Osteoclast and osteoblast, both remodel the bone, one breaks and other makes respectively.

Osteocytes are simply those osteoblasts stuck in extracellular matrix they secrete. They are connected by long branches (cell extensions) and make network via gap junctions.

Thank you Dr. Subhash C. Juneja for the answer, however I am still wondering when stress and strain happened what will happened... as a Wolf"s Law, when forces(stress&strain) come through to bone (Long bone e.g. Tibia) some cells must sense it some should order to pre-osteoclast to changed to Osteoclast and the process should be go on from activation stage to resorption and reversal and formation

But which cell is the major one to sense this forces and then to response to it firstly

Osteoblasts do respond to surface strains and texture, and deposit a mineralizable matrix accordingly. In the main, osteocytes transduce mechancial strain from the bone to the canalicular processes via tethers and fluid flow through the canalicular/lacunar space. When strain thresholds for a specific bone and location are exceeded, the "message" from the osteocytic syncytium out to the surface of the bone is to recruit osteoblasts to build up bone mass. If the strain is persistently below the threshold, the "message" goes out to the surface from the osteocytic syncytium to permit osteoclast access to the space below the bone lining cells and to remove bone mass. This is a very finely tuned energetics conservatism.

Thank you Dr. @Timothy G. Bromage

And I wish I can find the recent article about this. Cause we think that it maybe more complicated than the human knowledge.

I really appreciate for your respons. Best wishes.

I wish I find a relevant article.

Hoping these papers will help: Article Osteocytes and the bone lacunar-canalicular system: Insights...

Article Cell Death in Chondrocytes, Osteoblasts, and Osteocytes

Article The Role of Osteocytes in Age-Related Bone Loss

Article Aging, Osteocytes, and Mechanotransduction

Thank u so much

Lara Pizzorno

I will check them out and we can share our opinion after all, again.

i think all have an effective work

I think they are the osteocytes, although to date their function is not perfectly known, although they are known to control the extracellular concentration of Ca2 + and phosphates.

They express moleulas like DMP1, FGF23 and sclerostin that control the bone formation

Jilka RL, O'Brien CA Role of Osteocytes in Age-Related Bone Loss.Curr Osteoporos Rep. 2016 Feb;14(1):16-25. doi: 10.1007/s11914-016-0297-0.

Thank you Dr. @Edgar Nieto. Most if the people believe that it is octeocyte, however, I guess it needs more research to find out, the real mechanism of them.

Dear Amir. It is possible to find some explaation in these investigations, Edgar

The Role of the Osteocyte in Bone and Nonbone Disease.Bonewald LF et al. Endocrinol Metab Clin North Am. (2017)

Ma L, Hua R, Tian Y, Cheng H, Fajardo RJ, Pearson JJ, Guda T, Shropshire DB, Gu S, Jiang JX. 43 hemichannels protect bone loss during estrogen deficiency.

Bone Res. 2019 Apr 22;7:11. doi: 10.1038/s41413-019-0050-2

Michigami T, Ozono K. Roles of Phosphate in Skeleton.

Front Endocrinol (Lausanne). 2019 Mar 26;10:180. doi: 10.3389/fendo.2019.00180

Atkinson EG, Delgado-Calle J. Emerging Role of Osteocytes in Cancer in Bone.

JBMR Plus. 2019 Feb 27;3(3):e10186. doi: 10.1002/jbm4.10186

As several have already mentioned, it is becoming more clear that osteocytes regulate the function of other bone cells. Once thought to be essentially functionless, it is now known that osteocytes sense deformation of bone (mechanical force) through fluid contained in the lacunocanalicular system. Many believe that this is through shear stress on the osteocyte membrane, but it is becoming more clear that there are "transverse tethering elements" that span the canalicular space, attaching the bone matrix to the osteocyte membrane. As fluid moves through this space, it drags on the tethers and "tugs" on the cell membrane to transmit force to the osteocyte. This initiates downstream signals (many of which remain undefined) but ultimately leads to decreases in RANKL secretion (leading to less osteoclast formation) and decreased Sclerostin, a negative regulator of osteoblast formation. Thus, through release of RANKL and Sclerostin, osteocytes regulate both osteoclasts and osteoblasts respectively. Of course, this is not the whole story. There are likely many other factors involved, but it's a snapshot that allows for a general understanding of how these cells coordinate signaling and function.

@william_r_thompson

Dear william

Thank you so much. As you mentioned the process it is correct and it is what human knows about this process

I am appreciate for your accurate answer.