TY - JOUR
T1 - Circulating and skeletal insulin-like growth factor-I (IGF-I) concentrations in two inbred strains of mice with different bone mineral densities
AU - Rosen, C. J.
AU - Dimai, H. P.
AU - Vereault, D.
AU - Donahue, L. R.
AU - Beamer, W. G.
AU - Farley, J.
AU - Linkhart, S.
AU - Linkhart, T.
AU - Mohan, S.
AU - Baylink, D. J.
N1 - Funding Information:
Acknowledgments: This work was supported in part by grants from the National Institutes on Aging (AG10942-0451 \[C.J.R.\],f rom the NIH (Nos. AR-43618 \[W.G.B., L.R.D., and C.J.R.\] and CA-34196 \[W.G.B.\]) and from the U.S. Army Medical Research Acquisition Activity (DAMD17-96-1-6306 \[W.G.B. and D.J.B.\], and by medical research grants from the Department of Veterans Affairs (T.A.L., J.R.F., and D.J.B.).
PY - 1997/9
Y1 - 1997/9
N2 - Recent work has demonstrated differences in femoral bone mineral density between two common inbred strains of mice, C3H/HeJ (C3H) and C57BL/6J (B6), across a wide age range. To investigate one possible mechanism that could affect acquisition and maintenance of bone mass in mice, we studied circulatory and skeletal insulin-like growth factor-I (IGF-I) and femoral bone mineral density (F-BMD) by pQCT in C3H and B6 progenitor strains, as well as serum IGF-I obtained from matings between these two strains and mice bred from subsequent F1 intercrosses (F1). Serum IGF-I measured by radioimmunoassay was more than 35% higher in virgin progenitor C3H than virgin B6 at 1, 4, 8, and 10 months of age, and in 8-month-old C3H compared with B6 retired breeders (p < 0.001). In the progenitors, there was also a strong correlation between serum IGF-I and serum alkaline phosphatase (r = 0.51, p = 0.001). In the 4 month F1 females IGF-I levels and F-BMD were intermediate between C3H and B6 progenitors. In contrast, groups of F1 mice with the highest or lowest BMD also had the highest or lowest serum IGF-I (p = 0.0001). IGF-I accounted for > 35% of the variance in F-BMD among the F1 mice. Conditioned media from newborn C3H calvarial cultures had higher concentrations of IGF-I than media from B6 cultures, and cell layer extracts from C3H calvariae exhibited greater alkaline phosphatase activity than cultures from B6 calvarial cells (p < 0.0001). The skeletal content of IGF-I in C3H tibiae, femorae, and calvariae (6-14 weeks of age) was also significantly higher than IGF-I content in the same bones of the B6 mice (p < 0.05). These data suggest that a possible mechanism for the difference in acquisition and maintenance of bone mass between these two inbred strains is related to systemic and skeletal IGF-I synthesis.
AB - Recent work has demonstrated differences in femoral bone mineral density between two common inbred strains of mice, C3H/HeJ (C3H) and C57BL/6J (B6), across a wide age range. To investigate one possible mechanism that could affect acquisition and maintenance of bone mass in mice, we studied circulatory and skeletal insulin-like growth factor-I (IGF-I) and femoral bone mineral density (F-BMD) by pQCT in C3H and B6 progenitor strains, as well as serum IGF-I obtained from matings between these two strains and mice bred from subsequent F1 intercrosses (F1). Serum IGF-I measured by radioimmunoassay was more than 35% higher in virgin progenitor C3H than virgin B6 at 1, 4, 8, and 10 months of age, and in 8-month-old C3H compared with B6 retired breeders (p < 0.001). In the progenitors, there was also a strong correlation between serum IGF-I and serum alkaline phosphatase (r = 0.51, p = 0.001). In the 4 month F1 females IGF-I levels and F-BMD were intermediate between C3H and B6 progenitors. In contrast, groups of F1 mice with the highest or lowest BMD also had the highest or lowest serum IGF-I (p = 0.0001). IGF-I accounted for > 35% of the variance in F-BMD among the F1 mice. Conditioned media from newborn C3H calvarial cultures had higher concentrations of IGF-I than media from B6 cultures, and cell layer extracts from C3H calvariae exhibited greater alkaline phosphatase activity than cultures from B6 calvarial cells (p < 0.0001). The skeletal content of IGF-I in C3H tibiae, femorae, and calvariae (6-14 weeks of age) was also significantly higher than IGF-I content in the same bones of the B6 mice (p < 0.05). These data suggest that a possible mechanism for the difference in acquisition and maintenance of bone mass between these two inbred strains is related to systemic and skeletal IGF-I synthesis.
KW - Femoral bone density
KW - Insulin-like growth factors
UR - https://www.scopus.com/pages/publications/0030765081
UR - https://www.scopus.com/pages/publications/0030765081#tab=citedBy
U2 - 10.1016/S8756-3282(97)00143-9
DO - 10.1016/S8756-3282(97)00143-9
M3 - Article
C2 - 9276086
SN - 8756-3282
VL - 21
SP - 217
EP - 223
JO - Bone
JF - Bone
IS - 3
ER -