Cardiomyocyte crosstalk with endothelium modulates cardiac structure, function, and ischemia-reperfusion injury susceptibility through erythropoietin.

Erythropoietin (EPO) exerts non-canonical roles beyond erythropoiesis that are developmentally, structurally, and physiologically relevant for the heart as a paracrine factor. The role for paracrine EPO signalling and cellular crosstalk in the adult is uncertain. Here, we provided novel evidence showing cardiomyocyte restricted loss of function in in adult mice induced hyper-compensatory increases in expression by adjacent cardiac endothelial cells via HIF-2α independent mechanisms.

Novel roles of cardiac-derived erythropoietin in cardiac development and function.

The role of erythropoietin (EPO) has extended beyond hematopoiesis to include cytoprotection, inotropy, and neurogenesis. Extra-renal EPO has been reported for multiple tissue/cell types, but the physiological relevance remains unknown. Although the EPO receptor is expressed by multiple cardiac cell types and human recombinant EPO increases contractility and confers cytoprotection against injury, whether the heart produces physiologically meaningful amounts of EPO in vivo is unclear.

Landiolol for the prevention of postoperative atrial fibrillation after cardiac surgery: a systematic review and meta-analysis.

Purpose: Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery. Although the evidence suggests that beta blockers prevent POAF, they often cause hypotension. Landiolol, an ultra-short-acting β blocker, may prevent POAF, without adverse hemodynamic consequences.

Disruption of Physiological Rhythms Persist Following Cessation of Cigarette Smoke Exposure in Mice.

Background: Physiological rhythms in mammals are essential for maintaining health, whereas disruptions may cause or exacerbate disease pathogenesis. As such, our objective was to characterize how cigarette smoke exposure affects physiological rhythms of otherwise healthy mice using telemetry and cosinor analysis.

Methods: Female BALB/c mice were implanted with telemetry devices to measure body temperature, heart rate, systolic blood pressure (SBP), and activity.

Applications of a novel radiotelemetry method for the measurement of intrathoracic pressures and physiological rhythms in freely behaving mice.

Techniques to comprehensively evaluate pulmonary function carry a variety of limitations, including the ability to continuously record intrathoracic pressures (ITP), acutely and chronically, in a natural state of freely behaving animals. Measurement of ITP can be used to derive other respiratory parameters, which provide insight to lung health. Our aim was to develop a surgical approach for the placement of a telemetry pressure sensor to measure ITP, providing the ability to chronically measure peak pressure, breath frequency, and timing of the respiratory cycle to facilitate circadian analyses related to breathing patterns.

Moderate and severe hypoxia elicit divergent effects on cardiovascular function and physiological rhythms.

Key Points: In the present study, we provide evidence for divergent physiological responses to moderate compared to severe hypoxia, addressing an important knowledge gap related to severity, duration and after-effects of hypoxia encountered in cardiopulmonary situations. The physiological responses to moderate and severe hypoxia were not proportional, linear or concurrent with the time-of-day. Hypoxia elicited severity-dependent physiological responses that either persisted or fluctuated throughout normoxic recovery.

Respiratory muscle weakness in the Zucker diabetic fatty rat.

The obesity epidemic is considered one of the most serious public health problems of the modern world. Physical therapy is the most accessible form of treatment; however, compliance is a major obstacle due to exercise intolerance and dyspnea. Respiratory muscle atrophy is a cause of dyspnea, yet little is known of obesity-induced respiratory muscle dysfunction.

Heme oxygenase-1 overexpression exacerbates heart failure with aging and pressure overload but is protective against isoproterenol-induced cardiomyopathy in mice.

Introduction: Heme oxygenase-1 (HO-1) is a cytoprotective enzyme induced by stress. Heart failure is a condition of chronic stress-induced remodeling and is often accompanied by comorbidities such as age and hypertension. HO-1 is known to be protective in the setting of acute myocardial infarction.