Effects of probiotic therapy on experimental periodontitis in rats fed with a high-fat diet

Abstract

In the last few years, there has been a considerable interest in the concept of modulating theintestinal microbiota through the use of specific bacteria in order to improve the hostmetabolism. Some pre-clinical and clinical studies have demonstrated that the use ofprobiotics can be a promising therapeutic/preventive alternative to Metabolic Syndrome (MS)and periodontal disease (PD). These conditions are deeply associated and affect millions ofpeople worldwide. Until this moment, there are no studies evaluating the impact of theprobiotic therapy on the association MS-PD. The purpose of this study is to evaluate thepotential effects of the probiotic agent Bifidobacterium animalis subsp. lactis HN019 on theprogression and development of experimental periodontitis associated or not with the co-morbidities of MS in Sprague-Dawley rats. 40 Sprague-Dawley rats (MSSD) and 32 normalmale Sprague-Dawley rats (SD) will be used. They will be randomly assigned to groups withligature-induced PD and control groups (C), with no induction of PD. Each one of this groupswill be subdivided into 2 subgroups according to the dietary protocol: i) Groups MSSD-C andSD-C (rats without PD - n = 18); ii) Groups MSSD-PROB and SD-PROB (rats without PDand treated with probiotic - n = 18); iii) Groups MSSD-PD and SD-PD (rats with PD - n =18); iv) Groups MSSD-PD-PROB and SD-PD-PROB (rats with PD and treated with probiotic- n = 18). PD will be induced through the placement of ligatures around the mandibular firstmolars of each animal for 14 days. The SM will be induced by the consumption of hyperlipiddiet (60% fat), which will be started 8 weeks before probiotic therapy and will continue untilthe day of euthanasia. PD will be induced by placing ligatures for 14 days in the lower firstmolars of each animal. The probiotic strain will be daily added to the water of the animals for8 weeks. All animals will be euthanized 16 weeks after the start of the study. The followingparameters will be evaluated: i) metabolic parameters and levels of pro and anti-inflammatorycytokines through immunoenzymatic assays (ELISA and LuminexTM xMAP®); ii) levels ofalveolar bone and attachment losses through histomorphometric analysis; iii) bone volume(micro-CT); iv) gut microbiological profile (qRT-PCR). Data will be statistically analyzed (p0.05).Key words: Rats, metabolic syndrome, periodontitis, probiotics. (AU)