HOME >> BIOLOGY >> NEWS
Pituitary hormone implicated in bone loss after menopause

the fine balance between bone formation and resorption. After menopause, resorption exceeds new bone formation, leading to a net bone loss that can be slowed by estrogen therapy through mechanisms that have remained somewhat murky, Zaidi said.

However, emerging evidence has begun to cast some doubt on whether estrogen deficiency can fully explain bone loss after menopause, he added. For example, mice without an intact pituitary gland become resistant to the effects of ovary loss on bone density. FSH levels also show a closer correlation than estrogen levels to the rate of bone turnover in postmenopausal women.

The researchers now show that mice lacking FSH or its receptor become resistant to bone loss despite severe loss of ovarian function. In mice with normal ovaries and approximately half the normal concentration of FSH, bone mass increased due to a decline in bone resorption by cells known as osteoclasts, which break down bone. Indeed, they report, FSH stimulates receptors found on the surface of bone-degrading osteoclasts and their precursors, leading to the bone cells' formation and function.

The study suggests that FSH plays a role in the normal process by which bone is mobilized by osteoclasts before it can be replaced, Zaidi said.

"As you run or walk throughout life, microcracks develop in bone," he explained. "Therefore, bone remodeling and replacement with new bone is required to maintain skeletal integrity. Osteoclasts essentially dig around those cracks to clear the way for repairs."

In combination with the research group's earlier finding that thyroid-stimulating hormone directly regulates the skeleton, the findings revise the understanding of how pituitary-derived hormones function, Zaidi added. Scientist had thought pituitary hormones acted primarily through their effects on other endocrine glands.

"This should change the textbook picture of pituitary hormone physiology," he said.


'"/>

Contact: Heidi Hardman
hhardman@cell.com
617-397-2879
Cell Press
20-Apr-2006


Page: 1 2

Related biology news :

1. Circadian clock controls plant growth hormone
2. Role of thyroid hormones in slumber under investigation at Rutgers
3. Breast cancer and hormone therapy -- A looking-glass mirror?
4. IMS updated recommendations on postmenopausal hormone therapy
5. Fat tissue-derived hormone leptin increases e-cadherin expression, obesity-breast cancer link noted
6. Steroid hormones regulate the body clock
7. Scientists find hormone activity explains adolescent mood swings
8. Pregnancy hormone increases nerve cells insulation, restores damage
9. Pregnancy hormone key to repairing nerve cell damage
10. Male sweat boosts womens hormone levels
11. Joslin-led study uncovers role of appetite hormone MCH in insulin production

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/9/2016)... leader in attendance control systems is proud to announce the introduction of fingerprint attendance ... the right employees are actually signing in, and to even control the opening of ... ... ... Photo - ...
(Date:6/2/2016)... , June 2, 2016 The ... has awarded the 44 million US Dollar project, for ... Embossed Vehicle Plates including Personalization, Enrolment, and IT Infrastructure ... leader in the production and implementation of Identity Management Solutions. ... January, however Decatur was selected for ...
(Date:5/24/2016)... facilitates superior patient care by providing unparalleled technology to leaders of the medical imaging ... product recently added to the range of products distributed by Ampronix. Photo ... ... ... News ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... -- A person commits a crime, and the detective uses ... criminal down. An outbreak of foodborne illness makes ... uses DNA evidence to track down the bacteria that caused ... not. The FDA has increasingly used a complex, cutting-edge technology ... Put as simply as possible, whole genome sequencing is a ...
(Date:6/23/2016)...  The Prostate Cancer Foundation (PCF) is pleased to announce 24 ... for prostate cancer. Members of the Class of 2016 were selected from a ... Read More About the Class of 2016 PCF Young Investigators ... ... ...
(Date:6/23/2016)... (PRWEB) , ... June 23, 2016 , ... ... today announced the launch of the Supplyframe Design Lab . Located in ... to explore the future of how hardware projects are designed, built and brought ...
(Date:6/23/2016)... 2016 Apellis Pharmaceuticals, Inc. today announced ... of its complement C3 inhibitor, APL-2. The trials ... dose studies designed to assess the safety, tolerability, ... in healthy adult volunteers. Forty subjects ... single dose (ranging from 45 to 1,440mg) or ...
Breaking Biology Technology:
Cached News: