Michael Bader

Cardiac hypertrophy is regulated by a complex interplay of pro- and anti-hypertrophic factors. Here, we report a novel anti-hypertrophic pathway composed of catalase, protein kinase CK2 (CK2), and apoptosis repressor with caspase recruitment domain (ARC). Our results showed that ARC phosphorylation levels, CK2 activity, and catalase expression levels were decreased in the hearts of the angiotensinogen transgenic mice and in cardiomyocytes treated with the hypertrophic stimuli, including ...

The aim of this study was to evaluate the angiotensin (Ang)-(1-7) effects in isolated mouse hearts. The hearts of male C57BL/6J and knockout mice for the Ang-(1-7) receptor Mas were perfused by the Langendorff method. After a basal period, the hearts were perfused for 20 minutes with Krebs-Ringer solution (KRS) alone (control) or KRS containing Ang-(1-7) (0.22 pmol/L), the Mas antagonist A-779 (115 nmol/L), the angiotensin type 1 receptor antagonist losartan (2.2 micromol/L), or the ...

OBJECTIVE: We assessed the role of glycogen synthase kinase-3beta (GSK-3beta) and kinin B2 receptor in mediating tissue kallikrein's protective effects against cardiac hypertrophy.

METHODS: We investigated the effect and mechanisms of tissue kallikrein using hypertrophic animal models of rats as well as mice deficient in kinin B1 or B2 receptor after aortic constriction (AC).

RESULTS: Intramyocardial delivery of adenovirus containing the human tissue kallikrein gene resulted in ...

OBJECTIVE: The first aim of the present study was to assess plasma and kidney angiotensin II (ANG II) levels and renal cortical ANG II receptor subtype 1A (AT1A) mRNA expression in hypertensive Ren-2 transgenic rats (TGR) and in normotensive Hannover Sprague-Dawley (HanSD) rats. The second aim was to investigate potential differences between TGR and HanSD in blood pressure (BP) and renal functional responses to either intravenous (i.v.), i.e. systemic, or intrarenal (i.r.) AT1 receptor ...

The recently cloned (pro)renin receptor [(P)RR] mediates renin-stimulated cellular effects by activating mitogen-activated protein kinases and promotes nonproteolytic prorenin activation. In vivo, (P)RR is said to be blocked with a peptide consisting of 10 amino acids from the prorenin prosegment called the "handle-region" peptide (HRP). We tested whether human prorenin and renin induce extracellular signal-regulated kinase (ERK) 1/2 activation and whether the direct renin inhibitor ...

Although liver fatty acid-binding protein (L-FABP) is an important binding site for various hydrophobic ligands in hepatocytes, its in vivo significance is not understood. We have therefore created L-FABP null mice and report here their initial analysis, focusing on the impact of this mutation on hepatic fatty acid binding capacity, lipid composition, and expression of other lipid-binding proteins. Gel-filtered cytosol from L-FABP null liver lacked the main fatty acid binding peak in the ...

BACKGROUND: Endoscopic ultrasonography (EUS) and somatostatin receptor scintigraphy (SRS) can detect a high percentage of gastroenteropancreatic neuroendocrine tumours especially in the upper gastrointestinal tract. The ability of these procedures to localise primary tumour lesions and metastases of gastrinomas and insulinomas was evaluated in comparison with transabdominal ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI).

PATIENTS AND METHODS: In a ...

BACKGROUND: Kinins are important mediators of inflammation and act through stimulation of two receptor subtypes, B1 and B2. Leukocyte infiltration contributes to the pathogenesis of autoimmune inflammation in the central nervous system (CNS), occurring not only in multiple sclerosis (MS) but also in experimental autoimmune encephalomyelitis (EAE). We have previously shown that the chemokines CCL2 and CCL5 play an important role in the adhesion of leukocytes to the brain microcirculation ...

Kinins, a special class of polypeptides, are represented by bradykinin (BK), kallidin (Lys-BK), as well as their metabolites. The biological actions of these polypeptides binding on their receptors (B1 and B2) have been related to inflammation process, cytokines action, glutamate release and prostaglandins production. Usually, kinin B1 receptor is not expressed at a significant level under physiologic conditions in most tissues, but its expression is induced by injury, or upon exposure ...

Cryopreservation as a process can be divided into two methods: conventional freezing and vitrification. The high effectiveness of vitrification in comparison with conventional freezing for human oocytes and embryos is shown, whereas data on human ovarian tissue are limited. The aim of this study was to compare the safety and effectiveness of conventional freezing and vitrification of human ovarian tissue. Ovarian tissue fragments from 15 patients were transported to the laboratory within ...

RATIONALE: Vascular wall stretch is the major stimulus for the myogenic response of small arteries to pressure. The molecular mechanisms are elusive, but recent findings suggest that G protein-coupled receptors can elicit a stretch response.

OBJECTIVE: To determine whether angiotensin II type 1 receptors (AT1R) in vascular smooth muscle cells exert mechanosensitivity and identify the downstream ion channel mediators of myogenic vasoconstriction.

METHODS AND RESULTS: We used mice ...

BACKGROUND: Ischemic postconditioning (PostC) is a recently described cardioprotective modality against reperfusion injury, through series of brief reflow interruptions applied at the very onset of reperfusion. It is proposed that PostC can activate a complex cellular signaling cascade, in which cell membrane receptors could serve as the upstream triggers of PostC. However, the exact subtypes of such receptors remain controversial or uninvestigated. To this context, the purpose of ...

Bradykinin (BK) is produced and acts at the site of injury and inflammation. In the CNS, migration of microglia toward the lesion site plays an important role pathologically. In the present study, we investigated the effect of BK on microglial migration. Increased motility of cultured microglia was mimicked by B1 receptor agonists and markedly inhibited by a B1 antagonist but not by a B2 receptor antagonist. BK induced chemotaxis in microglia isolated from wild-type and B2-knock-out mice ...

BACKGROUND AND PURPOSE: Brain edema is detrimental in ischemic stroke and its treatment options are limited. Kinins are proinflammatory peptides that are released during tissue injury. The effects of kinins are mediated by 2 different receptors (B1 and B2 receptor [B1R and B2R]) and comprise induction of edema formation and release of proinflammatory mediators.

METHODS: Focal cerebral ischemia was induced in B1R knockout, B2R knockout, and wild-type mice by transient middle cerebral ...

Compelling evidence indicates that the endothelium-derived potent vasoconstrictor endothelin-1 (ET-1) stimulates aldosterone secretion by interacting with specific receptors. Although two different ET-1 receptors have been identified and cloned, the receptor subtype involved in mediating aldosterone secretion is still unknown. Accordingly, we wished to investigate whether the genes of ET-1 and of its receptors A and B are expressed in the normal human adrenal cortex. We designed specific ...