Although DNA can survive only up to 100,000 years and is rarely found in useful quantities in specimens even half that old, the team has found measurable amounts
of osteocalcin in 120,000 - year - old bones.
However, our observation that WBV increases serum
osteocalcin in db / db mice is consistent with the findings of Jing et al. (44).
In the December issue of Geology, the team members report that they isolated a protein
called osteocalcin from the bones and recovered the first intact amino acid sequences from an ancient specimen.
Mice lacking
osteocalcin also had an excess of luteinizing hormone (LH), a pituitary hormone responsible for increasing testosterone production.
The Karsenty lab's data, however, is quite convincing that bone resorption releases functional, hormonally
active osteocalcin in mice.
His team are currently exploring the possibility of
osteocalcin as a treatment option for infertile men.
Serum osteocalcin was also quantified by ELISA (BT - 470; Biomedical Technologies, Stoughton, MA) following manufacturer instructions, as previously described (36).
Osteocalcin from the bones of pregnant mice can penetrate the placenta and help shape fetal brain development, Karsenty and colleagues reported in 2013 in Cell.
As noted previously (12, 16), SED db / db mice in the current study had lower
circulating osteocalcin levels than SED WT mice.
In return, muscles talk back to bones, telling them to churn out
more osteocalcin.
«What interested us was understanding
how osteocalcin becomes active so as to be able to play its role when released into the blood.»
Vitamin K2 supplementation improves insulin sensitivity via
osteocalcin metabolism: a placebo - controlled trial.
Vitamin K2 Supplementation Improves Insulin Sensitivity
via Osteocalcin Metabolism: A Placebo - Controlled Trial
«We demonstrated that when there was no furin in bone cells,
inactive osteocalcin built up and was still released, but this led to an increase in blood glucose levels and a reduction in energy expenditure and insulin production,» Ferron said.
Contamination — one of the biggest concerns with ancient DNA analyses — is also less likely to be a problem
with osteocalcin, because it is found only in vertebrate bones.
Ferron M, Hinoi E, Karsenty G, Ducy P.
Osteocalcin differentially regulates beta cell and adipocyte gene expression and affects the development of metabolic diseases in wild - type mice.
In 2013, a team led by Gerard Karsenty, the Paul A. Marks Professor and chair of the department of genetics and development at Columbia University Medical Center, showed that mice
lacking osteocalcin have major cognitive defects.
Similarly, in the later experiment concerning fertility, only small doses of
uncarboxylated osteocalcin enhanced testosterone production.
Vitamin K: Necessary to
produce osteocalcin, a protein that strengthens the composition of our bones.
It's thought that it controls bone density through Vitamin K2 -
dependent osteocalcin and calcium balance.
Karsenty's team then focused in closer by looking
at osteocalcin — a hormone produced by osteoblasts.
A few years ago, the same group found that
osteocalcin plays a role in maintaining the body's glucose levels (Cell DOI: 10.1016 / j.cell.2007.05.047).
In observational studies of people, it's hard to say that
osteocalcin directly influences blood sugar metabolism when there are so many factors involved.
Because osteocalcin levels in untreated patients with diabetes tend to be low, injections of the protein might alleviate the symptoms of diabetes in humans, an approach Karsenty is testing in mice.
In a recent paper in The Journal of Clinical Investigation, Ferron's team unveiled a new piece of the puzzle that explains how
osteocalcin works.
Furin
causes osteocalcin to become active and the hormone is then released into the blood.
The researchers examined in mice the different enzymes present in cells
where osteocalcin was produced that could be responsible for snipping off the piece in question.
Their stability
makes osteocalcin more likely to endure warmer, harsher environments as well.
Osteocalcin improves nonalcoholic fatty liver disease in mice through activation of Nrf2 and inhibition of JNK
In this study they also identified the receptor that
osteocalcin uses for its functions in the brain — a finding that was confirmed by Kandel's team.
Kandel showed — through a series of tests in mice — that it was almost
certainly osteocalcin, which is secreted by cells in the bone, that regulated the gene's activity.
In postmenopausal American women in the Framingham Offspring Study, for example, which did not account for whether anyone was supplementing with vitamin K, undercarboxylated
osteocalcin ranged from zero to 91 percent, and averaged 17 percent.
Matrix Gla - protein (MGP) helps to prevent vascular calcification by pulling calcium out of soft tissues, while activated
osteocalcin pulls calcium back into the bones and teeth.
Kanazawa I, Tanaka K, Ogawa N, Yamauchi M, Yamaguchi T, Sugimoto T.
Undercarboxylated osteocalcin is positively associated with free testosterone in male patients with type 2 diabetes mellitus.
1)
Does osteocalcin survive the long slow heating involved in making bone broth, or is it destroyed in the process?
On the other hand, the Karsenty team and its collaborators have consistently argued, with strong evidence, that bone resorption is the trigger for release of hormonally active
osteocalcin into the bloodstream.