heparitin-sulfate and Diabetes-Mellitus

Diabetes mellitus causes a wide range of metabolic derangements with multiple organ damage. The microvascular and macrovascular complications of diabetes result partly from the damage to the glycosaminoglycans (GAG) in the basement membrane. GAGs are negatively charged polysaccharides with repeating disaccharide units. They play a significant role in cellular proliferation and signal transduction. Destruction of extracellular matrix results in diseases in various organs including myocardial fibrosis, retinal damage and nephropathy. To substitute the natural GAGs pharmacotherapeutically, they have been synthesized by using basic disaccharide units. Among the four classes of GAGs, heparin is the most widely studied. Recent studies have revealed multiple significant GAG-protein interactions suggesting their use for the management of diabetic complications. Moreover, they can act as biomarkers for assessing the disease progression. A number of GAG-based therapeutic agents are being evaluated for managing diabetic complications. The current review provides an outline of the role of GAGs in diabetes while covering their interaction with different molecular players that can serve as targets for the diagnosis, management and prevention of diabetes and its complications. The medicinal chemistry and clinical pharmacotherapeutics aspects have are covered to aid in the establishment of GAG-based therapies as a possible avenue for diabetes.

Topics: Diabetes Complications; Diabetes Mellitus; Disaccharides; Glycosaminoglycans; Heparin; Heparitin Sulfate; Humans

Diabetes is a widespread disease with many clinical pathologies. Despite numerous pharmaceutical strategies for treatment, the incidence of diabetes continues to increase. Hyperglycemia, observed in diabetes, causes endothelial injury resulting in microvascular and macrovascular complications such as nephropathy, retinopathy, neuropathy, and increased atherosclerosis.. Proteoglycans are chemically diverse macromolecules consisting of a protein core with glycosaminoglycans (GAGs) attached. Heparan sulfate proteoglycans are important compounds found on the endothelial cell membrane and in the extracellular matrix, which play an important role in growth regulation and serve as a reservoir for cytokines and other bioactive molecules. Endothelial cells are altered in hyperglycemia by a reduction in heparan sulfate and upregulation and secretion of heparanase, an enzyme that degrades heparan sulfate GAGs on proteoglycans. Reactive oxygen species, increased in diabetes, also destroy GAGs.. Preservation of heparan sulfate proteoglycans on endothelial cells may be a strategy to prevent angiopathy associated with diabetes. The use of GAGs and GAG-like compounds may increase endothelial heparan sulfate and prevent an increase in the heparanase enzyme.. Elucidating the mechanisms of GAG depletion and its significance in endothelial health may help to further understand, prevent, and treat cardiovascular complications associated with diabetes. Further studies examining the role of GAGs and GAG-like compounds in maintaining endothelial health, including their effect on heparanase, will determine the feasibility of these compounds in diabetes treatment. Preservation of heparan sulfate by decreasing heparanase may have important implications not only in diabetes, but also in cardiovascular disease and tumor biology.

Topics: Animals; Diabetes Complications; Diabetes Mellitus; Endothelial Cells; Glycosaminoglycans; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Hyperglycemia

Topics: Atherosclerosis; Cell Adhesion; Cell Movement; Diabetes Mellitus; Extracellular Matrix; Gene Expression Regulation; Glucuronidase; Heparitin Sulfate; Humans; Inflammation; Models, Molecular; Protein Multimerization; Signal Transduction; Substrate Specificity

Insulin-dependent diabetic patients with increased urinary albumin excretion are characterized by elevated blood pressure and declining kidney function. In addition, such patients have a high risk of atherosclerotic vascular disease, proliferative retinopathy, and cardiomyopathy, suggesting that albuminuria is a marker of widespread vascular dysfunction. Increased transport of macromolecules across the vascular wall, elevated plasma levels of von Willebrand factor, and impaired fibrinolytic capacity have been demonstrated in albuminuric patients. The cause of this vascular vulnerability in susceptible patients is unknown, but increasing evidence has suggested that loss of the proteoglycan heparan sulfate in the vasculature may explain the widespread nature of the disease. Heparan sulfate is important for the glomerular endothelial cell and basement membrane charge densities, the anticoagulant properties of the vessel wall, and the growth regulation of intimal smooth muscle cells. Recent studies have shown that heparin increases the biosynthesis of heparan sulfate in endothelial cell cultures and prevents the characteristic glomerular basement membrane thickening when given to diabetic rats. Moreover, heparin has been shown to reduce albuminuria in patients with incipient diabetic nephropathy. Although increasing evidence supports the hypothesis that loss of heparan sulfate may play a pathophysiological role in the development of diabetic vascular complications, there are still many unresolved problems. What are the mechanisms of action of glycosaminoglycans at the molecular biology level, and how can we select compounds without anticoagulant activity suitable for long-term use in the prevention and treatment of late diabetic complications?

Topics: Albuminuria; Animals; Basement Membrane; Diabetes Mellitus; Diabetic Angiopathies; Diabetic Nephropathies; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Proteoglycans

Topics: Animals; Anti-Glomerular Basement Membrane Disease; Basement Membrane; Chondroitin Sulfate Proteoglycans; Collagen; Diabetes Mellitus; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Laminin; Nephritis, Hereditary; Protein Conformation; Skin Diseases, Vesiculobullous

Basement membranes contain a number of intrinsic macromolecular components which are unique to these structures and which cooperatively assemble into specific heteropolymeric matrices. Type IV collagen triple helical monomers bind together at their amino-terminal, carboxy-terminal, and lateral domains to form a lattice-like array. Laminin, in a two-step process, binds to itself at its terminal globular domains to form polymers and also binds collagen at two distinct sites along the collagen chain. Heparan sulfate proteoglycan has been found to bind both collagen and laminin, suggesting a reversible crosslinking function. On the basis of the data derived from self-association studies, it is possible to begin considering models for the assembly and structure of these ubiquitous matrices.

Topics: Animals; Basement Membrane; Collagen; Diabetes Mellitus; Heparitin Sulfate; Humans; Laminin; Mice; Models, Biological

Basement membranes support epithelial and endothelial cells, prevent the passage of proteins, and generate histologically distinct compartments in the body. Basement membranes contain a number of components, only some of which have been isolated and characterized. These include type IV collagen, heparan sulfate proteoglycan, laminin, entactin, and fibronectin. Some components, such as bullous pemphigoid antigen and Goodpasture antigen, are present only in specific tissues, such as the skin or the kidneys. Alterations in basement membranes are associated with various diseases. For example, metastatic cells are able to attach to basement membranes and to degrade them. Such interactions with basement membranes underlie the ability of these cells to penetrate tissues and to spread in the body. In diabetes, basement membranes are thickened but are more porous, which is possibly due to a decreased amount of heparan sulfate proteoglycan. Basement membranes are also the site of immunopathologic disorders.

Topics: Autoimmune Diseases; Basement Membrane; Chondroitin Sulfate Proteoglycans; Collagen; Diabetes Mellitus; Glycoproteins; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Neoplasms; Proteoglycans

Basement membranes are complex macromolecular structures which occupy the extracellular space between cells of different histologic types. Biochemically it is composed of Type IV collagen, several noncollagenous glycoproteins including laminin, fibronectin, GP-2 and PYS glycoprotein, and heparan sulfate. Morphologic changes are commonplace in a number of renal diseases. In diabetic glomerular disease, the basement membrane is markedly thickened but the biochemical basis has not been elucidated. In other disease-associated basement membrane changes, altered glycosylation of glycoprotein components has been described. The most important issue is the effect such alterations have on the interaction of basement membrane components and the function of the basement membrane.

Topics: Amino Acids; Animals; Basement Membrane; Collagen; Diabetes Mellitus; Glycoproteins; Heparitin Sulfate; Humans; Kidney Diseases; Neoplasms

The identification and validation of gene-gene interactions is a major challenge in human studies. Here, we explore an approach for studying epistasis in humans using a Drosophila melanogaster model of neonatal diabetes mellitus. Expression of the mutant preproinsulin (hINS(C96Y)) in the eye imaginal disc mimics the human disease: it activates conserved stress-response pathways and leads to cell death (reduction in eye area). Dominant-acting variants in wild-derived inbred lines from the Drosophila Genetics Reference Panel produce a continuous, highly heritable distribution of eye-degeneration phenotypes in a hINS(C96Y) background. A genome-wide association study (GWAS) in 154 sequenced lines identified a sharp peak on chromosome 3L, which mapped to a 400-bp linkage block within an intron of the gene sulfateless (sfl). RNAi knockdown of sfl enhanced the eye-degeneration phenotype in a mutant-hINS-dependent manner. RNAi against two additional genes in the heparan sulfate (HS) biosynthetic pathway (ttv and botv), in which sfl acts, also modified the eye phenotype in a hINS(C96Y)-dependent manner, strongly suggesting a novel link between HS-modified proteins and cellular responses to misfolded proteins. Finally, we evaluated allele-specific expression difference between the two major sfl-intronic haplotypes in heterozygtes. The results showed significant heterogeneity in marker-associated gene expression, thereby leaving the causal mutation(s) and its mechanism unidentified. In conclusion, the ability to create a model of human genetic disease, map a QTL by GWAS to a specific gene, and validate its contribution to disease with available genetic resources and the potential to experimentally link the variant to a molecular mechanism demonstrate the many advantages Drosophila holds in determining the genetic underpinnings of human disease.

Topics: Alleles; Animals; Animals, Genetically Modified; Diabetes Mellitus; Disease Models, Animal; Drosophila melanogaster; Drosophila Proteins; Epistasis, Genetic; Eye; Female; Gene Expression; Gene Knockdown Techniques; Genetic Variation; Genome-Wide Association Study; Heparitin Sulfate; Humans; Introns; Male; Mutation; Phenotype; Proinsulin; Protein Folding; RNA Interference; Sulfotransferases

The Steno hypothesis (Deckert et al. ) states that in diabetes mellitus (DM), changes in vascular heparan sulfate proteoglycan (HSPG) expression are involved in systemic endothelial dysfunction and increased capillary permeability. In diabetes-induced glomerular capillary leakage, loss of HSPG and its side chains has been documented. This study aimed to investigate whether microvascular leakage in diabetic retinopathy (DR) is also associated with altered expression of HSPG in retinal microvessels.. Serial cryosections of post-mortem eyes of 22 subjects with DM and 7 controls were stained with antibodies against the core proteins of the basement membrane HSPGs agrin (Abs Bl31 and JM72) and perlecan (Ab 1948), and four antibodies against heparan sulfate side chains (HS) (Abs JM403, HepSS1, JM13, 3G10). Moreover, we investigated Cynomolgus monkey eyes injected with vascular endothelial growth factor (VEGF)-A, as a model of retinal microvas-cular leakage. The endothelial antigen PAL-E was used to detect microvascular leakage.. In the retina of all controls and DM cases, agrin and perlecan core proteins and HS as recognized by JM403 and 3G10 were expressed in the walls of microvessels. Staining for JM13 was variable between cases, but unrelated to microvascular leakage as determined by PAL-E. Staining for HepSS1 was absent in all human retinal microvessels. In monkey retinas, HSPG staining was identical to that in human retinal tissues, except for the staining for HepSS1, which was found absent in control monkey eyes but which was positive in VEGF-injected eyes.. Increased microvascular permeability in human DR is not associated with changes in expression of the HSPGs studied, whereas high amounts of VEGF may induce increased expression of the HS side chain epitope recognized by HepSS1. These results suggest that the mechanism underlying retinal leakage is different from diabetic glomerular capillary leakage.

Topics: Aged; Aged, 80 and over; Agrin; Animals; Antibody Specificity; Blood-Retinal Barrier; Capillary Permeability; Diabetes Mellitus; Diabetic Retinopathy; Disease Models, Animal; Endothelial Growth Factors; Fluorescent Antibody Technique, Indirect; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Immunoenzyme Techniques; Macaca fascicularis; Middle Aged; Retinal Vessels; Vascular Endothelial Growth Factor A

Heparan sulphate proteoglycan is an important component of the glomerular anionic filtration barrier and its reduced amount in diabetes contributes to glomerular dysfunction. The objective of this study was to determine if there is also an alteration in the sulphation pattern of the diabetic heparan sulphate chains.. The heparan sulphate in the glomerular basement membrane/mesangial matrix from human diabetic and nondiabetic kidneys obtained at autopsy was fragmented by a hydrazine/nitrous acid procedure and after radiolabelling with NaB[3H]4, the disaccharide products were chromatographically resolved and quantified.. Six sulphated disaccharides were identified in both the diabetic and nondiabetic samples and the molar distribution of these was similar, with the notable exception of the iduronic acid-2-O-sulphatectl--> 4glucosamine-3-O-sulphate species which occurred in the diabetic glomeruli in less than half the amount as in the nondiabetic samples (9.0% compared to 18.7% of total sulphated disaccharides, p < 0.005).. 3-O-sulphated glucosamine is a rare constituent of heparan sulphate occurring usually in a glucuronic acidbeta1--> 4glucosamine-3-O-sulphate(+/- 6-O-sulphate) sequence within the antithrombin-binding domain. In the glomerular basement membrane where the 3-O-sulphated glucosamine is present in substantial amounts, however, it occurs exclusively in an iduronic acid-containing sequence. It is likely that the recently discovered 3-O-sulphotransferase variant which specifically acts on the iduronic acidalpha1--> 4glucosamine sequence is decreased in human diabetes and moreover that this unusual disaccharide could be a component of a specific heparan sulphate domain which interacts with bioactive proteins.

Topics: Aged; Aged, 80 and over; Autopsy; Basement Membrane; Diabetes Mellitus; Disaccharides; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Kidney Glomerulus; Middle Aged; Reference Values

Topics: Albuminuria; Animals; Basement Membrane; Capillary Permeability; Diabetes Mellitus; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Kidney Glomerulus; Proteoglycans

Topics: Alzheimer Disease; Basement Membrane; Diabetes Mellitus; Extracellular Matrix; Forecasting; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Molecular Structure; Neoplasms; Proteoglycans; Structure-Activity Relationship

Treatment of human glomerular basement membrane (GBM) with 4 M guanidine HCl resulted in a preferential extraction of noncollagenous components including laminin, fibronectin, entactin, and heparan sulfate proteoglycan, whereas effective solubilization of type IV collagen required exposure to denaturing solvents in the presence of reducing agents. The guanidine HCl-solubilized constituents were identified by immunochemical procedures after resolution by polyacrylamide gel electrophoresis, CL-6B filtration, and DEAE-cellulose chromatography. Two immunologically related heparan sulfate proteoglycans (Mr approximately 350,000 and 210,000) were observed by electrophoresis, with the higher-molecular-weight form being predominant. An examination of the two proteoglycans after heparitinase digestion or chemical deglycosylation indicated that heparan sulfate chains and other carbohydrate units are attached to core proteins with Mr approximately 140,000 and 110,000, respectively. Radioimmunoassays indicated that human diabetic GBM contained significantly lower (P less than .005) amounts of heparan sulfate proteoglycan and laminin with average values that were 30 and 60%, respectively, of nondiabetic controls; the fibronectin content of the diabetic GBM, however, was not significantly different from the normal. These findings, together with previous studies showing increases in GBM collagen, indicate that an alteration in the macromolecular architecture of this basement membrane occurs in diabetes that may be responsible for the filtration defect and the ultimate glomerular occlusion.

Topics: Animals; Basement Membrane; Cattle; Chromatography, DEAE-Cellulose; Chromatography, Gel; Diabetes Mellitus; Electrophoresis, Polyacrylamide Gel; Glycosaminoglycans; Heparitin Sulfate; Humans; Kidney Glomerulus; Laminin; Mice; Mice, Obese; Proteoglycans; Radioimmunoassay

Diabetes mellitus and asthma have many antipodal features. Although both are common disorders, concurrence occurs less often than would be predicted. When co-existence does occur, the cases are generally mild, and effective treatment of one disease frequently exacerbates the other. The hypothesis is advanced that basilar membrane concentrations of heparan sulfate differ in these two diseases and that this difference may account for the antithetical features. An experimental basis for postulating increased concentrations of extracellular heparan sulfate in asthma and diminished concentrations in diabetes is cited. A rationale for tying these differences to the polar activities of cholinergic transmission and atherogenesis in the two diseases is advanced. Diminished heparan sulfate concentrations in diabetes may down-regulate the transmission of vagal impulses to insulin-producing pancreatic cells, and thereby impair both the continued vitality of these cells, and the acetylcholine modulated potentiation of glucose-induced insulin release.

Topics: Arteriosclerosis; Asthma; Diabetes Complications; Diabetes Mellitus; Heparin; Heparitin Sulfate; Humans; Models, Biological; Synaptic Transmission

Topics: Child; Chondroitin Sulfates; Diabetes Mellitus; Glomerulonephritis; Glycosaminoglycans; Heparitin Sulfate; Humans; Mucopolysaccharidoses; Nephritis, Hereditary; Nephrotic Syndrome; Proteinuria

Platelet factor 4, a unique peptide released during platelet aggregation, can bind to natural sulfated glycosaminoglycans from human renal cortex. The glycosaminoglycan isolate contained components sensitive to hyaluronidase, chondroitinase ABC and nitrous acid. Binding was demonstrated by the change in electrophoretic mobility of platelet factor 4 applied in combination with glycosaminoglycan compared to either applied alone. This effect, which occurred at physiologic pH but not at acidic pH or with high ionic strength, was preserved in samples subjected to prior hyaluronidase and chondroitinase digestion. Further demonstration that platelet factor 4 can interact with heparan sulfate anionic sites in the glomerular microvascular matrix was obtained by incubating radiolabeled platelet factor 4 with isolated rat glomeruli, and with purified human and rat glomerular basement membrane, followed by displacement with heparin. Total binding and heparin-released binding were decreased in glomerular basement membrane prepared from diabetic patients and from rats with streptozotocin-diabetes compared to control samples. These findings implicate platelet factor 4 in the pathogenesis of the altered capillary integrity associated with diabetes, and provide novel evidence that heparan sulfate anionic sites in glomerular basement membrane are diminished in human and experimental diabetes.

Topics: Animals; Basement Membrane; Capillaries; Cattle; Diabetes Mellitus; Diabetes Mellitus, Experimental; Glycosaminoglycans; Heparitin Sulfate; Humans; Kidney Cortex; Kidney Glomerulus; Platelet Factor 4; Rats

The serum concentrations of different glycosaminoglycan fractions have been studied in diabetic subjects without evidence of vascular complications and compared with those of age-and sex-matched normal subjects. Electrophoretic analysis of the various glycosaminoglycan fractions showed an increase in hyalunoric acid and heparin, and a decrease in heparan sulfate, chondroitin-4-sulfate and chondroitin-6-sulfate. Furthermore, the levels of glycosylated haemoglobin A1 were positively correlated with those of hyaluronic acid (r = 0.96, p. less than 0.001) and heparin (r = 0.45, p less than 0.01) in the diabetic group. The present data suggest thah a) in diabetics there is a shift in the metabolism of glycosaminoglycans towards a decreased sulfated glycosaminoglycans/hyaluronic acid ratio; and b) long-lasting hyperglycemia is correlated with the disturbances in the metabolism of glycosaminoglycans.

Topics: Adult; Chondroitin Sulfates; Diabetes Mellitus; Female; Glycated Hemoglobin; Glycosaminoglycans; Heparin; Heparitin Sulfate; Humans; Hyaluronic Acid; Male

The glycosaminoglycan (heparan sulfate) component of glomerular basement membranes from human kidneys of diabetic and nondiabetic subjects has been quantitated after isolation from protease digests of the membranes on DEAE-cellulose microcolumns. A significant decrease (P less than 0.005) in the glycosaminoglycan content of diabetic membranes was observed. Heparan sulfate was identified as the predominant glycosaminoglycan in both diabetic and control subjects and the extent of its sulfation appeared to be similar. The reduced level of glycosaminoglycan in the diabetic glomerular basement membrane was accompanied by a significant elevation of hexoses, which are primarily associated with the collagen component, suggesting that a redistribution of basement membrane macromolecules occurs in the diabetic state. Since heparan sulfate has been implicated as a major component of the glomerular anionic filtration barrier, its decreased content in diabetic basement membranes may contribute to the proteinuria observed in this disease.

Topics: Adult; Aged; Basement Membrane; Diabetes Mellitus; Glycosaminoglycans; Heparitin Sulfate; Humans; Kidney Glomerulus; Middle Aged

We have grown the EHS (Engelbreth-Holm, Swarm) tumor in normal and genetically diabetic mice (db/db) and measured some components of basement membrane produced in the tumor. These studies showed similar amounts of total protein in control and diabetic tissue and similar patterns of proteins on SDS gel electrophoresis of extracts of the tissue. Laminin, a basement membrane specific glycoprotein utilized as an attachment factor by epithelial cells, was present in increased amounts in diabetic tissue. In contrast, the amount of BM-1 (heparan sulfate) proteoglycan was reduced. Less 35S-sulfate was incorporated into this proteoglycan, and the proteoglycan, but not its component glycosaminoglycans, was heterogeneous in size. The data indicate that either the synthesis of proteoglycan was decreased or its degradation was increased in diabetic tissue. Since the heparan sulfate proteoglycan serves to block the passage of anionic macromolecules through the basement membrane, decreased levels could account for the increased porosity of diabetic basement membrane. Compensatory synthesis of the basement membrane components to restore normal permeability could account for the thickened basement membranes observed in diabetes.

Topics: Animals; Basement Membrane; Diabetes Mellitus; Enzyme-Linked Immunosorbent Assay; Glycoproteins; Heparitin Sulfate; Laminin; Mice; Mice, Inbred C57BL; Neoplasm Proteins; Neoplasms, Experimental; Proteoglycans; Rodent Diseases

Cultured fibroblasts derived from normal subjects and juvenile diabetics attach in the absence of serum to plastic culture dishes and secrete macromolecules, including collagenous components, hyaluronic acid, and proteoglycans into the medium and onto the plastic surface where they form a microexudate carpet. Most diabetic fibroblasts examined did not spread as well as normal cells during a 4-hr interval after the initial attachment. There were no significant differences between normal and diabetic cells with respect to proline and lysine incorporation and lysine hydroxylation. The percentage glycosylation of hydroxylysine was marginally higher in the media proteins of diabetic cells, but glycosylation in both normal and diabetic cells was elevated over that typically observed in human skin collagen. Collagenous components were estimated to constitute approximately 15-20% of the microexudate carpet fraction in both normal and diabetic cell strains. Diabetic fibroblasts exhibited a marginally lower ratio of heparan sulfate to chondroitin sulfate in the cell surface to matrix microexudate carpet fraction (trypsinate) than did normal fibroblasts. The hyaluronate and chondroitin sulfate contents of this fraction of diabetic cells were not significantly different from those of normal cells.

Topics: Cell Adhesion; Cell Line; Chondroitin Sulfates; Collagen; Diabetes Mellitus; Fibroblasts; Glycosaminoglycans; Heparitin Sulfate; Humans; Lysine; Proline

The incorporation of [35S]sulfate into glycosaminoglycans was studied in cultures of normal and diabetic skin fibroblasts. Heparan sulfate was determined by column chromatography after enzymatic degradation of chondroitin sulfates and dermatan sulfate by chondroitinase ABE. Cultured skin fibroblasts from both insulin-dependent and noninsulin-dependent diabetics were found to have increased proportions of heparan sulfate in the media relative to the other sulfated glycosaminoglycans.

Topics: Adult; Cells, Cultured; Diabetes Mellitus; Fibroblasts; Glycosaminoglycans; Heparitin Sulfate; Humans; Male; Middle Aged; Skin