Introduction: Monosodium glutamate is a food additive which acts as preservative or enhancer of palatability. Some studies show some adverse effects of this agent on reproductive system like as structural and functional alterations and reduction of fertility. According to various antioxidant properties of quince leaves and the cytotoxic effects of monosodium glutamate, the aim of  this study was to evaluate the protective effects of quince leaf extract on testicular tissue alterations induced by monosodium glutamate.

Materials & methods: 60 adult rats were divided into six groups: 1) control; 2) monosodium glutamate (30mg/kg i.p.); 3) monosodium glutamate (60mg/kg i.p.); 4) monosodium glutamate (30mg/kg i.p.) + quince leaf extract (500mg/kg p.o.); 5) monosodium glutamate (60mg/kg i.p.) + quince leaf extract (500mg/kg p.o.) and 6) control + quince leaf extract (500mg/kg p.o.). At the end of eight weeks, histomorphometeric and spermatogenic evaluations were done on testicular samples.

Findings: The results showed that, administration of monosodium glutamate lead to structural and functional alteration of testicular tissue such as tubular atrophy and spermatogenic amendments while, use of quince leaf extract can reduce the revealed alterations.

Discussion & conclusions: According to the findings, it is concluded that antioxidant herbs such as quince leaf, can be effective in reducing of structural alterations of testicular tissue induced by monosodium glutamate.