Effects of anti-VEGF agents on rat retinal Müller glial cells

[摘要] Purpose: To evaluate the effects of ananti-rat vascular endothelial growth factor antibody (ARVA) andbevacizumab (Avastin) on rat retinal Müller glial cells (RMGCs) in vivoand in vitro. Methods: Rat RMGCs were identified andcultivated, and were then treated with bevacizumab (0.1, 0.25, and 1mg/ml), ARVA (0.1, 0.5, and 1 µg/ml), or 1 mg/ml of rat immunoglobulinG (IgG) for 12, 24, 48, and 72 h. The numbers of viable RMGCs weredetermined using a trypan blue dye exclusion assay and a methylthiazolyl tetrazolium colorimetric assay. In the in vivo study, therats received intravitreal injections of 5 µl bevacizumab (3.75 mg/ml),ARVA (15 µg/ml), and rat IgG (1 mg/ml). The electroretinogram wasrecorded. Seven days after the injections, histopathologic changes andglial fibrillary acidic protein expression of RMGCs in the retina wereanalyzed by immunohistochemistry with hematoxylin-eosin and fluorescentstaining. Results: After exposure to bevacizumabat various concentrations for various periods of time, the stained cellnumbers and optical density values of mitochondrial dehydrogenaseactivity of RMGCs had no significant differences (p>0.05) from thoseof the control group and IgG medium. In the stained cells, ARVAdemonstrated a dose-dependent increase. Compared with those treated for12 and 24 h, the increase of stained cells treated with 0.5 and 1 µg/mlARVA at 48 and 72 h was very significant (p<0.01). The opticaldensities of RMGCs exposed to 0.5 and 1 µg/ml of ARVA at 48 and 72 hwere significantly lower than cells exposed to a fresh culture medium(p<0.01). The histology of both treated and control eyes afterintravitreal injection was similar and showed no anatomic signs oftoxicity. There were no obvious glial fibrillary acidic proteinupregulations of RMGCs in all groups. The scotopic electroretinogramresponses to flashes of light in the control and treated eyes hadsimilar b-wave amplitudes. Conclusions: Intravitreal bevacizumaband ARVA had no short-term, direct retinal toxicity in rats.Bevacizumab exerts no inhibition on rat RMGCs, while ARVA at higherdoses (over 0.5 µg/ml) may be harmful to the growth of RMGCs.

[学科分类] 生物化学/生物物理