Global DNA methylation profiling of manganese-exposed human neuroblastoma SH-SY5Y cells reveals epigenetic alterations in Parkinson’s disease-associated genes

Manganese (Mn) is an essential trace element required for optimal functioning of cellular biochemical pathways in the central nervous system. Elevated exposure to Mn through environmental and occupational exposure can cause neurotoxic effects resulting in manganism, a condition with clinical symptoms identical to idiopathic Parkinson’s disease. Epigenetics is now recognized as a biological mechanism involved in the etiology of various diseases. Here, we investigated the role of DNA methylation alterations induced by chronic Mn (100 µM) exposure in human neuroblastoma (SH-SY5Y) cells in relevance to Parkinson’s disease. A combined analysis of DNA methylation and gene expression data for Parkinson’s disease-associated genes was carried out. Whole-genome bisulfite conversion and sequencing indicate epigenetic perturbation of key genes involved in biological processes associated with neuronal cell health. Integration of DNA methylation data with gene expression reveals epigenetic alterations to PINK1, PARK2 and TH genes that play critical roles in the onset of Parkinsonism. The present study suggests that Mn-induced alteration of DNA methylation of PINK1–PARK2 may influence mitochondrial function and promote Parkinsonism. Our findings provide a basis to further explore and validate the epigenetic basis of Mn-induced neurotoxicity

Manganese exposure: linking down-regulation of miRNA-7 and miRNA-433 with α-synuclein overexpression and risk of idiopathic Parkinson's disease

Manganese is an essential trace element however elevated environmental and occupational exposure to this element has been correlated with neurotoxicity symptoms clinically identical to idiopathic Parkinson's disease. In the present study we chronically exposed human neuroblastoma SH-SY5Y cells to manganese (100 μM) and carried out expression profiling of miRNAs known to modulate neuronal differentiation and neurodegeneration. The miRNA PCR array results reveal alterations in expression levels of miRNAs, which have previously been associated with the regulation of synaptic transmission and apoptosis. The expressions of miR-7 and miR-433 significantly reduced upon manganese exposure. By in silico homology analysis we identified SNCA and FGF-20as targets of miR-7 and miR-433. We demonstrate an inverse correlation in expression levels where reduction in these two miRNAs causes increases in SNCA and FGF-20. Transient transfection of SH-SY5Y cells with miR-7 and miR-433 mimics resulted in down regulation of SNCA and FGF-20 mRNA levels. Our study is the first to uncover the potential link between manganese exposure, altered miRNA expression and parkinsonism: manganese exposure causes overexpression of SNCA and FGF-20 by diminishing miR-7 and miR-433 levels. These miRNAs may be considered critical for protection from manganese induced neurotoxic mechanism and hence as potential therapeutic targets

암 세포 내 Caspase 단계적 연쇄반응의 동시다발적 정량적 다변량 이미징 세포계수에 기초한 약물 유발 세포죽음 동력학에 대한 연구

Thesis(doctors) --서울대학교 대학원 :약학과(약품분석학전공),2009.8.Docto

Adsorption of an emerging contaminant (primidone) onto activated carbon: kinetic, equilibrium, thermodynamic, and optimization studies

The current study addresses the removal of an emerging environmental contaminant (primidone) in batch adsorption experiments using commercial-grade powdered activated charcoal (PAC). The experiments for the removal of primidone were performed to identify the effect of various adsorption parameters. The secondorder rate expression best represented the adsorption kinetics data. The Freundlich isotherm equation was best fitted to the experimental adsorption data at equilibriumfor removal of primidone using PAC. The values for change in entropy (ΔSo) were positive, which indicates that the degree of freedomof the process increases. The negative values of change in enthalpy (ΔHo) and change in Gibb’s free energy (ΔGo) indicate that the physical adsorption is a dominant phenomenon, and the process is feasible and spontaneous. The negative value of ΔHo also represented the exothermicity of the adsorption process. The Taguchi optimization technique calculated the influence of variation of different process parameters, viz., initial pH (pH0), PAC dosage (m), initial adsorbate concentration (C0), solution temperature (T), and process contact time (t), on the removal of primidone by adsorption from aqueous solution. Each of the above parameters was examined at three levels to study their effects on the adsorptive uptake of primidone using PAC (qe, mg g−1), and the optimum value necessary to maximize qe was determined. The findings from the ANOVA indicate that the PAC dose (m) is the most notable parameter contributing 62.16% to qe and a 71.96% to the signal to noise (S/N) ratio data, respectively. The confirmation experiments performed at the optimum parameter condition validated the applicability of the Taguchi design of experiments. The percent removal and adsorptive uptake at the optimal condition were 86.11% and 0.258 mg g−1, respectively

Personal and social issues involved in cancer development

Cancer is termed as a group of diseases and caused due to several genetic and environmental factors. Personal and social environments mostly decide the fate of cancer development in the community. With the advancement in cancer research, new therapeutic drugs and instruments have been developed to treat and cure cancer at an early stage of its development. However, less priority was given on the personal and social issues. Thus, the present review discusses the role of personal and social issues involved in the development of cancer

Carbonic anhydrase mediated carbon dioxide sequestration: Promises, challenges and future prospects

Anthropogenic activities have substantially increased the level of greenhouse gases (GHGs) in the atmosphere and are contributing significantly to the global warming. Carbon dioxide (CO2) is one of the major GHGs which plays a key role in the climate change. Various approaches and methodologies are under investigation to address CO2 capture and sequestration worldwide. Carbonic anhydrase (CA) mediated CO2 sequestration is one of the promising options. Therefore, the present review elaborates recent developments in CA, its immobilization and bioreactor methodologies towards CO2 sequestration using the CA enzyme. The promises and challenges associated with the efficient utilization of CA for CO2 sequestration and scale up from flask to lab‐scale bioreactor are critically discussed. Finally, the current review also recommends the possible future needs and directions to utilize CA for CO2 sequestration

Cellular alterations and modulation of protein expression in bitumen-challenged human osteoblast cells

Purpose There are many arguments on the carcinogenic potential of bitumen extract. The mechanism of bitumen-induced damage is not well understood at the molecular level. Therefore, in the present study, cell-transforming and tumor-inducing potential of bitumen extract was studied using in vitro [human osteosarcoma (HOS) cells] and in vivo [nude and severe combined immunodeficiency (SCID) mice] models. Methods Gas chromatography/mass spectrometry (GC/MS) analysis was carried out to find out the existence of carcinogenic compounds in the bitumen extract. Cell transformation test, anchorage independence assay, karyotyping assay, tumorigenicity assay, and 2-DE analysis were used to find out the effect of bitumen using the in vitro and in vivo models. Results GC/MS analysis showed the existence of carcinogenic compounds in the bitumen extract. HOS cells were treated with different concentrations (25, 50, and 100 μl/ml) of bitumen extract. Compared to the parental HOS cells, bitumen transformants (HOS T1 and HOS T2) showed the characteristics of anchorage independency, chromosomal anomaly, and cellular transformation. Interestingly, bitumen transformants were not able to form tumor in nude/SCID mice. Proteomic analysis revealed the existence of 19 differentially expressed proteins involved in progression of cancer, angiogenesis, cell adhesion, etc. Conclusions Exposure of bitumen extract to HOS cells results in the cellular transformation similar to cancer cells and can modulate proteins involved in the progression of cancer. We state that the non-tumorogenic potential of bitumen transformant in nude/SCID mice can be attributed to the downregulation of galectin-1, chromodomain helicase DNA-binding protein 1-like gene, and membrane-associated guanylate kinase 2 protein

Simultaneous quantitative monitoring of four indicator contaminants of emerging concern (CEC) in different water sources of Central India using SPE/LC-(ESI)MS-MS

Environmental occurrence of CECs poses a great threat to both aquatic life and human health. The aim of this study was to optimize and validate SPE/ LC-(ESI)MS-MS method for simultaneous quantitative monitoring of two sub-classes of CECs (pharmaceuticals and hormones) and to estimate the concentrations of select CECs in environmental water samples. For all the tested analytes, recoveries in laboratory reagent water were greater than 81%. Average percent (relative standard deviation) RSD of the analytes in recovery, repeatability, and reproducibility experiments were ≤ 10%. Determination coefficients (r2) of primidone, diclofenac, testosterone, and progesterone were estimated to be 0.9979, 0.9972, 0.9968, and 0.9962, respectively. Limits of detection (LOD) for primidone, diclofenac, testosterone, and progesterone were 4.63 ng/L, 5.36 ng/L, 0.55 ng/L, and 0.88 ng/L, respectively. Limits of quantification (LOQ) for primidone, diclofenac, testosterone, and progesterone were 14.72 ng/L, 17.06 ng/L, 1.766 ng/L, and 2.813 ng/L, respectively. Average recoveries in environmental water and wastewater samples were greater than 74% and RSD were ≤ 7%. Trace levels (68.33–125.70 ng/L) of primidone were detected in four environmental water samples, whereas diclofenac was not detected in any of the tested sample. Trace levels of progesterone were observed in two environmental samples (16.64 – 203.73 ng/L), whereas testosterone was detected in STP inlet sample (178.16 ng/L)

Genetic polymorphism of CYP2D6*2 C? T 2850, GSTM1, NQO1 genes and their correlation with biomarkers in manganese miners of Central India

Manganese (Mn) intoxication is most often regarded as an occupational manifestation and occurs in places such as manganese mines, dry cell battery plants and ceramic industries. In the present study, the influence of genetic polymorphism in cytochrome P450 2D6 (CYP2D6*2), glutathione S-transferase M1 (GSTM1) and NAD(P)H quinone oxidoreductase 1 (NQO1) genes on blood manganese and plasma prolactin concentrations in manganese miners was investigated. Genotyping of CYP2D6*2 C ? T 2850 and NQO1 C ? T 609 was carried out using polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) whereas the genotyping of GSTM1 was carried out by multiplex PCR using beta globin as an internal control. Manganese miners with CYP2D6*2 C ? T 2850 variant genotype had relatively low Mn concentration [GM: 21.4 ± 8.9 lg L1 ] than the subjects with wild (GM: 36.3 ± 8.5 lg L1 ) and heterozygous (GM: 34.4 ± 6.9 lg L1 ) genotypes. Miners with CYP2D6*2 variant genotypes showed low prolactin levels (GM: 13.13 ± 1.6 ng mL1 ) compared to the wild (GM: 16.4.4 ± 1.5 lg L1 ) and heterozygous (GM: 18.7 ± 1.6 ng mL1 ) genotypes. Gene–gene interaction studies also revealed that the subjects with CYP2D6*2 C ? T 2850 variant genotypes had low levels of Mn and prolactin. Our new findings suggest that CYP2D6*2 C ? T 2850 variant genotypes can regulate plasma prolactin levels in manganese miners of Central India and could be involved in the fast metabolism of blood manganese, compared to wild and heterozygous genotypes. 20

Noncoding RNAs: Possible Players in the Development of Fluorosis

Fluorosis is caused by excess of fluoride intake over a long period of time. Aberrant change in the Runt-related transcription factor 2 (RUNX2) mediated signaling cascade is one of the decisive steps during the pathogenesis of fluorosis. Up to date, role of fluoride on the epigenetic alterations is not studied. In the present study, global expression profiling of short noncoding RNAs, in particular miRNAs and snoRNAs, was carried out in sodium fluoride (NaF) treated human osteosarcoma (HOS) cells to understand their possible role in the development of fluorosis. qPCR and in silico hybridization revealed that miR-124 and miR-155 can be directly involved in the transcriptional regulation of Runt-related transcription factor 2 (RUNX2) and receptor activator of nuclear factor \uce\uba-B ligand (RANKL) genes. Compared to control, C/D box analysis revealed marked elevation in the number of UG dinucleotides and D-box sequences in NaF exposed HOS cells. Herein, we report miR-124 and miR-155 as the new possible players involved in the development of fluorosis. We show that the alterations in UG dinucleotides and D-box sequences of snoRNAs could be due to NaF exposure