Efeitos da terapia fotodinâmica com aluminio – cloro ftalocianina sobre a peroxidação lipídica e produtos antioxidantes em tecidos inflamados animais

Photodynamic therapy (PDT) consists of a non-toxic photosensitizing agent (FS) administration followed by a laser source resulting in a sequence of photochemical and photobiological processes that generate reactive oxygen species (ROS) that damaging cells. The present work evaluated the effects of PDT nanoemulsion-aluminum chloride phthalocyanine (AlClFc) mediated on malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels, which represent indicators involved in oxidative stress and antioxidant defenses. For this purpose, this study used 120 female rats of the Rattus norvegicus species, Wistar race, divided into 5 groups: Healthy (H), with periodontal disease (PD), with periodontal disease and treatment with FS (F), with periodontal disease and treatment with the laser (L); and periodontal disease and treatment with PDT (FL). An experimental model for represent periodontal disease (PD) was induced by ligature (split-mouth). Seven days later the induction of PD, the treatments were instituted according to the groups. In the group treated with PDT was applied 40μl FS (5μM) followed by laser irradiation diode InGaAlP (660nm, 100J / cm2). The rats were sacrificed on the 7th and 28th day after treatment and tissue specimens were removed and subjected to histological, immunohistochemical methods and enzymatic colorimetric measurements with detection by UV / VIS spectroscopy. Inflammatory changes, connective tissue disorganization and alveolar bone loss were displaying in groups with PD induced. The enzyme dosages showed that MDA levels were higher in PD induced groups, with no statistically significant differences (p> 0.05). High levels of GSH were found in groups L (p = 0.028) and FL (p = 0.028) compared with PD group, with statistically significant differences. Immunohistochemistry for SOD showed higher immunostaining in L and FL groups, compared to the PD group without statistically significant differences (p> 0.05). GPx showed lower immunoreactivity in the DP group when compared to the other groups and statistically significant differences were observed between the DPxL groups (p <0.05). TFD administered in this experiment did not induce elevation of MDA levels significantly increased the GSH levels and showed intense immunostaining pada SOD and GPx, showing that this therapy does not accentuated lipid peroxidation, however, it was able to induce effects on the antioxidant defenses processes. The LBI therapy appeared to show photomodulatory promoting effects reduction of the MDA levels, increasing GSH levels and with intense immunostaining for SOD and GPx, demonstrating that laser therapy induced antioxidant effects.

Efeitos da azilsartana sobre a doença periodontal em um modelo experimental com ratos wistar

Periodontal diseases, highly prevalent disease in worldwide population, manifest primarily in two distinct entities: plaque-induced gingivitis and periodontitis. Periodontitis is a chronic inflammatory disease characterized of different levels of collagen, cementum, and alveolar bone destruction. Recent experimental studies demonstrated anti-inflammatory and antirreabsortive effect of antihypertensive agents of the angiotensin II receptor blockers class on periodontal disease. The aim of this study was to evaluate the effects of azilsartan (AZT), a potent inhibitor of the angiotensin II receptor which has minimal adverse effects on bone loss, inflammation, and the expression of matrix metallo proteinases (MMPs), receptor activator of nuclear factor kB ligand (RANKL), receptor activator of nuclear factor kB (RANK), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2), and cathepsin K in periodontal tissue in a rat model of ligature-induced periodontitis. Male Wistar albino rats were randomly divided into 5 groups of 20 rats each: (1) nonligated, water; (2) ligated, water; (3) ligated, 1 mg/kg AZT; (4) ligated, 5 mg/kg AZT; and (5) ligated, 10 mg/kg AZT. All groups were treated with water or AZT for 10 days. Periodontal tissues were analyzed by morphometric exam, histopathology and immunohistochemical detection of MMP-2, MMP-9, COX-2, RANKL, RANK, OPG, and cathepsin K. Levels of IL-1b, IL-10, TNF-a, myeloperoxidase (MPO), and glutathione (GSH) were determined by ELISA. Treatment with 5 mg/kg AZT resulted in reduced MPO (p˂0.05) and IL-1b (p˂0.05) levels and increased in Il-10 levels (p˂0.05). It was observed a reduced expression of MMP-2, MMP-9, COX-2, RANK, RANKL, cathepsin K, and a increased expression of OPG in the animals subjected to experimental periodontitis and threated with AZT (5 mg/kg). Conclusions: These findings suggest an anti-inflammatory and anti-reabsortive effects of AZT on ligature-induced periodontitis in rats.

Resposta celular Th1 /Th2 na doença periodontal experimental, em ratos: um estudo imuno-histoquímico

Host response plays a major role in the pathogenesis of periodontal disease. Mediators such as inflammatory cytokines which are secreted during the immune response to bacterial challenges have ambiguous functions that may or may not lead to protection of the attacked tissue. In this context, experimental evidence suggests that T-helper 1 (Th-1) and T-helper 2 (Th-2) mediated responses are potentially important during the disease process. The aims of this study therefore were to further clarify the role played by Th2 cells during different time points of the active phase of periodontal disease, as well as, to investigate whether there was any evidence of a Th1 response in the periodontal disease microenvironment. Experimental periodontitis was induced in 30 Wistar male rats by placing cotton ligatures around the mandibular first molars. The rats were then randomly divided into two groups. Group1 (G1=15) and Group 2 (G2=15). In G1 the ligatures were maintained for 2 days, whereas in G2 the ligatures were left for 15 days, a time point that corresponds to the advanced stage of periodontal disease The contra-lateral teeth served as controls (no ligatures). Immunohistochemical investigation for the presence in gingival tissue of Th2 specific transcription factor (GATA3) and the subunit of the IFN-γ receptor was carried out after the disease induction period. Light microscopy analysis revealed a decrease in the expression of GATA-3 as bone loss progressed. On the other hand, although IFN-γ R1 was detected at an early stage of the active phase of disease its expression remained unaltered during the remaining period of the study. These results indicate that the Th2 response have a protective role during the pathogenesis of periodontal disease and that the progression of the periodontal disease is related with the unbalance of the responses Th1/Th2

Análise imuno-histoquímica das metaloproteinases da matriz ( MMP-1,MMP-2 e MMP-9) na doença periodontal

The tissular destruction found in periodontal diseases is caused mainly by components of the host that have its production stimulated by the products of the microorganisms present on the plaque. Matrix Metalloproteinases (MMPs), a class of enzymes involved both in physiologic and pathologic extracellular matrix degradation are considered the main responsible for the characteristic tissular loss in periodontal disease, and the understanding of how this happens can have a series of beneficial implications for prevention, diagnosis and treatment of this illness. The aim of this work was to study the immunohistochemical expression of MMP-1, MMP-2, and MMP-9 in fragments of gingival biopsies with clinical diagnose of periodontal disease. MMP-1 has expressed significantly more than the others MMPs in gingivitis both in the epithelium (p=0,0008) and connective tissue (p=0,0049). In periodontitis, both MMP-1 and MMP-9 has expressed significantly more than MMP-2 in the epithelium (p<0,0001) and in the connective tissue (p=0,0002). MMP-1 and MMP-9 presented more expression in periodontitis than in gingivitis but MMP-1 only in the connective tissue (p=0,03) and MMP-9 in the epithelium (p=0,003) and in the connective tissue (p=0,04). In conclusion, these results indicate that the MMP-1 presents high expression in every stages of the periodontal diseases, and increases its expression in the connective tissue when the gingivitis evolves to periodontitis. Therefore, it may have an important role in connective tissue degradation and bone loss observed in disease, since early, in gingivitis, until late stages, in periodontitis, of the periodontal disease. MMP-9 has expressed more in periodontitis than in gingivitis, both in epithelium and in connective tissue. It means that this enzyme may have some importance in the progression of gingivitis to periodontitis by acting in bone resorption observed in this desease

Avaliação da desadaptação das selas de próteses parciais removíveis após 1 a 5 anos de uso

The non-adaptation of the removable partial prosthesis (RPP) base to fibromucosal tissue is caused by resorption of residual ridges (RRR). The onset of bone resorption, which occurs after tooth extraction and continues throughout life, is accelerated by local or systemic factors. Aim: Assess the degree of non-adaptation of removable partial prosthesis saddles and the factors that influence it. Methodology: A sectional study was conducted with 81 patients using RPP who had their prostheses installed between 2003 and 2007 (1 to 5 years of use) at the Faculty of Dentistry of the Universidade Federal do Rio Grande do Norte (UFRN). After anamnese and clinical examination, a cast was made with polyether-based material, using the base of the prosthesis to make the impression. The base of the saddle was loaded with the casting material and positioned in the mouth, applying pressure on the supports. After polymerization, the material was removed from the saddle and measurements were taken at 3 different points using a pachymeter. Results: The non-adaptation of the saddle increased significantly with years of use (p = 0.005). The tooth-tissue supported prostheses obtained higher mean non-adaptation values than those of tooth supported prostheses (p < 0.001). Flaccid mucosa showed the worst non-adaptation results, which were statistically different from resilient mucosa (p < 0.001). The greater the extension of the saddle, the greater the non-adaptation (p < 0.001). The natural tooth antagonistic arch yielded better results than did RPP and total prosthesis (p < 0.001). Saddle non-adaptation at the free end was less near the pillar tooth and greater in the more posterior region (p < 0.001). When adaptation of the supports to the niches was poor, greater saddle non-adaptation occurred than when it was good or fair (p < 0.001). Saddles located in the posterior region of the arch had greater non-adaptation than those in the anterior region (p = 0.023). Conclusion: The mean non-adaptation of the saddle to the residual ridges was 0.27 mm. It can be concluded that, even with the use of RPP, bone height reduction was slight within the 1-5-year period of use. The following are factors that influence adaptation of the RPP saddle base: years of use, age, force transmission path to the alveolar bone, location of the toothless area, antagonistic arch, type of mucosa, adaptation of supports to the niche and extension of the saddle

Influência do tamoxifeno associado ao diabete melito na densidade mineral óssea

Considering that osteopenia and osteoporosis are diabetes mellitus complications, and that tamoxifen (TAM) is an anti-estrogenic drug used in breast cancer treatment, this drug may have a beneficial action preventing accentuaded bone loss associated to diabetes. Female Wistar rats (n=60) weighting 180-250g were divided in four groups: Group C, control animals (n=5); Group T, animals treated with TAM (n=5); Group D, diabetic animals (n=5); and Group DT, diabetic animals treated with TAM (n=5). Oestrus cycle was evaluated before the beggining of experimental period to select the animals with regular cycle. This evaluation continued throughout the study period and for all studied groups. Diabetes was induced by a intra perithoneal injection of streptozotocin (STZ) in a concentration of 45 mg/Kg of body weight. Those animals with serum glicose levels 250 mg/dL were considered diabetics. Animals were sacrificed in the periods of 30, 60 and 90 days after diabetes onset. Left femur histomorphometric measurements and serum biochemical analysis (glycemia, alkaline phosphatase, tartaric-resistant acid phosphatase, calcium, phosphorous, magnesium, total proteins, albumin, globulins, urea and creatinine) were done. Histomorphometric results showed a progressive bone loss in Group D animals when compared to those from Group C all over the experimental period, becoming accentuaded in the 90 days period. In relation to Groups T and DT, values approcimated to those obtained for control group were found during the whole period of study. Those data may indicate a bone mass recovery or a diminished bone loss due to diabetes when animals were treated with TAM. During the whole experimental period animals of groups D and DT maintained glycemic levels above 250 mg/dL whereas animals of groups C and T maintained those levels below 150mg/dL. Alkaline phosphatase activity was increased in all study periods for groups D and DT when compared to group C animals over the 90 days period. Tartarate-resistant acid phosphatase activity was showed unaltered in all periods of study and for all groups. Calcium and magnesium results were also unaltered, maintaining reference levels for all groups in all experimental periods. Phosphorous levels were increased in groups D and DT when compared to groups C and T in the 30 days period. However no difference was found in the periods of 60 and 90 days for this test. No difference was found for total proteins levels for groups C, T, D and DT over the study period. Albumin levels were reduced in DT group in the 60 days period and in D and DT groups in the 90 days period. Urea levels were significantly increased in the 30, 60 and 90 days study periods in groups D and DT when compared to groups C and T. Creatinine results showed a significantly increase in the 90 days period for groups D and DT when compared to groups C and T, and maintaining unaltered in the 30 and 60 days periods. These results suggest that the treatment with TAM may reduce bone loss caused by diabetes mellitus

Perfil periodontal de pacientes portadores de alterações endócrino-metabólicas

Objective- Convinced that periodontium, many times, can show alterations in human health, the aim of these studies was to investigate the periodontal situation in patients with endocrine-metabolic disorders such as, Berardinelli-Seip Syndrome, hyperthyroidism, hypothyroidism and acromegaly. Methods- Eight patients with Berardinelli-Seip Syndrome, 16 acromegalics, 30 hypothyroids, 30 hyperthyroids, and a control group with 35 patients were evaluated. Clinical attachment loss, probing depth, gingival bleeding index, gingival overgrowth and Index of Decayed, Missing and Filled Teeth were measured in each patient. All ethical aspects were rigidly observed, being the study conducted after its approval by the University of Fortaleza Research Ethics Committee. Results- The presence of periodontitis was marked in hyperthyroids and in patients with Berardinelli-Seip Syndrome. Hypothyroids showed not much presence of periodontitis, while all acromegalics presented absence of periodontitis. Conclusions- The protective effect of periodontitis in acromegalic patients is a new finding, whose mechanisms are not yet clear, but may be related to the anabolic effects of growth hormone. The presence of periodontitis in Berardinelli-Seip Syndrome may occur due the early onset of diabetes. In hyperthyroids, the high prevalence of periodontitis could be linked to thyroid hormones effects on bone, explaining also the minor prevalence in hypothyroids

Imunoexpressão de fatores reguladores da osteoclastogênese na doença periodontal em humanos e sua relação com os parâmetros clínicos

Periodontal disease is an infection initiated by oral periodontal pathogens that trigger an immune response culminating in tissue destruction. This destruction is mediated by the host by inducing the production and activation of lytic enzymes, cytokines and the stimulation of osteoclastogenesis. The aim of this study was to compare the immunohistochemical expression of factors involved in bone resorption, RANKL (Ligand Receptor Activator of Nuclear Factor kappa B), OPG (Osteoprotegerin) and TNF-α (tumor necrosis factor alpha) between the gingival healthy, gingivitis and chronic periodontitis and correlate them with clinical parameters. The sample consisted of 83 cases and 12 clinically healthy gums, 42 gingivitis and 29 periodontitis, from 74 adolescent and adult patients with a mean age of 35 years, without systemic changes and non-smokers, predominantly female and race brown. There was no statistically significant difference for the expression of anti-RANKL (p = 0.581) and RANKL / OPG ratio (p = 0.334) when comparing the three conditions, but the anti-OPG and anti-TNF-α showed statistically significant between the types of injury (p = 0.001 and p <0.001, respectively), showing greatest expression in periodontitis. In cases of periodontitis, the variable clinical attachment loss (PIC) was statistically significant and positive correlation, respectively, with immunostaining of anti-RANKL (p = 0.002, p = 0.001 and r = 0.642), anti-OPG (p = 0.018, p = 0.014 and r = 0.451), anti-TNF-α (p = 0.032, p = 0.014 and r = 0.453) and the percentage ratio of RANKL / OPG (p = 0.018, p = 0.002 and r = 0.544). The tooth mobility (MB) showed a statistically significant difference only with immunohistochemical anti-RANKL (p = 0.026), and probing depth (PD) was positively correlated with anti-RANKL (p = 0.028 and r = 0.409), both in cases of periodontitis. Only in cases of gingivitis TNF-α was positively correlated with RANKL (p = 0.012 and r = 0.384) and the RANKL / OPG ratio (p = 0.027 and r = 0.341). Given these results, we conclude that the greatest expression of TNF-α in periodontitis demonstrates a relationship with the progression and severity of periodontal disease and the correlation between all antibodies and clinical attachment loss demonstrates their involvement in periodontal bone resorption