Antioxidant enzyme activity and MDA level in the rat testis following chronic administration of ghrelin

Abstract

Ghrelin has recently been reported to exert beneficial effects on various oxidative stresses as a result of its antioxidant properties. Therefore, we designed this study to explore the probable antioxidative effects of this peptide in the testis. Twenty-eight male adult Wistar rats were divided into equal control and treatment groups. In the treatment group, 1 nmol of ghrelin was administered as subcutaneous injection for 10 consecutive days or vehicle (physiological saline) to the control rats. The control and treated rats were killed on days 6 and 10 after beginning of ghrelin injection (n = 7 from each group on each day). The testes were taken and measured for antioxidant enzyme activity and malondialdehyde (MDA) content. Glutathione peroxidase activity significantly increased on day 10 in the treated animals compared with the control group (P < 0.05). Although the mean activity of glutathione peroxidase was greater on day 6 in the ghrelin-treated group than in the control animals, it was not statistically significant. There were no significant differences in superoxide dismutase and catalase activities between the groups. However, MDA level decreased by ghrelin treatment on day 10 compared with the control rats (P < 0.05). The results of this study indicate for the first time novel evidences for antioxidant properties of ghrelin in the rat testis.

Protective effect of ghrelin on paracetamol induced acute hepatotoxicity in rats

“…This was attributed to the decreased bioactivation of PCM caused by the ghrelin pretreatment. This result was supported by previous studies showing that ghrelin induced reduction of the increased level of MDA in preadipocyte cell culture (Zwirska-Korczala et al, 2007) testis and ovary of rats (Kheradmand et al, 2009;Kheradmand et al, 2010). Also, our study in agreement with Obay et al (2008) who demonstrated that pretreatment of rats with different doses of ghrelin prevented pentylenetetrazole-induced elevation in lipid peroxidation.…”

“…Ghrelin is secreted primarily from the stomach, but ghrelin transcripts have been found in many other organs, including the liver, kidney, lung, pancreas, hypothalamus and heart, suggesting an endocrine as well as extra-endocrine action of ghrelin (Kojima et al, 1999;Gnanapavan et al, 2002). Many studies have indicated that ghrelin has beneficial effects on gastrointestinal, cardiovascular, reproductive, immune and coagulation systems (Eter et al, 2007;Chang et al, 2004;Işeri et al, 2005;Kheradmand et al, 2009;Yada et al, 2006;Arıcı and Çetin, 2010). Other studies have revealed that ghrelin may be an antioxidant and anti-inflammatory agent.…”

Ghrelin Improves Antioxidant Defense in Blood and Brain in Normobaric Hypoxia in Adult Male Rats

“…39 Kheradmand's studies showed that ghrelin has antioxidant properties in the rat testis and ovary tissues. 40,41 Moreover, one study proposed that ghrelin increases activity of SOD, CAT, GSH-Px in 3T3 L1 preadipocytes. 42 In our study activity of brain GPx, SOD and catalase were not influenced significantly by ghrelin administration.…”

Effect of in ovo ghrelin administration on serum malondialdehyde level in newly-hatched chickens

“…Malondialdehyde (MDA) is the organic compound with the formula CH 2 (CHO) 2 and it is a bio-marker of oxidative stress in an organism and an increase of MDA level demonstrates oxidative stress [16] . Anti-oxidative activity of ghrelin has been reported in numerous studies [12,13,17] . Reports of Işeri et al [17] indicated anti-oxidative activity of ghrelin and its ameliorative ability for alendronate-induced oxidative stress, as MDA comes back to the control level after ghrelin infusion.…”

“…After identification of ghrelin in mammals by Kojima et al [2] so many relative studies were conducted on ghrelin properties. Studies conducted during last decade suggested various specifies and functions for ghrelin, such as GH-releasing [3] , osteogenesis [4,5] , hematopoiesis [6,7] , food intake and energy balance and regulation [8,9] , endocrine/ paracrine roles in pancreas [10,11] , and currently antioxidative effects [12,13] . Peptide structure of chicken ghrelin has 26 amino acids with 54% similarity to rat ghrelin [14] .…”