Mechanical responsiveness of the endothelial cell of Schlemm's canal: scope, variability and its potential role in controlling aqueous humour outflow

@article{Zhou2011MechanicalRO,
  title={Mechanical responsiveness of the endothelial cell of Schlemm's canal: scope, variability and its potential role in controlling aqueous humour outflow},
  author={Enhua H. Zhou and Ramaswamy Krishnan and W. Daniel Stamer and Kristin M. Perkumas and Kavitha Rajendran and J Nabhan and Q. Lu and Jeffrey J. Fredberg and M Johnson},
  journal={Journal of The Royal Society Interface},
  year={2011},
  volume={9},
  pages={1144 - 1155}
}
Primary open-angle glaucoma is associated with elevated intraocular pressure, which in turn is believed to result from impaired outflow of aqueous humour. Aqueous humour outflow passes mainly through the trabecular meshwork (TM) and then through pores formed in the endothelium of Schlemm's canal (SC), which experiences a basal-to-apical pressure gradient. This gradient dramatically deforms the SC endothelial cell and potentially contributes to the formation of those pores. However, mechanical… 

Figures and Tables from this paper

Altered Mechanics of Schlemm's Canal Endothelial Cells and Trabecular Meshwork in Glaucoma
TLDR
The results show that both SC cell stiffness and that of their substrate can be measured simultaneously in-situ, and computational simulations confirm previous in-vitro measurements.
Biomechanics of Schlemm's canal endothelium and intraocular pressure reduction
Biomechanical regulation of permeability in Schlemm's canal endothelium with respect to glaucoma
TLDR
Pore formation is a mechanosensitive process that allows the inner wall to function as a self-regulating filter by modulating its own porosity in response to local biomechanical cues arising from basal-to-apical filtration across the endothelium.
Altered mechanobiology of Schlemm’s canal endothelial cells in glaucoma
TLDR
It is demonstrated that cells from the canal of Schlemm of glaucomatous eyes have altered gene expression and increased cytoskeletal stiffness that leads to reduced pore formation that positively correlates with elevated subcortical cell stiffness, along with an enhanced sensitivity to the mechanical microenvironment.
Schlemm's canal: the outflow ‘vessel’
TLDR
The present review comprehensively covers the morphology of Schlemm’s canal (SC) and AH pathways, and channelography is presented as a precise method of assessing the conventional drainage pathway and facilitating localization of an uncollapsed collector and aqueous veins.
Targeting Schlemm’s Canal in the Medical Therapy of Glaucoma: Current and Future Considerations
TLDR
Evidence from ongoing research efforts to develop effective antiglaucoma therapies targeting SC suggests that this could become a promising site of future therapeutic interventions.
A Closer Look at Schlemm’s Canal Cell Physiology: Implications for Biomimetics
TLDR
Recent advances in culturing and manipulating Schlemm’s canal cells have elucidated several aspects of their physiology, including ultrastructure, cell-specific marker expression, and biomechanical properties, and implications for engineering a 3D, biomimetic, in vitro model of the Schle mm’S canal endothelium to further advance glaucoma research.
Finite element analysis of the pressure-induced deformation of Schlemm’s canal endothelial cells
TLDR
Finite element modeling and estimates of cell modulus made using atomic force microscopy are used to characterize the pressure-induced deformation of SC cells and to estimate the maximum pressure drop that SC cells can support.
...
...

References

SHOWING 1-10 OF 110 REFERENCES
Young’s modulus of elasticity of Schlemm’s canal endothelial cells
TLDR
The results showed that the upper bound for the effective Young’s modulus of elasticity of the cultured SC cells examined in this study, in central, non-nuclear regions, ranged between 1,007 and 3,053 Pa, which is similar to, although somewhat larger than values that have been measured for other endothelial cell types.
AQUEOUS OUTFLOW CHANNELS IN THE TRABECULAR MESHWORK IN MAN*
  • J. Speakman
  • Biology
    The British journal of ophthalmology
  • 1959
TLDR
The present study of the anatomy of the drainage channels has been made in an attempt to elucidate the nature of the filtration channels adjacent to the canal of Schlemm.
Isolation, culture, and characterization of endothelial cells from Schlemm's canal.
TLDR
Cannulation of SC with gelatin-coated suture material is an effective method for the isolation of human SC cells and provides a cellular model to study the potential role of SC cells in aqueous humor outflow function.
SCANNING ELECTRON MICROSCOPIC STUDIES OF THE TRABECULAR MESHWORK AND THE CANAL OF SCHLEMM ‐ AN ATTEMPT TO LOCALIZE THE MAIN RESISTANCE TO OUTFLOW OF AQUEOUS HUMOR IN MAN
TLDR
Chamber angle tissue from human eyes was investigated with scanning electron microscopy and calculated that if all the observed pores exist in vivo, the resistance to outflow in the paths through the endothelial cells is a small fraction of the total resistance toOutflow.
'What controls aqueous humour outflow resistance?'.
The trabecular meshwork outflow pathways: structural and functional aspects.
  • E. Tamm
  • Biology, Engineering
    Experimental eye research
  • 2009
Human Schlemm's canal cells express the endothelial adherens proteins, VE-cadherin and PECAM-1
TLDR
VE-cadherin and PECAM-1 expression in SC suggests that SC cells are vascular in origin and contain adherens protein likely involved in restricting fluid flow across the inner wall of SC.
...
...