Photobiomodulation Improves the Inflammatory Response and Intracellular Signaling Proteins Linked to Vascular Function and Cell Survival in the Brain of Aged Rats.

Photobiomodulation is a non-pharmacological tool widely used to reduce inflammation in many tissues. However, little is known about its effects on the inflammatory response in the aged brain. We conducted the study to examine anti-inflammatory effects of photobiomodulation in aging brains. We used aged rats (20 months old) with control (handled, laser off) or transcranial laser (660 nm wavelength, 100 mW power) treatments for 10 consecutive days and evaluated the level of inflammatory cytokines and chemokines, and the expression and activation of intracellular signaling proteins in the cerebral cortex and the hippocampus. Inflammatory analysis showed that aged rats submitted to transcranial laser treatment had increased levels of IL-1alpha and decreased levels of IL-5 in the cerebral cortex. In the hippocampus, the laser treatment increased the levels of IL-1alpha and decreased levels of IL-5, IL-18, and fractalkine. Regarding the intracellular signaling proteins, a reduction in the ERK and p38 expression and an increase in the STAT3 and ERK activation were observed in the cerebral cortex of aged rats from the laser group. In addition, the laser treatment increased the hippocampal expression of p70S6K, STAT3, and p38 of aged rats. Taken together, our data indicate that transcranial photobiomodulation can improve the inflammatory response and the activation of intracellular signaling proteins linked to vascular function and cell survival in the aged brain.

Transcranial Laser Photobiomodulation Improves Intracellular Signaling Linked to Cell Survival, Memory and Glucose Metabolism in the Aged Brain: A Preliminary Study.

Aging is often accompanied by exacerbated activation of cell death-related signaling pathways and decreased energy metabolism. We hypothesized that transcranial near-infrared laser may increase intracellular signaling pathways beneficial to aging brains, such as those that regulate brain cell proliferation, apoptosis, and energy metabolism. To test this hypothesis, we investigated the expression and activation of intracellular signaling proteins in the cerebral cortex and hippocampus of aged rats (20 months old) treated with the transcranial near-infrared laser for 58 consecutive days. As compared to sham controls, transcranial laser treatment increased intracellular signaling proteins related to cell proliferation and cell survival, such as signal transducer and activator of transcription 3 (STAT3), extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), p70 ribosomal protein S6 kinase (p70S6K) and protein kinase B (PKB), also known as Akt that is linked to glucose metabolism. In addition, ERK is linked to memory, while ERK and JNK signaling pathways regulate glucose metabolism. Specifically, the laser treatment caused the activation of STAT3, ERK, and JNK signaling proteins in the cerebral cortex. In the hippocampus, the laser treatment increased the expression of p70S6K and STAT3 and the activation of Akt. Taken together, the data support the hypothesis that transcranial laser photobiomodulation improves intracellular signaling pathways linked to cell survival, memory, and glucose metabolism in the brain of aged rats.

Avaliação molecular e imuno-histoquímica de malformações linfáticas orais / Molecular and immunohistochemistry evaluation of oral lymphatic malformations

As malformações linfáticas são distúrbios do desenvolvimento caracterizados pelo crescimento excessivo de vasos linfáticos. Essa condição acontece principalmente em região de cabeça e pescoço devido à presença fisiológica de grande concentração de vasos linfáticos na região. As malformações linfáticas podem ocorrer de maneira isolada ou associadas a síndromes como de CLOVES e Klippel-Trènaunay. A presença de mutações no gene PIK3CA e a ativação das vias PI3K/AKT e MAPK/ERK pode ocorrer tanto nas malformações linfáticas esporádicas, como naquelas associadas a síndromes. As mutações em PIK3CA ocorrem nos éxons 10 e 20, sendo as mutações no códon 1047 (éxon 20) as mais frequente nas malformações linfáticas esporádicas. No entanto, em malformações linfáticas orais não se sabe se estes fenômenos ocorrem. O objetivo deste estudo foi avaliar a presença de mutações no códon 1047 do gene PIK3CA e avaliar a ativação das vias PI3K/AKT e MAPK/ERK em amostras de malformações linfáticas orais. Uma amostra de conveniência de 14 tecidos de malformações linfáticas orais fixados em formol e embebidos em parafina foram submetidas a reações de imuno-histoquímica para as formas fosforiladas de AKT1 (pAKT-Ser473) e ERK1/2 (pERK1/2-Thr202/Tyr204), marcadores de ativação das vias PI3K/AKT e MAPK/ERK, respectivamente. Quatro destas amostras foram submetidas a Sequenciamento de Sanger para o códon 1047 do gene PIK3CA. Foram observados padrões de marcação positivas para pAKT1 e pERK1/2 nas células endoteliais de todas as amostras de malformações linfáticas orais avaliadas. Todas as amostras submetidas ao Sequenciamento de Sanger apresentaram sequência selvagem para a região de interesse. Com os resultados obtidos sugere-se que as vias PI3K/AKT e MAPK/ERK estão envolvidas na patogênese das malformações linfáticas orais.

Lymphatic malformations are developmental disorders characterized by excessive growth of lymphatic vessels. This condition occurs mainly in the head and neck region due to the physiological presence of high concentration of lymphatic vessels in the region. Lymphatic malformations may occur in isolation or associated with syndromes such as CLOVES and Klippel-Trènaunay. Mutations in the PIK3CA gene and activation of the PI3K/AKT and MAPK/ERK pathways may occur both in sporadic lymphatic malformations and in those associated with syndromes. Mutations in hotspot 1047 are the most frequently found in isolated lymphatic malformation. However, in oral lymphatic malformations it is not known whether these mutations occur. The aim of this study was to evaluate the presence of mutations in codon 1047 of the PIK3CA gene and to evaluate the activation of PI3K/AKT and MAPK/ERK pathways in samples of oral lymphatic malformations. A convenience sample of 14 tissues of oral lymphatic malformations formalin fixed paraffin embedded were submitted to immunohistochemistry reactions to the phosphorylated forms of AKT1 (pAKT-Ser473) and ERK1/2 (pERK1/2-Thr202/Tyr204), activation markers of PI3K/AKT and MAPK/ERK pathways, respectively. Four of these samples were submitted to Sanger Sequencing for codon 1047 of the PIK3CA gene. Positive marking patterns for pAKT1 and pERK1/2 were observed in the endothelial cells of all samples of oral lymphatic malformations evaluated. All samples submitted to Sanger Sequencing were wild type for the region of interest. With the results obtained it is suggested that the PI3K/AKT and MAPK/ERK pathways are involved in the pathogenesis of oral lymphatic malformations.

Actualización en plasma rico en plaquetas / Platelet rich plasma update

Resumen El plasma rico en plaquetas es un producto derivado de la sangre, rico en péptidos y proteínas de señalización intercelular, así como citoquinas capaces de intervenir en cada una de las etapas de la regeneración de varios tejidos. Principalmente, se le han atribuido efectos antiinflamatorios en diferentes lesiones, así como otros efectos biológicos sobre las células y tejidos. A la fecha, no existe un protocolo estándar de producción o preparación, tampoco se ha descrito una dosis específica; la forma de aplicación es muy variable y depende de la condición por tratar. A pesar de ello, se han visto efectos positivos en campos como: odontología, ortopedia, dermatología, medicina reconstructiva, oftalmología, medicina deportiva, medicina vascular, entre otros. Su regulación es muy diversa a nivel internacional. Aunque hay expectativas con el tratamiento de plasma rico en plaquetas, no hay suficientes ensayos clínicos robustos que brinden un alto nivel de evidencia para validarlo como un tratamiento de rutina frente a determinada condición clínica. Además, no se pueden comparar fácilmente los resultados de diferentes investigaciones, por la variabilidad en el método de preparación y por la falta de homogeneidad en las lesiones tratadas, entre otros factores. Es por lo anterior que resulta necesario desarrollar más investigaciones serias que conlleven al establecimiento de un protocolo estandarizado, así como demostrar la efectividad de este nuevo tratamiento, de forma que se culmine con la implementación de nuevas terapias validadas y autorizadas para garantizar una mejoría real a los pacientes.

Abstract Platelet-rich plasma is a blood-derived product, rich in peptides and intercellular signaling proteins and cytokines capable of intervening in each stage of the regeneration of various tissues. Mainly, it has been attributed anti-inflammatory effects in different lesions, as well as other biological effects on cells and tissues. To date, there is no standard production or preparation protocol, nor has a specific dose been described. The form of application is very variable and depends on the condition to be treated. Despite this, positive effects have been seen in different fields such as: dentistry, orthopedics, dermatology, reconstructive medicine, ophthalmology, sports medicine, vascular medicine among others. Its regulation is very diverse internationally. Although there is a lot of expectation with the treatment of platelet-rich plasma, there are not enough robust clinical trials that provide a high level of evidence to validate it as a routine treatment for a certain clinical condition. In addition, the results of different investigations cannot be easily compared due to the variability in the method of preparation and the lack of homogeneity in the treated lesions, among other factors. It is for this reason that it is necessary to develop more serious investigations that lead to the establishment of a standardized protocol, as well as to demonstrate the effectiveness of this new treatment and culminate with the implementation of new validated and authorized therapies to guarantee a real improvement to the patients.

Snapshots of the Signaling Complex DesK:DesR in Different Functional States Using Rational Mutagenesis and X-ray Crystallography.

We have developed protocols to generate site-specific variants of the histidine-kinase DesK and its cognate response regulator DesR, conducive to trapping different signaling states of the proteins. Co-expression of both partners in E. coli, ensuring an excess of the regulator, was essential for soluble production of the DesK:DesR complexes and further purification. The 3D structures of the complex trapped in the phosphotransferase and in the phosphatase reaction steps, were solved by X-ray crystallography using molecular replacement. The solution was not trivial, and we found that in silico-generated models used as search probes, were instrumental to succeeding in placing a large portion of the complex in the asymmetric unit. Electron density maps were then clear enough to allow for manual model building attaining complete atomic models. These methods contribute to tackling a major challenge in the bacterial signaling field, namely obtaining stable kinase:regulator complexes, in distinct conformational states, amenable for high-resolution crystallographic studies.

Suppressor of cytokine signaling 1 expression during LPS-induced inflammation and bone loss in rats

Abstract This study aimed to characterize the dynamics of suppressor of cytokine signaling (SOCS1) expression in a rat model of lipopolysaccharide-induced periodontitis. Wistar rats in the experimental groups were injected three times/week with LPS from Escherichia coli on the palatal aspect of the first molars, and control animals were injected with vehicle (phosphate-buffered saline). Animals were sacrificed 7, 15, and 30 days after the first injection to analyze inflammation (stereometric analysis), bone loss (macroscopic analysis), gene expression (qRT-PCR), and protein expression/activation (Western blotting). The severity of inflammation and bone loss associated with LPS-induced periodontitis increased from day 7 to day 15, and it was sustained through day 30. Significant (p < 0.05) increases in SOCS1, RANKL, OPG, and IFN-γ gene expression were observed in the experimental group versus the control group at day 15. SOCS1 protein expression and STAT1 and NF-κB activation were increased throughout the 30-day experimental period. Gingival tissues affected by experimental periodontitis express SOCS1, indicating that this protein may potentially downregulate signaling events involved in inflammatory reactions and bone loss and thus may play a relevant role in the development and progression of periodontal disease.

DNA methylation analysis of SOCS1, SOCS3, and LINE-1 in microdissected gingival tissue.

OBJECTIVES: DNA methylation plays a critical role in the regulation of the transcription of the suppressors of cytokine signaling (SOCS) 1 and SOCS3, which are modulators in the inflammation. We hypothesized that the methylation status of SOCS1, SOCS3, and long interspersed nuclear element (LINE)-1 in gingival tissues previously inflamed would be similar to that found in gingival tissues without clinical inflammation in the period studied. MATERIALS AND METHODS: Laser capture microdissection was performed to isolate epithelial and connective gingival tissues. The groups were comprised by ten patients without history of periodontitis and absence of clinical signs of inflammation in the gingiva during the study (healthy group) and ten patients with history of periodontitis, presenting inflammation in the gingival tissue at the first examination of the study (controlled chronic periodontitis group). The gingival biopsies from the controlled chronic periodontitis group were collected after controlling the inflammation. DNA methylation patterns were analyzed using methylation-specific high-resolution melting and combined bisulfite restriction analysis. RESULTS: DNA methylation levels for SOCS1 and SOCS3 did not differ between groups or tissues; likewise, no differences were observed in total LINE-1 methylation or at specific loci. CONCLUSION: At 3 months following control of inflammation in gingival tissues, the methylation profile of SOCS1, SOCS3, and LINE-1 is similar between connective and epithelial tissues from patients that were previously affected or not by chronic inflammation. CLINICAL RELEVANCE: Clinical results of a successful treatment are observed after inflammation control and the molecular findings illustrate local and general methylation patterns in recovering tissues toward health conditions and might help to understand events that are occurring in oral cells.

Avaliação de polimorfismos genéticos como biomarcadores na evolução da cardiomiopatia chagásica / Evaluation of genetic polymorphisms as biomarkers in the evolution of Chagas cardiomyopathy

O Trypanosoma cruzi é um parasita intracelular e agente causador da doença de Chagas, que afeta milhões de pessoas em todo o mundo. Sabe-se que durante os processos de inflamação, regeneração e fibrose desencadeados pelo T. cruzi no hospedeiro há a participação de diversos mediadores e fatores. O objetivo deste trabalho foi avaliar a associação entre polimorfismos de nucleotídeos únicos com as formas clínicas e o grau de fibrose em pacientes com doença de Chagas. Os polimorfismos foram analisados por PCR em tempo real. Foram incluídos no estudo 55 pacientes com diagnóstico de doença de Chagas e classificados de acordo com a forma clínica da doença, sendo que 17 apresentavam a forma indeterminada, 15 a forma cardíaca sem disfunção ventricular e 23 a forma cardíaca com disfunção ventricular. Os genótipos CA dos polimorfismos do gene LGALS3 (rs4644 e rs4652); AG e GG do SOCS3 (rs4969170); CT e TT do IL-28B (rs12979860 e 8099917, respectivamente); AG, AG, CC, AG e AG do CLDN-1 (rs10212165, rs3909582, rs9865082, rs9880018 e rs9848283, respectivamente); e CC do CCL5 (rs2280789) foram estatisticamente mais frequentes em pacientes com a forma cardíaca do que com a forma indeterminada da doença. Com relação ao grau de fibrose, os genótipos CC dos polimorfismos do gene LGALS3 (rs4644 e rs4652); AA do SOCS3 (rs4969170); CC do rs12979860 e TT do rs8099917 do IL-28B; AA do rs10212165, AA, AG e GG do rs3909582, CC e CT do rs9865082, AG e GG do rs9880018 e AA do rs9848283 do gene CLDN1; e CC do CCL5 (rs2280789) foram estatisticamente mais frequentes em indivíduos com fibrose cardíaca <15% quando comparados com o grupo com fibrose ≥15%. Diante do exposto concluimos que os polimorfismos analisados podem ser úteis como futuros biomarcadores para estadiamento e conduta terapêutica em pacientes com doença de Chagas.

Trypanosoma cruzi is an intracellular parasite and the agent that causes Chagas disease, which affects millions of people worldwide. Several factors and mediators are known to actively participate in the inflammation, fibrosis and tissue regeneration, which is triggered by T. cruzi within the host. The aim of this study was to evaluate the association of single nucleotide polymorphisms with clinical forms and rate of fibrosis in Chagas disease patients. The polymorphisms were analyzed by real-time PCR. The study consisted of 55 Chagas disease patients that were classified according to the clinical form of the disease, including 17 patients presenting the indeterminate form, 15 patients presenting the cardiac form without ventricular dysfunction and 23 patients presenting the cardiac form with ventricular dysfunction. The genotypes of CA of LGALS3 gene polymorphisms (rs4644 and rs4652); AG and GG of SOCS3 (rs4969170); CT and TT of IL-28B (rs12979860 and 8099917, respectively); AG, AG, CC, AG and AG of CLDN-1 (rs10212165, rs3909582, rs9865082, rs9880018 and rs9848283, respectively); and CC of CCL5 (rs2280789) were significantly more frequent in patients presenting the cardiac form compared to patients presenting the indeterminate form. Regarding the degree of fibrosis, the CC genotype of polymorphisms of the genes LGALS3 (rs4644 and rs4652); AA of SOCS3 (rs4969170); CC of rs12979860 and TT of rs8099917 of the IL-28B; AA of rs10212165 and AA, AG and GG of rs3909582, CC and CT of rs9865082, AG and GG of rs9880018 and AA of rs9848283 of the gene CLDN1; and CC of CCL5 (rs2280789) were statistically more frequent in patients presenting <15% cardiac fibrosis when compared to patients presenting fibrosis ≥15%. Taken together, our results suggest that the polymorphisms analyzed may be useful biomarkers for therapeutic management of patients with Chagas disease.