Effects of extracts of oxyntic mucosa in rat on the biological activity of osteoblasts.
We explored the relationship between extracts of oxyntic mucosa (EOM) and the biological activity of osteoblasts in rats. We found that EOM could enhance the activity of bone formation in osteoblast. Our results suggest that EOM likely play a role in the cases of osteopenia induced by gastrectomy.


BACKGROUND
Surgical removal of the stomach (gastrectomy) leads to osteopenia in animals and in humans. It was demonstrated that EOM could induce transient hypocalcaemia and stimulate an uptake of Ca(2+) into bone in rats. The main aim of this study has been to clarify whether this procedure was performed through osteoblast, which is responsible for bone formation.


METHODS
Osteoblasts were isolated, cultured, and identified in vitro. Preparing the rats' EOM and diluting into low, middle, and high concentrations, respectively. After osteoblasts were treated by different concentration EOMs or saline (for control), the intracytoplasm [Ca(2+)]i was measured by laser scanning confocal microscopy; the proliferation of osteoblast cells were detected with cell counting kit 8 (CCK-8); and the expressions of collagen type I and osteocalcin were assayed by reverse transcriptase polymerase chain reaction and Western blot.


RESULTS
EOMs were found to induce a dose-related rapid increase of intracytoplasm [Ca(2+)]i in osteoblasts and could stimulate osteoblasts to enhance proliferation and upregulate the expressions of collagen type I and osteocalcin significantly (p < 0.05) compared with the control group.


CONCLUSIONS
It was confirmed that EOM could stimulate osteoblasts to elevate the cytoplasm [Ca(2+)]i and promote the multiplication and the activity of bone formation in osteoblasts.
Spinal Surgeon Department, Southern Medical University, Guangzhou, Guangdong Province, China.
C-Y
CY
Zhao
J-T
JT
Chen
D-H
DH
Yang
Z-M
ZM
Zhong
L
L
Bai
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002457:Cell Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D049109:Cell Proliferation; D002478:Cells, Cultured; D024042:Collagen Type I / Q000096:biosynthesis / Q000235:genetics; D003593:Cytoplasm / Q000378:metabolism; D008297:Male; D008858:Microscopy, Phase-Contrast / Q000379:methods; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D015675:Osteocalcin / Q000096:biosynthesis / Q000235:genetics; D010295:Parietal Cells, Gastric / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D015854:Up-Regulation / Q000187:drug effects
D002457:Cell Extracts; D024042:Collagen Type I; D015675:Osteocalcin; D002118:Calcium