Key takeaways:
~ Aldosterone synthase, encoded by the CYP11B2 gene, is essential for regulating blood pressure by controlling aldosterone production, which balances sodium and potassium levels in the kidneys.
~ Genetic variants in the CYP11B2 gene increase the risk of hypertension, stroke, atrial fibrillation, and other cardiovascular conditions.
What is aldosterone synthase?
The CYP11B2 gene encodes aldosterone synthase, an enzyme involved in aldosterone biosynthesis.
First, what is aldosterone? Aldosterone is a steroid hormone that regulates blood pressure and plasma sodium and potassium levels. It works on the kidneys to balance out electrolytes (Na+ and K+) as a way of influencing blood pressure and blood volume.
In the body, think of ‘water follows sodium’. We all know a meal high in salt can leave us feeling ‘puffy’, and the action here is of the same concept. Aldosterone influences the kidneys to retain sodium while also excreting potassium. This shift in the electrolyte balance that allows for sodium retention directly increases water retention…by water following sodium. This action allows for an increase in blood volume and pressure.[ref]
Aldosterone synthase is produced in the adrenal cortex and regulated by the RAAS pathway (renin-angiotensin-aldosterone system). As the limiting factor in aldosterone production, the aldosterone synthase enzyme is crucial for blood pressure regulation and electrolyte balance.
The aldosterone synthase enzyme catalyzes a reaction involving deoxycorticosterone in a multistep process to form aldosterone. Deoxycorticosterone is a steroid hormone produced by the adrenal glands, and it can also regulate potassium, similar to aldosterone. The key, though, is that deoxycorticosterone doesn’t usually decrease sodium levels much compared to potassium.
The precursor for deoxycorticosterone (and thus, aldosterone) is progesterone. The hormone progesterone is synthesized in the body from cholesterol.
What does high aldosterone cause?
High aldosterone is linked to:[ref][ref]
- high blood pressure
- stroke
- headaches, fatigue (related to low potassium known as ‘hypokalemia’)
- osteoporosis
Related Article: Osteoporosis Genes and Prevention Strategies
What does very low aldosterone cause?
Very low aldosterone levels are a serious problem. Lack of aldosterone, often found in Cushing’s disease, is linked to salt-wasting, growth retardation in children, and failure to thrive. Altered potassium levels and low blood pressure can also occur.[ref][ref]
CYP11B2 Genotype Report
Lifehacks:
Medications for high blood pressure:
People with hypertension along with the G/G genotype for rs1799998, may respond well to certain blood pressure-reducing drugs ending in -sartans. The -sartan drugs are angiotensin II receptor blockers.[ref][ref] These agents block the action of angiotensin II thus causing vasodilation and increased sodium and water excretion. (Talk with your doctor, of course!)
Aldosterone synthase inhibitors are a new class of hypertensive drugs under development. Inhibiting CYP11B2 decreases aldosterone and subsequently increases deoxycorticosterone, thus changing the sodium-potassium balance.[ref]
Researchers are also looking at ways to reduce aldosterone by stopping the stimulation of aldosterone in the adrenals. Substance P binds to a receptor to increase aldosterone synthase and blocking that receptor with drugs (in clinical trials) reduces aldosterone.[ref] If Substance P sounds familiar, it is a neuropeptide released in pain, vomiting, and hot flashes. In the adrenal glands, substance P partly influences aldosterone stimulation.
Natural ways to reduce high blood pressure with CYP11B2:
Related Articles and Topics:
References:
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