Increased bone resorption by long-term cigarette smoke exposure in animal model

• Published in: Heliyon Vol. 7; no. 12; p. e08587
• Main Authors: Junqueira, Jader Joel Machado, Lourenço, Juliana Dias, da Silva, Kaique Rodrigues, Jorgetti, Vanda, Vieira, Rodolfo P., de Araujo, Amanda Aparecida, De Angelis, Kátia, Correia, Aristides Tadeu, Alves, Luan Henrique Vasconcelos, Tibério, Iolanda de Fátima Lopes Calvo, Barbosa, Alexandre Póvoa, Lopes, Fernanda Degobbi Tenorio Quirino dos Santos
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-12-2021; Elsevier
• Subjects: Bone matrix; Bone remodeling; Oxidative stress; Smoking; Oxidative stress; Bone remodeling; Bone matrix; Smoking
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2021.e08587

Clinical and experimental studies have been attesting the deleterious effects of smoking mainly due to the stimulation of osteoclastogenesis and inhibition of osteoblastogenesis. However the physiological mechanisms that can explain these changes are not fully understood.
To evaluate the trabecular bone resorption effect caused by long-term exposure to cigarette smoke and the action of cytokines and reactive oxygen species involved in this process.
Sixty young adult C57BL/6 mice were allocated to two groups: control, 30 animals exposed to filtered air for 1, 3 and 6 months; and smoke, 30 animals exposed to cigarette smoke for 1, 3 and 6 months. Femoral and tibial extraction was performed to evaluate the bone mineral matrix, bone cytokines (Receptor activator of nuclear factor-kappa B ligand - RANKL and Osteoprotegerin - OPG) and oxidative stress markers (Thiobarbituric acid reactive substances - Tbars).
Exposure to cigarette smoke (CS) generated changes in bone structural parameters in the 6th month of follow-up, demonstrating an evident bone loss; reduction in OPG/RANKL ratio from the 3rd month on and increase in Tbars in the first month, both closely related to the increase in osteoclastogenic activity and bone resorption.
These findings reinforce the importance of CS-induced oxidative stress in bone compromising the bone cellular activities with a consequent impairment in bone turn over and changes in bone structure.
Smoking; Bone remodeling; Bone matrix; Oxidative stress.