scholarly journals Distinct effects of different matrix proteoglycans on collagen fibrillogenesis and cell-mediated collagen reorganization

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Dongning Chen ◽  
Lucas R. Smith ◽  
Gauri Khandekar ◽  
Pavan Patel ◽  
Christopher K. Yu ◽  
...  
Keyword(s):  
Complex Mixture ◽  
Collagen Matrices ◽  
Collagen Fibrillogenesis ◽  
Large Matrix ◽  
Fibrillar Collagens ◽  
Additional Protein ◽  
Carbohydrate Components ◽  
And Function ◽  
Opposing Effects

Abstract The extracellular matrix (ECM) is a complex mixture composed of fibrillar collagens as well as additional protein and carbohydrate components. Proteoglycans (PGs) contribute to the heterogeneity of the ECM and play an important role in its structure and function. While the small leucine rich proteoglycans (SLRPs), including decorin and lumican, have been studied extensively as mediators of collagen fibrillogenesis and organization, the function of large matrix PGs in collagen matrices is less well known. In this study, we showed that different matrix PGs have distinct roles in regulating collagen behaviors. We found that versican, a large chondroitin sulfate PG, promotes collagen fibrillogenesis in a turbidity assay and upregulates cell-mediated collagen compaction and reorganization, whereas aggrecan, a structurally-similar large PG, has different and often opposing effects on collagen. Compared to versican, decorin and lumican also have distinct functions in regulating collagen behaviors. The different ways in which matrix PGs interact with collagen have important implications for understanding the role of the ECM in diseases such as fibrosis and cancer, and suggest that matrix PGs are potential therapeutic targets.

scholarly journals Distinct effects of different matrix proteoglycans on collagen fibrillogenesis and cell-mediated collagen reorganization

2020 ◽  
Author(s):  
Dongning Chen ◽  
Lucas R. Smith ◽  
Gauri Khandekar ◽  
Pavan Patel ◽  
Christopher K. Yu ◽  
...  
Keyword(s):  
Chondroitin Sulfate ◽  
Core Protein ◽  
Complex Mixture ◽  
List Type ◽  
Collagen Fibrillogenesis ◽  
Fibrous Network ◽  
Large Matrix ◽  
Carbohydrate Components ◽  
And Function

AbstractThe extracellular matrix (ECM) is a complex mixture composed of fibrillar collagens as well as additional protein and carbohydrate components. Proteoglycans (PGs) contribute to the heterogeneity of the ECM and play an important role in its structure and function. While the small leucine rich proteoglycans (SLRPs), including decorin and lumican, have been studied extensively as mediators of collagen fibrillogenesis and organization, the function of large matrix PGs in collagen matrices is less well known. In this study, we showed that different matrix PGs have distinct roles in regulating collagen behaviors. We found that versican, a large chondroitin sulfate PG, promotes collagen fibrillogenesis in a turbidity assay and upregulates cell-mediated collagen compaction and reorganization, whereas aggrecan, a structurally-similar large PG, has different and often opposing effects on collagen. Compared to versican, decorin and lumican also have distinct functions in regulating collagen behaviors. The different ways in which matrix PGs interact with collagen have important implications for understanding the role of the ECM in diseases such as fibrosis and cancer, and suggest that matrix PGs are potential therapeutic targets.HighlightsSmall leucine rich proteoglycans (SLRPs) and large chondroitin sulfate (CS) proteoglycans (PGs) have distinct effects on collagen fibrous network behavior.Unlike other matrix proteoglycans, versican promotes collagen fibrillogenesis in an in vitro spectrophotometric (turbidity) assay.The versican core protein has a larger impact on collagen behavior in a fibrillogenesis assay than its glycosaminoglycan chains do.Versican increases the diameter of collagen fibers and the porosity of collagen fibrous networks, unlike aggrecan and SLRPs.The addition of versican to collagen does not alter fibroblast contractility but leads to enhanced cell-mediated collagen reorganization and contraction.

High Resolution Histochemical Studies on the Surface of the External Vesicular Membrane of Cysticercus Cellulosae

1977 ◽  
Vol 35 ◽  
pp. 452-453
Author(s):  
A. Sosa ◽  
S. Alva ◽  
H. Girόn ◽  
W. Hohman
Keyword(s):  
Alimentary Tract ◽  
Iron Hydroxide ◽  
Colloidal Iron ◽  
Cysticercus Cellulosae ◽  
Vesicular Membrane ◽  
Carbohydrate Components ◽  
And Function ◽  
Host Parasite ◽  
Host Tissues

The external vesicular membrane of the bladder of Cysticercus cellulosae serves two essential purposes for the survival of this endoparasite: (1) the principal organ for transporting substances to and from the environment, and (2) the principal surface through which the host-parasite relationships are established. The first is important because C. cellulosae does not possess an alimentary tract and the external vesicular membrane performs the role of acquiring nutrients from the environment. The second is important because the morpho-physiological connections between the parasite and host tissues are formed and maintained by this surface. Therefore the study of the structure and function of this surface is important to elucidate both aspects of membrane transport and host-parasite interrelationships. The purpose of this study is to use alcian blue- lanthanum, concanavalin A (con-A) and colloidal iron hydroxide (CIH) methods to demonstrate the presence and distribution of carbohydrate components and charge density on the surface of the external vesicular membran of C. cellulosae, All cysticerci used were obtained from anconeous muscle of parasitized hogs in Mexico City.

scholarly journals The Role of Lysyl Oxidase Enzymes in Cardiac Function and Remodeling

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1483 ◽  
Author(s):  
Cristina Rodríguez ◽  
José Martínez-González
Keyword(s):  
Lysyl Oxidase ◽  
Critical Role ◽  
Cardiac Cells ◽  
Primary Role ◽  
Cellular Phenotype ◽  
Fibrillar Collagens ◽  
Reactive Aldehydes ◽  
And Function ◽  
Cell Signaling Pathways

Lysyl oxidase (LOX) proteins comprise a family of five copper-dependent enzymes (LOX and four LOX-like isoenzymes (LOXL1–4)) critical for extracellular matrix (ECM) homeostasis and remodeling. The primary role of LOX enzymes is to oxidize lysyl and hydroxylysyl residues from collagen and elastin chains into highly reactive aldehydes, which spontaneously react with surrounding amino groups and other aldehydes to form inter- and intra-catenary covalent cross-linkages. Therefore, they are essential for the synthesis of a mature ECM and assure matrix integrity. ECM modulates cellular phenotype and function, and strikingly influences the mechanical properties of tissues. This explains the critical role of these enzymes in tissue homeostasis, and in tissue repair and remodeling. Cardiac ECM is mainly composed of fibrillar collagens which form a complex network that provides structural and biochemical support to cardiac cells and regulates cell signaling pathways. It is now becoming apparent that cardiac performance is affected by the structure and composition of the ECM and that any disturbance of the ECM contributes to cardiac disease progression. This review article compiles the major findings on the contribution of the LOX family to the development and progression of myocardial disorders.

Scanning electron microscopic study of collagen fibrillogenesis and extracellular compartmentalization in the chick embryo tendon

1986 ◽  
Vol 44 ◽  
pp. 208-209
Author(s):  
Grace C.H. Yang
Keyword(s):  
Chick Embryo ◽  
Extracellular Space ◽  
Fibroblast Cell ◽  
Collagen Fibrils ◽  
Electron Microscopic ◽  
Voltage Electron ◽  
Scanning Electron Microscopic Study ◽  
Microscopic Studies ◽  
And Function

The size and organization of collagen fibrils in the extracellular matrix is an important determinant of tissue structure and function. The synthesis and deposition of collagen involves multiple steps which begin within the cell and continue in the extracellular space. High-voltage electron microscopic studies of the chick embryo cornea and tendon suggested that the extracellular space is compartmentalized by the fibroblasts for the regulation of collagen fibril, bundle, and tissue specific macroaggregate formation. The purpose of this study is to gather direct evidence regarding the association of the fibroblast cell surface with newly formed collagen fibrils, and to define the role of the fibroblast in the control and the precise positioning of collagen fibrils, bundles, and macroaggregates during chick tendon development.

Role of the Cilia Membrane in Control of Microtubule Sliding

1980 ◽  
Vol 38 ◽  
pp. 612-615
Author(s):  
Edna S. Kaneshiro
Keyword(s):  
Control Mechanism ◽  
Beat Frequency ◽  
Surface Membrane ◽  
Ciliary Membrane ◽  
Ciliary Beating ◽  
Ciliary Reversal ◽  
Voltage Dependent ◽  
Reversal Mechanism ◽  
And Function

It is currently believed that ciliary beating results from microtubule sliding which is restricted in regions to cause bending. Cilia beat can be modified to bring about changes in beat frequency, cessation of beat and reversal in beat direction. In ciliated protozoans these modifications which determine swimming behavior have been shown to be related to intracellular (intraciliary) Ca2+ concentrations. The Ca2+ levels are in turn governed by the surface ciliary membrane which exhibits increased Ca2+ conductance (permeability) in response to depolarization. Mutants with altered behaviors have been isolated. Pawn mutants fail to exhibit reversal of the effective stroke of ciliary beat and therefore cannot swim backward. They lack the increased inward Ca2+ current in response to depolarizing stimuli. Both normal and pawn Paramecium made leaky to Ca2+ by Triton extrac¬tion of the surface membrane exhibit backward swimming only in reactivating solutions containing greater than IO-6 M Ca2+ Thus in pawns the ciliary reversal mechanism itself is left operational and only the control mechanism at the membrane is affected. The topographic location of voltage-dependent Ca2+ channels has been identified as a component of the ciliary mem¬brane since the inward Ca2+ conductance response is eliminated by deciliation and the return of the response occurs during cilia regeneration. Since the ciliary membrane has been impli¬cated in the control of Ca2+ levels in the cilium and therefore is the site of at least one kind of control of microtubule sliding, we have focused our attention on understanding the structure and function of the membrane.

POPDC proteins and cardiac function

2019 ◽  
Vol 47 (5) ◽  
pp. 1393-1404 ◽  
Author(s):  
Thomas Brand
Keyword(s):  
Potential Role ◽  
Striated Muscle ◽  
Short Review ◽  
Effector Proteins ◽  
Muscle Disease ◽  
Disease Genes ◽  
Protein Protein Interaction ◽  
Interaction Partners ◽  
And Function

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.

Role of the 807 C/T Polymorphism of the α2 Gene in Platelet GP Ia Collagen Receptor Expression and Function

1999 ◽  
Vol 81 (06) ◽  
pp. 951-956 ◽  
Author(s):  
J. Corral ◽  
R. González-Conejero ◽  
J. Rivera ◽  
F. Ortuño ◽  
P. Aparicio ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Cell Types ◽  
Receptor Expression ◽  
Case Control Studies ◽  
Platelet Surface ◽  
Vitro Analysis ◽  
And Function ◽  
In Vitro Analysis

SummaryThe variability of the platelet GP Ia/IIa density has been associated with the 807 C/T polymorphism (Phe 224) of the GP Ia gene in American Caucasian population. We have investigated the genotype and allelic frequencies of this polymorphism in Spanish Caucasians. The T allele was found in 35% of the 284 blood donors analyzed. We confirmed in 159 healthy subjects a significant association between the 807 C/T polymorphism and the platelet GP Ia density. The T allele correlated with high number of GP Ia molecules on platelet surface. In addition, we observed a similar association of this polymorphism with the expression of this protein in other blood cell types. The platelet responsiveness to collagen was determined by “in vitro” analysis of the platelet activation and aggregation response. We found no significant differences in these functional platelet parameters according to the 807 C/T genotype. Finally, results from 3 case/control studies involving 302 consecutive patients (101 with coronary heart disease, 104 with cerebrovascular disease and 97 with deep venous thrombosis) determined that the 807 C/T polymorphism of the GP Ia gene does not represent a risk factor for arterial or venous thrombosis.

Von Willebrand disease and Weibel-Palade bodies

2010 ◽  
Vol 30 (03) ◽  
pp. 150-155 ◽  
Author(s):  
J. W. Wang ◽  
J. Eikenboom
Keyword(s):  
Platelet Adhesion ◽  
Coagulation Factor ◽  
Von Willebrand Disease ◽  
Inflammatory Factors ◽  
Limited Data ◽  
Storage Organelle ◽  
And Function ◽  
Von Willebrand ◽  
Willebrand Factor

SummaryVon Willebrand factor (VWF) is a pivotal haemostatic protein mediating platelet adhesion to injured endothelium and carrying coagulation factor VIII (FVIII) in the circulation to protect it from premature clearance. Apart from the roles in haemostasis, VWF drives the formation of the endothelial cell specific Weibel-Palade bodies (WPBs), which serve as a regulated storage of VWF and other thrombotic and inflammatory factors. Defects in VWF could lead to the bleeding disorder von Willebrand disease (VWD).Extensive studies have shown that several mutations identified in VWD patients cause an intracellular retention of VWF. However, the effects of such mutations on the formation and function of its storage organelle are largely unknown. This review gives an overview on the role of VWF in WPB biogenesis and summarizes the limited data on the WPBs formed by VWD-causing mutant VWF.

Grape Seeds Extract as Brain Food: A Review

2017 ◽  
Vol 9 (1) ◽  
Author(s):  
Souad El Gengaihi ◽  
Doha H. Abou Baker
Keyword(s):  
Antioxidant Activities ◽  
Complex Mixture ◽  
Grape Seed Extract ◽  
Grape Seed ◽  
Seed Extract ◽  
Amyloid Peptide ◽  
Grape Seeds ◽  
Potential Benefits ◽  
Reduced Risk

Interest in the biological role of bioactive compounds present in medicinal herbs has increased over the last years. Of particular interest are plants that have an anti-Alzheimer activities. Several plants can be useful for Alzheimer (AD) management. Such as these which have anti-inflammatory activity, acetylcholinesterase (AChE) inhibitory action, antiapoptotic, slow the aggregation of amyloid peptide and antioxidant activities. Grape seed extract (GSE) is a complex mixture of several compounds, mostly represented by polyphenols and flavonoids. Their consumption is safe and is recognized to exert several health benefits. GS flavonoids have been associated with the reduced risk of chronic diseases, we present some findings on the potential benefits of GSE for the treatment of AD.

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