The effects of 5-fluorouracil on ocular tissues in vitro and in vivo after controlled release from a multifunctional implant.
OBJECTIVE
To evaluate the effects of 5-fluorouracil (5-FU) on ocular cells in vitro and the effects of degradable 5-FU-loaded poly(DL-lactide-co-glycolide; PDLGA) 50:50 implant in the rabbit eye in vivo.


METHODS
Cytotoxicity was assessed with a tetrazolium salt WST-1 cell proliferation/viability test and a lactate dehydrogenase (LDH) leakage test in rabbit corneal stromal fibroblasts (SIRCs), bovine corneal endothelial cells (BCECs), human conjunctival epithelial cells (IOBA-NHCs), human retinal pigment epithelial cells (ARPE-19), and human corneal epithelial cells (HCECs). The 5-FU-loaded PDLGA implants were surgically placed in rabbit eyes with a deep sclerectomy technique and the histopathology of the eyes was examined.


RESULTS
In vitro, 5-FU affected cell proliferation and survival in a time- and dose-dependent manner. In the WST-1 test, adverse effects in serum-free conditions started from 0.0005 mg/mL 5-FU in SIRCS and HCECs, whereas in other cell types, 0.005 mg/mL 5-FU hindered cell proliferation. In serum-free conditions 72-hour 5 mg/mL 5-FU treatment decreased cell viability to 40% in BCECs and to 10% to 15% in other cell types. 5-FU had no or very minor effects on LDH leakage. In vivo, the 5-FU implant showed no signs of toxicity in cornea and retina, whereas in the conjunctival stroma near the implantation site, some inflammatory cells and a marked subepithelial condensation of stromal connective tissue was observed during the postoperative period of 4 weeks.


CONCLUSIONS
5-FU had a broad therapeutic range, and the 5-FU implant showed only minor tissue reactions in conjunctiva at the surgical site. 5-FU is a possible candidate for controlled drug release.
Huhtala
Anne
A
Cell Research Centre, Medical School, University of Tampere, Tampere, Finland. anne.huhtala@uta.fi
Rönkkö
Seppo
S
Teräsvirta
Markku
M
Puustjärvi
Tuomo
T
Sihvola
Roope
R
Vehanen
Katja
K
Laukkanen
Antti
A
Anttila
Johanna
J
Urtti
Arto
A
Pohjonen
Timo
T
Uusitalo
Hannu
H
D000477:Alkylating Agents / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003228:Conjunctiva / Q000187:drug effects / Q000473:pathology; D003315:Cornea / Q000187:drug effects / Q000473:pathology; D003319:Corneal Stroma / Q000187:drug effects / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D004343:Drug Implants; D004728:Endothelium, Corneal / Q000187:drug effects / Q000473:pathology; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D005123:Eye / Q000187:drug effects* / Q000473:pathology; D005347:Fibroblasts / Q000187:drug effects / Q000473:pathology; D005472:Fluorouracil / Q000494:pharmacology*; D006801:Humans; D011098:Polyglactin 910; D011817:Rabbits; D012160:Retina / Q000187:drug effects / Q000473:pathology; D055213:Retinal Pigment Epithelium / Q000187:drug effects / Q000473:pathology; D012599:Sclerostomy; D013997:Time Factors
D000477:Alkylating Agents; D004343:Drug Implants; D011098:Polyglactin 910; D005472:Fluorouracil