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Abstract Radiation emitted from sources that are transmitted through an intermediated medium and absorbed by animal body. Radiation is very high up environmental toxin. Many sources of radiations are mobile phone, computer, UV lamp and torches radiation affected animal’s body organs such as thyroid gland, liver, kidney, etc. Radiations cause oxidative stress and generate free radicals such as hydroxyl radical, superoxide, nitric oxide, hydrogen peroxide radicals etc. These free radicals are unstable and chemically very active acting as an oxidizing agent that causes the morphological and physiological changes in the cells. In thyroid cells, these radicals can contact the other macromolecules and increase to changes in their structure and functions and hypo or hyperthyroidism conditions. An antioxidant our well wisher of damaging cells. Antioxidants inhibit the generation of free radicals and protect the cells. Antioxidants are essential for many enzymatic reactions and also acts as a free radical scavenger. Keywords: radiation, thyroid gland, oxidative stress, antioxidants
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International Journal of Biology Research
217
International Journal of Biology Research
ISSN: 2455-6548
Impact Factor: RJIF 5.22
www.biologyjournal.in
Volume 3; Issue 1; January 2018; Page No. 217-222
The effect of radiation on thyroid gland
Gayatri Rai, Arun Kumar, * Dr. Payal Mahobiya
Department of Zoology, Dr Harisingh Gour Vishwavidhyalaya, (A Central University), Sagar, Madhya Pradesh, India
Abstract
Radiation emitted from sources that are transmitted through an intermediated medium and absorbed by animal body. Radiation is
very high up environmental toxin. Many sources of radiations are mobile phone, computer, UV lamp and torches radiation affected
animal’s body organs such as thyroid gland, liver, kidney, etc. Radiations cause oxidative stress and generate free radicals such as
hydroxyl radical, superoxide, nitric oxide, hydrogen peroxide radicals etc. These free radicals are unstable and chemically very
active acting as an oxidizing agent that causes the morphological and physiological changes in the cells. In thyroid cells, these
radicals can contact the other macromolecules and increase to changes in their structure and functions and hypo or
hyperthyroidism conditions. An antioxidant our well wisher of damaging cells. Antioxidants inhibit the generation of free radicals
and protect the cells. Antioxidants are essential for many enzymatic reactions and also acts as a free radical scavenger.
Keywords: radiation, thyroid gland, oxidative stress, antioxidants
1. Introduction
People are affected by radiation from different sources.
Energy emitted from a source that is transmitted through an
intermediate medium and absorbed by the animal body.
Radiation is very high up environmental toxin and
transmission of energy in the form of particles or
waves through sources. Radiation impression of the ionizing
and non-ionizing radiation. Even though ionizing and non-
ionizing radiation has been used extensively in the many
sources such as a mercury lamp, dental polymerizing
equipment, X-rays machine, black light lamp, welding
equipment, counterfeit currency detectors, etc. Consequently,
radiation effect on the body organs such as the thyroid gland
[1, 2], eyes [3], liver [4], skin [5]. The UV radiation is
electromagnetic radiation and maximum generated from
sunlight. UV radiation is a non-ionizing and classified into
three types UV-C, UV-B & UV-A. UV-C (200-280 nm,
shortwave) is lethal than UV-B (280-320nm, medium wave).
It causes skin darkening and erythema, the skin cancer
possibility increases from long exposure to UV-B, UV-A is
non-lethal radiation (320-400 nm, long wave). UV radiation
damage cells and produced free radicals. Ionizing radiations
having high energy and short wavelength. It include X-rays,
gamma rays, alpha and beta particles. Ionizing radiation has
enough energy to generate ions. Which damage the cells,
enzymes, protein and nucleic acid [6, 7, 8].
Fig 1: Types of UV Radiation
The thyroid gland is the largest endocrine gland and consists
of two lobes beside the trachea and lowers the larynx. The
thyroid gland secretes the thyroid hormones which influence
the basal metabolic rate, protein synthesis and have a wide
range of other effects including on the development,
respectively. The thyroid hormones T3 and T4 are synthesized
from iodine and tyrosine in follicle cells. The thyroid also
produces calcitonin hormones; it plays a role in calcium
homeostasis.
Radiation generates the oxidative stress, Oxidative stress
founded when the imbalance between reactive oxygen species
(ROS) and antioxidants and cells tried to work against the
oxidant property and redox balance through the stimulation of
defensive enzymes, proteins [9, 10]. Even though oxidative
reactions arise in all tissues and organs, the thyroid gland
mobilizes such an organ in which oxidative processes are
essential for thyroid hormone synthesis. It is Putative that vast
quantity of ROS, particularly of hydrogen peroxide (H2O2),
are yield in the thyroid underneath physiological conditions.
Yet, with extra oxidative misuse caused by ionizing radiation,
improved damage to macromolecules occurs, potentially
leading to different thyroid diseases, also, cancer involved [11].
Non-ionizing radiation shows noxious effect of the thyroid
gland. This generates the free radicals. A radical is groups of
molecule that containing one or more unpaired electrons [12].
Free radicals generated by our body from a different type of
radiation. If free radicals extreme the body's capability to
control them, a situation known as oxidative stress. Free
radicals thus harmfully vary lipids, proteins, and DNA and
generate a number of human diseases [13]. There are many
types of radicals, but those of main concern in biological
systems are derived from oxygen, it called reactive oxygen
species. Superoxide anion, hydrogen peroxide, hydroxyl
radical is also reactive oxygen species. The Modern growth in
the information of free radicals and reactive oxygen species
International Journal of Biology Research
218
(ROS) in biology is Procreating a medical revolution that
promises a new age of health and disease administration [14].
Reactive oxygen species are also formed during the
metabolism of oxygen.
The noxious effect of ionizing radiation in natural systems are
mostly mediated through the generation of reactive oxygen
species (ROS) in cells as a result of water radiolysis [15],
render rise to OH- and H+ [8]. Ionizing radiation interacts with
biological systems to encourage the extreme flow of free
radicals that attack different cellular elements [16]. The effect
of ionizing radiation on the thyroid is well recognized [17]. The
pathophysiological description of radiation-induced thyroid
damage is related to inhibition of follicular epithelial function
and subsequent progressive alteration of the endothelium, the
effect increases by time [18, 19]. The possibility of thyroid
carcinoma after exposure to radiation doses higher than 0.05 -
0.1 Gy is higher in younger children at the time of exposure
and all efforts should be performed to avoid some radiation
exposure during childhood [20]. Several thyroid abnormalities
may be caused by radiation exposure [21].
Reactive oxygen species (ROS) together with partially
reduced forms of oxygen i.e. superoxide anion, hydrogen
peroxide and hydroxyl radical as well as organic counterparts
such as lipid peroxides are produced as natural consequences
of oxidative cell metabolism. Under physiological conditions,
ROS [22] generation is controlled by a large number of anti-
free radical systems which act as protective mechanisms.
These systems consist of antioxidant enzymes such as
superoxide dismutase, catalase, glutathione peroxidase, and
glutathione reductase as well as non-enzymatic antioxidants,
among which the most important vitamins C and E,
carotenoids, and glutathione. Interruption of the antioxidant
stability results since the increased generation of ROS,
inactivation of detoxification systems, or excessive
exploitation of antioxidants. The disturbance is a causative
factor in the oxidative damage of cellular structures and
molecules such as lipids, proteins, and nucleic acids [23].
The aim of present reviewed the effect of UV-radiation on the
thyroid gland and their oxidative effect of rats, the study of
preventive effects of antioxidant on rat thyroid activities.
2. Radiations
Radiations are an energy source, transmitted through a source
have sufficient energy to penetrate living and non-living cells.
Radiations are found in many forms and affected by the
natural environment and yield through recent technology.
Mostly radiations have the potential for both effects positive
and negative. Radiation-induced damage might result in
adverse health effects within hours to weeks and delayed
effects may be observable many months after exposure [4].
Even though sunlight very essential radiation of the entire can
be detrimental in extreme amounts. Basically, radiation
classified into two categories ionizing and non-ionizing.
Ionizing and non-ionizing radiation exerts its effects on the
thyroid gland, involving long-term damage cancer, both
radiations mostly targeted of several genes, protein, lipids and
cause cancer [24].
3. Thyroid and Ionizing Radiation
Ionizing radiation is not detected by any of our senses but can
be easily detected by electronic equipment. Ionizing radiation
is emitted by radioactive atoms. Its energy is high enough to
damage our bodies. Actuality, Ionizing radiation energy in the
form of waves or particles that has as much as a necessary
force to eliminate electrons from atoms. The quantity of
ionizing radiation that can be rendered to treat tumours are
limited due to the nearby normal tissues and organs in the
Proximity of a tumour that could be also exposed to the
radiation causing damage [25]. In humans and animals, ionizing
radiation may cause cancer, death, and failure of neural
function and also stimulate mutation, chromosomal
aberrations and apoptosis in cells [26, 27]. Ionizing radiation has
enough energy to generate ions. Ionizing radiations damage
the cells, enzymes, protein and nucleic acid [6, 7, 8].
HeNe laser has a potential therapeutic performance to
ameliorate the damaging effect of the ionizing radiation,
which depends on the frequency of its application. Further
studies with longer periods of treatment are recommended [28].
Even though oxidative reactions take place in all tissues and
organs, the thyroid gland constitutes such an organ in which
oxidative processes are indispensable for thyroid hormone
synthesis. It is estimated that huge amount of reactive oxygen
species, particularly of H2O2, are formed in the thyroid under
the physiological situation. Yet, with additional oxidative
mistreatment caused by IR, increased damage to
macromolecules occurs, potentially leading to different
thyroid diseases, cancer included [9].
4. Thyroid and Non-ionizing Radiation
Non-ionizing radiations are longer wavelength and low
energy. This radiation included UV radiation, visible light,
infrared; microwave, radiowave and these radiations are using
a Computer monitor, photocopier machine, printers, and
mercury lamps. Thyroid gland of rat exposed by exposure to
2.45 GHz radiation and obtained the glandular hypertrophy
in relation to the SAR and changes of the distribution of HSP-
90 linked with membranes and parafollicular cells and these
effects might not be absolutely formed by radiation and the
hypothalamus can be included with another indirect effect [29].
Table 1: Types of Non-Ionizing Radiation and their Wavelength
S. No
Non-Ionizing Radiation
Wavelength
1.
Ultraviolet
200-400nm
2.
Visible light
400-700nm
3.
Infrared
750nm-1m
4.
Microwave
1mm-1m
5.
Radiowave
1mm -100km
The thyroid gland is sensitive to EMF exposure and this
exposure induced morphological changes with drop off in
serum T4 and T3. These changes remained to the end of the
experiment indicating that a longer period of time is required
for the return of normal thyroid activity after EMF exposure.
Besides, the results revealed significant improvement in the
supervision of vitamin E through the exposure time [30].
5. Thyroid and UV Radiation
The UV radiations are major factors for set-up and
development of UV-initiated disease and Sunburn. [31, 32]
Prolonged exposure to solar-simulated UV irradiation leads to
International Journal of Biology Research
219
gathering of free radicals in the skin [33], immune suppression
and synthesis of excessive proinflammatory cytokines, all
resulting in oxidative stress in different tissues [34, 35]. UV
irradiation is known to induce apoptosis in many cell types [36,
37]. UV irradiation causes direct DNA damage (thymine
dimers) and forms bulky adducts that cause structural
distortion in the normal double-strand DNA backbone [38]. UV
irradiation could also diminish the intracellular content of
reduced glutathione [39] possibly through peroxidation of
lipids, causing the production of free hydroxyl radicals and a
state of oxidative stress in the cell; the resulting damage
occurs in proteins, lipids, and DNA. UV radiation exerts its
effects on the thyroid gland; involving long-term exposure
radiations mostly target several genes, protein, lipids and
causes cancer [21].
Fig 2: Exposure to UV radiation on rat and thyroid dysfunction by
the generation of free radicals.
Thyroid hormones are implicated in the control over the
oxidative stress in a very difficult way and the pre-exposition
to UV radiation tends to initiate oxidative stress in tissues, the
question arises about the effect of the prolonged exposition to
UV radiation on animals with hypothyroidism [40]. Ultraviolet
radiation was shown to induce a dose-dependent activation of
the apoptotic process in FTRL-5 cells cultured in the presence
of TSH [41, 42]. In the same cells flown in a stratospheric
balloon, a similar effect appeared to be the result of
modifications of the nuclear lipid metabolism, that is,
augmentation of sphingomyelin degradation and
phosphatidylcholine synthesis [43]. Acute and long-term
clinical manifestations of radiation exposure include the
development of cataracts; damage to the central nervous
system, gastrointestinal tract, skeletal system, and blood-
forming organs; and increased cancer risk. At high doses, it
also becomes an immediate threat to life. Different studies
have evaluated the plasma levels of key hormones involved in
the regulation of fluid volume, electrolyte concentrations, and
energetic metabolism in spaceflights conditions and have
found multiple changes in the response of the endocrine
system [44], Among these, functional alterations of the thyroid
suggestive of hypothyroidism have been documented in both
animals and humans [45, 46, 47, 48, 49, 43, 50, 51]. In particular,
decreased triiodothyronine (T3) and elevated thyroid-
stimulating hormone (TSH) plasma levels have been detected
in astronauts during spaceflights compared with prefight
values, and both hormones returned to the normal level in the
postflight period. Similarly, decreased thyroxine (T4) and T3
plasma concentrations have been shown in rats flown aboard a
biosatellite, together with morphological and histochemical
changes consistent with reduced thyroid activity, that is,
significant reduction of thyrocyte size, accumulation of colloid
drops in the cytoplasm, decrease of iodinated thyroglobulin in
the colloid, and lower T4 and T3 content per unit of thyroid
tissue mass [52].
The thyrotropin receptor is preferentially coupled to the alpha
subunit of the stimulatory guanine nucleotide binding protein
(Gsα) that activates adenylate cyclase and increases the
accumulation of cyclic AMP (cAMP). At higher thyrotropin
concentrations, the receptor also couples to the q subunit of
guaninenucleotidebinding protein alpha, resulting in the
activation of phospholipase C, and there is recent evidence
that the receptor may be coupled to members of other G
protein families [53]. In addition, insulin-like growth factor I,
epidermal growth factor, transforming growth factor β,
platelet-derived growth factor, fibroblast growth factor, and
cytokines, mainly acting by means of the protein tyrosine
kinase signal transduction pathway, stimulate the growth and
de differentiation of thyroid epithelial cells [54]. The growth
and function of the thyroid are stimulated by cAMP [54, 55].
This second messenger indirectly regulates the expression of
the thyroglobulin and thyroid peroxidase genes, whose
promoters contain binding sites for the transcription factors
TTF1, TTF2, and PAX8 [56]. As a consequence, continued
stimulation of the cAMP pathway causes hyperthyroidism
(Fig. 3).
Hypothyroidism may develop in patients with cutaneous T-
cell lymphoma who are treated with high-dose bexarotene,
most likely because the retinoid X receptor-selective ligand
suppresses thyrotropin secretion. Retinoid X receptor
selective ligands can suppress thyrotropin secretion, resulting
in central hypothyroidism [57].
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220
Fig 3: TSH receptor coupled to cAMP and regulated the hyperthyroidism and cell proliferation
6. Radiations and Antioxidants
An antioxidant our well-wisher of damaging cells.
Antioxidants inhibit the generation of free radicals and protect
the cells. Antioxidants are essential for many enzymatic
reactions and also acts as a free radical scavenger. the
administration of antioxidants namely Vitamin C, Vitamin E
and turmeric significantly increased in the circulating levels of
T3 and T4 and this hormones responded to antioxidants
representing the significance of antioxidants for the prevention
of occurrence of certain diseases in thyroid gland by
protecting biological system against potentially harmful
effects of processes or reactions that can cause excessive
oxidations [58].
7. Conclusion
This review looks at the generation of free radicals by the
radiation i.e. ionizing and non-ionizing radiations. Ionizing
radiation like x-rays, gamma rays and non-ionizing radiation
especially UV radiation generate the free radicals and
oxidative stress in the thyroid gland and determined changes
in thyroid hormones and their functions. Thyroid hormones
are implicated in the control over the oxidative stress in a very
difficult way and the pre-exposition to UV radiation tends to
initiate oxidative stress in tissues and the effect of the
prolonged exposition to UV radiation on animals with
hypothyroidism. Many receptors involved the thyroid
dysfunctions such as retinoid X receptor-selective ligands can
suppress thyrotropin secretion, resulting in central
hypothyroidism and TSH receptor (thyrotropin receptor) is
coupled mainly to the cAMP pathway by means of the alpha
subunit of the stimulatory guanine nucleotide binding protein.
The cAMP regulates the manufacture of thyroid hormone and
the proliferation of thyroid epithelial cells and thereby
mediates hyperthyroidism.
8. Acknowledgments
Authors thanks, Department of Zoology, Dr Harisingh Gour
Central University Sagar (M.P.), India for providing
infrastructural facilities and constant support and UGC-RGNF
for financial support.
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3(1):75-79.
... There is a growing evidence from researches indicating the association between IR and cancer. It is best represented by a linear nonthreshold model [1,2]. There is a general agreement that exposure to large doses of IR poses a serious risk to human health. ...
... These free radicals are chemically very active acting as oxidizing agents causing morphological and physiological changes in the cells. In thyroid gland cells, these radicals have the potential to interact with other macromolecules in thyroid cells and alter their structure and function, leading to hypo-or hyperthyroid disorders [2]. Therefore, the present study aimed to investigate whether exposed medical personnel are more likely to develop thyroid hormones and gland abnormalities. ...
... There is a growing evidence from researches indicating the association between IR and cancer. It is best represented by a linear nonthreshold model [1,2]. There is a general agreement that exposure to large doses of IR poses a serious risk to human health. ...
... These free radicals are chemically very active acting as oxidizing agents causing morphological and physiological changes in the cells. In thyroid gland cells, these radicals have the potential to interact with other macromolecules in thyroid cells and alter their structure and function, leading to hypo-or hyperthyroid disorders [2]. Therefore, the present study aimed to investigate whether exposed medical personnel are more likely to develop thyroid hormones and gland abnormalities. ...
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Background Ionizing radiation (IR) is high-energy radiation that has the potential to displace electrons from atoms and break chemical bonds. It has the ability to introduce mutations, DNA strand breakage, and cell death. Being a radiosensitive organ, exposure of the thyroid gland to IR can lead to significant changes in its function. Aim of the work Was to measure the levels of thyroid hormones panel and ultrasonography abnormalities in medical staff occupationally exposed to IR. Subjects and methods A total of 120 subjects were divided into three main groups: Group I: radiation-exposed workers occupationally exposed to radioiodine (131I) (n = 40), Group II: radiation-exposed workers occupationally exposed to X-ray (n = 40), and Group III: non-exposed healthy professionals matched in age and sex with the previous groups (n = 40). Thyroid hormones panel including free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone (TSH), anti-thyroperoxidase antibodies (anti-TPO), and thyroglobulin (Tg) were measured. Thyroid ultrasonography was performed. Oxidative stress markers such as malondialdehyde (MDA), hydrogen peroxide (H2O2), and total antioxidant capacity (TAC) were measured. Results Group I had significantly higher fT3 levels than the control group. fT3 levels were considerably higher, while TSH was substantially lower in group II participants than in the control group. Tg was markedly lower in radiation-exposed workers. However, anti-TPO levels in radiation-exposed workers were significantly higher than in the control group. MDA and H2O2 were substantially higher; TAC was significantly lower in radiation-exposed workers compared to the control group. According to ultrasonographic examination, thyroid volume and the percentage of thyroid nodules in all radiation workers were significantly higher than in the control group. Conclusion Despite low exposure doses, occupational exposure to IR affects the thyroid hormones and links with a higher likelihood of developing thyroid immune diseases.
... UVB radiation generates free radicals and causes oxidative stress affecting the endocrine system and its physiological processes, such as thyroid hormone action and the ovarian cycle (Rai et al., 2018, and. Thyroid hormones have played a biological role in animals; they regulate haematopoiesis in the bone marrow (Golde et al., 1977). ...
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Abstract The present study aimed to investigate the ameliorative effect of curcumin and ascorbic acid against ultraviolet (UVB)-induced thyroid toxicity and to study the haemtological and biochemical parameters. Twenty-four female Wistar rats, aged 3-4 months and weighing 130-150 g, were used, and the rats were divided into four Groups (Groups I to IV). Group I received standard food and water ad libitum and was treated as a control; Group II received a dose of 280 nm of UVB radiation for 2 hrs/day. Group III received 280 nm UVB radiation for 2 hrs/day and received curcumin 25 mg/kg body weight given orally. Group IV received 280 nm of UVB radiation for 2 hrs/day and received ascorbic acid 250 mg/kg body weight given orally. All the treatments were consequently performed for 15 days. The results showed that haemtological parameters such as haemoglobin (Hb) (p<0.05), red blood cells (RBCs), white blood cells (WBCs), MCV, MCH, and MCHC decreased significantly. Biochemical parameters included lipid peroxidation (LPO) (p<0.05), H2O2 (p<0.01), nitric oxide (NO), superoxide dismutase (SOD) (p< 0.01), catalase (p<0.01), glutathione-S-transferase (GST) (p<0.01), and glutathione reductase. NO increased, and glutathione (GSH) (p<0.01) decreased significantly. However, cotreatment with curcumin and ascorbic acid significantly increased the haemtological parameters. In addition, oxidative parameters such as LPO (p<0.01), SOD (p< 0.01), CAT (p<0.01), GST (p<0.01), and NO (p<0.01) significantly increased, and GSH (p<0.01) significantly decreased upon cotreatment with curcumin and ascorbic acid. The results indicated the ameliorative effect of curcumin and ascorbic acid against UVB-induced thyroid toxicity in female Wistar rats. Keywords: Ascorbic acid, Curcumin, Hematology, Oxidative stress, UVB radiation
... Ultraviolet B (UVB) radiation is the medium wavelength (280-320 nm) electromagnetic radiation and reaches the earth's surface due to ozone depletion and affects the biological system (Rai et al., 2018). Electromagnetic radiation has been used considerably in many resources such as mercury lamps, dental polymerizing devices, X-rays devices, blacklight lamps, welding systems, counterfeit money detectors, and so forth. ...
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Abstract: The present study therapeutic effects of curcumin and ascorbic acid against the alteration of the reproductive cycle via UVB-induced hyperthyroidism in female Wistar rats. Thirty-six female Wistar rats sexually matured older weight 130-150 g and aged 12-16 weeks had arbitrarily divided into six groups. The first group was a control group, which received standard food and water ad libitum. The second UVB group was exposed to a dose of 280 nm to UVB radiation for two hours daily. The third UVB+Curcumin group received 280 nm of UVB radiation for two hours daily and an oral dose of curcumin (25 mg/kg body weight) daily. The fourth UVB+Ascorbic acid group received 280 nm UVB radiation for two hours daily and an oral dose of ascorbic acid (250 mg/kg body weight) daily. The fifth, curcumin groups (25 mg/kg body weight), and the sixth is ascorbic acid groups (250 mg/kg body weight). All the treatments last for 15 consecutive days. UVB�induced hyperthyroidism caused structural alteration of the estrous cycle in the female Wistar rat compared to the control group. Curcumin and ascorbic acid prevent the estrous phases and their morphology. Index Terms: Ascorbic acid, Curcumin, Hyperthyroidism, Reproductive cycle, Wistar rat
... Even though sunlight very essential radiation of the entire can be detrimental in extreme amounts.Radiation impression of the ionizing and non-ionizing radiation.Even though ionizing and non-ionizing radiation has been used extensively in the many sources such as a mercury lamp, dental polymerizing equipment, X-rays machine, black light lamp, welding equipment, counterfeit currency detectors, etc. Consequently, radiation effect on the body organs such as the thyroid gland, eyes, liver, skin (Eşmekaya et al., 2010;Rai et al., 2018;Balci et al., 2009;Gultekin et al., 2013;Matsumura et al., 2004). Ionizing radiations having high energy and short wavelength. ...
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Introduction Radiation is very high up environmental toxin and transmission of energy in the form of particles or waves through sources. Radiations are an energy source, transmitted through a source have sufficient energy to penetrate living and non-living cells. Radiations are found in many forms and affected by the natural environment and yield through recent technology. Mostly radiations bear the potential for both effects positive and negative. Radiation-induced damage might result in adverse health effects within hours to weeks and delayed effects may be observable many months after exposure. Even though sunlight very essential radiation of the entire can be detrimental in extreme amounts.Radiation impression of the ionizing and non-ionizing radiation.Even though ionizing and non-ionizing radiation has been used extensively in the many sources such as a mercury lamp, dental polymerizing equipment, X-rays machine, black light lamp, welding equipment, counterfeit currency detectors, etc. Consequently, radiation effect on the body organs such as the thyroid gland, eyes, liver, skin (Eşmekaya et al., 2010; Rai et al., 2018; Balci et al., 2009; Gultekin et al., 2013; Matsumura et al., 2004). Ionizing radiations having high energy and short wavelength. It includes X-rays, gamma rays, alpha and beta particles. Ionizing radiation has enough energy to generate ions. Which damage the cells, enzymes, protein and nucleic acid (Lett et al., 1992; Dainiak et al., 1995; Kamat et al., 2000). Radiation generates the oxidative stress, Oxidative stress founded when the imbalance between reactive oxygen species (ROS) and antioxidants and cells tried to work against the oxidant property and redox balance through the stimulation of defensive enzymes, proteins (Dalton et al., 1999). Ionizing radiation interacts with biological systems to encourage the extreme flow of free radicals that attack different cellular elements (Shirazi et al., 2013).
... UV radiations are non-ionizing and are classified into three types UVC, UVB & UVA. UVC (200-280 nm, shortwave length) is lethal than UVB (280-320nm, medium wave length) [1,2,3].When cells or tissues are exposed to UV radiation, the water molecules undergo dissociation (radiolysis) and produce free radicals and related species in the form of ROS. These, in turn, can act on biomolecules such as DNA, lipids and proteins, and cause oxidative damage [4,5,6].The ovary is a primary functional organ of the female reproductive system, and it plays physiological roles body.Triiodothyronine (T3) and thyroxine (T4) are essential for normal reproductive function. ...
... The authors reported a correlation between thyroid irradiation, which occurs during a conversation on a mobile phone, and an increase in TSH levels. Electromagnetic radiation (EMR) is believed to cause oxidative stress and generate formation of a large number of free radicals, in particular, the hydroxyl radical of ozone, nitric oxide, hydrogen peroxide, etc. [22]. Because these substances are chemically unstable, they actively affect thyroid cells free radicals bind to other macromolecules and destabilize the morphological status of thyrocytes. ...
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The use of radiation technology in Indonesia is mostly applied in the medical world and is immensely beneficial, but radiation exposure also has negative effects on health in the form of deterministic and stochastic effects. The thyroid gland is at a high risk of radiation exposure, which leads to the development of thyroid nodules. To prevent that, there must be safety measures in the use of radiation technology by implementing radiation protection, such as a thyroid shield. This study aims to examine the effect of the compliant use of a thyroid shield on the development of thyroid nodules among radiographers in Malang. This study is an observational study with the use of secondary data, where the primary data were previously gathered cross-sectionally in April 2021. The data from 40 subjects were then analyzed using a T-test with the result of the t-value = 4.299 and α = 0.000. With the result of α < 0.05 and t-value > t-distribution, this study concludes that the use of a thyroid shield has an effect on the development of thyroid nodules among radiographers in Malang, and compliant use can lower the incidence of thyroid nodules. Keywords: Radiation exposure, radiographer, thyroid nodule, thyroid
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Introduction: Thyroid gland is one of the most important endocrine organs and almost all cells of the body are target sites for its hormones. Electromagnetic field became progressively more common constituent of the general and workplace environments. Aim of work: To evaluate the effect of low frequency electromagnetic fields (LF-EMF) on the structure and function of the thyroid gland and to evaluate their reversibility and role of vitamin E. Materials and Methods: Forty five adult male albino rats were equally divided into four groups; group I (control group), group II: rats were exposed to 50 Hz EMF for 1 month, group III: rats were received vitamin E just before EMF exposure for the same period and group IV (recovery group). At the time of sacrifice, blood samples were collected to estimate TSH, T3 and T4 levels. Thyroid gland specimens were processed for microscopic examination. The heights of follicular epithelium, collagen fiber area % were morphometrically estimated and statistically analyzed. Results: Exposed group showed significant decline T3 and T4 levels together with significant increase in TSH level as compared to other groups. Histologically, this group showed congestion and dilatation of blood capillaries, cellular infiltration, follicular disintegration and vacuolar degeneration of some follicular cells. Other apoptotic follicular cells appeared with condensed chromatin or desquamated. The epithelial height and connective tissue area also affected. Vitamin E improves the biochemical and histological picture of thyroid gland (group III). Recovery group (IV) had variable alteration as compared to other groups. Conclusion: LF-EMF has very serious effect on thyroid gland and vitamin E could have a protective role against this tissue damage.
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Radiation-induced damage is a complex network of interlinked signaling pathways, which may result in apoptosis, cell cycle arrest, DNA repair, and cancer. The development of thyroid cancer in response to radiation, from nuclear catastrophes to chemotherapy, has long been an object of study. A basic overview of the ionizing and non-ionizing radiation effects of the sensitivity of the thyroid gland on radiation and cancer development has been provided. In this review, we focus our attention on experiments in cell cultures exposed to ionizing radiation, ultraviolet light, and proton beams. Studies on the involvement of specific genes, proteins, and lipids are also reported. This review also describes how lipids are regulated in response to the radiation-induced damage and how they are involved in thyroid cancer etiology, invasion, and migration and how they can be used as both diagnostic markers and drug targets.
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This paper is an introduction to gravitational and space life sciences and a summary of key achievements in the field. Current global research is focused on understanding the effects of gravity/microgravity on microbes, cells, plants, animals and humans. It is now established that many plants and animals can progress through several generations in microgravity. Astrobiology is emerging as an exciting field promoting research in biospherics and fabrication of controlled environmental life support systems. India is one of the 14-nation International Space Exploration Coordination Group (2007) that hopes that someday humans may live and work on other planets within the Solar System. The vision statement of the Indian Space Research Organization (ISRO) includes planetary exploration and human spaceflight. While a leader in several fields of space science, India is yet to initiate serious research in gravitational and life sciences. Suggestions are made here for establishing a full-fledged Indian space life sciences programme. [Dayanandan P 2011 Gravitational biology and space life sciences: Current status and implications for the Indian space programme.
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The association between radiation exposure and the occurrence of thyroid cancer has been well documented, and the two main risk factors for the development of a thyroid cancer are the radiation dose delivered to the thyroid gland and the age at exposure. The risk increases after exposure to a mean dose of more than 0.05-0.1 Gy (50-100mGy). The risk is more important during childhood and decreases with increased age at exposure, being low in adults. After exposure, the minimum latency period before the appearance of thyroid cancers is 5 to 10 years. Papillary carcinoma (PTC) is the most frequent form of thyroid carcinoma diagnosed after radiation exposure, with a higher prevalence of the solid subtype in young children with a short latency period and of the classical subtype in cases with a longer latency period after exposure. Molecular alterations, including intra-chromosomal rearrangements, are frequently found. Among them, RET/PTC rearrangements are the most frequent. Current research is directed on the mechanism of genetic alterations induced by radiation and on a molecular signature that can identify the origin of thyroid carcinoma after a known or suspected exposure to radiation.
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Prolonged exposure to sunlight or solar simulated UV irradiation (SSUV) leads to oxidative stress in tissues. The literature data concerning the effect of this factor on hypothyroidism are controversial. The aim of this study was to investigate the influence of hypothyroidism and UV radiation on free radicals formation in rat's liver. After one week of adaptation, hypothyroid model was developed in 4 weeks, by continuous administration of 0.01% 6-n-propyl-2-thiouracil in the drinking water of male Wistar-Albino rats. Hypothyroidism was confirmed by the significant reduction of blood free thyroxin (approximately 0.44 ng/l, while 18 ng/l in the controls). The model was also proved by the loss of both appetite and body weight gain of the hypothyroid rats. During the 6-th week of the experiment, half of the PTU treated rats were irradiated with SSUV lamp for 60 min, divided into 4 portions with respective 15 min breaks. After decapitation, the accumulation of free radicals in rats' livers was measured spectrophotometrically using MTT-assay. Data were presented as percentage of the corresponding data for controls. Alone, SSUV irradiation increased, while hypothyroidism decreased the free radicals accumulation in the rat liver. This was in agreement with the literature data about the individual effects of these factors on the oxidative stress. When the SSUV irradiation was applied on the hypothyroid rats, the relative increase of the free radicals in the liver was much higher than that in the livers of SSUV irradiated normothyroid animals.
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Non-ionizing radiation at 2.45 GHz may modify the morphology and expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Diathermy is the therapeutic application of non-ionizing radiation to humans for its beneficial effects in rheumatological and musculo-skeletal pain processes. We used a diathermy model on laboratory rats subjected to maximum exposure in the left front leg, in order to study the effects of radiation on the nearby thyroid tissue. Fifty-six rats were individually exposed once or repeatedly (10 times in two weeks) for 30 min to 2.45 GHz radiation in a commercial chamber at different non-thermal specific absorption rates (SARs), which were calculated using the finite difference time domain technique. We used immunohistochemistry methods to study the expression of HSP-90 and morphological changes in thyroid gland tissues. Ninety minutes after radiation with the highest SAR, the central and peripheral follicles presented increased size and the thickness of the peripheral septa had decreased. Twenty-four hours after radiation, only peripheral follicles radiated at 12 W were found to be smaller. Peripheral follicles increased in size with repeated exposure at 3 W power. Morphological changes in the thyroid tissue may indicate a glandular response to acute or repeated stress from radiation in the hypothalamic-pituitary-thyroid axis. Further research is needed to determine if the effect of this physical agent over time may cause disease in the human thyroid gland. © 2015 by the Society for Experimental Biology and Medicine.
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Radiotherapy increases the risk of thyroid cancer (TC); patients submitted to this treatment should undergo a long-term follow-up. Our aim is to describe the features and outcomes of young patients who developed TC after radiotherapy. At our center, patients undergoing radiotherapy directly or indirectly involving the thyroid are regularly followed up in order to detect early dysfunction or nodules. Herein, we report the cases of 10 patients who were submitted to radiotherapy and developed TC. Seven patients were irradiated in the neck and 3 in nearby regions. The mean age at the last radiotherapy session was 10 ± 5.5 years. The average time until the appearance of the first thyroid nodule was 14 ± 4.7 years. The mean size increment of the nodules was 2.4 ± 1.6 mm/year. On the first cytology, only 2 results were suspicious of papillary thyroid cancer (PTC). All patients presented a histology of PTC. Eight were in stage I and 2 in stage II. The median follow-up from primary diagnosis to TC and beyond was 20 and 3 years, respectively. In these patients, cytologies may be difficult to interpret due to persistent benign results. The threshold for surgical indication may be anticipated, considering the increased risk of TC. We report the evolution of these nodules over time, from the end of primary oncological treatment.
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One inescapable feature of life on the earth is exposure to ionizing radiation. The thyroid gland is one of the most sensitive organs to gamma-radiation and endocrine disrupters. Low level laser therapy (LLLT) has been used to stimulate tissue repair, and reduce inflammation. The aim of this study was to gauge the value of using Helium-Neon laser to repair the damaged tissues of thyroid gland after gamma-irradiation. Albino rats were used in this study (144 rat), divided into control, gamma, laser, and gamma plus laser irradiated groups, each group was divided into 6 subgroups according to time of treatment (total 6 sessions). Rats were irradiated once with gamma radiation (6 Gy), and an external dose of laser [Wavelength 632.8 nm, 12 mW, CW, Illuminated area 5.73 cm(2) , 2.1 mW/cm(2) , 120 sec, 1.4 J, 0.252 J/cm(2) ] twice weekly localized on thyroid region of the neck, for a total of six sessions. Animals were sacrificed after each session. Analysis included thyroid function, oxidative stress markers, liver function and blood picture. Results revealed improvement in thyroid function, liver function and antioxidant levels, and the blood cells count after LLLT. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.