Increased bone resorption by long-term cigarette smoke exposure in animal model
Jader Joel Machado Junqueira,
Juliana Dias Lourenço,
Kaique Rodrigues da Silva,
Vanda Jorgetti,
Rodolfo P. Vieira,
Amanda Aparecida de Araujo,
Kátia De Angelis,
Aristides Tadeu Correia,
Luan Henrique Vasconcelos Alves,
Iolanda de Fátima Lopes Calvo Tibério,
Alexandre Póvoa Barbosa,
Fernanda Degobbi Tenorio Quirino dos Santos Lopes
Affiliations
Jader Joel Machado Junqueira
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil; Corresponding author.
Juliana Dias Lourenço
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Kaique Rodrigues da Silva
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Vanda Jorgetti
Department of Medicine, Laboratory of Renal Physiopathology (LIM-16), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Rodolfo P. Vieira
Post-graduation Program in Sciences of Human Movement and Rehabilitation, Federal University of São Paulo (UNIFESP), Santos, SP, Brazil; Post-graduation Program in Bioengineering, Brasil University, São Paulo, SP, Brazil; Brazilian Institute of Teaching and Research in Pulmonary and Exercise Immunology (IBEPIPE), São José dos Campos, SP, Brazil
Amanda Aparecida de Araujo
Exercise Physiology Laboratory, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
Kátia De Angelis
Exercise Physiology Laboratory, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
Aristides Tadeu Correia
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Luan Henrique Vasconcelos Alves
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Iolanda de Fátima Lopes Calvo Tibério
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Alexandre Póvoa Barbosa
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Fernanda Degobbi Tenorio Quirino dos Santos Lopes
Department of Medicine, Laboratory of Experimental Therapeutics (LIM-20), School of Medicine, University of São Paulo, São Paulo, SP, Brazil
Introduction: 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. Aims: 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. Methods: 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). Results: 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. Conclusion: 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.
