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Aluminum accumulation, glutathione (GSH) and malondialdehyde (MDA) concentrations as well as catalase (CAT) and superoxide dismutase (SOD) activities were determined in erythrocytes and brain and liver homogenates of BALB/c mice treated with Al3+ (7.5 mg/kg/day (0.15 LD50) as AlCl3 (37.08 mg/kg/day), whereas HCl (30.41 mg/kg/day) was used as Cl− control, the treatments were performed for 21 days, i.p., in the presence and absence of rosmarinic acid (0.2805 mg/kg/day (0.05 LD50), 21 days, i.g.) or carvacrol (0.0405 mg/kg/day (0.05 LD50), 21 days, i.g.). The treatment with AlCl3 increased GSH concentration in erythrocytes only slightly and had no effect on brain and liver homogenates. Rosmarinic acid and carvacrol strongly increased GSH concentration in erythrocytes but decreased it in brain and liver homogenates. However, AlCl3 treatment led to Al accumulation in mice blood, brain, and liver and induced oxidative stress, assessed based on MDA concentration in the brain and liver. Both rosmarinic acid and carvacrol were able to counteract the negative Al effect by decreasing its accumulation and protecting tissues from lipid peroxidation. AlCl3 treatment increased CAT activity in mice brain and liver homogenates, whereas the administration of either rosmarinic acid or carvacrol alone or in combination with AlCl3 had no significant effect on CAT activity. SOD activity remained unchanged after all the treatments in our study. We propose that natural herbal phenolic compounds rosmarinic acid and carvacrol could be used to protect brain and liver against aluminum induced oxidative stress leading to lipid peroxidation.

Exposure to cadmium (Cd) is known to alter immune responses.Acanthopanax senticosus(Rupr. et Maxim.) Harms (AS) extract, an antioxidant-containing complex of phenolic compounds, tetracyclic triterpenoids/steroids, and polysaccharides, is known to produce Cd mobilization and excretionin vivo. Building upon earlier findings, the aim of the study was to evaluate the effects of an AS extract on Cd accumulation and changes in the presence of splenic immune cells in hosts during a chronic metal exposure. Chronic Cd exposure of BALB/cmice was induced by providing them solutions containing different levels of CdCl2(25 or 250 mg/L) in double-distilled water, with/without a concurrent presence of AS root extract (approximately 151 g material/L), for 8 wk. At the study end, Cd levels in spleen were measured. Levels of key splenic immune cells, including macrophages, T-lymphocytes, and B-lymphocytes, were determined by immunohistochemistry using, respectively, CD68, CD3, and CD20 antibodies. The results indicated that chronic consumption of AS extract in the presence of the high dose of CdCl2led to a significant decrease in Cd levels in mouse spleen. The effects of AS on the lower CdCl2dose were less apparent. In addition, the presence of AS and Cd increased the amount of macrophages and both B and T lymphocytes in mouse spleen relative to concentrations that were lowered as a result of chronic metal only intake. [ABSTRACT FROM PUBLISHER]

Objective: To evaluate the effect of aluminum ions (Al3+) on the total protein synthesis and on the activities of tRNALeu and leucyl-tRNA synthetase from mouse liver in vivo. Methods: Experiments were done on white laboratory mice using i.p. injections of 0.5 LD50 AlCl3 solution (25 mg Al3+/kg body weight). The intensity of protein synthesis or tRNALeu acceptor activity was evaluated by incorporation of [14C]-leucine into newly synthesized peptides and proteins. The leucyl-tRNA synthetase activity was measured by the initial rate of tRNALeu aminoacylation. Results: We determined the effect of Al3+ on the intensity of total protein synthesis and on the activities of translation apparatus components in mouse liver in vivo. The most evident aluminum-induced changes of protein synthesis in mouse liver occurred within the first 8 – 16 h after intoxication. The intensity of protein synthesis increased by 47% 16 h after treatment with Al3+. Later, protein synthesis went down; 16 h after injection of AlCl3 solution the activity of leucyl-tRNA synthetase increased by 20%. However, the acceptor activity of tRNALeu decreased by 23%. We supposed that the increase in leucyl-tRNA synthetase activity is a part of compensatory response to the diminished activity of tRNALeu. Conclusions: The most evident Al-induced alterations of the protein synthesis in mouse liver in vivo occur within the first 8 – 16 h after intoxication. An increase in the leucyl-tRNA synthetase activity is a part of compensatory response to the diminished activity of tRNALeu. [ABSTRACT FROM AUTHOR]

Flavonol (-)-epicatechin and its derived dimer procyanidin B2, present in high amounts in cocoa products, have been shown to exert beneficial effects on the heart and cardiovascular system; however, their mechanism of action has not been fully elucidated. We studied effects of (-)-epicatechin and procyanidin B2 on the oxidative phosphorylation of isolated rat heart mitochondria. (-)-Epicatechin and procyanidin B2 had stimulating effect (up to 30% compared to control) on substrate-driven (State 2) mitochondrial respiration. Their effect was dependent on the respiratory substrates used. (-)-Epicatechin at higher concentrations (from 0.27 µg/mL) significantly decreased (up to 15%) substrate- and ADP-driven (State 3) mitochondrial respiration in case of pyruvate and malate oxidation only. Procyanidin B2 (0.7-17.9 ng/mL) inhibited State 3 respiration rate up to 19%, the most profound effect being expressed with succinate as the substrate. (-)-Epicatechin at concentrations of 0.23 µg/mL and 0.46 µg/mL prevented loss of the cytochrome c from mitochondria when substrate was succinate, supporting the evidence of membrane stabilizing properties of this flavonol. Thus, both (-)-epicatechin and procyanidin B2 directly influenced mitochondrial functions and the observed effects could help to explain cardiometabolic risk reduction ascribed to the consumption of modest amounts of cocoa products.

Though heart failure can mainly be caused by systolic or diastolic dysfunction, the impairments of the neurohormonal, immune, and hemostatic systems are observed too. Therefore, it is not easy to determine etiology of the syndrome. Parameters that can be helpful to predict chronic heart failure, to evaluate its course and the risk of complications are still being searched. The aim of this article is to review the recent studies in order to find the links between the coagulation system and the development of chronic heart failure. Stress is a key factor for the development of most diseases including chronic heart failure too. Signals of emotional and physical stress via particular structures trigger an increase in concentrations of the following hormones: noradrenaline, renin, angiotensin II, aldosterone, vasopressin. It is proved that it causes the disorders of the coagulation system: an increase in the following factors of plasma coagulation (fibrinogen, VII, VIII, fibrinopeptide A, thrombin-antithrombin complex), fibrinolysis (D-dimer), endothelium (interleukin 1, endothelin 1, vascular cell adhesion molecules, endothelial growth factor), platelet activity (von Willebrand factor, intercellular adhesion molecules, platelet factor 4, P-selectin, thromboxane A(2), thromboglobulin, CD63P) and cytokines (tumor necrosis factor, interleukin 6) and decrease in E-selectin. The role of particular coagulation factors for the development of chronic heart failure has not been understood yet. Thus, it is necessary to carry out further studies.

Objective: The aim of this study was to investigate effect of anoxia and Polyscias filicifolia Bailey biomass tincture on the activities of different tRNA and aminoacyl-tRNA synthetases in isolated pig heart., Material and Methods: The isolated pig heart was perfused according to the modified method of Langendorf, using an artificial blood circulation apparatus. Anoxia 20 min in duration was performed by perfusion of isolated heart with Krebs-Henseleit bicarbonate buffer saturated with gas mixture (95% N(2) and 5% CO(2)). Control heart was perfused with the same buffer saturated with gas mixture (95% O(2) and 5% CO(2)). Effect of Polyscias filicifolia Bailey biomass tincture was evaluated by perfusion of isolated heart with a buffer containing tincture. Total tRNA and aminoacyl-tRNA synthetases were isolated from pig heart. Activities of tRNA and aminoacyl-tRNA synthetases were measured by the aminoacylation reaction using C(14)-amino acids., Results: Anoxia 20 min in duration has caused a decrease in the acceptor activity of tRNA and increase in the activities of aminacyl-tRNA synthetases. Polyscias filicifolia Bailey tincture did not affect the acceptor activity of tRNA and activities aminacyl-tRNA synthetases. After 20-min anoxic perfusion with the buffer containing Polyscias filicifolia Bailey biomass tincture, the acceptor activities of tRNA increased to the control value and activities of aminacyl-tRNA synthetases reached the control value., Conclusions: The acceptor activity of tRNA from isolated pig heart decreased and activities of aminacyl-tRNA synthetases increased under anoxia. Perfusion with buffer containing tincture of Polyscias filicifolia Bailey biomass restored acceptor activities of tRNA and activities of aminacyl-tRNA synthetases.

Objective: The aim of this study was to evaluate in vivo the effects of cadmium and zinc ions on translational machinery and death of mouse liver cells., Material and Methods: Outbred mice received intraperitoneal injections of cadmium chloride solution (1.4 micromoles cadmium per 1 kg of body weight) and/or zinc sulfate solution (4.8 micromoles zinc per kg of body weight) three times per week for six weeks. Analogical volume of saline solution was injected to the control mice. Protein synthesis was evaluated by incorporation of [(14)C]-labeled leucine into peptides and proteins. Total tRNAs were isolated using deproteinized extract of liver tissue. Postmitochondrial supernatant was as a source of leucyl-tRNA synthetase. Activities of tRNA(Leu) and leucyl-tRNA synthetase were measured by an aminoacylation reaction using [(14)C]-labeled leucine. Liver cell apoptosis was detected by TUNEL assay using in situ cell death detection kit., Results: A decrease in incorporation of [(14)C]-labeled leucine into proteins was detected in liver, kidney, and heart as well as diminution of tRNA(Leu) acceptor activity in cadmium-exposed liver. Cadmium caused activation of the leucyl-tRNA synthetase and induced liver cell apoptosis. Pretreatment of mice with zinc sulfate solution favored to protection of protein synthesis and acceptor activity of tRNA(Leu) against cadmium-induced inhibition. Under co-exposure of mouse liver to cadmium and zinc, activity of the leucyl-tRNA synthetase was at the level of control. Zinc did not influence TUNEL-positive cell number in cadmium-exposed mouse liver., Conclusions: Under subacute intoxication of mice by cadmium, zinc ions protect the translation machinery against inhibition, but do not decrease the number of apoptotic cells in the liver.

Objective: The aim of this study was to investigate effect of Polyscias filicifolia Bailey biomass on protein synthesis process in normoxic and anoxic pig heart., Material and Methods: Experiments were done on isolated pig hearts weighing 100-150 g. Effects of anoxia were evaluated after 20 and 90 min of anoxic perfusion. Control hearts were perfused under aerobic conditions. Investigating action of Polyscias filicifolia Bailey, pig heart was perfused under normoxic and anoxic condition with buffer, which contains tincture Polyscias filicifolia Bailey. For the determination of protein synthesis rate (time of incubation was 15 min) and level (time of incubation was 60 min), incorporation of [14C]-leucine into translational products in a cell-free system was measured., Results: Protein synthesis rate and level in cell-free system decreased by 30% and 20% respectively after 20 min anoxic perfusion and by 48% and 45% respectively after 90 min anoxic perfusion in comparison to the control. Polyscias filicifolia Bailey tincture did not affect the protein synthesis rate and level in cell-free translation system from control pig heart. Polyscias filicifolia Bailey tincture has protective effect on protein synthesis system from pig hearts after 20 min and 90 min anoxic perfusion. Protein synthesis rate and level after 20 min anoxic perfusion with Polyscias filicifolia Bailey tincture was the same as at a control level. However, after 90 min anoxic perfusion with Polyscias filicifolia Bailey tincture protein synthesis rate and level did not reach control level and represented 81% and 76% respectively of control values. Spectrum of newly synthesized polypeptides in cell-free protein synthesis system under anoxic conditions and after treatment with Polyscias filicifolia Bailey tincture did not differ., Conclusions: Protein synthesis rate and level decreased under long and short-term anoxia. Polyscias filicifolia Bailey biomass restore protein synthesis system under anoxia. Neither anoxia, nor Polyscias filicifolia Bailey tincture did not influence spectrum of newly synthesized proteins.

Unlabelled: The objective of this study was to examine effect of lead ions on activities of mice liver tRNA(Leu) and leucyl-tRNA synthetase., Material and Methods: For researching white non-breed laboratory mice (20-25 g) were used. Intoxication with ions of lead was performed by injection of sublethal dose of lead acetate solution (50 mg ions of lead per 1 kg of body weight) into abdominal cavity of laboratory animals. Eight hours after intoxication from intoxicated and normal (control) mice liver preparations of tRNA and aminoacyl-tRNA synthetases were isolated. Acceptor activity of tRNA(Leu) and activity of leucyl-tRNA synthetase were determined in tRNA aminoacylation reaction using [(14)C]-labeled leucine. Actions of lead ions on acceptor activity of tRNA(Leu) and on activity of leucyl-tRNA synthetase from liver of control animals in vitro were determined after addition into reaction mixture different concentrations of lead acetate solution., Results: It was determined that acceptor activity of mice liver tRNA(Leu) 8 h after intoxication with lead ions was reduced by 37 percent and activity of leucyl-tRNA synthetase was increased by 22 percent as compared to control. Experiments in vitro have shown that 10 micro M concentration of lead ions in reaction mixture stimulate acceptor activity of mice liver tRNA(Leu) by 17 percent, higher concentrations of lead ions (30-60 microM)--suppress it by 9-80 percent. The study of leucyl-tRNA synthetase activity in vitro has shown that 30 microM concentration of lead ions in reaction mixture increases activity of this enzyme by 16 percent, higher concentrations of lead ions (40-60 microM)--decrease by 17-23 percent., Conclusions: After 8 h intoxication with lead ions acceptor activity of tRNA(Leu) was decreased and activity of leucyl-tRNA synthetase was increased. It may be part of the compensatory mechanism of the cell to keep synthesis of proteins at the normal level under extreme conditions. Low concentrations of lead ions in reaction mixture increase tRNA(Leu) and leucyl-tRNA synthetase activities, higher concentrations of these ions decrease activity of those components of protein synthesis system. The results show that ions of lead directly suppress activity of both components of translation machinery.