Ar. Villanueva et al., NUCLEAR PROFILE AREA OF OSTEOBLASTS IN NORMAL, OSTEOPOROTIC, AND FLUORIDE-TREATED SUBJECTS, Journal of histotechnology, 19(4), 1996, pp. 313-315
Osteoblasts undergo changes both in shape (progressive flattening) and
function (progressive decline in matrix synthesis) during their life
span. Nuclear volume, apart from changing systematically during their
cell cycle, is believed to be a general index of cell vigor. According
ly, we measured the nuclear profile area of osteoblasts classified as
pre (Group I), cuboidal (Group II), intermediate (Group III), and term
inal (Group IV) in iliac cancellous bone in 6 premenopausal normals, m
ean age in years (SD) 40.2 (4.8), 5 postmenopausal normals, age 65.8 (
2.4), 15 postmenopausal osteoporotics, age 65.3 (4.9), 5 patients with
fluoride-induced osteomalacia, age 69.2 (5.0), and two patients with
endemic fluorosis, age 70.5 (5.5). A total number of 4,085 osteoblast
nuclei were examined and measured. In each group there was a systemati
c decline in nuclear profile area through stages I-IV, corresponding t
o an average decline in nuclear volume of greater than 90%. The major
difference among groups was that in type II (cuboidal) osteoblasts, nu
clear profile area was significantly greater in premenopausal normals
than in the other four groups, which did not differ significantly. The
effect seems to be related to age, rather than to disease or treatmen
t. The functional significance of this age-related morphologic change
remains to be determined, but it may be related to the decline in appo
sition rate with age.