The Antifibrotic Effects of alpha-Tocotrienols in Primary Cultured Orbital Fibroblasts from Thyroid-Associated Ophthalmopathy Patients

ABSTRACT

PURPOSE: To evaluate the antiproliferative and antifibrotic effects of alpha-tocotrienols in primary cultured orbital fibroblasts from thyroid-associated ophthalmopathy (TAO) patients. METHODS: Orbital fibroblasts were cultured (5 eyes from TAO patients, 5 eyes from normal patients) and classified into a control group, alpha-tocotrienol group and alpha-tocopherol group. The cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The proliferation of orbital fibroblasts was measured using the Click-iT(TM) assay. The collagen production of the control and alpha-tocotrienol groups was measured using a hydroxyproline assay. RESULTS: The alpha-tocotrienol and alpha-tocopherol groups showed no cytotoxicity up to 150 microm in orbital fibroblasts from TAO and normal patients. The proliferation of orbital fibroblasts from TAO and normal patients was significantly inhibited with alpha-tocotrienol at 80 microm and 120 microm. The collagen production of orbital fibroblasts from TAO patients was significantly inhibited with alpha-tocotrienol at 120 microm. CONCLUSIONS: The results from the present study indicate that non-toxic concentrations of alpha-tocotrienol have significant antiproliferative and antifibrotic effects on orbital fibroblasts from TAO patients.