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Sozen E, Demirel-Yalciner T, Koroglu MK, Elmas MA, Ercan F, Ozer NK. High cholesterol diet activates ER stress mediated apoptosis in testes tissue: Role of α-tocopherol. IUBMB Life 2021; 74:85-92. [PMID: 34350697 DOI: 10.1002/iub.2535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/16/2021] [Accepted: 07/17/2021] [Indexed: 11/12/2022]
Abstract
The seminiferous tubules where spermatogenesis occurs are enveloped and protected by the Sertoli cells to support germ cells undergoing meiosis to produce haploid gametes. Clearly, induction of apoptosis in seminiferous tubules leads to abnormalities in spermatogenesis and male infertility. Studies demonstrated that increased hyperlipidemia impairs male infertility and spermatogenesis by enhancing seminiferous tubules apoptosis. However, molecular mechanisms underlying high-cholesterol-mediated testicular damage remain poorly elucidated. In this scope, we established a rabbit model and investigated the role of endoplasmic reticulum (ER) stress on high cholesterol diet induced seminiferous tubule apoptosis. Histopatological examinations revealed increased seminifer tubule apoptosis in testes of rabbits fed high cholesterol diet. In addition, phosphorylated forms of IRE1 and PERK, two well-identified markers of ER stress, were significantly induced in accordance with high cholesterol diet. High cholesterol diet also exhibited CHOP induction in testes, indicating increased ER stress related apoptosis. Supplementation of α-tocopherol significantly attenuated cholesterol mediated ER stress, and restored seminiferous tubules apoptosis. Taken together, our findings suggest that α-tocopherol might be capable to reduce testicular damage via ameliorating histopatological features and inhibiting seminiferous tubules apoptosis in hypercholesterolemic rabbits.
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Affiliation(s)
- Erdi Sozen
- Faculty of Medicine, Department of Biochemistry, Marmara University, Istanbul, Turkey.,Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, Istanbul, Turkey
| | | | - M Kutay Koroglu
- Faculty of Medicine, Department of Histology and Embryology, Marmara University, Istanbul, Turkey
| | - Merve Acikel Elmas
- Faculty of Medicine, Department of Histology and Embryology, Marmara University, Istanbul, Turkey.,Faculty of Medicine, Department of Histology and Embryology, Acıbadem Mehmet Ali Aydinlar University, Istanbul, Turkey
| | - Feriha Ercan
- Faculty of Medicine, Department of Histology and Embryology, Marmara University, Istanbul, Turkey
| | - Nesrin Kartal Ozer
- Faculty of Medicine, Department of Biochemistry, Marmara University, Istanbul, Turkey
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2
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Endoplasmic Reticulum Stress (ER Stress) and Unfolded Protein Response (UPR) Occur in a Rat Varicocele Testis Model. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:5909306. [PMID: 32802266 PMCID: PMC7411497 DOI: 10.1155/2020/5909306] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/14/2020] [Accepted: 05/29/2020] [Indexed: 12/12/2022]
Abstract
Using a surgically induced varicocele rat model, we show here strong evidence that the misfolded/unfolded protein response that is part of the stress response of the endoplasmic reticulum (ER) is activated in the varicocele testis (VCL), leading to the induction of apoptosis. To support this hypothesis, it is observed that the spliced variant of the X-box protein 1 (XBP1s), resulting from the activation of the inositol-requiring enzyme 1 (IRE1) membrane sensor, is significantly more represented in VCL testicular extracts. The activation of the IRE1/XBP1s pathway is also supported by the observation that the VCL testes show an increase phosphorylation of the c-Jun-kinase (JNK) known to be one intermediate of this pathway and an increased level of caspase-3, the terminal apoptotic effector, partly explaining the apoptotic status of the VCL testis.
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3
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Wang M, Wang J, Liu Y, Wang J, Nie Y, Si B, Liu Y, Wang X, Chen S, Hei TK, Wu L, Zhao G, Xu A. Subcellular targets of zinc oxide nanoparticles during the aging process: role of cross-talk between mitochondrial dysfunction and endoplasmic reticulum stress in the genotoxic response. Toxicol Sci 2019; 171:159-171. [PMID: 31173148 DOI: 10.1093/toxsci/kfz132] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 04/17/2019] [Accepted: 05/16/2019] [Indexed: 12/18/2022] Open
Abstract
Zinc oxide nanoparticles (ZnO NPs) are being produced abundantly and applied increasingly in various fields. The special physicochemical characteristics of ZnO NPs makes them incline to undergo physicochemical transformation over time (aging), which modify their bioavailability and toxicity. However, the subcellular targets and the underlying molecular mechanisms involved in the genotoxicity induced by ZnO NPs during aging process are still unknown. The present study found that the acute cytotoxic effects of fresh ZnO NPs was largely regulated by mitochondria-dependent apoptosis, which the level of cleaved Caspase-3 and mitochondria damage were significantly higher than that of 60 day-aged ZnO NPs. In contrast, aged ZnO NPs induced more reactive oxygen species (ROS) production and endoplasmic reticulum (ER) stress marker protein (BIP/GRP78) expression and their genotoxicity could be dramatically suppressed by either ROS scavengers (DMSO, CAT and NaN3) or ER stress inhibitor (4-PBA). Using mitochondrial-DNA deficient (ρ0) AL cells, we further found that ER stress induced by aged ZnO NPs was triggered by ROS generated from mitochondria, which eventually mediated the gentoxicity of aged NPs. Our data provided novel information on better understanding the contribution of subcellular targets to the genotoxic response of ZnO NPs during the aging process.
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Affiliation(s)
- Meimei Wang
- Department of Pathophysiology, Anhui Medical University, No.81, Mei-Shan Road, Hefei, Anhui, P. R. China
| | - Juan Wang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,University of Science and Technology of China, Hefei, Anhui, P. R. China
| | - Yun Liu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China
| | - Jingjing Wang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,University of Science and Technology of China, Hefei, Anhui, P. R. China
| | - Yaguang Nie
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, P. R. China
| | - Bo Si
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,University of Science and Technology of China, Hefei, Anhui, P. R. China
| | - Ying Liu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,University of Science and Technology of China, Hefei, Anhui, P. R. China
| | - Xue Wang
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,University of Science and Technology of China, Hefei, Anhui, P. R. China
| | - Shaopeng Chen
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China
| | - Tom K Hei
- Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, New York, New York, United States
| | - Lijun Wu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, P. R. China
| | - Guoping Zhao
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China
| | - An Xu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Chinese Academy of Sciences; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.,Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui, P. R. China
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4
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Kooptiwut S, Kaewin S, Semprasert N, Sujjitjoon J, Junking M, Suksri K, Yenchitsomanus PT. Estradiol Prevents High Glucose-Induced β-cell Apoptosis by Decreased BTG2 Expression. Sci Rep 2018; 8:12256. [PMID: 30115961 PMCID: PMC6095866 DOI: 10.1038/s41598-018-30698-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 08/03/2018] [Indexed: 01/20/2023] Open
Abstract
Hyperglycemia stimulates several pathways to induce pancreatic β-cell apoptosis. In our previous study by mRNA analysis, we demonstrated that B-cell translocation gene 2 (BTG2) expression was up-regulated in INS-1 cells cultured under high glucose conditions, but this effect was reversed by estrogen. In the present study, we demonstrated that BTG2 mRNA and protein expressions in both INS-1 cells and mouse pancreatic islets increased under high glucose conditions compared to those cultured under basal glucose conditions, while in the presence of estrogen, the BTG2 mRNA and protein expressions decreased. SiRNA-BTG2 significantly reduced cell apoptosis, cleaved-caspase 3, and Bax, compared to the siRNA-control in INS-1 cultured under high glucose conditions. We further demonstrated that BTG2 promoter activity was activated under high glucose conditions whereas estrogen significantly reduced it. The effects of estrogen on BTG2 expression were inhibited by estrogen receptor inhibitors. Also, under high glucose conditions, p53 and Bax mRNA and protein expressions increased, but they decreased in the presence of estrogen. Again, the effect of estrogen on p53 and Bax expression was inhibited by estrogen receptor inhibitors. Taken together, this study demonstrates that estrogen reduces pancreatic β-cell apoptosis under high glucose conditions via suppression of BTG2, p53, and Bax expressions.
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Affiliation(s)
- Suwattanee Kooptiwut
- Department of Physiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Suchada Kaewin
- Department of Physiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Namoiy Semprasert
- Department of Physiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Jatuporn Sujjitjoon
- Division of Molecular Medicine, Research Department, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Mutita Junking
- Division of Molecular Medicine, Research Department, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Kanchana Suksri
- Department of Physiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Pa-Thai Yenchitsomanus
- Division of Molecular Medicine, Research Department, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
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5
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Li M, Gu MM, Tian X, Xiao BB, Lu S, Zhu W, Yu L, Shang ZF. Hydroxylated-Graphene Quantum Dots Induce DNA Damage and Disrupt Microtubule Structure in Human Esophageal Epithelial Cells. Toxicol Sci 2018; 164:339-352. [PMID: 29669094 PMCID: PMC6016703 DOI: 10.1093/toxsci/kfy090] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Graphene quantum dots (GQDs) have attracted significant interests due to their unique chemical and physical properties. In this study, we investigated the potential effects of hydroxyl-modified GQDs (OH-GQDs) on the human esophageal epithelial cell line HET-1A. Our data revealed significant cytotoxicity of OH-GQDs which decreased the viability of HET-1A in a dose and time-dependent manner. The moderate concentration (25 or 50 µg/ml) of OH-GQDs significantly blocked HET-1A cells in G0/G1 cell cycle phase. An increased percentage of γH2AX-positive and genomically unstable cells were also detected in cells treated with different doses of OH-GQDs (25, 50, and 100 µg/ml). Microarray data revealed that OH-GQDs treatment down-regulated genes related to DNA damage repair, cell cycle regulation and cytoskeleton signal pathways indicating a novel role of OH-GQDs. Consistent with the microarray data, OH-GQDs disrupted microtubule structure and inhibited microtubule regrowth around centrosomes in HET-1A cells. In conclusion, our findings provide important evidence for considering the application of OH-GQDs in biomedical fields.
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Affiliation(s)
- Ming Li
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
| | - Meng-Meng Gu
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
| | - Xin Tian
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
| | - Bei-Bei Xiao
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
| | - Siyuan Lu
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
| | - Wei Zhu
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
| | - Lan Yu
- Suzhou Digestive Diseases and Nutrition Research Center, Nanjing Medical University Affiliated Suzhou Hospital, North District of Suzhou Municipal Hospital, Suzhou 215000, People’s Republic of China
| | - Zeng-Fu Shang
- State Key Laboratory of Radiation Medicine and Protection, Department of Radiobiology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, People’s Republic of China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People’s Republic of China
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6
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Maghsudlu M, Farashahi Yazd E. Heat-induced inflammation and its role in esophageal cancer. J Dig Dis 2017; 18:431-444. [PMID: 28749599 DOI: 10.1111/1751-2980.12511] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 06/22/2017] [Accepted: 07/24/2017] [Indexed: 12/11/2022]
Abstract
Esophageal cancer, the sixth most common cause of death from cancer worldwide, consists of different histological types and displays various patterns of incidence. Esophageal adenocarcinoma and esophageal squamous cell carcinoma are the most prevalent types. As epidemiological studies report that ingesting hot substances is one major risk factor for squamous cell carcinoma, evaluating the effect of this external stress on esophagus cells seems desirable. This specific kind of stress brings about cellular changes and stabilizes them by affecting different cellular features such as genetic stability, membrane integrity and the regulation of signaling pathways. It also causes tissue injury by affecting the extracellular matrix and cell viability. Thus, one of the main consequences of thermal injury is the activation of the immune system, which can result in chronic inflammation. The genetic alteration that has occurred during thermal injury and the consequent reduction in the function of repair systems is further strengthened by chronic inflammation, thereby increasing the probability that mutated cell lines may appear. The molecules that present in this circumstance, such as heat shock proteins, cytokines, chemokines and other inflammatory factors, affect intercellular signaling pathways, including nuclear factor kappa-light-chain-enhancer of activated B cells, signal transducer activator of transcription-3 and hypoxia-inducible factor 1α in supporting the survival and emergence of mutant phenotypes and the consequent malignant progression in altered cell lines. This investigation of these effective factors and their probable role in the tumorigenic path may improve current understanding.
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Affiliation(s)
- Mohaddese Maghsudlu
- Stem Cell Biology Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.,Department of Genetics, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Ehsan Farashahi Yazd
- Stem Cell Biology Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
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7
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Gu XW, Yan JQ, Dou HT, Liu J, Liu L, Zhao ML, Liang XH, Yang ZM. Endoplasmic reticulum stress in mouse decidua during early pregnancy. Mol Cell Endocrinol 2016; 434:48-56. [PMID: 27283502 DOI: 10.1016/j.mce.2016.06.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 05/10/2016] [Accepted: 06/05/2016] [Indexed: 02/07/2023]
Abstract
Unfolded or misfolded protein accumulation in the endoplasmic reticulum lumen leads to endoplasmic reticulum stress (ER stress). Although it is known that ER stress is crucial for mammalian reproduction, little is known about its physiological significance and underlying mechanism during decidualization. Here we show that Ire-Xbp1 signal transduction pathway of unfolded protein response (UPR) is activated in decidual cells. The process of decidualization is compromised by ER stress inhibitor tauroursodeoxycholic acid sodium (TUDCA) and Ire specific inhibitor STF-083010 both in vivo and in vitro. A high concentration of ER stress inducer tunicamycin (TM) suppresses stromal cells proliferation and decidualization, while a lower concentration is beneficial. We further show that ER stress induces DNA damage and polyploidization in stromal cells. In conclusion, our data suggest that the GRP78/Ire1/Xbp1 signaling pathway of ER stress-UPR is activated and involved in mouse decidualization.
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Affiliation(s)
- Xiao-Wei Gu
- Department of Biology, Shantou University, Shantou 515063, China; College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Jia-Qi Yan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Hai-Ting Dou
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Jie Liu
- Department of Biology, Shantou University, Shantou 515063, China
| | - Li Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Meng-Long Zhao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xiao-Huan Liang
- College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Zeng-Ming Yang
- Department of Biology, Shantou University, Shantou 515063, China; College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.
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8
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Le Quément C, Nicolaz CN, Habauzit D, Zhadobov M, Sauleau R, Le Dréan Y. Impact of 60-GHz millimeter waves and corresponding heat effect on endoplasmic reticulum stress sensor gene expression. Bioelectromagnetics 2014; 35:444-51. [PMID: 25099539 DOI: 10.1002/bem.21864] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 05/17/2014] [Indexed: 12/12/2022]
Abstract
Emerging high data rate wireless communication systems, currently under development, will operate at millimeter waves (MMW) and specifically in the 60 GHz band for broadband short-range communications. The aim of this study was to investigate potential effects of MMW radiation on the cellular endoplasmic reticulum (ER) stress. Human skin cell lines were exposed at 60.4 GHz, with incident power densities (IPD) ranging between 1 and 20 mW/cm(2) . The upper IPD limits correspond to the ICNIRP local exposure limit for the general public. The expression of ER-stress sensors, namely BIP and ORP150, was then examined by real-time RT-PCR. Our experimental data demonstrated that MMW radiations do not change BIP or ORP150 mRNA basal levels, whatever the cell line, the exposure duration or the IPD level. Co-exposure to the well-known ER-stress inducer thapsigargin (TG) and MMW were then assessed. Our results show that MMW exposure at 20 mW/cm(2) inhibits TG-induced BIP and ORP150 over expression. Experimental controls showed that this inhibition is linked to the thermal effect resulting from the MMW exposure.
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Affiliation(s)
- Catherine Le Quément
- Transcription, Environment and Cancer Group, Institute of Research in Environmental and Occupational Health-IRSET, INSERM, University of Rennes 1, Rennes, France
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