Glycine Supplementation Ameliorates Retinal Neuronal Damage in an Experimental Model of Diabetes in Rats: A Light and Electron Microscopic Study

Purpose: To investigate the potential neuroprotective effect of glycine supplementation on the retinal ultrastructure of streptozocin (STZ)-induced diabetic rats. Methods: Adult male Wistar rats weighing 200–250 g (n = 40) were randomly divided into four groups of 10 each: normal group (C), glycine + normal group (G), STZ group (D), and glycine + STZ group (DG). The G and DG groups received glycine (130 mM and 1% w/v) freely in their drinking water seven days after the induction of diabetes for up to 16 weeks. Retinal samples for histopathology were examined using light and electron microscopy. Results: Diabetes-induced histological changes were attenuated in the retinas of rats in the DG group. The ultrastructural alterations produced by experimental diabetes in the inner nuclear layer, outer nuclear layer, and ganglion cell layer were significantly ameliorated by glycine supplementation. Conclusion: Our findings suggest that glycine supplementation effectively attenuates retinal neuronal damage in experimental diabetic rats, and thus may be a potential candidate to protect retinal ultrastructure against diabetes

Antioxidant capacity and phenolic composition of leaves from 10 Bene (<i>Pistacia atlantica</i> subsp. <i>kurdica</i>) genotypes

<div><p>Leaves of 10 Bene genotypes were collected from six provinces (West Azerbaijan, Kurdistan, Kermanshah, Ilam, Hamedan and Lorestan) in Iran. This study was carried out to better characterise the total phenolic and flavonoid contents, antioxidant capacity and phenolic composition, as well as to evaluate the correlation between content of phenolic compounds and antioxidant activity in 10 genotypes of Bene. The antioxidant activity of leaf extracts was measured using different assays: ferric reducing antioxidant power, nitric oxide radical scavenging and 2,2-diphenyl-1-picrylhydrazyl. The results indicated that the antioxidant capacity can be related to total phenolic and flavonoid content, so that among all the genotypes studied here, the highest and the lowest phenolic content and antioxidant activity were observed in B2 and B10 genotypes, respectively. Analysing the phenolic composition using high performance liquid chromatography, caffeic acid, vanillic acid, ferulic acid and sinapic acid were found in all investigated genotypes.</p></div