Accepted Manuscript

Title: Oxidative stress of brain and liver is increased by Wi-Fi(2.45 GHz) exposure of rats during pregnancy and thedevelopment of newborns

Author: Omer Celik Mehmet Cemal Kahya MustafaNazıroglu

PII: S0891-0618(15)00074-5DOI: http://dx.doi.org/doi:10.1016/j.jchemneu.2015.10.005Reference: CHENEU 1344

To appear in:

Received date: 22-9-2015Revised date: 15-10-2015Accepted date: 16-10-2015

Please cite this article as: <doi>http://dx.doi.org/10.1016/j.jchemneu.2015.10.005</doi>

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Oxidative stress of brain and liver is increased by Wi-Fi (2.45 GHz) exposure of rats

during pregnancy and the development of newborns

Ömer Çelik1,2, Mehmet Cemal Kahya3, Mustafa Nazıroğlu1,2,

1Neuroscience Research Center, Suleyman Demirel University, Isparta, Turkey 2Department of Biophysics, Medicine Faculty, Suleyman Demirel University, Isparta, Turkey 3Department of Biophysics, Medicine Faculty, Izmir Katip Celebi University, Izmir, Turkey

Corresponding authors Assist. Prof. Dr. Ömer ÇELİK Department of Biophysics, Medicine Faculty, Süleyman Demirel University, Isparta, Turkey Omercelik.vm@gmail.com Prof. Dr. Mustafa NAZIROĞLU Director of Neuroscience Research Center, Medical Faculty, Süleyman Demirel University TR-32260 Isparta- Turkey Tel:+90 246 2113641 Fax:+90 246 2371165 mustafanaziroglu@sdu.edu.tr

List of Abbreviations EMR, electromagnetic radiation GSH, glutathione GSH-Px, glutathione peroxidase LP, lipid peroxidation PUFAs, polyunsaturated fatty acids ROS, reactive oxygen species SAR, specific absorption rate Running Title: Wireless, brain and development of newborn rat

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Abstract

An excessive production of reactive oxygen substances (ROS) and reduced antioxidant

defence systems resulting from electromagnetic radiation (EMR) exposure may lead to

oxidative brain and liver damage and degradation of membranes during pregnancy and

development of rat pups. We aimed to investigate the effects of Wi-Fi-induced EMR on the

brain and liver antioxidant redox systems in the rat during pregnancy and development.

Sixteen pregnant rats and their 48 newborns were equally divided into control and

EMR groups. The EMR groups were exposed to 2.45 GHz EMR (1 hour/day for 5 days/week)

from pregnancy to 3 weeks of age. Brain cortex and liver samples were taken from the

newborns between the first and third weeks. In the EMR groups, lipid peroxidation levels in

the brain and liver were increased following EMR exposure; however, the glutathione

peroxidase (GSH-Px) activity, and vitamin A, vitamin E and -carotene concentrations were

decreased in the brain and liver. Glutathione (GSH) and vitamin C concentrations in the brain

were also lower in the EMR groups than in the controls; however, their concentrations did not

change in the liver.

In conclusion, Wi-Fi-induced oxidative stress in the brain and liver of developing rats

was the result of reduced GSH-Px, GSH and antioxidant vitamin concentrations. Moreover,

the brain seemed to be more sensitive to oxidative injury compared to the liver in the

development of newborns.

Keywords: Brain; Electromagnetic radiation; Glutathione; Liver; Oxidative stress;

Antioxidant vitamins.

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Introduction

There is currently a widespread use of wireless local area network (WLAN) systems (2.45

GHz) being used as an alternative to wired internet access in many areas including

universities, schools, homes and public areas (Nazıroğlu et al. 2013; Dasdag et al. 2015).

Several studies have suggested that biological systems might be sensitive to such forms of

radiation (Otto and von Mühlendahl, 2007; Takahashi et al. 2010; Çetin et al. 2014; Dasdag et

al. 2015). Results of epidemiological (McBride et al. 1999; Burch et al. 2002) and

experimental (Tomruk et al. 2010; Özorak et al. 2013; Çetin et al. 2014) studies have reported

health risks for public exposure to electromagnetic radiation (EMR). These risks need to be

investigated to ensure the safety of women and offspring since these vulnerable individuals

are exposed at the same level of environmental EMR as the general population (Otto and von

Mühlendahl, 2007; Takahashi et al. 2010; Çetin et al. 2014). During a human pregnancy,

EMR exposure may interact with the foetus and result in developmental abnormalities that

may potentially cause foetal death or mutations (Mendonca et al. 2011; Nguyen and

Goodman, 2012). The biological effects of EMR and their consequences are receiving great

interest; however, data on these effects are still scarce and conflicting.

Reactive oxygen substances (ROS) are produced in many physiological functions such

as phagocytic activity and mitochondrial functions. ROS induce oxidative injuries in cellular

biomolecules such as lipids, proteins and nucleic acids (Dasdag et al. 2009; Akdag et al.

2013). The brain consumes the highest amount of oxygen in the human body and has poor

antioxidant levels (Halliwell, 2006). The brain also has high levels of polyunsaturated fatty

acids (PUFAs) that are one of the main targets of ROS (Özmen et al. 2007). These three

factors make the brain more sensitive to oxidative damage. Additionally, EMR is mainly

detoxified in the human liver and it induces hepatoxicity (De and Devasagayam, 2011; Ferk et

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al. 2011). The ROS are controlled and scavenged by enzymatic and non-enzymatic

antioxidants. One of most important enzymatic antioxidants is glutathione peroxidase (GSH-

Px), which converts hydrogen peroxide to water (Nazıroğlu, 2009). Vitamin E is a hydrophilic

molecule that can scavenge several radicals within the cells and plasma (Halliwell, 2006), and

it is likely that vitamins C and E act in a synergistic manner (Frei et al. 1989). Reduced

glutathione (GSH) and β-carotene are hydroxyl radical and singlet oxygen scavengers that

participate in a wide range of cellular functions (Halliwell, 2006; Jiang, 2014). ROS may be

involved in the action of Wi-Fi exposure-induced EMR in the brain and liver of developing

humans and animals. However, this subject needs to be urgently clarified in an experimental

animal model.

EMR absorption rates in various tissues are affected by dielectric properties and organ

conductivity. Whole-body electrical conductivity increases during pregnancy due to an

increased water content, and this makes pregnant women and their foetuses hypersensitive to

EMR (Nazıroğlu et al. 2013). Additionally, Wi-Fi from cell phones and computers are

primarily used near the head and may have harmful effects on the brain. Furthermore, Wi-Fi

exposure induces oxidative stress resulting in decreased antioxidant levels in the brains of

experimental animals (Çetin et al. 2014). However, whether EMR changes oxidative stress in

the brain and liver during offspring development remains unclear; therefore, the need to

address this question has formed the basis of this study.

In a recent study (Çetin et al. 2014), we were unable to observe changes in oxidative

stress values of the brain and liver in 2.45 GHz EMR-exposed newborn rats between the

fourth and sixth weeks following birth because rat brains are developing during the

synaptogenesis period (the first 3 weeks after birth) (Tiwari and Chopra, 2011). Moreover,

reports of EMR exposure on oxidative stress in the brain and liver of rats are conflicting

(Nazıroğlu and Gümral, 2009; Takahashi et al. 2010; Dasdag et al. 2012; Shahin et al. 2013;

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Çetin et al. 2014; Ghazizadeh and Nazıroğlu, 2014; Gürler et al. 2014). The present study was

conducted in rats during pregnancy and newborn development between the first and third

weeks to determine the effects of 2.45 GHz exposure on EMR-induced brain and liver

oxidative injuries.

Materials and methods

Chemicals

N-hexane, reduced glutathione (GSH), malondialdehyde, 1,1,3,3

tetramethoxypropane, KOH, Tris(hydroxymethyl)aminomethane, pyrogallol, all-trans retinol

and α-tocopherol were analytical grade, obtained from Sigma-Aldrich Chemical Inc. (St.

Louis, MO, USA). All solutions, except phosphate buffers, were prepared daily and stored at

+4.0 ˚C. The reagents were allowed to equilibrate at room temperature for at least 30-min

before used for analysis. The phosphate buffers were stable in refrigerator (+4.0 ˚C) for one

month.

Animals

We used 16 Wistar albino pregnant dam rats (age, 12 weeks; weight, 190 ± 21 g) and

their 48 newborns. The rats were housed individually in stainless steel cages in a pathogen-

free environment at 22º ± 2°C, with light exposure from 08.00 to 20.00; the rats were given

free access to water and were fed a commercial diet.

Study groups

The rats were exposed to the EMR radiations during the pregnancy. The 48 newborn

male animals of the rats were selected and randomly divided into two equal groups as follows:

Group A (n=8 pregnant and n=24 newborn): Control rats. The rats exposed to cage stress 60

min/day from pregnancy to 3 weeks old (5 day a week).

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Group B (n=8 pregnant and n=24 newborn): Rats exposed to 2.45 GHz during 60 min/day

from pregnancy to 3 weeks old (Nazıroğlu et al. 2012a).

Control rats were exposed to cage stress without exposure the radiofrequencies.

Pregnancy of the rats was detected presence of sperms in vaginal smear. The condition of the

gestation and any malformation or prenatal death of the offspring did not observe during the

current experiment. After pregnancy, female and male newborn rats were exposed to the EMR

exposures till 3 weeks old. The three weeks of exposure in the newborns were performed in

cage (total body exposure) although mothers received the EMR exposure in a strainer (Figure

1). Control pregnant and offspring rats were kept in the same cage stress condition without

radiation for an additional 3 weeks.

Exposure system and design

The exposure system have been using in our EMR studies routinely and the details of

the 2.45 GHz exposure system have been described in our previous studies (i.e. Nazıroğlu et

al. 2012a; Nazıroğlu et al. 2012b). A generator from Biçer Electronic Co, Sakarya (Turkey),

provided with a half-wave dipole antenna system was used to irradiate the cells with 2.45

GHz radio frequencies with 217 Hz pulses. The electric field density was set at 20 dB and 11

V/m in order to get a 0.1 W/kg whole-body average specific absorption rate (SAR). In a

recent study we observed that oxidative toxic effect of Wi-Fi occurred between 0 and 25 cm

(Çiğ and Nazıroğlu, 2015). Hence, the distance of the antenna from the head of rats for 2.45

GHz exposure was 25 cm (Figure 1). The exposure system was kept a specific room which

was including plastic furniture such as tables and chairs for protecting the rats possible

radiation reflection. Chromium-nickel metals were used for covering walls in order to

protecting the rats from possible outside telemetric exposure. The required electrical field

density (0.1 W/kg whole-body average SAR) for 2.45 GHz exposures, radiation reflection and

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exposure was continuously recorded every 5 minutes using a satellite level meter (EXTECH-

480836, Extech Instruments Corporation, Nashua, NH, USA) as described a previous study

(Çiğ and Nazıroğlu, 2015).

The electromagnetic radiation dose was calculated from the measured electric field

density (V/m). Dielectric permittivity and conductivity values of the rat tissues at certain

frequencies were obtained from the reports of Peyman et al. (2001). The SAR values at the

input 12 μW/cm2 power flux density were calculated using software program. The whole

body SAR values are varied in the 0.01-1.5 W/kg range, representing SAR means values of

0.20 ± 0.06 W/kg for whole body of 2.45 GHz EMR exposures, with a value of 10 V/m at the

closest point in the body.

The rats of control group were placed in the cylindrical restrainer with the radio

frequency source switched off during times similar to those used for irradiation. The control

animals were kept in their cage without any treatment or restraint of any kind.

Anesthesia and preparation of tissue samples

Under ether inhalation anaesthesia, the rats were decapitated, and their brain and liver

samples were removed. After taking the heads from body and the brain cortex and liver

samples were removed. The cortex was dissected out after the brain was split in the mid-

sagittal plane. Following cortex removal, the brain was dissected from the total brain as

described previously (Bütün et al. 2015).

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The brain and liver were weighed, washed twice with cold saline solution, placed into

glass bottles, labelled, and stored in a deep freeze (−85°C) until processing (maximum 3

weeks).After weighing, half of the brain and liver were cut into small pieces using scissors,

and homogenized (5 min at 3000 rpm) in 2 ml volumes (1:5, w/v) of ice-cold Tris-HCl buffer

(50 mM, pH 7.4) using an ultrasonic homogenizer (Bandelin-2070, BANDELIN electronic,

GmbH & Co. KG, Berlin, Germany). All preparation procedures were performed on ice. The

brain and liver homogenate samples were used for measuring the immediate lipid

peroxidation levels and enzyme activities. Antioxidant vitamins were analysed within 3

weeks.

Lipid peroxidation level determinations

Method of Placer et al. (1966) was used for the brain and liver homogenate lipid

peroxidation analyses The quantification of thiobarbituric acid reactive substances was

determined by comparing the absorption to the standard curve of malondialdehyde

equivalents generated by acid catalyzed hydrolysis of 1,1,3,3 tetramethoxypropane. Lipid

peroxidation values in brain and liver samples were expressed as μmol/ g protein.

Reduced glutathione (GSH), glutathione peroxidase (GSH-Px) and protein assays

The GSH content of the brain and liver homogenate was measured at 412 nm using the

method of Sedlak and Lindsay (1968). GSH values in brain and liver samples were expressed

as μmol/ g protein.

GSH-Px activities of the brain and liver homogenate were measured

spectrophotometrically at 37 ºC and 412 nm according to the Lawrence and Burk (1976).

GSH-Px activities in the samples were expressed as International Unit (IU)/ g protein.

The protein content in the brain and liver homogenate was measured by method of

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Lowry et al. (1951) with bovine serum albumin as the standard.

Vitamin analyses

Vitamins A (retinol) (Suzuki and Katoh, 1990) and vitamin E (α-tocopherol) (Desai,

1984) determined in the brain and liver samples via heating and KOH modifications. About

0.5 g of brain and liver samples were saponified by the addition of 0.3 ml 60 percent (w/v in

water) KOH and two ml of one percent (w/v in ethanol) antioxidant pyrogallol, followed by

heating at 70°C for 30 min. After cooling the samples on ice, 2 ml of water and 1 ml of n-

hexane were added and mixed with the samples and then rested for 10 min to allow phase

separation. An aliquot of 0.5 ml of n-hexane extract was taken and vitamin A levels were

measured at 325 nm. Then reactants were added and the absorbance value of hexane was

measured in a spectrophotometer at 535 nm. Calibration was performed using standard

solutions of all-trans retinol and α-tocopherol in hexane.

Folin phenol reagent technique for the estimation of vitamin C as ascorbic acid in

brain and liver homogenate samples was used according to the method of Jagota and Dani

(1982). The absorbance of the samples was measured spectrophotometrically at 760 nm.

Statistical analyses

All results are expressed as means ± standard deviation (SD). To determine the effect

of exposure, data were analyzed using analysis of variance (ANOVA). P-values of less than

0.05 were regarded as significant. Significant values were assessed with least significance test

Mann Whitney U test. Data was analyzed using the SPSS statistical program (version 17.0

software, SPSS Inc. Chicago, IL, USA).

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Results

Lipid peroxidation results in the brain and liver

The mean lipid peroxidation levels of the brain in the three groups are shown in

Figure 2. The mean brain lipid peroxidation levels (as mol/g protein) at the 1st, 2nd and 3rd

weeks were 8.89, 8.93 and 9.17 in the controls, and 10.6, 10.9 and 11.9, 16.40 in the EMR

group, respectively. The lipid peroxidation levels in the brain samples were significantly

(p < 0.05) higher in the EMR groups than in the controls.

The mean lipid peroxidation levels of the liver in the three groups are shown in

Figure 3. The mean lipid peroxidation levels of the liver (as mol/g protein) at the 1st, 2nd

and 3rd weeks were significantly lower in the controls (15.60, 17.80 and 19.00,

respectively) than in the EMR groups (18.40, 20.90 [p < 0.05] and 23.30 [p < 0.01],

respectively). Hence, oxidative stress levels, as reflected by MDA levels, in the brain and

liver samples were increased in the development of newborn rats by the EMR exposures.

GSH and GSH-Px results in the brain and liver

The mean GSH level and GSH-Px activity of the brain and liver in the three groups

are shown in Tables 1 and 2, respectively. GSH-Px activities and GSH concentrations in the

brain and liver were significantly (p < 0.05) lower in the EMR groups than in the controls.

However, the liver GSH levels of the three groups did not change.

Antioxidant vitamin concentrations in the brain and liver

The mean vitamin A, -carotene, vitamin C and vitamin E concentrations of the brain

and liver in the three groups are shown in Tables 1 and 2. Vitamin A (p < 0.05 and

p < 0.001), -carotene (p < 0.01 for brain and p < 0.05 for liver) and vitamin C (p < 0.01 and

p < 0.001 for brain) concentrations in the brain and liver at three weeks were markedly

lower in the EMR group than in the controls. However, liver vitamin C concentrations were

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not affected by EMR exposure.

Discussion

Interest and scientific publications on environmental pollution and the exposure of

newborns to EMR has increased in the last decade. The exposure to EMR depends on the

length of time and frequency of use, which varies from individual to individual or because of

specific circumstances. Modern Wi-Fi internet devices work at a frequency of 2.45 GHz,

which was consequently selected for the present study. The brains and livers of newborns

within the first three weeks of life are very sensitive to oxidative injuries due to poor

antioxidant capacities. Several reports in adults have indicated that EMR exposure modifies

cellular oxidative stress and antioxidant redox systems in the foetus and newborn of animals

(Özorak et al. 2013; Çetin et al. 2014) and humans (Mendonca et al. 2011; Nguyen and

Goodman, 2012). The mechanism by which such effects could occur is not completely

understood, however, theories commonly include changes in ROS production. Hence, we

aimed to investigate 2.45 GHz EMR-induced oxidative stress and antioxidant changes in the

brains and livers of newborn rats.

We observed that brain and liver lipid peroxidation levels in the EMR-exposed groups

were increased compared with controls. Additionally, antioxidant vitamin and GSH

concentrations, and GSH-Px activities, were decreased in the brain and liver of EMR-exposed

groups. Results on the liver and brain of 2.45 GHz EMR-exposed adult rats and neurons

regarding the effects of oxidative stress in the pathogenesis of EMR have been reported

(Nazıroğlu and Gümral, 2009; Dasdag et al. 2009; Shahin et al. 2013; Nazıroğlu et al. 2012a;

Ghazizadeh and Nazıroğlu, 2014; Gürler et al. 2014). To the best of our knowledge, the

current study is the first to compare treatment with 2.45 GHz with particular reference to

oxidative stress in brain and liver of EMR-exposed newborn rats.

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Results of numerous studies indicate that the excessive production of ROS occurs

during EMR exposure. It is well known that 70–80% of cells contain water. Furthermore, a

foetus is contained within the amniotic fluid as well as having its own cellular water contents.

The water concentration of a newborn is also higher than in an adult. Newborn brains are

poorly protected from EMR injuries due to their thin skulls (Çetin et al. 2014). If the water

will be exposed to EMR decomposition occurs through which a variety of ROS and these

ROS formed in cells contribute EMR oxidative injury in brain and liver of newborns

(Nazıroğlu and Gumral, 2009; Selaković et al. 2013). In addition to ROS production, the

effects of EMR on oxygen, level and lifetime of free radicals are increased by EMR exposure

(Brocklehurst and McLauchlan, 1996). Furthermore, EMR can increase lipid peroxidation and

decrease antioxidant defence systems in the brain and liver (Nazıroğlu and Gümral, 2009;

Dasdag et al. 2009; Akdag et al. 2010; Shahin et al. 2013; Nazıroğlu et al. 2012a; Ghazizadeh

and Nazıroğlu, 2014; Rauš Balind et al. 2014). It also induces DNA damage in brain (Dasdag

et al. 2015a and 2015b). The EMR-induced ROS are scavenged by enzymatic substances such

as GSH-Px and catalase, and nonenzymatic antioxidants such as vitamins C and E (Halliwell,

2006; Nazıroğlu, 2007). Levels of enzymatic and nonenzymatic antioxidants in the brain are

considerably low; however, there are high rates of oxygen metabolism and PUFA contents in

the brain (Halliwell, 2006; Özmen et al. 2007). We recently observed that increased Ca2+

entry, through the activation of TRPM2 and TRPV1 channels, induces an overproduction of

ROS in neurons (Nazıroğlu et al. 2012a; Ghazizadeh and Nazıroğlu, 2014). Lipid

peroxidation levels in the brain and liver during rat development were increased in the EMR

groups; however, enzymatic and nonenzymatic antioxidant concentrations in the brain and

liver were also increased in the EMR groups. The decreased lipid peroxidation values could

be due to their depletion as a result of an increased production of oxidant radicals and

increased Ca2+ entry into the brain and liver.

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Vitamin E, as -tocopherol, is the most important fat-soluble antioxidant in the lipid

structure of cell membranes and organelles (Halliwell, 2006; Nazıroğlu, 2007). Vitamin E

has antioxidant and non-antioxidant molecular roles, and the scavenging of ROS is

performed by the antioxidant role of vitamin E (Jiang, 2014). Vitamin C (ascorbic acid) is a

water-soluble antioxidant, although its concentration is low in the brain compared to its

plasma and kidney levels (Frei et al. 1989). Oxidized vitamin E is converted to its active

form by vitamin C and GSH (Halliwell, 2006; Nazıroğlu, 2007). Hydrogen peroxide and

hydroxyl radicals are detoxified in the brain and liver by the selenium-dependent enzymatic

antioxidant, GSH-Px (Nazıroğlu, 2009). Antioxidant levels in the brain are considerably

low. Hence, a low antioxidant ascorbic acid concentration and a high content of PUFA

result in limited antioxidant defences in the brain. The GSH-Px activity; the vitamin A,

-carotene, and vitamin E concentrations in the brain and liver; and the vitamin C and GSH

concentrations in the liver of EMR-exposed newborn rats although lipid peroxidation

concentrations in the brain and liver were increased by the EMR exposure. The decreased

concentrations of the antioxidant vitamins could be due to their depletion or inhibition due

to the increased production of free radicals. The decrease of GSH-Px, GSH and antioxidant

vitamins in the brain and liver during the development of newborn rats has been attributed

to the induction of ROS and lipid peroxidation. Similarly, we recently observed decreased

vitamin A, -carotene, vitamin E and vitamin C concentrations in the kidneys, brains and

livers of adult rats and newborn rats produced by 2.45 GHz exposure (Nazıroğlu and

Gumral, 2009; Ozorak et al. 2013; Nazıroğlu et al. 2012a; Çetin et al. 2014).

In conclusion, these results demonstrated that Wi-Fi (2.45 GHz) devices might induce

oxidative toxicity through GSH, GSH-Px and antioxidant vitamin concentration decreases in

the brains and livers of rat pups during development. The results of lipid peroxidation and

antioxidant activity indicate that the brain was more sensitive to oxidative injury compared to

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the liver. However, further investigations in humans and babies are needed to clarify the

mechanism of action of the applied EMR exposure and oxidative stress on the rat brain and

liver as well as to establish the biological significance of the observed phenomena.

Duality of interest

The authors declare that there is no duality of interest associated with this manuscript.

Ethical statement

Pregnant Wistar albino rats weighing 190 ± 21 g at the ages of 10-12 weeks and and

their 48 newborns from Laboratory Animal Resources of Suleyman Demirel University

(SDU) (Isparta, Turkey) were utilized. All animal studies were conducted using approved

protocols and carried out in accordance with the Principles of Laboratory Animal Care (NIH

Publication no. 85-23, revised 1985). All procedures were approved by the Medical Faculty

Experimentation Ethics Committee of SDU (Protocol Number: 2013-03/02).

Authors’ contributions

Mustafa Nazıroğlu formulated the present hypothesis and was responsible for writing

the report. Ömer Çelik was responsible for analysis of the data.

Acknowledgement

The authors thank Assoc. Prof. Dr. Selçuk Çömlekçi (Electronics and Communication

Engineering Department, Suleyman Demirel University (SDU), Isparta, Turkey) for

calculation of SAR values and Z. Zahit Çiftçi (Department of Pedodontics, Faculty of

Dentistry, SDU, Isparta, Turkey) for helping experimental procedure.

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Table 1. Effects of Wi-Fi (2.45 GHz) frequencies on glutathione peroxidase (GSH-Px)

activity, reduced glutathione (GSH) and antioxidant vitamin concentrations in brain of

developing newborn rats (n = 8, mean ± SD).

AGE (WEEKS) Parameters Groups 1st 2nd 3rd

GSH-Px Control 12.49 ± 0.72 12.46 ± 1.33 13.39 ± 1.21 (IU/g protein)

EMR 10.27 ± 1.62a 9.63 ± 1.88a 8.89 ± 1.09b

GSH Control 6.97 ± 0.72 7.19 ± 0.38 6.97 ± 0.78 (μmol/g protein)

EMR 6.28 ± 0.38a 6.51 ± 0.52a 6.43 ± 0.48a

Vitamin A Control 1.98 ± 0.29 2.11 ± 0.31 2.33 ± 0.28 (μmol/g tissue)

EMR 2.16 ± 0.23a 2.56 ± 0.31b 2.76 ± 0.33a

β-carotene Control 0.88 ± 0.14 0.87 ± 0.16 0.89 ± 0.14 (μmol/g tissue)

EMR 1.10 ± 0.15b 1.15 ± 0.19b 1.24± 0.16b

Vitamin C Control 30.50 ± 9.57 29.80 ± 9.48 27.00 ± 6.61 (μmol/g tissue)

EMR 49.00 ± 8.55b 54.60 ± 4.22c 45.40 ± 8.58b

Vitamin E Control 13.01 ± 0.70 14.33 ± 1.02 15.58 ± 1.01 (μmol/g tissue) EMR 16.48 ± 0.90a 17.77 ± 1.41a 18.57 ± 1.45a ap<0.05, bp<0.01 and bp<0.001 as compared with group control at same week.

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Table 2. Effects of Wi-Fi (2.45 GHz) exposure on glutathione peroxidase (GSH-Px) activity,

reduced glutathione (GSH) and antioxidant vitamin concentrations in liver of developing

newborn rats (n = 8, mean ± SD).

AGE (WEEKS) Parameters Groups 1st 2nd 3rd

GSH-Px Control 18.49 ± 1.59 19.01 ± 1.60 19.25 ± 0.82 (IU/g protein)

EMR 16.46 ± 1.34a 17.06 ± 1.12a 17.39 ± 1.17a

GSH Control 9.99 ± 0.07 9.81 ± 0.34 9.35 ± 0.31 (μmol/g protein)

EMR 9.53 ± 0.14 9.45 ± 0.35 9.07 ± 0.61

Vitamin A Control 5.74 ± 0.37 6.31 ± 0.82 10.90 ± 0.78 (μmol/g tissue) EMR 4.14 ± 0.61a 3.63 ± 0.37b 4.63 ± 0.43b

β-carotene

Control

1.30 ± 0.10

1.42 ± 0.18

1.56 ± 0.19

(μmol/g tissue) EMR 1.17 ± 0.17a 1.26 ± 0.07a 1.41± 0.08a Vitamin C

Control

39.70 ± 8.03

48.30 ± 8.03

58.90 ± 13.60

(μmol/g tissue) EMR 38.30 ± 8.91 49.70 ± 8.98 51.10 ± 10.10 Vitamin E

Control

18.04 ± 0.97

18.18 ± 1.00

19.52 ± 2.08

(μmol/g tissue) EMR 15.82 ± 090a 14.57 ± 0.68c 14.83 ± 1.23a ap<0.05 and bp<0.001 as compared with group control at same week.

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Figure 1: The experimental set-up for irradiation of rats (Nazıroğlu and Gumral, 2009).

Figure 2. Effects of Wi-Fi (2.45 GHz) frequencies on lipid peroxidation levels in brain of

developing newborn rats (n = 8 and mean ± SD).

Figure 3. Effects of Wi-Fi (2.45 GHz) frequencies on lipid peroxidation levels in liver of

developing newborn rats (n = 8 and mean ± SD).

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Figure 1

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Figure 2

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Figure 3

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Highlights

Oxidative stress plays important role in biology of Wi-Fi (2.45 GHz)> 2.45 GHz increased

oxidative stress in brain and liver pregnant rats and their newborns.> Brain seems sensitive to

oxidative injury in the development of newborns.