Serum and kidney metabolic changes of rat nephrotoxicity induced by Morning Glory Seed

Pharbitidis Semen: A review of botany, traditional uses, phytochemistry, pharmacology, and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Pharbitidis Semen (the seeds of Ipomoea nil (L.) Roth or Ipomoea purpurea (L.) Roth), a popular traditional Chinese medicine, is also known as "Heichou" or "Baichou" (Chinese: , ). It can purge the bowels, promote diuresis, remove stagnated accumulation, and kill worms. It can be used for treating anasarca with constipation and oliguria; dyspnea and cough caused by retained fluid; abdominal pain because of intestinal parasitosis; ascariasis; and taeniasis.

AIMS

This review discusses the botany, ethnopharmacology, phytochemistry, pharmacological activities, toxicology, and quality control of Pharbitidis Semen, to obtain a complete understanding of its effects and provide a basis for further research and the development of new drugs.

MATERIALS AND METHODS

The literature on Pharbitidis Semen is mainly obtained from pharmacopoeias of different countries, masterpieces of traditional Chinese medicine, Master's and Ph.D. theses, and published articles obtained from literature retrieval websites, such as CNKI, PubMed, SciFinder, WanFang data, Web of Science, Springer, ScienceDirect, Wiley, ACS Publications, Taylor & Francis, J-STAGE, and Google Scholar. Its botany, ethnopharmacology, phytochemistry, pharmacological activities, toxicology, and quality control are discussed to understand its effects and provide a basis for further research.

RESULTS

Pharbitidis semen has been used ethnomedically in many tropical and subtropical countries as deobstruents, diuretics, and anthelmintics. About 170 chemical compounds, including terpenoids, phenylpropanoids, resin glycosides, fatty acids and other compounds, have been isolated. It has been reported to have different effects, including laxative, renal-protective, neuroprotective, insecticidal, antitumor, anti-inflammatory, and antioxidant. Moreover, a brief introduction to processing, toxicity, and quality control is provided.

CONCLUSIONS

The traditional efficacy of Pharbitidis Semen in diarrhea has been confirmed, but its bioactive and toxic ingredients are not entirely clear. It is necessary to strengthen the research and identification of effective parts or natural active components of Pharbitidis Semen, clarify the molecular mechanism of its toxicity and change rule of endogenous substances to make Pharbitidis Semen better used in clinical practice. Additionally, the imperfect quality standard is also a challenge that must be solved urgently. The study of modern pharmacology has broadened the application of Pharbitidis Semen and provided ideas for better utilization of this resource.

Protective effects of Brownea grandiceps (Jacq.) against ϒ-radiation-induced enteritis in rats in relation to its secondary metabolome fingerprint

Radiation enteritis is the most common complication of radiotherapy in patients with pelvic malignancies. Thus, the radioprotective activity of the total hydro-alcoholic extract (BGE) and the ethyl acetate soluble fraction (EAF) of Brownea grandiceps leaves was evaluated against ϒ-radiation-induced enteritis in rats. (BGE) and (EAF) were characterized using HPLC-PDA-ESI-MS/MS analysis. The total phenolic and flavonoid contents were also quantified. In vivo administration of (BGE) (400 mg/kg) and (EAF) (200 & 400 mg/kg) prevented intestinal injury and maintained the mucosal integrity of irradiated rats through increasing villi length and promoting crypt regeneration. Also, (EAF) showed more potent antioxidant activity than (BGE) through reduction of MDA level and enhancement of GSH content and catalase enzyme activity. (BGE) and (EAF) down-regulated intestinal NF-κB expression leading to diminished expression of downstream inflammatory cytokine TNF-α. Moreover, (EAF) markedly reduced the expression of profibrotic marker TGF-β1. Seventy-nine compounds were tentatively identified, including flavonoids, proanthocyanidins, polar lipids and phenolic acids. (EAF) showed significantly higher total phenolic and flavonoid contents, as compared to (BGE). Results revealed remarkable radioprotective activity of (BGE) and (EAF), with significantly higher activity for (EAF). The chemical constituents of (BGE) and (EAF) strongly supported their radioprotective activity. To the best of our knowledge, the present study describes for the first time the radioprotective activity of B. grandiceps leaves in relation to its secondary metabolome fingerprint; emphasizing the great promise of B. grandiceps leaves, especially (EAF), to be used as natural radio-protective agent.

Investigation of the incompatibility of Knoxiae Radix and Glycyrrhizae Radix et Rhizoma in rats by 1 H NMR and MS-based untargeted metabolomic analysis

Knoxiae Radix (HDJ, usually used after being processed into CHDJ) is a traditional Chinese herbal medicine that has been recorded in the Chinese Pharmacopoeia for many years. It is said that Glycyrrhizae Radix et Rhizoma (GC) is incompatible with HDJ, but this is unproven. In this work, nontargeted metabolomics experiments were performed on rats to evaluate the effect of the combination of the two herbals. For this, we conducted a 28-day administration in rats. The plasma, urine and kidney tissues were collected for a metabolomics study based on ¹ H NMR and LC-MS. The OPLS-DA method was used to screen biomarkers. In addition, the KEGG Pathway database and MetaboAnalyst were used to find metabolic pathways. Twenty-two significant metabolites were identified. These metabolites were related to many metabolic pathways such as amino acid metabolism, synthesis and degradation of ketone bodies. Significant changes in urine creatinine levels revealed that CHDJ is nephrotoxic. When the GC-CHDJ mass ratio was 1, the toxicity was strengthened; when the GC-CHDJ' mass ratio was 3, the toxicity was alleviated. This is the first time that a metabolomics approach has been used to investigate the incompatibility of GC-CHDJ.

Hepatotoxicity and nephrotoxicity assessment on ethanol extract of Fructus Psoraleae in Sprague Dawley rats using a UPLC-Q-TOF-MS analysis of serum metabolomics

Fructus Psoraleae (FP) is commonly used in the treatment of vitiligo, osteoporosis, and other diseases in clinic. As a result, the toxicity caused by FP is frequently encountered in clinical practice; however, the underlying toxicity mechanism remains unclear. The purpose of this study was to investigate the toxic effect of the ethanol extract of FP (EEFP) in rats and to explore the underlying toxic mechanisms using a metabolomics approach. The toxicity was evaluated by hematological indicators, biochemical indicators, and histological changes. In addition, a serum metabolomic method based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight MS (UPLC-Q-TOF-MS) had been established to investigate the hepatorenal toxicity of FP. Multivariate statistical approaches, such as partial least squares discriminant analysis and orthogonal partial least squares discriminant analysis, were built to evaluate the toxic effects of FP and find potential biomarkers and metabolic pathways. Ten endogenous metabolites had been identified and the related metabolic pathways were involved in phospholipid metabolism, amino acid metabolism, purine metabolism, and antioxidant system activities. The results showed that long-term exposure to high-dose EEFP may cause hepatorenal toxicity in rats. Therefore, serum metabolomics can improve the diagnostic efficiency of FP toxicity and make it more accurate and comprehensive.

Morning glory seed keeps laxative effect while retains less subchronic toxicity after being fried

ETHNOPHARMACOLOGICAL RELEVANCE

Morning glory seed (MGS), has been widely used in treating constipation especially towards children. Clinically, people usually take fried MGS (MGSF) in formulas to reduce its side effect. However, the safety of MGSF other than MGS has yet to be explored.

OBJECTIVE

The study aimed to reveal the potential mechanisms of using MGSF instead of MGS basing on chemistry, pharmacodynamics and toxicology.

METHODS

The chemical compositions of the extracts of MGS and MGSF were compared using UPLC-Q-TOF/MS method. Simultaneously, to prove the availability and safety of MGSF, we investigated the laxative effect and subchronic toxicity of MGS and MGSF and addressed the mechanism of laxative effect of them.

RESULTS

In this study, less phenolic acids and more fatty acids were detected in MGSF compared with the compounds in MGS. Moreover, we found that MGS group had stronger laxative effect than MGSF group via downregulating the expression of AQP3 protein. As for subchronic toxicity test, the body weights of MGS group were lower than MGSF group. In serum biochemistry and histopathological examinations, MGS group could cause more serious toxicity in liver, kidney and colon than MGSF group with higher values of BUN, Cr, AST and ALP.

CONCLUSION

Based on the findings in this study, MGSF with varied compounds contents could still keep the laxative effect while retain less subchronic toxicity, which emphasized the necessity of processing and provided an insight into the rational use of MGSF in clinical practice.

New insights into the vancomycin-induced nephrotoxicity using in vitro metabolomics combined with physiologically based pharmacokinetic modeling

Vancomycin is a first-line treatment for invasive infections caused by multidrug-resistant gram-positive bacteria. However, vancomycin-induced nephrotoxicity is an increasing burden, particularly in patients with complex life-threatening conditions. Vancomycin-induced nephrotoxicity associated with clinically relevant exposure on the target site has not been well defined. This study aimed to acquire the concentration of vancomycin in the renal tubules and kidneys in humans using physiologically based pharmacokinetic (PBPK) modeling and simulation. Based upon the exposure of vancomycin in the renal tubule, the toxicity of vancomycin in human renal proximal tubular epithelial cells was examined with the XTT assay and in vitro metabolomics analysis. A rat PBPK model predicting plasma and kidney concentration-time profiles of vancomycin matched the observed behavior after a single administration of 10 mg/kg. The concentration of vancomycin in renal tubules was about 40-50 times higher than that in plasma. The human PBPK model transferred from the rat model predicted renal tubule concentrations of vancomycin as 316.1-2136.6 μg/mL at 500 mg every 6 hours, and 199.0-3932.5 μg/mL at 1000 mg every 12 hours. Vancomycin showed significant nephrotoxicity at 4 mg/mL in XTT assessment. In total, 11 lysophosphatidylcholines and one lysophosphatidylethanolamine were identified by metabolomics analysis. The concentration-dependent increase was evident in the release of lysophospholipids after vancomycin treatment (0.125-4 mg/mL) for 24 hours. Our study revealed the relationship between the exposure of vancomycin in the kidney and toxicity of vancomycin at clinically relevant concentrations achieved from a mechanical PBPK model. A series of lysophospholipids as potential metabolic markers of renal toxicity were identified.

UPLC-HDMS-based on serum metabolomics reveals the toxicity of arecae semen

ETHNOPHARMACOLOGICAL RELEVANCE

Arecae semen has been used as vermifuge and digestant in traditional Chinese medicine (TCM) for more than one thousand years. However, the toxicity effect of areca semen and its underlying mechanism are still unclear.

THE AIM OF THE STUDY

This study was aimed to investigate the toxicity of arecae semen and to explore its mechanisms by serum metabolomics.

MATERIALS AND METHODS

The male Wistar rats were divided into the control group and treated group (n = 6 in each group), which were given by gavage with distill water or arecae semen aqueous extract (ASAE) once a day for 30 days, respectively. Serum samples were collected from all the rats after treatment of 7-day, 14-day and 30-day for metabolomics analysis. Moreover, biochemistry analysis and histopathological examination were performed at the end of study.

RESULTS

The phenomenon of diarrhea, less physical activity, tremors and body curl up were observed in the treated group. Additionally, the body weights of treated rats were significantly decreased compared with control rats from the 8th day after oral administration. Except the level of creatinekinase (CK) in the treated group significantly increased compared with the control group, there were no differences on biochemistry parameters and histopathological test in the two groups. Combined with the methods of principal component analysis (PCA), orthogonal projection to latent structure-discrimination analysis (OPLS-DA) and available databases, the treated and control rats were clearly distinguished from each other and 19 metabolites were identified as the potential biomarkers in the arecae semen treated rats. The identified biomarkers indicated that there were perturbations of the phospholipid metabolism, amino acid metabolism and fat acid metabolism in the treated group.

CONCLUSIONS

This indicated that arecae semen possessed certain cardiotoxicity and inhibited the normal growth in Wistar male rats. In addition, the metabolomics approach is a useful tool to study the toxicity in TCM.

Application of metabolomics in toxicity evaluation of traditional Chinese medicines

Traditional Chinese medicines (TCM) have a long history of use because of its potential complementary therapy and fewer adverse effects. However, the toxicity and safety issues of TCM have drawn considerable attention in the past two decades. Metabolomics is an “omics” approach that aims to comprehensively analyze all metabolites in biological samples. In agreement with the holistic concept of TCM, metabolomics has shown great potential in efficacy and toxicity evaluation of TCM. Recently, a large amount of metabolomic researches have been devoted to exploring the mechanism of toxicity induced by TCM, such as hepatotoxicity, nephrotoxicity, and cardiotoxicity. In this paper, the application of metabolomics in toxicity evaluation of bioactive compounds, TCM extracts and TCM prescriptions are reviewed, and the potential problems and further perspectives for application of metabolomics in toxicological studies are also discussed.

Metabonomics analysis of quercetin against the nephrotoxicity of acrylamide in rats

This research aimed at studying the effect of quercetin against the nephrotoxicity of acrylamide by metabonomics analysis of kidney tissue.

An integrative investigation of the toxicity of Aconiti kusnezoffii radix and the attenuation effect of its processed drug using a UHPLC-Q-TOF based rat serum and urine metabolomics strategy

Aconiti kusnezoffii radix (AKR), the root of Aconitum kusnezoffii Reichb., is commonly used in the treatment of the rheumatoid arthritis. However, the clinical application is limited due to its potential toxicity. Therefore, to investigate the mechanism of its potential neurotoxicity and nephrotoxicity, a comprehensive metabolomics study combined with serum biochemistry and histopathology measurements was carried out. A UHPLC-Q-TOF mass spectrometry based metabolomics approach was applied to characterize the AKR toxicity, while the toxicity attenuation effects of Aconiti kusnezoffii radix cocta (AKRC) on Wistar rats were also investigated. Two chromatographic techniques involving reversed-phase chromatography and hydrophilic interaction chromatography were combined for the serum and urine detection, which balanced the integrity and selectivity of the two matrices. Principal component analysis was used to determine the groups, and principal component analysis discriminant analysis was carried out to confirm the important variables. Then, the developed integrative toxicity evaluation method was applied to assess the toxicity of AKR and the attenuation effect of AKRC. The highly sensitive and specific toxic biomarkers, which can provide practical bases were identified for the diagnosis of the neurotoxicity and nephrotoxicity induced by AKR. In all, a total of 19 putative biomarkers were characterized, and related metabolic pathways were identified. The study demonstrated that the established metabolomics strategy is a powerful approach for investigating the mechanisms of herbal toxicity and the attenuation effect of a processing method and would provide medical solutions for other toxic herbal medications and further clinical evidence on how AKR improves symptoms of rheumatoid arthritis patients.

Potential urinary biomarkers of nephrotoxicity in cyclophosphamide-treated rats investigated by NMR-based metabolic profiling

The anticancer-drug cyclophosphamide (CP) is known to have nephrotoxicity. The aim of this study was to identify urinary biomarkers indicating CP-induced nephrotoxicity. We investigated the urine metabolic profiles using nuclear magnetic resonance spectrometry of rats administered with single high-doses of CP (0, 30, and 100 mg/kg body weight) and daily low-doses over a 4-week period (0, 1, 3, and 10 mg/kg body weight). Among 18 identified urinary metabolites, 2-oxoglutarate, citrate, hippurate, formate, valine, and alanine for short-term and 2-oxoglutarate, citrate, hippurate, isoleucine, leucine, allantoin, valine, and lysine for long-term were selected as potential biomarkers. Pathway-enrichment analysis suggested that the urinary metabolism of CP is related to valine, leucine, and isoleucine biosynthesis; taurine and hypotaurine metabolism; glyoxylate and dicarboxylate metabolism; citrate cycle; and alanine, aspartate, and glutamate metabolism, with high pathway impact. The potential biomarkers obtained in this study could be used to monitor CP-induced nephrotoxicity relative to dose and treatment time.

Metabolomics as a tool to evaluate the toxicity of formulations containing amphotericin B, an antileishmanial drug

Amphotericin B (AmB) is a drug of choice against life-threatening systemic fungal infections and an alternative therapy for the treatment of all forms of leishmaniasis. It is known that AmB and its conventional formulation cause renal damage; however, the lipid formulations can reduce these effects. The aim of the present study was to identify metabolic changes in mice treated with two different AmB formulations, a nanoemulsion (NE) (lipid system carrier) loaded with AmB and the conventional formulation (C-AmB). For this purpose, metabolic fingerprinting represents a valuable strategy to monitor, in a non-targeted manner, the changes that are at the base of the toxicity mechanism of AmB. Plasma samples of BALB-c mice were collected after treatment with 3 alternate doses of AmB at 1 mg kg-1 administered intravenously and analysed with CE, LC and GC coupled to MS. Blood urea nitrogen (BUN) and plasma creatinine levels were also analysed. Kidney tissue specimens were collected and evaluated. It was not observed that there were any alterations in BUN and creatinine levels as well as in histopathological analysis. Approximately 30 metabolites were identified as potentially related to early C-AmB-induced nephrotoxicity. Disturbances in the arachidonic acid, glycerophospholipid, acylcarnitine and polyunsaturated fatty acid (PUFA) pathways were observed in C-AmB-treated mice. In the AmB-loaded NE group, it was observed that there were fewer metabolic changes, including changes in the plasma levels of cortisol and pyranose. The candidate biomarkers revealed in this study could be useful in the detection of the onset and severity of kidney injury induced by AmB formulations.

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.

Metabolic biomarkers for chronic kidney disease

Chronic kidney disease (CKD) is an increasingly recognized burden for patients and health care systems with high (and growing) global incidence and prevalence, significant mortality, and disproportionately high treatment costs. Yet, the available diagnostic tools are either impractical in clinical routine or have serious shortcomings impeding a well-informed disease management although optimized treatment strategies with proven benefits for the patients have become available. Advances in bioanalytical technologies have facilitated studies that identified genomic, proteomic, and metabolic biomarker candidates, and confirmed some of them in independent cohorts. This review summarizes the CKD-related markers discovered so far, and focuses on compounds and pathways, for which there is quantitative data, substantiating evidence from translational research, and a mechanistic understanding of the processes involved. Also, multiparametric marker panels have been suggested that showed promising diagnostic and prognostic performance in initial analyses although the data basis from prospective trials is very limited. Large-scale studies, however, are underway and will provide the information for validating a set of parameters and discarding others. Finally, the path from clinical research to a routine application is discussed, focusing on potential obstacles such as the use of mass spectrometry, and the feasibility of obtaining regulatory approval for targeted metabolomics assays.

A pharmaco-metabonomic study on chronic kidney disease and therapeutic effect of ergone by UPLC-QTOF/HDMS

Chronic kidney disease (CKD) is an important public health problem. Ergone has been proved to prevent the progression of CKD. UPLC-QTOF/HDMS was employed for metabolic profiling of adenine-induced CKD and to investigate the nephroprotective effects of ergone. Pharmacology parameters including blood biochemistry, histopathological evaluation and Western blot analysis were performed concurrently. The UPLC-MS data were analyzed by partial least squares-discriminate analysis, correlation analysis, heatmap analysis and mapped to KEGG pathways. Blood and serum biochemistry were observed to be significantly different in the CKD group than in the control group. In conjunction with biochemistry, histopathology and protein expression results, identified metabolites indicated perturbations in fatty acid metabolism, purine metabolism and amino acid metabolism as changes associated with adenine-induced CKD and the interventions of ergone. Upregulated expression of TGF-β1, ED-1, CTGF, bFGF and collagen I was observed in the CKD group. However, downregulated expression of these proteins was observed after oral administration of ergone. These results suggest that expression changes in these proteins had implications for fatty acid metabolism, purine metabolism and amino acid metabolism in the development of CKD and that ergone treatment could delay the development of CKD by normalizing or blocking abnormal changes in biomarker metabolites and protein expression in the CKD group.

Evaluation of the indicative roles of seven potential biomarkers on hepato-nephrotoxicity induced by Genkwa Flos

ETHNOPHARMACOLOGICAL RELEVANCE

Genkwa Flos, a classical traditional Chinese medicine, is used for the definite antitumor activity and tends to be taken overdose or long term in these years. While the excessive application can result in damage to liver and kidney. In this study, the indicative roles of seven potential biomarkers were evaluated to investigate hepato-nephrotoxicity in the early stages after oral administration of Genkwa Flos for 14 days.

MATERIALS AND METHODS

Histopathology, serum biochemistry and seven potential biomarkers in serum or urine from male Sprague-Dawley rats were monitored. Hepatic and renal tissues were histopathologically examined to identify specific changes occurring. Routine serum biochemical parameters were tested by using standard clinical laboratory methods. Seven biomarkers including cholic acid, taurine, 5-oxoproline, hippuric acid, uric acid, 3-indoxyl sulfate and kynurenic acid were detected by a developed LC-MS method.

RESULTS

The histopathological alterations and the increased levels of serum biochemistry were detected on the 8th day after Genkwa Flos treated. The seven analytes were also found significantly changed in Genkwa Flos treated group, especially cholic acid, taurine, 5-oxoproline and hippuric acid which were changed on the 2nd or 4th day.

CONCLUSIONS

Although serum biochemistry and histopathology suggested that Genkwa Flos was responsible for the hepato-nephrotoxicity that occurred following the ingestion of this medicinal herb, evaluation of these biomarkers might be more beneficial for the early detection of liver and kidney injuries. This study could be further used in hepatic and renal failures caused by other reasons in the following research works.

Metabolomics in nephrotoxicity

Nephrotoxicity or renal toxicity can be a result of hemodynamic changes, direct injury to cells and tissue, inflammatory tissue injury, and/or obstruction of renal excretion. Nephrotoxicity is frequently induced by a wide spectrum of therapeutic drugs and environ mental pollutants. Knowledge of the complex molecular and pathophysiologic mechanisms leading to nephrotoxicity remains limited, in part, by research that historically focused on single or relatively few risk markers. As such, current kidney injury biomarkers are inadequate in terms of sensitivity and specificity. In contrast, metabolomics enables screening of a vast array of metabolites simultaneously using NMR and MS to assess their role in nephrotoxicity development and progression. A more comprehensive understanding of these biochemical pathways would also provide valuable insight to disease mechanisms critical for drug development and treatment.

RECENT ADVANCES IN ULTRA-HIGH PERFORMANCE LIQUID CHROMATOGRAPHY FOR THE ANALYSIS OF TRADITIONAL CHINESE MEDICINE

Traditional Chinese medicine has been widely used for the prevention and treatment of various diseases for thousands of years in China. Ultra-high performance liquid chromatography (UHPLC) is a relatively new technique offering new possibilities. This paper reviews recent developments in UHPLC in the separation and identification, fingerprinting, quantification, and metabolism of traditional Chinese medicine. Recently, the combination of UHPLC with MS has improved the efficiency of the analysis of these materials.

Metabolomics in chronic kidney disease

Chronic kidney disease (CKD) represents a major challenge to public healthcare. Traditional clinical biomarkers of renal function (blood urea nitrogen and serum creatinine) are not sensitive or specific enough and only increase significantly after the presence of substantial CKD. Therefore, more sensitive biomarkers of CKD are needed. CKD-specific biomarkers at an early disease stage and early diagnosis of specific renal diseases would enable improved therapeutic treatment and reduced the personal and financial burdens. The goal of metabolomics is to identify non-targeted, global small-molecule metabolite profiles of complex samples, such as biofluids and tissues. This method offers the potential for a holistic approach to clinical medicine, as well as improvements in disease diagnoses and the understanding of pathological mechanisms. This review article presents an overview of the recent developments in the field of metabolomics, followed by an in-depth discussion of its application to the study of CKD (primary, chronic glomerulonephritis such as IgA nephropathy; secondary, chronic renal injury such as diabetic nephropathy; chronic renal failure including end-stage kidney disease with and without undergoing replacement therapies, etc), including metabolomic analytical technologies, chemometrics, and metabolomics in experimental and clinical research. We describe the current status of the identification of metabolic biomarkers in CKD. Several markers have been confirmed across multiple studies to detect CKD earlier than traditional clinical chemical and histopathological methods. The application of metabolomics in CKD studies provides researchers the opportunity to gain new insights into metabolic profiling and pathophysiological mechanisms. Particular challenges in the field are presented and placed within the context of future applications of metabolomic approaches to the studies of CKD.

Toxicology and safety of the tincture of Operculina alata in patients with functional constipation

The tincture of Operculina alata, popularly known as "tincture of jalapa", is used in Northeast Brazil to treat constipation and encephalic vascular accident, but it has not yet been adequately tested for safety and efficacy. The aim of this study was to evaluate the toxicology and safety of the tincture of O. alata in patients with functional constipation. This was a double-blind, randomized, placebo-controlled clinical trial. The study consisted of three phases: pre-treatment, treatment and post-treatment, each phase with duration of seven days. Arterial pressure, heart rate, body weight, adverse events, hematological, metabolic, liver and kidney functions were monitored. Forty patients were randomized to receive tincture of O. alata and 43 patients to receive placebo. There were statistical differences in the clinical aspects between groups, but these changes were not considered clinically significant. Adverse events were considered not serious and of mild intensity, especially dizziness, headache, abdominal pain and nausea. This clinical trial confirmed the safety of the tincture of O. alata in the pharmaceutical form and dosage tested, allowing the product to be safely used in a larger population for the assessment of its clinical efficacy.

Review of current and "omics" methods for assessing the toxicity (genotoxicity, teratogenicity and nephrotoxicity) of herbal medicines and mushrooms

ETHNOPHARMACOLOGICAL RELEVANCE

The increasing use of traditional herbal medicines around the world requires more scientific evidence for their putative harmlessness. To this end, a plethora of methods exist, more or less satisfying. In this post-genome era, recent reviews are however scarce, not only on the use of new "omics" methods (transcriptomics, proteomics, metabonomics) for genotoxicity, teratogenicity, and nephrotoxicity assessment, but also on conventional ones.

METHODS

The present work aims (i) to review conventional methods used to assess genotoxicity, teratogenicity and nephrotoxicity of medicinal plants and mushrooms; (ii) to report recent progress in the use of "omics" technologies in this field; (iii) to underline advantages and limitations of promising methods; and lastly (iv) to suggest ways whereby the genotoxicity, teratogenicity, and nephrotoxicity assessment of traditional herbal medicines could be more predictive.

RESULTS

Literature and safety reports show that structural alerts, in silico and classical in vitro and in vivo predictive methods are often used. The current trend to develop "omics" technologies to assess genotoxicity, teratogenicity and nephrotoxicity is promising but most often relies on methods that are still not standardized and validated.

CONCLUSION

Hence, it is critical that toxicologists in industry, regulatory agencies and academic institutions develop a consensus, based on rigorous methods, about the reliability and interpretation of endpoints. It will also be important to regulate the integration of conventional methods for toxicity assessments with new "omics" technologies.

Applications of HPLC/MS in the analysis of traditional Chinese medicines

In China, traditional Chinese medicines (TCMs) have been used in clinical applications for thousands of years. The successful hyphenation of high-Performance liquid chromatography (HPLC) and mass spectrometry (MS) has been applied widely in TCMs and biological samples analysis. Undoubtedly, HPLC/MS technique has facilitated the understanding of the treatment mechanism of TCMs. We reviewed more than 350 published papers within the last 5 years on HPLC/MS in the analysis of TCMs. The present review focused on the applications of HPLC/MS in the component analysis, metabolites analysis, and pharmacokinetics of TCMs etc. 50% of the literature is related to the component analysis of TCMs, which show that this field is the most populär type of research. In the metabolites analysis, HPLC coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry has been demonstrated to be the powerful tool for the characterization of structural features and fragmentation behavior patterns. This paper presented a brief overview of the applications of HPLC/MS in the analysis of TCMs. HPLC/MS in the fingerprint analysis is reviewed elsewhere.

A metabonomic analysis of urine from rats treated with rhizoma alismatis using ultra-performance liquid chromatography/mass spectrometry

A metabonomic approach based on ultra-performance liquid chromatography coupled to mass spectrometry (UPLC/MS) was used to study the nephrotoxicity of rhizoma alismatis (RA) in rats. Potential biomarkers of RA toxicity were identified and the toxicological mechanism is discussed. Urine samples were collected from control and treated rats at various stages and analyzed by UPLC/MS in positive ionization mode. Histopathological analysis was used to evaluate renal function. The differences in the metabolic profiles of the control and treated rats were clearly distinguishable with principal components analysis (PCA) of the chromatographic data, and significant changes in 13 metabolite biomarkers were detected in the urine. This metabonomic method combined with PCA could discriminate the treated rats from the control rats on days 60, 120, and 180 after treatment, before serious organic renal damage was apparent on day 180 with histopathology. This research indicates that UPLC/MS-based metabonomic analysis of urine samples can be used to predict the chronic nephrotoxicity induced by rhizoma alismatis.

Potential role of metabolomics apporoaches in the area of traditional Chinese medicine: as pillars of the bridge between Chinese and Western medicine

Traditional Chinese medicine (TCM) is a holistic approach to health that attempts to bring the body, mind and spirit into harmony. Entering 21st century, TCM is getting more and more popular in the whole world for improving health condition of human beings and preventing or healing diseases, especially shows great advantages in early intervention, combination therapies and personalized medicine, etc. However, like almost all other ethnopharmacology, TCM also faces severe challenges and suffers from insufficient modern research owing to lack of scientific and technologic approaches, restricts the development of TCM in the world. Fortunately, a novel analytical technique, metabolomics (or metabonomics), adopts a 'top-down' strategy to reflect the function of organisms from terminal symptoms of metabolic network and understand metabolic changes of a complete system caused by interventions in holistic context. Its property consists with the holistic thinking of TCM, may beneficially provide an opportunity to scientifically express the meaning of evidence-based Chinese medicine, such as Chinese medicine syndromes (CMS), preventive treatment, action of Chinese medicine, Chinese medical formulae (CMF) and acupuncture efficacy. This review summarizes potential applications of robust metabolomics apporoaches in the area of traditional oriental medicine, and highlights the key role of metabolomics to resolve special TCM issues.