Study of the effects of oral zinc supplementation on peroxynitrite levels, arginase activity and NO synthase activity in seminal plasma of Iraqi asthenospermic patients

Abstract

BackgroundLow concentrations of nitric oxide (NO) are necessary for the biology and physiology of spermatozoa, but high levels of NO are toxic and have negative effects on sperm functions. Although several studies have considered the relationship between infertility and semen NO concentrations, no study on the effects of asthenospermia treatments such as oral zinc supplementation on concentrations of NO, which are important in fertility, has been reported. Studies have shown that oral zinc supplementation develops sperm count, motility and the physical characteristics of sperm in animals and in some groups of infertile men. The present study was conducted to study the effect of zinc supplementation on the quantitative and qualitative characteristics of semen, along with enzymes of the NO pathway in the seminal plasma of asthenospermic patients.MethodsSemen samples were obtained from 60 fertile and 60 asthenozoospermic infertile men of matched age. The subfertile group was treated with zinc sulfate; each participant took two capsules (220 mg per capsule) per day for 3 months. Semen samples were obtained (before and after zinc sulfate supplementation). After liquefaction of the seminal fluid at room temperature, routine semen analyses were performed. The stable metabolites of NO (nitrite) in seminal plasma were measured by nitrophenol assay. Arginase activity and NO synthase activity were measured spectrophotometrically.ResultsPeroxynitrite levels, arginase activity, NO synthase activity and various sperm parameters were compared among fertile controls and infertile patients (before and after treatment with zinc sulfate). Peroxynitrite levels and NO synthase activity were significantly higher in the infertile patients compared to the fertile group. Conversely, arginase activity was significantly higher in the fertile group than the infertile patients. Peroxynitrite levels, arginase activity and NO synthase activity of the infertile patient were restored to normal values after treatment with zinc sulfate. Volume of semen, progressive sperm motility percentage and total normal sperm count were increased after zinc supplementation.ConclusionsTreatment of asthenospermic patients with zinc supplementation leads to restored peroxynitrite levels, arginase activity and NO synthase activity to normal values and gives a statistically significant improvement of semen parameters compared with controls.Trial registrationClinicalTrials.gov identifier: NCT01684059

Effects of folic acid administration on testicular ischemia/reperfusion injury in rats

“…In the testis, MDA levels elevates in case of the lipid peroxidation which leads to infertility 27 . As observed in this study, spermatozoa mobility and mortality (%) significantly decreased in I/R group (Figures 2-3).…”

Maternal exposure to selenium and cadmium, fetal growth, and placental expression of steroidogenic and apoptotic genes

“…Animal models and in vitro studies have shown that Cd induces preeclampsia-like symptoms, restricts fetal growth (Wang et al, 2014, 2016a), may interfere with placental steroidogenesis (Kawai et al, 2002; Stasenko et al, 2010), inhibits trophoblast proliferation while promoting apoptosis (Wang et al, 2012; Erboga and Kanter, 2016), increases placental oxidative stress (Wang et al, 2012) and interferes with maternal-fetal nutrient transfer across the placenta (Wang et al, 2016a; Mikolić et al, 2015), demonstrating the placenta is a likely target tissue for Cd-associated reproductive toxicity. Indeed, excess ROS generation in the placenta has also been associated with altered placental function and negative pregnancy outcomes (Min et al, 2009; Scifres and Nelson, 2009; Vanderlelie et al, 2005).…”

“…Studies have shown that the tumor necrosis factor super family (TNF-SF) encompasses many potent pro-apoptotic cytokines and their receptors (Zelová and Hošek, 2013), in which some of them have been shown to be perturbed by Cd exposure (Kayama et al, 1995; Kim et al, 2002; Kumar et al, 2016). Cd has also been observed to perturb various steps in progesterone, testosterone, cortisol/cortisone, and estradiol/estrone synthesis (Wang et al, 2014; Kawai et al, 2002; Nagata et al, 2005; Pillai and Gupta, 2005; Pandya et al, 2012; Ronco et al, 2010), and the by-products of these activities present major sources of intracellular ROS, particularly those involved in electron transport at the mitochondrial membrane (Prasad et al, 2014). Based on these observations, we sought to test the hypothesis that maternal Cd and Se exposures during pregnancy might be associated with variations in the placental expression patterns of key genes involved in apoptotic signaling or ROS generation via steroidogenesis, and could be related to fetal growth.…”

A potential role for zinc transporter 7 in testosterone synthesis in mouse Leydig tumor cells

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“…This has been shown to lead to the arrest of spermatogenesis and the impairment of fertilization (10). Indeed, Zn deficiency has been shown to result in oligospermia, which coincides with poor Leydig cell function and lower testosterone concentrations, and these effects may be reversed with Zn supplementation (11,12). Thus, Zn, which is known to be an important cation necessary for the normal functioning of the testes and the regulation of fertility, is now attracting increasing attention from researchers.…”