Retinal Toxicity of Acai Fruit (Euterpe Oleracea) Dye Concentrations in Rabbits: Basic Principles of a New Dye for Chromovitrectomy in Humans

ABSTRACT

Purpose: Evaluate toxicity of acai fruit (Euterpe oleracea) dye concentrations in a rabbit model.

Methods: Rabbits were injected intravitreously with 10%, 25%, and 35% acai dye concentrations. Control eyes received balanced salt solution (BSS). Electroretinogram (ERG), fundus imaging, fluorescein angiography (FA), optical coherence tomography (OCT), and light and transmission electron microscopy (LM/TEM) were performed.

Results: Fundus imaging showed increased vitreous opacity with increased dye concentrations. FA and OCT showed normality with all concentrations. Comparisons between BSS and dye concentrations were analyzed using Kruskal–Wallis and Mood’s median test (p < 0.05). At 24 h, ERGs showed reduced amplitudes from baseline in all eyes. Median b-wave amplitudes nonsignificantly decreased and latency increased with 10% and 25%; findings were significant (p < 0.05) for 35%. LM and TEM showed no abnormalities for 10% and 25%. With 35%, TEM showed ganglion cell edema at 24 h that resolved after 7 days. Vacuolization, multilamellar bodies, and nerve bundle damage occurred at 24 h/7 days in the inner nuclear layer. Mitochondrial cristae disruption occurred in the inner photoreceptor segment at 24 h that decreased by 7 days.

Conclusion: Ten and twenty-five percent concentrations were safe and may improve identification of the posterior hyaloid and internal limiting membrane during chromovitrectomy in humans.

KEYWORDS:

• Acai fruit
• anthocyanins
• chromovitrectomy
• Euterpe oleracea

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Funding

Publication of this article was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP; São Paulo, Brazil), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; Brasília, Brazil), and Pan-American Association of Ophthalmology/Pan-American Ophthalmological Foundation, Paul Kayser Global Award (PAAO/PAOF; Arlington, Texas).

Additional information

Funding

Publication of this article was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP; São Paulo, Brazil), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq; Brasília, Brazil), and Pan-American Association of Ophthalmology/Pan-American Ophthalmological Foundation, Paul Kayser Global Award (PAAO/PAOF; Arlington, Texas).