title: Effects of hyaluronan viscous materials on cell membrane electrical properties.
abstract: Hyaluronan [hyaluronic acid (HA)] has been implicated in various cellular processes such as proliferation, adhesion, migration, and differentiation. The secondary and tertiary structures of HA give it very important and unique viscoelastic properties. HA-composed materials are currently used intraocularly during ophthalmological surgery to facilitate surgical procedures and prevent tissue damage. To examine the effects of three viscous biomaterials composed of hyaluronan (Healon, IAL, and Biolon) used in ophthalmological surgery, the membrane electrical properties of the erythroleukemic K562 cell line exposed to these materials were investigated. Membrane conductivity, membrane permittivity, and the conductivity of the cytosol were evaluated using dielectric relaxation measurements in the radiofrequency range and fitting the experimental results to the general equations of the Maxwell-Wagner effect. The results demonstrate that while membrane permittivity and the conductivity of the cytosol are not significantly altered, the membrane conductivity of K562 cells exposed to all three biomaterials increases substantially and in a time-dependent manner with respect to untreated cells. These observations seem to indicate that hyaluronan perturbs ionic transport while it does not vary the type, quantity, or distribution of membrane components. In addition, the variations induced by these substances on the cell membrane are not dependent upon the molecular weight or on the biological origin of hyaluronan. These results may aid in elucidating the mechanisms involved in hyaluronan/cell membrane interaction and thus may provide a deeper understanding of the complications related to their use in ophthalmological surgery.
authors.affiliation: Laboratorio di Ultrastrutture, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: M T
authors.initials: MT
authors.lastname: Santini
authors.forename: C
authors.initials: C
authors.lastname: Cametti
authors.forename: G
authors.initials: G
authors.lastname: Formisano
authors.forename: F
authors.initials: F
authors.lastname: Flamma
authors.forename: R
authors.initials: R
authors.lastname: Perilli
mesh_terms: D002462:Cell Membrane / Q000187:drug effects* / Q000502:physiology; D048429:Cell Size; D003600:Cytosol / Q000187:drug effects / Q000502:physiology; D004548:Elasticity; D004553:Electric Conductivity; D006801:Humans; D006820:Hyaluronic Acid / Q000494:pharmacology*; D017136:Ion Transport / Q000187:drug effects; D004915:Leukemia, Erythroblastic, Acute / Q000473:pathology; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000473:pathology; D008153:Lubrication; D008564:Membrane Potentials / Q000187:drug effects; D008970:Molecular Weight; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014783:Viscosity
chemical_list: D006820:Hyaluronic Acid