Hypertrophy of the right ventricle by pulmonary artery banding in rats: a study of structural, functional, and transcriptomics alterations in the right and left ventricles.

Introduction: Right ventricular remodeling with subsequent functional impairment can occur in some clinical conditions in adults and children. The triggering factors, molecular mechanisms, and, especially, the evolution over time are still not well known. Left ventricular (LV) changes associated with right ventricular (RV) remodeling are also poorly understood. Objectives: The study aimed to evaluate RV morphological, functional, and gene expression parameters in rats submitted to pulmonary artery banding compared to control rats, with the temporal evolution of these parameters, and to analyze the influence of RV remodeling by pulmonary artery banding in rats and their controls over time on LV geometry, histology, gene expression, and functional performance. Methods: Healthy 6-week-old male Wistar-EPM rats weighing 170-200 g were included. One day after the echocardiogram, depending on the animals undergoing the pulmonary artery banding (PAB) procedure or not (control group), they were then randomly divided into subgroups according to the follow-up time: 72 h, or 2, 4, 6, or 8 weeks. In each subgroup, the following were conducted: a new echocardiogram, a hemodynamic study, the collection of material for morphological analysis (hypertrophy and fibrosis), and molecular biology (gene expression). The results were presented as the mean ± standard deviation of the mean. A two-way ANOVA and Tukey post-test compared the variables of the subgroups and evolution follow-up times. The adopted significance level was 5%. Results: There was no significant difference among the subgroups in the percentage of water in both the lungs and the liver (the percentage of water in the lungs ranged from 76% to 78% and that of the liver ranged from 67% to 71%). The weight of the right chambers was significantly higher in PAB animals in all subgroups (RV PAB weighed from 0.34 to 0.48 g, and control subjects, from 0.17 to 0.20 g; right atrium (RA) with PAB from 0.09 to 0.14 g; and control subjects from 0.02 to 0.03 g). In the RV of PAB animals, there was a significant increase in myocyte nuclear volume (97 µm3-183.6 µm3) compared to control subjects (34.2 µm3-57.2 µm3), which was more intense in subgroups with shorter PAB follow-up time, and the fibrosis percentage (5.9%-10.4% vs. 0.96%-1.18%) was higher as the PAB follow-up time was longer. In the echocardiography result, there was a significant increase in myocardial thickness in all PAB groups (0.09-0.11 cm compared to control subjects-0.04-0.05 cm), but there was no variation in RV diastolic diameter. From 2 to 8 weeks of PAB, the S-wave (S') (0.031 cm/s and 0.040 cm/s), and fractional area change (FAC) (51%-56%), RV systolic function parameters were significantly lower than those of the respective control subjects (0.040 cm/s to 0.050 cm/s and 61%-67%). Furthermore, higher expression of genes related to hypertrophy and extracellular matrix in the initial subgroups and apoptosis genes in the longer follow-up PAB subgroups were observed in RV. On the other hand, LV weight was not different between animals with and without PAB. The nuclear volume of the PAB animals was greater than that of the control subjects (74 µm3-136 µm3; 40.8 µm3-46.9 µm3), and the percentage of fibrosis was significantly higher in the 4- and 8-week PAB groups (1.2% and 2.2%) compared to the control subjects (0.4% and 0.7%). Echocardiography showed that the diastolic diameter and LV myocardial thickness were not different between PAB animals and control subjects. Measurements of isovolumetric relaxation time and E-wave deceleration time at the echocardiography were different between PAB animals and control subjects in all subgroups, but there were no changes in diastolic function in the hemodynamic study. There was also increased expression of genes related to various functions, particularly hypertrophy. Conclusion: 1) Rats submitted to pulmonary artery banding presented RV remodeling compatible with hypertrophy. Such alterations were mediated by increased gene expression and functional alterations, which coincide with the onset of fibrosis. 2) Structural changes of the RV, such as weight, myocardial thickness, myocyte nuclear volume, and degree of fibrosis, were modified according to the time of exposure to pulmonary artery banding and related to variations in gene expression, highlighting the change from an alpha to a beta pattern from early to late follow-up times. 3) The study suggests that the left ventricle developed histological alterations accompanied by gene expression modifications simultaneously with the alterations found in the right ventricle.

Thalidomide modulates renal inflammation induced by brain death experimental model.

BACKGROUND: Brain death (BD) is characterized by a complex inflammatory response, resulting in dysfunction of potentially transplantable organs. This process is modulated by cytokines, which amplify graft immunogenicity. We have investigated the inflammatory response in an animal model of BD and analyzed the effects of thalidomide, a drug with powerful immunomodulatory properties. METHODS: BD was induced in male Lewis rats. We studied three groups: Control (sham-operated rats) (n = 6), BD (rats subjected to brain death) (n = 6) and BD + Thalid (BD rats treated with one dose of thalidomide (200 mg/Kg), administered by gavage) (n = 6). Six hours after BD, serum levels of urea and creatinine, as well as systemic and renal tissue protein levels of TNF-α and IL-6, were analyzed. We also determined the mRNA expression of ET-1, and macrophage infiltration by immunohistochemistry. RESULTS: BD induced a striking inflammatory status, demonstrated by a significant increase of plasma cytokines: TNF-α (2.8 ± 4.3 pg/mL [BD] vs. 9.4 ± 2.8 pg/mL [Control]), and IL-6 (6219.5 ± 1380.6 pg/mL [BD] vs. 1854.7 ± 822.6 pg/mL [Control]), and in the renal tissue: TNF-α (2.5 ± 0.3 relative expression [BD] vs. 1.0 ± 0.4 relative expression [Control]; p < 0.05), and IL-6 (4.0 ± 0.4 relative expression [BD] vs. 1.0 ± 0.3 relative expression [Control]; p < 0.05). Moreover, BD increased macrophages infiltration (2.47 ± 0.07 cells/field [BD] vs. 1.20 ± 0.05 cells/field [Control]; p < 0.05), and ET-1 gene expression (2.5 ± 0.3 relative expression [BD] vs. 1.0 ± 0.2 relative expression [Control]; p < 0.05). In addition, we have observed deterioration in renal function, characterized by an increase of urea (194.7 ± 25.0 mg/dL [BD] vs. 108.0 ± 14.2 mg/dL [Control]; p < 0.05) and creatinine (1.4 ± 0.04 mg/dL [BD] vs. 1.0 ± 0.07 mg/dL [Control]; p < 0.05) levels. Thalidomide administration significantly reduced plasma cytokines: TNF-α (5.1 ± 1.4 pg/mL [BD + Thalid] vs. BD; p < 0.05), and IL-6 (1056.5 ± 488.3 pg/mL [BD + Thalid] vs. BD; p < 0.05), as well as in the renal tissue: TNF-α (1.5 ± 0.2 relative expression [BD + Thalid] vs. BD; p < 0.05), and IL-6 (2.1 ± 0.3 relative expression [BD + Thalid] vs. BD; p < 0.05). Thalidomide treatment also induced a significant decrease in the expression of ET-1 (1.4 ± 0.3 relative expression [BD + Thalid] vs. BD; p < 0.05), and macrophages infiltration (1.17 ± 0.06 cells/field [BD + Thalid] vs. BD; p < 0.05). Also thalidomide prevented kidney function failure by reduced urea (148.3 ± 4.4 mg/dL [BD + Thalid] vs. BD; p < 0.05), and creatinine (1.1 ± 0.14 mg/dL [BD + Thalid] vs. BD; p < 0.05). CONCLUSIONS: The immunomodulatory properties of thalidomide were effective in decreasing systemic and local immunologic response, leading to diminished renal damage, as reflected in the decrease of urea and creatinine levels. These results suggest that use of thalidomide may represent a potential strategy for treating in BD kidney organ donors.

Photobiomodulation therapy's effects on cardiac fibrosis activation after experimental myocardial infarction.

INTRODUCTION: Ischemic heart disease is the leading cause of death worldwide, and interventions to reduce myocardial infarction (MI) complications are widely researched. Photobiomodulation therapy (PBMT) has altered multiple biological processes in tissues and organs, including the heart. OBJECTIVES: This study aimed to assess the temporal effects of PBMT on cardiac fibrosis activation after MI in rats. In this proof-of-concept study, we monitored the change in expression patterns over time of genes and microRNAs (miRNAs) involved in the formation of cardiac fibrosis post-MI submitted to PBMT. MATERIALS AND METHODS: Experimental MI was induced, and PBMT was applied shortly after coronary artery ligation (laser light of wavelength 660 nm, 15 mW of power, energy density 22.5 J/cm2 , 60 seconds of application, irradiated area 0.785 cm2 , fluence 1.1 J/cm2 ). Ventricular septal samples were collected at 30 minutes, 3, 6, 24 hours, and 3 days post-MI to determine temporal PBMT's effects on messenger RNA (mRNA) expression associated with cardiac fibrosis activation and miRNAs expression. RESULTS: PBMT, when applied after ischemia, reversed the changes in mRNA expression of myocardial extracellular matrix genes induced by MI. Surprisingly, PBMT modified cardiac miRNAs expression related to fibrosis replacement in the myocardium. Expression correlations between myocardial mRNAs were assessed. The correlation coefficient between miRNAs and target mRNAs was also determined. A positive correlation was detected among miR-21 and transforming growth factor beta-1 mRNA. The miR-29a expression negatively correlated to Col1a1, Col3a1, and MMP-2 mRNA expressions. In addition, we observed that miR-133 and Col1a1 mRNA were negatively correlated. CONCLUSION: The results suggest that PBMT, through the modulation of gene transcription and miRNA expressions, can interfere in cardiac fibrosis activation after MI, mainly reversing the signaling pathway of profibrotic genes.

Photobiomodulation Therapy on Myocardial Infarction in Rats: Transcriptional and Posttranscriptional Implications to Cardiac Remodeling.

BACKGROUND AND OBJECTIVES: Induction of myocardial infarction (MI) in rats by occlusion of the left anterior descending coronary artery is an experimental model used in research to elucidate functional, structural, and molecular modifications associated with ischemic heart disease. Photobiomodulation therapy (PBMT) has become a therapeutic alternative by modulating various biological processes eliciting several effects, including anti-inflammatory and pro-proliferative actions. The main objective of this work was to evaluate the effect of PBMT in the modulation of transcriptional and post-transcriptional changes that occurred in myocardium signal transduction pathways after MI. STUDY DESIGN/MATERIALS AND METHODS: Continuous wave (CW) non-thermal laser parameters were: 660 nm wavelength, power 15 mW, with a total energy of 0.9 J, fluence of 1.15 J/cm2 , spot size of 0.785 cm2 , and time of 60 seconds. Using in silico analysis, we selected and then, quantified the expression of messenger RNA (mRNA) of 47 genes of 9 signaling pathways associated with MI (angiogenesis, cell survival, hypertrophy, oxidative stress, apoptosis, extracellular matrix, calcium kinetics, cell metabolism, and inflammation). Messenger RNA expression quantification was performed in myocardial samples by polymerase chain reaction real-time array using TaqMan customized plates. RESULTS: Our results evidenced that MI modified mRNA expression of several well-known biomarkers related to detrimental cardiac activity in almost all signaling pathways analyzed. However, PBMT reverted most of these transcriptional changes. More expressively, PBMT provoked a robust decrease in mRNA expression of molecules that participate in post-MI inflammation and ECM composition, such as IL-6, TNF receptor, TGFb1, and collagen I and III. Global microRNA (miRNA) expression analysis revealed that PBMT decreased miR-221, miR-34c, and miR-93 expressions post-MI, which are related to deleterious effects in cardiac remodeling. CONCLUSION: Thus, the identification of transcriptional and post-transcriptional changes induced by PBMT may be used to interfere in the molecular dynamics of cardiac remodeling post-MI.

Increased Myocardial Retention of Mesenchymal Stem Cells Post-MI by Pre-Conditioning Exercise Training.

Stem cell (SC) therapy is a promising approach to improve post-myocardial infarction (MI) cardiac remodeling, but the proinflammatory microenvironment may lead to SC loss and, therefore, may have a negative impact on therapy. It appears that exercise training (ET) improves myocardial microenvironment for SC transplantation. Therefore, we tested the effect of ET on post-infarction retention of adipose-derived SCs (ADSCs) and its combined effects on the inflammatory microenvironment. Fischer-344 female rats were randomized to one of the following groups: Sham; sedentary coronary occlusion who did not receive ADSCs (sMI); sedentary coronary occlusion who received ADSCs; exercise coronary occlusion who received ADSCs. Rats were trained nine weeks prior to MI, followed by ADSCs transplantation. The MI led to left ventricle (LV) dilation and dysfunction, myocardial hypertrophy and fibrosis, and increased proinflammatory profile compared to Sham rats. Conversely, ADSCs transplanted rats exhibited, better morphological and functional LV parameters; inhibition of myocardial hypertrophy and fibrosis; and attenuation of proinflammatory cytokines (interleukins 1ß and 10, tumor necrosis factor α, and transforming growth factor ß) in the myocardium compared to sMI rats. Interestingly, ET enhanced the effect of ADSCs on interleukin 10 expression. There was a correlation between cytokine expression and myocardial ADSCs retention. The. ET enhanced the beneficial effects of ADSCs in infarcted myocardium, which was associated with higher ADSCs retention. These findings highlight the importance of ET in myocardial retention of ADSCs and attenuation of cardiac remodeling post-infarction. Cytokine analysis suggests improvement in ET-linked myocardial microenvironment based on its anti-inflammatory action.

Protective Role of UCP2 in Oxidative Stress and Apoptosis during the Silent Phase of an Experimental Model of Epilepsy Induced by Pilocarpine.

Neuroprotection is a desirable process in many neurological disorders, yet complex mechanisms involved in this field are not completely understood. The pilocarpine epilepsy model causes potent, seizure-induced excitotoxicity cell death and mitochondria impairment. The present study is aimed at investigating the role of UCP2, a ROS negative regulator, in the neuroprotection after cholinergic insult. Our data demonstrated that UCP2 expression was augmented in the rat hippocampus 3 days after status epilepticus (SE), reaching a peak on the fifth day, then returning to basal levels. Concomitantly, phospho-AKT expression levels were higher in the hippocampus during the early silent phase (5 days after SE). Additionally, it was demonstrated that the blockade of UCP2 by antisense oligonucleotides (ASO) in SE rats successfully diminished both UCP2 mRNA and protein contents. SE ASO rats presented increased mitochondrial proapoptotic factor expression, caspase-3 activity, inflammatory cytokine expression, and ROS formation. Moreover, ASO treatment diminished p-AKT expression and antioxidant enzyme activities after pilocarpine insult. In conclusion, the present results highlight the neuroprotective actions of UCP2, acting in the inhibition of apoptotic factors and oxidative stress, to increase neuron survival after SE onset.

Protective effects of photobiomodulation against resistance exercise-induced muscle damage and inflammation in rats.

We investigated whether low-level laser therapy (LLLT) prior to or post resistance exercise could attenuate muscle damage and inflammation. Female Wistar rats were assigned to non-LLLT or LLLT groups. An 830-nm DMC Laser Photon III was used to irradiate their hind legs with 2J, 4J, and 8J doses. Irradiations were performed prior to or post (4J) resistance exercise bouts. Resistance exercise consisted of four maximum load climbs. The load work during a resistance exercise bout was similar between Control (non-LLLT, 225 ± 10 g), 2J (215 ± 8 g), 4J (210 ± 9 g), and 8J (226 ± 9 g) groups. Prior LLLT did not induce climbing performance improvement, but exposure to 4J irradiation resulted in lower blood lactate levels post-exercise. The 4J dose decreased creatine kinase and lactic dehydrogenase levels post-exercise regardless of the time of application. Moreover, 4-J irradiation exposure significantly attenuated tumor necrosis factor alpha, interleukin-6, interleukin-1ß, cytokine-induced neutrophil chemoattractant-1, and monocyte chemoattractant protein-1. There was minor macrophage muscle infiltration in 4J-exposed rats. These data indicate that LLLT prior to or post resistance exercise can reduce muscle damage and inflammation, resulting in muscle recovery improvement. We attempted to determine an ideal LLLT dose for suitable results, wherein 4J irradiation exposure showed a significant protective role.

Can photobiomodulation associated with implantation of mesenchymal adipose-derived stem cells attenuate the expression of MMPs and decrease degradation of type II collagen in an experimental model of osteoarthritis?

This study aimed to determine whether photobiomodulation therapy (PBMT) could improve the bioavailability and chondroprotective benefits of mesenchymal stem cells injected into the knees of rats used as an experimental model of osteoarthritis (OA) as well as reduce the expression of matrix metalloproteinases (MMPs) and degradation of type II collagen (COL2-1) in the cartilage. Adipose-derived stem/stromal cells (ADSCs) were collected from three male Fischer 344 rats and characterized by flow cytometry. Fifty female Fischer 344 rats were distributed into five groups of 10 animals each. These groups were as follows: control, OA, OA PBMT, OA ADSC, and OA ADSC PBMT. OA was induced in the animals using a 4% papain solution. Animals from the OA ADSC and OA ADSC PBMT groups received an intra-articular injection of 10 × 106 ADSCs and were treated with PBMT by irradiation (wavelength: 808 nm, power: 50 mW, energy: 42 J, energy density: 71.2 J/cm2, spot size: 0.028). Euthanasia was performed 7 days after the first treatment. The use of PBMT alone and the injection of ADSCs resulted in downregulation of pro-inflammatory cytokines and MPs in cartilage compared to the OA group. PBMT and ADSCs caused upregulation of tissue inhibitors of MPs 1 and 2 and mRNA and protein expression of COL2-1 in cartilage compared to the OA group. The intra-articular injection of ADSCs and PBMT prevented joint degeneration resulting from COL2-1 degradation and modulated inflammation by downregulating cytokines and MMPs in the OA group.

Low-Level Laser Application in the Early Myocardial Infarction Stage Has No Beneficial Role in Heart Failure.

Low-level laser therapy (LLLT) has been targeted as a promising approach that can mitigate post-infarction cardiac remodeling. There is some interesting evidence showing that the beneficial role of the LLLT could persist long-term even after the end of the application, but it remains to be systematically evaluated. Therefore, the present study aimed to test the hypothesis that LLLT beneficial effects in the early post-infarction cardiac remodeling could remain in overt heart failure even with the disruption of irradiations. Female Wistar rats were subjected to the coronary occlusion to induce myocardial infarction or Sham operation. A single LLLT application was carried out after 60 s and 3 days post-coronary occlusion, respectively. Echocardiography was performed 3 days and at the end of the experiment (5 weeks) to evaluate cardiac function. After the last echocardiographic examination, LV hemodynamic evaluation was performed at baseline and on sudden afterload increases. Compared with the Sham group, infarcted rats showed increased systolic and diastolic internal diameter as well as a depressed shortening fraction of LV. The only benefit of the LLLT was a higher shortening fraction after 3 days of infarction. However, treated-LLLT rats show a lower shortening fraction in the 5th week of study when compared with Sham and non-irradiated rats. A worsening of cardiac function was confirmed in the hemodynamic analysis as evidenced by the higher LV end-diastolic pressure and lower +dP/dt and -dP/dt with five weeks of study. Cardiac functional reserve was also impaired by infarction as evidenced by an attenuated response of stroke work index and cardiac output to a sudden afterload stress, without LLLT repercussions. No significant differences were found in the myocardial expression of Akt1/VEGF pathway. Collectively, these findings illustrate that LLLT improves LV systolic function in the early post-infarction cardiac remodeling. However, this beneficial effect may be dependent on the maintenance of phototherapy. Long-term studies with LLLT application are needed to establish whether these effects ultimately translate into improved cardiac remodeling.

Photobiomodulation therapy in the modulation of inflammatory mediators and bradykinin receptors in an experimental model of acute osteoarthritis.

The objective of this study was to evaluate the effects of photobiomodulation therapy (PBMT) on inflammatory indicators, i.e., inflammatory mediators (TNF-α and CINC-1), and pain characterized by hyperalgesia and B1 and B2 receptor activation at 6, 24, and 48 h after papain-induced osteoarthritis (OA) in rats. Fifty-four rats were subjected to hyperalgesia evaluations and then divided randomly into three groups-a control group and two groups OA and OA PBMT group by using laser parameters at wavelength (808 nm), output power (50 mW), energy per point (4 Joules), power density (1.78 W/cm2), laser beam (0.028 cm2), and energy density (144 J/cm2)-the induction of osteoarthritis was then performed with 20-µl injections of a 4 % papain solution dissolved in 10 µl of saline solution, to which 10 µl of cysteine solution (0.03 M). The statistical analysis was performed using two-way ANOVA with Bonferroni's post hoc test for comparisons between the 6, 24, and 48 h and team points within each group, and between the control, injury, and PBMT groups, and p < 0.05 was considered to indicate a significant difference. The hyperalgesia was evaluated at 6, 24, and 48 h after the injury. PBMT at a wavelength of 808 nm and doses of 4 J, administered afterward, promotes increase at the threshold of pressure stimulus at 6, 24, and 48 h after application and promote cytokine attenuation levels (TNF and CINC-1) and bradykinin receptor (B1 and B2) along the experimental period. We conclude that photobiomodulation therapy was able to promote the reduction of proinflammatory cytokines such as TNF-α and CINC-1, to reduce the gene and protein expression of the bradykinin receptor (B1 and B2), as well as increasing the stimulus response threshold of pressure in an experimental model of acute osteoarthritis.

Exercise Training Attenuates Right Ventricular Remodeling in Rats with Pulmonary Arterial Stenosis.

Introduction: Pulmonary arterial stenosis (PAS) is a congenital defect that causes outflow tract obstruction of the right ventricle (RV). Currently, negative issues are reported in the PAS management: not all patients may be eligible to surgeries; there is often the need for another surgery during passage to adulthood; patients with mild stenosis may have later cardiac adverse repercussions. Thus, the search for approaches to counteract the long-term PAS effects showed to be a current target. At the study herein, we evaluated the cardioprotective role of exercise training in rats submitted to PAS for 9 weeks. Methods and Results: Exercise resulted in improved physical fitness and systolic RV function. Exercise also blunted concentric cavity changes, diastolic dysfunction, and fibrosis induced by PAS. Exercise additional benefits were also reported in a pro-survival signal, in which there were increased Akt1 activity and normalized myocardial apoptosis. These findings were accompanied by microRNA-1 downregulation and microRNA-21 upregulation. Moreover, exercise was associated with a higher myocardial abundance of the sarcomeric protein α-MHC and proteins that modulate calcium handling-ryanodine receptor and Serca 2, supporting the potential role of exercise in improving myocardial performance. Conclusion: Our results represent the first demonstration that exercise can attenuate the RV remodeling in an experimental PAS. The cardioprotective effects were associated with positive modulation of RV function, survival signaling pathway, apoptosis, and proteins involved in the regulation of myocardial contractility.

Comparative mRNA and MicroRNA Profiling during Acute Myocardial Infarction Induced by Coronary Occlusion and Ablation Radio-Frequency Currents.

The ligation of the left anterior descending coronary artery is the most commonly used experimental model to induce myocardial infarction (MI) in rodents. A high mortality in the acute phase and the heterogeneity of the size of the MI obtained are drawbacks recognized in this model. In an attempt to solve the problem, our group recently developed a new MI experimental model which is based on application of myocardial ablation radio-frequency currents (AB-RF) that yielded MI with homogeneous sizes and significantly reduce acute mortality. In addition, cardiac structural, and functional changes aroused by AB-RF were similar to those seen in animals with MI induced by coronary artery ligation. Herein, we compared mRNA expression of genes that govern post-MI milieu in occlusion and ablation models. We analyzed 48 mRNAs expressions of nine different signal transduction pathways (cell survival and metabolism signs, matrix extracellular, cell cycle, oxidative stress, apoptosis, calcium signaling, hypertrophy markers, angiogenesis, and inflammation) in rat left ventricle 1 week after MI generated by both coronary occlusion and AB-RF. Furthermore, high-throughput miRNA analysis was also assessed in both MI procedures. Interestingly, mRNA expression levels and miRNA expressions showed strong similarities between both models after MI, with few specificities in each model, activating similar signal transduction pathways. To our knowledge, this is the first comparison of genomic alterations of mRNA and miRNA contents after two different MI procedures and identifies key signaling regulators modulating the pathophysiology of these two models that might culminate in heart failure. Furthermore, these analyses may contribute with the current knowledge concerning transcriptional and post-transcriptional changes of AB-RF protocol, arising as an alternative and effective MI method that reproduces most changes seem in coronary occlusion.

Analgesic Effect of Photobiomodulation on Bothrops Moojeni Venom-Induced Hyperalgesia: A Mechanism Dependent on Neuronal Inhibition, Cytokines and Kinin Receptors Modulation.

BACKGROUND: Envenoming induced by Bothrops snakebites is characterized by drastic local tissue damage that involves an intense inflammatory reaction and local hyperalgesia which are not neutralized by conventional antivenom treatment. Herein, the effectiveness of photobiomodulation to reduce inflammatory hyperalgesia induced by Bothrops moojeni venom (Bmv), as well as the mechanisms involved was investigated. METHODOLOGY/PRINCIPAL FINDINGS: Bmv (1 µg) was injected through the intraplantar route in the right hind paw of mice. Mechanical hyperalgesia and allodynia were evaluated by von Frey filaments at different time points after venom injection. Low level laser therapy (LLLT) was applied at the site of Bmv injection at wavelength of red 685 nm with energy density of 2.2 J/cm2 at 30 min and 3 h after venom inoculation. Neuronal activation in the dorsal horn spinal cord was determined by immunohistochemistry of Fos protein and the mRNA expression of IL-6, TNF-α, IL-10, B1 and B2 kinin receptors were evaluated by Real time-PCR 6 h after venom injection. Photobiomodulation reversed Bmv-induced mechanical hyperalgesia and allodynia and decreased Fos expression, induced by Bmv as well as the mRNA levels of IL-6, TNF-α and B1 and B2 kinin receptors. Finally, an increase on IL-10, was observed following LLLT. CONCLUSION/SIGNIFICANCE: These data demonstrate that LLLT interferes with mechanisms involved in nociception and hyperalgesia and modulates Bmv-induced nociceptive signal. The use of photobiomodulation in reducing local pain induced by Bothropic venoms should be considered as a novel therapeutic tool for the treatment of local symptoms induced after bothropic snakebites.

Amelioration of cardiac function and activation of anti-inflammatory vasoactive peptides expression in the rat myocardium by low level laser therapy.

Low-level laser therapy (LLLT) has been used as an anti-inflammatory treatment in several disease conditions, even when inflammation is a secondary consequence, such as in myocardial infarction (MI). However, the mechanism by which LLLT is able to protect the remaining myocardium remains unclear. The present study tested the hypothesis that LLLT reduces inflammation after acute MI in female rats and ameliorates cardiac function. The potential participation of the Renin-Angiotensin System (RAS) and Kallikrein-Kinin System (KKS) vasoactive peptides was also evaluated. LLLT treatment effectively reduced MI size, attenuated the systolic dysfunction after MI, and decreased the myocardial mRNA expression of interleukin-1 beta and interleukin-6 in comparison to the non-irradiated rat tissue. In addition, LLLT treatment increased protein and mRNA levels of the Mas receptor, the mRNA expression of kinin B2 receptors and the circulating levels of plasma kallikrein compared to non-treated post-MI rats. On the other hand, the kinin B1 receptor mRNA expression decreased after LLLT. No significant changes were found in the expression of vascular endothelial growth factor (VEGF) in the myocardial remote area between laser-irradiated and non-irradiated post-MI rats. Capillaries density also remained similar between these two experimental groups. The mRNA expression of the inducible nitric oxide synthase (iNOS) was increased three days after MI, however, this effect was blunted by LLLT. Moreover, endothelial NOS mRNA content increased after LLLT. Plasma nitric oxide metabolites (NOx) concentration was increased three days after MI in non-treated rats and increased even further by LLLT treatment. Our data suggest that LLLT diminishes the acute inflammation in the myocardium, reduces infarct size and attenuates left ventricle dysfunction post-MI and increases vasoactive peptides expression and nitric oxide (NO) generation.

Estudo in vivo do manchamento dental causado pela ingestão de café associada ao clareamento profissional / In vivo study of dental discoloration caused by coffee ingestion associated within-office dental bleaching

Objective: The present study aims to verify the effectiveness of in-office dental bleaching using 35% hydrogen peroxide in patients with or without a habit of consuming coffee at least three times per day at different time intervals (pre-bleaching or baseline;48 hours post-bleaching or start; and 90 days post-bleaching or recall). Methods and Material - Forty patients with superior and inferior vital teeth from canine to canine participated in this study. The optical measurements with SpectroShade Microspectrophotometer (MHT, Verona, Italy) determined the pre-bleaching status (baselinemeasurement), the status at 48 hours post-bleaching (start measurement), and thestatus at 90 days post-bleaching (recall measurement). The Delta E (ΔE) value was determined, and the difference between the pre- and post-bleaching luminosity was used as an indicator of the degree of chromogenic alteration. The patients were divided into four groups according to the presence or absence of a coffee ingestion habit and according to different post-bleaching time intervals. These data were analyzed by ANOVA and in case of significant differences the mean values were compared usingthe Tukey test (p < 0.05). Results and Conclusions - In conclusion, it was possible to confirm that professional dental bleaching is an effective technique that can be usedboth in patients who drink and do not drink coffee. However, the maintainability of this treatment was significantly reduced in the group of patients who habitually drink coffee within a period of only 90 days

Objetivos: O presente estudo visa verificar a efetividade do clareamento dental profissional utilizando o peróxido de hidrogênio a 35% em pacientes com e sem o hábito de ingestão de café por pelo menos três vezes ao dia em diferentes intervalosde tempo (pré-clareamento ou baseline; 48 horas pós-clareamento ou start; e 90 diaspós-clareamento ou recall). Material e Métodos - Quarenta pacientes com dentes naturais inferiores e superiores participaram deste estudo. As tomadas de cor com o espectrofotômetro SpectroShade (MHT, Verona, Itália) determinaram a condição pré clareamento(medição baseline), a condição em 48 horas pós-clareamento (medição start),e a condição após 90 dias (medição recall). O valor de Delta E (ΔE) foi determinado, e a diferença entre a luminosidade na condição pré e pós-clareamentos foram utilizadas como o indicador do grau de alteração cromatogênica. Os pacientes foram divididos em quatro grupos de acordo com a presença ou ausência de hábitos de ingestão de café e dos diferentes períodos pós-clareamento. Os dados foram analisados via ANOVA e, quando necessário, os valores médios foram comparados utilizando o teste de Tukeya 5% de significância (p < 0.05). Resultados e Conclusões - Como conclusão foi possível confirmar que clareamento dental profissional é uma técnica efetiva e que pode ser utilizada tanto em pacientes que ingerem como nos que não ingerem café. Contudo, a durabilidade deste tratamento clareador é significativamente reduzida no grupo de pacientes que habitualmente bebem café dentro de um período relativamente curto, ou seja, de apenas 90 dias

Falha na implantação de um novo algoritmo de testes laboratoriais para o diagnóstico de infecção por HTLV-1 e HTLV-2 em população de risco / Lack in introducing a new algorithm of laboratorial tests for detecting HTLV-1 and HTLV-2 infections in at-risk population

Em vista dos problemas detectados no diagnóstico de infecção pelos vírus linfotrópicos de células T humanas dos tipos 1 e -2 (HTLV-1 e HTLV-2) em casuística encaminhada ao Instituto Adolfo Lutz de São Paulo, foi proposto um novo algoritmo de testes laboratoriais que utiliza duas amostras de sangue seqüenciais. Na primeira o sangue é coletado em tubo seco e feita triagem sorológica com dois ensaios imunoenzimáticos (EIAs). Na segunda, o sangue é coletado em tubo contendo o anticoagulante ácido etilenodiamino tetra acético (EDTA) para a repetição dos EIAs e para os testes confirmatórios de Western blot (WB) e reação em cadeia da polimerase (PCR). Os resultados obtidos com 313 amostras de sangue mostraram ineficiência do algoritmo, pois nos casos EIA reagentes, apenas 25% tiveram uma segunda amostra de sangue coletada e destas, apenas três em EDTA. Portanto, não foi possível comparar o desempenho da PCR em relação ao WB. Um algoritmo simples, de coleta única de sangue em tubo contendo EDTA foi proposto e vem sendo utilizado para a triagem e para os testes confirmatórios.