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1.
There are numerous reports on the effects of electromagnetic radiation (EMR) in various cellular systems. Melatonin and caffeic acid phenethyl ester (CAPE), a component of honeybee propolis, were recently found to be potent free radical scavengers and antioxidants. Mechanisms of adverse effects of EMR indicate that reactive oxygen species may play a role in the biological effects of this radiation. The present study was carried out to compare the efficacy of the protective effects of melatonin and CAPE against retinal oxidative stress due to long-term exposure to 900 MHz EMR emitting mobile phones. Melatonin and CAPE were administered daily for 60 days to the rats prior to their EMR exposure during our study. Nitric oxide (NO, an oxidant product) levels and malondialdehyde (MDA, an index of lipid peroxidation), were used as markers of retinal oxidative stress in rats following to use of EMR. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in retinal tissue. Retinal levels of NO and MDA increased in EMR exposed rats while both melatonin and CAPE caused a significant reduction in the levels of NO and MDA. Likewise, retinal SOD, GSH-Px and CAT activities decreased in EMR exposed animals while melatonin and CAPE caused a significant increase in the activities of these antioxidant enzymes. Treatment of EMR exposed rats with melatonin or CAPE increased the activities of SOD, GSH-Px and CAT to higher levels than those of control rats. In conclusion, melatonin and CAPE reduce retinal oxidative stress after long-term exposure to 900 MHz emitting mobile phone. Nevertheless, there was no statistically significant difference between the efficacies of these two antioxidants against to EMR induced oxidative stress in rat retina. The difference was in only GSH-Px activity in rat retina. Melatonin stimulated the retinal GSH-Px activity more efficiently than CAPE did.  相似文献   

2.
Aims: Exposure to electromagnetic radiation (EMR) may increase breast cancer risk by inducing oxidative stress and suppressing the production of melatonin. Aim of the present review is to discuss the mechanisms and risk factors of EMR and oxidative stress-induced breast cancer, to summarize the controlled studies evaluating measures for prevention, and to conclude with evidence-based strategies for prevention.

Materials: Review of the relevant literature and results from our recent basic studies, as well as critical analyses of published systematic reviews were obtained from the Pubmed and the Science Citation Index.

Results: It has been proposed that chronic exposure to EMR may increase the risk of breast cancer by suppressing the production of melatonin; this suppression may affect the development of breast cancer either by increasing levels of circulation of estrogen or through over production of free oxygen radicals. Most epidemiological studies have also indicated overall effect of EMR exposure in premenopausal women, particularly for estrogen receptor positive breast tumors. Enhanced voltage-dependent Ca2+ current and impaired inhibitory G-protein function, and derangement of intracellular organelles with a Ca2+ buffering effect, such as endoplasmic reticulum and mitochondria have been also shown to contribute to disturbed Ca2+ signaling in breast cancer.

Conclusion: Melatonin may modulate breast cancer through modulation of enhanced oxidative stress and Ca2+ influx in cell lines. However, there is not enough evidence on increased risk of breast cancer related to EMR exposure.  相似文献   

3.
Abstract

Increasing use of mobile phones in daily life with increasing adverse effects of electromagnetic radiation (EMR), emitted from mobile on some physiological processes, cause many concerns about their effects on human health. Therefore, this work was designed to study the effects of exposure to mobile phone emits 900-MHz EMR on the brain, liver and kidney of male albino rats. Thirty male adult rats were randomly divided into four groups (10 each) as follows: control group (rats without exposure to EMR), exposure group (exposed to 900-MHz EMR for 1?h/d for 60?d) and withdrawal group (exposed to 900-MHz electromagnetic wave for 1?h/d for 60?d then left for 30?d without exposure). EMR emitted from mobile phone led to a significant increase in malondialdehyde (MDA) levels and significant decrease total antioxidant capacity (TAC) levels in brain, liver and kidneys tissues. The sera activity of alanine transaminase (ALT), aspartate aminotransferase (AST), urea, creatinine and corticosterone were significantly increased (p?<?0.05), while serum catecholamines were insignificantly higher in the exposed rats. These alterations were corrected by withdrawal. In conclusion, electromagnetic field emitting from mobile phone might produce impairments in some biochemicals changes and oxidative stress in brain, liver and renal tissue of albino rats. These alterations were corrected by withdrawal.  相似文献   

4.
Electromagnetic radiation (EMR) of cellular phones may affect biological systems by increasing free radicals and changing the antioxidant defense systems of tissues, eventually leading to oxidative stress. Green tea has recently attracted significant attention due to its health benefits in a variety of disorders, ranging from cancer to weight loss. Thus, the aim of the present study was to investigate the effect of EMR (frequency 900 MHz modulated at 217 Hz, power density 0.02 mW/cm2, SAR 1.245 W/kg) on different oxidative stress parameters in the hippocampus and striatum of adult rats. This study also extends to evaluate the therapeutic effect of green tea mega EGCG on the previous parameters in animals exposed to EMR after and during EMR exposure. The experimental animals were divided into four groups: EMR-exposed animals, animals treated with green tea mega EGCG after 2 months of EMR exposure, animals treated with green tea mega EGCG during EMR exposure and control animals. EMR exposure resulted in oxidative stress in the hippocampus and striatum as evident from the disturbances in oxidant and antioxidant parameters. Co-administration of green tea mega EGCG at the beginning of EMR exposure for 2 and 3 months had more beneficial effect against EMR-induced oxidative stress than oral administration of green tea mega EGCG after 2 months of exposure. This recommends the use of green tea before any stressor to attenuate the state of oxidative stress and stimulate the antioxidant mechanism of the brain.  相似文献   

5.
Diquat is a bipyridyl herbicide that has been widely used as a model chemical for in vivo studies of oxidative stress due to its generation of superoxide anions, and cytotoxic effects. There is little information regarding the toxic effects of diquat on the female reproductive system, particularly ovarian function. Thus, we investigated the reproductive toxic effects of diquat on female mice. Chronic exposure to diquat reduced ovary weights, induced ovarian oxidative stress, resulted in granulosa cell apoptosis, and disrupted oocyte developmental competence, as shown by reactive oxygen species (ROS) accumulation, decreased polar body extrusion rates and increased apoptosis-related genes expression. Additionally, after diquat treatment, the numbers of fetal mice and litter sizes were significantly reduced compared to those of control mice. Thus, our results indicated that chronic exposure to diquat induced reproductive toxicity in female mice by promoting the ROS production of gruanousa cells and ooctyes, impairing follicle development, inducing apoptosis, and reducing oocyte quality. In conclusion, our findings indicate that diquat can be used as a potent and efficient chemical for in vivo studies of female reproductive toxicity induced by oxidative stress. Moreover, the findings from this study will further enlarge imitative research investigating the effect of ovarian damage induced by oxidative stress on reproductive performance and possible mechanisms of action in large domestic animals.  相似文献   

6.
The impact of trace elements, especially zinc, selenium, copper, and magnesium, on male fertility has gained great interest and significance. Increased oxidative stress and altered trace element levels are probable etiological factors underlying male reproductive dysfunction and infertility. The present study focused on the evaluation of seminal oxidative markers, such as reactive oxygen species (ROS), malondialdehyde (MDA), and total antioxidant capacity (TAC), and trace element levels in the normozoospermic fertile control group (n = 40) and asthenozoospermic infertile group (n = 30). Semen from infertile men exhibited significantly higher ROS and MDA levels accompanied with significant decline in TAC and trace element (zinc and magnesium) levels. Furthermore, a significant correlation was observed between trace elements and oxidative markers with sperm motility. The current study revealed increased lipid peroxidation and oxidant-reductant imbalance that leads to deterioration of semen quality and male infertility. Thus, oxidative stress and trace elements can be considered important biomarkers of male infertility. Measurement of seminal oxidative stress with conventional seminological parameters must be integrated in fertility assessment from early stages to ensure healthy semen characteristics and fertility in men.  相似文献   

7.
During recent years, an increasing percentage of male infertility has to be attributed to an array of environmental, health and lifestyle factors. Male infertility is likely to be affected by the intense exposure to heat and extreme exposure to pesticides, radiations, radioactivity and other hazardous substances. We are surrounded by several types of ionizing and non-ionizing radiations and both have recognized causative effects on spermatogenesis. Since it is impossible to cover all types of radiation sources and their biological effects under a single title, this review is focusing on radiation deriving from cell phones, laptops, Wi-Fi and microwave ovens, as these are the most common sources of non-ionizing radiations, which may contribute to the cause of infertility by exploring the effect of exposure to radiofrequency radiations on the male fertility pattern. From currently available studies it is clear that radiofrequency electromagnetic fields (RF-EMF) have deleterious effects on sperm parameters (like sperm count, morphology, motility), affects the role of kinases in cellular metabolism and the endocrine system, and produces genotoxicity, genomic instability and oxidative stress. This is followed with protective measures for these radiations and future recommendations. The study concludes that the RF-EMF may induce oxidative stress with an increased level of reactive oxygen species, which may lead to infertility. This has been concluded based on available evidences from in vitro and in vivo studies suggesting that RF-EMF exposure negatively affects sperm quality.  相似文献   

8.
Ma  Yan  Zhu  Mingkun  Miao  Liping  Zhang  Xiaoyun  Dong  Xinyang  Zou  Xiaoting 《Biological trace element research》2018,186(1):185-198
Over the last decade, there has been an increased concern about the health risks from exposure to arsenic at low doses, because of their neurotoxic effects on the developing brain. The exact mechanism underlying arsenic-induced neurotoxicity during sensitive periods of brain development remains unclear, although enhanced oxidative stresses, leading to mitochondrial dysfunctions might be involved. Here, we highlight the generation of reactive oxygen species (ROS) and oxidative stress which leads to mitochondrial dysfunctions and apoptosis in arsenic-induced developmental neurotoxicity. Here, the administration of sodium arsenite at doses of 2 or 4 mg/kg body weight in female rats from gestational to lactational (GD6-PD21) resulted to increased ROS, led to oxidative stress, and increased the apoptosis in the frontal cortex, hippocampus, and corpus striatum of developing rats on PD22, compared to controls. Enhanced levels of ROS were associated with decreased mitochondrial membrane potential and the activity of mitochondrial complexes, and hampered antioxidant levels. Further, neuronal apoptosis, as measured by changes in the expression of pro-apoptotic (Bax, Caspase-3), anti-apoptotic (Bcl2), and stress marker proteins (p-p38, pJNK) in arsenic-exposed rats, was discussed. The severities of changes were found to more persist in the corpus striatum than in other brain regions of arsenic-exposed rats even after the withdrawal of exposure on PD45 as compared to controls. Therefore, our results indicate that perinatal arsenic exposure leads to abrupt changes in ROS, oxidative stress, and mitochondrial functions and that apoptotic factor in different brain regions of rats might contribute to this arsenic-induced developmental neurotoxicity.  相似文献   

9.
Humanin, a mitochondria-derived peptide, has been found to exert variously protective function in many tissues, especially in the nervous tissues. However, relatively limited studies have focused on the role of humanin in the regulation of reproduction. Current observations indicate that humanin plays an important role in regulating the response of the cell to oxidative stress and apoptosis in ovaries and testes via the modulation of several signaling pathways, especially when the body is in an abnormal state. Even so, the detailed mechanism of humanin function needs to be explored urgently. In this passage, we demonstrate how humanin exerts its protective role in female and male reproduction and raise several questions that need further investigations. Given humanin's new frontier for the design of novel therapeutic approaches for male infertility, male contraception, female infertility, and glucose metabolism in polycystic ovary syndrome, it is worthy of further study on its protective effects and clinical applications in reproductive function  相似文献   

10.
Vanadium has been recognized as industrial hazards that adversely affect male reproductive systems of humans and animals. However, less information is available concerning the underlying mechanism in the pathogenesis of male reproductive dysfunction. The present study investigated the possible involvement of oxidative stress to induce oxidative deterioration of testicular functions in adult rats. The results of in vitro and in vivo studies demonstrate that vanadium treatment resulted in a significant dose- and time-dependent increase in the testicular lipid peroxidation, marked inhibition in the level of superoxide dismutase and catalase activities, decreased sperm counts, and substantially inhibited the activities of Delta(5)3beta- and 17beta-hydroxysteroid dehydrogenase as well as serum testosterone level. Histopathological examination revealed inhibition of spermatogenesis and the preferential loss of maturing and elongated spermatids along with increased percent of abnormal sperm. Taken together, the results suggest that an increase in free radical formation relative to loss of antioxidant defense system during vanadium exposure may render testis more susceptible to oxidative damage leading to their functional inactivation. Thus the toxic effects of vanadium are cumulative and that vanadium produced damages in testes are dose- and time-dependent.  相似文献   

11.
Mercury is a toxic and bio-accumulative heavy metal of global concern. While good deals of research have been conducted on the toxic effects of mercury, little is known about the mechanisms involved in the pathogenesis of male reproductive dysfunction induced by mercury. Therefore, the purpose of this study was to assess the effects and underlying mechanisms of chronic mercury exposure at low levels on male reproductive system of rats. Three-month-old male Wistar rats were divided into two groups and treated for 60 days with saline (i.m., Control) and HgCl2 (i.m. 1st dose: 4.6 µg/kg, subsequent doses 0.07 µg/kg/day). We analyzed sperm parameters, hormonal levels and biomarkers of oxidative stress in testis, epididymis, prostate and vas deferens. Mercury treatment decreased daily sperm production, count and motility and increased head and tail morphologic abnormalities. Moreover, mercury treatment decreased luteinizing hormone levels, increased lipid peroxidation on testis and decreased antioxidant enzymes activities (superoxide dismutase and catalase) on reproductive organs. Our data demonstrate that 60-day chronic exposure to low concentrations of HgCl2 impairs sperm quality and promotes hormonal imbalance. The raised oxidative stress seems to be a potential mechanism involved on male reproductive toxicity by mercury.  相似文献   

12.
The present study evaluates the protective effect of α‐lipoic acid (LA) against arsenic‐induced testicular and epididymal oxidative damage in rats. Arsenic caused significant reduction in the reproductive organ weights, serum testosterone levels, testicular daily sperm count, epididymal sperm count, sperm motility, sperm viability, and sperm membrane integrity. Significant reduction in the activity levels of superoxide dismutase, catalase, and glutathione levels with a concomitant increase in the lipid peroxidation and protein carbonyl content in the testis and the cauda epididymis of arsenic‐exposed rats. Arsenic intoxication also enhanced the testicular caspase‐3 mRNA levels, disorganization of testicular and cauda epididymal architecture as well as increased arsenic content in the testis and the cauda epididymis of rats. Arsenic exposure also deteriorated fertility ability in male rats over controls. Conversely, α‐LA negated the testicular and cauda epididymal oxidative stress and restored the male reproductive health in arsenic‐exposed rats.  相似文献   

13.
Caffeic acid phenethyl ester (CAPE), a flavonoid like compound, is one of the major components of honeybee propolis. It has been used in folk medicine for many years in Middle East countries. It was found to be a potent free radical scavenger and antioxidant recently. The aim of this study was to examine long-term applied 900 MHz emitting mobile phone-induced oxidative stress that promotes production of reactive oxygen species (ROS) and, was to investigate the role of CAPE on kidney tissue against the possible electromagnetic radiation (EMR)-induced renal impairment in rats. In particular, the ROS such as superoxide and nitric oxide (NO) may contribute to the pathophysiology of EMR-induced renal impairment. Malondialdehyde (MDA, an index of lipid peroxidation) levels, urinary N-acetyl-β-d-glucosaminidase (NAG, a marker of renal tubular injury) and nitric oxide (NO, an oxidant product) levels were used as markers of oxidative stress-induced renal impairment and the success of CAPE treatment. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in renal tissue were determined to evaluate the changes of antioxidant status. The rats used in the study were randomly grouped (10 each) as follows: i) Control group (without stress and EMR), ii) Sham-operated rats stayed without exposure to EMR (exposure device off), iii) Rats exposed to 900 MHz EMR (EMR group), and iv) A 900 MHz EMR exposed + CAPE treated group (EMR + CAPE group). In the EMR exposed group, while tissue MDA, NO levels and urinary NAG levels increased (p < 0.0001), the activities of SOD, CAT, and GSH-Px in renal tissue were reduced (p < 0.001). CAPE treatment reversed these effects as well (p < 0.0001, p < 0.001 respectively). In conclusion, the increase in NO and MDA levels of renal tissue, and in urinary NAG with the decrease in renal SOD, CAT, GSH-Px activities demonstrate the role of oxidative mechanisms in 900 MHz mobile phone-induced renal tissue damage, and CAPE, via its free radical scavenging and antioxidant properties, ameliorates oxidative renal damage. These results strongly suggest that CAPE exhibits a protective effect on mobile phone-induced and free radical mediated oxidative renal impairment in rats.  相似文献   

14.
Chronic alcoholism leads to infertility in male and female rats, and antioxidant enzymes form the first line against oxidative stress in organisms. In recent years, betaine has shown beneficial effects on various tissues, and this study has attempted to clarify antioxidant and methyl donor properties of betaine in the rat ovary. For this purpose, the sexually matured Sprague-Dawley female rats were divided into Control, Ethanol (EtOH), Betaine, and Betaine?+?EtOH groups. Administration of betaine in Betaine?+?EtOH group significantly increased CAT activity when compared to the other groups (P?<?0.05). GPx activity increased significantly in Betaine and Betaine?+?EtOH groups as compared to controls (P?<?0.05). Interestingly, GPx and CAT activities insignificantly increased (in order compensatory) in EtOH group to suppress oxidative stress. In contrast, SOD activity decreased insignificantly in EtOH group compared to Betaine?+?EtOH and control groups (P?>?0.05). TBARS concentration (as a lipid peroxidation marker) significantly increased in ethanol-treated rats as compared to controls, while total homocysteine concentration significantly decreased in betaine-treated rats in comparison with EtOH group. Regarding to oestrous cycles, ethanol-treated animals had irregular estral cycle and persistent oestrous phase compared to controls and betaine-treated rats. In conclusion, these results demonstrate for the first time the antioxidant and methyl donor properties of betaine in the rat ovary. Thus, betaine might be used as a potential therapy in hyperhomocysteinemia and partial infertility mediated by oxidative stress in females.  相似文献   

15.
Luo Q  Li Z  Huang X  Yan J  Zhang S  Cai YZ 《Life sciences》2006,79(7):613-621
Lycium barbarum, a famous Chinese medicinal herb, has a long history of use as a traditional remedy for male infertility. Polysaccharides are the most important functional constituent in L. barbarum fruits. We systematically investigated the effect of L. barbarum polysaccharides (LBP) on rat testis damage induced by a physical factor (43 degrees C heat exposure), on DNA damage of mouse testicular cells induced by a chemical factor (H2O2), and on sexual behavior and reproductive function of hemicastrated male rats. The results showed that LBP provided a protective effect against the testicular tissue damage induced by heat exposure. When compared with negative control, a suitable concentration of LBP significantly increased testis and epididymis weights, improved superoxide dismutase (SOD) activity, and raised sexual hormone levels in the damaged rat testes. LBP had a dose-dependent protective effect against DNA oxidative damage of mouse testicular cells induced by H2O2. LBP improved the copulatory performance and reproductive function of hemicastrated male rats, such as shortened penis erection latency and mount latency, regulated secretion of sexual hormones and increased hormone levels, raised accessory sexual organ weights, and improved sperm quantity and quality. The present findings support the folk reputation of L. barbarum fruits as an aphrodisiac and fertility-facilitating agent, and provide scientific evidence for a basis for the extensive use of L. barbarum fruits as a traditional remedy for male infertility in China.  相似文献   

16.
This study aimed to evaluate the effects of quinestrol, a synthetic oestrogen homologue with reproductive toxicity, on the secretion of reproductive hormones and antioxidant status in adult male rat. Our results showed that quinestrol exposure significantly decreased the weight of the testis, epididymides, seminal vesicle, and prostate, as well as the sperm counts in the cauda epididymis of rats. Quinestrol significantly reduced the size of seminiferous tubules and the total number of spermatogenic cells. Serum testosterone, follitropin, and lutropin were also significantly reduced in a dose-related manner after quinestrol exposure. Meanwhile, the activity of superoxide dismutase, glutathione peroxidase, and total antioxide capacity significantly decreased, whereas the malondialdehyde and nitric oxide concentrations significantly increased in the testes. These findings revealed that endocrine disorders of reproductive hormones and oxidative stress may be involved in reproductive toxicity induced by quinestrol in adult male rats.  相似文献   

17.
Exposure to mobile phone-induced electromagnetic radiation (EMR) may affect biological systems by increasing free oxygen radicals, apoptosis, and mitochondrial depolarization levels although selenium may modulate the values in cancer. The present study was designed to investigate the effects of 900 MHz radiation on the antioxidant redox system, apoptosis, and mitochondrial depolarization levels in MDA-MB-231 breast cancer cell line. Cultures of the cancer cells were divided into four main groups as controls, selenium, EMR, and EMR?+?selenium. In EMR groups, the cells were exposed to 900 MHz EMR for 1 h (SAR value of the EMR was 0.36?±?0.02 W/kg). In selenium groups, the cells were also incubated with sodium selenite for 1 h before EMR exposure. Then, the following values were analyzed: (a) cell viability, (b) intracellular ROS production, (c) mitochondrial membrane depolarization, (d) cell apoptosis, and (e) caspase-3 and caspase-9 values. Selenium suppressed EMR-induced oxidative cell damage and cell viability (MTT) through a reduction of oxidative stress and restoring mitochondrial membrane potential. Additionally, selenium indicated anti-apoptotic effects, as demonstrated by plate reader analyses of apoptosis levels and caspase-3 and caspase-9 values. In conclusion, 900 MHz EMR appears to induce apoptosis effects through oxidative stress and mitochondrial depolarization although incubation of selenium seems to counteract the effects on apoptosis and oxidative stress.  相似文献   

18.
ABSTRACT: Oxidative stress (OS), a state characterized by an imbalance between pro-oxidant molecules including reactive oxygen and nitrogen species, and antioxidant defenses, has been identified to play a key role in the pathogenesis of subfertility in both males and females. The adverse effects of OS on sperm quality and functions have been well documented. In females, on the other hand, the impact of OS on oocytes and reproductive functions remains unclear. This imbalance between pro-oxidants and antioxidants can lead to a number of reproductive diseases such as endometriosis, polycystic ovary syndrome (PCOS), and unexplained infertility. Pregnancy complications such as spontaneous abortion, recurrent pregnancy loss, and preeclampsia, can also develop in response to OS. Studies have shown that extremes of body weight and lifestyle factors such as cigarette smoking, alcohol use, and recreational drug use can promote excess free radical production, which could affect fertility. Exposures to environmental pollutants are of increasing concern, as they too have been found to trigger oxidative states, possibly contributing to female infertility. This article will review the currently available literature on the roles of reactive species and OS in both normal and abnormal reproductive physiological processes. Antioxidant supplementation may be effective in controlling the production of ROS and continues to be explored as a potential strategy to overcome reproductive disorders associated with infertility. However, investigations conducted to date have been through animal or in vitro studies, which have produced largely conflicting results. The impact of OS on assisted reproductive techniques (ART) will be addressed, in addition to the possible benefits of antioxidant supplementation of ART culture media to increase the likelihood for ART success. Future randomized controlled clinical trials on humans are necessary to elucidate the precise mechanisms through which OS affects female reproductive abilities, and will facilitate further explorations of the possible benefits of antioxidants to treat infertility.  相似文献   

19.
20.
Polychlorinated biphenyls (PCBs) exposure produces neurodegeneration and induces oxidative stress. Neuroprotective role of quercetin, on PCBs induced apoptosis in hippocampus has not yet been studied. The present study is focused to see whether quercetin supplementation precludes against PCBs induced oxidative stress and hippocampal apoptosis. The results have shown that quercetin at 50 mg/kg bwt/30 days has protected oxidative stress in hippocampus of adult male rats. Quercetin, a free radical scavenger decreased the levels of oxidative stress markers in the hippocampus of simultaneous PCB+quercetin treated rats. The pro-apoptotic and anti-apoptotic molecules such as Bad, Bid, Bax and Bcl2 were altered in the hippocampus of experimental animals. PCBs increased the DNA damage and induced neurodegeneration were assessed by histological studies. PCB induced ROS may be linked to increased hippocampal neuronal apoptosis. Quercetin supplementation decreased the neuronal damage and scavenged the free radicals induced by PCBs and protects PCBs induced apoptosis and oxidative stress.  相似文献   

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