The lens of the eye as a focusing device and its response to stress
Section snippets
Introduction—vertebrate eye development and optical function
In a typical terrestrial eye both the cornea and lens are responsible for focusing an image on to the retina. Both structures have the same basic problem: how to maintain adequate physiological conditions for living tissue, while at the same time providing the image quality of a good optical device? Thus, the cellular physiology of the lens and the cornea include metabolic processes adequate for non-vascular tissue, while anatomically, both the lens and the cornea exhibit adaptations designed
Lens focal properties and lens stress
The review which follows describes recent research involving the in vitro study of the lens in relation to several different areas of lens research. Lens optical changes measured are compared and correlated to change in lens suture anatomy, lens mitochondrial function and morphology and the function of lens heat shock proteins. In addition, lens spherical aberration is evaluated as a function of accommodation. The common feature to this body of work is in the use of an in vitro approach that
Lens focus during mechanical stress (accommodation)
Previous attempts to directly measure the optical properties of the lens during accommodation have been thwarted by its location in the eye; measurements have been made indirectly, usually through the cornea (Glasser et al., 1995), or direct measurements have been made at the cost of the altering the natural physiology of accommodation or the apparatus of the eye itself (Glasser et al., 1995; Glasser and Campbell, 1998). The closest technique to approximating the in vivo condition has been to
Lens mitochondria
A novel recent study, using confocal microscopy, was undertaken to image the movement of the mitochondria-specific dye tetramethylrhodamine ethyl ester (TMRE) in the epithelium and superficial cortex of whole live bovine lenses (Bantseev and Sivak, 2005). The movement of TMRE fluorescence was acquired with a Zeiss 510 (configuration META 18) confocal laser scanning microscope for 10–15 min using 488 nm argon laser excitation and 505 nm Long Pass emission filter settings. The uncoupler of the
Acknowledgements
The authors’ research, described in the review, was supported by the Natural Sciences and Research Council of Canada, the Canadian Foundation for Innovation and Bausch & Lomb, Rochester, New York.
References (173)
- et al.
Structural evidence of human nuclear fiber compaction as a function of ageing and cataractogenesis
Exp. Eye Res.
(2001) - et al.
Optical function and mitochondrial metabolic properties in damage and recovery of bovine lens after in vitro carbonyl cyanide m-chlorophenylhydrazone treatment
Mitochondrion
(2003) - et al.
Effect of hyperbaric oxygen on guinea pig lens optical quality and on the refractive state of the eye
Exp. Eye Res.
(2004) Lens organelle degradation
Exp. Eye Res.
(2002)Behavior of mitochondria in the living cell
Int. Rev. Cytol.
(1990)- et al.
The heat-inducible zebrafish hsp70 gene is expressed during normal lens development under non-stress conditions
Mech. Dev.
(2002) - et al.
Unfolding retinal dystrophies: a role for molecular chaperones
Trends. Mol. Med.
(2001) - et al.
Monochromatic aberrations and myopia
Vision Res.
(1995) - et al.
The internal structure of mitochondria
TIBS
(2000) - et al.
Presbyopia and the optical changes in the human crystalline lens with age
Vision Res.
(1998)
In vitro changes in back vertex distance of chick and pigeon lenses: species differences and the effects of aging
Vision Res.
The mechanism of lenticular accommodation in chicks
Vision Res.
A dynamic relationship between myopia and blur-driven accommodation in school-aged children
Vision Res.
The small heat-shock protein, alphaB-crystallin, has a variable quaternary structure
J. Mol. Biol.
Deamidation and disulfide bonding in human lens gamma-crystallins
Exp. Eye Res.
Viewing molecular mechanisms of ageing through a lens
Ageing Res. Rev.
Structural proteins of the mammalian lens: a review with emphasis on changes in development, aging and cataract
Exp. Eye Res.
The function of alpha-crystallin in vision
Semin. Cell Dev. Biol.
Alpha-crystallin
Exp. Eye Res.
The interrelationship of lens anatomy and optical quality II Primate lenses
Exp. Eye Res.
The relationship between rabbit lens optical quality and sutural anatomy after vitrectomy
Exp. Eye Res.
The maturation of the lens cell: a morphologic study
Exp. Eye Res.
Age-related changes in human lens crystallins identified by two-dimensional electrophoresis and mass spectrometry
Exp. Eye Res.
Constant light produces severe corneal flattening and hyperopia in chickens
Vision Res.
Microtubule configuration and membranous vesicle transport in elongating fiber cells of the rat lens
Exp. Eye Res.
Cold cataract formation in fish lenses
Exp. Eye Res.
Age-related changes in human lens crystallins identified by HPLC and mass spectrometry
Exp. Eye Res.
Longitudinal chromatic aberration of the vertebrate eye
Vision Res.
The structural differences between bovine lens alphaA- and alphaB-crystallin
Eur. J. Biochem.
Heat shock proteins of chicken lens
J. Cell Biochem.
A heat shock transcription factor like protein in the nuclear matrix compartment of the tissue cultured mammalian lens epithelial cell
J. Cell Biochem.
Heat shock proteins of adult and embryonic human ocular lenses
J. Cell Biochem.
Cell kinetic status of mouse lens epithelial cells lacking alphaA- and alphaB-crystallin
Mol. Cell Biochem.
Mitochondria are associated with microtubules and not with intermediate filaments in cultured fibroblasts
Proc. Natl. Acad. Sci. USA
Laser scanning analysis of cold cataract in young and old bovine lenses
Mol. Vis.
Hsp70 in bovine lenses during temperature stress
Mol. Vis.
Mitochondria of rat lenses: distribution near and at the sutures
Curr. Eye Res.
Mechanisms of ocular toxicity using the in vitro bovine lens and sodium dodecyl sulfate as a chemical model
Toxicol. Sci.
Optical properties, mitochondria and sutures of lenses of fishes: a comparative study of nine species
Can. J. Zool.
Confocal laser scanning microscopy imaging of dynamic TMRE movement in the mitochondria of epithelial and superficial cortical fiber cells of bovine lenses
Mol. Vis.
Chaperone activity of cytosolic small heat shock proteins from wheat
Eur. J. Biochem.
Mitochondrial dynamics in differentiating fiber cells of the mammalian lens
Curr. Eye Res.
Coincident loss of mitochondria and nuclei during lens fiber cell differentiation
Dev. Dyn.
Molecular architecture of the lens fiber cell basal membrane complex
J. Cell Sci.
Microtubule-associated movement of mitochondria and small particles in Acanthamoeba castellanii
Cell Motil. Cytoskeleton
Axial chromatic aberration of the human eye
J. Opt. Soc. Am.
The eye as an optical system. Visual optics and the optical space sense
The Eye
Small angle light scattering studies on xylose cataract formation in bovine lenses
Invest. Ophthalmol.
Thermal analysis of cold cataract formation
Lens Res.
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2017, Experimental Eye ResearchCitation Excerpt :the simple (line) sutures of frogs and rabbits, the Y-sutures of most mammals, and the star sutures of humans (Kuszak et al., 2004a, 2004b). The differences may arise from the constraints of lens growth (Kuszak et al., 2004a), the need to precisely position the refractive discontinuities generated by sutures in respect to the retina (Banh et al., 2006), the ability of the suture to facilitate the alterations in lens shape necessary for accommodation (Kuszak et al., 2006), and physiological considerations such as the need for fluid flow within the lens (Vaghefi et al., 2012). Notably, while it is apparent that the hallmark of lens fiber cell differentiation is dramatic reorganization of cell shape from a cuboidal lens epithelial cell to the structurally complex fiber cell, our understanding of the molecular mechanisms underlying this lag far behind that for other critical aspects of fiber cell differentiation including the identity of the key transcription and growth factors critical for the process (Kawauchi et al., 1999; Lovicu et al., 2011; Nishiguchi et al., 1998; Wigle et al., 1999), the terminal exit of lens fibers from the cell cycle (Griep, 2006), the onset of crystallin expression (Cvekl et al., 2015), and the establishment of the lens circulation (Gao et al., 2011; Mathias et al., 2010).
Intact and N- or C-terminal end truncated AQP0 function as open water channels and cell-to-cell adhesion proteins: End truncation could be a prelude for adjusting the refractive index of the lens to prevent spherical aberration
2014, Biochimica et Biophysica Acta - General SubjectsCitation Excerpt :The human lens is uniquely designed to maintain homeostasis and transparency for several decades of life to project a sharp image of objects on the retina. In order to properly focus through a process of accommodation, the constantly growing lens gradually increases the refractive index of the fiber cells toward the center in a continuous gradient [3]. The refractive index of the human lens varies from ~ 1.386 in the less dense outer fiber cells up to ~ 1.406 in more dense central fiber cell layers.
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2013, Biochimica et Biophysica Acta - Molecular Basis of DiseaseCitation Excerpt :The human ocular lens is an avascular transparent tissue with sophisticated optical properties to focus light on the retina, thus allowing the retina to convert the incoming light to neural signals. The optical properties are achieved by the honeycomb-like three-dimensional architecture of the lens fiber cells, the highly differentiated fiber cells, the programmed degradation of the intracellular organelles to avoid light scattering, the expression of the lens-specific genes and the high cytosolic protein concentrations to reach a high refractive index [1–5]. In human lens, the bulk of the soluble proteins in the cytoplasm are crystallins, which are composed of three classes according to their sizes separated by size-exclusion column: α-, β- and γ-crystallin [6,7].