A study of bone mineral density and prevalence of osteoporosis in Chinese people of Han nationality from Changchun.

UNLABELLED: We investigated bone mineral density (BMD) and analyzed the changes in peak bone mass and BMD in Chinese Han population. The main results are as follows: (1) The peak BMD in males (0.625 ± 0.109) and females (0.506 ± 0.058) was observed at the age of 30-34 years; (2) osteoporosis prevalence was 7.7% vs. 6.97% in males and females aged 50-59 years; 18.13% vs. 35.97% in males and females aged 60-69 years; 36.41% vs. 59.55% in males and females aged 70-79 years; and 57.53% vs. 75.56% in males and females aged >80 years; (3) BMD differed significantly between genders, and among age groups studied; and (4) peak BMD of Han Chinese was greater than that of Japanese and Danish, as well as ethnicities in China. PURPOSE: The reference data on BMD and osteoporosis among Chinese people are lacking. We, therefore, investigated the BMD and analyzed the changes in peak bone mass and BMD in Han population. METHODS: BMD at the one third of distal radius and ulna of non-dominant forearm was measured by DTX-200 BMD detector in 16,019 Han individuals in Changchun divided into different groups based on age and gender. The mean BMD, T-score, and bone loss rate were analyzed using SPSS 13.0 statistical software. RESULTS: The peak BMD in males and females was 0.625 ± 0.109 and 0.506 ± 0.058, respectively, which was observed in the age group of 30-34 years. BMD decreased gradually after 40 years. The prevalence of osteoporosis was as follows: 7.7% in males and 6.97% in females in the age group of 50-59 years; 18.13% in males and 35.97% in females aged 60-69 years; 36.41% in males and 59.55% in females aged 70-79 years; and 57.53% in males and 75.56% in females aged over 80 years. CONCLUSIONS: There was a significant difference (P < 0.01) in BMD in different age groups and between genders within the same age group. In different age groups, the prevalence of osteoporosis was significantly higher in females than in males (P < 0.01). The peak BMD in this region was higher than that reported in Japan and Denmark, and was comparable to that in Beijing. Furthermore, differences were significant (P < 0.01) as Han population of Changchun was compared with Dai population of Xishuangbanna, Tibet, and Dongxiang population of Gansu province.

Identification of CITED2 as a negative regulator of fracture healing.

The transcription regulator CITED2 (CBP/p300-Interacting-Transactivator-with-ED-rich-tail-2) is known to suppress genes mediating angiogenesis and extracellular matrix (ECM) remodeling. However, it is unclear whether CITED2 has a role in controlling skeletal repair or remodeling. We tested the hypothesis that CITED2 functions in bone fracture healing by suppressing the expression of genes critical to ECM remodeling, angiogenesis and osteogenesis, importantly the matrix metalloproteinases (MMPs). Three hours following mandibular osteotomy or sham surgery of adult rats, osteotomy fronts were harvested and the expression of CITED2 and genes associated with fracture healing was ascertained by quantitative PCR. In parallel, gain-of-function studies examined the effect of overexpressing CITED2 on the expression and activity of several MMPs. In the fractured mandible, CITED2 expression was inversely related to the expression of MMP-2, -3, -9, -13, VEGF, HIF-1alpha, M-CSF, RANK-L, and OPG. Consistent with this, the over-expression of CITED2 in osteoblasts inhibited the expression and activity of MMP-2, -3, -9, and -13. Taken together, the studies suggest that CITED2 is a critical upstream regulator of fracture healing. The suppression of CITED2 early after fracture may allow an optimal initiation of the healing response.