Navigation Links
Abnormal activation of a protein may explain deadly link between high salt intake and obesity
Date:9/19/2011

Bethesda, Md. (Sept. 19, 2011) Dietary salt intake and obesity are two important risk factors in the development of high blood pressure. Each packs its own punch, but when combined, they deliver more damage to the heart and kidneys than the sum of their individual contributions. Discovering the molecular mechanisms behind this lethal synergy has presented a challenge to scientists, but research led by Toshiro Fujita, MD, professor and chairman of the Department of Internal Medicine and chief of the Department of Nephrology and Endocrinology at the University of Tokyo, suggests that high dietary salt intake and obesity work together to trigger an abnormal activation of a cellular protein called Rac1.

How Obesity and a High-Salt Diet Team Up

Dr. Fujita's team studied the effects of a high-salt diet in rats bred to have high blood pressure and different levels of blood pressure sensitivity to salt. When obese "salt-sensitive" rats were fed a high-salt diet, the team found that Rac1 activated the mineralocorticoid receptor (MR) on the rats' kidney cells. This receptor is normally activated by the hormone aldosterone. When turned on, MR leads to the expression of a protein called epithelial sodium channel (ENaC) and an enzyme called the sodium pump. Both of these substances promote the reabsorption of salt, which causes the body to retain fluid and results in high blood pressure. This is the first time scientists have seen Rac1 usurp aldosterone's role in activating MR in the regulation of blood pressure. The protein's usual duties entail regulating an array of cellular events such as cell growth.

The team made the discovery when attempting to treat the obese, hypertensive rats with drugs designed to block MR activation and inhibit Rac1. When Rac1 inhibitors were successful in lowering the rats' blood pressure, the team knew they had discovered a mechanism by which obesity and a high-salt diet team up to wreak havoc on blood pressure and the kidneys.

Importance of the Findings

According to Dr. Fujita, the team's findings carry important implications for the treatment of hypertension. "Our data indicate that the Rac1-mediated pathway in the kidneys can be an alternative therapeutic target for salt-sensitive hypertension and salt-mediated kidney injury," he said. "Based upon our results, we can speculate that Rac1 in the kidneys regulates salt susceptibility of blood pressure, and that Rac1 inhibitors, as well as MR antagonists, may be effective in the treatment of salt-sensitive hypertension."


'/>"/>

Contact: Donna Krupa
dkrupa@the-aps.org
7-301-634-7209
American Physiological Society
Source:Eurekalert

Related biology news :

1. Study finds chronic abnormal brain blood flow in Gulf War veterans
2. BMC awarded NIH grant to study brain abnormalities in former ELGANS patients
3. Early embryos can correct genetic abnormalities during development
4. Could ovarian stimulation cause an increase in oocyte chromosome abnormalities?
5. Electronic tracking system can improve follow-up after an abnormal Pap test
6. UT MD Anderson study ties abnormal cells in blood to lung cancer
7. Brain abnormalities in Parkinsons patients develop before symptoms occur
8. New chromosomal abnormality identified in leukemia associated with Down syndrome
9. Abnormal brain circuits may prevent movement disorder
10. New test can detect both genetic and chromosomal abnormalities in embryos
11. High carbon dioxide levels cause abnormally large fish ear bones
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/25/2017)... , Jan. 25, 2017 The Elements of ... (IAM) lifecycle is comprised of a comprehensive set ... purpose of maintaining digital identities and providing a ... applications. There are significant number of programs opted ... to time by optimizing processes and changing policies. ...
(Date:1/24/2017)... Jan. 24, 2017  It sounds simple and ... that monitors vital signs and alerts parents on ... oxygen saturation level drops. But pediatric experts argue ... parents, with no evidence of medical benefits, especially ... marketed aggressively to parents of healthy babies, promising ...
(Date:1/21/2017)... Research and Markets has announced the addition of the ... offering. ... global voice recognition biometrics market to grow at a CAGR of ... the present scenario and the growth prospects of the global voice ... report considers the revenue generated from the sales of voice recognition ...
Breaking Biology News(10 mins):
(Date:2/24/2017)...  OncoSec Medical Incorporated ("OncoSec") (NASDAQ: ONCS), a company ... Opinion Leader event to highlight new clinical data that ... at the upcoming 2017 ASCO-SITC Immuno-Oncology Symposium and the ... held in-person and via live webcast on Tuesday, February ... at the Lotte New York Palace Hotel in ...
(Date:2/23/2017)... TORONTO , Feb. 23, 2017 /PRNewswire/ - The ... Institute for Cancer Research (OICR) are pleased to report ... Series A financing, with Johnson & Johnson Innovation – ... investors include venture groups HealthCap, TPG Biotechnology Partners, and ... ...
(Date:2/23/2017)... 23, 2017  Imanis Life Sciences announced today ... oncolytic vaccinia viruses for virotherapy research. These viruses ... Genelux,s proprietary, vaccinia virus-based technology platform for research ... into a partnership with Genelux to offer researchers, ... for use in research," said Dr. Kah ...
(Date:2/23/2017)... ... February 23, 2017 , ... Today, researchers ... CRP, adiponectin, uric acid, and/or other biomarkers or SNPs of interest) using one, ... Salimetrics’ SalivaLab , the relationship between insulin and other relevant biomarkers can be ...
Breaking Biology Technology: