Effect of cytoglobin overexpression on extracellular matrix component synthesis in human tenon fibroblasts

BACKGROUND: Conjunctival filtering bleb scar formation is the main reason for the failure of glaucoma filtration surgery. Cytoglobin (Cygb) has been reported to play an important role in extracellular matrix (ECM) remodeling, fibrosis and tissue damage repairing. This study aimed to investigate the role of Cygb in anti-scarring during excessive conjunctival wound healing after glaucoma filtration surgery. METHODS: Cygb was overexpressed in human tenon fibroblasts (hTFs) by transfecting hTFs with lentiviral particles encoding pLenti6.2-FLAG-Cygb. Changes in the mRNA and protein levels of fibronectin, collagen I, collagen III, TGF-ß1, and HIF1α were determined by RT-PCR and western blotting respectively. RESULTS: After Cygb overexpression, hTFs displayed no significant changes in visual appearance and cell counts compared to controls. Whereas, Cygb overexpression significantly decreased the mRNA and protein expression levels of collagen I, collagen III and fibronectin compared with control (p < 0.01). There was also a statistically significant decrease in the mRNA and protein levels of TGF-ß1 and HIF-1α in hTFs with overexpressed Cygb compared with control group (p < 0.05). CONCLUSION: Our study provided evidence that overexpression of Cygb decreased the expression levels of fibronectin, collagen I, collagen III, TGF-ß1 and HIF-1α in hTFs. Therefore, therapies targeting Cygb expression in hTFs may pave a new way for clinicians to solve the problem of post-glaucoma surgery scarring.

Healing effect of andiroba-based emulsion in cutaneous wound healing via modulation of inflammation and transforming growth factor beta 3

Abstract Purpose: To evaluate the effects and mechanisms of andiroba-based emulsion (ABE) topical treatment on full-thickness cutaneous wounds in rats. Methods: The wounds were harvested on days 3, 7, 15, and 20 post-surgery. Wound contraction rate, quantitative immunohistochemistry [macrophages, myofibroblasts, capillaries, collagens (col) I and III, transforming growth factor β3β (TGFβ3)], and tensile strength were assessed. Results: Treated wounds were smaller, contracted earlier and had increased angiogenesis, fewer CD68+ and M2 macrophages on days 7 and 15, but higher on day 20. Myofibroblasts appeared on days 3 to 7 in untreated wounds and on days 7 to 15 in treated wounds. TGFβ3 levels were higher in the treated wounds, less dense collagen fibers, lower col I/III ratios and a higher tensile strength. Conclusion: These results demonstrate the important anti-inflammatory role of treatment and the associated modulation of macrophages, myofibroblasts, and TGFβ3 levels. Collagen fibers in the treated wounds were more organized and less dense, similar to unwounded skin, which likely contributed to the higher tensile strength.

Immunohistochemical expression of TGF-ß1 and osteonectin in engineered and Ca(OH)2-repaired human pulp tissues

Abstract The aim of the present study was to evaluate the expression of transforming growth factor-β1 (TGF-β1) and osteonectin (ON) in pulp-like tissues developed by tissue engineering and to compare it with the expression of these proteins in pulps treated with Ca(OH)2 therapy. Tooth slices were obtained from non-carious human third molars under sterile procedures. The residual periodontal and pulp soft tissues were removed. Empty pulp spaces of the tooth slice were filled with sodium chloride particles (250-425 µm). PLLA solubilized in 5% chloroform was applied over the salt particles. The tooth slice/scaffold (TS/S) set was stored overnight and then rinsed thoroughly to wash out the salt. Scaffolds were previously sterilized with ethanol (100-70°) and washed with phosphate-buffered saline (PBS). TS/S was treated with 10% EDTA and seeded with dental pulp stem cells (DPSC). Then, TS/S was implanted into the dorsum of immunodeficient mice for 28 days. Human third molars previously treated with Ca(OH)2 for 90 days were also evaluated. Samples were prepared and submitted to histological and immunohistochemical (with anti-TGF-β1, 1:100 and anti-ON, 1:350) analyses. After 28 days, TS/S showed morphological characteristics similar to those observed in dental pulp treated with Ca(OH)2. Ca(OH)2-treated pulps showed the usual repaired pulp characteristics. In TS/S, newly formed tissues and pre-dentin was colored, which elucidated the expression of TGF-β1 and ON. Immunohistochemistry staining of Ca(OH)2-treated pulps showed the same expression patterns. The extracellular matrix displayed a fibrillar pattern under both conditions. Regenerative events in the pulp seem to follow a similar pattern of TGF-β1 and ON expression as the repair processes.

Effect of EDTA on TGF-ß1 released from the dentin matrix and its influence on dental pulp stem cell migration

Abstract: Bioactive molecules stored in dentin, such as transforming growth factor beta1 (TGF-b1), may be involved in the signaling events related to dental tissue repair. The authors conducted an in vitro evaluation of the amount of TGF-b1 released from dentin slices after treatment with 10% ethylenediaminetetraacetic acid (EDTA), 2.5% sodium hypochlorite (NaOCl) or phosphate-buffered saline (PBS), and the effect of this growth factor on stem cell migration from human exfoliated deciduous teeth (SHED). Sixty 1-mm-thick tooth slices were prepared with or without the predentin layer, and treated with either 10% EDTA for 1 minute, 2.5% NaOCl for 5 days or kept in PBS. Tooth slice conditioned media were prepared and used for TGF-b1 ELISA and migration assays. Culture medium with different concentrations of recombinant human TGF-b1 (0.5, 1.0, 5.0 or 10.0 ng/mL) was also tested by migration assay. The data were evaluated by ANOVA and Tukey's test. Optical density values corresponding to media conditioned by tooth slices either containing or not containing the predentin layer and treated with 10% EDTA were statistically greater than the other groups and close to 1 ng/mL. Increased rates of migration toward media conditioned by tooth slices containing the predentin layer and treated with PBS, 10% EDTA or 2.5% NaOCl were observed. Recombinant human TGF-b1 also stimulated migration of SHED, irrespective of the concentration used. EDTA may be considered an effective extractant of TGF-b1 from the dentin matrix. However, it does not impact SHED migration, suggesting that other components may account for the cell migration.

Protective effects of tumor necrosis factor-α blockade by adalimumab on articular cartilage and subchondral bone in a rat model of osteoarthritis

We aimed to investigate the effects of an anti-tumor necrosis factor-α antibody (ATNF) on cartilage and subchondral bone in a rat model of osteoarthritis. Twenty-four rats were randomly divided into three groups: sham-operated group (n=8); anterior cruciate ligament transection (ACLT)+normal saline (NS) group (n=8); and ACLT+ATNF group (n=8). The rats in the ACLT+ATNF group received subcutaneous injections of ATNF (20 μg/kg) for 12 weeks, while those in the ACLT+NS group received NS at the same dose for 12 weeks. All rats were euthanized at 12 weeks after surgery and specimens from the affected knees were harvested. Hematoxylin and eosin staining, Masson's trichrome staining, and Mankin score assessment were carried out to evaluate the cartilage status and cartilage matrix degradation. Matrix metalloproteinase (MMP)-13 immunohistochemistry was performed to assess the cartilage molecular metabolism. Bone histomorphometry was used to observe the subchondral trabecular microstructure. Compared with the rats in the ACLT+NS group, histological and Mankin score analyses showed that ATNF treatment reduced the severity of the cartilage lesions and led to a lower Mankin score. Immunohistochemical and histomorphometric analyses revealed that ATNF treatment reduced the ACLT-induced destruction of the subchondral trabecular microstructure, and decreased MMP-13 expression. ATNF treatment may delay degradation of the extracellular matrix via a decrease in MMP-13 expression. ATNF treatment probably protects articular cartilage by improving the structure of the subchondral bone and reducing the degradation of the cartilage matrix.

Influence of different body positions in vital capacity in patients on postoperative upper abdominal / Influência de diferentes posições corporais na capacidade vital em pacientes no pós-operatório abdominal superior / Influencia de diferentes posiciones corporales en la capacidad vital en pacientes en el postoperatorio abdominal superior

RATIONALE: The changes in body position can cause changes in lung function, and it is necessary to understand them, especially in the postoperative upper abdominal surgery, since these patients are susceptible to postoperative pulmonary complications. OBJECTIVE: To assess the vital capacity in the supine position (head at 0° and 45°), sitting and standing positions in patients in the postoperative upper abdominal surgery. METHODS: A cross-sectional study conducted between August 2008 and January 2009 in a hospital in Salvador/BA. The instrument used to measure vital capacity was analogic spirometer, the choice of the sequence of positions followed a random order obtained from the draw of the four positions. Secondary data were collected from the medical records of each patient. RESULTS: The sample consisted of 30 subjects with a mean age of 45.2 ± 11.2 years, BMI 20.2 ± 1.0 kg/m2. The position on orthostasis showed higher values of vital capacity regarding standing (mean change: 0.15 ± 0.03 L; p = 0.001), the supine to 45 (average difference: 0.32 ± 0.04 L; p = 0.001) and 0° (0.50 ± 0.05 L; p = 0.001). There was a positive trend between the values of forced vital capacity supine to upright posture (1.68 ± 0.47; 1.86 ± 0.48; 2.02 ± 0.48 and 2.18 ± 0.52 L; respectively). CONCLUSION: Body position affects the values of vital capacity in patients in the postoperative upper abdominal surgery, increasing in postures where the chest is vertical. .

JUSTIFICATIVA: As alterações no posicionamento corporal podem ocasionar mudanças na função respiratória e é necessário compreendê-las, principalmente no pós-operatório abdominal superior, já que os pacientes estão suscetíveis a complicações pulmonares pós-operatórias. OBJETIVO: Verificar a capacidade vital nas posições de decúbito dorsal (cabeceira a 0° e 45°), sentado e em ortostase em pacientes no pós-operatório de cirurgia abdominal superior. MÉTODOS: Estudo transversal, feito entre agosto de 2008 e janeiro de 2009, em um hospital na cidade de Salvador (BA). O instrumento usado para mensuração da capacidade vital (CV) foi o ventilômetro analógico e a escolha da sequência das posições seguiu uma ordem aleatória obtida a partir de sorteio das quatro posições. Os dados secundários foram colhidos nos prontuários de cada paciente. RESULTADOS: A amostra foi composta por 30 indivíduos com idade média de 45,2 ± 11,2 anos e IMC 20,2 ± 1,0 kg/m2. A posição em ortostase apresentou valores maiores da CV em relação à sedestração (média das diferenças: 0,15 ± 0,03 litros; p = 0,001), ao decúbito dorsal a 45° (média das diferenças: 0,32 ± 0,04 litros; p = 0,001) e 0° (0,50 ± 0,05 litros; p = 0,001). Houve um aumento positivo entre os valores de CVF do decúbito dorsal para a postura ortostática (1,68 ± 0,47; 1,86 ± 0,48; 2,02 ± 0,48 e 2,18 ± 0,52 litros; respectivamente). CONCLUSÃO: A posição do corpo afeta os valores da CV em pacientes no pós-operatório de cirurgia abdominal superior, com aumento nas posturas em que o tórax encontra-se verticalizado. .

JUSTIFICACIÓN: Las alteraciones en el posicionamiento corporal pueden ocasionar cambios en la función respiratoria y es necesario comprenderlas, principalmente en el postoperatorio abdominal superior, ya que los pacientes son susceptibles a complicaciones pulmonares postoperatorias. OBJETIVO: Verificar la capacidad vital en las posiciones de decúbito dorsal (cabeza a 0° y 45°), sentado y en ortostasis en pacientes en el postoperatorio de cirugía abdominal superior. MÉTODOS: Estudio transversal realizado entre agosto de 2008 y enero de 2009, en un hospital en la ciudad de Salvador (BA). El instrumento usado para la medición de la capacidad vital (CV) fue el espirómetro analógico y la elección de la secuencia de las posiciones siguió un orden aleatorio que se obtuvo a partir de un sorteo de las 4 posiciones. Los datos secundarios fueron extraídos de las historias clínicas de cada paciente. RESULTADOS: La muestra se compuso de 30 individuos con edades medias de 45,2 ± 11,2 años e IMC de 20,2 ± 1 kg/m2. La posición en ortostasis presentó valores mayores de CV con relación a la posición sedente (media de las diferencias: 0,15 ± 0,03 L; p = 0,001), al decúbito dorsal a 45° (media de las diferencias: 0,32 ± 0,04 L; p = 0,001) y a 0° (0,50 ± 0,05 L; p = 0,001). Hubo un aumento positivo entre los valores de CV forzada del decúbito dorsal para la postura ortostática (1,68 ± 0,47; 1,86 ± 0,48; 2,02 ± 0,48 y 2,18 ± 0,52 L, respectivamente). CONCLUSIÓN: La posición del cuerpo afecta los valores de la CV en pacientes durante el postoperatorio de cirugía abdominal superior, con aumento en las posturas en las que el tórax está verticalizado. .

Episiotomy healing assessment: Redness, Oedema, Ecchymosis, Discharge, Approximation (REEDA) scale reliability / Avaliação da cicatrização da episiotomia: confiabilidade da escala REEDA (Redness, Oedema, Ecchymosis, Discharge, Approximation) / Evaluación de la curación de episiotomía: confiabilidad de la escala de Enrojecimiento, Edema, Equimosis, Drenaje, Aproximación (REEDA)

OBJECTIVE: to analyse the Redness, Oedema, Ecchymosis, Discharge, Approximation (REEDA) scale reliability when evaluating perineal healing after a normal delivery with a right mediolateral episiotomy. METHOD: observational study based on data from a clinical trial conducted with 54 randomly selected women, who had their perineal healing assessed at four time points, from 6 hours to 10 days after delivery, by nurses trained in the use of this scale. The kappa coefficient was used in the reliability analysis of the REEDA scale. RESULTS: the results indicate good agreement in the evaluation of the discharge item (0.75< Kappa ≥0.88), marginal and good agreement in the first three assessments of oedema (0.16< Kappa ≥0.46), marginal agreement in the evaluation of ecchymosis (0.25< Kappa ≥0.42) and good agreement regarding redness (0.46< Kappa ≥0.66). For the item coaptation, the agreement decreased from excellent in the first assessment to good in the last assessment. In the fourth evaluation, the assessment of all items displayed excellent or good agreement among the evaluators. CONCLUSION: the difference in the scores among the evaluators when applying the scale indicates that this tool must be improved to allow an accurate assessment of the episiotomy healing process. .

OBJETIVO: analisar a confiabilidade da escala REEDA (Redness, Oedema, Ecchymosis, Discharge, Approximation) para avaliar a cicatrização do períneo após parto vaginal com episiotomia médio-lateral direita. MÉTODO: estudo observacional, baseado em dados coletados em ensaio clínico, conduzido com 54 mulheres, selecionadas aleatoriamente. As mesmas tiveram o processo de cicatrização perineal avaliado em quatro momentos (de 6 horas a 10 dias após o parto), por enfermeiras treinadas para o uso da escala. O coeficiente kappa foi usado para análise de confiabilidade da escala REEDA. RESULTADOS: os resultados indicam bom nível de concordância na avaliação do item secreção (0,75< Kappa ≥0,88), concordância boa e marginal em relação ao item equimose (0,25< Kappa ≥0,42), e bom nível de concordância em relação à hiperemia (0,46< Kappa ≥0,66). O nível de concordância referente à avaliação do item coaptação diminuiu de excelente, na primeira avaliação, para bom, na última avaliação. CONCLUSÃO: a diferença entre as pontuações atribuídas pelas avaliadoras na aplicação da escala indica que o instrumento precisa ser melhorado, para permitir avaliações mais precisas do processo de cicatrização da episiotomia. .

OBJETIVO: analizar la confiabilidad de la escala de Enrojecimiento, Edema, Equimosis, Drenaje, Aproximación (REEDA) en la evaluación de la curación perineal tras parto normal con episiotomía mediolateral derecha. MÉTODO: estudio observacional con base en datos de un ensayo clínico conducido con 54 mujeres elegidas de forma aleatoria, con evaluación de su curación perineal en cuatro momentos, entre 6 horas y 10 días después del parto, por enfermeras capacitadas en el uso de esta escala. El coeficiente de kappa fue utilizado en el análisis de confiabilidad de la escala REEDA. RESULTADOS: los resultados indican buena concordancia en la evaluación del ítem drenaje (0,75< Kappa ≥0,88), concordancia marginal y buena en las primeras tres evaluaciones de edema (0,16< Kappa ≥0,46), concordancia marginal en la evaluación de equimosis (0,25< Kappa ≥0,42) y buena concordancia sobre enrojecimiento (0,46< Kappa ≥0,66). Para el ítem coaptación, la concordancia disminuyó de excelente en la primera evaluación hasta buena en la última. En el cuarto momento, la evaluación de todos los ítems mostró concordancia excelente o buena entre los evaluadores. CONCLUSIÓN: la diferencia en las notas entre los evaluadores en la aplicación de la escala indica que esta herramienta debe ser mejorada para permitir una evaluación correcta del proceso de curación de la episiotomía. .

Fluoride modulates preosteoblasts viability and matrix metalloproteinases-2 and -9 activities

This study evaluated the influence of fluoride on cell viability and activity of matrix metalloproteinases (MMP) -2 and -9 secreted by preosteoblasts. Preosteoblasts (MC3T3-E1 murine cell line) were cultured in MEM medium supplement with 10% Fetal Bovine Serum (FBS) and nucleosides/ribonucleosides without ascorbic acid. Adherent cells were treated with different concentrations of F (as sodium fluoride-NaF) in medium (5 x 10-6 M, 10-5 M, 10-4 M and 10-3 M) for 24, 48, 72 and 96 h at 37ºC, 5% CO2. Control cells were cultivated in MEM only. After each period, preosteoblast viability was assessed by MTT assay. MMP-2 and -9 activities were performed by gel zymography. Also, alkaline phosphatase (ALP) activity was quantified by colorimetry in all experimental groups. It was shown that cultured cells with the highest dose of F (10-3 M) for 96 h decreased preosteoblast viability while lower doses of F did not alter it, when compared to untreated cells. No differences were observed in ALP activity among groups. Moreover, compared to control, the treatment of cells with F at low dose slightly increased MMP-2 and -9 activities after 24 h. It was concluded that F modulates preosteoblast viability in a dose-dependent manner and also may regulate extracellular matrix remodeling.

Neste estudo, buscou-se avaliar a influência do fluoreto (F) na viabilidade celular e atividade das metaloproteinases de matriz (MMP) -2 e -9 secretado pelos pré-osteoblastos. Pré-osteoblastos (linhagem celular MC3T3-E1 murina) foram cultivados em meio MEM suplementado com 10% de soro fetal bovino (FBS) e nucleosídeos/ribonucleosídeos sem ácido ascórbico. Células aderidas foram tratadas com diferentes concentrações de F (na forma de fluoreto de sódio-NaF) em meio (5 x 10-6 M, 10-5 M, 10-4 M e 10-3 M) por 24, 48, 72 e 96 h a 37ºC, 5 % de CO2. Células do grupo controle foram cultivadas apenas em MEM. Após cada período, a viabilidade dos pré-osteoblastos foi avaliada por MTT. A atividade das MMP-2 e -9 foram analisadas pela zimografia. Além disso, a atividade da fosfatase alcalina (FA) foi quantificada por colorimetria em todos os grupos experimentais. Foi demonstrado que as células cultivadas com a maior dose de F (10-3 M) no período de 96 h tiveram sua viabilidade comprometida, enquanto doses mais baixas de F não a alteraram significativamente, quando comparado com células não tratadas. Não foi observada diferença na atividade da FA entre os grupos. Além disso, o tratamento de células com F em baixas doses, comparado ao grupo controle, promoveu um pequeno aumento da atividade das MMP-2 e -9 após 24 h. Pode-se concluir que o F modula a viabilidade de pré-osteoblastos de uma maneira dose-dependente e também pode regular a remodelação da matriz extracelular.

Efeito da criopreservação e/ou da descelularização na matriz extracelular de condutos valvados porcinos / Effects of cryopreservation and/or decellularization on extracellular matrix of porcine valves

O objetivo desse estudo foi avaliar a morfologia de valvas pulmonares porcinas criopreservadas e/ou descelularizadas para determinar uma solução que remova as células, sem promover danos à matriz extracelular. Valvas pulmonares porcinas foram incubadas por 24h em soluções de deoxicolato de sódio 1% e de dodecil sulfato de sódio 0,1% e 0,3%, com ou sem criopreservação adicional. A avaliação foi feita com microscopia óptica (hematoxilina eosina, orceína acética ou Gomori) e por morfometria. A efetividade das soluções foi variável, mas os melhores resultados foram obtidos com enxertos frescos descelularizados com dodecil sulfato de sódio 0,1%.

The objective of this study was to evaluate the morphology of decelluarized and/or cryopreserved porcine pulmonary valves, to determine a solution capable of completely remove the cells without damaging the extracellular matrix. Porcine pulmonary valves were incubated for 24 hs in sodium deoxicholate 1% or sodium dodecyl sulfate 0.1 and 0.3%, with or without associated cryopreservation. Evaluation was done with optical microscopy (Hematoxilin-Eosin, Acetic Orcein and Gomori) and with morphometric analysis. The effectiviness of the solutions was variable, but the best results were obtained with the sodium dodecyl sulfate solution 0.1%.

Inactivation of capsaicin-sensitive nerves reduces pulmonary remodeling in guinea pigs with chronic allergic pulmonary inflammation

Pulmonary remodeling is an important feature of asthma physiopathology that can contribute to irreversible changes in lung function. Although neurokinins influence lung inflammation, their exact role in the extracellular matrix (ECM) remodeling remains to be determined. Our objective was to investigate whether inactivation of capsaicin-sensitive nerves modulates pulmonary ECM remodeling in animals with chronic lung inflammation. After 14 days of capsaicin (50 mg/kg, sc) or vehicle administration, male Hartley guinea pigs weighing 250-300 g were submitted to seven inhalations of increasing doses of ovalbumin (1, 2.5, and 5 mg/mL) or saline for 4 weeks. Seventy-two hours after the seventh inhalation, animals were anesthetized and mechanically ventilated and the lung mechanics and collagen and elastic fiber content in the airways, vessels and lung parenchyma were evaluated. Ovalbumin-exposed animals presented increasing collagen and elastic fiber content, respectively, in the airways (9.2 ± 0.9; 13.8 ± 1.2), vessels (19.8 ± 0.8; 13.4 ± 0.5) and lung parenchyma (9.2 ± 0.9; 13.8 ± 1.2) compared to control (P < 0.05). Capsaicin treatment reduced collagen and elastic fibers, respectively, in airways (1.7 ± 1.1; 7.9 ± 1.5), vessels (2.8 ± 1.1; 4.4 ± 1.1) and lung tissue (2.8 ± 1.1; 4.4 ± 1.1) of ovalbumin-exposed animals (P < 0.05). These findings were positively correlated with lung mechanical responses to antigenic challenge (P < 0.05). In conclusion, inactivation of capsaicin-sensitive nerve fibers reduces pulmonary remodeling, particularly collagen and elastic fibers, which contributes to the attenuation of pulmonary functional parameters.

Effect of puerarin on the expression of extracellular matrix in rats with streptozotocin-induced diabetic nephropathy.

Background. Inhibition of the formation of advanced glycation end-products delays the development of diabetic nephropathy. Puerarin decreases the formation of these products. We studied the effect of puerarin in a rat model of diabetic nephropathy. Methods. Three groups of rats were studied: a control group, a diabetic group in whom diabetic nephropathy was induced by intraperitoneal injection of streptozotocin, and a puerarin group in which diabetic rats were treated with puerarin. During and after treatment, measurements were made on the rats’ general status, blood glucose level, blood urea nitrogen, serum creatinine, creatinine clearance rate and urinary albumin excretion over 24 hours. The expression of collagen I and heparan sulphate proteoglycan in the extracellular matrix of the glomerulus was assessed by immunohistochemistry. Results. Rats in the puerarin group had a better general condition than those with diabetes. They also had lower blood urea nitrogen, serum creatinine and urinary albumin excretion rate over 24 hours compared with those in the diabetic group. The creatinine clearance and expression of heparan sulphate proteoglycan in the kidney also increased significantly in the puerarin group compared with that in the diabetic group. Conclusion. Puerarin seems to have certain protective effects on diabetic nephropathy induced by streptozotocin. This is caused possibly by regulating the expression of glomerular extracellular matrix.

Effect of photodynamic therapy on the extracellular matrix and associated components

In many countries, photodynamic therapy (PDT) has been recognized as a standard treatment for malignant conditions (for example, esophageal and lung cancers) and non-malignant ones such as age-related macular degeneration and actinic keratoses. The administration of a non-toxic photosensitizer, its selective retention in highly proliferating cells and the later activation of this molecule by light to form reactive oxygen species that cause cell death is the principle of PDT. Three important mechanisms are responsible for the PDT effectiveness: a) direct tumor cell kill; b) damage of the tumor vasculature; c) post-treatment immunological response associated with the leukocyte stimulation and release of many inflammatory mediators like cytokines, growth factors, components of the complement system, acute phase proteins, and other immunoregulators. Due to the potential applications of this therapy, many studies have been reported regarding the effect of the treatment on cell survival/death, cell proliferation, matrix assembly, proteases and inhibitors, among others. Studies have demonstrated that PDT alters the extracellular matrix profoundly. For example, PDT induces collagen matrix changes, including cross-linking. The extracellular matrix is vital for tissue organization in multicellular organisms. In cooperation with growth factors and cytokines, it provides cells with key signals in a variety of physiological and pathological processes, for example, adhesion/migration and cell proliferation/differentiation/death. Thus, the focus of the present paper is related to the effects of PDT observed on the extracellular matrix and on the molecules associated with it, such as, adhesion molecules, matrix metalloproteinases, growth factors, and immunological mediators.

Bases moleculares da glomerulopatia diabética / Molecular bases of diabetic nephropathy

O principal determinante da nefropatia diabética é a hiperglicemia, mas hipertensão e fatores genéticos também estão envolvidos. O glomérulo é o foco de lesão, onde proliferação celular mesangial e produção excessiva de matriz extracelular decorrem do aumento da glicose intracelular, por excesso de glicose extracelular e hiperexpressão de GLUT1. Seguem-se aumento do fluxo pela via dos polióis, estresse oxidativo intracelular, produção intracelular aumentada de produtos avançados da glicação não enzimática (AGEs), ativação da via da PKC, aumento da atividade da via das hexosaminas e ativação de TGF-beta1. Altas concentrações de glicose também aumentam angiotensina II (AII) nas células mesangiais por aumento intracelular da atividade da renina (ações intrácrinas, mediando efeitos proliferativos e inflamatórios diretamente). Portanto, glicose e AII exercem efeitos proliferativos celulares e de matriz extracelular nas células mesangiais, utilizando vias de transdução de sinais semelhantes, que levam a aumento de TGF-beta1. Nesse estudo são revisadas as vias que sinalizam os efeitos da glicose e AII nas células mesangiais em causar os eventos-chaves relacionados à gênese da glomerulopatia diabética. As alterações das vias de sinalização implicadas na glomerulopatia, aqui revisadas, suportam dados de estudos observacionais/ensaios clínicos, onde controle metabólico e anti-hipertensivo, especificamente com inibidores do sistema renina-angiotensina, têm-se mostrado importantes - e aditivos - na prevenção do início e progressão da nefropatia. Novas estratégias terapêuticas dirigidas aos eventos intracelulares descritos deverão futuramente promover benefício adicional.

The determinant of the diabetic nephropathy is hyperglycemia, but hypertension and other genetic factors are also involved. Glomerulus is the focus of the injury, where mesangial cell proliferation and extracellular matrix occur because of the increase of the intra- and extracellular glucose concentration and overexpression of GLUT1. Sequentially, there are increases in the flow by the poliol pathway, oxidative stress, increased intracellular production of advanced glycation end products (AGEs), activation of the PKC pathway, increase of the activity of the hexosamine pathway, and activation of TGF-beta1. High glucose concentrations also increase angiotensin II (AII) levels. Therefore, glucose and AII exert similar effects in inducing extracellular matrix formation in the mesangial cells, using similar transductional signal, which increases TGF-beta1 levels. In this review we focus in the effect of glucose and AII in the mesangial cells in causing the events related to the genesis of diabetic nephropathy. The alterations in the signal pathways discussed in this review give support to the observational studies and clinical assays, where metabolic and antihypertensive controls obtained with angiotensin-converting inhibitors have shown important and additive effect in the prevention of the beginning and progression of diabetic nephropathy. New therapeutic strategies directed to the described intracellular events may give future additional benefits.

Proteoglycans production by aortic vascular smooth muscle cells from hypertensive rats

Remodeling of large and small arteries contributes to the development and complications of hypertension. Artery structural changes in chronic sustained hypertension include vascular smooth muscle cells (VSMC) proliferation and extracellular matrix (ECM) modifications. Extracellular constituents such as proteoglycans (PGs), may modulate vascular stiffness and VSMC growth and differentiation. We examined the effect of growth factors on secreted and membrane-bound PGs synthesis by cultured aortic smooth muscle cells (SMC) from 12- to 14- week-old spontaneously hypertensive rats (SHR) and age-matched Wistar rats. After stimulation with platelet-derived growth factor (PDGF-BB), 10% fetal calf serum (FCS) or 0.1% FCS as control, PGs synthesis (dpm/ng DNA) was evaluated in the medium (M-ECM) and in the cell layer (P-ECM) by a double-isotopic label method using both [3H]-glucosamine and [35S]-sodium sulfate which are incorporated into all complex carbohydrates or only into sulfated dysaccharides, respectively. Data are presented as percent of the control (0.1% FCS). SHR VSMC displayed a significantly greater synthesis of M-ECM [3H]-PGs than Wistar rat cells, with both treatments, but no differences in M-ECM [35S] uptake were found in any case. In the P-ECM, both PDGF-BB and 10% FCS produced a greater effect on [3H]-PGs and sulfated PGs synthesis in VSMC from SHR. An important change seen in SHR cells was a significant decreased sulfation, assessed by [35S]/[3H] ratio, in basal and stimulation conditions. Present results indicate the existence of changes in PGS synthesis and modulation in VSMC from a conduit-artery of SHR and support the pathophysiological role proposed for matrix proteoglycans in the vascular wall changes associated to hypertension and related vascular diseases as atherosclerosis.

In vitro anti-proliferation/cytotoxic activity of cantharidin (Spanish Fly) and related derivatives

The anti-cancer therapeutic promise of cantharidin is limited because of its high mammalian toxicity. In order to find new anti-cancer lead compounds with reduced toxicity of the cantharidin prototype, the following seven derivatives were screened against the human SH-SY5Y neuroblastoma and MCF-7 breast cancer cells in vitro: 2,3-dimethyl-7-oxabicylo-[2.2.1]heptane-2,3-dicarboxylic anhydride (cantharidin) [1], 1-cyclohexen-1,2-dicarboxylic anhydride [2], cis-4-cyclohexen-1,2-dicarboxylic anhydride [3], cis-1, 2-cyclohexanedicarboxylic anhydride [4], exo-7-oxabicyclo[2.2.1]hept-5-ene-2-3 dicarboxylic anhydride [5], exo-7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin) [6], and (S)-(-)-O-acetylmalic anhydride [7]. Cantharidin, was found to be the most effective anti-proliferative compound on both cell lines. However, on the human neuroblastoma cells cantharidin was of equal toxicity to compound [6]. Mode of action studies revealed that cantharidin inhibited growth factor-mediated activation of mitogen activated protein kinase (MAPkinase) and attenuated the de-phosphorylation of the extracellular regulated kinases 1 and 2 (erk1 and erk2)

Quantitave and qualitative interferences of pentoxifillyne on hepatic Schistosoma mansoni granulomas: effects on extracellular matrix and eosinophil population

Mast cells and eosinophils actively participate in tissue repair and are prominent components of Schistosoma mansoni granulomas. Since pentoxifillyne (PTX) is an immunomodulatory and antifibrotic substance, we aimed to characterize, by morphological techniques, the effect of this drug on fibrosis developed inside murine hepatic schistosomal granulomatous reaction, beyond the quantification of eosinophil and mast cell populations. The drug (1 mg/100 g animal weight) was administrated from 35 to 90 days post-infection, when the animals were killed. The intragranulomatous interstitial collagen network was analyzed by confocal laser scanning microscopy, the number of eosinophils and mast cells was quantified and the results were validated by t-student test. Treatment did not interfere on the granuloma evolution but caused a significant decrease in the total and involutive number of hepatic granulomas (p = 0.01 and 0.001, respectivelly), and in the intragranulomatous accumulation of eosinophils (p = 0.0001). Otherwise, the number of mast cells was not significantly altered (p = 0.9); however, it was positively correlated with the number of granulomatous structures (r = 0.955). In conclusion, PTX does not affect development and collagen deposition in S. mansoni murine granuloma, but decreases the intragranulomatous eosinophil accumulation possibly due to its immunomodulatory capability, interfering in cellular recruitment and/or differentiation

Extracellular matrix molecules as targets for brown spider venom toxins

Loxoscelism, the term used to describe lesions and clinical manifestations induced by brown spider's venom (Loxosceles genus), has attracted much attention over the last years. Brown spider bites have been reported to cause a local and acute inflammatory reaction that may evolve to dermonecrosis (a hallmark of envenomation) and hemorrhage at the bite site, besides systemic manifestations such as thrombocytopenia, disseminated intravascular coagulation, hemolysis, and renal failure. The molecular mechanisms by which Loxosceles venoms induce injury are currently under investigation. In this review, we focused on the latest reports describing the biological and physiopathological aspects of loxoscelism, with reference mainly to the proteases recently described as metalloproteases and serine proteases, as well as on the proteolytic effects triggered by L. intermedia venom upon extracellular matrix constituents such as fibronectin, fibrinogen, entactin and heparan sulfate proteoglycan, besides the disruptive activity of the venom on Engelbreth-Holm-Swarm basement membranes. Degradation of these extracellular matrix molecules and the observed disruption of basement membranes could be related to deleterious activities of the venom such as loss of vessel and glomerular integrity and spreading of the venom toxins to underlying tissues

Influencia del 4-metil umbelliferil ß-D-xilosido sobre la matriz extracelular durante el desarrollo de la aorta en embriones de pollo / Influence of the 4-metyl umbelliferil ß-D-xilosido on the extracelullar during the develoment of the aortic in chick embryos

Se realizó un estudio ultraesructural e histoquímico del efecto que ejerce el 4-metil umbelliferil ß-D-xilósido (4MUX) sobre la pared de la aorta de embriones de pollo del estadío 36. Se inocularon huevos fértiles de gallina white legorn a los 2.5 días de desarrollo (estadío 17) con 0.1 ml de 4MUX. Sus efectos se observaron con técnicas de microscopía electrónica de barrido e histoquímicas. Se ha puesto de manifiesto que el 4MUX interfiere en el desarrollo normal de la aorta. Causando alteraciones en la distribución de elastina, colágeno y GAGs en los espacios intercelulares