acids). In conclusion, these findings indicate that FO treatment significantly attenuated the increased pulmonary damage induced by bleomycin.

(1)H NMR-based metabonomics revealed protective effect of Naodesheng bioactive extract on ischemic stroke rats

ETHNOPHARMACOLOGICAL RELEVANCE

Stroke is a leading cause of death and disability in the world. However, current therapies are limited. Naodesheng, a widely used traditional Chinese medicine prescription, has shown a good clinical curative effect on ischemic stroke. Also, Naodesheng has been suggested to have neuroprotective effect on focal cerebral ischemia rats, but the underlying molecular mechanism remains unclear.

AIM OF THE STUDY

The present study was designed to evaluate the effect of Naodesheng bioactive extract on the metabolic changes in brain tissue, plasma and urine induced by cerebral ischemia perfusion injury, and explore the possible metabolic mechanisms by using a (1)H NMR-based metabonomics approach.

MATERIALS AND METHODS

A middle cerebral artery occlusion rat model was established and confirmed by the experiments of neurobehavioral abnormality evaluation, brain tissue TTC staining and pathological examination. The metabolic changes in brain tissue, plasma and urine were then assessed by a (1)H NMR technique combined with multivariate statistical analysis method.

RESULTS

These NMR data showed that cerebral ischemia reperfusion induced great metabolic disorders in brain tissue, plasma and urine metabolisms. However, Naodesheng bioactive extract could reverse most of the imbalanced metabolites. Meanwhile, it was found that both the medium and high dosages of Naodesheng bioactive extract were more effective on the metabolic changes than the low dosage, consistent with histopathological assessments.

CONCLUSIONS

These results revealed that Naodesheng had protective effect on ischemic stroke rats and the underlying mechanisms involved multiple metabolic pathways, including energy metabolism, amino acid metabolism, oxidative stress and inflammatory injury. The present study could provide evidence that metabonomics revealed its capacity to evaluate the holistic efficacy of traditional Chinese medicine and explore the underlying mechanisms.

Urinary metabonomic study of Panax ginseng in deficiency of vital energy rat using ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry

ETHNOPHARMACOLOGICAL RELEVANCE

Deficiency of vital energy (DE) is called Qi-deficiency, a traditional Chinese medicine syndrome. It is an indicator of a disease emerging though fuzzy, dynamic, complex, nonspecific and subjective. Ginseng is regarded as the king of herbs. It is famous for the function of replenishing qi in traditional Chinese medicine. It has treatment potential for DE caused by various reasons. This study aimed to investigate the mechanism of ginseng treating symptom DE with the method of metabolomics.

MATERIALS AND METHODS

Thirty-five rats were randomly divided into three groups: normal control group, DE model group and ginseng treatment group. The DE model rats were administered daily with ginseng decoctiondecoctiondecoction intragastrically and others with water for 15 days. Urine was analyzed with ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Principal component analysis (PCA) and orthogonal projection to latent structures squares-discriminant analysis (OPLS-DA) were built to distinguish the three groups in this study and find potential biomarkers.

RESULTS

The three groups are clearly separated and find out their metabolic distinction in PCA score plots. It showed that the metabolic profile of ginseng treatment group was changed to normal control group after administration of ginseng. Fifteen potential biomarkers are identified by OPLS-DA including Xanthurenic acid, kynurenic acid, Pantothenic acid, which are chiefly involved in tryptophan metabolism, taurine and hypotaurine metabolism, citric acid cycle, bile acid biosynthesis, alpha linolenic acid and linoleic acid metabolism. These biomarkers and the networks of their corresponding pathways will help to explain the mechanism of DE and ginseng treatment.

CONCLUSIONS

The results of blood biochemical indicators routine and urinary metabonomic reveal that ginseng have good abilities to regulate the energy metabolism, immune function and antioxidant activities. And UPLC-Q-TOF-MS-based metabolomics can provide useful information for the understanding of metabolic changes in DE rats after administration of ginseng in urine. The biomarkers and their corresponding pathways will provide further information of the mechanisms of ginseng in treating DE. This work also proves that the method of metabonomics is effective in traditional Chinese medicinal research.

Supplementation with Folic Acid, but Not Creatine, Increases Plasma Betaine, Decreases Plasma Dimethylglycine, and Prevents a Decrease in Plasma Choline in Arsenic-Exposed Bangladeshi Adults

BACKGROUND

Folic acid (FA) supplementation facilitates urinary excretion of arsenic, a human carcinogen. A better understanding of interactions between one-carbon metabolism intermediates may improve the ability to design nutrition interventions that further facilitate arsenic excretion.

OBJECTIVE

The objective was to determine if FA and/or creatine supplementation increase choline and betaine and decrease dimethylglycine (DMG).

METHODS

We conducted a secondary analysis of the Folic Acid and Creatine Trial, a randomized trial in arsenic-exposed Bangladeshi adults (n = 605, aged 24-55 y, 50.3% male) who received arsenic-removal water filters. We examined treatment effects of FA and/or creatine supplementation on plasma choline, betaine, and DMG concentrations, measured by LC-tandem mass spectrometry at baseline and at week 12. Group comparisons were between 1) 400 and 800 μg FA/d (FA400 and FA800, respectively) compared with placebo, 2) creatine (3 g/d) compared with placebo, and 3) creatine plus FA400 compared with FA400.

RESULTS

Choline decreased in the placebo group (-6.6%; 95% CI: -10.2%, -2.9%) but did not change in the FA groups (FA400: 2.5%; 95% CI: -0.9%, 6.1%; FA800: 1.4%; 95% CI: -2.5%, 5.5%; P < 0.05). Betaine did not change in the placebo group (-3.5%; 95% CI: -9.3%, 2.6%) but increased in the FA groups (FA400: 14.1%; 95% CI: 9.4%, 19.0%; FA800: 13.0%; 95% CI: 7.2%, 19.1%; P < 0.01). The decrease in DMG was greater in the FA groups (FA400: -26.7%; 95% CI: -30.9%, -22.2%; FA800: -27.8%; 95% CI: -31.8%, -23.4%) than in the placebo group (-12.3%; 95% CI: -18.1%, -6.2%; P < 0.01). The percentage change in choline, betaine, and DMG did not differ between creatine treatment arms and their respective reference groups.

CONCLUSION

Supplementation for 12 wk with FA, but not creatine, increases plasma betaine, decreases plasma DMG, and prevents a decrease in plasma choline in arsenic-exposed Bangladeshi adults. This trial was registered at clinicaltrials.gov as NCT01050556.

The interactive effects of mercury and selenium on metabolic profiles, gene expression and antioxidant enzymes in halophyte Suaeda salsa

Suaeda salsa is the pioneer halophyte in the Yellow River Delta and was consumed as a popular vegetable. Mercury has become a highly risky contaminant in the sediment of intertidal zones of the Yellow River Delta. In this work, we investigated the interactive effects of mercury and selenium in S. salsa on the basis of metabolic profiling, antioxidant enzyme activities and gene expression quantification. Our results showed that mercury exposure (20 μg L(-1)) inhibited plant growth of S. salsa and induced significant metabolic responses and altered expression levels of INPS, CMO, and MDH in S. salsa samples, together with the increased activities of antioxidant enzymes including SOD and POD. Overall, these results indicated osmotic and oxidative stresses, disturbed protein degradation and energy metabolism change in S. salsa after mercury exposures. Additionally, the addition of selenium could induce both antagonistic and synergistic effects including alleviating protein degradation and aggravating osmotic stress caused by mercury.

Metabolomic Characterizations of Liver Injury Caused by Acute Arsenic Toxicity in Zebrafish

Arsenic is one of the most common metalloid contaminants in groundwater and it has both acute and chronic toxicity affecting multiple organs. Details of the mechanism of arsenic toxicity are still lacking and profile studies at metabolic level are very limited. Using gas chromatography coupled with mass spectroscopy (GC/MS), we first generated metabolomic profiles from the livers of arsenic-treated zebrafish and identified 34 significantly altered metabolite peaks as potential markers, including four prominent ones: cholic acid, glycylglycine, glycine and hypotaurine. Combined results from GC/MS, histological examination and pathway analyses suggested a series of alterations, including apoptosis, glycogenolysis, changes in amino acid metabolism and fatty acid composition, accumulation of bile acids and fats, and disturbance in glycolysis related energy metabolism. The alterations in glycolysis partially resemble Warburg effect commonly observed in many cancer cells. However, cellular damages were not reflected in two conventional liver function tests performed, Bilirubin assay and alanine aminotransferase (ALT) assay, probably because the short arsenate exposure was insufficient to induce detectable damage. This study demonstrated that metabolic changes could reflect mild liver impairments induced by arsenic exposure, which underscored their potential in reporting early liver injury.

Therapeutic Effects of Chinese Medicine Herb Pair, Huzhang and Guizhi, on Monosodium Urate Crystal-Induced Gouty Arthritis in Rats Revealed by Anti-Inflammatory Assessments and NMR-Based Metabonomics

The present study was undertaken to evaluate the therapeutic effects of Huzhang-Guizhi herb pair (HG), firstly included in Hu-Zhang Power documented in Taiping Shenghui Fang, on monosodium urate (MSU) crystals-induced gouty arthritis in rats. We found that pretreatment with HG in rats with gouty arthritis could significantly attenuate the ankle joint swelling, and this beneficial antigout effect might be mediated, at least in part, by inhibiting tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) production in synovial fluid as well as nuclear transcription factor-κB p65 (NF-κB p65) protein expression in synovial tissue. Moreover, metabonomic analysis demonstrated that 5 and 6 potential biomarkers associated with gouty arthritis in plasma and urine, respectively, which were mainly involved in energy metabolism, amino acid metabolism, and gut microbe metabolism, were identified. HG could reverse the pathological process of MSU-induced gouty arthritis through regulating the disturbed metabolic pathways. These results provided important mechanistic insights into the protective effects of HG against MSU-induced gouty arthritis in rats.

Metabolomics and its application to the evaluation of the efficacy and toxicity of traditional Chinese herb medicines

Traditional Chinese herb medicines (TCHMs) have been used in the treatment of a variety of diseases for thousands of years in Asian countries. The active components of TCHMs usually exert combined synergistic therapeutic effects on multiple targets, but with less potential therapeutic effect based on routine indices than Western drugs. These complex effects make the assessment of the efficacy of TCHMs and the clarification of their underlying mechanisms very challenging, and therefore hinder their wider application and acceptance. Metabolomics is a crucial part of systems biology. It allows the quantitative measurement of large numbers of the low-molecular endogenous metabolites involved in metabolic pathways, and thus reflects the fundamental metabolism status of the body. Recently, dozens of metabolomic studies have been devoted to prove the efficacy/safety, explore the underlying mechanisms, and identify the potential biomarkers to access the action targets of TCHMs, with fruitful results. This article presents an overview of these studies, focusing on the progress made in exploring the pharmacology and toxicology of various herbal medicines.

Blood, urine and faecal metabolite profiles in the study of adult renal disease

Chronic kidney disease (CKD) is a major public health burden and to date traditional biomarkers of renal function (such as serum creatinine and cystatin C) are unable to identify at-risk individuals before the disease process is well under way. To help preventive strategies and maximize the potential for effective interventions, it is important to characterise the molecular changes that take place in the development of renal damage. Metabolomics is a promising tool to identify markers of renal disease since the kidneys are involved in the handling of major biochemical classes of metabolites. These metabolite levels capture a snap-shot of the metabolic profile of the individual, allowing for the potential identification of early biomarkers, and the monitoring of real-time kidney function. In this review, we describe the current status of the identification of blood/urine/faecal metabolic biomarkers in different entities of kidney diseases including: acute kidney injury, chronic kidney disease, renal transplant, diabetic nephropathy and other disorders.