Metabolomics As a Tool for the Characterization of Drug-Resistant Epilepsy.

PURPOSE: Drug resistance is a critical issue in the treatment of epilepsy, contributing to clinical emergencies and increasing both serious social and economic burdens on the health system. The wide variety of potential drug combinations followed by often failed consecutive attempts to match drugs to an individual patient may mean that this treatment stage may last for years with suboptimal benefit to the patient. Given these challenges, it is valuable to explore the availability of new methodologies able to shorten the period of determining a rationale pharmacologic treatment. Metabolomics could provide such a tool to investigate possible markers of drug resistance in subjects with epilepsy. METHODS: Blood samples were collected from (1) controls (C) (n = 35), (2) patients with epilepsy "responder" (R) (n = 18), and (3) patients with epilepsy "non-responder" (NR) (n = 17) to the drug therapy. The samples were analyzed using nuclear magnetic resonance spectroscopy, followed by multivariate statistical analysis. KEY FINDINGS: A different metabolic profile based on metabolomics analysis of the serum was observed between C and patients with epilepsy and also between R and NR patients. It was possible to identify the discriminant metabolites for the three classes under investigation. Serum from patients with epilepsy were characterized by increased levels of 3-OH-butyrate, 2-OH-valerate, 2-OH-butyrate, acetoacetate, acetone, acetate, choline, alanine, glutamate, scyllo-inositol (C  R > NR). SIGNIFICANCE: In conclusion, metabolomics may represent an important tool for discovery of differences between subjects affected by epilepsy responding or resistant to therapies and for the study of its pathophysiology, optimizing the therapeutic resources and the quality of life of patients

KniMet: a pipeline for the processing of chromatography-mass spectrometry metabolomics data.

INTRODUCTION: Data processing is one of the biggest problems in metabolomics, given the high number of samples analyzed and the need of multiple software packages for each step of the processing workflow. OBJECTIVES: Merge in the same platform the steps required for metabolomics data processing. METHODS: KniMet is a workflow for the processing of mass spectrometry-metabolomics data based on the KNIME Analytics platform. RESULTS: The approach includes key steps to follow in metabolomics data processing: feature filtering, missing value imputation, normalization, batch correction and annotation. CONCLUSION: KniMet provides the user with a local, modular and customizable workflow for the processing of both GC-MS and LC-MS open profiling data

(1)H-NMR analysis provides a metabolomic profile of patients with multiple sclerosis

OBJECTIVE: To investigate the metabolomic profiles of patients with multiple sclerosis (MS) and to define the metabolic pathways potentially related to MS pathogenesis. METHODS: Plasma samples from 73 patients with MS (therapy-free for at least 90 days) and 88 healthy controls (HC) were analyzed by (1)H-NMR spectroscopy. Data analysis was conducted with principal components analysis followed by a supervised analysis (orthogonal partial least squares discriminant analysis [OPLS-DA]). The metabolites were identified and quantified using Chenomx software, and the receiver operating characteristic (ROC) curves were calculated. RESULTS: The model obtained with the OPLS-DA identified predictive metabolic differences between the patients with MS and HC (R2X = 0.615, R2Y = 0.619, Q2 = 0.476; p < 0.001). The differential metabolites included glucose, 5-OH-tryptophan, and tryptophan, which were lower in the MS group, and 3-OH-butyrate, acetoacetate, acetone, alanine, and choline, which were higher in the MS group. The suitability of the model was evaluated using an external set of samples. The values returned by the model were used to build the corresponding ROC curve (area under the curve of 0.98). CONCLUSION: NMR metabolomic analysis was able to discriminate different metabolic profiles in patients with MS compared with HC. With the exception of choline, the main metabolic changes could be connected to 2 different metabolic pathways: tryptophan metabolism and energy metabolism. Metabolomics appears to represent a promising noninvasive approach for the study of M

Rapid generation of chromosome-specific alphoid DNA probes using the polymerase chain reaction

Non-isotopic in situ hybridization of chromosome-specific alphoid DNA probes has become a potent tool in the study of numerical aberrations of specific human chromosomes at all stages of the cell cycle. In this paper, we describe approaches for the rapid generation of such probes using the polymerase chain reaction (PCR), and demonstrate their chromosome specificity by fluorescence in situ hybridization to normal human metaphase spreads and interphase nuclei. Oligonucleotide primers for conserved regions of the alpha satellite monomer were used to generate chromosome-specific DNA probes from somatic hybrid cells containing various human chromosomes, and from DNA libraries from sorted human chromosomes. Oligonucleotide primers for chromosome-specific regions of the alpha satellite monomer were used to generate specific DNA probes for the pericentromeric heterochromatin of human chromosomes 1, 6, 7, 17 and X directly from human genomic DNA

The rat dorsal column nuclei contain a region homologous to the human Locus K

Locus K is a newly identified region within the territory of the human nucleus cuneatus that shares neurochemical and histological features with protopathic second order sensory nuclei (Del Fiacco et al., 2013; Serra et al., 2013; SIAI 2014). This work is aimed at examining the rat dorsal column nuclei in order to ascertain whether a structure homologous to the human Locus K occurs in the rat brain. Rat brainstem sections were observed by means of ABC and fluorescence immunohistochemistry for neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP), Kluver-Barrera and Nissl staining. Results of the peptide immunoreactive structures in the rat dorsal column nuclei are in general good agreement with findings in previous studies (Hoeflinger et al., 1993). However, at caudalmost levels of the complex, in the territory of the cuneate fascicle and dorsal to the caudal pole of the cuneate nucleus, a small column of gray matter area can be identified that contains a dense plexus of varicose labelled nerve fibres. The observed discrete region has never distinctly described beforehand. Both its position and aspect at neuropeptide-immunoreactivity resemble those of the Locus K we detected in the human dorsal column nuclei, allowing the possibility that it represents the its homologous nucleus in the rat brain. Work funded by Fondazione Banco di Sardegna

Analysis and applications of respiratory surface EMG:report of a round table meeting

Surface electromyography (sEMG) can be used to measure the electrical activity of the respiratory muscles. The possible applications of sEMG span from patients suffering from acute respiratory failure to patients receiving chronic home mechanical ventilation, to evaluate muscle function, titrate ventilatory support and guide treatment. However, sEMG is mainly used as a monitoring tool for research and its use in clinical practice is still limited—in part due to a lack of standardization and transparent reporting. During this round table meeting, recommendations on data acquisition, processing, interpretation, and potential clinical applications of respiratory sEMG were discussed. This paper informs the clinical researcher interested in respiratory muscle monitoring about the current state of the art on sEMG, knowledge gaps and potential future applications for patients with respiratory failure.</p

Transient receptor potential vanilloid type 1 (TRPV1) and neuropeptides in the dorsal root ganglia and spinal cord in a rat model of Bortezomib-induced neuropathy

Bortezomib (BTZ) is an effective antineoplastic drug that acts by inhibiting the ubiquitin-proteasome cellular pathways. In clinical practice, its chronic administration triggers a significant neurotoxicity, which has been associated with impairment of Aβ, Aδ, and C type primary afferent fibers, though the mechanism underlying its harmful effects remains still to be fully clarified. In order to mimic the clinical use of the drug, we have recently designed an experimental model based on the use of 0,20 mg/kg drug concentration for 8 weeks followed by a follow-up period of 4 weeks. We have previously shown that, in these conditions, a hallmark of neurotoxicity is represented by a small fiber neuropathy, whereas dorsal root ganglia (DRG) neurons did not show any morphological alterations. In order to provide data regarding the mechanism underlying BTZ harmful effects, here we characterize the spinal primary sensory neurons on the basis of their expression of the transient receptor potential vanilloid type-1 (TRPV1) and sensory neuropeptides calcitonin gene-related peptide (CGRP) and substance P (SP). In fact, TRPV1 is expressed by sensory neurons where it functions as a molecular integrator for nociception. Its activation causes depolarisation leading to burning pain and release of CGRP and SP which, in turn, activate their effector cell receptors and enhance the sensitization of nociceptors. With this aim, lumbar DRG and spinal cord of BTZ-treated model rats were processed for avidine-biotin-peroxidase complex or fluorescence immunohistochemistry. In the DRG, the immunolabelling for TRPV1 revealed a subpopulation of predominantly small- to medium-sized neurons which appeared more extensive in BTZ-treated rats. Centrally, TRPV1-LI labelled fiber tracts and terminal-like elements distributed in laminae I and II of the dorsal horn where they appeared widely codistributed with both CGRP-LI and SP-LI. With the exception of a slight more intense TRPV1 staining in lamina I of the dorsal horn of BTZ-treated vs control rats, no clear-cut differences in the distribution and amount of immunoreactivity for the three markers could be observed

Effect of acute administration of dietary Pistacia lentiscus L. essential oil on the ischemia-reperfusion-induced changes in rat frontal cortex and plasma

In this study Pistacia lentiscus L. essential oil (E.O.), a mixture of terpenes and sesquiterpenes, was tested for its protective effects in cerebral ischemia/reperfusion-induced injury in Wistar rat frontal cortex and plasma. Cerebral ischemia was produced by a 20 min bilateral common carotid artery occlusion followed by 30 min reperfusion. Pistacia lentiscus L. essential oil (E.O.) (200 mg/0, 45 ml of sunflower oil as vehicle) was administered via gavage 6 hours prior to ischemia. Rats were randomly assigned to four groups, ischemic/reperfused (I/R) and sham-operated rats treated with the vehicle or with E.O.. Different brain areas were analysed for fatty acid changes and expression of the enzyme cyclooxygenase-2 (COX-2). Ischemia/reperfusion triggered in frontal cortex a decrease of docosahexaenoic acid (DHA), the membrane highly polyunsaturated fatty acid (HPUFA) most susceptible to oxidation. Pre-treatment with E.O. prevented this change and led further to decreased levels of COX-2, as assessed by Western Blot. In plasma of ischemic/reperfused rats, E.O. administration increased both the DHA-to-eicosapentaenoic acid (EPA) ratio and levels of the endocannabinoid congeners palmytoylethanolamide (PEA) and oleoylethanolamide (OEA). The results obtained suggest that ischemia/reperfusion triggers a cerebral insult sufficient to cause a a region specific lipid peroxidation as evidenced by the detectable, significant decrease in the tissue level of DHA, the most abundant essential fatty acid of neuronal membrane phospholipids. Acute dietary pre-treatment with E.O. triggers modifications both in the frontal cortex, where COX-2 expression decreases and the decrease of DHA is apparently prevented, and in plasma, where PEA and OEA levels increase. We suggest that the activity of PEA and OEA, as endogenous ligands of the peroxisome proliferator-activated receptor (PPAR)-alpha, by inducing the peroxisomal beta oxidation, may explain the observed increase in the DHA/EPA ratio. The latter, in fact, might account for an increased metabolism of n-3 aimed at restoring DHA within damaged brain tissue. The possibility that changes in fatty acid metabolism and plasmatic availability of PEA and OEA are correlated events represents an issue worth future investigations

Dietary essential oil components in the prevention of hypoperfusion/reperfusion-induced tissue damage in the rat cerebral cortex

To extend our previous observations on the beneficial effect of dietary Pistacia lentiscus L. essential oil during cerebral bilateral common carotid artery occlusioninduced injury, we evaluated the activity of one of its major components, beta-caryophyllene (BCP), already known to possess peculiar biological activities, in Wistar rat cerebral cortex. Cerebral hypoperfusion was produced by a 30 min bilateral common carotid artery occlusion followed by 60 min reperfusion (BCCAO/R). Animals were starved for 12 hours before surgery and, 6 hours prior to hypoperfusion, BCP (40 mg/kg/0, 45 ml of sunflower oil as vehicle) was administered via gavage. Biological samples of brain tissue, plasma and cerebrospinal fluid (CSF) were examined by HPLC, western blot, gel zymography and immunohistochemistry and analyzed for fatty acids, expression of the enzyme ciclooxygenase-2 (COX-2), CB receptors for endocannabinoids (eCBs), and peroxisome proliferator-activated receptor (PPAR)-alpha and enzymatic activity of matrix-metalloprotease-9 (MMP9). Data obtained indicate that BCP appears to influence the outcome of BCCAO/R cerebral injury by modulating changes in levels of polyunsaturated fatty acids, biosynthesis of eCBs and eCB congeners, expression of CB1 and CB2 receptors, COX-2 protein levels and enzymatic activity of MMP9. Brain tissue response to the hypoperfusion/reperfusion-induced cerebral insult is modulated by dietary administration of BCP, suggesting the possible use of this molecule as nutritional treatment in neuroprevention. Work funded by Fondazione Banco di Sardegna