共查询到20条相似文献,搜索用时 9 毫秒
1.
Kolenko VM Uzzo RG Dulin N Hauzman E Bukowski R Finke JH 《Apoptosis : an international journal on programmed cell death》2001,6(6):419-429
Alterations in intracellular Zn2+ concentrations are believed to play a crucial role in modulating apoptosis. The observation that Zn2+ deficiency can induce cell death both in vivo and in vitro has been attributed to the fact that exchange of Zn2+ for Ca2+ and Mg2+ within the nuclei may directly activate endogenous endonucleases therefore inducing DNA fragmentation independent of cytoplasmic factors. Here we show that the membrane-permeable zinc chelator, N,N,N-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN) induces translocation of cytochrome c from the mitochondrial intramembranous space into the cytosol in human peripheral blood T lymphocytes (PBL) with subsequent activation of caspases-3, -8, and -9. Pretreatment of T lymphocytes with caspase inhibitors Z-VAD.fmk or DEVD.fmk prevented DNA fragmentation in response to TPEN indicating that apoptosis triggered by zinc deficiency is entirely dependent on activation of caspase family members. The release of cytochrome c and activation of downstream caspases precedes changes in the mitochondrial transmembrane potential ( m). Therefore, cytoplasmic and mitochondrial events are critical to this process. 相似文献
2.
Anchordoquy JM Picco SJ Seoane A Anchordoquy JP Ponzinibbio MV Mattioli GA Peral García P Furnus CC 《Cell biology international》2011,35(6):593-597
The purpose of this study was to investigate the effect of Zn (zinc) concentration on CCs (cumulus cells) during in vitro maturation. For this purpose, DNA integrity of CCs by addition of different Zn concentrations [0 (control); 0.7 μg/ml (Zn1); 1.1 μg/ml (Zn2) and 1.5 μg/ml (Zn3)] to the culture medium was evaluated by comet assay. In addition, early apoptosis was analysed by annexin staining assay. CCs treated with Zn showed a significant decrease in the DNA damage in a dose‐dependent manner. Comet assay analysed for TM (tail moment) was significantly higher in cells cultured without Zn (control, P<0.01) with respect to cells treated with Zn (control: 5.24±16.05; Zn1: 1.13±5.31; Zn2: 0.10±0.36; Zn3: 0.017±0.06). All treatments were statistically different from the control (P=0.014 for Zn1; P<0.01 for Zn2 and Zn3). The frequency of apoptotic cells was higher in the control group (control: 0.142±0.07; Zn1: 0.109±0.0328; Zn2:0.102±0.013; Zn3: 0.0577±0.019). Statistical differences were found between control and Zn1 (P=0.0308), control and Zn2 (P=0.0077), control and Zn3 (P<0.0001), Zn1 and Zn3 (P<0.001) and Zn2 and Zn3 (P=0.0004). No differences were found between Zn1 and Zn2. In conclusion, low Zn concentrations increase DNA damage and apoptosis in CCs cultured in vitro. However, adequate Zn concentrations ‘protect’ the integrity of DNA molecule and diminish the percentage of apoptotic CC. 相似文献
3.
Bollo E Guglielmino R Sant S Pregel P Riondato F Miniscalco B Cornaglia E Nebbia C Dacasto M 《Cell biology and toxicology》2006,22(4):275-284
Triphenyltin acetate (TPTA), a triorganotin compound used in agriculture as a biocide, is immunotoxic in vivo and in vitro. The present study was undertaken to ascertain whether apoptosis might play a role in the TPTA toxicity in vitro. Mouse thymocyte primary cultures were exposed to 0, 4 and 8 μmol/L TPTA; methyl prednisolone (1 μmol/L) was used as a positive
control. Cell aliquots were harvested after 0, 1, 2, 4, and 8 h and the presence of early or late apoptotic phenomena was
checked by (a) morphological investigations; (b) spectrophotometric quantification of fragmented DNA and agarose gel electrophoresis;
(c) cell flow cytofluorometry, using an annexin V-FITC kit; and (d) detection of in situ apoptosis by a colorimetric detection kit (Titer-Tacs). TPTA cytotoxicity was also evaluated using the trypan blue dye exclusion
test. Morphological investigation indicated apoptosis and/or necrosis. After 8 h of incubation, cells exposed to 4 μmol/L
TPTA showed an increase in DNA fragmentation (on electrophoresis), which was confirmed by spectrophotometry (p < 0.05). Flow cytofluorometry pointed out an early (p < 0.05) increase of annexin V-positive (apoptotic) cells in TPTA-exposed flasks, whereas at least partly contradictory, results
were obtained with the Titer-Tacs kit. Overall, these results provide evidence that TPTA, at low concentrations (4 μmol/L)
induces early and late apoptotic phenomena, whereas cells exposed to the highest concentrations (8 μmol/L) are likely to undergo
necrosis rather than apoptosis. 相似文献
4.
Brambila E Munoz-Sanchez JL Waalkes MP Albores A 《Biological trace element research》2000,78(1-3):255-264
Early effects of experimental cholestasis on the homeostasis of zinc (Zn) and metallothionein (MT) were studied in rats which
had undergone bile duct ligation for 0, 3, 6, 9, 12, 16, 20, and 24 h. Transient increases in hepatic Zn levels were observed
at 9 h but returned to control values at 12 h. Serum Zn levels increased at 24 h. Cholestasis was confirmed by increased serum
alkaline phosphatase (AP) activity. MT increased at 3 h and reached a maximum level at 12 h and remained elevated even at
24 h after the onset of experimental cholestasis. No hepatocellular damage was detected according to the results of alanine
aminotransferase (ALT) activities in serum. These results shown that the increases in Zn observed in liver are related to
bile stagnation rather than to a hepatocellular damage and that increased MT occurs concurrently with increased hepatic Zn.
These observations suggest that the cellular levels of Zn in cholestasis is regulated by homeostatic mechanisms, of which
one could be mediated by MT. 相似文献
5.
《Journal of trace elements in medicine and biology》2014,28(4):465-469
A 90-day randomized, double-blind, placebo-controlled, pre-post trial was conducted in four groups of Indonesian children aged 12–24 months: placebo, probiotic, zinc, and a combination of probiotic and zinc (n = 12 per group). Microencapsulated Lactobacillus plantarum IS-10506 of dadih origin was supplemented at a dose of 1010 CFU/day as a probiotic. Zinc was supplemented as 20 mg zinc sulfate monohydrate (8 mg zinc elemental). Blood and stool samples were collected at baseline and at the end of the study period. Fecal sIgA was assessed by ELISA and serum zinc concentrations by ICP-MS. Fecal sIgA increased significantly in the probiotic group (30.33 ± 3.32 μg/g; p < 0.01) and in the combination probiotic and zinc group (27.55 ± 2.28 μg/g; p < 0.027), as compared with the placebo group (13.58 ± 2.26 μg/g). Changes in serum zinc concentrations in the combination probiotic and zinc group showed the highest elevation at the end of the study period. A combination of probiotic L. plantarum IS-10506 at a dose of 1010 CFU/day and 8 mg of elemental zinc supplementation showed a potential ability to improve the zinc status of pre-school children. Taken together, supplementation with the probiotic L. plantarum IS-10506 and zinc for 90 days resulted in a significantly increased humoral immune response, as well as improved zinc status, in young children. 相似文献
6.
Effect of gypsum,pressmud, fulvic acid and zinc sources on yield and zinc uptake by rice crop in a saline-sodic soil 总被引:1,自引:0,他引:1
Summary The application of fulvic acid to a saline-sodic soil augmented the solubility of zinc by thousands fold. Zinc fulvate when applied at levels equivalent to that of zinc sulphate was more effective in enhancing diffusion of zinc in the soil. Application of gypsum, zinc sulphate and fulvic acid significantly increased dry matter yield and uptake of zinc by rice crop in a saline-sodic soil. Application of gypsum with pressmud or with fulvic acid and zinc sulphate resulted in significantly higher yield and zinc uptake than in other treatments. 相似文献
7.
Sun JY Jing MY Weng XY Fu LJ Xu ZR Zi NT Wang JF 《Biological trace element research》2005,107(2):153-165
Zinc (Zn) is an essential nutrient that is required in humans and animals for many physiological functions, including immune
and antioxidant function, growth, and reproduction. The present study was performed to investigate the effects of three Zn
levels, including Zn adequate (35.94 mg/kg, as a control), Zn deficiency (3.15 mg/kg), and Zn overload (347.50 mg/kg) in growing
male rats for 6 wk. This allowed for evaluation of the effects that these Zn levels might have on body weight, organ weight,
enzymes activities, and tissues concentrations of Zn and Cu. The results showed that Zn deficiency has negative effects on
growth, organ weight, and biological parameters such as alkaline phosphatase (ALP) and Cu−Zn superoxide dismutase (Cu−Zn SOD)
activities, whereas Zn overload played an effective role in promoting growth, improving the developments of organs and enhancing
immune system. Hepatic metallothionein (MT) concentration showed an identical increase tendency in rats fed both Zn-deficient
and Zn-overload diets. The actual mechanism of reduction of Cu concentration of jejunum in rats fed a Zn-overload diet might
involve the modulation or inhibition of a Cu transporter protein by Zn and not by the induction of MT. 相似文献
8.
The element Zn is the metal component or activator of many important enzymes. The tissue concentrations and activities of
Zn metalloenzymes direct the rate of protein and nucleic acid syntheses, thereby influencing tissue growth and reperative
processes. Most of the serum Zn is normally bound to circulating proteins. Low serum Zn concentrations might result from depletion
of Zn-binding proteins. Serum protein and Zn concentrations have been reported to be depressed in patients with acute and
chronic diseases. We compare the serum protein and Zn values of patients with thoracic empyema (n=20) with those of a control group (n=20). The values obtained in the empyema group were significantly lower than those in the control group before the study.
Test group administered 220 mg zinc sulfate (ZnSO4. 7H2O) over 20 d and there was a significant increase in the values for serum protein and Zn after the oral administration of
the zinc sulfate. 相似文献
9.
Henri Faure Alain Favier Michele Tripier Josiane Arnaud 《Biological trace element research》1990,24(1):25-37
In this paper we report a method for measuring ultrafiltrable zinc in human serum by electrothermal atomic absorption spectrophtometry.
We show also that ultrafiltration permits to determine alpha-2 macroglobulin bound zinc and losely bound zinc if a strong
zinc ligand (EDTA) is added to serum before ultrafiltration. This last fraction, after deduction of ultrafiltrable zinc, represents
roughly all albumin bound zinc. In 20 controls we found that ultrafiltrable zinc amounted 0.311 μmol/L (S.D.=0.117 μmol/L),
alpha-2 macroglobulin bound zinc 3.08 μmol/L (S.D.=0.221 μmol/L), and albumin bound zinc 12.11 μmol/L (S.D.=1.95 μmol/L).
Our method needs only a small volume of serum, it is simple and rapid but also very accurate and reliable. The losely bound
fraction is very dynamic and, representing the physiologically active part of serum zinc, it could be a good marker of zinc
deficiency. 相似文献
10.
锌对缺血/再灌注肝脏自由基含量和细胞凋亡的影响 总被引:2,自引:0,他引:2
目的:观察补锌对缺血再灌注(HIR)大鼠肝脏自由基含量及细胞凋亡的影响。探讨补锌保护肝损伤的机制。方法:用荧光分光光度法测定血清MDA含量;用电子自旋共振法测定肝脏自由基浓度;用流式细胞术检测肝细胞凋亡。结果:HIR组大鼠血清MDA水平和肝自由基产生均增加,补锌后降低;肝脏缺血再灌注后肝细胞凋亡率达到57.72%,补锌后降低40.85%。结论:减少自由基产生和抑制细胞凋亡是锌保护肝缺血再灌注损伤的重要机制。 相似文献
11.
Apoptosis plays an essential role in T cell biology. Thymocytes expressing nonfunctional or autoreactive TCRs are eliminated by apoptosis during development. Apoptosis also leads to the deletion of expanded effector T cells during immune responses. The dysregulation of apoptosis in the immune system results in autoimmunity, tumorogenesis and immunodeficiency. Two major pathways lead to apoptosis: the intrinsic cell death pathway controlled by Bcl-2 family members and the extrinsic cell death pathway controlled by death receptor signaling. These two pathways work together to regulate T lymphocyte development and function. 相似文献
12.
We studied the sensitivity of tumor cells to the induction of apoptosis by iron deprivation. Iron deprivation was achieved by the employment of a defined iron-deficient culture medium. Mouse 38C13 cells and human Raji cells die within 48 and 96 h of incubation in iron-deficient medium, respectively. On the contrary, mouse EL4 cells and human HeLa cells are completely resistant to the induction of death under the same experimental arrangement. Deoxyribonucleic acid fragmentation analysis by agarose gel electrophoresis as well as flow cytometric analysis after propidium iodide staining detected in 38C13 and Raji cells, but not in EL4 and HeLa cells, changes characteristic to apoptosis. The 38C13 cells, sensitive to iron deprivation, also displayed a similar degree of sensitivity to apoptosis induction by thiol deprivation (achieved by 2-mercaptoethanol withdrawal from the culture medium) as well as by rotenone (50 nM), hydroxyurea (50 microM), methotrexate (20 nM), and doxorubicin (100 nM). Raji cells shared with 38C13 cells a sensitivity to rotenone, methotrexate, doxorubicin, and, to a certain degree, to hydroxyurea. However, Raji cells were completely resistant to thiol deprivation. EI4 and HeLa cells, resistant to iron deprivation, also displayed a greater degree of resistance to most of the other apoptotic stimuli than did their sensitive counterparts. We conclude that some tumor cells in vitro are sensitive to apoptosis induction by iron deprivation, while other tumor cells are resistant. All the tumors found to be sensitive to iron deprivation in this study (four cell lines) are of hematopoietic origin. The mechanism of resistance to apoptosis induction by iron deprivation differs from the mechanism of resistance to thiol deprivation. 相似文献
13.
Jablonski EM Hughes FM 《Biology of the cell / under the auspices of the European Cell Biology Organization》2006,98(1):33-42
BACKGROUND INFORMATION: During apoptosis, the first morphological change is a distinct cell shrinkage known as the AVD (apoptotic volume decrease). This event is driven by a loss of intracellular K(+), which creates an osmotic gradient, drawing water out of the cell through AQPs (aquaporins). Loss of water in balance with K(+) would create a shrunken cell with an equivalent intracellular concentration of K(+) ([K(+)](i) = 140 mM). However, we have previously shown that the [K(+)](i) of the shrunken apoptotic cell is 35 mM, and this level is absolutely essential for the activation of apoptotic enzymes. We have recently found that AQPs are inactivated following the AVD, so that continued loss of K(+) will reduce the intracellular concentration to this critical level. Using thymocytes, we have investigated the expression profile and regulation of the AQP family members. RESULTS: In the present study, we have found that AQP1, AQP8 and AQP9 are present in non-apoptotic thymocytes and localized primarily to the plasma membrane. Expression and localization did not change when these cells were induced to undergo apoptosis by growth factor withdrawal for 24 h. To explore other possible mechanisms by which these water channels are inactivated, we investigated their association with CAV-1 (caveolin-1), binding to which is known to inactivate a variety of proteins. We found that CAV-1 is present in thymocytes and that this protein co-localizes with a portion of AQP1 in normal (non-apoptotic) thymocytes. However, thymocytes induced to undergo apoptosis greatly increase their AQP1/CAV-1 association. CONCLUSIONS: Taken together, these results indicate that AQPs are localized to the plasma membrane of shrunken apoptotic thymocytes where increased binding to CAV-1 potentially inactivates them. AQP inactivation, coupled with continued K(+) efflux, then allows the [K(+)](i) to decrease to levels conducive for the activation of downstream apoptotic enzymes and the completion of the apoptotic cascade. 相似文献
14.
Yan G. Zorbas Yuri N. Yaroshenko Nikolai K. Kuznetsov Alexei L. Ivamov 《Biological trace element research》1997,60(1-2):101-113
The objective of this investigation was to evaluate the effect of 47 mg zinc supplementation on deficiency of zinc in rats
during 98 d of restriction of motor activity (hypokinesia), which appeared by higher plasma zinc concentration.
One Hundred 13-week-old Sprague-Dawley male rats weighing 360–390 g were used to perform the studies: They were equally divided
into four groups: 1. Unsupplemented control animals (UCA); 2. Unsupplemented hypokinetic animals (UHA); 3. Supplemented control
animals (SCA); and 4. Supplemented hypokinetic animals (SHA). For the simulation of the effect of hypokinesia (HK), the UHA
and SHA were kept in small individual cages made of wood, which restricted their movements in all directions without hindering
food and water intake. The SCA and SHA received daily with their food an additional amount of zinc.
Before and during the experimental period of 98 d, plasma, urinary and fecal zinc, balance of zinc, food intake, and body
weight were determined at different intervals. In the SHA and UHA, the concentration of zinc in plasma, and the elimination
of zinc in urine and feces increased significantly when compared with the SCA and UCA, whereas the balance of zinc was negative.
The body weight and food intake decreased significantly in the SHA and UHA when compared with the SCA and UCA. The increased
plasma concentration of zinc in both the SHA and UHA groups was in contrast to the observed hypozincnemia during prolonged
immobilization as during prolonged hospitalization. This reaction suggests that there may be some other mechanisms that are
affecting the process of control and regulation of zinc metabolism during prolonged HK.
It was concluded that exposure to prolonged restriction of motor activity of rats induces significant increases in plasma
concentration, fecal and urinary elimination of zinc in the presence of negative zinc balance and regardless the daily intake
of large amounts of zinc with their food, leading to zinc deficiency. 相似文献
15.
目的 观察不同浓度氟化钠对睾丸间质细胞增殖和细胞凋亡的影响,为氟中毒的机制研究提供依据.方法 取体外培养的睾丸间质细胞,胰酶消化后制成单细胞悬液,常规培养,待细胞融合率达80%,且未出现细胞分化时,将细胞分4组,加入不同浓度的氟化钠染毒(0,5,10,20 mg/L)睾丸间质细胞,分别干预0,24,48,72,96,1... 相似文献
16.
The objective of the study was to explore the changes in melatonin and zinc levels in rats with induced hypothyroidism. Thirty adult male rats used in the study were allocated to three groups with equal numbers. Group 1: General control group which was not subjected to any procedure. Group 2: Sham-hypothyroidism group to which was administered 10 mg kg(-1) intraperitoneal (i.p.) physiologic saline (0.09% NaCl) for 4 weeks. Group 3: Hypothyroidism group which was supplemented with intraperitoneal 10 mg kg(-1) propylthiouracil (PTU) for 4 weeks. Blood samples collected from all animals at the end of the study by decapitation were analysed for serum Total T4 (TT4), Total T3 (TT3), Free T4 (FT4), Free T3 (FT3) (ELISA) as well as for melatonin (RIA) hormones and zinc levels (atomic emission). Comparison of the study groups in terms of thyroid hormones, melatonin and zinc levels showed that TT4, TT3, FT4, FT3, melatonin and zinc levels in group 3 were lower than those in groups 1 and 2 (p < 0.01). These parameters were not different in groups 1 and 2. The results of the study demonstrate that PTU supplementation for 4 weeks results in a significant inhibition in both melatonin and zinc levels. Inhibited melatonin levels may result from the decrease in zinc levels. 相似文献
17.
Effect of different selenium sources and levels on porcine circovirus type 2 replication in vitro. 总被引:1,自引:0,他引:1
Qunxing Pan Kehe Huang Kongwang He Fuzeng Lu 《Journal of trace elements in medicine and biology》2008,22(2):143-148
Porcine circovirus type 2 (PCV2) has been linked to several disease syndromes during the last decade. A deficiency in selenium has also been associated with the increases of virulence of some viruses and severity of infectious disease. In order to evaluate the effect of different selenium sources and levels on PCV2 replication in PK-15 cells, three selenium sources, i.e. sodium selenite, kappa-selenocarrageenan and dl-selenomethionine at concentrations of 0, 2, 4, 8, and 16 micromol/L were used throughout this experiment. PCV2 loads in PK-15 cells were measured by a newly developed real-time quantitative PCR. A significantly inhibitive effect of dl-selenomethionine on PCV2 replication in vitro was demonstrated and the inhibition was concentration dependent within the range of 2-16 micromol/L. The inhibitive effect of dl-selenomethionine on PCV2 replication may be caused by enhanced activity of glutathione peroxidase. Our results may serve as a basis for further studies of the biological function of selenium and control of PCV2 infection. 相似文献
18.
ObjectivesZinc, which is found in high concentrations in the β-cells of the pancreas, is also a critical component for the endocrine functions of the pancreas. SLC30A8/ZnT8 is the carrier protein responsible for the transport of zinc from the cytoplasm to the insulin granules. The aim of this study was to investigate how dietary zinc status affects pancreatic beta cell activation and ZnT8 levels in infant male rats born to zinc-deficient mothers.MethodsThe study was performed on male pups born to mothers fed a zinc-deficient diet. A total of 40 male rats were divided into 4 equal groups. Group 1: In addition to maternal zinc deficiency, this group was fed a zinc-deficient diet. Group 2: In addition to maternal zinc deficiency, this group was fed a standard diet. Group 3: In addition to maternal zinc deficiency, this group was fed a standard diet and received additional zinc supplementation. Group 4: Control group. Pancreas ZnT8 levels were determined by ELISA method and insulin-positive cell ratios in β-cells by immunohistochemistry.ResultsThe highest pancreatic ZnT8 levels and anti-insulin positive cell ratios in the current study were obtained in Group 3 and Group 4. In our study, the lowest pancreatic ZnT8 levels were obtained in Group 1 and Group 2, and the lowest pancreatic anti-insulin positive cell ratios were obtained in Group 1.ConclusionThe results of the present study; in rats fed a zinc-deficient diet after maternal zinc deficiency has been established shows that ZnT8 levels and anti-insulin positive cell ratios in pancreatic tissue, which is significantly suppressed, reach control values with intraperitoneal zinc supplementation. 相似文献
19.
A perturbation of zinc metabolism has been noted in subjects with obesity. Zinc may also participate in the intracellular
signal cascade by affecting cellular calcium influx and a change in the calcium-calmodulin (CaM)-cyclic adenosine monophosphate
(cAMP) pathway. The possible effects of zinc on cellular concentrations of CaM, a major cytosolic calcium-binding protein,
in the adipocytes derived from obese (ob/ob) mice and their lean counterparts were studied. Adipocytes derived from both phenotypes
of mice were treated either with 0.2 mM of zinc sulfate or without any additive for 1 h of incubation; the cellular levels of CaM and cAMP were then determined.
The results showed that the obese mice had lower CaM and cAMP levels in their adipocytes compared to the lean mice. Zinc treatment
reduced CaM and increased cAMP levels in all mice, although this effect was more pronounced in the lean mice. This study indicated
that there was an inverse interaction between CaM and cAMP in their cellular levels in the mouse adipocytes and that might
be affected by exogenous zinc addition. 相似文献
20.
Kiran Bharti Neha Pandey Deepti Shankhdhar P. C. Srivastava S. C. Shankhdhar 《Physiology and Molecular Biology of Plants》2014,20(1):41-48
A field study was carried out to investigate the effect of three Zn levels 0, 20 kg ZnSO4 ha−1 and 20 kg ZnSO4 ha−1+ foliar spray of 0.5 % ZnSO4 on superoxide dismutase activity, acid phosphatase activity and grain yield and a pot experiment to study the effect of zinc deficient and sufficient conditions on organic acid exudation. Increasing Zn levels was established as beneficial in improving the enzyme activities of genotypes. Combined foliar and soil application of Zn proved to be superior of all the treatments. Zinc application resulted in a maximum increment limit of 96.8 % in superoxide dismutase activity, 75.76 % in acid phosphatase activity, and a decrement limit of 88.57 % in oxalic acid exudation irrespective of stages and year of study. The increased enzyme activities had a positive impact on grain yield. As an average of all genotypes an improvement of 19.88 % in 2009 and 21.29 % in 2010 due to soil application while of 16.45 % in 2009 and 13.01 % in 2010 due to combined application was calculated for grain yield. There existed a variation among genotypes in showing responses towards zinc application and the genotypes UP 2584 and PBW 550 were found to be more responsive. 相似文献