The influence of cigarette smoke inhalation on bone density: a radiographic study in rats

Abstract

ABSTRACT:The aim of this study was to evaluate the influence of cigarette smoke inhalation (CSI) and its cessation on tibiae bone quality. Forty-one male Wistar rats were randomly assigned to one of the following groups: Group 1 -control (n = 14), Group 2 -3 months of CSI and 2 months without exposure to CSI (n = 12), and Group 3 -5 months of CSI (n = 15). At the end of the experimental period, the animals were sacrificed, the tibiae removed and immediately radiographed for photodensitometric analysis. The results showed that continuous exposure to cigarette smoke promoted a significantly reduced bone density (p < 0.05) (3.22 mm Al eq ± 0.58; 2.93 mm Al eq ± 0.45; 1.86 mm Al eq ± 0.35; for groups 1, 2 and 3, respectively). Similar levels of bone density were observed for the control and cessation groups (groups 1 and 2 -p > 0.05). Thus, within the limits of the present study, it can be concluded that CSI may affect tibiae bone quality, and CSI cessation results in a return towards the level of the control group. DESCRIPTORS: Smoking; Bone density; Rats, Wistar. RESUMO:O objetivo deste estudo foi avaliar a influência da inalação da fumaça de cigarro (IFC) e o efeito de sua interrupção na qualidade óssea da tíbia. Quarenta e um ratos Wistar machos foram aleatoriamente designados a um dos seguintes grupos: Grupo 1 -controle (n = 14), Grupo 2 -3 meses de IFC e 2 meses sem exposição à fumaça (n = 12) e Grupo 3 -5 meses de IFC (n = 15). Ao final do período experimental, os animais foram sacrificados, as tíbias removidas e imediatamente radiografadas para a análise fotodensitométrica. Os resultados mostraram que a exposição contínua à fumaça de cigarro promoveu uma significante redução na densidade óssea (p < 0,05) (3,22 mm Al eq ± 0,58, 2,93 mm Al eq ± 0,45, 1,86 mm Al eq ± 0,35, para os grupos 1, 2 e 3, respectivamente). Níveis semelhantes de densidade óssea foram observados nos grupos controle e interrupção (grupos 1 e 2 -p > 0,05). Portanto, dentro dos limites do presente estudo, pode-se concluir que a IFC pode influenciar a qualidade óssea da tíbia e que a interrupção da inalação parece reverter esse efeito negativo resultando numa densidade óssea semelhante à do grupo controle.

Effect of Epimedium pubescen flavonoid on bone mineral density and biomechanical properties of femoral distal end and femoral diaphysis of passively smoking male rats

“…The measurements performed in the groups of rats exposed to cigarette smoke alone confirmed previous findings that relatively high exposure to cigarette smoke affected the BMD of the femur in rats [22,23]. We demonstrated that the BMD of the distal end and diaphysis of the femur was lower in 4-month smoke-exposed rats than in controls.…”

“…Thus, the beneficial EPF effect on bone turnover during exposure to smoke consisted of stimulating the osteoblastic activity and inhibiting the smoke-stimulated bone resorption. Taking into account the observations made in the present study and the previous reports [22][23][24][25][26][27][28][29][30][31][32][33][34], the protective action of EPF on the skeleton might result from its direct action. This mechanism involved inhibition of bone resorption and stimulation of its formation through a direct influence on both the differentiation and activity of osteoblastic and osteoclastic bone cells.…”

“…We demonstrated that the BMD of the distal end and diaphysis of the femur was lower in 4-month smoke-exposed rats than in controls. César-Neto et al [22] showed that 5-month cigarette smoke inhalation promoted reduced bone density. Hapidin et al [24] demonstrated that 4 months of nicotine treatment was detrimental to bone by causing an increase in the bone resorbing cytokine and cotinine levels, and nicotine also exerted negative effects on the dynamic trabecular histomorphometric parameters in growing rats.…”

“…The biomechanical properties of the femoral diaphysis were not influenced by the bone length and body weight of rats (P [ 0.05). The bone yield load, ultimate load, displacement at yield, displacement at Values are given as mean ± SD (n = 10 in each group) *P \ 0.05 compared to smoke-exposed rats; # P \ 0.05 compared to controls Values are given in mean ± SD (n = 10 in each group) *P \ 0.05 compared to smoke-exposed rats ultimate, stiffness, yield stress, ultimate stress and Young modulus of elasticity were, respectively, 29,22,39,25,36,53,20 and 44 % lower in smoke-exposed compared to control rats. No significant difference in the biomechanical properties of the femoral diaphysis was noted among the controls, 75, 150 and 300 mg/kg/day EPF groups receiving passive smoking.…”

Osseointegration of machined and anodized implants under the influence of nicotine

“…Yet, Cesar-Neto et al 15 , led a radiograph study in 41 male rats Wistar, evaluating the influence in inhalation of cigarette smoke and the effect of its interruption in the tibia bone quality. The results showed that the continuous exposure to cigarette smoke promoted a significant reduction in bone density and the interruption of inhalation seems to reverse this negative effect.…”