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PURPOSE: This study evaluated the systemic and local effects of doxycycline (DOX) and low-intensity laser (LIL) treatment as adjuvants to scaling and root planing (SRP) in the treatment of experimental periodontitis in rats. METHODS: The sample consisted of 180 male rats (Rattus norvegicus albinus, Wistar), of which 30 did not receive induction of periodontal disease (negative control [NC] group) and 150 received induction of periodontal disease in the lower first molar. After 7 days, the ligature was removed, and the animals were divided into the following groups: NT (no treatment), SRP (SRP), DOX (SRP and DOX irrigation), LIL (SRP and laser irradiation), and DOX+LIL (SRP, DOX, and LIL). The animals were euthanized at 7, 15, and 30 days; thereafter, biochemical, radiographic, histological, and immunohistochemical analyses were performed. RESULTS: In the intragroup analysis, lower concentrations of α-1-glycoprotein acid (α-1-Ga) and complement 3 (C3) were observed in the DOX+LIL group than in all other groups at all time points, as well as lower levels of complement 4 (C4) at 15 and 30 days (P<0.001). Less bone loss was observed in the DOX, LIL, and DOX+LIL groups than in the NC and SRP groups at all time points (P<0.001). There was a smaller number of tartrate-resistant acid phosphatase (TRAP)-positive cells in the DOX+LIL group than in the other groups at all time points (P<0.001). Positive correlations were observed between the systemic levels of α-1-Ga, C3, and C4 and the number of TRAP-positive cells. CONCLUSIONS: The combination of DOX with LIL as SRP adjuvants was effective both systemically and locally for the treatment of experimental periodontitis in rats.

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This study aims to evaluate the effects of photobiomodulation (PBM) on human monocytes, assessing the oxidative burst and ultimate fungicidal potential of these cells, as well as the gene expression at the mRNA level of CD68, CD80, CD163, CD204, IL-6, TNF-α and IL-10 in derived macrophages. Primary cultures of human monocytes were irradiated with an InGaAlP (660 nm)/GaAlAs (780 nm) diode laser (parameters: 40 mW, 0.04 cm2, 1 W/cm2; doses: 200, 400 and 600 J/cm2). Cells were submitted to the chemiluminescence assay, and a microbicidal activity assay against Candida albicans was performed. Reactive oxygen species (ROS) and nitric oxide (NO) production were measured, and cell viability was assessed by the exclusion method using 0.2% Trypan blue reagent. Irradiated monocytes were cultured for 72 h towards differentiation into macrophages. Total RNA was extracted, submitted to reverse transcription and real-time PCR. The results were analysed by ANOVA and the Tukey test (α = 0.05). Irradiated monocytes revealed a significant increase in their intracellular and extracellular ROS (P < 0.001). The 660 nm wavelength and 400 J/cm2 dose were the most relevant parameters (P < 0.001). The fungicidal capacity of the monocytes was shown to be greatly increased after PBM (P < 0.001). PBM increased the expression of TNF-α (P = 0.0302) and the production of NO (P < 0.05) and did not impair monocyte viability. PBM induces a pro-inflammatory Th1-driven response in monocytes and macrophages.

Assuntos

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This study evaluated the influence of Doxycycline (DOX) and Low-Intensity Laser (LIL) (InGaAlP diode laser) as scaling and root planing (SRP) adjuvants in the treatment of periodontitis induced in rats. The rats received periodontal disease induction, and after 7 days, the ligature was removed, and the animals were divided into groups/treatments: NT-receive no treatment; SRP-submitted only to SRP; DOX-submitted to SRP and DOX irrigation; LIL-submitted to SRP and LIL irradiation; and DOX + LIL-submitted to SRP treatments, DOX irrigation and LIL irradiation. The animals were sacrificed at 7, 15 and 30 days, and then, the analyses were performed. A lower concentration of Alpha-glycoprotein acid and Complement 3 was observed in the DOX + LIL group compared to all the other groups in all the periods, and for Complement 4 at 15 and 30 days (P < 0.01). A lower bone loss (BL) was observed in the DOX + LIL group compared to all the other groups in all the periods (P < 0.01). It can be concluded that LIL was effective in the reduction of proteins, and its association with DOX was effective in the reduction of proteins and BL, in the treatment of periodontal induction in rats.

Assuntos

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Background and aims: Lipopolysaccharide (LPS), an endotoxin, is a component of the outer membrane of Gram-negative bacteria that is able to activate the peripheral immune system, leading to changes in signalling pathways that act locally and systemically to achieve adaptive responses. Sickness behaviour is a motivational state in response to endotoxin exposure and includes depressed activity and a reduction of exploratory behaviour, potentially reorganising organism priorities to cope with infectious diseases. We hypothesised that 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol) modulates the leukocyte response to endotoxins and decreases LPS-induced sickness behaviour in mice.Methods: The effects of Tempol on LPS-induced peritonitis and the respiratory burst of neutrophils primed with LPS and triggered by phorbol 12-myristate-13-acetate (PMA) were evaluated. To evaluate the effects of Tempol on sickness behaviour, the mice were submitted to an open field and forced swim tests.Results: Tempol (50-100 µM/106 cells) decreased the respiratory burst of LPS-primed and PMA-stimulated neutrophils in vitro. In vivo, this nitroxide (30 and 100 mg/kg body weight) inhibited leukocyte migration to the peritoneal cavity after LPS administration in mice. Moreover, Tempol pretreatment (30 and 100 mg/kg body weight) before LPS administration also attenuated sickness behavioural changes.Conclusions: Together, these findings shed light on the mechanisms underlying the anti-inflammatory potential and confirm the therapeutic potential of nitroxides.

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The purpose of this study was to assess, for the very first time, the effects of photodynamic therapy (PDT) on Schistosoma mansoni in vitro by measuring reactive oxygen species (ROS) generation throughout the treatment, as well as the behavior of the parasites (mating, motility and contraction/shortening), and damage to their tegument and excretory systems. The parasites were divided into 4 groups: control, photosensitizer, laser and PDT. Light irradiation was delivered with an InGaAlP low-level laser device operating at 660nm, with 40mW and 100J/cm2. For PDT, different toluidine blue dye (TBO) concentrations and times of exposure were utilized. Interestingly, TBO-mediated PDT was able to kill S. mansoni (P<0.001) due to the significant amount of ROS released that inflicted damages in the tegument and excretory system, as well as contraction and cessation of motility. In addition, males of S. mansoni were shown to be more sensitive to PDT if compared to their corresponding females when the optimal TBO concentration of 31.2µL was considered (P=0.0126). PDT presents two major advantages: not inducing microbial resistance and also lacking adverse effects. Therefore, PDT may become a promising therapeutic alternative for schistosomiasis in the near future, especially for cases of allergy and resistance to praziquantel.

Assuntos

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OBJECTIVE: The aim of this study was to evaluate low-level laser therapy (LLLT) as an adjuvant treatment for scaling and root planing (SRP) for the treatment of induced periodontitis in simvastatin-modified rats. MATERIAL AND METHODS: A total of 180 rats were evenly divided into two groups: Veh - receiving oral administration of polyethylene glycol (vehicle); S - receiving oral administration of Simvastatin. Periodontal disease was induced in both groups at the first mandibular molar. After seven days, the ligature was removed and the animals were divided into subgroups according to the following local treatments: NT - no treatment; SRP - scaling and root planing and irrigation with saline solution; and LLLT ¬- SRP and laser irradiation (660 nm; 0.03 W; 4 J). Ten animals in each subgroup/local treatment were euthanized at 7, 15 and 30 days. Samples of gingival tissue were processed to analyze the tissue oxidative damage and radiographic analysis. Levels of oxidative stress were analyzed by the expressions of Tripeptideglutathione (TG), Malondialdehyde (MDA) and Carbonylated Proteins (CP). RESULTS: The animals in S group had higher levels of TG and lower levels of MDA and CP compared with Veh group (p<0.05). Radiographically, in the intragroup analysis Veh and S, LLLT showed lower bone loss (BL) compared with NT and SRP, in all experimental periods (p<0.01). In addition, a lower BL was observed for the animals of Veh group treated with LLLT compared with treatment SRP in the S group, in all experimental periods. CONCLUSION: Within the limits of this study, we can conclude that LLLT was effective as adjuvant treatment for SRP protecting against the occurrence of oxidative tissue damages as well as for reducing alveolar bone loss in experimentally induced periodontitis simvastatin-modified rats.

Assuntos

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Abstract Low intensity laser can be used as a promising alternative in the treatment of periodontal disease. Objective The aim of this study was to evaluate low-level laser therapy (LLLT) as an adjuvant treatment for scaling and root planing (SRP) for the treatment of induced periodontitis in simvastatin-modified rats. Material and Methods A total of 180 rats were evenly divided into two groups: Veh - receiving oral administration of polyethylene glycol (vehicle); S - receiving oral administration of Simvastatin. Periodontal disease was induced in both groups at the first mandibular molar. After seven days, the ligature was removed and the animals were divided into subgroups according to the following local treatments: NT - no treatment; SRP - scaling and root planing and irrigation with saline solution; and LLLT ¬- SRP and laser irradiation (660 nm; 0.03 W; 4 J). Ten animals in each subgroup/local treatment were euthanized at 7, 15 and 30 days. Samples of gingival tissue were processed to analyze the tissue oxidative damage and radiographic analysis. Levels of oxidative stress were analyzed by the expressions of Tripeptideglutathione (TG), Malondialdehyde (MDA) and Carbonylated Proteins (CP). Results The animals in S group had higher levels of TG and lower levels of MDA and CP compared with Veh group (p<0.05). Radiographically, in the intragroup analysis Veh and S, LLLT showed lower bone loss (BL) compared with NT and SRP, in all experimental periods (p<0.01). In addition, a lower BL was observed for the animals of Veh group treated with LLLT compared with treatment SRP in the S group, in all experimental periods. Conclusion Within the limits of this study, we can conclude that LLLT was effective as adjuvant treatment for SRP protecting against the occurrence of oxidative tissue damages as well as for reducing alveolar bone loss in experimentally induced periodontitis simvastatin-modified rats.

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BACKGROUND AND AIM: Oxidative stress arising from inflammatory processes is a serious cause of cell and tissue damage. Tempol is an efficient antioxidant with superoxide dismutase-like activity. The purpose of this paper is to address the inhibition of protein disulfide isomerase (PDI), an essential redox chaperone whose active sites contain the Cys-Gly-His-Cys (CXXC) motif, by the nitroxide Tempol. RESULTS: In the presence of Tempol (5-120 µM), the reductase activity of PDI was reversibly affected both in vitro and in activated mice neutrophils, with an IC50 of 22.9 ± 10.8 µM. Inhibitory activity was confirmed by using both the insulin method and fluorescent formation of eosin-glutathione (E-GSH). The capacity of Tempol to bind the enzyme was determined by EPR and mass spectrometry. EPR Tempol signal decreased in the presence of PDI while remained unaffected when PDI thiols were previously blocked with NEM. When total protein was analyzed, 1 and 4 molecules of Tempol were bound to the protein. However, only one was found to be covalently bound to PDI at the a'active site. More specifically, Cys400 was modified by Tempol. CONCLUSION: We have shown that the nitroxide Tempol acts as an inhibitor of PDI through covalent binding to the Cys400 of the protein structure. Since PDI is coupled with the assembly of the NADPH oxidase complex of phagocytes, these findings reveal a novel action of Tempol that presents potential clinical applications for therapeutic intervention to target PDI knockdown in pathological processes in which this protein is engaged.

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OBJECTIVE: The objective of this study was to evaluate the local effects of statins as adjuvants for treatment by scaling and root planing (SRP) of periodontal disease induced in rats. MATERIAL AND METHODS: Ninety rats were used in the present experiment. Periodontal disease was induced in all animals using a cotton thread placed in the left first mandibular molar. After 7 days of induction, the bandage was removed and the animals were divided into three groups: 1) NT group (n=30), no treatment; 2) SRP group (n=30): SRP and irrigation with control gel; 3) S group (n=30) - SRP and irrigation with Simvastatin. Ten animals from each group were euthanized at 7, 15 and 30 days after treatment. Gingival biopsy specimens were processed to analyze the expression of matrix metalloproteinase 8 (MMP-8). The mandibles were removed and submitted to radiographic and laboratory processing for histometric analysis. RESULTS: The S group showed a significantly lower expression of MMP-8 compared to NT and SRP groups in all experimental periods. In the radiographic and histometric analyses between the groups, S group showed a significantly lower bone loss (BL) compared to NT and SRP groups in all experimental periods. CONCLUSIONS: Within the limits of this study, it can be concluded that locally applied statin was effective as an adjuvant treatment for SRP in rats with induced periodontal disease.

Assuntos

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Abstract Objective The objective of this study was to evaluate the local effects of statins as adjuvants for treatment by scaling and root planing (SRP) of periodontal disease induced in rats. Material and Methods Ninety rats were used in the present experiment. Periodontal disease was induced in all animals using a cotton thread placed in the left first mandibular molar. After 7 days of induction, the bandage was removed and the animals were divided into three groups: 1) NT group (n=30), no treatment; 2) SRP group (n=30): SRP and irrigation with control gel; 3) S group (n=30) - SRP and irrigation with Simvastatin. Ten animals from each group were euthanized at 7, 15 and 30 days after treatment. Gingival biopsy specimens were processed to analyze the expression of matrix metalloproteinase 8 (MMP-8). The mandibles were removed and submitted to radiographic and laboratory processing for histometric analysis. Results The S group showed a significantly lower expression of MMP-8 compared to NT and SRP groups in all experimental periods. In the radiographic and histometric analyses between the groups, S group showed a significantly lower bone loss (BL) compared to NT and SRP groups in all experimental periods. Conclusions Within the limits of this study, it can be concluded that locally applied statin was effective as an adjuvant treatment for SRP in rats with induced periodontal disease.

Assuntos