Navigation Links
Common genetic mutation increases sodium retention, blood pressure

AUGUSTA, Ga. Nearly 40 percent of the small adrenal tumors that cause big problems with high blood pressure share a genetic mutation that causes patients to retain too much sodium, researchers report.

The study of 47 human, benign adrenal gland tumors also showed a mutation of the gene KCNJ5 is twice as likely to occur in women 71 versus 29 percent as it points to potential new treatments for some patients who don't respond to current hypertension regimens, said Dr. William E. Rainey, Scientific Director of the Adrenal Center at Georgia Health Sciences University.

Addititionally, when scientists put the mutated gene into an adrenal cell, it immediately starts producing the sodium-retaining hormone aldosterone. "We found it turned on a whole series of genes that cause the cell to produce aldosterone," Rainey said.

Typically, KCNJ5 appears to help normalize levels of the sodium-retaining hormone aldosterone by regulating how much potassium is pumped in and out of aldosterone-producing cells on the outer layer of the adrenal glands. Abnormal protein produced by the mutated gene alters the cells' electrical status.

"When this gene has a mutation, the cells lose control and just start producing aldosterone all the time," said Rainey, corresponding author of the study in the Journal of Clinical Endocrinology and Metabolism.

"The combination of too much salt and too much of this hormone leads to high blood pressure and tissue damage," said Rainey. He notes that the vast majority of the 311 million Americans consume too much salt, even if they never pick up a salt shaker, because of high content in breads, processed and fast foods and the like. An estimated 33 percent of Americans are hypertensive and an estimated 1 in 10 have adrenal problems as the cause.

A 2011 study led by Yale University and published in the journal Science showed that the tumors had a KCNJ5 mutation. GHSU researchers, along with colleagues at University of Michigan Medical School, Ann Arbor; University of Torino and University of Padova, Italy; University of Texas Southwestern Medical Center, Dallas; and Keio University,Tokyo linked the gene to aldosterone production.

Now the GHSU Adrenal Center is moving forward with studies to determine why women with adrenal tumors have more of the mutated gene Rainey suspects it's estrogen-related. They also want to know if any of the dozen potassium channel inhibitors already on the market for heart and other disorders can help these patients as well.

Rainey said the gene mutation is one that occurs after birth when most mutations occur and the cause is unknown. About half the people who produce too much aldosterone have tumors, which tend to affect only one of the 2-by-1-inch glands that sit like hats on top of the two kidneys and surgical removal typically fixes their problem. Unexplained enlargement of both glands likely also has a genetic basis and may be medically managed, Rainey said.

One of the many goals of the GHSU Adrenal Center, one of a handful of multidisciplinary centers in the nation, is to better define genes which can result in whole families being impacted. To date, only three genes are known to contribute to the familial form. Aldosterone excess, by whatever means, also is suspected when people under age 40 become hypertensive for no other obvious reason.

The adrenals are extremly efficient glands, producing three additional hormone groups that help maintain homeostasis including cortisol needed for glucose/carbohydrate metabolism, weak sex steroids that likely are the major source of androgens, or male hormones, in women; and the fight or flight hormones epinephrine and norepinephrine. In the event both glands are removed, the vital hormones must be supplemented, Rainey said.

Patients typically come to the GHSU Adrenal Center with unexplained hypertension that isn't responding to traditional therapy. "They are typically on three or four medications and their blood pressure is still not under control," said Dr. Michael A. Edwards, Clinical Director of the Adrenal Center and Chief of the MCG Section of Minimally Invasive and Digestive Diseases Surgery. Computerized tomography done for other reasons can detect over-sized glands or tumors that may be the culprit.


Contact: Toni Baker
Georgia Health Sciences University

Related biology news :

1. Study provides insight on a common heart rhythm disorder
2. Researchers identify Achilles heel of common childhood tumor
3. First comprehensive genomic study of common cold reveals new treatment targets
4. GUMC researchers hone in on new strategy to treat common infection
5. Hairspray is linked to common genital birth defect, says study
6. Common food additive found to increase risk and speed spread of lung cancer
7. Mayo Clinic: Brain disorder suggests common mechanism may underlie many neurodegenerative diseases
8. Scientists uncover evolutionary keys to common birth disorders
9. Common soil mineral degrades the nearly indestructible prion
10. Genetic testing not cost-effective in guiding initial dosing of common blood thinner
11. New vaccine developed for preventing uncommon cold virus
Post Your Comments:
Related Image:
Common genetic mutation increases sodium retention, blood pressure
(Date:11/17/2015)... Nov. 17, 2015 Pressure BioSciences, Inc. (OTCQB: ... development and sale of broadly enabling, pressure cycling technology ... industry, today announced it has received gross proceeds of ... Private Placement (the "Offering"), increasing the total amount raised ... more additional closings are expected in the near future. ...
(Date:11/11/2015)... Minn. , Nov. 11, 2015   MedNet Solutions ... entire spectrum of clinical research, is pleased to announce that ... in Clinical Trials (PCT) event, to be held November ... be able to view live demonstrations of iMedNet ... and learn how iMedNet has been able to ...
(Date:11/4/2015)... New York , November 4, 2015 ... to a new market report published by Transparency Market ... Share, Growth, Trends and Forecast 2015 - 2022", the global ... of US$ 30.3 bn by 2022. The market is ... the forecast period from 2015 to 2022. Rising security ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... and MAGDEBURG, Germany , November 30, 2015 ... in Vienna, Austria to be ... of NeuroRehabilitation (ECNR) in Vienna, Austria ... NovaVision, a wholly owned subsidiary of Vycor Medical, Inc. ("Vycor") ... its Internet-delivered NovaVision Therapy Suite at the 3rd European ...
(Date:11/28/2015)... ... November 28, 2015 , ... • Jeon Jin Bio Corp, ... and rodent control solutions , Bird Free, ... works across all sensory modalities including visual, smell, taste and touch, enabling safe, effective ...
(Date:11/26/2015)... , November 26, 2015 ... --> Accutest Research Laboratories, a ... Research Organization (CRO), has formed a ... Center - Temple Health for joint ... ,     (Photo: ) , ...
(Date:11/25/2015)... BRUSSELS , November 25, 2015 ... la première fois les différences entre les souches ... de celles des êtres humains . Ces ... comprendre et envisager la prise en charge efficace de ... ent diagnostiqués chez les chats .    --> ...
Breaking Biology Technology: