Extracellular Matrix Of Ostrich Articular Cartilage.

The composition and organization of the extracellular matrix of ostrich articular cartilage was investigated, using samples from the proximal and distal surfaces of the tarsometatarsus. For morphological analysis, sections were stained with toluidine blue and analyzed by polarized light microscopy. For biochemical analysis, extracellular matrix components were extracted with 4 M guanidinium chloride, fractionated on DEAE-Sephacel and analyzed by SDS-PAGE. Glycosaminoglycans were analyzed by electrophoresis in agarose gels. Structural analysis showed that the fibrils were arranged in different directions, especially on the distal surface. The protein and glycosaminoglycan contents of this region were higher than in the other regions. SDS-PAGE showed the presence of proteins with molecular masses ranging from 17 to 121 kDa and polydisperse components of 67, 80-100, and 250-300 kDa in all regions. The analysis of glycosaminoglycans in agarose-propylene diamine gels revealed the presence of only chondroitin-sulfate. The electrophoretic band corresponding to putative decorin was a small proteoglycan containing chondroitin-sufate and not dermatan-sulfate, unlike other cartilages. The higher amounts of proteins and glycosaminoglycans and the multidirectional arrangement of fibrils seen in the distal region may be correlated with the higher compression normally exerted on this region.2947-5

Ação da proteinase de trypanosoma cruzi sobre as imunoglobulinas IgA, IgM e IgG humanas

Orientador: Paulo Maria Ferreira de AraujoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: As imunoglobulinas humanas IgG e IgM séricas e IgA de colostro foram submetidas à ação da proteinase de padrões do extrato de epimastigotas (Araújo, 1979) foi purificada 56 vezes e contendo 1825 unidades/mg. As preparações de imunoglobulinas resultantes do tratamento enzimático em condições ótimas de pH (pH 7.0 e pH 3.1) e os controles adequados, foram analisados em eletroforese em gel de poliacrilamida com SDS (SDS 1% e DTT 100 mM), imunoeletroforese simples e bidimensional frente a imunessoros específicos. A degradação da molécula de IgG foi observada na eletroforese em gel de poliacrilamida, na comparação entre a preparação controle e a tratada com a enzima, onde a banda correspondente à cadeia pesada desaparece, havendo concentração de fragmentos de baixo peso molecular em nova banda de proteínas. A imunoeletroforese com os soros anti-IgG e anti-'delta¿, comprovam o comprometimento da molécula, pois desaparece a reatividade da cadeia pesada com o soro ant-'delta¿. Com as preparações de IgA, tratadas ou não com a enzima, não foi detectada fragmentação da molécula de imunoglobulina, nem nos testes de eletroforese em gel de poliacrilamida, nem nas reações de precipitação das imunoeletroforeses. Pouca ou nenhuma ação da proteinade sobre a IgA secretória ter ocorrido. ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digitalAbstract: Not informed.MestradoMestre em Ciências Biológica

Effect of magnesium chloride and guanidinum chloride on the extraction of components of extracellular matrix from chicken cartilage

In order to evaluate the effect of chaotropic agents on proteoglycan and non-collagenous proteins, chicken xiphoid cartilage was treated with guanidine-HCI and MgCl2 in different concentrations (1M to 5M), and different periods of time (12, 24, 48 and 72hr). The maximum yield of uronic acid was obtained with 3M MgCl2 (73.3 per cent). Concentrations of 4M and 5M of MgCl2 showed that much less uronic acid was removed, 55.3 per cent and 38.1 respectively. Extraction with 3M MgCl2 and 3M guanidine-HCl resulted better efficiency when performed for 48 hr. Analysis by SDS-PAGE of the extracts obtained with guanidine-HCl and MgCl, in different concentrations pointed out that most components are equally removed with the two solvents, showing that the extraction with MgCl2 is an alternative assay to remove non-collagenous proteins from extracellular matrix

Implications of obesity for tendon structure, ultrastructure and biochemistry: A study on Zucker rats

The extracellular matrix consists of collagen, proteoglycans and non-collagen proteins. The incidence of obesity and associated diseases is currently increasing in developed countries. Obesity is considered to be a disease of modern times, and genes predisposing to the disease have been identified in humans and animals. The objective of the present study was to compare the morphological and biochemical aspects of the deep digital flexor tendon of lean (Fa/Fa or Fa/fa) and genetically obese (fa/fa) Zucker rats. Ultrastructural analysis showed the presence of lipid droplets in both groups, whereas disorganized collagen fibril bundles were observed in obese animals. Lean animals presented a larger amount of non-collagen proteins and glycosaminoglycans than obese rats. We propose that the overweight and lesser physical activity in obese animals may have provoked the alterations in the composition and organization of extracellular matrix components but a genetic mechanism cannot be excluded. These alterations might be related to organizational and structural modifications in the collagen bundles that influence the mechanical properties of tendons and the progression to a pathological state. (C) 2011 Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Implications Of Obesity For Tendon Structure, Ultrastructure And Biochemistry: A Study On Zucker Rats.

The extracellular matrix consists of collagen, proteoglycans and non-collagen proteins. The incidence of obesity and associated diseases is currently increasing in developed countries. Obesity is considered to be a disease of modern times, and genes predisposing to the disease have been identified in humans and animals. The objective of the present study was to compare the morphological and biochemical aspects of the deep digital flexor tendon of lean (Fa/Fa or Fa/fa) and genetically obese (fa/fa) Zucker rats. Ultrastructural analysis showed the presence of lipid droplets in both groups, whereas disorganized collagen fibril bundles were observed in obese animals. Lean animals presented a larger amount of non-collagen proteins and glycosaminoglycans than obese rats. We propose that the overweight and lesser physical activity in obese animals may have provoked the alterations in the composition and organization of extracellular matrix components but a genetic mechanism cannot be excluded. These alterations might be related to organizational and structural modifications in the collagen bundles that influence the mechanical properties of tendons and the progression to a pathological state.43463-

Changes In The Connective Tissue Sheath Of Wistar Rat Nerve With Aging.

The alterations due to aging in the peripheral nerves can affect the physiology of these structures. Thus, the purpose of the present study was to describe the activity of the MMP-2 and MMP-9, as well as the structure and composition of the extracellular matrix of the rat sciatic nerve during maturation and aging. Our results have shown that the extracellular matrix of the sciatic nerve of 30-, 180- and 730-day-old Wistar rats present ultrastructural, morphometrical and biochemical changes during aging. The perineurium was the structure most affected by age, as evidenced by a decrease in thickness and in collagen fibril content. Cytochemical analysis detected proteoglycans in the basal membrane of Schwann cells and around perineural cells, as well as on the collagen fibrils of the perineurium and endoneurium at all ages. Biochemical analyses showed that the quantity of non-collagenous proteins was higher in 730-day-old animals compared to other ages, while the uronic acid content was higher in 30-day-old animals. Morphometrical analysis detected greater numbers of myelinated fibers and increased myelin thickness in 180-day-old animals. Zymography analysis detected greater amounts and activity of MMP-2 and MMP-9 in 180- and 730-day-old animals compared to younger rats. In conclusion, our results showed changes in the structural organization and composition of extracellular matrix of the sciatic nerve during aging, such as increase in the non-collagenous protein content and higher MMP-2 and MMP-9 activity, decrease in uronic acid concentration and in collagen fibril content in the perineurium, as well as degeneration of nerve fibers.196441-

Morphological alterations and increased gelatinase activity in the superficial digital flexor tendon of chickens during growth and maturation

The superficial digital flexor tendon (SDFT) connects the superficial digital flexor muscle to the digits and its main function is to participate in digit flexion. The SDFT presents different regions along its length, which adapt to different biomechanical forces. During growth and maturation, the tendon may present changes in the regions subjected to compression and tension, with variations in the composition of the extracellular matrix (ECM), in the arrangement of collagen fibers and cellularity. With the purpose of analyzing the morphological and biochemical alterations of ECM of tendons during the growth and maturation, Gallus domesticus were euthanized at 1, 5, and 8 months of age and their SDFT were divided into regions of tension/compression (Sp) and tension (Sd). From 1 month of age, the Sp region already presented fibrocartilage characteristics with cells similar to chondrocytes. At 5 and 8 months, the Sd region displayed formation of a new structure similar to bone matrix, and intense metachromasia. The animals of 5 and 8 months presented an increase in MMP-2 and -9 activities and a lower number of cells when compared with the animals of 1 month, in both regions. In conclusion, structural and biochemical alterations occur during the maturation process of the SDFT, involving a decrease in the number of cells and changes in the degradation and composition of the ECM3026964972CAPES - Coordenação de Aperfeiçoamento de Pessoal e Nível SuperiorFAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulosem informação2006/00044‐

Biochemical And Morphological Alterations Of The Extracellular Matrix Of Chicken Calcaneal Tendon During Maturation.

The region in tendons that surrounds bone extremities adapts to compression forces, developing a fibrocartilaginous structure. During maturation, changes occur in the amount and organization of macromolecules of the extracellular matrix of tendons, changing the tissue morphology. To study the effect of maturation on tendons, Pedrês chickens were sacrificed at 1, 5, and 8 months old and had the calcaneal tendon (CT) divided into proximal region, submitted to tension/compression forces (p), and distal region submitted to tension force (d). Morphological analysis of the p region showed the presence of fibrocartilage in all ages. In the central part of the fibrocartilage, near a diminishment of the metachromasy, there was also a development of a probable fat pad that increased with the maturation. The activity of MMP-2 and MMP-9 was higher at 5 and 8 months old, in both regions, compared with 1-month-old animals. In SDS-PAGE analysis, components with electrophoretic migration similar to decorin and fibromodulin increased with maturation, particularly in the d region. The Western blotting confirmed the increased amount of fibromodulin with maturation. In conclusion, our results show that process of maturation leads to the appearance of a probable fat pad in the center of the fibrocartilage of CT, with a reduced amount of glycosaminoglycans and an increased activity of MMPs.78949-95