Morpho-functional evaluation of PPARG and IL7 as key molecules related with glycemic and immune alterations in type 2 Diabetes Mellitus and periodontitis

Abstract

It has been more frequent to find patients affected by the combination of Type 2 Diabetes Mellitus (T2DM), Dyslipidemia and Periodontitis (P). There is increasing evidence in the literature in demonstrating interactions between T2DM, dyslipidemia, immune system alterations and Periodontitis. For a better understanding of such interactions, studies with animal models, mainly murine, have been valuable. However, more clinical studies with patients, as well as with murine models, are necessary to know molecules with a key role in the interaction between glycemic and lipid metabolism and the immune system. Moreover, it is important to better understand the interaction between the oral and systemic health of the subject. The role of the Peroxisome Proliferator Activated Receptor (PPARG) Gamma in regulating glycemic, lipid and immune system metabolism, as well as the role of the Interleukin 7 (IL-7) in the immune system, are known, but there are few studies investigating the combined action of these molecules in the modulation of DM2 and Periodontitis. Evidences from the literature and from our previous results (with patients) support our hypothesis that PPARG and IL-7, through TNFA, are key molecules for these pathologies. The general objective of this study is to perform the morpho-functional evaluation of PPARG and IL-7 as key molecules for glycemic and immunological alterations in T2DM and Periodontitis, occurring independently, or as comorbidities. Therefore, our first aim (Objective 1, focusing on a Clinical Study with patients), and the Objective 2 focusing on a Preclinical Murine Model, to allow overcoming the limitations of each experimental design. Methodology of Clinical Study: 30 individuals in each group: T2DM, Periodontitis, Well-controlled T2DM + P, Poorly-controlled T2DM + P, and Control, will have their glycemic, lipid and periodontal profile examined before and after (45, 90, 180 days) of the periodontal treatment. Patients in the Periodontitis and T2DM+P groups will receive non-surgical/surgical periodontal treatment (following criteria in the literature), and individuals in the Control and T2DM groups will receive prophylaxis and reinforcement of oral hygiene instruction (same periods). Murine Model Methodology: 40 male C57BL/6J mice will be evaluated in each group: DM, Periodontitis, DM+P, and control. DM will be induced by the combination of high-fat diet and streptozotocin injection; and Periodontitis will be induced by a combination of ligature and infection by Porphyromonas gingivalis. Ten animals each group will be euthanized (periods: Zero, 7, 14, 21 days of treatment). As the main outcome of the clinical study with patients, the behavior of the key molecules PPARG and IL-7 will be evaluated in all groups and periods, in addition to TNFA, TGFB1 and IL10 by means of their quantification in fluid sulcular gingival (translational levels in periodontium). It is also intended to investigate the systemic transcriptional levels (mRNA in human and murine leukocytes), systemic translational levels (Multiplex in human and murine serum) of these molecules. Patients with indication for treatment that can obtain gingival tissue, as a complementary qualitative analysis, are intended to perform: histological, stereometric and immunohistochemical(IHC) assessment. The main outcome of the preclinical study will be the periodontal bone loss in animals that will be evaluated by micro-CT and IHC analyzes. Linear and/or multiple logistic regressions will be performed, in addition to correlation analyzes of the transcriptional and translational levels of these molecules depending on the glycemic, lipid and periodontal profiles, comparing groups in different periods. Through this clinical study complemented by preclinical (murine) study, we will understand more deeply the pathogenic interaction between DM and Periodontitis, and contribute to biotechnology to identify biomarkers for diagnosis and clinical follow-up of patients. (AU)