Showing papers in "Modares Journal of Medical Sciences: Pathobiology in 2015"

Evaluation of Cr (VI) induced Neurotoxicity and Oxidative Stress in PC12 Cells

Abstract: Objective: Hexavalent chromium [Cr (VI)] compounds are well-known environmental contaminants generated from industrial processes. Several studies have reported the harmful effects of Cr (VI) on different organs, however, little is known about neurotoxic effects of Cr (VI). The aim of this study is to investigate the toxic effects of Cr (VI) on PC12 cells. Methods : PC12 cells were cultured following standard protocol and exposed to various concentrations (1-100 μM) of potassium dichromate (K2Cr2O7) for 24, 48 and 72 h. After exposure, cell viability was measured by the MTT assy. Also following exposure, production of reactive oxygen species (ROS) and lipid peroxidation were measured. Results: Potassium dichromate induced significant cell death in PC12 cells. The IC50 values for cytotoxicity were 22.02 for 24 h, 1.88 for 48 h, and 1.85 for 72 h of exposure. Significant differences between IC50 for 24 h of exposure compared to 48 and 72 h of exposure were observed (p<0.05). ROS production and lipid peroxidation significantly increased in the Cr (VI) treated groups compared to the control group (p<0.05). Conclusion: The results indicated that Cr (VI) induced dose and time dependent cytotoxicity in PC12 cells which indicated neurotoxic effects of Cr (VI). Mechanisms of Cr (VI) induced toxicity have not been fully determined, however increased production of ROS and lipid peroxidation in Cr (VI) treated groups demonstrated that oxidative stress might be involved in neurotoxicity of Cr (VI).

Evaluation of Poly(amidoamine) Dendrimer Surface Modification with Poly(ethylene glycol) on Cytotoxicity Reduction

Abstract: Objective: Generation 5 poly (amidoamine) dendrimers are promising multipotent gene delivery vectors that provide favorable DNA condensation properties; however, their high toxicity limits their applications. Toxicity of PAMAM dendrimers depends on their type, generation and applied dosage in a way that lower generations (lower than G5 dendrimers) and anionic dendrimers have lower toxicity than higher generations and cationic dendrimers. The aim of this study is to evaluate the effect of PEGylation on toxicity of G5 PAMAM dendrimers. Methods: In this study, to improve their characteristics as gene delivery carriers, G5 PAMAM dendrimers were conjugated to polyethylene glycol molecules (PEG, molecular weight 3500) at three different molar ratios of 10, 20 and 30. Also the number of conjugated PEG chains was quantified using TNBSA and Ellman assays. The effect of different degrees of PEGylation on cytotoxicity and transfection efficiency of modified PAMAM dendrimers toward BT-474 and MCF-10A cell lines were assessed. Results: Compared to unconjugated, PEG conjugated PAMAM dendrimers had lower in vitro cytotoxicity, particularly at higher PEG to PAMAM molar ratios. Among all prepared PEG-PAMAM dendrimers, G5 PAMAM dendrimers that conjugated to PEG at a molar ratio of 10/1 had the highest in vitro transfection rate in both cell lines. Conclusion: Our results showed that these PEG-conjugated PAMAM dendrimers possess a great potential for in vitro gene delivery.

Changes in Matrix Metallo-proteinases 2, 9 and Tissue Inhibitor of Matrix Metalloproteinase 1 to Synchronized Exercise Training and Celery, as an Herbal Supplement, in Overweight Women

Abstract: Objective: Obesity increases production of the extracellular matrix (ECM) role in pathological cardiovascular damage. Regular exercise and the use of medicinal plants, particularly celery, in damage to be effective. The aim of this study is to investigate the changes in matrix metalloproteinases 2,9 (MMP 2,9) and tissue inhibitor of matrix metalloproteinase 1 (TIMP-1) with synchronized exercise training and herbal supplementation with celery in overweight women. Methods: We randomly divided 28 overweight women into four groups: exercise, supplement, exercise–supplement, and control. Pilates training was performed for three sessions per week, for 60 minutes per session. Celery was administered at a dose of 3900 g per day in 3 capsules as a supplement. Blood sampling was performed before and 48 h after the last intervention. The analysis was performed by a paired t-test and one way analysis of variance (p≤0.05). Results: After eight weeks, the levels of MMP-2, MMP-9 and body weight decreased and TIMP-1 increased in the exercise, supplement, and exercise–supplement groups (p<0.05). A significant difference was observed between the groups. Conclusion: The results showed that Pilates training and celery each, separately, had positive effects on MMP-2, MMP-9 and TIMP-1 in overweight women. However, the simultaneous effect of exercise and supplementation led to better efficiency.

The Killing effect of Silver Nanoparticles and Direct Electric Current Induction on Leishmania major Promastigotes In Vitro

Abstract: 1M.Sc., Department of Parasitology and Entomology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 2Professor, Department of Parasitology and Entomology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 3Ph.D. Candidate, Department of Parasitology and Entomology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 4M.Sc. Student, Department of Electrical Power Engineering, Saveh Branch of Islamic Azad University, Saveh, Iran

Effects of High Fat Diet and High Intensity Aerobic Training on Interleukin 6 Plasma Levels in Rats

Abstract: Objective : Interleukin 6 (IL6) is a pro-inflammatory cytokine that plays an important role in obesity and related metabolic disorders. Also, exercise training has been offered in obesity prevention and immune system improvement. Hence, this study intends to survey the effects of high fat diet and high intensity aerobic training on plasma levels of IL6 in rats. Methods : We divided 28 male Wistar rats into two control groups with normal (CN) or high fat (CH) diet and two training groups with normal (EN) or high fat (EH) diet. The training groups ran for 60 minutes on a treadmill at 35 m/min for 5 days/week (75% VO2 max). After 8 weeks, we collected blood samples for plasma IL6 assessment. Two-way ANOVA was used for statistical analysis (P≤0.05). Results : The high fat diet significantly increased the rats’ weights and plasma IL6 levels. Performance of 8 weeks of high intensity aerobic training increased IL6 levels in the normal diet group and decreased IL6 levels in the high fat diet group. This change was not significant in the normal diet group. Conclusion: High fat diets probably induced inflammation due to elevated IL6 levels. High intensity aerobic training for 8 weeks significantly decreased IL6 levels.

Comparison of Two Different Immature Mouse Ovarian Vitrification Methods using Trypan Blue Staining

Abstract: Objective: Different cryoprotectants are used for cryopreservation of ovarian tissue in patients at risk of infertility. Ethylene glycol (EG), dimethyl sulfoxide (DMSO) and propanediol (PROH) have been chosen as the basic permeable cryoprotectants due to their decreased glass-formation characteristics compared to other cryoprotectants. In the present study, the effects of two different vitrification methods on whole mouse ovarian tissue by the use of a novel staining method (trypan blue) has been evaluated. Methods: Ovaries of 8 day-old NMRI mice were isolated and divided among the control, vitrification 1 (Vit1) and vitrification 2 (Vit2) groups. The Vit1 solution was composed of α-MEM+ 20% FBS + 15% EG + 15% DMSO. The Vit 2 solution was composed of αMEM+ 15% FBS +20% EG + 20% PROH. Vit1 and Vit2 procedures were performed at 4˚C and room temperature, respectively. Warming was performed in α-MEM+ 20% FBS supplemented with 1M sucrose in the Vit1 group and α-MEM+ 15% FBS with descending concentrations of sucrose (1, 0.5, 0.25 M) in the Vit2 group. Control and vitrified warmed ovaries were put in α-MEM supplemented by 0.4% trypan blue for 20 min, and then stained ovaries were fixed in Bouin’s fixative, serially sectioned in paraffin wax and finally quantitatively evaluated under a light microscope. Results: The highest percentage of primordial follicles was observed in the control group. There was a significant difference between the control and Vit1 groups, and between the Vit1 and Vit2 groups (p<0.05). No significant difference was observed in primary and preantral follicles between the control and vitrification groups. Conclusion: Vitrification with EG and PROH are more suitable for preservation of follicle reserves in ovaries. Trypan blue staining is a faster and easier method for evaluation of ovarian tissue.

Investigating the Stability of Polymer Coating of Methoxy Polyethylene Glycol Activated by Succinimidyl Valerate on the Surface of Red Blood Cells at In vitro and In vivo Conditions

Abstract: Objective : The host immune response against minor donor blood groups may be considered a significant problem in certain groups of patients that undergo transfusions such as those who require repeat transfusions (thalassemia). A proposed solution is to coat the surface antigens on red blood cells (RBCs) by covalent binding of methoxy polyethylene glycol (mPEG). This study aims to determine the storage time of PEGylated cells before injection and its effective time during in vivo conditions. Methods : We used mPEG activated by succinimidyl valerate (SVA) to PEGlayte the cells. The stability of the created coating during in vitro conditions was investigated by three methods: counting the numbers of free cells, flow cytometry and qualitative investigation. The appropriate concentration of mPEG for rabbit RBC PEGylation was determined by electron microscopy. The effective time of PEGylated rabbit RBCs was determined with flow cytometric analysis after the injection. In addition, we investigated the serum biochemical properties at 24 hours after the injection. Results : The appropriate concentration of 15 mg/mL for rabbit RBC PEGylation was determined. At 48 hours after injection, 83% of the cells that were alive in the host circulatory system kept their polymeric coating. Conclusion: We determined that 18 days was an appropriate storage time for PEGylated RBCs under in vitro conditions. The effective time of 14 days was determined for PEGylated RBCs by tracking the cells in vivo. An investigation of the serum biochemical properties of rabbits at 24 hours after the injection showed that the RBC coating significantly inhibited stimulation of the host immune system and cell destruction.

Immobilization of Organophosphorus Hydrolase on the Surface of Bacillus subtilis Spores by the Adsorption Method

Abstract: 1PhD. Candidate, Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran 2Professor, Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 3Assistant Professor, Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran 4Associated Professor, Department of Biotechnology, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology, Kerman, Iran

Identification of Novel targeting peptides for PC3 cells by the screening of a phage display peptide library

Abstract: Objective : Prostate cancer is the second cause of cancer-associated death in men. In recent years, targeted therapy for cancer has attracted the attention of researchers. Targeted therapy leads to a decrease in drug adverse effects. Studies indicate that targeting peptides for cancer cells represent valuable tools for diagnostics and therapeutics. Recently, phage display peptide libraries have been used to identify target peptides to a variety of cancer cells. In the current study, we aim to isolate peptides that target PC3 cells (human prostate adenocarcinoma cells). Methods: Four rounds of subtractive panning on control cells that included 5637 (bladder), Huh-7 (liver), SW480 (colon), AGS (stomach) and human fibroblast normal in addition to four rounds of positive panning on PC3 (target cell) were performed. Polyclonal phage ELISA was used to evaluate the process of enrichment during biopanning. Subsequently, phage clones were randomly selected from titer plates, amplified by plaque-PCR, and their genomic DNA was sequenced. We conducted bioinformatic analysis for further characterization of the isolated peptides. Results: Several rounds of panning resulted in the enrichment of a number of peptides. The results of polyclonal phage ELISA indicated that the biopanning process was successful. In silico analysis showed the presence of several consensus amino acid motifs in the peptides. Conclusion: The peptides identified through biopanning can be considered as potential specific binders to PC3 cells. Peptides with specificity binding to target cells can be used for targeted gene and drug delivery to malignant tumor cells. Further analyses of these peptides are required to show their capacity for targeted delivery of various genes and drugs into prostate cancer cells.

Identification and Discovery of Novel microRNAs in the Human Genome

Abstract: Although more than 98% of the human genome is transcribed, most of these transcripts are not translated into proteins. Rather, they are considered as non-coding RNAs. MicroRNAs (miRNAs) are very short non-coding RNAs approximately 22 nucleotides in length which regulate many key processes of cells such as growth, proliferation, differentiation, cell cycle, apoptosis (programmed cell death) and metabolism. On the other hand, it is known that these small regulatory molecules are involved in many human diseases such as different cancers and cardiovascular disorders. Therefore, discovery and functional characterization of novel miRNAs is a prominent achievement. Low abundance and spatiotemporal expression of these mediator molecules make their discovery difficult by conventional methods. Therefore, bioinformatics software have been designed for the prediction of stem-loop structures capable of producing miRNA precursors in the human genome. On the other hand, there are several bioinformatics tools for prediction of miRNA target genes. Prediction of miRNA target genes helps to characterize the function of a miRNA. In this paper, we have reviewed some of the common efficient bioinformatics tools and experimental approaches used for prediction and identification of the miRNA genes and their target genes.

A comparison of the effect of vitrification on the morphology of stimulated and non-stimulated human ovaries

Abstract: Objective : This study aimed to evaluate the effect of vitrification on the morphology of human ovarian tissue in a stimulated group compared to a non-stimulated group. Methods : Ovarian cortex biopsies collected from stimulated and non-stimulated groups were transported to the laboratory in L-15 medium. Biopsies were cut into small pieces and divided randomly into the vitrified and non-vitrified subgroups. The vitrified-warmed and fresh samples were fixed using Bouin’s solution, then passaged, sectioned and stained with hematoxylin and eosin and Masson’s trichrome. The follicles at different developmental stages were counted and evaluated. Results : Morphological observations showed that the follicles and stromal tissue had well preserved normal structures after vitrification and warming. The percentage of normal follicles in the non-stimulated non-vitrified group was 89.22%; for the non-stimulated vitrified group, it was 84.60%. In previous groups the proportion of primordial follicles were 68.7 ± 1.60% and 67.80 ± 3.71%, primary follicles were 28.60 ± 1.72% and 29.40 ± 3.51%, and secondary follicles were 3.60 ± 0.66% and 2.70 ± 1.20%, respectively. The percentage of normal follicles in the stimulated non-vitrified group was 88.18%; for the stimulated vitrified group, it was 84.19%. In stimulated non-vitrified and stimulated vitrified groups the proportion of primordial follicles were 49.70 ± 4.13% and 49.34 ± 2.86%, primary follicles were 44.50 ± 3.83% and 44.72 ± 2.68%, and secondary follicles were 5.60 ± 0.72% and 5.91 ± 0.77%, respectively. There was no significant difference between the vitrified and non-vitrified and stimulated and non-stimulated groups. Conclusion: Vitrification had no harmful effect on the morphology of stimulated human ovarian tissue and stroma and ovarain tissue structure was similar to the non-stimulated group. This method could be a good alternative for fertility preservation.

Effect of HCV Core Protein on Expression of α-SMA in Human Stellate Cell, LX-2 Cell Line

Abstract: 1M.Sc. Student, Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 2Associated Professor, Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 3Assistant Professor, Gastroenterohepatology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran 4M.Sc., Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran

Investigation of the Dynamic Medium on Proliferation and Differentiation of Mesenchymal Stem Cells after Culturing on Electrospun PCL and PCL-nHA Nanofibers

Abstract: Objective: More similarity to in vivo may help to increase the proliferation and differentiation of cells at in vitro culture. The present study has investigated the effect of a dynamic culture medium and nano hydroxyapatite (nHA) presence on proliferation and differentiation of mesenchymal stem cells (MSCs) to bone cells using electrospun polycaprolactone (PCL) scaffolds. Methods: We prepared PCL and PCL-nHA scaffolds by electrospinning. After static culturing of the scaffolds with MSCs, the scaffolds, were divided into two groups of static and dynamic cultures. The dynamic culture scaffolds were placed on a shaker. Cell proliferation and differentiation at days 3, 7 and 14 were investigated by MTT, and the calcium and alkaline phosphatase assays. Results: The obtained results from the MTT assay on day 14 showed an increase of 1.1 times in cell proliferation in the dynamic culture compared to the static culture. During this period, the calcium content produced by cells in the dynamic culture at day 14 were 1.23 times higher for PCL scaffolds and 1.46 times higher for PCL-nHA scaffolds compared to the static culture. Alkaline phosphatase levels for the dynamic state PCL scaffold were 1.24 times more and for PCL-nHA scaffolds were 1.28 times more compared to the static culture at day 14. Conclusion: The obtained results from dynamic culture, showed higher proliferation and differentiation of stem cells to bone for both PCL and PCL-nHA scaffolds compared to the static culture. The amount of cell proliferation and differentiation in the scaffolds that contained nHA was more than scaffolds that did not have nHA.