Current clinical strategy for staging and prognostication of colorectal cancer (CRC) relies mainly upon the TNM or Duke system. This clinicopathological stage is a crude prognostic guide because it ...reflects in part the delay in diagnosis in the case of an advanced cancer and gives little insight into the biological characteristics of the tumor. We hypothesized that global metabolic profiling (metabonomics/metabolomics) of colon mucosae would define metabolic signatures that not only discriminate malignant from normal mucosae, but also could distinguish the anatomical and clinicopathological characteristics of CRC. We applied both high-resolution magic angle spinning nuclear magnetic resonance (HR-MAS NMR) and gas chromatography mass spectrometry (GC/MS) to analyze metabolites in biopsied colorectal tumors and their matched normal mucosae obtained from 31 CRC patients. Orthogonal partial least-squares discriminant analysis (OPLS-DA) models generated from metabolic profiles obtained by both analytical approaches could robustly discriminate normal from malignant samples (Q 2 > 0.50, Receiver Operator Characteristic (ROC) AUC >0.95, using 7-fold cross validation). A total of 31 marker metabolites were identified using the two analytical platforms. The majority of these metabolites were associated with expected metabolic perturbations in CRC including elevated tissue hypoxia, glycolysis, nucleotide biosynthesis, lipid metabolism, inflammation and steroid metabolism. OPLS-DA models showed that the metabolite profiles obtained via HR-MAS NMR could further differentiate colon from rectal cancers (Q 2> 0.60, ROC AUC = 1.00, using 7-fold cross validation). These data suggest that metabolic profiling of CRC mucosae could provide new phenotypic biomarkers for CRC management.
Colorectal cancer (CRC) is the fourth most common cause of death from cancer in the world. The limitations of the currently available methods and biomarkers for CRC management highlight the necessity ...of finding novel markers. Metabonomics can be used to search for potential markers that can provide molecular insight into human CRC. The emergence of two-dimensional gas chromatography time of flight mass spectrometry (GC × GC/TOFMS) has comprehensively enhanced the metabolic space coverage of conventional GC/MS. In this study, a GC × GC/TOFMS was developed for the tissue-based global metabonomic profiling of CRC. A Pegasus GC × GC/TOFMS (Leco Corp., St. Joseph, MI, USA) system comprising an Agilent 7890 GC and Pegasus IV TOFMS was used for this purpose. An Agilent DB-1 (30 m × 250 μm × 0.25 μm) fused silica capillary column and a Restek Rxi®-17 (1 m × 100 μm × 0.10 μm) fused silica capillary column were used as the primary and secondary columns, respectively. The method was applied for global metabonomic profiling of matched CRC and normal tissues (
n
= 63) obtained from 31 CRC patients during surgery. An attempt was also made to compare GC × GC/TOFMS with GC/MS and NMR in similar application. The results showed that the metabotype associated with CRC is distinct from that of normal tissue and led to the identification of chemically diverse marker metabolites. Metabolic pathway mapping suggested deregulation of various biochemical processes such as glycolysis, Krebs cycle, osmoregulation, steroid biosynthesis, eicosanoid biosynthesis, bile acid biosynthesis, lipid, amino acid and nucleotide metabolism.
Fig
Workflow of GCGC/TOFMS metabonomic profiling of human colorectal cancer
The in vitro acetylcholinesterase (AChE) inhibitory potential of the hydroalcoholic extract and of the essential oil from Acorus calamus (AC) rhizomes and that of its major constituents were ...evaluated based on the Ellman's method. GC/MS analysis of the oil revealed that the major constituents were beta-asarone (79.54%) and alpha-asarone (8.47%). The IC50 values were obtained for the hydroalcoholic extract, the essential oil, beta-asarone and alpha-asarone and were 182.31+/-16.78 microg/mL, 10.67+/-0.81 microg/mL, 3.33+/-0.02 microM and 46.38+/-2.69 microM, respectively. Physostigmine was used as standard inhibitor with an IC50 value of 0.28+/-0.015 microM. The experimental observations revealed that the AC essential oil and its constituents have significant AChE inhibitory potential. beta-Asarone, the major phytoconstituent present in the essential oil, showed the maximum inhibitory potential.
Resistance to 5-fluorouracil (5FU) poses a constant challenge to the management of colorectal cancer (CRC). Consistent efforts were called for to identify molecular markers that can effectively ...predict patients’ response. This study investigated the role of nucleoside transporters, particularly human equilibrative nucleoside transporter 1 (hENT1), in predicting clinical treatment outcome with 5FU-based therapy. Expression of a panel of nucleoside transporters in biopsied tumors from 7 CRC patients was measured by real-time PCR prior to 5FU-based chemotherapy. To provide mechanistic support for the role of hENT1 in 5FU resistance, cell viability of Caco-2 cells was measured, following incubation with varying concentrations of 5FU and a hENT1 inhibitor. Biopsied tumors were further subjected to global metabonomic profiling using gas chromatography/mass spectrometry. High hENT1 levels in tumor tissue correlated with poor clinical response to 5FU. Corroborating with the clinical findings, chemical inhibition of hENT1 in Caco-2 cells resulted in an augmentation of 5FU efficacy. Metabonomic profiling revealed that the pretreatment metabotype associated with non-responders to 5FU therapy was distinct from metabotype of responders (partial least-squares discriminant analysis
Q
2
(cumulative) = 0.898,
R
2
X
= 0.513,
R
2
Y
= 0.996). This is the first clinical report on the relationships of intratumoral expression of nucleoside transporters and tumor metabotype with response to 5FU among CRC patients. Coupled to the in vitro findings, our preliminary data suggested hENT1 to be a potential codeterminant of clinical response to 5FU.
Metabolic profiling provides a powerful diagnostic tool complementary to genomics and proteomics. The pain, discomfort and probable iatrogenic injury associated with invasive or minimally invasive ...diagnostic methods, render them unsuitable in terms of patient compliance and participation. Metabolic profiling of biomatrices like urine, breath, saliva, sweat and feces, which can be collected in a painless manner, could be used for noninvasive diagnosis. This review article covers the noninvasive metabolic profiling studies that have exhibited diagnostic potential for diseases and disorders. Their potential applications are evident in different forms of cancer, metabolic disorders, infectious diseases, neurodegenerative disorders, rheumatic diseases and pulmonary diseases. Large scale clinical validation of such diagnostic methods is necessary in future.
Metabolic profiling involves determination of changes in metabolite levels caused by diseases and can help in their diagnosis. The pain, discomfort and chance of injury associated with painful diagnostic methods, make them unsuitable in terms of patient compliance. Metabolic profiling of body fluids like urine, breath, saliva, sweat and feces, which can be collected in a painless manner, could be used for painless diagnosis. This review article is about such studies, which have exhibited painless diagnostic potential for diseases and disorders. Their applications are evident in cancer, metabolic disorders, infections, neurodegenerative disorders, rheumatic diseases and lung diseases.
Inhibition of acetylcholinesterase (AChE), the key enzyme in the breakdown of acetylcholine, is considered as a promising strategy for the treatment of neurological disorders such as Alzheimer's ...disease, senile dementia, ataxia and myasthenia gravis. A potential source of AChE inhibitors is certainly provided by the abundance of plants in nature. This article aims to provide a comprehensive literature survey of plants that have been tested for AChE inhibitory activity. Numerous phytoconstituents and promising plant species as AChE inhibitors are being reported in this communication.
Background: Developmental toxicology deals with the effects of compounds on fertility and with birth defects that could occur at any stage of the reproductive cycle. In this study, we evaluated the ...teratogenic effects of Lablab purpureus (L.) Sweet beans on zebrafish embryo. Objectives: The developmental toxicity study was carried out to evaluate the toxicity induced by Lablab purpureus (L.) Sweet on zebrafish embryo. We also studied the cytotoxicity of Lablab purpureus (L.) Sweet beans. Methods: Zebrafish embryos were exposed to a methanolic extract of Lablab purpureus (L.) Sweet beans at concentrations of 10,25,50, and 100 μg/ml starting from 24 hours post fertilization (HPF) to 72 HPF. Developmental defects, if any, were observed under a microscope. Cytotoxicity of Lablab purpureus (L.) Sweet beans were also evaluated by using brine shrimp and the corresponding LC50 value of the methanolic extract of Lablab purpureus (L.) Sweet beans were also calculated. Results: The LC50 value of the methanolic extract of Lablab purpureus (L.) Sweet beans were found to be 77 μg/ml. However, some forms of developmental toxicity were observed in zebrafish embryos when treated with different concentrations of Lablab purpureus (L.) Sweet beans extract. Conclusion: The methanolic extract of Lablab purpureus (L.) Sweet beans were found to be cytotoxic in brine shrimp, and the LC50 value was found to be 77 μg/ml. However, there was some level of developmental toxicity in the Zebrafish embryo model at different concentrations of Lablab purpureus (L.) Sweet beans extract.
INTRODUCTION: Dioscorea bulbifera, belonging to the Dioscoreaceae family, found in the Mankundu, West Bengal, India, was traditionally used in anti-microbial activities. It is proven that some of the ...plants of this genus have anti-diabetic properties in its bulb and yam. e.g., Dioscorea alata. So, this study was done to evaluate the anti-diabetic potency of the leaf extract of Dioscorea Bulbiferain diabetic Zebrafish models
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