Publications by authors named "Beis I"

Juvenile systemic lupus erythematosus (jSLE) is a chronic multisystem inflammatory disease that manifests before the age of 16 years, following a remitting - relapsing course. The clinical presentation in children is multifaceted, most commonly including constitutional, hematological, cutaneous, renal, and neuropsychiatric symptoms. Neuropsychiatric manifestations range widely, affecting approximately 14-95 % of jSLE patients.

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Excessive levels of reactive oxygen species (ROS) result in numerous pathologies including muscle disorders. In essence, skeletal muscle performance of daily activities can be severely affected by the redox imbalances occurring after muscular injuries, surgery, atrophy due to immobilization, dystrophy or eccentric muscle contraction. Therefore, research on the potential beneficial impact of antioxidants is of outmost importance.

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Curcumin derived from the rhizome of turmeric (Curcuma longa L.), is a well known coloring culinary agent, that has therapeutic properties against diverse pathologies such as cancer, atherosclerosis and heart failure. Given the salutary potential of curcumin, deciphering its mode of action particularly in cardiac cells, is of outstanding value.

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"Calcium paradox" as a term describes the deleterious effects conferred to a heart perfused with a calcium-free solution followed by repletion, including loss of mechanical activity and sarcomere disruption. Given that the signaling mechanisms triggered by calcium paradox remain elusive, in the present study, we tried to investigate them in the isolated perfused heart from Rana ridibunda. Calcium paradox was found to markedly activate members of the MAPKs (p43-ERK, JNKs, p38-MAPK).

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Amphibians are known to better tolerate and endure adverse environmental conditions such as redox imbalances conferred by reactive oxygen species (ROS), compared to mammals. Interestingly, the exact adaptation strategies and signaling mechanisms mediating these effects have not been fully elucidated. Therefore, in the present study, we probed into the molecular response of the isolated perfused Rana ridibunda heart to curcumin, in the context of mitogen-activated protein kinases (MAPKs) phosphorylation patterns and apoptotic markers occurrence.

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Article Synopsis
  • Gender appears to affect the cardioprotective benefits of ischemic preconditioning (PreC) and postconditioning (PostC), particularly in female animals after ovariectomy (Ov).
  • A study on female rabbits showed that PostC significantly reduced infarct size only in the ovariectomized group, suggesting a restoration of protection through specific cellular pathways.
  • Findings indicated lower levels of estradiol and nitric oxide in ovariectomized rabbits, with an increase in Akt phosphorylation when PostC was applied, hinting at the involvement of the RISK pathway in cardioprotection post-Ov.
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Impaired insulin sensitivity (insulin resistance) is a common denominator in many metabolic disorders, exerting pleiotropic effects on skeletal muscle, liver, and adipose tissue function. Heme oxygenase-1 (HOX-1), the rate-limiting enzyme in heme catabolism, has recently been shown to confer an antidiabetic effect while regulating cellular redox-buffering capacity. Therefore, in the present study, we probed into the mechanisms underlying the effect of insulin on HOX-1 in C2 skeletal myoblasts.

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The exact physiological role of oxidative stress as a primary cause for skeletal muscle pathological conditions involving muscle degeneration remains elusive. Therefore, the present study was performed so as to decipher the signalling pathways orchestrating the potential cytoprotective role of heme oxygenase 1 (HOX-1) as well as cyclooxygenase 2 (COX-2) in skeletal myoblasts exposed to H(2)O(2). Cell treatment with H(2)O(2) (0.

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In the present study we investigated the signal transduction cascades triggered by acute thermal stress in Mytilus galloprovincialis gills. This particular species has been reported to exhibit a significant tolerance to high temperatures; thus, it was intriguing to examine the molecular mechanisms responsible for this extraordinary trait. In particular, exposure to 30 degrees C was found to cause a significant and sustained stimulation of p38-MAPK phosphorylation while the activation profile of JNKs was transient and relatively moderate.

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One of the most significant insults that jeopardize cardiomyocyte homeostasis is a surge of reactive oxygen species (ROS) in the failing myocardium. Early growth response factor-1 (Egr-1) has been found to act as a transcriptional regulator in multiple biological processes known to exert deleterious effects on cardiomyocytes. We thus investigated the signaling pathways involved in its regulation by H2O2.

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Background: Performing axillary artery cannulation, during cardiopulmonary bypass in patients with an atherosclerotic ascending aorta or acute dissection of the ascending aorta and arch, is of growing interest. Our aim is to present our experience, to describe the surgical technique, and to demonstrate the sufficient cerebral and total body perfusion through axillary artery cannulation.

Patients And Methods: Twenty-two patients (17 male, five female) underwent surgical treatment with the axillary technique.

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pH is one of the most important physiological parameters, with its changes affecting the function of vital organs like the heart. However, the effects of alkalosis on the regulation of cardiac myocyte function have not been extensively investigated. Therefore, we decided to study whether the mitogen-activated protein kinase (MAPK) signaling pathways [c-Jun NH2-terminal kinases (JNKs), extracellular signal-regulated kinases (ERKs), and p38 MAPK] are activated by alkalosis induced with Tris-Tyrode buffer at two pH values, 8.

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In the present study the activation of p38 mitogen-activated protein kinase (p38-MAPK) and c-Jun N-terminal kinases (JNKs) by hyperthermia was investigated in the isolated perfused Rana ridibunda heart. Hyperthermia (42 degrees C) was found to profoundly stimulate p38-MAPK phosphorylation within 0.5 h, with maximal values being attained at 1 h [4.

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We investigated the response of alphaB-crystallin to oxidative stress and calpain inhibition in an attempt to elucidate the signalling pathways mediating its phosphorylation. Given the high expression levels of alphaB-crystallin in cardiac muscle one can evaluate the significance of its participation in preservation of homeostasis under adverse conditions. H9c2 cardiac myoblasts were used as our experimental model since their response reflects the signal transduction pathways activated by stress conditions in the myocardium.

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The aim of this study was to investigate the activation of JNK1/2 signalling pathway and the respective cellular phenotype of H9c2 cardiac myoblasts during two distinct types of oxidative insult. We examined the dose- and time-dependent activation of JNK1/2 pathway by exogenous H2O2, both under transient and sustained stimulation. At 2 h of either sustained or transient treatment, maximal phosphorylation of c-Jun was observed, coincidently with the activation of nuclear JNK1/2; under sustained stress, these phosphorylation levels remained elevated above basal for up to 6 h, whereas under transient stress they declined to basal ones within 4 h of withdrawal.

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Nicorandil, a selective mitochondrial K(ATP) channel opener, reinstates the waned protection after multiple cycles of preconditioning. In this study, we determined the signal transduction activated in heart after 3 or 8 cycles of preconditioning and prolonged ischemia in rabbits treated with placebo or nicorandil. In a first series (eight groups) we evaluated the (%) infarct to risk ratio after 30 min ischemia/3 h reperfusion and in a second series (six groups), we assessed the intracellular levels of cyclic GMP (c-GMP), protein kinase C (PKC) activity and p38-mitogen activated protein kinase (p38-MAPK) phosphorylation from heart samples taken during the long ischemia.

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Mitogen-activated protein kinases (MAPKs) constitute one of the most important intracellular signalling pathways. In particular, the p38-MAPK subfamily is known to be activated under various stressful conditions, such as mechanical or oxidative stress. Furthermore, cobalt chloride (CoCl2) has been shown to mimic hypoxic responses in various cell lines and cause overproduction of reactive oxygen species (ROS).

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In the present study, we investigated the induction of the p38-MAPK signalling pathway by copper, as exemplified by CuCl(2), in the isolated perfused heart of the amphibian Rana ridibunda. We found that p38-MAPK phosphorylation by CuCl(2) occurs in a dose-dependent manner, with maximum activation (8.73+/-1.

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Vitamin E (VitE) is considered an antioxidant agent. One or more brief periods of ischemia (isc), followed by short reperfusion (rep), increase the tolerance of the heart to a subsequent prolonged ischemia, a phenomenon known as ischemic preconditioning (PC). Mitochondrial KATP channels (mitoKATP), cyclic-GMP (cGMP), and free radicals are involved in the mechanism of PC, whereas some antioxidants abolish this benefit.

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Skeletal muscle is highly adapted to respond to oxidative imbalances, since it is continuously subjected to an increased production of reactive oxygen species (ROS) during exercise. Oxidative stress, however, has been associated with skeletal muscle atrophy and damage in many diseases. In this study, we examined whether MAPK and NF-kappaB pathways participate in the response of skeletal myoblasts to oxidative stress, and whether there is a cross talk between these pathways.

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We investigated the effects of different antioxidants such as L-ascorbic acid, catalase, and superoxide dismutase (SOD), on the p38-MAPK activation induced by oxidative stress in the isolated perfused amphibian heart. Oxidative stress was exemplified by perfusing hearts with 30 microM H(2)O(2) for 5 min or with the enzymatic system of xanthine/xanthine oxidase (200 microM/10 mU/ml, respectively) for 10 min. H(2)O(2)-induced activation of p38-MAPK (7.

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Previous studies have shown that the cardioprotective effect of ischemic preconditioning (IPC) can be mimicked pharmacologically with clinically relevant agents, including nitric oxide (NO) donors. However, whether pharmacological preconditioning shares the same molecular mechanism with IPC is not fully elucidated. The present study aimed to determine the activation of mitogen-activated protein kinases (MAPKs) (ERK1/2, p38 MAPK and p46/p54 JNKs) during ischemia and at reperfusion in nitroglycerin-induced preconditioning as compared to IPC and to correlate this with the conferred cardioprotection in anesthetized rabbits.

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We investigated the activation of the p38-MAPK signalling pathway during extracellular pH changes in the isolated perfused amphibian heart. Extracellular alkalosis (pH 8.5 or 9.

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One of the most important challenges that cardiomyocytes experience is an increase in the levels of reactive oxygen species (ROS), i.e., during ischemia, reperfusion as well as in the failing myocardium.

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