The m-rna, expression of serca2 and ncx1 in the process of pharmacological cell protection in experimental acute pancreatitis induced by taurocholate / Expressão do rna-m, da serca2 e do ncx1 no processo de proteção celular farmacológica na pancreatite aguda experimental induzida por taurocolato

ABSTRACT Background: Intracellular calcium overload is known to be a precipitating factor of pancreatic cell injury in acute pancreatitis (AP). Intracellular calcium homeostasis depends of Plasmatic Membrane Calcium ATPase (PMCA), Sarcoplasmic Endothelial Reticulum Calcium ATPase 2 (SERCA 2) and the Sodium Calcium Exchanger (NCX1). The antioxidant melatonin (Mel) and Trisulfate Disaccharide (TD) that accelerates NCX1 action could reduce the cell damage determined by the AP. Aim: To evaluate m-RNA expressions of SERCA2 and NCX1 in acute pancreatitis induced by sodium taurocholate in Wistar rats pre-treated with melatonin and/or TD. Methods: Wistar rats were divided in groups: 1) without AP; 2) AP without pre-treatment; 3) AP and Melatonin; 4) AP and TD; 5) AP and Melatonin associated to TD. Pancreatic tissue samples were collected for detection of SERCA2 and NCX1 m-R NA levels by polymerase chain reaction (PCR). Results: Increased m-RNA expression of SERCA2 in the melatonin treated group, without increase of m-RNA expression of the NCX1. The TD did not affect levels of SERCA2 and NCX1 m-RNA expressions. The combined melatonin and TD treatment reduced the m-RNA expression of SERCA2. Conclusions: The effect of melatonin is restricted to increased m-RNA expression of SERCA2. Although TD does not affect gene expression, its action in accelerating calcium exchanger function can explain the slightest expression of SERCA2 m-RNA when associated with Melatonin, perhaps by a joint action of drugs with different and but possibly complementary mechanisms.

RESUMO Racional: A lesão celular da pancreatite aguda (PA) envolve sobrecarga de cálcio, regulada pela atividade da Cálcio ATPase de membrana (PMCA), Cálcio ATPase do Retículo (SERCA2) e pelo Trocador Sódio Cálcio (NCX1). A melatonina (antioxidante) e o Dissacarídeo Trissulfatado (acelerador do NCX1) poderiam reduzir a lesão celular na PA. Objetivo: Avaliar a expressão do RNAm da SERCA2 e NCX1 em modelo animal de pancreatite aguda tratados com melatonina e/ou dissacarídeo trissulfatado (DT). Método: Ratos Wistar foram divididos em grupos: 1) sem pancreatite aguda; 2) com pancreatite aguda por taurocolato; 3) PA e Melatonina; 4) PA e DT; 5) PA e Melatonina com DT. Amostras de tecido foram colhidas para detecção dos níveis de RNAm da SERCA2 e NCX1 por PCR. Resultados: Houve aumento da expressão do RNAm da SERCA2 no grupo com PA tratados com Melatonina, porém sem aumento de expressão do NCX1. O DT não afetou os níveis de SERCA2 e NCX1. O tratamento conjunto com Melatonina e DT diminuiu a expressão da SERCA2. Conclusões: O efeito da Melatonina é restrito ao aumento da expressão da SERCA2. O DT não tem ação na expressão gênica, porém sua ação na aceleração do trocador na retirada do cálcio pode explicar a menor expressão da SERCA2 quando associado à Melatonina, pela ação conjunta de drogas com mecanismos diferentes e possivelmente complementares.

Evaluation of the metabolism of glycosaminoglycans in patients with interstitial cystis

Introduction: Painful bladder syndrome/interstitial cystitis (PBS/IC) pathogenesis is not fully known, but evidence shows that glycosaminoglycans (GAG) of bladder urothelium can participate in its genesis. The loss of these compounds facilitates the contact of urine compounds with deeper portions of bladder wall triggering an inflammatory process. We investigated GAG in urine and tissue of PBS/IC and pure stress urinary incontinence (SUI) patients to better understand its metabolism. Materials and Methods: Tissue and urine of 11 patients with PBS/IC according to NIDDK criteria were compared to 11 SUI patients. Tissue samples were analyzed by histological, immunohistochemistry and immunofluorescence methods. Statistical analysis were performed using t Student test and Anova, considering significant when p < 0.05. Results: PBS/IC patients had lower concentration of GAG in urine when compared to SUI (respectively 0.45 ± 0.11 x 0.62 ± 0.13 mg/mg creatinine, p < 0.05). However, there was no reduction of the content of GAG in the urothelium of both groups. Immunofluorescence showed that PBS/IC patients had a stronger staining of TGF-beta, decorin (a proteoglycan of chondroitin/dermatan sulfate), fibronectin and hyaluronic acid. Conclusion: the results suggest that GAG may be related to the ongoing process of inflammation and remodeling of the dysfunctional urothelium that is present in the PBS/IC. .

Influência do envelhecimento na concentração de ácido hialurônico nas pregas vocais de ratas fêmeas / Influence of aging on hyaluronic acid concentration in the vocal folds of female rats

A vibração das pregas vocais é um importante fator envolvido na produção vocal e o envelhecimento pode alterar a quantidade de ácido hialurônico da prega vocal levando a disfonia. OBJETIVO: Este estudo compara a concentração de ácido hialurônico nas pregas vocais de ratas fêmeas idosas e jovens. Desenho do estudo: estudo experimental. MATERIAL E MÉTODO: Foram utilizadas pregas vocais de 13 ratas fêmeas divididas em dois grupos: cinco ratas idosas e oito ratas jovens. A concentração tecidual do ácido hialurônico foi determinada por meio de método fluorimétrico utilizando a proteína de ligação ao ácido hialurônico imobilizada em placas de enzyme-linked immunosorbent assay (ELISA) e também conjugada à biotina. Estreptavidina marcada com európio foi adicionada e, depois de európio ter sido liberado com o uso de solução de enhancement; a fluorescência final foi medida em um fluorímetro. RESULTADOS: Foram encontradas as seguintes concentrações de ácido hialurônico nas pregas vocais de acordo com os grupos: 581,7 ng/mg em ratas idosas e 1275,6 ng/mg em ratas jovens. A análise estatística mostrou diferença entre os grupos. CONCLUSÃO: A prega vocal de ratas idosas tem uma menor concentração de ácido hialurônico do que a concentração da prega vocal de ratas jovens.

The vibration of the vocal fold lamina propria is an important factor involved in vocal production and aging may change the amount of hyaluronic acid in the vocal fold leading to dysphonia. AIMS: This study compares the concentration of hyaluronic acid in vocal folds of aged and young female rats. Study design: experimental. MATERIALS AND METHODS: We used the vocal cords of 13 female rats divided into two groups: five aged rats and eight young ones. The tissue concentration of hyaluronic acid was determined using the fluorimetric method with the hyaluronic acid binding-protein coated on plates of enzyme-linked immunosorbent assay (ELISA), conjugated with biotin. Europium-labeled streptavidin was added and, after europium release with the use of enhancement solution, the final fluorescence was measured in a fluorometer. RESULTS: We found the following concentrations of hyaluronic acid in vocal fold according to the group: 581.7 ng/mg in old female rats and 1275.6 ng/mg in young female rats. Statistical analysis showed differences between groups. CONCLUSIONS: The vocal folds of old female rats have a lower concentration of hyaluronic acid when compared to such concentration on the vocal folds of young female rats.

Heparan sulfate proteoglycans: structure, protein interactions and cell signaling

Heparan sulfate proteoglycans are ubiquitously found at the cell surface and extracellular matrix in all the animal species. This review will focus on the structural characteristics of the heparan sulfate proteoglycans related to protein interactions leading to cell signaling. The heparan sulfate chains due to their vast structural diversity are able to bind and interact with a wide variety of proteins, such as growth factors, chemokines, morphogens, extracellular matrix components, enzymes, among others. There is a specificity directing the interactions of heparan sulfates and target proteins, regarding both the fine structure of the polysaccharide chain as well precise protein motifs. Heparan sulfates play a role in cellular signaling either as receptor or co-receptor for different ligands, and the activation of downstream pathways is related to phosphorylation of different cytosolic proteins either directly or involving cytoskeleton interactions leading to gene regulation. The role of the heparan sulfate proteoglycans in cellular signaling and endocytic uptake pathways is also discussed.

Proteoglicanos de heparam sulfato são encontrados tanto superfície celular quanto na matriz extracelular em todas as espécies animais. Esta revisão tem enfoque nas características estruturais dos proteoglicanos de heparam sulfato e nas interações destes proteoglicanos com proteínas que levam à sinalização celular. As cadeias de heparam sulfato, devido a sua variedade estrutural, são capazes de se ligar e interagir com ampla gama de proteínas, como fatores de crescimento, quimiocinas, morfógenos, componentes da matriz extracelular, enzimas, entreoutros. Existe uma especificidade estrutural que direciona as interações dos heparam sulfatos e proteínas alvo. Esta especificidade está relacionada com a estrutura da cadeia do polissacarídeo e os motivos conservados da cadeia polipeptídica das proteínas envolvidas nesta interação. Os heparam sulfatos possuem papel na sinalização celular como receptores ou coreceptores para diferentes ligantes. Esta ligação dispara vias de sinalização celular levam à fosforilação de diversas proteínas citosólicas ou com ou sem interações diretas com o citoesqueleto, culminando na regulação gênica. O papel dos proteoglicanos de heparam sulfato na sinalização celular e vias de captação endocítica também são discutidas nesta revisão.

Urinary glycosaminoglycans excretion and the effect of dimethyl sulfoxide in an experimental model of non-bacterial cystitis

PURPOSE: We reproduced a non-bacterial experimental model to assess bladder inflammation and urinary glycosaminoglycans (GAG) excretion and examined the effect of dimethyl sulfoxide (DMSO). MATERIALS AND METHODS: Female rats were instilled with either protamine sulfate (PS groups) or sterile saline (control groups). At different days after the procedure, 24 h urine and bladder samples were obtained. Urinary levels of hyaluronic acid (HA) and sulfated glycosaminoglycans (S-GAG) were determined. Also to evaluate the effect of DMSO animals were instilled with either 50 percent DMSO or saline 6 hours after PS instillation. To evaluate the effect of DMSO in healthy bladders, rats were instilled with 50 percent DMSO and controls with saline. RESULTS: In the PS groups, bladder inflammation was observed, with polymorphonuclear cells during the first days and lymphomononuclear in the last days. HA and S-GAG had 2 peaks of urinary excretion, at the 1st and 7th day after PS injection. DMSO significantly reduced bladder inflammation. In contrast, in healthy bladders, DMSO produced mild inflammation and an increase in urinary HA levels after 1 and 7 days and an increase of S-GAG level in 7 days. Animals instilled with PS and treated with DMSO had significantly reduced levels of urinary HA only at the 1st day. Urinary S-GAG/Cr levels were similar in all groups. CONCLUSIONS: Increased urinary levels of GAG were associated with bladder inflammation in a PS-induced cystitis model. DMSO significantly reduced the inflammatory process after urothelial injury. Conversely, this drug provoked mild inflammation in normal mucosa. DMSO treatment was shown to influence urinary HA excretion.

Heparina de alto peso molecular. Uma alternativa nas operaçöes com circulaçäo extracorpórea: estudo experimental / High molecular weight heparin. An alternative in extracorporeal circulation surgery: an experimental study

Introduçäo: As síndromes hemorrágicas no intra e pós-operatório de operaçöes com circulaçäo extracorpórea (CEC) constituem motivo de preocupaçäo e, parte delas, pode ser atribuída à heparina näo fracionada (HNF), droga indispensável e, até hoje, insubstituível nesse tipo de procedimento. Alguns autores consideram a açäo anticoagulante da HNF como o principal responsável pelo sangramento e investem em drogas antifibrinolíticas ou que alteram a atividade plaquetária para tentar substituí-la. Toda HNF contém fraçöes de heparina de baixo peso molecular (HBPM), näo neutralizáveis pela protamina, que, em doses elevadas, e/ou em pacientes heparino-sensíveis, podem causar vasoplegia e aumento no sangramento pós-operatório em operaçöes com CEC. Material e Métodos: Isolamos uma heparina de alto peso molecular (HAPM - peso modal de 25.000 Daltons), com 11 por cento de fraçöes de HBPM (< 7.000 Daltons), para experiências "in vitro" e "in vivo", e comparamos com HNF (peso modal de 15.000 Daltons), com 21 por cento de fraçöes de HBPM. Resultados: A atividade específica anticoagulante, por massa, foi superior quando comparada com a HNF tanto "in vitro", 273 ui/mg contra 181 ui/mg e TTPA mais elevado nas várias diluiçöes, como "in vivo", em cäes, durante CEC, comprovado pelo TCA, TTPA e heparinemia. A vida média da HNF foi de 60 minutos e acima de 90 minutos para a HAPM, na situaçäo de experimentaçäo. Conclusäo: Acreditamos que esta experiência, inédita na literatura indexada, nos habilite ao uso da HAPM, em seres humanos, para averiguaçäo da sua melhor neutralizaçäo pela protamina e menor incidência de hemorragia

Clinical and laboratorial study of 19 cases of mucopolysaccharidoses

The mucopolysaccharidoses (MPS) are a heterogeneous group of inborn errors of lysosomal glycosaminoglycan (GAG) metabolism. The importance of this group of disorders among the inborn errors of metabolism led us to report 19 cases. METHOD: We performed clinical, radiological, and biochemical evaluations of the suspected patients, which allowed us to establish a definite diagnosis in 19 cases. RESULTS: Not all patients showed increased GAG levels in urine; enzyme assays should be performed in all cases with strong clinical suspicion. The diagnosis was made on average at the age of 48 months, and the 19 MPS cases, after a full clinical, radiological, and biochemical study, were classified as follows: Hurler -- MPS I (1 case); Hunter -- MPS II (2 cases); Sanfilippo -- MPS III (2 cases); Morquio -- MPS IV (4 cases); Maroteaux-Lamy -- MPS VI (9 cases); and Sly -- MPS VII (1 case). DISCUSSION: The high relative frequency of Maroteaux-Lamy disease contrasts with most reports in the literature and could express a population variability

Anticoagulant, antithrombotic and antihemostatic activities of heparin: structural requeriments, mechanism of action and clinical applications

The structural features for the anticoagulant, antithrombotic and antihemostatic activities of the heparin molecule as well as the resulting clinical applications are reviewed. For anticlotting activity, an intact heparin molecule with a minimum molecular weight of 8 kDa is necessary. On the other hand, for the antithrombotic activity, a heparin hexasaccharide fragment already exhibits 60 percent of the activity of heparin. Also compounds like heparan sulfate, without anticlotting activity, show the same antithrombotic effect of heparin. Heparin, besides its favorable anticoagulant and antithrombotic actions, has also a strong hemorrhagic activity. This effect is related to special structures of the damaged vessel wall and is not related to the anticoagulant and antithromboic actions. The minimum structure for the production of hemorrhage is a disaccharide composed of glucosamine C-6 sulfate and uronic acid with and 1 (4 glycosidic linkage. The hemorrhagic effect of heparin and fragments, including disaccharides, is abolished by ATP and/or myosin. The hemorrhagic disaccharides resemble the molecular conformation of ATP. Topical use of ATP in patients subjected to cardiovascular surgery with extracorporeal circulation significantly reduced the blood loss caused by heparin.