Mito-targeted antioxidant prevents cardiovascular remodelling in spontaneously hypertensive rat by modulation of energy metabolism.

Hypertension induced left ventricular hypertrophy (LVH) augments the risk of cardiovascular anomalies. Mitochondrial alterations result in oxidative stress, accompanied by decrease in fatty acid oxidation, leading to the activation of the hypertrophic program. Targeted antioxidants are expected to reduce mitochondrial reactive oxygen species more effectively than general antioxidants.

Column-Free Method for Isolation and Culture of C-Kit Positive Stem Cells from Atrial Explants.

Ever since the discovery of stem cells, their isolation from tissues and expansion in culture has been extensively studied due to its potential for therapeutic application. The magnetic-assisted cell sorting (MACS) method is the most widely used technique for the sorting of cells based on their cell surface markers. Though effective, the major drawbacks are high cost and the requirement for the frequent replacement of the columns.

Protective effect of antioxidant Tempol on cardiac stem cells in chronic pressure overload hypertrophy.

Aims: Cardiac hypertrophy, an independent risk factor for cardiac failure; is associated with oxidative stress. Decline in the proportion of healthy cardiac stem cells (CSCs), possibly mediated by oxidative stress can lead to cardiac failure. The present study was carried out to examine the hypothesis that reduction of oxidative stress restores CSC efficiency and prevents progressive cardiac remodelling.

Association of histamine with hypertension-induced cardiac remodeling and reduction of hypertrophy with the histamine-2-receptor antagonist famotidine compared with the beta-blocker metoprolol.

The association of histamine with adverse cardiac remodeling in chronic pressure overload has not received much attention. A pilot study in spontaneously hypertensive rats (SHRs) indicated a reduction of left ventricular hypertrophy (LVH) with a histamine-2-receptor (H2R) antagonist (famotidine). This finding prompted a detailed investigation of temporal variation in myocardial histamine and H2R expression and the cardiovascular response to H2R antagonism compared with that of the conventional beta-blocker metoprolol.

Modulation of cardiac stem cell characteristics by metoprolol in hypertensive heart disease.

Cardiac stem cells (CSCs) play a vital role in cardiac remodeling. Uncontrolled hypertension leads to cardiac hypertrophy, followed by cardiac failure. Pathological remodeling is associated with enhanced oxidative stress.

Accelerated decline in cardiac stem cell efficiency in Spontaneously hypertensive rat compared to normotensive Wistar rat.

Cardiac hypertrophy is recognized as an independent risk factor for cardiac failure. Efficient management of hypertensive heart disease requires identification of factors that can possibly mediate the transition from hypertrophy to failure. Resident cardiac stem cells have a prominent role in the maintenance of cardiac tissue homeostasis.

Sub-physiological oxygen levels optimal for growth and survival of human atrial cardiac stem cells.

Cardiac stem cells reside in niches where the oxygen levels are close to 3%. For cytotherapy, cells are conventionally expanded in ambient oxygen (21% O) which represents hyperoxia compared to the oxygen tension of niches. Cardiosphere-derived cells (CDCs) are then transplanted to host tissue with lower-O levels.

Differential response of human cardiac stem cells and bone marrow mesenchymal stem cells to hypoxia-reoxygenation injury.

Cardiosphere-derived cells (CDCs) and bone marrow mesenchymal stem cells (MSCs) are popularly used in stem cell therapy for myocardial regeneration. The cell type that survives and maintains stem cell characteristics in the adverse microenvironment following ischemia-reperfusion injury is presumed to be ideal for transplantation. The study was therefore aimed at identifying the cell type with relatively greater resistance to ischemia-reperfusion injury.

Testosterone reduces vascular relaxation by altering cyclic adenosine monophosphate pathway and potassium channel activation in male Sprague Dawley rats fed a high-salt diet.

Objectives: Male gender and high-salt diet are risk factors for hypertension. The effect of chronic exposure to testosterone is an increase in vascular tone but its influence upon responses induced by other vasoactive agents is not clear. We considered the possibility of interactions between testosterone and a high-salt diet in the mechanisms that are involved in the regulation of vascular tone.

Relaxation response of abdominal aorta to androgens in orchidectomised Sprague-Dawley rats fed a high-salt diet.

Previous studies have demonstrated the acute relaxant effects of androgens on normal arterial beds, but not on any with underlying or induced pathologies. This study investigated whether the status of the gonads affects the direct actions of androgens on isolated abdominal aorta from male Sprague-Dawley rats fed a high-salt diet. A high-salt diet reduced the relaxation response to exogenous testosterone, but not to dehydroepiandrosterone (DHEA).

Cardoguard, an Ayurvedic antihypertensive formulation, prevents cardiac remodeling in spontaneously hypertensive rats by inhibition of ERK and PKCε signaling pathways.

Ayurveda is an Indian system of medicine. Despite clinical efficacy, lack of scientific validation has limited the effective use of Ayurvedic drugs. Cardoguard is an Ayurvedic antihypertensive drug formulated by Nagarjuna Herbal Concentrates Ltd.

Testosterone relaxes abdominal aorta in male Sprague-Dawley rats by opening potassium (K(+)) channel and blockade of calcium (Ca(2+)) channel.

Aim: To investigate the direct effect of testosterone and its precursor/derivative dehydroepiandrosterone (DHEA) on isolated rat abdominal aortic rings.

Materials And Methods: 3mm abdominal aortic rings that were obtained from 3 months old male Sprague-Dawley rats were suspended in organ baths containing Hepes buffered PSS bubbled with 100% oxygen. Relaxation response to testosterone and DHEA was studied in noradrenalin pre-contracted rings.

Multiple signaling pathways coordinately mediate reactive oxygen species dependent cardiomyocyte hypertrophy.

The heart responds to an increased demand arising due to physiological stimuli or pathological insults by hypertrophy of myocytes. Reactive oxygen species (ROS) have recently been identified as the molecular intermediates in the translation of mechanical stimuli to cellular response. Different signal transduction pathways have been implicated with cardiac hypertrophy, prominent among them being, mitogen-activated protein kinase (MAPK), protein kinase C (PKC) and calcineurin.

Isolation of ckit-positive cardiosphere-forming cells from human atrial biopsy.

There is increasing interest in developing cell-based therapies to regenerate functional muscle and blood vessels in infarcted dysfunctional myocardium, using stem cells resident in the adult heart. The objective of our study was to identify an easy and cost-effective method for the isolation and expansion of human adult cardiac-resident stem cells. The cells were isolated from right atrial biopsy samples obtained from patients with ischemic heart disease, who were undergoing coronary artery bypass grafting.

Endocardial endothelial cells stimulate proliferation and collagen synthesis of cardiac fibroblasts.

Given that vascular endothelial cells play an important role in the modulation of vascular structure and function, we hypothesized that endocardial endothelial cells (EECs) may have a modulator role in regulating the cardiac interstitial cells. Endocardial endothelial cells were isolated from freshly collected pig hearts and cardiac fibroblasts were isolated from 3- to 4-d-old Wistar rats. Fibroblasts were cultured in the presence or absence of conditioned medium from EECs.

Variation in mitogenic response of cardiac and pulmonary fibroblasts to cerium.

Fibroproliferative response of rat heart and lung fibroblasts to the lanthanide cerium was examined, as the element has been implicated in the causation of cardiac and pulmonary fibrosis. Fibroblasts from both of the organs were morphologically identical, and the response to fetal bovine serum, a nonspecific mitogen, was also comparable. The oxygen radical generator (hypoxanthine + xanthine oxidase [Hyp.