Medical/biological study (experimental study)

The effect of melatonin on the liver of rats exposed to microwave radiation med./bio.

By: Djordjevic B, Sokolovic D, Kocic G, Veljkovic A, Despotovic M, Basic J, Jevtovic-Stoimenov T, Sokolovic DM

Published in: Bratisl Lek Listy 2015; 116 (2): 96-100

Aim of study (acc. to author)

The effects of exposure of rats to a 900 MHz electromagnetic field and co-exposure to melatonin on oxidative stress in the liver should be investigated.

Background/further details

84 rats were divided into 4 groups (n=21 each): 1) control group, 2) administration of melatonin, 3) exposure to microwaves, 4) administration of melatonin and exposure to microwaves. Seven animals of each group were sacrificed and examined after 20, 40 and 60 days of exposure, respectively.
2 mg/kg body weight melatonin was administered intraperitoneally every morning in groups 2 and 4. Animals of the control group received an equal volume of isotonic saline solution.

Endpoint

oxidative stress in the rat liver

Exposure

- 900 MHz
- RF field
- mobile communications
- GSM
- co-exposure

Exposure	Parameters
Exposure 1: 900 MHz Modulation type: CW Exposure duration: continuous for 4h/day for 20, 40 or 60 days	magnetic flux density: 4.86 µT minimum (according to abstract 100 µT (?)) magnetic flux density: 8.69 µT maximum (according to abstract 300 µT (?)) electric field strength: 9.88 V/m minimum (according to abstract 54 V/m (?)) electric field strength: 18.356 V/m maximum (according to abstract 160 V/m (?)) SAR: 0.089 W/g mean (whole body)

Exposure 1

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Charakteristic	near field
Exposure duration	continuous for 4h/day for 20, 40 or 60 days
Additional info	GSM frequency band-mobile transmitting signal

Modulation

Modulation type	CW

Exposure setup

Exposure source	cellular phone
Chamber	plastic cage without metallic fittings
Setup	rats placed in plastic cage containing a mobile phone (Nokia 3110) with antenna positioned downwards; animals were able to move freely during exposure

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	4.86 µT	minimum	measured	-	according to abstract 100 µT (?)
magnetic flux density	8.69 µT	maximum	measured	-	according to abstract 300 µT (?)
electric field strength	9.88 V/m	minimum	measured	-	according to abstract 54 V/m (?)
electric field strength	18.356 V/m	maximum	measured	-	according to abstract 160 V/m (?)
SAR	0.089 W/g	mean	estimated	whole body	-

Exposed system:

animal
rat/Wistar albino
whole body

Methods Endpoint/measurement parameters/methodology

oxidative stress: lipid peroxidation (reaction of malondialdehyde with thiobarbituric acid), protein oxidation (carbonyl group content), enzyme activity of catalase, xanthine oxidase, alkaline deoxyribonuclease I and acid deoxyribonuclease II (markers for apoptosis); total protein content (Lowry's method) (spectrophotometry)

Investigated system:

isolated bio./chem. substance
liver homogenates

Time of investigation:

during exposure
after exposure

Main outcome of study (acc. to author)

The lipid peroxidation was significantly increased in group 3 (exposure to microwaves) compared to the control group after 40 and 60 days of exposure. At the same time, it was significantly reduced in group 4 (melatonin + microwaves) compared to group 3.
Moreover, protein oxidation was significantly increased after 20, 40 and 60 days, catalase and xanthine oxidase enzyme activity were significantly increased after 40 and 60 days and the enzyme activity of alkaline deoxyribonuclease I was significantly increased after 60 days of exposure in group 3 compared to the control group and group 2 (melatonin only).
The authors conclude that exposure of rats to a 900 MHz electromagnetic field could cause oxidative stress in the liver and that melatonin might have an antioxidant effect by reducing lipid peroxidation.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Ministry of Education and Science, Serbia

Bodera P et al. (2015): Influence of electromagnetic field (1800 MHz) on lipid peroxidation in brain, blood, liver and kidney in rats
Holovska K et al. (2015): Structural and Ultrastructural Study of Rat Liver Influenced by Electromagnetic Radiation
Ragy MM (2015): Effect of exposure and withdrawal of 900-MHz-electromagnetic waves on brain, kidney and liver oxidative stress and some biochemical parameters in male rats
Furtado-Filho OV et al. (2014): Effect of 950 MHz UHF Electromagnetic radiation on biomarkers of oxidative damage, metabolism of UFA and antioxidants in the liver of young rats of different ages
Meena R et al. (2014): Therapeutic approaches of melatonin in microwave radiations-induced oxidative stress-mediated toxicity on male fertility pattern of Wistar rats
Sokolovic D et al. (2013): Melatonin protects rat thymus against oxidative stress caused by exposure to microwaves and modulates proliferation/apoptosis of thymocytes
Aynali G et al. (2013): Modulation of wireless (2.45 GHz)-induced oxidative toxicity in laryngotracheal mucosa of rat by melatonin
Bilgici B et al. (2013): Effect of 900 MHz radiofrequency radiation on oxidative stress in rat brain and serum
Avci B et al. (2012): Oxidative stress induced by 1.8 GHz radio frequency electromagnetic radiation and effects of garlic extract in rats
Kumari K et al. (2012): Radiofrequency electromagnetic field exposure effects on antioxidant enzymes and liver function tests
Naziroglu M et al. (2012): Melatonin modulates wireless (2.45 GHz)-induced oxidative injury through TRPM2 and voltage gated Ca(2+) channels in brain and dorsal root ganglion in rat
Guler G et al. (2012): The effect of radiofrequency radiation on DNA and lipid damage in female and male infant rabbits
Esmekaya MA et al. (2011): 900 MHz pulse-modulated radiofrequency radiation induces oxidative stress on heart, lung, testis and liver tissues
Ozgur E et al. (2010): Mobile phone radiation-induced free radical damage in the liver is inhibited by the antioxidants N-acetyl cysteine and epigallocatechin-gallate
Tomruk A et al. (2010): The influence of 1800 MHz GSM-like signals on hepatic oxidative DNA and lipid damage in nonpregnant, pregnant, and newly born rabbits
Koyu A et al. (2009): The protective effect of caffeic acid phenethyl ester (CAPE) on oxidative stress in rat liver exposed to the 900 MHz electromagnetic field
Guney M et al. (2007): 900 MHz radiofrequency-induced histopathologic changes and oxidative stress in rat endometrium: protection by vitamins E and C
Oktem F et al. (2005): Oxidative damage in the kidney induced by 900-MHz-emitted mobile phone: protection by melatonin
Koyu A et al. (2005): Caffeic Acid Phenethyl Ester Modulates 1800 MHz Microwave-Induced Oxidative Stress in Rat Liver
Özgüner F et al. (2005): Comparative analysis of the protective effects of melatonin and caffeic acid phenethyl ester (CAPE) on mobile phone-induced renal impairment in rat
Özgüner F et al. (2005): A novel antioxidant agent caffeic acid phenethyl ester prevents long-term mobile phone exposure-induced renal impairment in rat. Prognostic value of malondialdehyde, N-acetyl-beta-D-glucosaminidase and nitric oxide determination
Özgüner F et al. (2004): Prevention of mobile phone induced skin tissue changes by melatonin in rat: an experimental study