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Lithium preparations are commonly used drug in treating mental disorders and bipolar diseases, but metal's cytotoxic mechanisms have not yet been completely understood. In this study, we investigated the cytotoxic mechanisms of lithium in freshly isolated rat hepatocytes. Lithium cytotoxicity were associated with reactive oxygen species (ROS) formation and collapse of mitochondrial membrane potential and cytochrome c release into the hepatocyte cytosol. All of the mentioned lithium-induced cytotoxicity markers were significantly (P?0.05) prevented by ROS scavengers, antioxidants, mitochondrial permeability transition pore sealing agents and adenosine triphosphate generators. Hepatocyte glutathione (GSH) was also rapidly oxidized and GSH-depleted hepatocytes were more resistant to lithium-induced oxidative stress markers. This suggests that lithium is activated by GSH. Our results also showed that CYP2E1 is involved in lithium oxidative stress mechanism. Lithium cytotoxicity was also associated with mitochondrial injuries initiated by increased ROS formation resulted from metal-CYP2E1 destructive interaction or metal-induced disruption of mitochondrial electron transfer chain. Methyl donors such as betaine, methionine, or folic acid prevented lithium cytotoxicity, and this suggests that this metal is detoxified by phase II metabolic methylation. In conclusion lithium-induced cytotoxicity could be attributed to oxidative stress and mitochondrial dysfunction. 相似文献
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Sherafat MA Javan M Mozafari S Mirnajafi-Zadeh J Motamedi F 《Neurochemical research》2011,36(10):1887-1895
Multiple sclerosis (MS) is a demyelinating disease that affects the central nervous system. MS is the most common neurological
disorder in young adults with a greater incidence among females. Male gonadal hormones have a protective effect on neural
system development and myelin maturation. In this study, we investigate the effect of castration on lysolecithin-induced demyelination
and remyelination processes using visual evoked potentials, in addition to measuring the expressions of Olig2, MBP, Nogo-A
and GFAP mRNAs as oligodendrocyte or astrocyte markers; and histological assessments by myelin-specific staining. We observed
more expanded demyelination with delayed repair process in castrated rats. Expression levels of the aforementioned marker
genes confirmed histological and electrophysiological observations. Our results showed a pivotal role for endogenous male
hormones in the context of demyelinating insults. It may also account for the different prognosis of MS between male and female
genders and provide new insights for therapeutic treatments. 相似文献
5.
Javad Sajedianfard Zahra Behroozi Saeed Nazifi Hamid Rajaian 《International journal of peptide research and therapeutics》2013,19(2):93-98
The effect of oral administration of different doses of hydroalcoholic extract of silymarin on body weight, glucose concentration and indicators of oxidative stress superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and malondialdehyde (MDA) was investigated in the present study. Fifty adult male Wistar rats were used. The animals were divided into five groups and oral route of administration was used in control group (0.9 %, NaCl), control group patients (0.9 %, NaCl), diabetic group (100 mg/kg, silymarin), diabetic group (125 mg/kg, silymarin), diabetic group (250 mg/kg, silymarin) for 14 days with gavage. Diabetes was induced by a single injection of streptozotocin (45 mg/kg, i.p.). Before and 3 days after injection, and at 7 and 14 days of treatment, the fasting glucose level and weight were measured. At the end of 14 days, animals were anesthetized with ether and blood samples were taken by heart puncture and were analyzed for oxidative stress indicators. The results showed that hydroalcoholic extract of silymarin can increase the average body weight and decrease glucose and, at the end of 14 days, decrease MDA level and increase the level of antioxidant enzymes (SOD, GPX, CAT) in red blood cells in a dose-dependent manner (P < 0.05). In conclusion, the hydroalcoholic extract of silymarin has an overall beneficial effect on body weight, glucose level and oxidative stress. Therefore, silymarin may reduce oxidative stress via increasing antioxidant enzyme activity. 相似文献
6.
Seána Duggan Fabian Essig Kerstin Hünniger Zeinab Mokhtari Laura Bauer Teresa Lehnert Susanne Brandes Antje Häder Ilse D. Jacobsen Ronny Martin Marc Thilo Figge Oliver Kurzai 《Cellular microbiology》2015,17(9):1259-1276
Candida albicans and Candida glabrata account for the majority of candidiasis cases worldwide. Although both species are in the same genus, they differ in key virulence attributes. Within this work, live cell imaging was used to examine the dynamics of neutrophil activation after confrontation with either C. albicans or C. glabrata. Analyses revealed higher phagocytosis rates of C. albicans than C. glabrata that resulted in stronger PMN (polymorphonuclear cells) activation by C. albicans. Furthermore, we observed differences in the secretion of chemokines, indicating chemotactic differences in PMN signalling towards recruitment of further immune cells upon confrontation with Candida spp. Supernatants from co‐incubations of neutrophils with C. glabrata primarily attracted monocytes and increased the phagocytosis of C. glabrata by monocytes. In contrast, PMN activation by C. albicans resulted in recruitment of more neutrophils. Two complex infection models confirmed distinct targeting of immune cell populations by the two Candida spp.: In a human whole blood infection model, C. glabrata was more effectively taken up by monocytes than C. albicans and histopathological analyses of murine model infections confirmed primarily monocytic infiltrates in C. glabrata kidney infection in contrast to PMN‐dominated infiltrates in C. albicans infection. Taken together, our data demonstrate that the human opportunistic fungi C. albicans and C. glabrata are differentially recognized by neutrophils and one outcome of this differential recognition is the preferential uptake of C. glabrata by monocytes. 相似文献
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Alamtaj Samsami Dehaghani Khatere Shahriary Mohammad Amin Kashef Sirous Naeimi Mohammad Javad Fattahi Zahra Mojtahedi Abbas Ghaderi 《Molecular biology reports》2009,36(8):2393-2397
IL-18, initially defined as a potent inducer of IFN- γ production, is a systemic, multifunctional cytokine with both pro-cancerous
and anti-cancer activities. The contribution of the IL-18 promoter polymorphisms at positions −607 (C/A) and −137 (G/C) to
cancer development has been reported. We sought to examine IL-18 serum level and its polymorphisms in Iranian women with ovarian
cancer. Single nucleotide polymorphisms (SNPs) at positions −607 (C/A) and −137 (G/C) were analyzed by allele-specific polymerase
chain reaction in 85 women with ovarian cancer and 158 healthy controls. IL-18 serum level was determined using ELISA method.
No significant association was found between the allele, genotype, and haplotype distributions of the SNPs and ovarian cancer.
Mean IL-18 serum level was significantly higher in patients than in controls (P = 0.008). Comparing IL-18 serum levels with genotypes at positions −607 and −137 revealed no significant difference. No association
was also found between IL-18 levels and the disease stage. In conclusion, our results indicate that IL-18 promoter polymorphisms
at positions −607 (C/A) and −137 (G/C) appear not to confer susceptibility to ovarian cancer in Iranian population; however,
IL-18 serum level increases in ovarian cancer patients. 相似文献
8.
Zhen-Yong Keck Sven G. Enterlein Katie A. Howell Hong Vu Sergey Shulenin Kelly L. Warfield Jeffrey W. Froude Nazli Araghi Robin Douglas Julia Biggins Calli M. Lear-Rooney Ariel S. Wirchnianski Patrick Lau Yong Wang Andrew S. Herbert John M. Dye Pamela J. Glass Frederick W. Holtsberg Steven K. H. Foung M. Javad Aman 《Journal of virology》2016,90(1):279-291
9.
Amoli MM Amiri P Alborzi A Larijani B Saba S Tavakkoly-Bazzaz J 《Molecular biology reports》2012,39(9):8595-8599
To assess the expression of vascular endothelium growth factor (VEGF) mRNA in unstimulated peripheral blood mononuclear cells of patients with and without coronary artery disease (CAD). We also studied whether the functional VEGF -2,578C/A polymorphism may influence the level of VEGF mRNA expression in individuals undergoing coronary angiography because chest pain. We assessed 50 consecutive patients with angiographically confirmed CAD (CAD+). Also, 50 consecutive individuals with normal coronary studies were included in the study for comparison. VEGF mRNA expression was examined using quantitative real-time PCR and genotyping for VEGF -2,578C/A was performed using ARMS-PCR technique. VEGF mRNA expression was significantly decreased in CAD+ patients when compared to CAD- individuals (p = 0.01). The frequency of VEGF -2578 allele C and genotype CC was increased in CAD+ patients. In this regard, homozygosity for the CC genotype was more commonly observed in CAD+ (30 %) than in those without CAD disease (18 %). However, the difference was slightly out of the range of significance (p = 0.1). In addition, a trend for reduction in the expression of VEGF mRNA was observed when patients carrying the VEGF -2,578AA genotype were compared with those VEGF -2,578AC heterozygous or those homozygous for the VEGF -2,578CC genotype. VEGF gene expression is decreased in individuals with CAD+ disease. The VEGF -2,578C/A polymorphism may influences the expression of VEGF. 相似文献
10.
Fatemeh Mokhtari‐Jafari Ghassem Amoabediny Nooshin Haghighipour Reza Zarghami Alireza Saatchi Javad Akbari Nasim Salehi‐Nik 《Engineering in Life Science》2016,16(3):290-298
Tissue engineering, an immensely important field in contemporary clinical practices, aims at the repair or replacement of damaged tissues. The mathematical model proposed herein shows the distribution and growth of cells in their characteristic time in a 3D scaffold model. This study contributes to the progress of simulation techniques in static and dynamic cultures of bone tissue. Brinkman, nutrient transport, and cell growth equations are brought together to quantify the growth behavior of cells. However, when a static culture is being studied, the Brinkman equation is eliminated. The model was validated by experimental cell culture using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay and scanning electron microscopy. Then, static and dynamic cultures were compared to assess the cell density and cell distribution in the scaffold. Cell counting after 21 days of cell culture showed that the number of cells increased 42‐fold in static and 53.5‐fold in dynamic cultures, which was in good agreement with our model estimations (37‐fold increase in the number of cells in static and 49‐fold increase in dynamic cultures). In conclusion, our mathematical model could predict cell distribution and growth in the scaffold. 相似文献