Risultati eccezionali sugli effetti dello Zafferano dell’Aquila Peltuinum nella retina.
13 March 2008 – 12:36 amSaffron Supplement Maintains Morphology and Function after Exposure to Damaging Light in Mammalian Retina
Authors: Rita Maccarone, Stefano Di Marco e Silvia Bisti
From the Department of Science and Biomedical Technology, University of L’Aquila, L’Aquila, Italy; ARC Centre of Excellence in Visual Science, Canberra, Australia; and the Istituto Nazionale Biostrutture e Biosistemi (INBB), Rome, Italy.
PURPOSE. To test whether the saffron extract (Crocus sativus L.) given as a dietary supplement counteracts the effects of continuous light exposure in the albino rat retina.
METHODS. Three experimental groups of Spragueawley rats were used.
Experimental animals were prefed either saffron or carotene (1 mg extract/kg/d) before they were exposed to bright continuous light (BCL) for 24 hours. Flash electroretinograms (fERGs) were recorded in control and treated rats the day before and 1 week after light exposure. At the end of the second recording session, the animals were killed and the retinas were quickly removed, fixed, cryosectioned, and labeled so that the thickness of the outer nuclear layer (ONL) could be analyzed. Changes in protein level and cellular localization of fibroblast growth factor (FGF)2 were determined by Western blot analysis and retinal immunohistochemistry, respectively. In a second series of experiments, rats were killed 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 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-positive profiles per millimeter.
DIET SUPPLEMENTATION
Stigmas of saffron (L’Aquila Saffron; Antica Azienda Agricola Peltui- num, Prata D’Ansidonia, Italy) were dissolved in water to obtain a suspension, and 1 mg/kg was directly offered every day through a syringe. Animals learned easily to suck directly from the tip. A similar procedure was adopted for -carotene (extracted from Dunaliella salina by Norbiotech Chile S.A. la Tirana, Iquique, Chile) dissolved in olive oil; the daily dose was 1 mg/kg.
RESULTS. The photoreceptor layer was largely preserved in saffron-treated animals because it was the fERG response. In addition, the rate of photoreceptor death induced by BCL appeared drastically reduced in treated animals. In carotene prefeeding experiments, morphologic analysis showed preservation of the ONL similar to that obtained with saffron prefeeding, whereas the fERG response was unrecordable. Western blot analysis showed that exposure to light induced a strong upregulation of FGF2 in control and carotene reated rats, but s no change was noted in saffron-treated rats.
CONCLUSIONS. These results show that saffron may protect photoreceptors from retinal stress, maintaining both morphology and function and probably acting as a regulator of programmed cell death.
Fonte: HYPERLINK
http://www.iovs.org/cgi/content/abstract/49/3/1254
