Expression of heparanase in basal cell carcinoma and squamous cell carcinoma

Abstract: Background: Heparanase is an enzyme that cleaves heparan sulfate chains. Oligosaccharides generated by heparanase induce tumor progression. Basal cell carcinoma and squamous cell carcinoma comprise types of nonmelanoma skin cancer. Objectives: Evaluate the glycosaminoglycans profile and expression of heparanase in two human cell lines established in culture, immortalized skin keratinocyte (HaCaT) and squamous cell carcinoma (A431) and also investigate the expression of heparanase in basal cell carcinoma, squamous cell carcinoma and eyelid skin of individuals not affected by the disease (control). Methods: Glycosaminoglycans were quantified by electrophoresis and indirect ELISA method. The heparanase expression was analyzed by quantitative RT-PCR (qRTPCR). Results: The A431 strain showed significant increase in the sulfated glycosaminoglycans, increased heparanase expression and decreased hyaluronic acid, comparing to the HaCaT lineage. The mRNA expression of heparanase was significantly higher in Basal cell carcinoma and squamous cell carcinoma compared with control skin samples. It was also observed increased heparanase expression in squamous cell carcinoma compared to the Basal cell carcinoma. Conclusion: The glycosaminoglycans profile, as well as heparanase expression are different between HaCaT and A431 cell lines. The increased expression of heparanase in Basal cell carcinoma and squamous cell carcinoma suggests that this enzyme could be a marker for the diagnosis of such types of non-melanoma cancers, and may be useful as a target molecule for future alternative treatment.

Mucopolisacaridosis: características clínicas, diagnóstico y de manejo / Mucopolysaccharidosis: clinical features, diagnosis and management

Las mucopolisacaridosis (MPS) son un grupo de enfermedades raras (huérfanas), de baja prevalencia, caracterizadas por la deficiencia de enzimas que participan en el metabolismo de glucosaminglucanos (GAG) a nivel lisosomal. Se caracteriza por acumulación de GAG intracelular, produciendo alteraciones de múltiples órganos y sistemas. Su diagnóstico se basa en el conocimiento de las manifestaciones clínicas, realizar el análisis bioquímico para identificar el tipo de GAG que se está acumulando y confirmar el tipo de enfermedad con la determinación enzimática correspondiente. Su identificación es fundamental para iniciar un tratamiento oportuno, teniendo en cuenta que actualmente existe manejo transdisciplinario y tratamiento de reemplazo enzimático para MPS I (síndrome de Hurler), MPS II (síndrome de Hunter), MPS IV (síndrome de Morquio) y MPS VI (síndrome de Maroteaux-Lamy). En esta revisión se analizan cada uno de estos síndromes, su diagnóstico y tratamiento.

The mucopolysaccharidoses (MPS) are a group of rare (orphan) diseases, characterised by a deficiency of enzymes involved in the metabolism of glycosaminoglycans (GAGs) at lysosomal level. When there is a deficiency of a particular enzyme there is an accumulation of GAGs in the cells resulting in progressive cellular damage, which can affect multiple organ systems and lead to organ failure. Diagnosis is based on knowledge of the clinical manifestations, performing biochemical analyses to identify the type of GAG that is accumulating, and confirm the type of disorder with the corresponding enzymatic determination. Their identification is essential to initiate early treatment, taking into account that multidisciplinary management and enzyme replacement therapy is available for MPS I (Hurler syndrome), MPS II (Hunter syndrome), MPS IV (Morquio syndrome), and MPS VI (Maroteaux-Lamy syndrome. In this review, an analysis is made of each of these syndromes, as well as their diagnosis and treatment.

Increase of glyoosaminoglycans and metalloprotenases 2 and 9 in liver extracelllular matrix on early stages of extrahepatic cholestaiis / Aumento de glicosaminoglicanos e metaloproteinases 2 e 9 na matriz extracelular de fígado em estágios iniciais de colestase extra-hepática

Context Cholestasis produces hepatocellular injury, leukocyte infiltration, ductular cells proliferation and fibrosis of liver parenchyma by extracellular matrix replacement. Objective Analyze bile duct ligation effect upon glycosaminoglycans content and matrix metalloproteinase (MMPs) activities. Methods Animals (6-8 weeks; n = 40) were euthanized 2, 7 or 14 days after bile duct ligation or Sham-surgery. Disease evolution was analyzed by body and liver weight, seric direct bilirubin, globulins, gamma glutamyl transpeptidase (GGT), alkaline phosphatase (Alk-P), alanine and aspartate aminotransferases (ALT and AST), tissue myeloperoxidase and MMP-9, pro MMP-2 and MMP-2 activities, histopathology and glycosaminoglycans content. Results Cholestasis caused cellular damage with elevation of globulins, GGT, Alk-P, ALT, AST. There was neutrophil infiltration observed by the increasing of myeloperoxidase activity on 7 (P = 0.0064) and 14 (P = 0.0002) groups which leads to the magnification of tissue injuries. Bile duct ligation increased pro-MMP-2 (P = 0.0667), MMP-2 (P = 0.0003) and MMP-9 (P<0.0001) activities on 14 days indicating matrix remodeling and establishment of inflammatory process. Bile duct ligation animals showed an increasing on dermatan sulfate and/or heparan sulfate content reflecting extracellular matrix production and growing mitosis due to parenchyma depletion. Conclusions Cholestasis led to many changes on rats’ liver parenchyma, as so as on its extracellular matrix, with major alterations on MMPs activities and glycosaminoglycans content. .

Contexto Colestase produz lesão hepatocelular, infiltração leucocitária, proliferação de células ductulares e fibrose do parênquima hepático por matriz extracelular. Objetivo Analisar os efeitos da ligação do ducto biliar sobre conteúdo de glicosaminoglicanos e atividade de metaloproteinases de matriz (MMP). Métodos Animais (6-8 semanas; n = 40) foram eutanasiados 2, 7 ou 14 dias após ligação do ducto biliar ou falsa ligação. A evolução da doença foi analisada por peso corporal e do fígado, concentrações séricas de bilirrubina direta, globulinas, gama glutamil transpeptidase (GGT), fosfatase alcalina (Alk-P), alanina e aspartato aminotransfesases (ALT e AST), alterações teciduais de mieloperoxidase e metaloproteinases (MMP-9, pro MMP-2 e MMP-2), histopatologia e conteúdo de glicosaminoglicanos. Resultados A colestase causou dano celular com elevação dos níveis séricos de globulinas, GGT, Alk-P, ALT e AST. Houve também infiltração leucocitária observada pelo aumento na atividade de mieloperoxidase nos grupos 7 (P = 0,0064) e 14 dias (P = 0,0002) o que leva ao aumento das lesões no tecido. Ligação do ducto biliar aumentou as atividades de pro MMP-2 (P = 0,0677), MMP-2 (P = 0,0003) e MMP-9 (P<0,0001) aos 14 dias indicando remodelamento da matriz e estabelecimento de processo inflamatório. Animais com ligação do ducto biliar mostraram um aumento do conteúdo de dermatam sulfato e/ou heparam sulfato refletindo a produção de matriz extracelular e aumento de mitose devido a depleção do parênquima hepático. Conclusões Colestase causou várias mudanças no parênquima hepático de ratos, bem como em sua matriz extracelular, com importantes alterações na atividade ...

Mutation c.1190-1delG/N in intron 8 and c.1708G>C/N in exon 12 not reported in the IDUA gene developed a clinical phenotype of Scheie syndrome / Mutación c.1190-1delG/N en el intrón 8 y c.1708G>C/N en el exón 12 no reportada en el gen de IDUA desarrolló un fenotipo clínico de síndrome de Scheie

Mucopolysaccharidoses are a group of lysosomal storage disorders caused by deficiency of enzymes catalyzing the degradation of glycosaminoglycans. Mucopoly-saccharidosis I can present a wide range of phenotypic characteristics with three major recognized clinical entities: Hurler and Scheie syndromes represent phenotypes at the severe and mild ends of the clinical spectrum, respectively, and the Hurler-Scheie syndrome is intermediate in phenotypic expression. These are caused by the deficiency or absence of α-L-iduronidase, essential to the metabolism of both dermatan and heparan sulfate, and it is encoded by the IDUA gene. We report the case of a 34-year-old male patient with enzymatic deficiency of α-L-iduronidase, accumulation of its substrate and a previously unreported mutation in the IDUA gene that developed a phenotype of Scheie syndrome.

Las mucopolisacaridosis son un grupo de trastornos de almacenamiento lisosomal causada por la deficiencia de enzimas que catalizan la degradación de glicosaminoglicanos. La mucopolisacaridosis tipo I puede presentar un amplio rango de características fenotípicas englobadas en tres entidades clínicas reconocidas: los síndromes de Hurler y Scheie representan los fenotipos graves y leves del espectro clínico, respectivamente y el síndrome de Hurler-Scheie intermedio en la expresión fenotípica. Estos son causados por la deficiencia o ausencia de la α-L-iduronidasa esencial para el metabolismo del dermatán y el heparán sulfato y es codificada por el gen IDUA. Se presenta el caso de paciente masculino de 34 años de edad con deficiencia enzimática de α-L-iduronidasa, acumulación de su sustrato y una mutación en el gen IDUA, no reportada previamente, que desarrolló un fenotipo del síndrome de Scheie.

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. .

SKI306X inhibition of glycosaminoglycan degradation in human cartilage involves down-regulation of cytokine-induced catabolic genes

BACKGROUND/AIMS: SKI306X, a mixed extract of three herbs, Clematis mandshurica (CM), Prunella vulgaris (PV), and Trichosanthes kirilowii (TK), is chondroprotective in animal models of osteoarthritis (OA). The objectives of this study were to investigate its effect on interleukin (IL)-1beta-induced degradation of glycosaminoglycan (GAG) and the basis of its action in human OA cartilage, as well as to screen for the presence of inhibitors of matrix metalloproteinase (MMP)-13 and a disintegrin and metalloprotease with thrombospondin motifs (ADAMTS)-4 in SKI306X and its component herbs, as well as in fractions from SKI306X. METHODS: Human OA chondrocytes and cartilage explants were obtained during total knee replacements and incubated with IL-1beta +/- oncostatin M with or without SKI306X or its component herb extracts. GAG degradation was assayed in cartilage explants using a commercial kit. Expression of genes involved in cartilage destruction was measured by real-time polymerase chain reaction using chondrocyte RNA. SKI306X was fractionated by preparative liquid chromatography to test for the presence of inhibitors of MMP-13 and ADAMTS-4. RESULTS: SKI306X and PV inhibited IL-1beta-induced GAG release from cartilage explants, and SKI306X, CM, PV, and TK inhibited IL-1beta-induced MMP gene expression. Unexpectedly, SKI306X greatly stimulated IL-1beta + oncostatin M-induced ADAMTS-4 gene expression, probably due to its TK component. Some fractions of SKI306X also inhibited ADAMTS-4 activity. CONCLUSIONS: SKI306X and its herbal components inhibit GAG degradation and catabolic gene expression in human OA chondrocytes and cartilage explants. SKI306X likely also contains one or more ADAMTS-4 inhibitor.

Efecto del sulodexide sobre la capacidad de relajación y alteraciones estructurales de la arteria aorta en ratas diabéticas por estreptozotocina / Effect of sulodexide on aortic vasodilation capacity and associated morphological changes in rats with streptozotocin-induced diabetes

La disfunción endotelial (DE) se presenta en pacientes con hipercolesterolemia, hipertensión arterial, obesidad y diabetes mellitus. Evidencias sugieren un papel de los glicosaminoglicanos en la DE. Evaluamos el efecto del sulodexide (SLD), un glicosaminoglicano utilizado en el tratamiento de la albuminuria y la enfermedad isquémica en pacientes diabéticos, sobre la relajación arterial y los cambios morfológicos en un modelo experimental de diabetes tipo 1. La diabetes se indujo a ratas Sprague Dawley administrando estreptozotocina (STZ), 60 mg/kg, i.v. Los animales fueron distribuidos en los siguientes grupos: I= control, II= diabéticas, III: control + sulodexide, IV= diabéticas + sulodexide (15 mg/kg/día s.c). A los 3 meses fueron sacrificados, las aortas extraídas para evaluar la relajación vascular inducida por acetilcolina (Ach) y nitroprusiato de sodio en anillos precontraídos con fenilefrina. Fueron evaluadas histológicamente mediante microscopía de luz y coloraciones diversas. El SLD in vitro no modificó la tensión basal de los anillos arteriales en reposo o precontraídos con fenilefrina. La diabetes disminuyó la capacidad de relajación arterial en respuesta a la Ach en un 28,8-35,1% vs control, efecto que fue prevenido por SLD. No se observó diferencia significativa en la relajación inducida por nitroprusiato sódico entre los grupos. El estudio histológico en los animales diabéticos mostró alteraciones estructurales, particularmente en la íntima y la adventicia, cambios que fueron prevenidos por el tratamiento con SLD. Nuestros resultados apoyan la potencial utilidad terapéutica del SLD en el tratamiento de la disfunción endotelial.

Endothelial dysfunction (ED) is observed in patients with hypercholesterolemia, arterial hypertension, obesity and diabetes mellitus. Recent evidences suggest the involvement of glycosaminoglycans(GSG) in ED. We evaluated the effect of sulodexide (SLD), a natural GSG used in albuminuria and ischemic diabetes treatment, on arterial relaxation and vascular morphological changes in a diabetic type I model. Diabetes was induced, in Sprague-Dawley rats by streptozotocine (STZ) administration, 60 mg, iv. Rats were divided into four groups; I: control, II: diabetics, III: control + SLD, IV: diabetics treated with SLD (15 mg/day). After three months, phenylephrine precontracted aortic rings were used to evaluate acetylcholine (ACh) and sodium nitroprusside (NPS) relaxation capacities. Light microscopy of aorta was done with several staining procedures. In vitro, SLD did not change smooth muscle tone in resting or phenylephrine precontracted aortic rings. In diabetic rats, ACh relaxation was 28.8-35.1% lower than in control rats. Diabetic rats treated with SLD showed aortic ACh relaxation similar to control rats. No significative statistical difference was found in endothelium-independent NPS relaxation, between the different groups. Light microscopy histological studies revealed important morphological alterations, particularly in intima and adventitia layers of aortic artery; those changes were dramatically reversed in SLD treated rats. Our experiments support the conclusion that SLD is a potential drug for improving endothelial dysfunction in diabetes.

Brain sweet brain: importance of sugars for the cerebral microenvironment and tumor development / Cérebro doce cérebro: importância dos açúcares para o microambiente cerebral e o desenvolvimento tumoral

The extracellular matrix (ECM) in the brain tissue is a complex network of glycoproteins and proteoglycans that fills the intercellular space serving as scaffolding to provide structural framework for the tissue and regulate the behavior of cells via specific receptors - integrins. There is enormous structural diversity among proteoglycans due to variation in the core protein, the number of glycosaminoglycans chains, the extent and position of sulfation. The lectican family of proteoglycans interacts with growth factors, hyaluronan and tenascin forming a complex structure that regulates neuronal plasticity and ion homeostasis around highly active neurons. In this review, we will discuss the latest insights into the roles of brain glycoproteins as modulators of cell adhesion, migration, neurite outgrowth and glial tumor invasion.

A matriz extracelular (ECM) no tecido cerebral é formada por uma rede complexa de glicoproteínas e proteoglicanas que preenchem o espaço intercelular participando como estrutura de sustentação do arcabouço tecidual regulando a função celular por interações com receptores específicos - as integrinas. Existe enorme diversidade estrutural entre as proteoglicanas, devido à variação na proteína central (core), à quantidade de cadeias de glicosaminoglicanas, ao grau e posição de grupamentos sulfato na molécula. As proteoglicanas lecticanas interagem com fatores de crescimento, com hialuronana e tenascina formando uma estrutura complexa regulando a homeostase de íons e a plasticidade neuronal. Neste artigo de revisão serão apresentados dados relevantes da literatura sobre o papel das glicoproteínas no microambiente do tecido cerebral, como moduladores da neuritogênese, da adesão, migração celular e invasividade de células tumorais de origem glial.

Avaliação dos glicosaminoglicanos do tecido periuretral de pacientes com e sem prolapso genital / Evaluation of glycosaminoglycans of periurethral tissue in patients with and without pelvic organ prolapse

OBJETIVOS: Caracterizar e quantificar os subtipos de glicosaminoglicanos sulfatados (GAGs) existentes no tecido peri-uretral de pacientes com e sem prolapso genital. METODOS: Foram incluídas 35 pacientes que se submeteram a cirurgia vaginal para correção de distopias genitais e/ou incontinência urinária de esforço ou por outra condição benigna. As pacientes foram avaliadas por anamnese padronizada, exame físico e urodinâmico e agrupadas segundo a existência do prolapso genital. Durante o procedimento cirúrgico, amostras de aproximadamente 1,0 x 1,0 cm do tecido periuretral foram retiradas para avaliação. Os GAGs foram extraídos do tecido por proteólise e precipitação por ácido tricloroacético e caracterizados por eletroforese em gel de agarose. A quantificação foi feita por meio de densitometria a 525 nm do gel corado com azul de toluidina. Compararam-se os dados pela análise de variância (ANOVA). RESULTADOS: Nos grupos estudados, houve maior predomínio de dermatam sulfato (DS), em torno de 85 por cento do total de GAGs, seguido do condroitim sulfato (CS) e do heparam sulfato (HS). Observou-se aumento significativo dos GAGs totais, do DS e do HS em mulheres com prolapso genital. Não se observou diferença significante com relação ao CS. CONCLUSÃO: Este estudo demonstrou diferenças na matriz extracelular do tecido periuretral com aumento de GAGs totais, DS e HS nas mulheres com prolapso genital.

OBJECTIVE: To characterize and quantify periurethral tissue sulphated glycosaminoglycans (GAGs) in women with and without pelvic organ prolapse. STUDY DESIGN: Periurethral tissue was obtained from 35 women who underwent surgery for pelvic organ prolapse, for stress urinary incontinence, or for other gynecological benign conditions. Patients were submitted to a clinical history, physical and urodynamic examination and were divided in two groups according to genital prolapse. The standard biopsy with 1.0 x 1.0 cm was taken from periurethral tissue during surgery and assessed by biochemical methods. The GAGs were obtained by proteolysis and precipitated by trichloroacetic acid. The relative concentration of sulfated GAGs was determined by densitometry of toluidine blue stained gel using a spectrophotometer with a 525 nm wavelength. Data were compared using analysis of variance (ANOVA). RESULTS: In the two groups dermatan sulphate (DS) was the predominant glycosaminoglycan (85 percent), followed by chondroitin sulphate (CS) and heparan sulphate (HS). Women with pelvic organ prolapse had significantly more total GAGs, DS and HS. Differences in CS were not observed. CONCLUSIONS: This study showed altered biochemical characteristics in the extracellular matrix of periurethral tissue and also accumulation of GAGs, DS and CS, in women with pelvic organ prolapse.

Effect of low-dose electron radiation on rat skin wound healing

The aim of this study was to assess the effect of low-dose electron irradiation on morphological features of the wound healing process in rat skin. Surgical wounds were inflicted with a 2.3 x 1.4 cm template on 84 male rats that were assigned to 4 groups: IG1, immediately irradiated; IG2, irradiated 3 days after inflicting the wound; CG1 and CG2, control groups. Rats in IG1 and IG2 groups had their wounds exposed to 1 Gy of 6 MeV electron beam radiation, immediately after surgery and on the third postoperative day, respectively. Qualitative and histophotometric evaluations of tissue repair structures were carried out. Data were analyzed by ANOVA and Tukey's test (alpha = 0.05) and regression analysis. The repair process was delayed since the first sacrifice time in both irradiated groups, but in IG1, wound healing was closer to that of CG1; whereas in IG2, the delay was more pronounced. Based on the histological findings, it is possible to conclude that a low-dose of electron radiation delayed tissue repair in rat skin. The delay was longer in the skin irradiated 3 days after the beginning of tissue repair. However, the low-energy electron irradiation did not prevent wound healing.

O objetivo deste estudo foi avaliar o efeito da irradiação por baixa dose de elétrons sobre características morfológicas da reparação tecidual na pele de rato. Foram realizadas feridas cirúrgicas com um gabarito de 2,3 x 1,4 cm em 84 ratos machos, divididos em 4 grupos: IG1, irradiado imediatamente; IG2, irradiado 3 dias após a produção da ferida; CG1 e CG2, grupos controles. Os ratos dos grupos IG1 e IG2 tiveram suas feridas expostas a 1 Gy de radiação por elétrons com 6 MeV, imediatamente após a cirurgia e ao terceiro dia pós-operatório, respectivamente. Procedeu-se às avaliações qualitativas e histofotométrica das estruturas de reparação tecidual. Os dados foram submetidos a ANOVA e teste Tukey (a = 0,05) e análise de regressão. O processo de reparação apresentou-se atrasado desde o primeiro tempo de sacrifício em ambos os grupos irradiados, mas para IG1, a reparação tecidual foi similar a CG1. Por outro lado, para IG2, o retardo foi mais pronunciado. Com base nas avaliações histológicas, é possível concluir que uma baixa dose de radiação por elétrons retardou a reparação na pele de rato. O atraso foi maior na pele irradiada 3 dias após o início da reparação tecidual. No entanto, esta irradiação por elétrons de baixa energia não impediu a cicatrização.

Effect of nifedipine and amlodipine on dead space wound healing in rats.

Effect of two calcium channel blockers (CCBs) nifedipine and amlodipine, was studied on normal and steroid depressed wound healing in albino rats, using the dead space wound model. The drugs enhanced normal healing as evidenced by increase in tensile strength of 10 days old granulation tissue. There was neither a significant change in the hydroxyproline level (or collagen) nor a change in the glycosaminoglycan content in granulation tissue. However, lysyloxidase level was increased significantly. The increase in tensile strength could thus be attributed to better cross-linking and maturation of collagen rather than collagen synthesis per se. The drugs were also able to overcome steroid depressed wound healing. It is likely that the prohealing effects may be related to the improved antioxidant status too, since superoxide dismutase levels were observed to be higher in the CCB- treated animals.

Las mucopolisacaridosis / The mucopolysaccharidosis

Las mucopolisacaridosis (MPS) son errores innatos del metabolismo de los glicosaminoglicanos (GAG), que ocurren por déficit de alguna de las enzimas que degradan estas moléculas en los lisosomas. Esto conduce al depósito intralisosomal progresivo de GAG en diferentes tejidos, lo que explica el carácter multistémico de estas patologías. Las MPS, se presentan con una frecuencia aproximada de 1 caso en 10.000 a 25.000 recién nacidos vivos y son de herencia autosómica recesiva, salvo la MPS II o enfermedad de Hunter, que se hereda ligada al cromosoma X. Las características clínicas más frecuentes de las MPS son la presencia de rasgos faciales toscos, macrocefalia, opacidades corneales, disostosis múltiple, talla baja, valvulopatía mitroaórtica, hepatoesplenomegalia, hernias umbilical e inguinales, con o sin retraso del desarrollo sicomotor y con un deterioro neurológico progresivo. Salvo para las formas menos severas de MPS I, hasta ahora no hay un tratamiento efectivo para estas patologías, por lo que el daño sistémico progresivo produce la muerte entre los fines de la primera y de la cuarta década de la vida. En esta revisión se discuten las características clínicas de las MPS con las particularidades de cada fenotipo, el modo de confirmar el diagnóstico y los avances recientes en su tratamiento.

Protective effect of L-carnitine on gastric mucosal barrier in rats exposed to cold-restraint stress.

AIM: The protective effect of L-carnitine on stress-induced gastric mucosal injury was investigated in rats exposed to cold-restraint stress (CRS). METHODS: The animals were divided into four groups. Groups 1 and 3 received saline by intragastric gavage for 10 days. Groups 2 and 4 received L-carnitine (50 mg/Kg/day) in the same manner. Groups 3 and 4 were exposed to CRS in the form of immobilization at 4 degrees C for 4 h on day 10. Ulcer index, gastric acid secretion and hemoglobin leakage, and gastric mucosal mucin and PGE2 content were measured. RESULTS: In rats exposed to CRS, as compared to control rats (group 1), ulcer index was higher, gastric acid production was lower, hemoglobin leakage into the gastric lumen was increased, and gastric mucosal mucin and PGE content were reduced. L-carnitine treatment prior to CRS led to attenuation of changes in ulcer index, gastric acid secretion, amount of hemoglobin leakage into the gastric lumen and gastric PGE2 content. In rats receiving L-carnitine but not exposed to CRS, gastric acid secretion, mucin and PGE2 content of gastric mucosa were similar to those in control rats. CONCLUSION: L-carnitine decreases CRS-induced gastric mucosal injury.

Development of new heparin-like compounds and other antithrombotic drugs and their interaction with vascular endothelial cells

The anticlotting and antithrombotic activities of heparin, heparan sulfate, low molecular weight heparins, heparin and heparin-like compounds from various sources used in clinical practice or under development are briefly reviewed. Heparin isolated from shrimp mimics the pharmacological activities of low molecular weight heparins. A heparan sulfate from Artemia franciscana and a dermatan sulfate from tuna fish show a potent heparin cofactor II activity. A heparan sulfate derived from bovine pancreas has a potent antithrombotic activity in an arterial and venous thrombosis model with a negligible activity upon the serine proteases of the coagulation cascade. It is suggested that the antithrombotic activity of heparin and other antithrombotic agents is due at least in part to their action on endothelial cells stimulating the synthesis of an antithrombotic heparan sulfate.

Astroglial cells derived from lateral and medial midbrain sectors differ in their synthesis and secretion of sulfated glycosaminoglycans

Astroglial cells derived from lateral and medial midbrain sectors differ in their abilities to support neuritic growth of midbrain neurons in cocultures. These different properties of the two types of cells may be related to the composition of their extracellular matrix. We have studied the synthesis and secretion of sulfated glycosaminoglycans (GAGs) by the two cell types under control conditions and ß-D-xyloside-stimulated conditions, that stimulate the ability to synthesize and release GAGs. We have confirmed that both cell types synthesize and secrete heparan sulfate and chondroitin sulfate. Only slight differences were observed between the proportions of the two GAGs produced by the two types of cells after a 24-h labeling period. However, a marked difference was observed between the GAGs produced by the astroglial cells derived from lateral and medial midbrain sectors. The medial cells, which contain derivatives of the tectal and tegmental midline radial glia, synthesized and secreted ~2.3 times more chondroitin sulfate than lateral cells. The synthesis of heparan sulfate was only slightly modified by the addition of ß-D-xyloside. Overall, these results indicate that astroglial cells derived from the two midbrain sectors have marked differences in their capacity to synthesize chondroitin sulfate. Under in vivo conditions or a long period of in vitro culture, they may produce extracellular matrix at concentrations which may differentially affect neuritic growth

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

Effect of 2-deoxy-D-glucose on metabolism of glycosaminoglycans in normal and hypercholesterolemic rats.

Carbohydrates are the integral parts of glyco-conjugates and play an important role in cellular functions. 2-Deoxy-D-glucose (2-dGlc) is a sugar analogue of glucose and mannose and is reported to inhibit the lipid-linked saccharide formation involved in N-linked glycosylation of proteins. Administration of 2-dGlc (1 mg/100 g body weight) produced a decrease in the tissue total glycosaminoglycans level. We found that the activity of the enzymes involved in the biosynthesis of precursors of glycosaminoglycans (GAG) decreased, but that of the degrading enzymes increased. Thus, the decreased levels of GAG in tissues in 2-dGlc-administered rats occurs via enhanced degradation as well as decreased synthesis.

Distribuição comparativa dos glicosaminoglicanos em artérias e veias de diferentes mamíferos / Comparative distribution of glycosaminoglycans in arteries and veins of different mammals

Foi realizada análise comparativa sobre a distribuição dos glicosaminoglicanos de artérias e veias em ratos, cachorros e humanos. Os nossos resultados demonstraram que dermatam sulfato foi o principal glicosaminoglicano encontrado tanto para as artérias quanto para as veias estudadas. Entretanto, a proporção de dermatam sulfato foi maior nas veias do que nas artérias nas três espécies analisadas. Este aumento pode estar associado às diferenças estruturais e funcionais encontradas na parede destes dois tipos de vasos sangüíneos (nas veias a pressão sangüínea é significativamente mais baixa). Além disso, a quantidade total dos glicosaminoglicanos foi maior nas artérias do que nas veias, sendo as maiores concentrações encontradas nas aortas independentemente da espécie animal estudada. Estes achados abrem perspectiva para o melhor conhecimento das alterações das macromoléculas que possam estar relacionadas ao processo degenerativo vascular, especialmente nas transformações estruturais que as veias safenas sofrem, quando empregadas como enxertos na revascularização do miocárdio

Biochemical and dynamic studies of collagen from human normal skin and keloid tissue.

Keloids are exuberant scars, in which collagen, fibronectin and glycosaminoglycans are overdeposited. Biochemical analysis of the collagen isolated from normal skin and keloid tissue by pepsin treatment, indicated an increase in the type III and GAG content. Viscosity measurements of collagen from normal skin and keloid tissue were used in the present study to establish the interaction between collagen and GAG. Physico-chemical properties such as intrinsic viscosity, reduced viscosity and hydrated volume were computed from viscosity measurements. These measurements were also used to determine the denaturation temperature of collagen which was further confirmed by DSC measurements. Chondroitinase has been used in this study to probe the influence of GAG on the physico-chemical characteristic of keloid collagen.

A useful routine for biochemical detection and diagnosis of mucopolysaccharidoses

As mucopolissacaridoses (MPS) constituem, devido às suas características bioquímicas, genéticas e clínicas, um grupo grande e heterogêneo dentro das doenças lisôssomicas de depósito (LSD), e säo causadas pela deficiência de enzimas específicas que säo responsáveis pela quebra de gicosaminoglicanos (GAGs) em passos diferentes da sua rota de degradaçäo. Sendo as MPS responsáveis por aproximadamente 32 por cento dos erros inatos do metabolismo (EIM) e 54 por cento das LSD identificadas em nosso laboratório (Laboratório Regional dos Erros Inatos do Metabolismo (RLIEM), Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre), que é um centro de referência para o diagnóstico de LSD no Brasil, nós decidimos implantar uma rotina para detecçäo e o diagnóstico diferencial de MPS em pacientes com características clínicas sugestivas deste grupo de doenças.