Purpose: To evaluate the effect of long-term low or high-dose nicotine exposure on bone mass via measuring bone mineral density (BMD) and oxidant-antioxidant status markers.
Methods: Thirty-five female Swiss Albino rats weighing 70 ± 10 g were divided as the control group (n = 12), low-dose nicotine group (n = 12) and high-dose nicotine group (n = 11). While the control group was given only normal drinking water, the low-dose nicotine group had 0.4 mg/kg per day and the high-dose nicotine group, 6.0 mg/kg per day of nicotine added to their water for the period of 1 year. BMD was determined with X-ray absorptiometry of lumbar vertebra, corpus femoris, proximal and distal femur. To evaluate oxidant-antioxidant status malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activities were determined.
Results: When comparing the nicotine groups and controls, neither BMD nor oxidant-antioxidant status markers showed any statistically significant difference. In comparison to the controls, 12 months of high-dose oral nicotine exposure did not have a significant effect on BMD and low-dose nicotine exposure led to a statistically insignificant increase in BMD.
Conclusions: Contrary to common belief, the results of this study show that nicotine is not responsible for the decrease in BMD leading to osteoporosis frequently seen in smokers. However, there is a need to explore the other harmful materials in tobacco which may be responsible for the alterations seen in BMD of smokers.