Pericyte adhesion is impaired on extracellular matrix produced by endothelial cells in high hexose concentrations

Beltramo, Elena; Pomero, Fulvio; Allione, Attilio; Dalu, Firass Abu; Ponte, E; Porta, Massimo

doi:10.1007/s00125-001-0761-x

Cited by 45 publications

(31 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Aminoguanidine inhibits the progression of labile adducts to permanent AGEs [19]. The short exposure of endothelial cells to high hexose and to thiamine and aminoguanidine in our work is consistent with the observation that glycation was mediated by intermediate glycolysis metabolites, rather than by direct action of D-glucose and D-galactose and that aminoguanidine and thiamine could inhibit initial stages of glycation [12,23]. The smaller effect of L-glucose (confirmed by BrdU incorporation, but not by cell counts) might support a minor role also for direct glycation and/or osmotic mechanisms.…”

Section: Discussionsupporting

confidence: 90%

“…Augmented synthesis of basement membrane collagen in the retina [26] and of collagen [27], laminin [28] and fibronectin [29] in kidney glomeruli were shown in diabetic rats, while fibronectin immunostaining is increased in the retina of diabetic subjects with background retinopathy [30]. Consistent with our previous observation that pericyte adhesion is not modified by increasing concentrations of laminin, fibronectin or type IV collagen [12], we were also unable to observe an influence on BRP replication at day 7. Decrease of BRP counts on plates pretreated with 50 µg/ml type IV collagen was presumably an artefact, as the cells became more adherent after 7 days than in any other experimental condition.…”

Section: Discussionsupporting

confidence: 86%

“…These results suggest that pericytes seeded on ECM produced by endothelial cells in high glucose replicate with a pattern similar to their initial adhesion rate [12]. As a consequence, reduced BRP counts and BrdU uptake at day 7 could have resulted from similarly reduced adhesion to the different substrates at the time of seeding with a minor number of cells available to start dividing.…”

Section: Discussionmentioning

confidence: 72%

“…We have previously shown that pericyte adhesion is impaired on ECM produced by endothelial cells in high hexose concentrations [12]. The aim of this study was to further investigate if abnormal ECMs produced by endothelial cells cultured in high hexose concentrations influence pericyte viability, i.e.…”

mentioning

confidence: 98%

See 3 more Smart Citations

A study of capillary pericyte viability on extracellular matrix produced by endothelial cells in high glucose

et al. 2003

Self Cite

View full text Add to dashboard Cite

Aims/hypothesis. Thickening of the basement membrane and selective loss of pericytes occur early in diabetic retinopathy. As we showed previously that pericyte adhesion is impaired on extracellular matrix produced by endothelial cells in high hexose concentrations, we aimed to verify if altered adhesion could influence pericyte viability and replication. Methods. Conditioned extracellular matrices were obtained by growing human umbilical vein endothelial cells in media containing 28 mmol/l D-glucose, with or without the inhibitors of protein glycation thiamine or aminoguanidine, and D-galactose or L-glucose up to 28 mmol/l. Having removed the endothelium, bovine retinal pericytes were grown on these matrices and, in separate experiments, on laminin, fibronectin or type IV collagen. Pericyte viability and replication were measured by cell counts and DNA synthesis after 7 days, cell cycle traversal after 2 days and apoptosis after 18 h, 2 days and 7 days.Results. Pericyte counts and DNA synthesis were reduced on matrices produced in high D-glucose and Dgalactose, whilst matrix obtained in L-glucose reduced DNA synthesis but not counts. Both thiamine and aminoguanidine corrected reduced pericyte viability when added to high D-glucose. Cell cycle and apoptosis were not affected by growing pericytes on different conditioned matrices. Laminin, fibronectin and type IV collagen did not modify pericyte replication. Conclusions/interpretations. Reduced pericyte counts could depend on impaired initial adhesion to the extracellular matrix produced by endothelium in high hexose concentrations, rather than impaired replication or viability. Altered cell-matrix interactions might facilitate pericyte dropout in diabetic retinopathy, independently of the effects of high glucose on pericyte replication. [Diabetologia (2003) 46:409-415] Keywords Diabetic retinopathy, extracellular matrix, pericytes, endothelium, glucose, galactose, aminoguanidine, thiamine, glycation. and is observed in other forms of hyperhexosaemia, such as galactose-fed rats, which also develop a diabetic-like retinopathy [3,4]. The evolution of diabetic retinopathy is strongly influenced by qualitative and quantitative changes in the extracellular matrix (ECM) of the capillary basement membrane. In particular, alterations of some ECM components were shown to influence the characteristics of endothelium [5] and ECM-associated growth factors [6], although the mechanisms are still unclear.Endothelium is likely to represent the major contributor to the synthesis of capillary ECM material. In particular, endothelial cells were found to increase their synthesis of type IV collagen and fibronectin Thickening of the basement membrane is an early event in the course of diabetic microangiopathy [1,2]

show abstract

Section: Discussionsupporting

confidence: 90%

Section: Discussionsupporting

confidence: 86%

Section: Discussionmentioning

confidence: 72%

mentioning

confidence: 98%

See 2 more Smart Citations

A study of capillary pericyte viability on extracellular matrix produced by endothelial cells in high glucose

et al. 2003

Self Cite

View full text Add to dashboard Cite

show abstract

“…BRP were obtained from pools of 15 to 20 bovine retinas and characterized by 3G5 fluorescence immunostaining, as described previously [4]. All experiments were repeated using a different pool every time.…”

Section: Methodsmentioning

confidence: 99%

Effects of protein kinase C inhibition and activation on proliferation and apoptosis of bovine retinal pericytes

et al. 2003

Self Cite

View full text Add to dashboard Cite

Aims/hypothesis. Drop-out of capillary pericytes occurs early and selectively in diabetic retinopathy. High glucose concentrations decrease replication and increase apoptosis of cultured pericytes. Since glucose activates protein kinase C, we investigated the effects of modulating this intracellular mediator on replication, cell cycle and apoptosis of cultured bovine retinal pericytes. Methods. Pericytes cultured in 5.6 or 28 mmol/l glucose were exposed to a protein kinase C activator (phorbol 12-myristate 13-acetate) and/or a selective inhibitor of its β2 isoform (LY379196). Cells were counted after 7 days. Proliferation by the tetrazolium to formazan assay and DNA synthesis by 5-bromo-2′-deoxyuridine incorporation were measured at day 4. Cell cycle by flow cytometry and apoptosis by ELISA were assessed at day 2. Results. High glucose reduced pericyte replication and increased apoptosis. Protein kinase C activation increased proliferation, while inhibition of its β2 isoform decreased it. Cell cycle was accelerated by protein kinase C activation and delayed by inhibition. Apoptosis was enhanced by protein kinase C inhibition and reduced by activation. Conclusions/interpretation. Protein kinase C inhibition amplifies the anti-proliferative and pro-apoptotic effects of high glucose on cultured pericytes, whereas stimulation reduces apoptosis and promotes proliferation both in physiological glucose and high glucose. Protein kinase C inhibition, proposed for the treatment of diabetic macular edema and proliferative retinopathy, might accelerate pericyte dropout in earlier stages when these cells are still present in retinal capillaries. [Diabetologia (2003) 46:416-419]

show abstract

Thiamine and benfotiamine prevent apoptosis induced by high glucose‐conditioned extracellular matrix in human retinal pericytes

Beltramo¹,

Nizheradze²,

Berrone³

et al. 2009

Diabetes Metabolism Res

View full text Add to dashboard Cite

Apoptosis is strongly increased in pericytes cultured on ECM produced by endothelium in HG, probably due to impairment of the Bcl-2/Bax ratio. Thiamine and benfotiamine completely revert this effect. This behaviour is therefore completely different from that of bovine pericytes, underlining the importance of establishing species-specific cell models to study the mechanisms of diabetic retinopathy.

show abstract

Pericyte adhesion is impaired on extracellular matrix produced by endothelial cells in high hexose concentrations

Cited by 45 publications

References 9 publications

A study of capillary pericyte viability on extracellular matrix produced by endothelial cells in high glucose

A study of capillary pericyte viability on extracellular matrix produced by endothelial cells in high glucose

Effects of protein kinase C inhibition and activation on proliferation and apoptosis of bovine retinal pericytes

Thiamine and benfotiamine prevent apoptosis induced by high glucose‐conditioned extracellular matrix in human retinal pericytes

Contact Info

Product

Resources

About