Degradation product of curcumin restrain Salmonella typhimurium virulent protein L-asparaginase.

OBJECTIVES: Salmonella typhimurium is a pathogen responsible for causing a wide range of infectious diseases. The emergence of multi-drug resistance (MDR) in this microbe is a big challenge. L-asparaginase (less explored drug target) is selected as a drug target because it is actively involved in the virulence mechanism. To block this virulent enzyme, curcumin that is traditionally renowned for its medicinal properties was examined. However, its pharmacological behavior and targeting property is less understood because of its poor bioavailability. Therefore, the present work explores the antimicrobial effect of both curcumin and its degradation product against the MDR pathogen. METHODS: Molecular docking studies were carried out to evaluate the inhibitory effect of curcumin and its degradation product against the L-asparaginase enzyme using Schrodinger Maestro interface tools. The Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) profile of all the test ligands was also performed. RESULTS: The docking score of curcumin was -5.465 kcal/mol while its degradation product curcumin glucuronide has the lowest i.e., -6.240 kcal/mol. All the test ligands showed better or comparable docking scores with respect to control (Ciprofloxacin). Arg 142 and Asn 84 amino acid residues of L-asparaginase were found to be interacting with test ligands inside the binding pocket of the target protein. ADME/toxicology study also indicated the potency of curcumin/curcumin degradation products as a potent inhibitor. CONCLUSIONS: It was found that both curcumin and its degradation products have the potential to inhibit Salmonella. This information could be valuable for futuristic drug candidate development against this pathogen and could be a potential lead for mitigation of MDR.

Pleiotropic Benefits of Statins in Cardiovascular Diseases.

In 1976, Japanese microbiologist Akira Endo discovered the first statin as a product of the fungus Penicillium citrinum that inhibited the activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase. Their primary mode of action is to lower the blood cholesterol by decreasing hepatic cholesterol production, which upregulates hepatic low-density lipoprotein (LDL) receptors and increases LDL-cholesterol clearance. In addition to cholesterol lowering, statins inhibit other downstream products of the mevalonate pathway, causing the so-called pleiotropic effects. As a result of their pleiotropic effects statins modulate virtually all known processes of atherosclerosis and have beneficial effects outside the cardiovascular system Statins inhibit the post-translational prenylation of small GTP-binding proteins such as Rho, Rac, as well as their downstream effectors such as Rho kinase and nicotinamide adenine dinucleotide phosphate oxidases since they suppress the synthesis of isoprenoid intermediates in the cholesterol biosynthetic pathway altering the expression of endothelial nitric oxide synthase, the stability of atherosclerotic plaques, production of proinflammatory cytokines, reactive oxygen species, platelet reactivity, development of cardiac hypertrophy and fibrosis in cell culture and animal experiments. Inhibition of Rho and Rho-associated coiled-coil containing protein kinase (ROCK), has emerged as the principle mechanisms underlying the pleiotropic effects of statins. However, the relative contributions of statin pleiotropy to clinical outcomes are debatable and difficult to measure because the amount of isoprenoid inhibition by statins corresponds to some extent with the amount of LDL-cholesterol decrease. This article examines some of the existing molecular explanations underlying statin pleiotropy and discusses if they have clinical relevance in cardiovascular diseases.

Studies on Regulation of Global Protein Profile and Cellular Bioenergetics of Differentiating SH-SY5Y Cells.

The SH-SY5Y cells differentiated by sequential exposure of retinoic acid (RA) and brain-derived neurotrophic growth factor (BDNF) are a well-employed cellular model for studying the mechanistic aspects of neural development and neurodegeneration. Earlier studies from our lab have identified dramatic upregulation (77 miRNAs) and downregulation (17 miRNAs) of miRNAs in SH-SY5Y cells differentiated with successive exposure of RA + BDNF and demonstrated the essential role of increased levels of P53 proteins in coping with the differentiation-induced changes in protein levels. In continuation to our earlier studies, we have performed unbiased LC-MS/MS global protein profiling of naïve and differentiated SH-SY5Y cells and analyzed the identified proteins in reference to miRNAs identified in our earlier studies to identify the cellular events regulated by both identified miRNAs and proteins. Analysis of LC-MS/MS data has shown a significant increase and decrease in levels of 215 and 163 proteins, respectively, in differentiated SH-SY5Y cells. Integrative analysis of miRNA identified in our previous studies and protein identified in the present study is carried out to discover novel miRNA-protein regulatory modules to elucidate miRNA-protein regulatory relationships of differentiating neurons. In silico network analysis of miRNAs and proteins deregulated upon SH-SY5Y differentiation identified cell cycle, synapse formation, axonogenesis, differentiation, neuron projection, and neurotransmission, as the topmost involved pathways. Further, measuring mitochondrial dynamics and cellular bioenergetics using qPCR and Seahorse XFp Flux Analyzer, respectively, showed that differentiated cells possess increased mitochondrial dynamics and OCR relative to undifferentiated cells. In summary, our studies have identified a novel set of proteins deregulated during neuronal differentiation and establish the role of miRNAs identified in earlier studies in the regulation of proteins identified by LC-MS/MS-based global profiling of differentiating neurons, which will help in future studies related to neural development and neurodegeneration.

Detection of circulating tumour cells in colorectal cancer: Emerging techniques and clinical implications.

Despite several advances in oncological management of colorectal cancer, morbidity and mortality are still high and devastating. The diagnostic evaluation by endoscopy is cumbersome, which is uncomfortable to many. Because of the intra- and inter-tumour heterogeneity and changing tumour dynamics, which is continuous in nature, the diagnostic biopsy and assessment of the pathological sample are difficult and also not adequate. Late manifestation of the disease and delayed diagnosis may lead to relapse or metastases. One of the keys to improving the outcome is early detection of cancer, ease of technology to detect with uniformity, and its therapeutic implications, which are yet to come. "Liquid biopsy" is currently the most recent area of interest in oncology, which may provide important tools regarding the characterization of the primary tumour and its metastasis as cancer cells shed into the bloodstream even at the early stages of the disease. By using this approach, clinicians may be able to find out information about the tumour at a given time. Any of the following three types of sampling of biological material can be used in the "liquid biopsy". These are circulating tumour cells (CTCs), circulating tumour DNA, and exosomes. The most commonly studied amongst the three is CTCs. CTCs with their different applications and prognostic value has been found useful in colorectal cancer detection and therapeutics. In this review, we will discuss various markers for CTCs, the core tools/techniques for detection, and also important findings of clinical studies in colorectal cancer and its clinical implications.

Drug-likeness prediction of designed analogues of isoniazid standard targeting FabI enzyme regulation from P. falciparum.

Fatty acid biosynthesis enzymes (Fab enzyme) are important targets for anti-malarial drug development. The present study describes the toxicity screening of designed novel analogues which inhibit FabI enzyme regulation, a protein with multifunctional property. New analogues were prepared using ChemDraw Ultra 10 Software and converted into 3D PDB structure format for binding studies with FabI (PDB ID: 4IGE). Further Lipinski's rule of FIVE and ADMET profiling for toxicity prediction has been performed on the designed analogues. The result shows that ISN-23 is potential analogue exhibiting inhibition at the active site of FabI enzyme with good binding features.

Influence of IL-1ß, STAT3 & 5 and TLR-5 gene polymorphisms on rheumatic heart disease susceptibility in north Indian population.

BACKGROUND: Rheumatic heart disease (RHD) is the most serious complication of heart that comprises inflammatory reactions in heart valves. Many studies have demonstrated the contribution of host genetic factors in susceptibility to RHD and many cytokine gene variants have been linked with susceptibility to RHD. We sought to determine the role of genetic variants in IL-1ß, STAT3, STAT5B and TLR5 genes in conferring risk of RHD in two cohorts of RHD patients. METHODS: The study included 400 echocardiography confirmed RHD patients and 300 controls from North Indian Population. We categorized RHD patients into two sub-groups based on involvement of heart valves, mitral valve lesion alone (MVL), and combined valve lesions including mitral valve (CVL). Genotyping for all the polymorphisms was done using TaqMan /PCR-RFLP methods. RESULTS: Our results showed that the genotypic frequencies of IL-1ß, STAT3, STAT5B andTLR5 genes polymorphisms were significantly associated with RHD risk. To validate our results, we performed a replication study in additional 200 cases with similar clinical characteristics and results again confirmed consistent findings with RHD risk. In subgroup analysis, STAT3 polymorphism remained significant with MVL in RHD patients. CONCLUSION: IL-1ß, STAT3, STAT5B and TLR5 genes polymorphism may be useful markers for the identification of individuals with high risk of RHD in the susceptible population.

Hesperidin Induces ROS-Mediated Apoptosis along with Cell Cycle Arrest at G2/M Phase in Human Gall Bladder Carcinoma.

A natural predominant flavonoid hesperidin rich in citrus fruits exhibits multifunctional medicinal properties. The anticancerous potential of hesperidin has been widely explored; however, the gall bladder carcinoma (GBC) still remains untouched due to the unavailability of efficient experimental model. The aim of our study was to identify the apoptotic and antiproliferative potential of hesperidin in GBC. The promising efficacy of hesperidin was assessed through the generation of reactive oxygen species (ROS), cellular apoptosis, and loss of mitochondrial membrane potential (MMP) in the primary cells generated from surgically removed cancerous gall bladder tissues. Moreover, cell cycle analysis and caspases-3 activity were performed to confirm the apoptosis inducing potential of hesperidin. Results revealed that hesperidin exposure for 24 h at a dose of 200 µM reduced the cell proliferation of GBC cells significantly. In addition, hesperidin treatment further resulted in an increased ROS generation and nuclear condensation at the same dose. Caspase-3 activation and cell cycle arrest at G2/M phase were also accelerated in a dose-dependent manner. Together, these results suggest that hesperidin can be considered as a potential anticancerous compound for the treatment of GBC. Furthermore, evaluation of the pharmacological aspects of hesperidin is desirable for drug development.

Correlation of CD133 and Oct-4 expression with clinicopathological and demographic parameters in oral squamous cell carcinoma patients.

OBJECTIVE: Squamous cell carcinoma of oral cavity is one of the most common cancers of Indian subcontinent with the 5-year survival rate of 50% despite the recent advances in the treatment. The aim of the present study was to study cancer stem cell markers CD133 and Oct-4 in oral squamous cell carcinoma (OSCC) patients and their correlation with clinicopathological variables. MATERIALS AND METHODS: This was a prospective study which included 50 cases of histopathologically proven squamous cell carcinoma of oral cavity. Expression of CD133 and Oct-4 was evaluated by immunohistochemistry (IHC) and their expression was correlated with various clinicopathological and demographic parameters. RESULTS: CD133 expression was seen in 20.6% cases of clinical Stage I-II and in 79.4% of clinical stage of III-IV OSCC patients, the difference being statistically significant with the P = 0.048. There was no statistically significant association between CD133 expression and any other clinicopathological or demographic variable. Oct-4 was expressed only in one case. CONCLUSIONS: CD133 expression was significantly seen higher in Stage III-IV tumors, the stem cells may be responsible for the aggressiveness of the OSCCs and these stem cells can be potential prognostic markers and targets for the future targeted therapy.

Influence of cytokine gene polymorphism on the risk of rheumatic heart disease - A meta-analysis.

RHD is an inflammatory disease resulting from interactive immune, genetic, and environmental factors. Various, epidemiological studies have shown the association of genetic variants of cytokine genes with a predisposition to RHD. However, the results from different populations are inconsistent. Therefore, we carried out a meta- analysis of twenty-three published case-control studies and the results indicated that TGF-ß1 +869 T/C (T vs. C: OR = 7.68, 95% CI = 1.62-36.50; TT + CT vs. CC OR = 1.83, 95%CI = 1.39-2.41), TGF-ß1-509 (T vs. C: OR = 2.76, 95% CI = 1.33-5.75), TNF-α(AA vs. GG: OR = 4.93,95% CI = 2.83-8.58; A vs. G: OR = 2.15, 95% CI = 1.13-4.12) and IL-1ß -511C/T (CC + CT vs. TT: OR = 1.35, 95%CI = 1.02-1.78; C vs. T: OR = 2.36, 95% CI = 1.66-3.37) were significantly associated with increased risk of RHD. On the other hand, IL-10(-1082)G/A polymorphism (GA vs. AA: OR = 0.91, 95% CI = 0.36-2.33; G vs. A: OR = 1.90, 95% CI = 0.58-6.22) and IL-6-174 G/C (CC + GC vs. GG: OR = 0.68, 95%CI = 0.32-1, C vs. G: OR = 1.14, 95% CI = 0.82-1.60) were not associated with modified RHD risk. The meta-analysis results were similar in Asians and non-Asians. Therefore, cytokine gene polymorphisms play important role in the genetic susceptibility of RHD in rheumatic fever patients.

Nanoparticles as a Carrier System for Drug Delivery Across Blood Brain Barrier.

Brain, the centre of the nervous system and an integral part the body, is protected by two anatomical and physiological barriers- Blood-Brain Barrier (BBB) and Blood-Cerebrospinal Fluid Barrier (BCSFB). Blood-Brain Barrier is a very complex and highly organized multicellular structure that shields the brain from harmful substances and invading organisms from the bloodstream and thus offering protection against various brain diseases and injuries. However, it also impede the effective delivery of drug to the brain, thus, preventing treatment of numerous neurological disorders. Even though various traditional approaches such as Intra-Cerebro-Ventricular (ICV) injection, use of implants, disruption of BBB and use of prodrugs have achieved some success in overcoming these barriers, researchers are continuously working for promising alternatives for improved brain drug delivery. Recent breakthroughs in the field of nanotechnology provide an appropriate solution to problems associated with these delivery approaches and thus can be effectively used to treat a wide variety of brain diseases. Thus, nanotechnology promises to bring a great future to the individuals with various brain disorders. This review provides a brief overview of various brain drug delivery approaches along with limitations. In addition, the significance of nanoparticles as drug carrier systems for effective brain specific drug delivery has been highlighted. To show the complexity of the problems to be overcome for improved brain drug delivery, a concise intercellular classification of the BBB along with general transport routes across it is also included.

Computer Aided Drug Design: Success and Limitations.

Over the last few decades, computer-aided drug design has emerged as a powerful technique playing a crucial role in the development of new drug molecules. Structure-based drug design and ligand-based drug design are two methods commonly used in computer-aided drug design. In this article, we discuss the theory behind both methods, as well as their successful applications and limitations. To accomplish this, we reviewed structure based and ligand based virtual screening processes. Molecular dynamics simulation, which has become one of the most influential tool for prediction of the conformation of small molecules and changes in their conformation within the biological target, has also been taken into account. Finally, we discuss the principles and concepts of molecular docking, pharmacophores and other methods used in computer-aided drug design.