Brazilian Green Propolis Protects against Retinal Damage In Vitro and In Vivo

Abstract

Propolis, a honeybee product, has gained popularity as a food and alternative medicine. Its constituents have been shown to exert pharmacological (anticancer, antimicrobial and anti-inflammatory) effects. We investigated whether Brazilian green propolis exerts neuroprotective effects in the retina in vitro and/or in vivo. In vitro, retinal damage was induced by 24 h hydrogen peroxide (H2O2) exposure, and cell viability was measured by Hoechst 33342 and YO-PRO-1 staining or by a resazurin–reduction assay. Propolis inhibited the neurotoxicity and apoptosis induced in cultured retinal ganglion cells (RGC-5, a rat ganglion cell line transformed using E1A virus) by 24 h H2O2 exposure. Propolis also inhibited the neurotoxicity induced in RGC-5 cultures by staurosporine. Regarding the possible underlying mechanism, in pig retina homogenates propolis protected against oxidative stress (lipid peroxidation), as also did trolox (water-soluble vitamin E). In mice in vivo, propolis (100 mg kg−1; intraperitoneally administered four times) reduced the retinal damage (decrease in retinal ganglion cells and in thickness of inner plexiform layer) induced by intravitreal in vivo N-methyl-d-aspartate injection. These findings indicate that Brazilian green propolis has neuroprotective effects against retinal damage both in vitro and in vivo, and that a propolis-induced inhibition of oxidative stress may be partly responsible for these neuroprotective effects.

Anti-inflammatory and ultrastructural effects of Turkish propolis in a rat model of endotoxin-induced uveitis

“…The protective and pharmacological effects of propolis on retinal damage have previously been examined in vitro and in vivo [27,28], but these studies did not include electron microscopic examinations. However, Sande et al identified disorganization of photoreceptor outer segments and significant alterations of cell structure, including expanded intracellular spaces containing dense bodies and membranous debris, 24 h and 8 days after injection of hamsters with LPS.…”

Própolis e Segurança Alimentar

“…A própolis verde, encontrada no Brasil na região de Minas Gerais é rica em terpenóides e derivados prenilados do ácido cumárico [3] . Pioneiramente, Alencar et al [16] e Silva et al [40] estudaram a própolis vermelha produzida na região de mangue do Estado de Alagoas, baseandose principalmente na sua composição química rica em isoflavonóides e alta atividade antimicrobiana e classificaram como um novo tipo de própolis brasileira (13 º tipo).…”

“…As abelhas usam essa resina para vedar suas colmeias, protegendo-as assim, de insetos e microorganismos invasores [2] . Mais recentemente, a própolis tem sido utilizada no tratamento de várias doenças por parcela da população de países como Japão, Brasil, Estados Unidos e Europa, bem como, tem sido frequente a utilização como ingrediente em produtos cosméticos [3] . Estudos relatam que a própolis tem uma grande variedade de atividades biológicas tais como a antimicrobiana, antiinflamatória, antioxidante e antitumoral [4][5][6] .…”

Edible Seaweed, Eisenia bicyclis, Protects Retinal Ganglion Cells Death Caused by Oxidative Stress

“…After anesthesis with a Zoletil (1.6 μg/g, Verbac Laboratories 06515, France) and Rompun (0.05 μl/g, Bayer) mixture, retinal damage was induced by an injection (2 μl/eye) of NMDA (2.5 mM dissolved in 0.01 M PBS) to the left eye using 30 gauge of Hamilton syringe (Inokuchi et al 2006). One drop of 0.5 % moxifloxacin ophthalmic solution (Alcon Laboratories Inc., Fort Worth, USA) was applied topically to the treated eye immediately after the intravitreous injection.…”