Featured Research

from universities, journals, and other organizations

Could diabetes be in your bones? Link between metabolic disease, bone mass; Breakdown of bone keeps blood sugar in check

Date:
July 22, 2010
Source:
Cell Press
Summary:
Our bones have much greater influence on the rest of our bodies than they are often given credit for, according to two new studies. Both studies offer new insights into the interplay between bone and blood sugar, based on signals sent via insulin and a bone-derived hormone known as osteocalcin.

Insulin signaling in bone favors whole-body glucose homeostasis by activating osteocalcin. (1) Insulin signals osteoblasts, bone cells responsible for bone formation, which (2) tell osteoclasts, bone cells responsible for resorption, to destroy old bone. Next (3), the acidic (low pH) conditions created by the osteoclasts activates osteocalcin inside the bone. Finally (4), the active osteocalcin released from bone travels to the pancreas and stimulates the release of more insulin.
Credit: Image provided by Columbia University Medical Center

Our bones have much greater influence on the rest of our bodies than they are often given credit for, according to two new studies in the July 23 issue of Cell, a Cell Press publication. Both studies offer new insights into the interplay between bone and blood sugar, based on signals sent via insulin and a bone-derived hormone known as osteocalcin.

Related Articles


Mice whose bones can't respond to insulin develop high blood sugar and insulin resistance, both hallmarks of diabetes. Those symptoms are tied to a drop in osteocalcin. The findings suggest that osteocalcin, or perhaps a drug that targets bone, might hold promise in fighting the global epidemic of type 2 diabetes, according to the researchers.

"Our study reveals a key molecular link between bone remodeling and metabolism," said Gerard Karsenty of Columbia University.

"Bone is an organ that has to pay attention to where calories are going," added Thomas Clemens of Johns Hopkins University School of Medicine. "It talks to muscle, fat, the pancreas. It's a player in energy metabolism."

And perhaps that makes a lot of sense, Karsenty said. The remodeling of bone relies on two cell types, bone-building osteoblasts and bone-resorbing osteoclasts, making bone the only organ with a cell type that is entirely focused on destroying host tissue. "On a daily basis, the formation of bone is expensive in terms of energy," he said.

In fact, the idea that the skeleton is much more than a reservoir for calcium and phosphate isn't entirely new, the researchers said. Earlier evidence by Karsenty's group had shown links between bone and the fat hormone leptin. (Obese adults are significantly less likely to develop osteoporosis.)

Scientists also had evidence that osteoblasts might respond to insulin in important ways. Osteoblasts bear insulin receptors and when treated with insulin show signs of collagen synthesis and take up more glucose, Clemens' team notes. People with type 1 diabetes due to a lack of insulin can also develop weakened bones.

Karsenty's team describes bone as a multitasker. It has mechanical, hematopoietic (blood-producing) and metabolic functions. It also acts as an endocrine organ through the release of osteocalcin hormone, which favors glucose metabolism when in its active form.

Still, Clemens said he was surprised by what they saw after developing a mouse lacking insulin receptors only in their osteoblasts. "The mice started to get fat," he said. They showed changes in their biochemistry that were consistent with insulin resistance. They also had low osteocalcin levels and fewer osteoblasts to produce less bone.

With age, the animals became even fatter and developed more marked high blood sugar accompanied by severe glucose intolerance and insulin resistance. Those symptoms improved with osteocalcin treatment.

Karsenty's group presents independent evidence for the important role of insulin in bone for keeping glucose in check through osteocalcin, in what he refers to as a "feed-forward loop." But his group goes a step further to suggest that bone-resorbing osteoclasts (not just osteoblasts) have a place in this too.

Karsenty explains that bone-building osteoblasts actually control bone resorption by osteoclasts, a process that takes place under very acidic conditions. Those conditions would also favor the chemical modification necessary to produce active osteocalcin, which can escape bone to act as a hormone.

That could be important to those who take osteoporosis drugs designed to block bone resorption, Karsenty suggests. "It's a red flag," he said. "Osteoporotic patients treated with [bone resorption inhibitors] may be at risk of glucose intolerance."

The researchers include Mathieu Ferron, Columbia University, New York, NY; Jianwen Wei, Columbia University, New York, NY; Tatsuya Yoshizawa, Columbia University, New York, NY; Andrea Del Fattore, University of L'Aquila, L'Aquila, Italy; Ronald A. DePinho, Harvard Medical School, Boston, MA; Anna Teti, University of L'Aquila, L'Aquila, Italy; Patricia Ducy, Columbia University, New York, NY; and Gerard Karsenty, Columbia University, New York, NY.


Story Source:

The above story is based on materials provided by Cell Press. Note: Materials may be edited for content and length.


Journal References:

  1. Mathieu Ferron, Jianwen Wei, Tatsuya Yoshizawa, Andrea Del Fattore, Ronald A. DePinho, Anna Teti, Patricia Ducy, Gerard Karsenty. Insulin Signaling in Osteoblasts Integrates Bone Remodeling and Energy Metabolism. Cell, 2010; DOI: 10.1016/j.cell.2010.06.003
  2. Keertik Fulzele, Ryan C. Riddle, Douglas J. DiGirolamo, Xuemei Cao, Chao Wan, Dongquan Chen, Marie-Claude Faugere, Susan Aja, Mehboob A. Hussain, Jens C. Brüning, Thomas L. Clemens. Insulin Receptor Signaling in Osteoblasts Regulates Postnatal Bone Acquisition and Body Composition. Cell, 2010; DOI: 10.1016/j.cell.2010.06.002

Cite This Page:

Cell Press. "Could diabetes be in your bones? Link between metabolic disease, bone mass; Breakdown of bone keeps blood sugar in check." ScienceDaily. ScienceDaily, 22 July 2010. <www.sciencedaily.com/releases/2010/07/100722132334.htm>.
Cell Press. (2010, July 22). Could diabetes be in your bones? Link between metabolic disease, bone mass; Breakdown of bone keeps blood sugar in check. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2010/07/100722132334.htm
Cell Press. "Could diabetes be in your bones? Link between metabolic disease, bone mass; Breakdown of bone keeps blood sugar in check." ScienceDaily. www.sciencedaily.com/releases/2010/07/100722132334.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) — It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) — More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) — In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) — A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins