Effect of pycnogenol on ethanol-related oxidative retinal injury: an experimental study.

OBJECTIVE

We aimed at determining the protective effects of Pycnogenol on ethanol-induced retinotoxicity in an experimental model.

MATERIALS AND

METHODS

30 male Wistar albino rats were randomly divided into three groups: an untreated healthy control (HC group), a group in which only ethanol was daily administered for six weeks (EtOH group), and a group in which ethanol + 40 mg/kg Pycnogenol was daily administered orally for six weeks (PEtOH group). The same volume (0.5 ml) of distilled water as solvent was applied in the same manner to the rats in the HC and EtOH groups. With the rats in the PEtOH and EtOH groups, 32% ethanol at a dose of 5 g/kg was administered by oral gavage one hour after the application of pycnogenol or distilled water. At the end of the experimental period, tissue samples were obtained for biochemical examination of malondialdehyde (MDA) and total glutathione (tGSH) levels, and afterwards, the eyes were removed for histopathological examination.

RESULTS

Histopathological evaluations in the EtOH group showed significant destruction of retinal tissue with marked edema, decomposition and degeneration in layers, polymorphonuclear cell infiltration, dilatation and congestion in blood vessels. However, it was observed that MDA values increased and tGSH values decreased in the EtOH group. In the PEtOH group, MDA values decreased and GSH values increased. Again, degenerative changes were considerably less in this group.

CONCLUSIONS

In the light of biochemical markers and histopathological evaluations, it was observed that ethanol exposure caused a significant degeneration in the retinal tissue. It was found that Pycnogenol administration significantly reduced the destructive effects seen histopathologically. Biochemical results also coincided with other findings. It was concluded that ethanol-induced rethytosis can be prevented to a large extent by Pycnogenol administration.