Bone marrow stromal cells of young and adult rats respond similarly to platelet-released supernatant and bone morphogenetic protein-6 in vitro.
BACKGROUND
Age-related changes in periodontal bone regeneration, osseointegration of dental implants, and graft consolidation are increasingly considered in treatment planning. This study was intended to show whether aging is associated with a diminished responsiveness of osteoprogenitor cells to growth and differentiation factors.


METHODS
We compared the capacity of bone marrow stromal cells harvested from young and adult rats to proliferate, migrate, and differentiate into the osteogenic lineage following exposure to platelet-released supernatant (PRS) or bone morphogenetic protein-6 (BMP-6). Bone marrow stromal cells were isolated from 12 young rats aged 6 weeks and 12 adult rats aged 9 months. Proliferation was assessed by 3[H]thymidine incorporation, migration was evaluated with the Boyden chamber assay, and osteogenic differentiation was deduced from alkaline phosphatase activity.


RESULTS
Irrespective of the donor age, bone marrow stromal cells showed increased mitogenic activity and chemotactic motility when exposed to PRS. Adult bone marrow stromal cells had higher alkaline phosphatase activities at baseline and upon incubation with BMP-6 than cells obtained from young animals. There was no difference between the two groups in the slope of the alkaline phosphatase activity curve following stimulation with BMP-6.


CONCLUSIONS
The data demonstrate that, irrespective of their age, bone marrow stromal cells respond similarly to PRS and BMP-6 under in vitro conditions. These findings suggest that osteoprogenitor cells within the bone marrow of adult rats retain their juvenile potential to respond to growth and differentiation factors, which are released naturally or are applied therapeutically at sites of bone regeneration.
Cei
Silvia
S
Oral Surgery Department, University of Pisa, Pisa, Italy.
Kandler
Barbara
B
Fügl
Alexander
A
Gabriele
Mario
M
Hollinger
Jeffrey O
JO
Watzek
Georg
G
Gruber
Reinhard
R
D000375:Aging / Q000502:physiology*; D000469:Alkaline Phosphatase / Q000096:biosynthesis; D000818:Animals; D001854:Bone Marrow Cells / Q000187:drug effects / Q000502:physiology*; D055418:Bone Morphogenetic Protein 6; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology; D001861:Bone Regeneration / Q000502:physiology*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D002633:Chemotaxis; D005260:Female; D059630:Mesenchymal Stem Cells / Q000187:drug effects / Q000502:physiology*; D010006:Osteoblasts / Q000166:cytology*; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D051381:Rats; D018709:Statistics, Nonparametric
C525818:Bmp6 protein, rat; D055418:Bone Morphogenetic Protein 6; D019485:Bone Morphogenetic Proteins; D010982:Platelet-Derived Growth Factor; D000469:Alkaline Phosphatase