Dietary selenium addition improves cerebrum and cerebellum impairments induced by methimazole in suckling rats

Abstract

The aim of this study is to investigate the improving effects of selenium (Se) on cerebrum and cerebellum impairments induced by methimazole (MMI) in suckling rats. Animals were randomly divided into four groups of six each: group I served as control which received standard diet; group II received only MMI (250 mg L(-1)(,) orally); group III received both MMI (250 mg L(-1), orally) and Se (0.5 mg kg(-1) of diet); group IV served as a positive control and received Se (0.5 mg kg(-1) of diet) as sodium selenite (Na(2)SeO(3)). Treatments were started from the 14th day of pregnancy until day 14 after delivery. In the MMI-treated group, plasma-free thyroid hormone levels (FT(3) and FT(4)), protein, DNA and RNA contents in cerebrum and cerebellum decreased when compared to control. Co-treatment with Se ameliorated these parameters. In the MMI-treated group, antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) significantly decreased, while malonaldialdehyde (MDA) levels in cerebrum and cerebellum increased. Co-administration of Se through the diet restored these parameters to near normal values. The biochemical modifications are correlated histologically with the abnormal development of an external granular layer, indicating a delay of granular cells migration towards the molecular layer in the MMI-treated group. Our results showed that Se improved cerebrum and cerebellum MMI-induced damages in suckling rats. Moreover, we concluded that Se is an important neuroprotective element that may be used as a dietary supplement against brain impairments.

Effects of Selenium on Axon and Myelin Healing in an Experimental Sciatic Nerve Injury Model

“…It has been shown that selenium plays an important role in the continuation of the physiological functions of the nervous system (such as signal transduction and development) (10). Previous studies have shown that selenium has a neuroprotective role in various experimental pathologies, such as spinal cord injury, cerebral ischemia and neurotoxicity models (11)(12)(13)(14)(15). Similarly, in our previous study, selenium prevented neurotoxicity that was induced by cisplatin in a partial level (16).…”

“…Previous studies conducted with neurotoxic agents have demonstrated the neuroprotective effect of selenium on the central and peripheral nervous systems (8,(13)(14)(15)(16). However, this study was the first to demonstrate that selenium has a neuroprotective effect on peripheral nerve injury in rats.…”

Oxidative damage induced by chromium (VI) in rat erythrocytes: protective effect of selenium

“…The K 2 Cr 2 O 7 dose was selected on the basis of previous studies [43][44][45]. The Se dose (0.5 mg/kg of diet), used in our experiment and in other findings, gave high protection against stress conditions [10]. According to Hotz et al [37], lower doses of Se gave less protection, while higher doses were not much effective.…”

Dietary selenium's protective effects against methylmercury toxicity

“…Selenoproteins contribute to thyroid hormone biosynthesis, antioxidant defense, redox control of thyrocytes, and thyroid hormone metabolism. The pathological consequences associated with hypothyroidism are attributed to antioxidant imbalances, which is why Se supplementation is also recommended for the treatment of hypothyroidism (Ben Amara et al, 2009). Thyroid hormones have important roles in embryogenesis and fetal maturation and regulate many key biochemical reactions, especially protein synthesis and enzymatic activity.…”