Effect of physical exercise on the regulation of inflammatory markers of apical periodontitis: a molecular study in rats

• Grant number: 23/11282-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2023
• End date: September 30, 2024
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Gisele Faria
• Grantee: Elda Olivia Nobre de Souza
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Apical periodontitis (AP) is characterized by inflammation and destruction ofmineralized and non-mineralized periapical tissues due to an immune-inflammatoryresponse to root canal infection. Considering that physical exercise (PE) positivelymodulates the individual's immune-inflammatory response, it becomes important toinvestigate the relationship between PE and AP. Therefore, the aim of this study is toevaluate the effect of PE on the regulation of inflammatory markers of AP, in rats. Fortymale Holtzman rats will be distributed into 4 groups (n=10/group): with PE and APinduction, with PE and without AP, sedentary with AP induction, and sedentary withoutAP. The experimental protocol will be carried out in 2 consecutive phases: (1) 8 weeksof treadmill running (or sedentary routine) and (2) AP induction with maintenance of thepulp chamber open to the oral environment for 3 weeks (21 days), during which theanimals will maintain training (or remain sedentary, in the case of the untrained group)completing a total of 11 weeks of experiment. All groups will be submitted to a test todetermine the maximum physical capacity (Tmax) at the week 0 (to determine thetraining intensity), and weeks 4 and 8 (to adjust the training intensity and evaluate theeffectiveness of the training protocol), and at the end of week 11 (to assess physicalperformance). For the PE groups, the animals will be submitted to aerobic treadmillrunning exercise, with moderate intensity (60% of Tmax), 1 hour a day, 5 days a week,for 11 weeks. AP will be induced by a coronal opening of the upper and lower molarsfrom the left side. After euthanasia, the left hemi-jaws will be removed and the roots ofthe 1st and 2nd molars and adjacent bone will be collected en bloc and prepared forthe analysis of gene expression levels of inflammatory and osteoclastogenesis factors(Nfatc1, IL-1 ², IL- 6, IL-10, TNF-±, RANKL, OPG, cathepsin K, GAPDH and ²-actin) byquantitative real-time polymerase chain reaction (RT-qPCR). Statistical tests will bechosen according to the distribution and homoscedasticity of the data and asignificance level of 5% will be used.