NMR-derived developmental metabolic trajectories: an approach for visualizing the toxic actions of trichloroethylene during embryogenesis

Fish embryo toxicity tests for chemical risk assessment have traditionally been based upon non-specific endpoints including morphological abnormalities, hatching success, and mortality. Here we extend the application of ¹H NMR-based metabolomics in environmental toxicology by adding a suite of metabolic endpoints to the Japanese medaka (Oryzias latipes) embryo assay, with the goal to provide more sensitive, specific and unbiased biomarkers of toxicity. Medaka were exposed throughout embryogenesis to five concentrations of trichloroethylene (TCE; 0, 8.76, 21.9, 43.8, 87.6, 175 mg/L) and the relative sensitivities of the traditional and metabolomic endpoints compared. While the no-observable-adverse-effect-level for hatching success, the most sensitive traditional indicator, was 164 mg/L TCE, metabolic perturbations were detected at all exposure concentrations. Principal components analysis (PCA) highlighted a dose-response relationship between the NMR spectra of medaka extracts. In addition, 12 metabolites that exhibited highly significant dose-response relationships were identified, which indicated an energetic cost to TCE exposure. Next, embryos were exposed to 0, 0.88, 8.76 mg/L TCE and sampled on each of the 8 days of development. Projections of 66 two-dimensional J-resolved NMR spectra were obtained, and PCA revealed developmental metabolic trajectories that characterized the basal and TCE-perturbed changes in the entire NMR-visible metabolome throughout embryogenesis. Although no significant increases in mortality, gross deformity or developmental retardation were observed relative to the control group, TCE-induced metabolic perturbations were observed on day 8. In conclusion, these results support the continued development of NMR-based metabolomics as a rapid and reproducible tool for biomarker discovery and environmental risk assessment.     

Antioxidant and antiapoptotic effects of proanthocyanidin and ginkgo biloba extract against doxorubicin‐induced cardiac injury in rats

Grape seed proanthocyanidins (GSPE) and ginkgo biloba extract (EGb761) are considered to have protective effects against several diseases. The cardiotoxicity of doxorubicin (DOX) has been reported to be associated with oxidative damage. This study was conducted to evaluate the cardioprotective effects of GSPE and EGb761 against DOX‐induced heart injury in rats. DOX was administered as a single i.p. dose (20 mg kg^–1) to adult male rats. DOX‐intoxicated rats were orally administered GSPE (200 mg kg^–1 day^–1) or EGb761 (100 mg kg^–1 day^–1) for 15 consecutive days, starting 10 days prior DOX injection. DOX‐induced cardiotoxicity was evidenced by a significant increase in serum aspartate transaminase (AST), creatine phosphokinase isoenzyme (CK‐MB), lactate dehydrogenase (LDH), total cholesterol (TC) and triglyceride (TG) activities and levels. Increased oxidative damage was expressed by the depletion of cardiac reduced glutathione (GSH), elevation of cardiac total antioxidant (TAO) level and accumulation of the lipid peroxidation product, malondialdehyde (MDA). Significant rises in cardiac tumour necrosis factor‐alpha (TNF‐α) and caspase‐3 levels were noticed in DOX‐intoxicated rats. These changes were ameliorated in the GSPE and EGb761‐treated groups. Histopathological analysis confirmed the cardioprotective effects of GSPE and EGb761. In conclusion, GSPE and EGb761 mediate their protective effect against DOX‐induced cardiac injury through antioxidant, anti‐inflammatory and antiapoptotic mechanisms. Copyright © 2012 John Wiley & Sons, Ltd.     

<Superscript>1</Superscript>H NMR-based metabolomics combined with HPLC-PDA-MS-SPE-NMR for investigation of standardized <Emphasis Type="Italic">Ginkgo biloba</Emphasis> preparations

Commercial preparations of Ginkgo biloba are very complex mixtures prepared from raw leaf extracts by a series of extraction and prepurification steps. The pharmacological activity is attributed to a number of flavonoid glycosides and unique terpene trilactones (TTLs), with largely uncharacterized pharmacological profiles on targets involved in neurological disorders. It is therefore important to complement existing targeted analytical methods for analysis of Ginkgo biloba preparations with alternative technology platforms for their comprehensive and global characterization. In this work, ¹H NMR-based metabolomics and hyphenation of high-performance liquid chromatography, photo-diode array detection, mass spectrometry, solid-phase extraction, and nuclear magnetic resonance spectroscopy (HPLC-PDA-MS-SPE-NMR) were used for investigation of 16 commercially available preparations of Ginkgo biloba. The standardized extracts originated from Denmark, Italy, Sweden, and United Kingdom, and the results show that ¹H NMR spectra allow simultaneous assessment of the content as well as identity of flavonoid glycosides and TTLs based on a very simple sample-preparation procedure consisting of extraction, evaporation and reconstitution in acetone-d ₆. Unexpected or unwanted extract constituents were also easily identified in the ¹H NMR spectra, which contrasts traditional methods that depend on UV absorption or MS ionizability and usually require availability of reference standards. Automated integration of ¹H NMR spectral segments (buckets or bins of 0.02 ppm width) provides relative distribution plots of TTLs based on their H-12 resonances. The present study shows that ¹H NMR-based metabolomics is an attractive method for non-selective and comprehensive analysis of Ginkgo extracts.     

Influence of ethanol concentration of extraction solvent on metabolite profiling for Salviae Miltiorrhizae Radix et Rhizoma extract by 1H NMR spectroscopy and multivariate data analysis

Salviae Miltiorrhizae Radix et Rhizoma (Danshen in China) and its related preparations are widely used in clinical practice due to its high medicinal value. In recent years, ¹H NMR technology has made great progress and demonstrated its unique advantages in the field of botanical metabolomics. In this study, ¹H NMR-based metabolomics was used to investigate the dissolution of various metabolites in Danshen as a function of ethanol concentration. ¹H NMR spectroscopy of Danshen extract identified 28 metabolites including 6 sugars, 11 amino acids, 3 organic acids, 4 salvianolic acids, and 4 tanshinones. Multivariate statistical analysis was used to classify and compare various Danshen extracts. PCA and HCA were used to obtain a global overview of the similarity in the samples and two-class OPLS-DA models were established for identifying characteristic metabolites. Then, ¹H-qNMR method was used to estimate the concentration of 22 metabolites, which is helpful to further describe the changes in metabolite ratios of various Danshen extracts. The result of this study laid the foundation for further biological activity research, and also provided an important reference for subsequent process research and quality control of Danshen related preparations.     

Apelin-13 attenuates cisplatin-induced cardiotoxicity through inhibition of ROS-mediated DNA damage and regulation of MAPKs and AKT pathways

Platinum-based chemotherapy represents one of the most effective ways in combating human cancers. However, the cardiotoxicity subsequent severely limited its clinical application. Increased evidences indicate that oxidative stress plays a crucial role in the pathological process of platinum-induced cardiotoxicity. It is reported that apelin-13 a bioactive peptide has the scavenging capacity of free radical, and it has the potential to regulate the cardiovascular system. Hence, the potential of apelin-13 to antagonize cisplatin-induced cardiotoxicity was evaluated in H9c2 rat myocardial cells in vitro and in C57 mice in vivo. The results showed that cisplatin indeed caused DNA damage in H9c2 cells by promoting the accumulation of intracellular reactive oxygen species (ROS) and superoxide anion, which led to cell apoptosis and resulted in overt cardiotoxicity. However, apelin-13 pre-treatment effectively attenuated the cisplatin-induced ROS and superoxide anion generation, inhibited DNA damage, and suppressed the PARP cleavage and caspases activation. Further investigation revealed that apelin-13 blocked cisplatin-induced H9c2 cells apoptosis involving the regulation of MAPKs and PI3K/Akt signaling pathway. Importantly, apelin-13 co-treatment also significantly attenuated cisplatin-induced cardiotoxicity in vivo by inhibiting myocardial cells apoptosis and improving angiogenesis in mice heart. Taken together, our results suggest that the use of apelin-13 may be an effective strategy for antagonizing the cardiotoxicity-induced by platinum-based chemotherapy.     

Improved classification accuracy in 1- and 2-dimensional NMR metabolomics data using the variance stabilising generalised logarithm transformation

Background  

Classifying nuclear magnetic resonance (NMR) spectra is a crucial step in many metabolomics experiments. Since several multivariate classification techniques depend upon the variance of the data, it is important to first minimise any contribution from unwanted technical variance arising from sample preparation and analytical measurements, and thereby maximise any contribution from wanted biological variance between different classes. The generalised logarithm (glog) transform was developed to stabilise the variance in DNA microarray datasets, but has rarely been applied to metabolomics data. In particular, it has not been rigorously evaluated against other scaling techniques used in metabolomics, nor tested on all forms of NMR spectra including 1-dimensional (1D) ¹H, projections of 2D ¹H, ¹H J-resolved (pJRES), and intact 2D J-resolved (JRES).     

Quantitative <Superscript>1</Superscript>H NMR metabolomics reveals extensive metabolic reprogramming of primary and secondary metabolism in elicitor-treated opium poppy cell cultures

Background  

Opium poppy (Papaver somniferum) produces a diverse array of bioactive benzylisoquinoline alkaloids and has emerged as a model system to study plant alkaloid metabolism. The plant is cultivated as the only commercial source of the narcotic analgesics morphine and codeine, but also produces many other alkaloids including the antimicrobial agent sanguinarine. Modulations in plant secondary metabolism as a result of environmental perturbations are often associated with the altered regulation of other metabolic pathways. As a key component of our functional genomics platform for opium poppy we have used proton nuclear magnetic resonance (¹H NMR) metabolomics to investigate the interplay between primary and secondary metabolism in cultured opium poppy cells treated with a fungal elicitor.     

Beneficial effects of angiotensin II receptor blocker,olmesartan, in limiting the cardiotoxic effect of daunorubicin in rats

Abstract

The aim was to evaluate the role of the combination of olmesartan, an angiotensin II (Ang II) receptor blocker (ARB), with daunorubicin (DNR) in reducing cardiac toxicity in rats. DNR was administered at a dose of 3 mg/kg/day every other day for 12 days. Olmesartan was administered orally every day for 12 days. Rats treated with DNR alone showed cardiac toxicity as evidenced by worsening cardiac function, elevation of malondialdehyde level in heart tissue and decreased in the level of total glutathione peroxidase activity; treatment with ARB reversed these changes. Furthermore, ARB treatment down-regulated matrix metalloproteinase-2 expression, myocardial expression of Ang II, attenuated the increased protein expressions of p67^phox and Nox4 and reduced oxidative stress-induced DNA damage evaluated by expression of 8-hydroxydeoxyguanosine. In conclusion, the result demonstrated that Ang II and oxidative stress play a key role in anthracycline-induced cardiotoxicity and that treatment with ARB will be beneficial against DNR-induced cardiotoxicity.     

Validation of Metabolic Alterations in Microscale Cell Culture Lysates Using Hydrophilic Interaction Liquid Chromatography (HILIC)-Tandem Mass Spectrometry-Based Metabolomics

By standard convention, in order to increase the efficacy of metabolite detection from cell culture lysates, metabolite extracts from a large quantity of cells are utilized for multiple reaction monitoring-based metabolomic studies. Metabolomics from a small number of cell extracts offers a potential economical alternative to increased cell numbers, in turn increasing the utility of cell culture-based metabolomics. However, the effect of reduced cell numbers on targeted metabolomic profiling is relatively unstudied. Considering the limited knowledge available of the feasibility and accuracy of microscale cell culture metabolomics, the present study analyzes differences in metabolomic profiles of different cell numbers of three pancreatic cancer cell lines. Specifically, it examines the effects of reduced cell numbers on metabolite profiles by obtaining extracts either directly from microscale culture plates or through serial dilution of increased numbers of cellular metabolite extracts. Our results indicate reduced cell numbers only modestly affect the number of metabolites detected (93% of metabolites detected in cell numbers as low as 10⁴ cells and 97% for 10⁵ cells), independent of the method used to obtain the cells. However, metabolite peak intensities were differentially affected by the reduced cell numbers, with some peak intensities inversely proportional to the cell numbers. To help eliminate such potential inverse relationships, peak intensities for increased cell numbers were excluded from the comparative analysis. Overall, metabolite profiles from microscale culture plates were observed to differ from the serial dilution samples, which may be attributable to the medium-to-cell-number ratios. Finally, findings identify perturbations in metabolomic profiling for cellular extracts from reduced cell numbers, which offer future applications in microscale metabolomic evaluations.     

Protective effect of vitamin B6 against doxorubicin-induced cardiotoxicity by modulating NHE1 expression

Doxorubicin (DOX) has been used to treat various types of cancer, but its application is limited due to its heart toxicity as well as other drawbacks. Chronic inhibition of Na⁺/H⁺ exchanger (NHE1) reduces heart failure and reduces the production of reactive oxygen species (ROS); vitamin B6 (VitB₆) has been demonstrated to have a crucial role in antioxidant mechanism. So, this study was designed to explore the effect of VitB₆ supplement on the DOX-induced cardiotoxicity and to imply whether NHE1 is involved. Ultrasonic cardiogram analysis revealed that VitB₆ supplement could alleviate DOX-induced cardiotoxicity; hematoxylin and eosin (HE) and Masson's staining further confirmed this effect. Furthermore, VitB₆ supplement exhibited significant antioxidative stress and antiapoptosis effect, which was evidenced by decreased serum malondialdehyde (MDA) content and increased serum superoxide dismutase (SOD) content, and decreased Bcl-2-associated X protein/B-cell lymphoma-2 ratio, respectively. Collectively, VitB₆ supplement may exert antioxidative and antiapoptosis effects to improve cardiac function by decreasing NHE1 expression and improve DOX-induced cardiotoxicity.     

Evaluation of the potential cardioprotective activity of some Saudi plants against doxorubicin toxicity

Doxorubicin (DOX) is an anthracycline antibiotic widely used as a chemotherapeutic agent in the treatment of several tumours. However, its cardiac toxicity limits its use at maximum therapeutic doses. Most studies implicated increased oxidative stress as the major determinant of DOX cardiotoxicity. The local Saudi flora is very rich in a variety of plants of quite known folkloric or traditional medicinal uses. Tribulus macropterus Boiss., Olea europaea L. subsp. africana (Mill.) P. S. Green, Tamarix aphylla (L.) H. Karst., Cynomorium coccineum L., Cordia myxa L., Calligonum comosum L' Hér, and Withania somnifera (L.) Dunal are Saudi plants known to have antioxidant activities. The aim of the current study was to explore the potential protective effects of methanolic extracts of these seven Saudi plants against DOX-induced cardiotoxicity in rats. Two plants showed promising cardioprotective potential in the order Calligonum comosum > Cordia myxa. The two plant extracts showed potent in vitro radical scavenging and antioxidant properties. They significantly protected against DOX-induced alterations in cardiac oxidative stress markers (GSH and MDA) and cardiac serum markers (CK-MB and LDH activities). Additionally, histopathological examination indicated a protection against DOX-induced cardiotoxicity. In conclusion, C. comosum and C. myxa exerted protective activity against DOX-induced cardiotoxicity, which is, at least partly, due to their antioxidant effect.     

Induction of caspase-independent apoptosis in H9c2 cardiomyocytes by adriamycin treatment

The cardiotoxicity of adriamycin limits its clinical use as a powerful drug for solid tumors and malignant hematological disease. Although the precise mechanism by which it causes cardiac damage is not yet known, it has been suggested that apoptosis is the principal process in adriamycin-induced cardiomyopathy, which involves DNA fragmentation, cytochrome C release, and caspase activation. However, there has been no direct evidence for the critical involvement of caspase-3 in adriamycin-induced apoptosis. To determine the requirements for the activation of caspase-3 in adriamycin-treated cardiac cells, the effect of a caspase inhibitor on the survival of and apoptotic changes in H9c2 cells was examined. Exposure of H9c2 cells to adriamycin resulted in a time- and dose-dependent cell death, and the cleavage of pro-caspase-3 and of the nuclear protein poly (ADP-ribose) polymerase (PARP). However, neither the reduction of cell viability nor the characteristic morphological changes induced by adriamycin were prevented by pretreatment with the general caspase inhibitor z-VAD.FMK. In contrast, caspase inhibition effectively blocked the apoptosis induced by H₂O₂ in H9c2 cells, as determined by an MTT assay or microscopy. We also observed that p53 expression was increased by adriamycin, and this increase was not affected by the inhibition of caspase activity, suggesting a role for p53 in adriamycin-induced caspase-independent apoptosis in cardiac toxicity. (Mol Cell Biochem 270: 13–19, 2005)These authors contributed equally to this work     

Mass appeal: metabolite identification in mass spectrometry-focused untargeted metabolomics

¹H nuclear magnetic resonance (¹H NMR)-based metabolomics was utilized to elucidate the earthworm sub-lethal toxicity after exposure to the persistent environmental contaminant phenanthrene. Earthworms were exposed to 0.05, 0.2 and 0.4 mg/cm² of phenanthrene [which correspond to 1/32nd to 1/4th of the 48-h LC₅₀ (concentration that causes 50 % mortality), respectively] via contact tests over 1, 2 and 3 days of dermal contact. ¹H NMR-based metabolomic analysis of the polar and non-polar fractions of the earthworm tissue extracts revealed heightened Eisenia fetida toxic responses with both longer exposure times and higher phenanthrene concentrations. Principal component analysis (PCA) of the polar fraction showed significant separation between control and exposed earthworms along PC1 for all phenanthrene concentrations on each day. The PCA of the non-polar fraction showed significant separation between the controls and exposed earthworms for only the first day of exposure. These results suggested that alanine, glutamate, maltose, and fatty acids were potential indicators of phenanthrene exposure. Interruption in energy production due to a deactivation of the succinate dehydrogenase enzyme in the Krebs cycle was also postulated in exposed earthworms. Cross-validated partial least squares-regression models showed that the polar metabolic profile of E. fetida was weakly but significantly correlated to phenanthrene exposure concentrations after day 1 and day 2 of exposure. Overall, this study indicates that with longer exposures, contact time becomes more important than concentration in discriminating between control and exposed earthworms. This study also shows that NMR-based metabolomics has promise as a powerful ecotoxicological tool for elucidating the mode of toxicity of contaminants.     

Prevention of cardiotoxicity of aflatoxin B1 via dietary supplementation of papaya fruit extracts in rats

The aim of the current study was to evaluate the cardioprotective ability of water (WE) and ethanolic (EE) papaya fruits extracts against cardiotoxicity induced by aflatoxin B₁ (AFB₁) in rats. Forty two female Sprague–Dawley rats were divided into six treatment groups and treated orally for 2 weeks as follow: control group, the group treated with WE (250 mg/kg b.w), the group treated with EE (250 mg/kg b.w), the group treated orally with AFB₁ (17 μg/kg b.w) and the groups treated orally with AFB₁ plus WE or EE. The results indicated that treatment with AFB₁ resulted in oxidative stress in the heart manifested by the marked increase in cardiac malondialdehyde and calcium levels accompanied with a significant decrease in cardiac total antioxidant capacity. Serum nitric oxide and sodium levels, lactate dehydrogenase and creatine kinase isoenzyme activities were significantly increased, whereas, cardiac Na⁺/K⁺-ATPase activity and serum potassium were insignificantly affected. Supplementation with WE or EE effectively ameliorated most of the changes induced by AFB₁. It could be concluded that both extracts attenuated the oxidative stress induced in heart tissue by AFB₁ and WE was more pronounced due to the higher total phenolic contents than in the EE.     

Creatine Kinase-Overexpression Improves Myocardial Energetics,Contractile Dysfunction and Survival in Murine Doxorubicin Cardiotoxicity

Doxorubicin (DOX) is a commonly used life-saving antineoplastic agent that also causes dose-dependent cardiotoxicity. Because ATP is absolutely required to sustain normal cardiac contractile function and because impaired ATP synthesis through creatine kinase (CK), the primary myocardial energy reserve reaction, may contribute to contractile dysfunction in heart failure, we hypothesized that impaired CK energy metabolism contributes to DOX-induced cardiotoxicity. We therefore overexpressed the myofibrillar isoform of CK (CK-M) in the heart and determined the energetic, contractile and survival effects of CK-M following weekly DOX (5mg/kg) administration using in vivo ³¹P MRS and ¹H MRI. In control animals, in vivo cardiac energetics were reduced at 7 weeks of DOX protocol and this was followed by a mild but significant reduction in left ventricular ejection fraction (EF) at 8 weeks of DOX, as compared to baseline. At baseline, CK-M overexpression (CK-M-OE) increased rates of ATP synthesis through cardiac CK (CK flux) but did not affect contractile function. Following DOX however, CK-M-OE hearts had better preservation of creatine phosphate and higher CK flux and higher EF as compared to control DOX hearts. Survival after DOX administration was significantly better in CK-M-OE than in control animals (p<0.02). Thus CK-M-OE attenuates the early decline in myocardial high-energy phosphates and contractile function caused by chronic DOX administration and increases survival. These findings suggest that CK impairment plays an energetic and functional role in this DOX-cardiotoxicity model and suggests that metabolic strategies, particularly those targeting CK, offer an appealing new strategy for limiting DOX-associated cardiotoxicity.     

MicroRNA‐129‐1‐3p protects cardiomyocytes from pirarubicin‐induced apoptosis by down‐regulating the GRIN2D‐mediated Ca2+ signalling pathway

Pirarubicin (THP), an anthracycline anticancer drug, is a first‐line therapy for various solid tumours and haematologic malignancies. However, THP can cause dose‐dependent cumulative cardiac damage, which limits its therapeutic window. The mechanisms underlying THP cardiotoxicity are not fully understood. We previously showed that MiR‐129‐1‐3p, a potential biomarker of cardiovascular disease, was down‐regulated in a rat model of THP‐induced cardiac injury. In this study, we used Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) pathway enrichment analyses to determine the pathways affected by miR‐129‐1‐3p expression. The results linked miR‐129‐1‐3p to the Ca²⁺ signalling pathway. TargetScan database screening identified a tentative miR‐129‐1‐3p‐binding site at the 3′‐UTR of GRIN2D, a subunit of the N‐methyl‐D‐aspartate receptor calcium channel. A luciferase reporter assay confirmed that miR‐129‐1‐3p directly regulates GRIN2D. In H9C2 (rat) and HL‐1 (mouse) cardiomyocytes, THP caused oxidative stress, calcium overload and apoptotic cell death. These THP‐induced changes were ameliorated by miR‐129‐1‐3p overexpression, but exacerbated by miR‐129‐1‐3p knock‐down. In addition, miR‐129‐1‐3p overexpression in cardiomyocytes prevented THP‐induced changes in the expression of proteins that are either key components of Ca²⁺ signalling or important regulators of intracellular calcium trafficking/balance in cardiomyocytes including GRIN2D, CALM1, CaMKⅡδ, RyR2‐pS2814, SERCA2a and NCX1. Together, these bioinformatics and cell‐based experiments indicate that miR‐129‐1‐3p protects against THP‐induced cardiomyocyte apoptosis by down‐regulating the GRIN2D‐mediated Ca²⁺ pathway. Our results reveal a novel mechanism underlying the pathogenesis of THP‐induced cardiotoxicity. The miR‐129‐1‐3p/Ca²⁺ signalling pathway could serve as a target for the development of new cardioprotective agents to control THP‐induced cardiotoxicity.     

Melatonin and metformin ameliorated trastuzumab-induced cardiotoxicity through the modulation of mitochondrial function and dynamics without reducing its anticancer efficacy

Trastuzumab has an impressive level of efficacy as regards antineoplasticity, however it can cause serious cardiotoxic side effects manifested by impaired cardiac contractile function. Although several pharmacological interventions, including melatonin and metformin, have been reported to protect against various cardiovascular diseases, their potential roles in trastuzumab-induced cardiotoxicity remain elusive. We hypothesized that either melatonin or metformin co-treatment effectively attenuates trastuzumab-mediated cardiotoxicity through attenuating the impaired mitochondrial function and mitochondrial dynamics. Male Wistar rats were divided into control (normal saline, n = 8) and trastuzumab group (4 mg/kg/day for 7 days, n = 24). Rats in the trastuzumab group were subdivided into 3 interventional groups (n = 8/group), and normal saline, or melatonin (10 mg/kg/day), or metformin (250 mg/kg/day) were orally administered for 7 consecutive days. Cardiac parameters were determined, and biochemical investigations were carried out on blood and heart tissues. Trastuzumab induced left ventricular (LV) dysfunction by increasing oxidative stress, inflammation, and apoptosis. It also impaired cardiac mitochondrial function, dynamics, and autophagy. Treatment with either melatonin or metformin equally attenuated trastuzumab-induced cardiac injury, indicated by a marked reduction in inflammation, oxidative damage, cardiac mitochondrial injury, mitochondrial dynamic imbalance, autophagy dysregulation, and apoptosis, leading to improved LV function, as demonstrated by increased LV ejection fraction. Melatonin and metformin conferred equal levels of cardioprotection against trastuzumab-induced cardiotoxicity, which may provide novel and promising approaches for management of cardiotoxicity induced by trastuzumab.     

Loss of endothelial cell-specific autophagy-related protein 7 exacerbates doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is an effective, broad-spectrum antineoplastic agent with serious cardiotoxic side effects, which may lead to the development of heart failure. Current strategies to diagnose, prevent, and treat DOX-induced cardiotoxicity (DIC) are inadequate. Recent evidence has linked the dysregulation and destruction of the vascular endothelium to the development of DIC. Autophagy is a conserved pro-survival mechanism that recycles and removes damaged sub-cellular components. Autophagy-related protein 7 (ATG7) catalyzes autophagosome formation, a critical step in autophagy. In this study, we used endothelial cell-specific Atg7 knockout (EC-Atg7^?/?) mice to characterize the role of endothelial cell-specific autophagy in DIC. DOX-treated EC-Atg7^?/? mice showed reduced survival and a greater decline in cardiac function compared to wild-type controls. Histological assessments revealed increased cardiac fibrosis in DOX-treated EC-Atg7^?/? mice. Furthermore, DOX-treated EC-Atg7^?/? mice had elevated serum levels of creatine kinase-myocardial band, a biomarker for cardiac damage. Thus, the lack of EC-specific autophagy exacerbated DIC. Future studies on the relationship between EC-specific autophagy and DIC could establish the importance of endothelium protection in preventing DIC.     

Proposed reporting requirements for the description of NMR-based metabolomics experiments

The amount of data generated by NMR-based metabolomic experiments is increasing rapidly. Furthermore, diverse techniques increase the need for informative and comprehensive meta-data. These factors present a challenge in the dissemination, interpretation, reviewing and comparison of experimental results using this technology. Thus, there is a strong case for unification and standardisation of the data representation for both academia and industry. Here, a systems analysis of an NMR-based metabolomics experiment is presented in order to reveal the reporting requirements. An in-depth analysis of the NMR component of a metabolomics experiment has been produced, and a first round of data standard development completed. This has focussed on both one- and two-dimensional ¹H NMR experiments, but is also applicable to higher dimensions and other nuclei. We also report the modelling of this schema using Unified Modelling Language (UML), and have extended this to a proof-of-concept implementation of the standard as an XML schema.     

Harpagophytum procumbens Prevents Oxidative Stress and Loss of Cell Viability In Vitro

Harpagophytum procumbens, popularly known as devil’s claw, is a plant commonly used in the treatment of diseases of inflammatory origin. The anti-inflammatory effects of H. procumbens have been studied; however, the mechanism of action is not elucidated. It is known that excess of reactive oxygen and nitrogen species may contribute to increasing tissue damage due to inflammation. In the present study, we examined the effects of H. procumbens infusion, crude extract and fractions on lipid peroxidation (brain homogenates) induced by different pro-oxidants (Fe²⁺ or sodium nitroprusside) and the effects of ethyl acetate fraction (rich in phenolic compounds) on antioxidant defenses (catalase activity and thiol levels) and cell damage (brain cortical slices) induced by different pro-oxidants. All tested extracts of H. procumbens inhibited lipid peroxidation in a concentration-dependent manner. Furthermore, the ethyl acetate fraction had the highest antioxidant effects either by decreasing lipid peroxidation and cellular damage or restoring thiols levels and catalase activity. Taken together, our results showed that H. procumbens acts either by preventing oxidative stress or loss of cell viability. Thus, the previously reported anti-inflammatory effect of H. procumbens could also be attributed to its antioxidant activity.