Manish Sharma

Cardioprotective Role of Syzygium cumini Against Glucose-Induced Oxidative Stress in H9C2 Cardiac Myocytes

Diabetic patients are known to have an independent risk of cardiomyopathy. Hyperglycemia leads to upregulation of reactive oxygen species (ROS) that may contribute to diabetic cardiomyopathy. Thus, agents that suppress glucose-induced intracellular ROS levels can have therapeutic potential against diabetic cardiomyopathy. Syzygium cumini is well known for its anti-diabetic potential, but its cardioprotective properties have not been evaluated yet. The aim of the present study is to analyze cardioprotective properties of methanolic seed extract (MSE) of S. cumini in diabetic in vitro conditions. ROS scavenging activity of MSE was studied in glucose-stressed H9C2 cardiac myoblasts after optimizing the safe dose of glucose and MSE by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide. 2′,7′-dichlorfluorescein diacetate staining and Fluorescence-activated cell sorting analysis confirmed the suppression of ROS production by MSE in glucose-induced cells. The intracellular NO and H2O2 radical–scavenging activity of MSE was found to be significantly high in glucose-induced cells. Exposure of glucose-stressed H9C2 cells to MSE showed decline in the activity of catalase and superoxide dismutase enzymes and collagen content. 4′,6-diamidino-2-phenylindole, propidium iodide and 10-N-nonyl-3,6-bis (dimethylamino) acridine staining revealed that MSE protects myocardial cells from glucose-induced stress. Taken together, our findings revealed that the well-known anti-diabetic S. cumini can also protect the cardiac cells from glucose-induced stress.

Cerium oxide nanoparticles prevent apoptosis in primary cortical culture by stabilizing mitochondrial membrane potential

Abstract Cerium oxide nanoparticles (CNPs) of spherical shape have unique antioxidant capacity primarily due to alternating + 3 and + 4 oxidation states and crystal defects. Several studies revealed the protective efficacies of CNPs in cells and tissues against the oxidative damage. However, its effect on mitochondrial functioning, downstream effectors of radical burst and apoptosis remains unknown. In this study, we investigated whether CNPs treatment could protect the primary cortical cells from loss of mitochondrial membrane potential (Δψm) and Δψm-dependent cell death. CNPs with spherical morphology and size range 7–10 nm were synthesized and utilized at a concentration of 25 nM on primary neuronal culture challenged with 50 μM of hydrogen peroxide (H2O2). We showed that optimal dose of CNPs minimized ROS content of the cells and also curbed related surge in cellular calcium flux. Importantly, CNPs treatment prevented apoptotic loss of cell viability. Reduction in the apoptosis could be successfully attributed to the maintenance of Δψm and restoration of major redox equivalents NADH/NAD+ ratio and cellular ATP. These findings, therefore, suggest possible route of CNPs protective efficacies in primary cortical culture.

Curcumin Suppresses Gelatinase B Mediated Norepinephrine Induced Stress in H9c2 Cardiomyocytes

Background Extracellular matrix (ECM) remodeling facilitates biomechanical signals in response to abnormal physiological conditions. This process is witnessed as one of the major effects of the stress imposed by catecholamines, such as epinephrine and norepinephrine (NE), on cardiac muscle cells. Matrix metalloproteinases (MMPs) are the key proteases involved in degradation of the ECM in heart. Objectives The present study focuses on studying the effect of curcumin on Gelatinase B (MMP-9), an ECM remodeling regulatory enzyme, in NE-induced cardiac stress. Curcumin, a bioactive polyphenol found in the spice turmeric, has been studied for its multi-fold beneficial properties. This study focuses on investigating the role of curcumin as a cardio-protectant. Methods H9c2 cardiomyocytes were subjected to NE and curcumin treatments to study the response in stress conditions. Effect on total collagen content was studied using Picrosirus red staining. Gelatinase B activity was assessed through Gel-Diffusion Assay and Zymographic techniques. RT-PCR, Western Blotting and Immunocytochemistry were performed to study effect on expression of gelatinase B. Further, the effect of curcumin on the localization of NF-κB, known to regulate gelatinase B, was also examined. Results Curcumin suppressed the increase in the total collagen content under hypertrophic stress and was found to inhibit the in-gel and in-situ gelatinolytic activity of gelatinase B. Moreover, it was found to suppress the mRNA and protein expression of gelatinase B. Conclusions The study provides an evidence for an overall inhibitory effect of curcumin on Gelatinase B in NE-induced hypertrophic stress in H9c2 cardiomyocytes which may contribute in the prevention of ECM remodeling.

An assessment of norepinephrine mediated hypertrophy to apoptosis transition in cardiac cells: A signal for cell death

OBJECTIVES Heart is an organ which is under a constant work load that generates numerous stress responses. Heart failure is associated with increased plasma norepinephrine (NE) and hypertrophic cell death. Within the current study we try to understand the concentration dependent molecular switch from hypertrophy to apoptosis under stress. METHODS The effect of increasing concentration of NE on cell death was studied using MTT assay based on which further experimental conditions were decided. Trypan Blue staining and TUNEL assay were done at selected concentrations of NE. Cellular and nuclear morphology at these concentrations was studied using Haematoxylin-Eosin, DAPI and PI stains. The molecular switch between hypertrophy and cell death was studied by expression analysis of β-MyHC and TNF-α. Rhodamine and DCFH-DA staining were done to evaluate the role of mitochondria and ROS under these conditions. Role of caspases under these transitions was also evaluated. RESULT NE shows steep falls in cell viability at 50 μM and 100 μM concentrations. The cellular and nuclear morphology is altered at these concentrations along with alterations at molecular level showing a shift from hypertrophy towards cell death. Altered mitochondrial membrane potential and increase in ROS support this which leads to caspase dependent activation of cell death. CONCLUSION We show that at 50 μM NE, there occurs a transition from cellular hypertrophy towards death. This could be beneficial to prevent hypertrophy induced cardiac cell death and evaluating cardio protective therapeutic targets in vitro.

An efficient approach for privacy preserving in data mining

In many organizations large amount of data are collected. These data are sometimes used by the organizations for data mining tasks. However, the data collected may contain private or sensitive information which should be protected. Privacy protection is an important issue if we release data for the mining or sharing purpose. Privacy preserving data mining techniques allow publishing data for the mining purpose while at the same time preserve the private information of the individuals. Many techniques have been proposed for privacy preservation but they suffer from various types of attacks and information loss. In this paper we proposed an efficient approach for privacy preservation in data mining. Our technique protects the sensitive data with less information loss which increase data usability and also prevent the sensitive data for various types of attack. Data can also be reconstructed using our proposed technique.

H2S Regulates Hypobaric Hypoxia-Induced Early Glio-Vascular Dysfunction and Neuro-Pathophysiological Effects

Hypobaric Hypoxia (HH) is an established risk factor for various neuro-physiological perturbations including cognitive impairment. The origin and mechanistic basis of such responses however remain elusive. We here combined systems level analysis with classical neuro-physiological approaches, in a rat model system, to understand pathological responses of brain to HH. Unbiased ‘statistical co-expression networks’ generated utilizing temporal, differential transcriptome signatures of hippocampus—centrally involved in regulating cognition—implicated perturbation of Glio-Vascular homeostasis during early responses to HH, with concurrent modulation of vasomodulatory, hemostatic and proteolytic processes. Further, multiple lines of experimental evidence from ultra-structural, immuno-histological, substrate-zymography and barrier function studies unambiguously supported this proposition. Interestingly, we show a significant lowering of H2S levels in the brain, under chronic HH conditions. This phenomenon functionally impacted hypoxia-induced modulation of cerebral blood flow (hypoxic autoregulation) besides perturbing the strength of functional hyperemia responses. The augmentation of H2S levels, during HH conditions, remarkably preserved Glio-Vascular homeostasis and key neuro-physiological functions (cerebral blood flow, functional hyperemia and spatial memory) besides curtailing HH-induced neuronal apoptosis in hippocampus. Our data thus revealed causal role of H2S during HH-induced early Glio-Vascular dysfunction and consequent cognitive impairment.

Genome Wide Expression Analysis Suggests Perturbation of Vascular Homeostasis during High Altitude Pulmonary Edema

Background High altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic edema which occurs in unacclimatized but otherwise normal individuals within two to four days after rapid ascent to altitude beyond 3000 m. The precise pathoetiology and inciting mechanisms regulating HAPE remain unclear. Methodology/Principle findings We performed global gene expression profiling in individuals with established HAPE compared to acclimatized individuals. Our data suggests concurrent modulation of multiple pathways which regulate vascular homeostasis and consequently lung fluid dynamics. These pathways included those which regulate vasoconstriction through smooth muscle contraction, cellular actin cytoskeleton rearrangements and endothelial permeability/dysfunction. Some notable genes within these pathways included MYLK; rho family members ARGEF11, ARHGAP24; cell adhesion molecules such as CLDN6, CLDN23, PXN and VCAM1 besides other signaling intermediates. Further, several important regulators of systemic/pulmonary hypertension including ADRA1D, ECE1, and EDNRA were upregulated in HAPE. We also observed significant upregulation of genes involved in paracrine signaling through chemokines and lymphocyte activation pathways during HAPE represented by transcripts of TNF, JAK2, MAP2K2, MAP2K7, MAPK10, PLCB1, ARAF, SOS1, PAK3 and RELA amongst others. Perturbation of such pathways can potentially skew vascular homeostatic equilibrium towards altered vascular permeability. Additionally, differential regulation of hypoxia-sensing, hypoxia-response and OXPHOS pathway genes in individuals with HAPE were also observed. Conclusions/Significance Our data reveals specific components of the complex molecular circuitry underlying HAPE. We show concurrent perturbation of multiple pathways regulating vascular homeostasis and suggest multi-genic nature of regulation of HAPE.

Norepinephrine-induced apoptotic and hypertrophic responses in H9c2 cardiac myoblasts are characterized by different repertoire of reactive oxygen species generation

Despite recent advances, the role of ROS in mediating hypertrophic and apoptotic responses in cardiac myocytes elicited by norepinephrine (NE) is rather poorly understood. We demonstrate through our experiments that H9c2 cardiac myoblasts treated with 2 µM NE (hypertrophic dose) generate DCFH-DA positive ROS only for 2 h; while those treated with 100 µM NE (apoptotic dose) sustains generation for 48 h, followed by apoptosis. Though the levels of DCFH fluorescence were comparable at early time points in the two treatment sets, its quenching by DPI, catalase and MnTmPyP suggested the existence of a different repertoire of ROS. Both doses of NE also induced moderate levels of H2O2 but with different kinetics. Sustained but intermittent generation of highly reactive species detectable by HPF was seen in both treatment sets but no peroxynitrite was generated in either conditions. Sustained generation of hydroxyl radicals with no appreciable differences were noticed in both treatment sets. Nevertheless, despite similar profile of ROS generation between the two conditions, extensive DNA damage as evident from the increase in 8-OH-dG content, formation of γ-H2AX and PARP cleavage was seen only in cells treated with the higher dose of NE. We therefore conclude that hypertrophic and apoptotic doses of NE generate distinct but comparable repertoire of ROS/RNS leading to two very distinct downstream responses.

NAP (davunetide) protects primary hippocampus culture by modulating expression profile of antioxidant genes during limiting oxygen conditions

Abstract Hypoxia is a well-known threat to neuronal cells and triggers the pathophysiological syndromes in extreme environments such as high altitudes and traumatic conditions such as stroke. Among several prophylactic molecules proven suitable for ameliorating free radical damage, NAP (an octapeptide with initial amino acids: asparagine/N, alanine/A, and proline/P) can be considered superlative, primarily due to its high permeability into brain through blood–brain barrier and observed activity at femtomolar concentrations. Several mechanisms of action of NAP have been hypothesized for its protective role during hypoxia, yet any distinct mechanism is unknown. Oxidative stress is advocated as the leading event in hypoxia; we, therefore, investigated the regulation of key antioxidant genes to understand the regulatory role of NAP in providing neuroprotection. Primary neuronal culture of rat was subjected to cellular hypoxia by limiting the oxygen concentration to 0.5% for 72 h and observing the prophylactic efficacies of 15fM NAP by conventional cell death assays using flow cytometry. We performed real-time quantitative polymerase chain reaction to comprehend the regulatory mechanism. Further, we validated the significantly regulated candidates by enzyme assays and immunoblotting. In the present study, we report that NAP regulates a major clad of cellular antioxidants and there is an involvement of more than one route of action in neuroprotection during hypoxia.

Query Processing Performance and Searching over Encrypted Data by using an Efficient Algorithm

Data is the central asset of todays dynamically operating organization and their business. This data is usually stored in database. A major consideration is applied on the security of that data from the unauthorized access and intruders. Data encryption is a strong option for security of data in database and especially in those organizations where security risks are high. But there is a potential disadvantage of performance degradation. When we apply encryption on database then we should compromise between the security and efficient query processing. The work of this paper tries to fill this gap. It allows the users to query over the encrypted column directly without decrypting all the records. Its improves the performance of the system. The proposed algorithm works well in the case of range and fuzzy match queries.