Hyaluronic acid combined with mannitol to improve protection against free-radical endothelial damage: experimental model.
OBJECTIVE
To evaluate the protective properties of combined sodium hyaluronate 2% and mannitol 0.5% (Visiol) on the corneal endothelium in the presence of oxidative stress induced by hydrogen peroxide (H(2)O(2)).


METHODS
Instituto Oftalmológico de Alicante, Universidad Miguel Hernández, Alicante, Spain.


METHODS
This was an exploratory randomized controlled parallel-group, masked-assessor study of 3 sodium hyaluronate-based ophthalmic viscosurgical devices (OVDs): Visiol, Healon (sodium hyaluronate 1%), and Viscoat (sodium hyaluronate 3%-chondroitin sodium 4%). The OVDs were tested for protective effects on the endothelium following oxidative stress induced by H(2)O(2) at increased concentrations: control (lactated Ringer's solution), 1 mM, 10 mM, and 100 mM. Groups without OVD were used as controls at the same concentrations of peroxide. Each animal received the same treatment in both eyes (10 eyes per group). Endothelial cell lesion was assessed using the Janus green photometry absorbance technique.


RESULTS
At 10 mM peroxide concentration, the value of endothelial cell lesion was significantly lower in the Visiol (16.8%, P=.0056), Healon (22.2%, P=.0302), and Viscoat (21.6%, P=.0336) groups than in the control group (29.4%, no OVD). There was a trend in favor of Visiol to more efficiently reduce cell lesions of the endothelium, than Healon (P=.055) and Viscoat (P=.1013). Values of endothelial cell lesion at peroxide concentrations of 1 mM and 100 mM showed the same trends than those observed at 10 mM.


CONCLUSIONS
All of the OVDs tested efficiently reduced endothelial lesions against free radicals compared with the control group in which no OVD was used. The following sequence for the efficacy of endothelial cell protection was established: Visiol>Viscoat>Healon>no OVD.
Belda
José I
JI
Vissum-Instituto Oftalmológico de Alicante, 03016 Alicante, Spain. ji.beldas@coma.es
Artola
Alberto
A
García-Manzanares
María D
MD
Ferrer
Consuelo
C
Haroun
Hazem E
HE
Hassanein
Ahmed
A
Baeyens
Vincent
V
Munoz
Gonzalo
G
Alió
Jorge L
JL
D000818:Animals; D019610:Cytoprotection / Q000187:drug effects; D004359:Drug Therapy, Combination; D004728:Endothelium, Corneal / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D005609:Free Radicals / Q000633:toxicity; D006820:Hyaluronic Acid / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000633:toxicity; D008353:Mannitol / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects; D011817:Rabbits
D005609:Free Radicals; D008353:Mannitol; D006820:Hyaluronic Acid; D006861:Hydrogen Peroxide