Effect of nitric oxide donor nitroglycerin on bone mineral density in a rat model of estrogen deficiency-induced osteopenia

Introduction: Estrogen deficiency leads to bone mass loss and increased risk for osteoporosis. The aim of this study was to examine influence of cigarette smoking on bone mineral density in postmenopausal women with estrogen deficiency in menstrual history.Methods: The total of 100 postmenopausal women living in Sarajevo area, aged 50-65 years, with estrogen deficiency in menstrual history participated in this prospective study. The subjects were divided in two groups, examination and control group, based on bone mineral density values. The women in the examination group had osteoporosis while in the control group were women with osteopenia or normal bone mineral density. Bone mineral density was measured at the lumbar spine and proximal femur by Dual–Energy X–ray Absorptiometry using Hologic QDR-4000 scanner. Smoking habits were assessed for each subject.Results: The average number of cigarettes smoked per day in women with estrogen deficiency in menstrual history was 14.86 in the examination group and 4.67 in the control group. The difference in the average number of cigarettes smoked per day between the two groups was statistically significant (p <0.01). The coefficient of linear correlation between T score and the number of cigarettes smoked per day among women with estrogen deficiency in menstrual history in the examination group was statistically significant (p<0.01). The coefficient of linear correlation between T score and the number of cigarettes smoked per day among women with estrogen deficiency in menstrual history in the control group was statistically significant ( p<0.05).Conclusion: Results of this study suggest that cigarette smoking has negative impact on bone mineral density and that healthy lifestyle (no smoking) has the potential to reduce bone loss in postmenopausal women with estrogen deficiency in menstrual history.

Download Full-text

Regionally specific compensation for bone loss in the tibial trabeculae of estrogen-deficient rats

Acta Radiologica ◽

10.1080/02841850701283761 ◽

2007 ◽

Vol 48 (5) ◽

pp. 531-539 ◽

Cited By ~ 26

Author(s):

Z. F. Sheng ◽

R. C. Dai ◽

X. P. Wu ◽

L. N. Fang ◽

H. J. Fan ◽

...

Keyword(s):

Bone Mineral Density ◽

Bone Loss ◽

Bone Mineral ◽

Estrogen Deficiency ◽

Sprague Dawley ◽

Micro Computed Tomography ◽

Mineral Density ◽

Trabecular Thickness ◽

Sprague Dawley Rats ◽

Rat Tibia

Background: Bone mineral density (BMD) and microstructural variations have been extensively investigated in recent years; however, the compensation for bone loss between different regions is still unclear. Purpose: To fully characterize regional variations in bone mineral density (BMD) as well as the microstructure and dynamic changes of rat tibial trabeculae that occur with bone loss associated with estrogen deficiency. Material and Methods: Female Sprague-Dawley rats were ovariectomized (OVX), sham-operated (sham), or left unoperated (baseline control). The left tibiae were harvested at baseline, and at postoperative weeks 3 and 15. High-resolution micro-computed tomography (µCT) was used to identify the densitometric and microstructural properties of trabeculae in the proximal ends of the rat tibia, specifically the epiphysis and metaphysis. Results: Volumetric BMDs at the organ (organ BMD) and tissue (tissue BMD) levels were significantly higher for trabeculae at the epiphysis than metaphysis. Moreover, trabeculae at the epiphysis were thicker, and fewer in number and connectivity than those at the metaphysis, which were more rod like. Trabeculae at the metaphysis were more susceptible to bone loss induced by estrogen deprivation than at the epiphysis, and the regions varied greatly in their adaptation to this loss. At the metaphysis, trabecular tissue BMD and thickness were unexpectedly higher at postoperative week 15 than week 3 or baseline. In contrast, at the epiphysis, tissue BMD did not change with time, but trabecular thickness significantly increased at week 15 compared to baseline and was also greater in OVX compared to sham rats. Conclusion: Metaphyseal and epiphyseal trabeculae show regionally specific variations in BMD and microstructure. The former are more susceptible to bone loss induced by estrogen deficiency and would be strengthened by either hypertrophy or hypermineralization, while epiphyseal trabeculae are mainly strengthened by thickening.

Download Full-text