Nav: Home

Clarifying the interplay between bone cells in bone remodeling

January 22, 2018

Osaka - Bones are an essential component of our body, with numerous functions that include providing mechanical support of soft tissues, acting as levers for muscle action, and protecting the central nervous system. To accomplish their functions, bones undergo continuous destruction (resorption) carried out by osteoclasts, and formation by osteoblasts.

In the adult skeleton, the two processes must be in balance to maintain a constant, controlled amount of bone. An imbalance in the regulation can result in metabolic bone diseases, such as osteoporosis. Therefore, it is important to understand the spatial-temporal relationship and interaction between osteoblasts and terminally differentiated osteocytes (bone cells) and osteoclasts in vivo. However, it remains controversial whether these cell types physically interact with each other in bone remodeling. A multicenter study centered at Osaka University was conducted to elucidate this knowledge. The findings were recently published in Nature Communications.

"Using an intravital two-photon microscopy technique we developed, we investigated the communication between mature osteoblasts (mOBs) and mature osteoclasts (mOCs) in vivo," study first author Masayuki Furuya explains. "mOBs and mOCs were visualized simultaneously in living skull bone tissues from transgenic mice that express enhanced cyan fluorescent protein (ECFP) driven mOBs and a red fluorescing protein controlled by mOCs."

Intravital two-photon bone imaging is superior compared with conventional analyses of the shape and form of a tissue because it enables two-dimensional scanning in bone in a focal plane to observe cell shapes and the appearance of mOBs and mOCs in the body. Through this visualization method, the researchers successfully captured images of osteoblasts and osteoclasts interacting in real-time in living bone tissue. Next, the number and duration of mOB-mOC contact was analyzed using three-dimensional colocalization. mOBs and mOCs were found to mainly occupy discrete territories in the bone marrow in the steady state, although direct cell-to-cell contact exist in a spatiotemporally limited fashion.

Additionally, using a pH-sensing fluorescence probe, the team found that mOCs secrete protons (subatomic particles with a positive electrical charge) for bone resorption when they are not in contact with mOBs, whereas mOCs contacting mOBs are non-resorptive, suggesting that mOBs can inhibit bone resorption by direct contact.

"Although the molecular mechanisms involved in direct cell contact remain elusive, our study clearly demonstrates an important concept that dynamic communication between mOBs and mOCs regulates bone homeostasis," corresponding author Masaru Ishii says. "Our results have potential to lead to development of a new line of therapy for modifying the association properties of these two cell types, especially in osteoporosis and tumor metastasis in bones."
-end-
Osaka University was founded in 1931 as one of the seven imperial universities of Japan and now has expanded to one of Japan's leading comprehensive universities. The University has now embarked on open research revolution from a position as Japan's most innovative university and among the most innovative institutions in the world according to Reuters 2015 Top 100 Innovative Universities and the Nature Index Innovation 2017. The university's ability to innovate from the stage of fundamental research through the creation of useful technology with economic impact stems from its broad disciplinary spectrum.

Website: http://resou.osaka-u.ac.jp/en/top

Osaka University

Related Osteoporosis Articles:

Mind the (osteoporosis treatment) gap!
A new review, referencing key clinical studies, guidelines and audits, outlines the main global challenges (and their solutions) facing healthcare professionals and policymakers responsible for providing care to populations in relation to bone health and fracture prevention.
Outwitting the 'silent thief' of osteoporosis
In a world first, new Australian research has revealed that genetic profiling can help predict whether an individual will break a bone through osteoporosis.
Osteoporosis: Antibody crystallized
Inhibiting a protein called Sclerostin could probably help treating the bone-loss disease osteoporosis.
JBMR perspective: A crisis in the treatment of osteoporosis
The remarkable progress made over the past 30 years to reduce fractures and dramatically improve the quality of life for millions of osteoporosis patients is rapidly being reversed, say two bone health experts in a Journal of Bone and Mineral Research article published online today.
The developmental origins of osteoporosis
Osteoporosis may have its origins in early life, but the consequences are not apparent until late adult life.
Task force provides guidance on use of osteoporosis drugs
A new report by a task force of the American Society for Bone and Mineral Research provides guidance on the use of bisphosphonates, which are the most commonly used medications for osteoporosis.
Whole genome-sequencing uncovers new genetic cause for osteoporosis
Using one of the world's most extensive genetics data sets, an international research team led by Dr.
Men far less likely to prevent, screen for osteoporosis
While the consequences of osteoporosis are worse in men than women -- including death -- older males are far less likely to take preventive measures against the potentially devastating bone-thinning disease or accept recommendations for screening, according to startling new research by North Shore-LIJ Health System geriatricians.
'Aquatic osteoporosis' jellifying lakes
North American lakes are suffering from declining calcium levels, says new research from Queen's University.
Osteoporosis, not just a woman's disease
While osteoporosis prevention and treatment efforts have historically been focused on post-menopausal women, a new study from Beth Israel Deaconess Medical Center suggests that critical opportunities are being lost by not focusing more attention on bone loss and fracture risk in older men.

Related Osteoporosis Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".