Effects of periodontitis on the development of asthma: The role of photodynamic therapy

Abstract

To evaluate whether periodontitis modulates lung inflammation in an experimental model of asthma as well as the photodynamic therapy (PDT) is associated with a reduction of lung inflammation. Seventy-two BALB/c male mice (~2 months) were randomly divided into 8 groups (n = 9): Basal, Periodontitis (P), P+PT, P+PT+PDT, Asthma (A), A+P, A+P+PT, and A+P+PT+PDT. Periodontitis was induced by using the ligature technique and asthma was induced by ovalbumin (OVA). PT was performed with curettes and PDT with methylene blue (0.005%), λ = 660nm, with a radiant exposure of 318J/cm2. After 43 days, euthanasia was carried out prior to lung and mandible morphological analyzes. All of the manipulations of the animals were performed by only one operator. The total and differential cell counts and cytokines IL-4, IL-5, IL-10, IFN-γ, TNF-α, IL-1β, and IL-6 were evaluated in the bronchoalveolar lavage (BAL) and in the serum. Mucus and alkaline phosphatase were also quantified. Statistical analyzes were performed by a blinded statistician. One-way analysis of variance (ANOVA) was employed, followed by the Student-Newman-Keuls test. Periodontitis group (P) increased alkaline phosphatase and bone resorption (p<0.05), validating the experimental model of periodontitis. The A group and the P group increased the total amount of cells (p <0.05) in the BAL. However, in the A+P group, there was a decrease in these cells, except for in the A+P+PT+PDT group (p<0.05). The asthma group increased the Th2 cytokines and P group increased the Th1 cytokine profile, and A+P+PT+PDT group increased IL-10 cytokine. Mucus was increased for the A and P groups. In conclusion, periodontitis in the asthmatic mice reduced the inflammatory migrated cells in the BAL (eosinophils, lymphocytes, macrophages). In addition, it reduced the levels of the IL-4 and TNF-α cytokines, which was also accompanied by a decreased mucus production. After PDT treatment the total cell count increased however, this increase was not accompanied by a pro-inflammatory cytokines release. Only in PDT group the anti-inflammatory IL-10 was increased. Further studies are needed to understand this mechanism of action.

Effect of poor oral health on respiratory functions which is one of the important factor of sportive performance

“…In asthmatic mice, an increase in the number of macrophages, lymphocytes, neutrophils, and eosinophils was found after conventional periodontal therapy. These results indicated that photodynamic therapy could induce a cellular immune response as shown by some other studies (31). Several studies have been performed to explain the role of oral bacteria in the pathogenesis of respiratory tract infections.…”

Prevotella intermedia and periodontitis are associated with severe asthma

“…While this increased chance of asthma occurring in individuals with periodontitis has been T A B L E 2 Characteristics related to lifestyle and oral health conditions in individuals with severe asthma (case) and without asthma (control): corroborated by previous studies, 12,20 some studies were unable to identify this association, 21,22 or found an inverse association. The frequency of periodontitis in individuals with severe asthma was >3 times higher than in participants without this respiratory disease.…”

“…The frequency of periodontitis in individuals with severe asthma was >3 times higher than in participants without this respiratory disease. While this increased chance of asthma occurring in individuals with periodontitis has been T A B L E 2 Characteristics related to lifestyle and oral health conditions in individuals with severe asthma (case) and without asthma (control): corroborated by previous studies, 12,20 some studies were unable to identify this association, 21,22 or found an inverse association. 23,24 In accordance with the conceptual framework, the confounders were used to adjust the final association measurements to neutralize the influence of these covariables in the relationship between periodontitis and severe asthma.…”

Evaluation of photodynamic therapy in pericoronitis

“…The red light will act to improve tissue repair and decrease the periodontal inflammatory process, especially on facial swelling and trismus [22] and also will modulate the immunoinflammatory response of the host, interfering in the levels of inflammatory cytokines. Corrêa et al, [13] Candeo et al, [9] and Kellesarian et al [17] found a reduction of the pro-inflammatory cytokines IL1-β, IL-6, IL-8, and TNF-α after the PDT. So we will try to verify if PDT will promote advantageous modulation of cytokine levels in pericoronitis.…”

“…PDT relies on the appropriate combination of light, PS, and oxygen. [9] Light reach the PS at the target cell in the presence of oxygen, leading to PS excitation. [10] The singlet excited state PS molecules can be converted to a triplet excited state by intersystem crossing.…”