Thesis--University of Tampere, 1987. / Includes bibliographical references.

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No description available.

Thesis (doctoral)--Lund University, 1997. / Added t.p. with thesis statement inserted.

Thesis (doctoral)--Lund University, 1997. / Added t.p. with thesis statement inserted.

Glycosaminoglycans (GAGs) are a family of linear bio-polysaccharides, which are heterogeneously modified with negatively charged sulfate and carboxylate groups. They are located on every cell surface, extracellular matrix or intracellular space in the body. GAGs are composed of alternating units of an amino sugars (glucosamine or galactosamine) and hexuronic acid/hexose (iduronic acid, glucoronic acid/ or galactose), which are linked by glycosidic bonds with different geometries. In recent years, GAGs have attracted considerable interest. GAGs play vital roles in fundamental biological processes, such as hemostasis, angiogenesis, cell signaling, growth and differentiation. Thus, GAGs contribute to a number of diseases such as thrombosis, cancer, inflammation, osteoarthritis and degenerative diseases. One of the most studied GAGs is heparin, which is widely used as an anticoagulant and is also implicated in other biological processes. Despite its extensive clinical use, heparin continues to suffer from major problems, such as life threatening hemorrhagic complications and heparin-induced thrombocytopenia. These activities originate from the large number of glycan sequences generated during its biosynthesis. Many different enzymes act in a non-template fashion to produce heparin chains with various chain lengths, sulfation and acetylation patterns. Their inherent heterogeneity, complexity and highly anionic nature have seriously limited the development of tools for rapid identification of sequences critical for many biological activities. A RPIP-UPLC MS protocol was developed to separate and characterize structures of heparin oligosaccharides prepared through enzymatic cleavage process and chemoenzymatic synthesis. In designing such protocol, several UPLC and MS parameters were considered. An efficient separation of each oligosaccharide mixture was achieved with different ion-pairing reagents. Yet, the structural elucidation of the multiple chromatographic peaks was hindered by the heterogeneity inherent in these mixtures even with supposedly defined standards. In order to elucidate the structures of these complex molecules, we utilized a strategy, which exploits the ease with which sulfate groups can be fragmented during MS ionization. A systematic increment of the MS cone voltage was employed starting from a minimum dissociation voltage, where the intact molecule is preserved, to a high enough dissociation voltage, where the only core oligosaccharide backbone was retained. This allowed identifying the number of sulfate groups and the core structures. However, positions of substituents were difficult to pinpoint because of the phenomenal number of possibilities. Such analysis would require tandem MS/MS–based approaches.

The goal of this thesis was to investigate the interplay between sodium, glycosaminoglycans, vascular stiffness, and hypertension. In contrast to the traditional view of salt-dependent hypertension, recent studies have found that sodium accumulation can occur without commensurate fluid retention. Researchers hypothesise that this sodium is stored non-osmotically via association with negatively charged glycosaminoglycans (GAGs) in the extracellular matrix. The interaction of sodium and GAGs, the influence of sodium on GAG production, and the ability of GAGs to affect vascular stiffness are of key interest. This thesis first investigates the link between hypertension, vascular stiffness, and GAGs in ex vivo human aortae. Aortae from hypertensive donors were found to be stiffer than normotensive controls even after controlling for both pressure and age, a novel finding in humans. In these aortae, hypertension was associated with GAG remodelling, but not with changes in total GAG content. Next, an interventional rat study is presented to examine the effects of dietary salt on vascular stiffness and GAGs, and to distinguish between salt-dependent and blood pressure-dependent effects. In vivo vascular stiffness was found to be salt-dependent but pressure-independent, with ex vivo stiffness unaffected by salt. Ex vivo stiffness was also independent of aortic GAG content, similar to the human aortae described previously. GAG content in the skin was both salt-dependent and pressure-dependent. Finally, this thesis closes with an interventional study in humans. This study was designed to examine the effects of diuretic-induced salt loss on sodium storage, GAGs, and haemodynamics. An eight-day diuretic course corresponded to a ~10% reduction in skin sodium content, without associated water loss or cardiovascular changes. GAG mRNA expression was decreased in the skin, suggesting reduced GAG content. Pilot work from this study supports the use of 23Na MRI as a non-invasive measurement of skin sodium, but only for pre- vs post-treatment comparisons rather than absolute quantification. In conclusion, this thesis demonstrates that both salt and blood pressure influence GAG accumulation and distribution, but that GAGs do not directly affect vascular stiffness. However, GAGs do play a direct role in osmotically inactive sodium storage, which may modulate development of hypertension.

A osteoartrite é a causa mais comum de claudicação em cavalos e, frequentemente está associada com a queda de desempenho e abandono precoce das atividades esportivas. Numerosos estudos têm investigado o potencial da função dos condroprotetores na desaceleração do processo degenerativo e no reparo da cartilagem articular. A finalidade deste estudo foi investigar o efeito da administração oral de glucosamina, condroitim sulfato e ácido hialurônico associados sobre a evolução clínica, radiológica, e glicosaminoglicanos (GAGs) da urina, do líquido sinovial e sérico de cavalos acometidos por osteoartrite. Foram utilizados seis equinos, com idades entre seis e doze anos, machos ou fêmeas, submetidos ao mesmo manejo nutricional. Estes animais receberam doses diárias de condroitim sulfato (CS) (2,8 g), ácido hialurônico (AH) (0,1g), glucosamina (3,1 g), via oral, por 25 dias. Exames clínicos e radiográficos foram realizados anteriormente e após o tratamento. Amostras de urina, líquido sinovial, e sangue foram coletados antes da primeira administração do suplemento; a cada 5 dias durante o tratamento e a cada 7 dias após o tratamento, durante 55 dias. Os glicosaminoglicanos urinários foram identificados por eletroforese em gel de agarose após cromatografia de troca iônica e quantificados por densitometria. A determinação de AH sérico foi realizada por ELISA. Após proteólise do líquido sinovial o CS e a AH foram igualmente identificados por eletroforese e quantificados por densitometria. No início do experimento, as concentrações médias urinárias de CS, DS, HS e GAGs totais (2,96 mg/l, 0,66 mg/l, 0,42 mg/l, 4,05 mg/l respectivamente) foram inferiores as médias urinárias, logo após o tratamento (5,38 mg/l, 1,30 mg/l, 0,96 mg/l, 7,64 mg/l respectivamente) (p<0,05) e similares após 30 dias (4,24 mg/l, 1,09 mg/l, 0,36 mg/l, 5,69 mg/l). A concentração sérica de AH aumentou após o tratamento e ao final do experimento em relação do início dos mesmos (10,61 ng/ml, 12,58 ng/ml, 21,08 ng/ml respectivamente) (p<0,05). O CS do líquido sinovial apresentou comportamento similar ao CS urinário (início: 76,13 µg/ml, final do tratamento: 93,05 µg/ml, final do experimento: 61,61µg/ml). Já o AH no líquido sinovial não sofreu alterações significativas (início: 440,07 µg/ml, final do tratamento: 351,15 µg/ml, final do experimento: 375,99 µg/ml) apesar da tendência a diminuição. Concluiu-se que a administração oral de glucosamina, CS e AH associados apresenta uma tendência ao aumento dos GAGs urinários e do CS do líquido sinovial imediatamente após o tratamento, com diminuição até 30 dias; aumento sérico do AH e manutenção da concentração de AH no líquido sinovial, com tendência a diminuição. / Osteoarthritis is the most common cause of lameness in horses, and often is frequently associated with poor performance and early end of sports activities. Numerous studies have investigated the potential function of chondroprotective drugs in slow down the degenerative process and helping to repair the joint cartilages. The purpose of this study was to investigate the effect of oral administration of glucosamine, chondroitin sulfate and hyaluronic acid associated with the clinical, radiological, and urinary glycosaminoglycans (GAGs), in the serum and synovial fluid of horses affected by osteoarthritis. We used six horses, aged between six and twelve years old, male or female, undergoing the same nutritional management. These animals received daily doses of condroitim sulfate (CS) (2.8 g), hyaluronic acid (HA) (0.1 g), glucosamine (3.1 g), oral route, for 25 days. Clinical and radiographic examinations were performed before and at the end of treatment. Samples of urine, synovial fluid and serum were collected before the first administration of the supplement, and every 5 days during the treatment and every 7 days after the end of the treatment, for a total of 55 days. The urinary glycosaminoglycans have been identified for agarose gel electrophoresis after ion-exchange chromatography on Q-Sepharose and quantified by densitometry. The determination of serum HA was performed by ELISA. After the sinovial liquid proteolysis the CS and the HA have been equally identified for eletrophoresis and quantified by densitometry. In the beginning of this study the avarage of urinary concentrations of CS, DS, HS and total GAGs (2.96 mg/l, 0.66 mg/l, 0.42 mg/l, 4.05 mg/l respectively) have been inferior the urinary averages, right after the treatment (5.38 mg/l, 1.30 mg/l, 0.96 mg/l, 7.64 mg/l respectively)(p< 0,05) and similar after 30 days (4.24 mg/l, 1.09 mg/l, 0.36 mg/l, 5.69 mg/l respectively). The HA serum concentration increased after treatment and the end of the experiment regarding the inicial values (10.61 ng/ml, 12.58 ng/ml, 21.08 ng/ml respectively) (p<0.05). The synovial fluid CS showed a similar behavior to the urinary CS (beginning: 76.13 µg/ml, end of treatment: 93.05 µg/ml, end of the experiment: 61.61 µg/ml). But the synovial fluid HA did not change significantly (beginning: 440.07 µg/ml, end of treatment: 351.15 µg/ml, end of the experiment: 375.99 µg/ml) despite the tendency to decrease. It was concluded that oral administration of glucosamine, CS and HA associated shows a tendency to increase the urinary GAGs and CS in the synovial fluid immediately after treatment, with reduction in 30 days; increase of serum HA and maintenance of the concentration of HA in synovial fluid, with a tendency to decrease.

Introdução: a cistite intersticial é doença crônica do trato urinário inferior cujos sintomas são: aumento da freqüência urinária, nictúria, dor pélvica ou perineal que piora com a repleção vesical e melhora com a micção. A etiopatogenia não é totalmente conhecida, mas há indícios de que os glicosaminoglicanos e proteoglicanos que revestem o urotélio vesical possam participar da sua gênese. A perda destes componentes protetores facilitaria o contato de íons e solutos presentes na urina com as porções mais profundas do urotélio desencadeando e perpetuando um processo inflamatório local. Para tentar entender seu metabolismo, investigamos o comportamento dos glicosaminoglicanos na urina e no tecido (biópsia do urotélio vesical) de pacientes portadoras de cistite intersticial e de incontinência urinária de esforço genuína. Casuística e métodos: o perfil e expressão gênica de glicosaminoglicanos no tecido, e o perfil dos glicosaminoglicanos da urina de 11 pacientes com cistite intersticial foram comparados aos de 11 pacientes com incontinência urinária de esforço. A análise estatística foi feita através de teste T e Anova, considerando significativos valores p<0,05. Resultados: verificamos que pacientes com cistite intersticial excretam menor concentração de glicosaminoglicanos na urina do que as portadoras de incontinência urinária de esforço (0,45 ± 0,11 x 0,62 ± 0,13 g/mg creatinina, p<0,05), porém sem redução do conteúdo de glicosaminoglicanos no urotélio. Na imunofluorescência o urotélio de pacientes com cistite intersticial mostrou maior marcação de TGF-beta, decorim (um proteoglicano de condroitim/dermatam sulfato), fibronectina e de ácido hialurônico. Foi identificada menor expressão gênica (PCR em tempo real) das sintases e uma hialuronidase do ácido hialurônico no urotélio das cistites intersticiais. Conclusão: a combinação desses resultados sugere que os glicosaminoglicanos podem estar relacionados ao processo contínuo de inflamação e remodelamento do urotélio disfuncional presente na cistite intersticial. O estudo da expressão gênica pode representar uma altenativa para o entendimento da doença. / Introduction: interstitial cystitis is a chronic disease of the lower urinary tract whose symptoms are: increased urinary frequency, nocturia, perineal or pelvic pain that worses with bladder filling and improves with urination. The pathogenesis is not fully known, but there is evidence that proteoglycans and glycosaminoglycans lining the bladder urothelium can participate in its genesis. The loss of these protective compounds facilitate the contact of ions and solutes in the urine with deeper portions of bladder wall triggering and perpetuating a local inflammatory process. We investigated GAG behavior in urine and tissue (biopsy of bladder urothelium) of patients with IC/PBS and genuine stress urinary incontinence (SUI) in an attempt to better understand its metabolism. Patients and Methods: gene expression and glycosaminoglycans profile in tissue, and glycosaminoglycans profile in urine of 11 patients with interstitial cystitis were compared to 11 patients with pure urinary stress incontinence. Statistical analysis were performed using t Student test and Anova, considering significant when p<0,05. Results: patients with interstitial cystitis excreted lower concentration of glycosaminoglycans in urine when compared to those with pure urinary stress incontinence (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 glycosaminoglycans in the urothelium of both patients. The immunofluorescence study showed that patients with interstitial cystitis had a stronger staining of TGF-beta, decorin (a proteoglycan of chondroitin/dermatan sulfate), fibronectin and hyaluronic acid. We were able to indentify by real-time PCR lower gene expression of hyaluronic acid synthases and hyaluronidase in the urothelium of patients with interstitial cystitis. Conclusion: the results suggest that glycosaminoglycans may be related to the ongoing process of inflammation and remodeling of the dysfunctional urothelium that is present in the interstitial cystitis. The study of the gene expression may represent an alternative to understand the disease

La maurocalcine (MCa) est un peptide/toxin de 33 acides aminés initialement isolé du venin d'un scorpion Tunisien Scorpio maurus palmatus. Depuis ce travail pionnier, la molécule a pu être produite par synthèse chimique sans altération structurale. Trois raisons font que ce peptide est particulièrement intéressant. D'une part, il présente une homologie de séquence avec un domaine de canal calcium dépendant du potentiel qui est impliqué dans le couplage excitation-contraction. Cette homologie est utile pour déchiffrer les bases mécanistiques de la mobilisation calcium du réticulum sarcoplasmique. D'autre part, la MCa est un activateur puissant du récepteur à la ryanodine, déclenchant de cette manière la libération de calcium des stocks intracellulaires. Finalement, ce peptide a une valeur technologique en raison de sa capacité à transporter des composés imperméables au travers de la membrane plasmique. Dans ce travail de thèse, j'ai planifié de nouveaux analogues plus efficaces de la maurocalcine, soit par des substitutions uniques d'acides aminés ou en remplaçant l'ensemble des cystéines par des acides aminés isostériques. Ces analogues possèdent des efficacités de pénétration cellulaire équivalente ou supérieure, présentent des toxicités cellulaires limitées et n'ont pas d'activités pharmacologiques sur le récepteur à la ryanodine. J'ai analysé l'interaction de ces analogues avec des lipides membranaires et des glycosaminoglycans de surface, et le rôle de ces composants dans la pénétration cellulaire de la MCa. L'entrée cellulaire de la MCa se produit par macropinocytose quand ce peptide se fixe à la streptavidine.