Psidium guajava leaves extract alters colonic microbiome composition and reduces intestinal sodium absorption in rats exposed to a high-sodium diet.

Objectives: High sodium intake is a major risk factor for hypertension and renal diseases. Previous studies have shown that a suspension of ethanolic extract of Psidium guajava (guava) leaves (PsE) has antihypertensive effects in rats on a high-sodium diet (HSD), but some mechanisms to that remain unexplored. This study explored whether oral PsE treatment affects sodium handling by the intestine and alters the gut microbiome in HSD-fed rats.

Antihypertensive effect of a nanoemulsion of leaves extract in sodium-dependent hypertensive rats.

(DC) is an important botanical source of Brazilian green propolis and have many compounds with potential antihypertensive activity. However, little is known about the specific antihypertensive properties of DC, or the mechanisms involved. Here we aimed to chemically characterise an ethanolic DC extract (eDC), test its antihypertensive properties and the involvement of neurogenic mechanisms using an animal model of salt-dependent hypertension.

Green Propolis: A Review of Pharmaceutical Patents with Potential Therapeutic Applications.

Green propolis is a resin produced from Baccharis dracunculifolia, which has as its main compounds flavonoids, derivatives of cinnamic acids, such as artepillin C and baccarin. This resin has antibacterial, antifungal, anti-inflammatory, antioxidant, and anticancer activities. This review aimed to analyze pharmaceutical patents containing green propolis in various formulations.

Reducing sugar intake through chronic swimming training: Exploring palatability changes and central vasopressin mechanisms.

Excessive sugar intake has been associated with the onset of several non-communicable chronic diseases seen in humans. Physical activity could affect sweet taste perception which may affect sugar intake. Therefore, it was investigated the chronic effects of swimming training on sucrose intake/preference, reactivity to sucrose taste, self-care in neurobehavioral stress, and the possible involvement of the vasopressin type V receptor in sucrose solution intake.

Effects of Psidium guajava L. leaves extract on blood pressure control and IL-10 production in salt-dependent hypertensive rats.

Psidium guajava (guava) leaves extract displays anti-hypertensive properties by mechanisms not yet fully understood. Here, we investigated whether sympathetic drive and immune signaling mechanisms are involved with the antihypertensive effect of the guava extract in a model of salt-dependent hypertension. Raw guava extract (rPsE) was characterized by colorimetric and UPLC-MS techniques.

The gut-brain axis and sodium appetite: Can inflammation-related signaling influence the control of sodium intake?

Sodium is the main cation present in the extracellular fluid. Sodium and water content in the body are responsible for volume and osmotic homeostasis through mechanisms involving sodium and water excretion and intake. When body sodium content decreases below the homeostatic threshold, a condition termed sodium deficiency, highly motivated sodium seeking, and intake occurs.

Swimming training improves cardiovascular autonomic dysfunctions and prevents renal damage in rats fed a high-sodium diet from weaning.

New Findings: What is the central question of this study? How does swimming exercise training impact hydro-electrolytic balance, renal function, sympathetic contribution to resting blood pressure and cerebrospinal fluid (CSF) [Na ] in rats fed a high-sodium diet from weaning? What is the main finding and its importance? An exercise-dependent reduction in blood pressure was associated with decreased CSF [Na ], sympathetically driven vasomotor tonus and renal fibrosis indicating that the anti-hypertensive effects of swimming training in rats fed a high-sodium diet might involve neurogenic mechanisms regulated by sodium levels in the CSF rather than changes in blood volume.

Abstract: High sodium intake is an important factor associated with hypertension. High-sodium intake with exercise training can modify homeostatic hydro-electrolytic balance, but the effects of this association are mostly unknown.

Salt-dependent hypertension and inflammation: targeting the gut-brain axis and the immune system with Brazilian green propolis.

Systemic arterial hypertension (SAH) is a major health problem around the world and its development has been associated with exceeding salt consumption by the modern society. The mechanisms by which salt consumption increase blood pressure (BP) involve several homeostatic systems but many details have not yet been fully elucidated. Evidences accumulated over the last 60 decades raised the involvement of the immune system in the hypertension development and opened a range of possibilities for new therapeutic targets.

Fitness is improved by adjustments in muscle intracellular signaling in rats with renovascular hypertension 2K1C undergoing voluntary physical exercise.

Aim: To evaluate physical fitness and cardiovascular effects in rats with renovascular hypertension, two kidneys, one clip (2K1C) submitted to voluntary exercise (ExV).

Main Methods: 24 h after surgery (SHAM and 2K1C) rats were submitted to ExV for one week (adaptation). ExV adherent rats were separated into exercise (2K1C-EX and SHAM-EX) or sedentary (2K1C-SED and SHAM-SED) groups.

Acute volume expansion decreased baroreflex response after swimming but not after running exercise training in hypertensive rats.

Physical training (ET) is important to restore the reflex sensitivity involved in controlling blood pressure in various diseases. Recent investigations have demonstrated an interaction between cardiopulmonary baroreceptors and arterial baroreflex during dynamic exercise. Considering that acute and chronic hemodynamic responses to swimming (SW) are different from the race (RUN), the objective of this study was to evaluate the effect of SW and RUN on baroreflex response before and after acute volume expansion in spontaneously hypertensive rats (SHR).

Changes in cardiovascular responses to chemoreflex activation of rats recovered from protein restriction are not related to AT receptors.

What is the central question of this study? In this study, we sought to investigate whether cardiovascular responses to peripheral chemoreflex activation of rats recovered from protein restriction are related to activation of AT receptors. What is the main finding and its importance? This study highlights the fact that angiotensinergic mechanisms activated by AT receptors do not support increased responses to peripheral chemoreflex activation by KCN in rats recovered from protein restriction. Also, we found that protein restriction led to increased resting ventilation in adult rats, even after recovery.

Bezold-Jarisch reflex in sino-aortic denervated malnourished rats.

In this study we assessed the role of Bezold-Jarisch reflex (BJR) in the regulation of blood pressure (BP) of malnourished (MN) and control rats (CN) with sino-aortic denervation (SAD). Fischer rats were fed diets containing either 6% (MN) or 15% (CN) protein for 35 days after weaning. These rats underwent sham or SAD and catheterization of femoral artery and vein for BP measurements and drug injection.

Central antioxidant therapy inhibits parasympathetic baroreflex control in conscious rats.

Baroreceptor reflex is an important system for neural control of blood pressure. Recently, reactive oxygen species (ROS) have been shown to play an important role in neuronal activity of central areas related to blood pressure control. The aim of this study was to investigate the effects elicited by ascorbic acid (AAC) and N-acetylcysteine (NAC) injections into the 4thV on the parasympathetic component of the baroreflex.

Sympathoinhibition to Bezold-Jarisch reflex is attenuated in protein malnourished rats.

Malnutrition affects cardiovascular reflexes, including chemoreflex and baroreflex. In this study we assessed the hypothesis that malnourishment changes the responses in mean arterial pressure (MAP), heart rate (HR) and renal sympathetic nerve activity (RSNA) evoked from Bezold-Jarisch reflex (BJR). Fischer rats were fed diets containing either (6% malnourished or 14% control) protein for 35 days after weaning.

Cardiovascular responses to hydrogen peroxide into the nucleus tractus solitarius.

The nucleus tractus solitarius (NTS), a major hindbrain area involved in cardiovascular regulation, receives primary afferent fibers from peripheral baroreceptors and chemoreceptors. Hydrogen peroxide (H(2)O(2)) is a relatively stable and diffusible reactive oxygen species (ROS), which acting centrally, may affect neural mechanisms. In the present study, we investigated effects of H(2)O(2) alone or combined with the glutamatergic antagonist kynurenate into the NTS on mean arterial pressure (MAP) and heart rate (HR).

Cardiopulmonary reflex is attenuated in iron overload conscious rats.

Increased iron intake can lead to iron accumulation in serum and tissues. Its has been described that serum and tissue iron overload increase reactive oxygen species (ROS) levels and reduce the effectiveness of the cardiovascular neural mechanisms involved in the maintenance of the arterial blood pressure whithin a narrow range of variation, therefore, iron overload may disrupt cardiovascular homeostasis contributing to physiopathological status development. In the present study we evaluated whether iron accumulated in serum or tissue of awake animals affect the cardiovascular homeostasis through changes in the cardiopulmonary reflex (CPR).

Malnutrition enhances cardiovascular responses to chemoreflex activation in awake rats.

Several studies in the literature suggest that low-protein intake is associated with increases in sympathetic efferent activity and cardiovascular disease. Among the possible mechanisms, changes in the neurotransmission of cardiovascular reflexes have been implicated. Therefore, the present study comprised the evaluation of chemoreflex responsiveness in rats subjected to a low-protein diet during the 35 days after weaning.

Cardiovascular responses produced by central injection of hydrogen peroxide in conscious rats.

Reactive oxygen species (ROS) have been shown to modulate neuronal synaptic transmission and may play a role on the autonomic control of the cardiovascular system. In this study we investigated the effects produced by hydrogen peroxide (H(2)O(2)) injected alone or combined with the anti-oxidant agent N-acetil-l-cysteine (NAC) or catalase into the fourth brain ventricle (4th V) on mean arterial pressure and heart rate of conscious rats. Moreover the involvement of the autonomic nervous system on the cardiovascular responses to H(2)O(2) into the 4th V was also investigated.