Aldosterone is a hormone secreted by the kidneys. Its effects are far more complicated than it was previously thought. Beyond regulating sodium and volume homeostasis by its epithelial action, aldosterone hormone exhibits its effects in other organs, such as the heart, blood vessels and central nervous system. Some of these actions are not related to the aldosterone -induced stimulation of classical mineralocorticoid receptors.
High aldosterone secretion induces oxidative stress, endothelial dysfunction, inflammation and fibrosis in the vasculature, heart and kidney.
High Aldosterone Levels -
Aldosteronism prevalence, cause for high blood pressure
Primary aldosteronism is common in patients with hypertension. In patients with mild to moderate hypertension the prevalence of primary aldosteronism is 5% to 10%, whereas in subjects with resistant hypertension the prevalence is approximately 20%. As such, primary aldosteronism has become the most common secondary cause of hypertension.
Diagnosis of hyperaldosteronism is recommended in hypokalemic (low potassium level) hypertension, in therapy-resistant hypertension (at least three drugs and blood pressue still greater than 140/90 mmHg), and in incidentally discovered adrenal gland tumors. For screening, the ratio between plasma aldosterone and plasma renin concentration should be measured.
The benefits of aldosterone receptor antagonists (spironolactone and eplerenone) for patients with heart failure were shown in 2 recent randomized controlled trials. Some of the proposed mechanisms of action of aldosterone antagonists are (1) inhibition of myocardial and vascular remodeling, (2) blood pressure reduction, (3) decreased collagen deposition, (4) decreased myocardial stiffness, (5) prevention of hypokalemia and arrhythmia, (6) modulation of nitric oxide synthesis, and (7) immunomodulation. Like many hormone receptors, the aldosterone receptor can be either nuclear or membrane bound. Most of the activities of the aldosterone receptor are subserved by the nuclear receptors and often lead to alterations in gene transcription. Although these agents are well tolerated in carefully selected patient populations that meet the inclusion criteria of large clinical trials, their use in unselected elderly patients with heart failure and multiple comorbidities has been associated with a significant risk of hyperkalemia and renal failure.
Adding an aldosterone antagonist to a standard therapy for type 2 diabetes may decrease albuminuria without contributing to hyperkalemia.
Aldosterone and Heart
Renal dysfunction is a constant feature of congestive heart failure and is a stronger predictor of mortality than left ventricular ejection fraction or New York Heart Association classification. In heart failure, a reduction of glomerular filtration rate and renal plasma flow occurs, although the filtration fraction increases. There are many reason for this pattern. A reduction in effective circulating volume stimulates sympathetic activity and the renin-angiotensin-aldosterone system, and it is associated with increased concentrations of atrial natriuretic peptide, brain natriuretic peptide, and tumor necrosis factor alpha.
ADH Aldosterone Angiotensin
- the Renin Angiotensin Aldosterone System
The renin angiotensin aldosterone system has a very important role to play in managing blood volume, arterial pressure, and cardiovascular function. The most critical site for renin release is the kidney. Sympathetic stimulation, renal artery hypotension, and decreased sodium delivery to the distal tubules stimulate the release of renin by the kidney. Renin is an enzyme that acts upon a circulating substrate, angiotensinogen, that undergoes cleavage to from angiotensin I. Vascular endothelium, particularly in the lungs, has an enzyme, angiotensin converting enzyme (ACE), that cleaves off two amino acids to form angiotensin II.
Am J Hypertens. 2014 Dec 26. Aldosterone Levels, Aortic Stiffness, and Wave Reflection in Essential Hypertensive The aim of the present study was to evaluate the grade of arterial stiffening, in relation to aldosterone (ALDO) and plasma renin activity (PRA) levels, in essential never-treated hypertensive patients. Arterial stiffness indices are higher among essential hypertensive patients with high normal serum and urine ALDO levels, pointing to a causal relationship between renin-angiotensin-aldosterone system activation and large artery properties.
Indian J Pharmacol. 2015. Effects of aqueous extract of Hibiscus sabdariffa on the renin-angiotensin-aldosterone system of Nigerians with mild to moderate essential hypertension: A comparative study with lisinopril. The present study investigated the effects of aqueous extract of Hibiscus sabdariffa (HS) on the three basic components of renin-angiotensin-aldosterone system: Plasma renin, serum angiotensin-converting enzyme (ACE), and plasma aldosterone (PA) in mild to moderate essential hypertensive Nigerians and compared with that of lisinopril, an ACE inhibitor. HS reduced serum ACE and PA in mild to moderate hypertensive Nigerians with equal efficacy as lisinopril. These actions are possibly due to the presence of anthocyanins in the extract.
Q. Does CoQ10 help with hypertension?
A. I'm not sure. The evidence I have seen thus far has been mixed. A low coq10 dose of 30 to 50 mg a few times a week is an option.
DHEA supplement use or
interfere with aldosterone levels?
Good question. I don't know.