Abstract
Abstract: :
Purpose: To verify whether the extract of saffron (Crocus sativus L.) supplemented with the diet, counteracts the effects of continuous light exposure in albino rat retina.Methods: Two experimental groups, control and treated Sprague Dowley rats were used. 1mg of saffron extracts /Kg/die (obtained by Peltuinum Company from L’Aquila) was supplemented for variable time (from two days to six weeks). Animals were exposed at bright continuous light (BCL intensity 1000 lux) for 24 hours. fERG was recorded in control and treated rats before and a week after light exposure, amplitude and latency of a and b waves have been analysed. At the end of the second recording session the animals were sacrified and the retinae were quickly removed, fixed, cryosectioned and labelled to analyse the thickness of the ONL and the activation of self–protective mechanisms. In a second series of experiments rats were sacrified at the end of light exposure and the amount of apoptotic figures in the ONL was assessed by terminal transferase–mediated deoxyuridine triphosphate (d–UTP) –biotin nick–end labeling (TUNEL). BCL induced the DNA fragmentation, characteristic of dying cells, almost exclusively in the photoreceptor layer. The rate of photoreceptor death induced by BCL is expressed as the frequency of TUNEL+ profiles/mm. Results: The photoreceptor layers was pretty much preserved in treated animals as it was the fERG response. In addition the rate of photoreceptor death induced by BCL appeared drastically reduced in treated animals. No activation of self–protective mechanisms was detected. Conclusions: Our results show that saffron might protect photoreceptors from retinal stresses, probably acting as a regulator of cell death program.
Keywords: neuroprotection • photoreceptors • radiation damage: light/UV