Bcl-2 Content Research Articles

Inhibition of Bcl-2 sensitizes mitochondrial permeability transition pore (MPTP) opening in ischemia-damaged mitochondria.

BackgroundMitochondria are critical to cardiac injury during reperfusion as a result of damage sustained during ischemia, including the loss of bcl-2. We asked if bcl-2 depletion not only leads to selective permeation of the outer mitochondrial membrane (MOMP) favoring cytochrome c release and programmed cell death, but also favors opening of the mitochondrial permeability transition pore (MPTP). An increase in MPTP susceptibility would support a role for bcl-2 depletion mediated cell death in the calcium overload setting of early reperfusion via MPTP as well as later in reperfusion via MOMP as myocardial calcium content normalizes.MethodsCalcium retention capacity (CRC) was used to reflect the sensitivity of the MPTP opening in isolated cardiac mitochondria. To study the relationship between bcl-2 inhibition and MPTP opening, mitochondria were incubated with a bcl-2 inhibitor (HA14-1) and CRC measured. The contribution of preserved bcl-2 content to MPTP opening following ischemia-reperfusion was explored using transgenic bcl-2 overexpressed mice.ResultsCRC was decreased in mitochondria following reperfusion compared to ischemia alone, indicating that reperfusion further sensitizes to MPTP opening. Incubation of ischemia-damaged mitochondria with increasing HA14-1concentrations increased calcium-stimulated MPTP opening, supporting that functional inhibition of bcl-2 during simulated reperfusion favors MPTP opening. Moreover, HA14-1 sensitivity was increased by ischemia compared to non-ischemic controls. Overexpression of bcl-2 attenuated MPTP opening in following ischemia-reperfusion. HA14-1 inhibition also increased the permeability of the outer membrane in the absence of exogenous calcium, indicating that bcl-2 inhibition favors MOMP when calcium is low.ConclusionsThe depletion and functional inhibition of bcl-2 contributes to cardiac injury by increasing susceptibility to MPTP opening in high calcium environments and MOMP in the absence of calcium overload. Thus, ischemia-damaged mitochondria with decreased bcl-2 content are susceptible to MPTP opening in early reperfusion and MOMP later in reperfusion when cytosolic calcium has normalized.

Tanshinone IIA therapeutically reduces LPS-induced acute lung injury by inhibiting inflammation and apoptosis in mice

To study the effects of tanshinone IIA (TIIA) on lipopolysaccharide (LPS)-induced acute lung injury in mice and the underlying mechanisms. Mice were injected with LPS (10 mg/kg, i.p.), then treated with TIIA (10 mg/kg, i.p.). Seven hours after LPS injection, the lungs were collected for histological study. Protein, LDH, TNF-α and IL-1β levels in bronchoalveolar lavage fluid (BALF) and myeloperoxidase (MPO) activity in lungs were measured. Cell apoptosis and Bcl-2, caspase-3, NF-κB and HIF-1α expression in lungs were assayed. LPS caused marked histological changes in lungs, accompanied by significantly increased lung W/D ratio, protein content and LDH level in BALF, and Evans blue leakage. LPS markedly increased neutrophil infiltration in lungs and inflammatory cytokines in BALF. Furthermore, LPS induced cell apoptosis in lungs, as evidenced by increased TUNEL-positive cells, decreased Bcl-2 content and increased cleaved caspase-3 content. Moreover, LPS significantly increased the expression of NF-κB and HIF-1α in lungs. Treatment of LPS-injected mice with TIIA significantly alleviated these pathological changes in lungs. TIIA alleviates LPS-induced acute lung injury in mice by suppressing inflammatory responses and apoptosis, which is mediated via inhibition of the NF-κB and HIF-1α pathways.

Prognostic significance of immunohistochemical expression profiles of some antigens in cervical cancer

Aim. To evaluate the prognostic significance of immunohistochemical expression profile of some antigens in patients with cancer of the cervix. Methods. Analysed was the data of primary medical records (medical history and hospital records) and information of the Belarusian Cancer Registry of the 100 women who received special treatment in the Republican Scientific and Practical Centre of Oncology and Medical Radiology named after Alexandrov and in Grodno Regional Clinical Hospital. Histological and immunohistochemical studies of the content of markers Ki-67, Her2/neu, Bcl-2 and p53 in tumors (archival paraffin blocks) were performed. Results. Low level of expression of Ki-67 was detected in 44, moderate - in 19, high - in 37 of patients. Low levels of expression of the mutant p53 protein was detected in 44, moderate - 16, high - 29 of women. Low level of expression of Bcl-2 antigen was found in 92, moderate - in 6, high - in 2 patients. The absence of relationship between the level of the protein HER2/neu and stage cervical cancer was showen. The most prognostic significance had the proliferative activity (the proportion of Ki-67-positive cells), since an increase of this index by 1 unit decreased overall survival observed in 0.9884 times. Multivariate analysis of the cumulative impact of the studied oncogenes on overall survival observed in view of the degree of spread of the tumor process has allowed to develop a formula for calculating the risk of disease progression in a specific clinical observations. Conclusion. The expression of markers Ki-67, p53, Bcl-2, in conjunction with the degree of tumor spread are prognostic criteria of cervical cancer.

Exercise mitigates diclofenac‐induced liver mitochondrial dysfunction

Several strategies have been developed to counteract liver injury as a consequence of nonsteroid anti-inflammatory drugs toxicity. Here, we aimed to determine whether physical exercise results in liver mitochondrial protection against in vitro diclofenac toxicity. Male adult Sprague-Dawley rats were divided into sedentary, 12-week endurance training (ET) and voluntary activity (VPA). In vitro liver mitochondrial function as assessed by oxygen consumption, transmembrane electric potential (ΔΨ) and susceptibility to the mitochondrial permeability transition pore (MPTP) was evaluated in the absence and presence of diclofenac. Mitochondrial oxidative stress markers [MnSOD, aconitase, -SH and MDA, SIRT3, p66shc(Ser36)/p66shc ratio] and apoptotic signalling (caspases 3, 8 and 9, Bax, Bcl-2 and CypD) were assessed. Content of OXPHOS components and qualitative liver morphological evaluation were assessed. Despite no effects of ET and VPA on basal liver mitochondrial oxygen consumption or ΔΨ endpoints, exercised animals showed lower susceptibility to MPTP. Diclofenac-induced decrease in ΔΨ, increased state 4 respiration and susceptibility to MPTP opening were all prevented by exercise. Under untreated conditions, VPA group showed higher aconitase activity, while ET decreased MDA and increased Bax content. VPA decreased p66shc(Ser36), complex III and V OXPHOS subunits. Both ET and VPA increased complex IV OXPHOS subunit, and SIRT3 and Bcl-2 content and decreased caspase 9 activity. Unexpectedly, ET and VPA decreased ANT. Both chronic physical exercise models augmented the resistance to in vitro diclofenac-induced mitochondrial alterations, including increased MPTP susceptibility, possibly by modulating oxidative stress and MPTP regulators.

Protection of ginsenoside Rg1 on chondrocyte from IL-1β-induced mitochondria-activated apoptosis through PI3K/Akt signaling

Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Ginsenoside Rg1 protects cells by antagonizing apoptosis. This study aimed to investigate the protective effect of Rg1 on interleukin 1β (IL-1β)-induced chondrocyte apoptosis and the underlying molecular mechanisms. Chondrocytes were harvested from the joints of 1-week-old Sprague-Dawley rats. After treated with 10μg/mL Rg1 for 2h, the chondrocytes were cultured with 10ng/mL IL-1β to induce cytotoxicity. Cell viability was assessed with MTT assays. Annexin V/propidium iodide staining and terminal deoxynucleotidyl transferase dUTP nick-end labeling were used to detect chondrocyte apoptosis. The contents of total Akt, phosphorylated Akt (p-Akt), Bcl-2, Bax, and cytochrome C (Cyt c) were determined by Western blotting assay. A quantitative colorimetric assay was used to determine caspase-3 activity. Our present findings have shown that pre-treatment of chondrocytes with Rg1 reduces IL-1β induced cytotoxicity/apoptosis. Rg1 pretreatment also decreases the activity of IL-1β that reduces expression of Bcl-2 and level of p-Akt, and increases Bax activity, Cyt c release, and caspase-3 activation. It also reverses the activity of IL-1β that reduces the expression of tissue inhibitor of metalloproteinase-1 expression and increased the synthesis of matrix metalloproteinase-13, with the net effect of inhibiting extracellular matrix degradation. These results indicate that Rg1 may protect chondrocytes from IL-1β-induced apoptosis via the phosphatidylinositol 3-kinase/protein kinase B signaling pathway, through preventing caspase-3 release.

The Association between Splenocyte Apoptosis and Alterations of Bax, Bcl-2 and Caspase-3 mRNA Expression, and Oxidative Stress Induced by Dietary Nickel Chloride in Broilers

Two hundred and forty avian broilers were equally divided into four groups, and raised with a corn-soybean basal diet or the same diet supplemented with 300, 600, 900 mg/kg NiCl2 for 42 days. Numbers or percentages of apoptotic splenocytes by flow cytometry (FCM) and TUNEL were higher (p < 0.05 or p < 0.01) in the 300, 600 and 900 mg/kg groups than those in the control group. Results measured by qRT-PCR and ELISA showed that mRNA expression and contents were significantly higher (p < 0.05 or p < 0.01) in Bax and Caspase-3, and were significantly lower (p < 0.05 or p < 0.01) in Bcl-2 of the 300, 600 and 900 mg/kg groups. Also, the SOD, CAT and GSH-Px activities, and the ability to inhibit hydroxyl radical, and GSH contents were significantly decreased (p < 0.05 or p < 0.01), and MDA contents were increased (p < 0.05 or p < 0.01) in all groups. In conclusion, dietary NiCl2 in excess of 300 mg/kg caused apoptosis, altered Bax, Bcl-2 and Caspase-3 mRNA expression levels and contents, and induced oxidative stress in the spleen. Also, splenocyte apoptosis was closely related to the alternations of Bax, Bcl-2 and Caspase-3 mRNA expression, and oxidative damage. The splenic immunity and blood filtration functions were impaired in broilers.

Dietary nickel chloride induces oxidative stress, apoptosis and alters Bax/Bcl-2 and caspase-3 mRNA expression in the cecal tonsil of broilers

The purpose of this study was to investigate the effects of dietary NiCl2 on antioxidant function, apoptosis, and the protein expression, mRNA expression and contents of the bcl-2, bax and caspase-3 in the cecal tonsil of broilers. 280 one-day-old avian broilers were divided into four groups and fed on a corn–soybean basal diet as control diet or the same basal diet supplemented with 300, 600 and 900mg/kg of NiCl2 for 42days. The activities of SOD, CAT and GSH-Px, and the ability to inhibit hydroxy radical, and GSH content were significantly decreased in all experimental groups. MDA content was significantly increased. The protein expression, mRNA expression and contents of bcl-2 were decreased, and bax and caspase-3 were increased in all experimental groups. The percentages of apoptotic lymphocytes were significantly increased. In conclusion, dietary NiCl2 in excess of 300 mg/kg caused oxidative stress, and then induced decreased the protein expression, mRNA expression and the contents of bcl-2, and increased protein expression, mRNA expression and the contents of bax and caspase-3 proteins in the cecal tonsil. The local intestinal mucosal immunity could finally be impaired due to the oxidative stress and apoptosis in the cecal tonsil caused by NiCl2.

Effects of diazoxide postcongditioning on the cell viability,phospho glycogen synthase kinase-3β,Bcl-2,Bax protein expressionin in cultured adult rat cardiac myocytes suffered from hypoxia/reoxygenation injury

Objective To investigate the effect of diazoxide (DZ) postconditioning mediating the expression of phospho glycogen synthase kinase-3β,Bcl-2,Bax and the cell viability during hypoxia/reoxygenation (H/R) in cultured adult rat cardiac myocytes.Methods The model of isolated adult rat cardiac myocytes was established and randomly divided into 5 groups (n=6):① Normal group:caridocytes were incubated at 37 ℃ in a humidified atmosphere of 5％ carbon dioxide CO2) and 95％ air for 6 h; ② H/R group:cardiocytes were exposed to 3 h of hypoxia followed hy 3 h of reoxygenation; ③ DZ group:cardiocytes were exposed to 3 h of hypoxia followed by 3 hof reoxygenation,while 100 μ mol/L DZ was added in medium 5 min after reoxygenation; ④ DZ+5-hydroxydecanoate(5-HD) group:cardiocytes were exposed to 3 h of hypoxia followed by 3 h of reoxygenation,while 100 μmol/L 5-HD was added in medium rightly after 3 h' hypoxia and 100 μmol/L DZ was added in medium 5 min after reoxygenation; ⑤ 5-HD group:3 h of hypoxia followed by 3 h of reoxygenation,while 100 μmol/L 5-HD was added in medium after 3 h' hypoxia.The cell viability was assayed by the rate of Rod-shaped cells; the expression of pGSK-3β,Bcl-2 and Bax were assessed by western blot 3 h after reoxygenation.Results After 3 h reoxygenation,contraction of the single myocyte is (13.12±0.19)％ in normal group.Compared with the normal group,the cell viability was gready decreased in the other 4 groups [(7.97±0.22)％ for H/R group,(10.48± 0.20)％ for DZ group,(7.97±0.19)％ for the DZ+5-HD group,(8.22±0.22)％ for the 5-HD group](P＜0.05).The cell viability in DZ group was(64±5)％.Compared with the H/R group,it was significantly increased(P＜0.05).The content of Bcl-2 and pGSK-3β in DZ group were higher(P＜0.05),while the expression of Bax was lower(P＜0.05).But these effects were abolished with administration of 5-HD rightly after hypoxia(P＞0.05); There was no statistical difference between H/R group and 5-HD group(P＞0.05).Conclusions DZ could alleviate hypoxia/reoxygenation injury through mediating the expression of pGSK-3β,Bax,Bcl-2 proteins via opening of mitoKATP channel. Key words: Diazoxide; Postconditioning; Mitochondrial ATP-sensitive potassium channel; glycogen synthase kinase-3β; Bcl-2 ; Bax

Neuroprotective effects of madecassoside in early stage of Parkinson's disease induced by MPTP in rats

In this study, we investigated the neuroprotective effects of madecassoside, isolated from the Chinese medicinal herb Centella asiatica, in the rat model of early phase of parkinsonism. During intragastric administrations of madecassoside for 7days, the rats were injected with MPTP on the 7th day. And for the following 14days, madecassoside were also administered. On the 14th day, the behavioral tests were assessed after 1h of administration. And then, the rats were sacrificed, substantia nigra and striatum were dissected. The content of DA, MDA, GSH, and Bcl-2/Bax gene expression levels and BDNF protein level was determined. Treatment with madecassoside was found to improve locomotor dysfunction and to protect dopaminergic neuron by antagonizing MPTP induced neurotoxicity. Madecassoside significantly attenuated the MPTP-induced reduction of dopamine in the striatum. The MDA contents were significantly decreased while the GSH levels, Bcl-2/Bax ratio and protein expression of BDNF were significantly increased in madecassoside treated groups. These results indicated that madecassoside was effective in recovering MPTP-induced early signs of parkinsonism via its neuroprotective effects including reversing the depletion of DA, antioxidant activity, increasing ratio of Bcl-2/Bax, increasing protein expression of BDNF.

247 AT1 RECEPTORS AND CA2+/CALMODULIN-DEPENDENT PROTEIN KINASE II INHIBITION UNLIKE THEIR COMBINATION DURING ISCHEMIA-REPERFUSION IS ASSOCIATED WITH CHANGES IN CONTENT OF OXIDATIVE STRESS AND APOPTOTIC MARKERS AND IMPROVED CONTRACTILE FUNCTION IN HEART

<h3>Introduction</h3> Ca2+/calmodulin-dependent protein kinase II (CaMKII) is a crucial regulator of Ca2+-handling and excitation-contraction coupling in cardiomyocytes. Lately, an oxidative activation of CaMKII has been described. Oxidative stress is an integral component of ischemia/reperfusion (IR) injury which results in a complex of subcellular and molecular changes leading to impaired cardiac function and cell death. As AT1 receptor activation promotes reactive oxygen species production through NADPH oxidase system it may be hypothesized that this signaling cascade might play an important role in oxidative activation of CaMKII under IR conditions. <h3>Methods</h3> To test this, the isolated Langendorff-perfused hearts of Wistar rats treated with losartan (20 mg/kg, p.o., 14 days) as well as control ones were subjected to ischemia (30 min) followed by reperfusion (40 min). A role of CaMKII was studied by using a specific CaMKII inhibitor (KN-93, 0,5 µmol/dm3) which was present in the perfusion solution 10 min before onset of ischemia, during ischemia and first 10 min of reperfusion. During the whole IR protocol, myocardial parameters were being continuously recorded. Protein content of total, oxidized CaMKII, oxidative stress markers, such as pro-oxidant NADPH oxidase (NOX2) and antioxidant superoxide dismutase (MnSOD) and catalase (CAT) as well as apoptotic markers (Bax, Bcl-2, cyt c) was evaluated in left ventricles by Western blotting. <h3>Results</h3> In the IR hearts, inhibition of AT1 receptors or CaMKII alone normalized the protein content of antioxidant proteins MnSOD and CAT to the values of the non-ischemic hearts. Likewise, the protein content of oxidized CaMKII was modified. Interestingly, the protein content of NOX2 was significantly increased in IR-subjected group treated with losartan, suggesting a negative feedback due to a permanent AT1 inhibition. Moreover, the protein content of anti-apoptotic Bcl-2 was not changed upon losartan treatment nor CaMKII inhibition in the ischemic hearts. On the other hand, pro-apoptotic Bax and cytochrome C were upregulated in the non-ischemic losartan group. Simultaneous inhibition of AT1 receptors and CaMKII had no additive effect on content of any protein studied. On the other hand, although AT1 receptor inhibition or CaMKII inhibition improved postischemic recovery of left-ventricular developed pressure (LVDP), the simultaneous inhibition of AT1 receptors and CaMKII abolished this beneficial effect. <h3>Conclusion</h3> In conclusion, it is likely that AT1 receptor signaling cascade plays a role in oxidative activation of CaMKII documented by normalized anti-oxidant protein content and by improved contractile function of heart after AT1 inhibition. However, a simultaneous inhibition of CaMKII and AT1 receptors resulted in worsened LVDP recovery suggesting that excessive inhibition of CaMKII activation and therefore diminished activation of CaMKII target proteins of Ca2+-handling may be deleterious.

Combined Inhibitory Effects of Pyruvate and Low Temperature on Postovulatory Aging of Mouse Oocytes1

This study tested the hypothesis that oocyte aging could be prevented for a longer time by reducing the culture temperature while supplementing the culture medium with more pyruvate. Newly ovulated mouse oocytes were cultured at various temperatures for various times in HCZB medium (Kimura and Yanagimachi, Biol Reprod 1995; 52:709-720) containing various concentrations of pyruvate before examining for aging parameters and developmental potential. The increase in susceptibility to activating stimuli was efficiently prevented when oocytes were cultured in HCZB with 10.27 mM pyruvate at 37°C for 6 h, 25°C for 24 h, 15°C for 96 h, and 5°C for 48 h. Satisfactory blastocyst development of both parthenotes and fertilized zygotes was achieved after oocyte culture in HCZB containing 10.27 mM pyruvate at 37°C for 6 h, 25°C for 24 h, 15°C for 36 h, and 5°C for 24 h. Transfer of two-cell embryos or blastocysts showed no difference between newly ovulated control oocytes and oocytes cultured at 15°C for 36 h in either term pregnancy, live young per pregnant recipient, live young/transferred embryos, or birth weight of young. Oocytes with impaired developmental potential after culture at 15°C for 96 h and at 5°C for 48 h showed unrecoverable decreases in the content of glutathione, the glutathione/oxidized glutathione ratio, the BCL2 content, and in the numbers of oocytes with normal spindles and cortical granule distribution, suggesting induction of oxidative stress, which caused oocyte apoptosis and cytoskeleton alterations by downregulating BCL2. Because oocytes cultured at 15°C for 36 h were activated or fertilized after a 6-h recovery culture, aging of ovulated mouse oocytes has been successfully prevented for 42 h without impairing their developmental potential.

In vitro salicylate does not further impair aging-induced brain mitochondrial dysfunction

Aging and drug-induced side effects may contribute to the deterioration of mitochondrial bioenergetics in the brain. One hypothesis is that the combination of both deleterious stimuli accelerates the process of mitochondrial degradation, leading to progressive bioenergetic disruption. The hypothesis was tested by analyzing the isolated and combined effect of aging and salicylate, a vastly used anti-inflammatory drug, on isolated brain fractions in rats.Male Wistar rats were divided according to age in two groups: adult (n=8, 19 weeks of age) and aged (n=8, 106 weeks of age). In vitro endpoints of brain mitochondrial function including oxygen consumption and transmembrane electric potential (ΔΨ) were evaluated in the absence and in the presence of salicylate (0.5mM). Brain mitochondrial susceptibility to calcium-induced permeability transition pore (MPTP) was also assessed. Mitochondrial oxidative stress was determined by measuring aconitase and manganese-superoxide dismutase (SOD) activity, and content in sulfhydryl groups (SH) and malondialdehyde (MDA). Mitochondrial content in apoptotic-related proteins Bax, Bcl-2 and cyclophilin D was determined by Western Blotting.Under basal, untreated, conditions, aging affected brain mitochondrial state 3 respiration, maximal ΔΨ developed, ADP phosphorylation lag phase and calcium-induced MPTP. Interestingly, MDA decreased and Mn-SOD activity increased in the aged group. Brain mitochondrial Bcl-2 content decreased and Bax/Bcl-2 ratio increased in aged group. Salicylate incubation for 20min increased lipid peroxidation in the aged group only and stimulated respiration during state 2, accompanied by decreased ΔΨ, although both effects were independent of the animal age.We confirmed that both aging and salicylate per se impaired brain mitochondrial bioenergetics, although the combination of both does not seem to worsen the mitochondrial end-points studied.

Therapeutic effect of mesenchymal stem cells in rats with intracerebral hemorrhage: Reduced apoptosis and enhanced neuroprotection

Stem cell transplantation has been used to improve neural function in intracerebral hemorrhage (ICH). However, reports on bone marrow-derived mesenchymal stem cell (MSC) transplantation in ICH are limited. We aimed to explore the therapeutic effect and related mechanisms by transplantation of MSCs in rats with ICH. An experimental rat ICH model was established by intrastriatal administration of collagenase. The rats were randomly divided to receive either rat MSCs or PBS solution intravenously. In addition, behavioral tests using the modified neurological severity score (mNSS) were performed following ICH. Immunohistochemistry was performed to detect the Brdu-labeled MSCs and the protein expression of caspase 2, NF200 and GFAP in neural tissues. Western blotting and ELISA were performed to measure the protein expression of Akt and bcl-2 or the protein content of G-CSF and BDNF. The MSC-transplanted group demonstrated better neural function on the mNSS test following ICH compared with the control group (P<0.05). The MSC-transplanted group also showed reduced hemorrhage volume at 24 and 72 h following ICH. In the perihematomal regions of rat brain with ICH, a substantial number of Brdu-labeled MSCs were observed, and a high protein expression of caspase 3, NF200 and GFAP was found in the MSC-transplanted group. The protein content of Akt, Bcl-2, G-CSF and BDNF were all elevated by MSC transplantation. Intravenously transplanted MSCs are capable of improving functional recovery and restoring neurological deficits in experimental ICH. The mechanisms are associated with enhanced survival and differentiation of neural cells, and increased expression of anti-apoptotic proteins and trophic factors.

Effect of Cyclosporine on Apoptosis in Bronchial Epithelial Cells

ObjectivesAmong airway complications, posttransplantation infections are related to impaired mucociliary clearance, which may represent a toxicity of cyclosporine (CsA), a potent, widely used immunosuppressive drug after organ transplantations. Since several recent studies have demonstrated CsA treatment to directly induce apoptosis in several cell types, we investigated its effects on airway cells using the human bronchial epithelial cell line BEAS-2B. MethodsProliferation was measured by using a Cell Counting Assay Kit by exposing cells to CsA (0, 10, 30, 50, or 100 μg/mL). Apoptotic cells were identified using fluorescence microscopy after 4′, 6-diamidino-2-phenylidole (DAPI) staining. Western blot analysis was performed to evaluate the contents of poly(adenosine diphosphate-ribose) polymerase (PARP), p27, Bcl-2, and caspase-3. ResultsCell viability decreased dependent on the CsA concentration: 100.00 ± 0.01% with 0 μg CsA as control; 98.65 ± 0.02% with 10 μg (P < .05 vs control); 95.41 ± 0.05% with 30 μg (P < .05 vs control); 38.84 ± 0.04% (P < .001 vs control) with 50 μg; and 15.28 ± 0.05% with 100 μg (P < .001 vs control). Apoptotic cells detected with DAPI showed chromatin condensation and nuclear fragmentation. CsA induced p27 and p53, as well as degradation of 116-kd PARP into an 89-kd fragment. ConclusionCsA induced apoptosis in human bronchial epithelial cells.

Participation of apoptotic proteins in hypothalamic regulation of volume of population of the red-backed vole Clethrionomys rutilus

The content of the antiapoptotic protein Bcl-2 and of the proapoptotic enzyme caspase-3 in the paraventricular nucleus (PVN) of sexually immature red-backed voles is studied in the course of the population cycle. The significant change of the Bcl-2 and procaspase-3 in the PVN neurons is established at all cycle phases. The low volume of population (under the most favorable conditions of the existence of the animals) is revealed to be characterized by the moderately increased or high expression of the Bcl-2 protein alongside with low or moderately increased caspase-3 activity. This is suggested to provide the PVN adequate reaction at the low population volume. At high population volume (under conditions of increased stress in the overcrowded population at the phase of peak and especially of fall), a significant decrease of the Bcl-2 expression is established with simultaneous increase of the caspase-3 activity. The disbalance in synthesis of apoptotic proteins seems to lead to disturbances of PVN functions at phases of peak and fall and, as a consequence, to a decrease of adaptive possibilities of these animals, which might be one of important causes of essential elimination of the animals at the autumn-winter period.

Absorption of arginine-vasopressin and arginine-vasotocin in small intestine of the frog Rana temporaria

The content of the antiapoptotic protein Bcl-2 and of the proapoptotic enzyme caspase-3 in the paraventricular nucleus (PVN) of sexually immature red-backed voles is studied in the course of the population cycle. The significant change of the Bcl-2 and procaspase-3 in the PVN neurons is established at all cycle phases. The low volume of population (under the most favorable conditions of the existence of the animals) is revealed to be characterized by the moderately increased or high expression of the Bcl-2 protein alongside with low or moderately increased caspase-3 activity. This is suggested to provide the PVN adequate reaction at the low population volume. At high population volume (under conditions of increased stress in the overcrowded population at the phase of peak and especially of fall), a significant decrease of the Bcl-2 expression is established with simultaneous increase of the caspase-3 activity. The disbalance in synthesis of apoptotic proteins seems to lead to disturbances of PVN functions at phases of peak and fall and, as a consequence, to a decrease of adaptive possibilities of these animals, which might be one of important causes of essential elimination of the animals at the autumn-winter period.

Effects of smoking and tumor process on the contents of key proteins of apoptosis and activity of antioxidant enzymes in blood

The effects of smoking on the contents of the apoptosis markers Bcl-2 and p53 proteins in blood plasma; the activity of the antioxidant (AO) enzymes Cu, Zn-superoxide dismutase (SOD), glutathione peroxidase (GP), glutathione reductase (GR), glutathione S-transferase (GST), and catalase; and the content of malondialdehyde (MDA) in erythrocytes from healthy donors and cancer patients were studied. Two groups of donors were revealed among healthy smokers: one with high SOD and GP activities and high Bcl-2 protein levels and the other with lower Bcl-2 levels compared with those found in nonsmokers. In the group of cancer patients (both smokers and nonsmokers), significantly increased p53 protein levels and increased activity of GST were found. A negative correlation between MDA and GST in the group of smoking healthy donors and a positive correlation between MDA and p53 in cancer patients were found. The results suggest a relationship between the components of enzymatic defence and lipid peroxidation and the content of apoptosis regulator proteins in healthy smokers and cancer patients.

Anti-apoptosis effects of Captopril, Milkvetch root and their combination on HUVEC induced by H2O2

ObjectiveTo investigate the protective effects and mechanisms of ACEI (Captopril), Milkvetch root and their combination on human umbilical vascular endothelial cells (HUVECs) following the damage of hydrogen peroxide (H2O2).MethodsHUVEC were...

Cheating death at the dawn of life: Developmental control of apoptotic repression in the preimplantation embryo

During early development, the mammalian embryo is resistant to pro-apoptotic signals because of biochemical properties of the mitochondrion and nucleus. Mitochondria of the bovine two-cell embryo are resistant to depolarization because of low amounts of the proapoptotic protein BAX and high concentrations of the anti-apoptotic protein BCL2. As development proceeds, BAX content increases, BCL2 content declines, and mitochondria becomes capable of pore formation and depolarization in response to pro-apoptotic signals. The nucleus of the two-cell embryo is resistant to degradation by the DNase DFFB because epigenetic modifications, including DNA methylation and histone deacetylation, mask internucleosomal sites for DNA cleavage. Blastomere DNA becomes progressively less methylated during development so that DNA becomes accessible to cleavage by DFFB.

Neurotoxic Effect of the Complex of the Ovine Prion Protein (OvPrPC) and RNA on the Cultured Rat Cortical Neurons

Prion diseases are conformational diseases, many factors are involved in altering the conformation of prion, such as RNA, DNA, pH, and copper etc. However the neurotoxic mechanism of prion diseases is not clear yet. The aim of this study is to investigate the effect of the nucleoprotein complex of RNA and recombinant ovine prion protein (OvPrP(C)) on the cultured rat cortical neurons in vitro. Our previous study revealed that the nucleoprotein complex (OvPrP(C)-RNA) is characterized with high β sheet conformation and proteinase K resistance. Here we found that the OvPrP(C)-RNA induced marked neuronal cell death by the MTT (3-(4,5-dimethyl-thiazole -2-yl)-2,5-diphenyl -tetrazolium bromide) and TUNEL (TdT mediated biotin-dUTP nicked-end labeling) assay, and the neurotoxic effects were confirmed by testing the content of Bcl-2 Associated X protein (Bax) in the immunoprecipitation assay and Western blot assay. Compared to the control group, there is no significant difference of active Bax or total Bax after RNA alone treatment or OvPrP(C) alone treatment, but the OvPrP(C)-RNA induced significant increases of active Bax level, while the contents of total Bax had no obvious changes after OvPrP(C)-RNA treatment. The results suggested that OvPrP(C)-RNA is neurotoxic in vitro, which added further evidence to the current understanding of mechanism of cellular injury by RNA molecules for transformation of the PrP(C) to PrP(Sc).