ABSTRACT
Radiofrequency radiation (RFR) was classified as a "possible" human carcinogen in 2011, which caused great public concern. A carcinogenicity study by the National Toxicology Program (NTP) found Code Division Multiple Access-and Global System for Mobile Communications-modulated mobile phone RFR to be carcinogenic to the brain and heart of male rats. As part of an investigation of mobile phone carcinogenesis, and to verify the NTP study results, a 5-year collaborative animal project was started in Korea and Japan in 2019. An international animal study of this type has two prerequisites: use of the same study protocol and the same RF-exposure system. This article discusses our experience in the design of this global study on radiofrequency electromagnetic fields (RF-EMFs).© 2022 The Authors. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society.
Subject(s)
Cell Phone , Radio Waves , Animals , Brain , Carcinogenesis , Electromagnetic Fields , Male , RatsABSTRACT
The placenta protects the fetus against excessive stress-associated maternal cortisol during pregnancy. We studied whether exposure to radiofrequency electromagnetic field (RF-EMF) radiation during pregnancy can cause changes in dams and their placentas. Pregnant Sprague-Dawley rats were divided into cage-control, sham-exposed, and RF-exposed groups. They were exposed to RF-EMF signals at a whole-body specific absorption rate of 4 W/kg for 8 h/day from gestational Day 1 to 19. Levels of cortisol in the blood, adrenal gland, and placenta were measured by enzyme-linked immunosorbent assay. Levels of adrenocorticotropic hormone and corticotropin-releasing hormone were monitored in maternal blood. Expression levels of placental 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2) messenger RNA (mRNA) were measured by reverse transcription polymerase chain reaction. Morphological changes in the placenta were analyzed using hematoxylin and eosin staining. Fetal parts of the placenta were measured using Zen 2.3 blue edition software. Maternal cortisol in circulating blood (RF: 230 ± 24.6 ng/ml and Sham: 156 ± 8.3 ng/ml) and the adrenal gland (RF: 58.3 ± 4.5 ng/ml and Sham: 30 ± 3.8 ng/ml) was significantly increased in the RF-exposed group (P < 0.05). Placental cortisol was stably maintained, and the level of placental 11ß-HSD2 mRNA expression was not changed in the RF-exposed group. RF-EMF exposure during pregnancy caused a significant elevation of cortisol levels in circulating blood; however, no changes in the placental barrier were observed in pregnant rats. Bioelectromagnetics. © 2021 Bioelectromagnetics Society.
Subject(s)
Electromagnetic Fields , Placenta , 11-beta-Hydroxysteroid Dehydrogenase Type 2 , Animals , Electromagnetic Fields/adverse effects , Female , Hydrocortisone , Pregnancy , Rats , Rats, Sprague-DawleyABSTRACT
Exposure to a radiofrequency (RF) signal at a specific absorption rate (SAR) of 4 W/kg can increase the body temperature by more than 1 °C. In this study, we investigated the effect of anesthesia on the body temperature of rats after exposure to an RF electromagnetic field at 4 W/kg SAR. We also evaluated the influence of body mass on rats' body temperature. Rats weighing 225 and 339 g were divided into sham- and RF-exposure groups. Each of the resulting four groups was subdivided into anesthetized and non-anesthetized groups. The free-moving rats in the four RF-exposure groups were subjected to a 915 MHz RF identification signal at 4 W/kg whole-body SAR for 8 h. The rectal temperature was measured at 1-h intervals during RF exposure using a small-animal temperature probe. The body temperatures of non-anesthetized, mobile 225 and 339 g rats were not significantly affected by exposure to an RF signal. However, the body temperatures of anesthetized 225 and 339 g rats increased by 1.9 °C and 3.3 °C from baseline at 5 and 6 h of RF exposure, respectively. Three of the five 339 g anesthetized and exposed rats died after 6 h of RF exposure. Thus, anesthesia and body mass influenced RF exposure-induced changes in the body temperature of rats. Bioelectromagnetics. 2020;41:104-112. © 2019 Bioelectromagnetics Society.
Subject(s)
Anesthesia , Body Temperature/physiology , Electromagnetic Fields/adverse effects , Animals , Electromagnetic Radiation , Male , Radio Waves/adverse effects , Rats, Sprague-DawleyABSTRACT
Olfactory loss is known to affect both mood and quality of life. Transient anosmia was induced in mice to study the resulting changes in mood, behavior, and on a molecular level. Transient anosmia was induced by a single intranasal instillation of ZnSO4 in BALB/c mice. Hematoxylin and eosin (HE) staining, and potato chip finding test were performed to confirm olfactory loss. Tail suspension, forced swim, and splash tests were performed to evaluate depression-related behavior; while the open field, and elevated plus maze tests were used to evaluate anxiety-related behavior. The mRNA levels of amygdalar corticotropin-releasing hormone (CRH) and hypothalamic glucocorticoid receptor (GR) were quantified using real-time PCR to confirm relevant molecular change. Olfactory loss was confirmed 1-2.5 weeks after induction, and this loss was subsequently reversed over time. The results of the behavioral tests indicated increased depression-like and reduced anxiety-like behavior at week 1. Accordingly, PCR data identified decreased amygdalar CRH expression at week 1. These results suggest that transient anosmia induces both depressive and anxiolytic behavior as a result of decreased amygdalar CRH in a mouse model of anosmia.
Subject(s)
Behavior, Animal/drug effects , Corticotropin-Releasing Hormone/metabolism , Olfaction Disorders/pathology , Zinc Sulfate/toxicity , Administration, Intranasal , Amygdala/metabolism , Animals , Anxiety/etiology , Corticotropin-Releasing Hormone/genetics , Depression/etiology , Disease Models, Animal , Hypothalamus/metabolism , Male , Maze Learning , Mice , Mice, Inbred BALB C , Olfaction Disorders/chemically induced , Olfaction Disorders/complications , Olfactory Mucosa/pathology , Receptors, Glucocorticoid/genetics , Receptors, Glucocorticoid/metabolismABSTRACT
We investigated whether exposure to the 915 MHz radiofrequency identification (RFID) signal affected circulating blood cells in rats. Sprague-Dawley rats were exposed to RFID at a whole-body specific absorption rate of 2 W/kg for 8 h per day, 5 days per week, for 2 weeks. Complete blood counts were performed after RFID exposure, and the CD4+ /CD8+ ratio was determined by flow cytometry. The number of red blood cells (RBCs) and the values of hemoglobin, hematocrit, and RBC indices were increased in the RFID-exposed group compared with those in the cage-control and sham-exposed groups (P < 0.05). However, the RBCs and platelet numbers were within normal physiologic response ranges. The number of white blood cells, including lymphocytes, was decreased in RFID-exposed rats. However, there was no statistically significant difference between the sham-exposed and RFID-exposed groups in terms of T-cell counts or CD4+ /CD8+ ratio (P > 0.05). Although the number of circulating blood cells was significantly altered by RFID exposure at a whole-body specific absorption rate of 2 W/kg for 2 weeks, these changes do not necessarily indicate that RFID exposure is harmful, as they were within the normal physiological response range. Bioelectromagnetics. 39:68-76, 2018. © 2017 Wiley Periodicals, Inc.
Subject(s)
Blood Cells/radiation effects , Electromagnetic Fields/adverse effects , Radio Frequency Identification Device , Animals , Blood Cells/cytology , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/radiation effects , CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/radiation effects , Cell Count , Erythrocytes/cytology , Erythrocytes/radiation effects , Male , Rats , Rats, Sprague-Dawley , Whole-Body Irradiation/adverse effectsABSTRACT
BACKGROUND: Olfactory loss is highly prevalent, and comorbid mood disorders are common. Considering olfactory input is highly interconnected with the limbic system, and that the limbic system manages mood, it is predictable that impairments in the sense of smell may result in mood changes. METHODOLOGY: Chronic olfactory deficits were induced by repeated intranasal irrigation of ZnSO4 for 12 weeks in BALB/c mice. H&E staining, OMP staining, and potato chip finding test were performed to confirm olfactory loss. Tail suspension, forced swim, and splash tests were performed to evaluate depression, as well as open field, elevated plus maze tests were applied to assess anxiety. The mRNA levels of glucocorticoid receptor (GR) and corticotropin releasing hormone (CRH) were measured by real-time PCR to confirm relevant molecular changes. RESULTS: Disruption of the olfactory epithelium and olfactory loss was confirmed in histological studies and potato chip finding test. Behavioral tests show that the chronic anosmic state caused increased depression and reduced anxiety. PCR data showed that mRNA levels of GR in the hypothalamus and CRH in the amygdala were significantly decreased. CONCLUSIONS: These results propose that ZnSO4-induced chronic anosmia can cause a depressive and anxiolytic state via decreased hypothalamic GR and amygdalar CRH.
Subject(s)
Amygdala/metabolism , Anxiety/metabolism , Depression/etiology , Hypothalamus/metabolism , Olfaction Disorders/psychology , Animals , Corticotropin-Releasing Hormone/metabolism , Depression/metabolism , Disease Models, Animal , Male , Mice, Inbred BALB C , Olfaction Disorders/metabolism , Olfaction Disorders/pathology , Olfactory Mucosa/pathology , Random Allocation , Receptors, Glucocorticoid/metabolism , Zinc SulfateABSTRACT
In this study, we investigated the molecular mechanisms underlying the anti-proliferative effects of Compound K, with specific reference to histone modification. Exposure of HT-29 human colon cancer cells to Compound K resulted in time-dependent inhibition of histone deacetylase (HDAC) activity, mRNA and protein expression. Compound K treatment induced unmethylation of the RUNX3 promoter region such as TSA treatment and an accumulation of acetylated histones H3 and H4 within the total cellular chromatin, resulting in an enhanced ability of these histones to bind to the promoter sequences of the tumor suppressor gene Runt-related transcription factor 3 (RUNX3). Treatment of cells with Compound K increased the mRNA and protein expression of RUNX3, as well as p21, a downstream target of RUNX3. These alterations were consistent with cell cycle arrest at the G0/G1 phases and induction of apoptosis. Our results provide new insights into the mechanisms of Compound K action in human colorectal cancer cells and suggest that HDAC inhibition presents a novel approach to prevent or treat colorectal cancer.
Subject(s)
Apoptosis/drug effects , Colorectal Neoplasms/drug therapy , Ginsenosides/pharmacology , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylases/metabolism , Acetylation/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Core Binding Factor Alpha 3 Subunit/genetics , Core Binding Factor Alpha 3 Subunit/metabolism , Cyclin-Dependent Kinase Inhibitor p21/genetics , DNA-Binding Proteins/metabolism , G1 Phase Cell Cycle Checkpoints/drug effects , Gene Expression Regulation, Neoplastic/drug effects , HT29 Cells , Histone Deacetylases/drug effects , Histones/metabolism , Humans , Hydroxamic Acids/pharmacology , Panax , Promoter Regions, Genetic/drug effects , Promoter Regions, Genetic/genetics , Protein Binding/drug effects , RNA, Messenger/biosynthesisABSTRACT
Phosphatidylcholine (PPC) and sodium deoxycholate (DC) injections have been used cosmetically to reduce localized fat, but to date, few studies have addressed the histological effect of human fat tissue following injections of PPC and DC. We injected PPC and DC mixed with normal saline into the patient's abdominal area. Examinations of postinjection tissue revealed marked changes within the subcutaneous fat. We observed important microscopic evidence of substitution of fat by fibrosis, marked inflammatory infiltration with microabscess formation in the dermis, and septal and lobular panniculitis with thick fibrous septa. Fat necrosis with microcalcification and cyst formation were observed in the subcutaneous fat. Fibroid necrosis with extravasation was noted in the small vessels around fat necrosis. Therefore, careful use of PPC and DC is recommended when patients want to cosmetically reduce localized fat.
Subject(s)
Adipose Tissue/pathology , Deoxycholic Acid/adverse effects , Phosphatidylcholines/adverse effects , Adult , Deoxycholic Acid/therapeutic use , Female , Fibrosis/chemically induced , Humans , Mesotherapy/adverse effects , Necrosis/chemically induced , Obesity, Abdominal/therapy , Panniculitis/chemically induced , Phosphatidylcholines/therapeutic useABSTRACT
Previously, we reported that 20-O-(ß-D-gluco-pyranosyl)-20(S)-protopanaxadiol (Compound K, a meta-bolite of ginseng saponin) induces mitochondria-dependent and caspase-dependent apoptosis in HT-29 human colon cancer cells via the generation of reactive oxygen species. The aim of the present study was to elucidate the mechanism underlying apoptosis induced by Compound K with respect to endoplasmic reticulum (ER) stress in HT-29 cells. In the present study, Compound K induced apoptotic cell death as confirmed by DNA fragmentation and apoptotic sub-G1 cell population. Compound K also induced ER stress as indicated by staining with ER tracker, cytosolic and mitochondrial Ca2+ overloading, phosphorylation of protein-kinase-like endoplasmic reticulum kinase (PERK), phosphorylation of eukaryotic initiation factor-2α (eIF-2α), phosphorylation of IRE-1, splicing of ER stress-specific X-box transcription factor-1 (XBP-1), cleavage of activating transcription factor-6 (ATF-6), upregulation of glucose-regulated protein-78 (GRP-78/BiP) and CCAAT/enhancer-binding protein-homologous protein (CHOP), and cleavage of caspase-12. Furthermore, downregulation of CHOP expression using siCHOP RNA attenuated Compound K-induced apoptosis. Taken together, these results support the important role of ER stress response in mediating Compound K-induced apoptosis in human colon cancer cells.
Subject(s)
Apoptosis/drug effects , Colonic Neoplasms/genetics , Endoplasmic Reticulum Stress/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Sapogenins/administration & dosage , Caspase 12/genetics , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , DNA Fragmentation/drug effects , DNA-Binding Proteins/genetics , HT29 Cells , Humans , Panax/chemistry , Regulatory Factor X Transcription Factors , Transcription Factor CHOP/genetics , Transcription Factors/genetics , X-Box Binding Protein 1ABSTRACT
This study investigated the mechanisms underlying the cytotoxicity of the green algae Ulva fasciata Delile. U. fasciata extract (UFE) inhibited the growth of HCT 116 human colon cancer cells by 50% at a concentration of 200 µg/ml. In addition, UFE stimulated the production of intracellular reactive oxygen species, an effect that was abolished by pretreatment with N-acetyl cysteine, which also inhibited the cytotoxic effects of UFE. UFE also induced morphological changes indicative of apoptosis, such as the formation of apoptotic bodies, DNA fragmentation, an increase in the population of apoptotic sub-G(1) phase cells, and mitochondrial membrane depolarization. Concomitant activation of the mitochondria-dependent apoptotic pathway occurred via modulation of Bax and Bcl-2 expression, resulting in disruption of the mitochondrial membrane potential and activation of caspase-9 and caspase-3. This is the first report to demonstrate the cytotoxic effect of U. fasciata on human colon cancer cells and to provide a possible mechanism for this activity.
Subject(s)
Apoptosis/drug effects , Colonic Neoplasms/drug therapy , Plant Extracts/pharmacology , Ulva/chemistry , Acetylcysteine/pharmacology , DNA Fragmentation/drug effects , HCT116 Cells , Humans , Mitochondrial Membranes/drug effects , Plant Extracts/antagonists & inhibitors , Reactive Oxygen Species/metabolismABSTRACT
The extracts of earth worms, Eisenia andrei, have been used as a therapeutic agent for stroke in the traditional medicine. It is also reported that the protease fraction separated from the extracts has strong anti-thrombotic activity. Besides anti-thrombotic actions, we found that SP-8203, N-[3-(2,4-dioxo-1,4-dihydro-2H-quinazolin-3-yl)propyl]-N-{4-[3-(2,4-dioxo-1,4-dihydro-2H-quinazolin-3-yl)propylamino]butyl}acetamide, derived from the extracts of earth worms blocked N-methyl-(D)-aspartate (NMDA) receptor-mediated excitotoxicity in a competitive manner. The neuroprotective effects of SP-8203 were attributable to prevention of Ca(2+) influx through NMDA receptors. The systemic administration of SP-8203 markedly reduced neuronal death following middle cerebral artery occlusion in rats. SP-8203 significantly improved spatial learning and memory in the water maze test. These results provided strong pharmacological basis for its potential therapeutic roles in cerebral ischemia.
Subject(s)
Brain Injuries/prevention & control , Brain Ischemia/prevention & control , Cognition Disorders/prevention & control , Neuroprotective Agents/therapeutic use , Quinazolinones/therapeutic use , Receptors, N-Methyl-D-Aspartate/physiology , Acetamides , Animals , Animals, Newborn , Brain Injuries/metabolism , Brain Ischemia/metabolism , Cells, Cultured , Cognition Disorders/metabolism , Dose-Response Relationship, Drug , Male , Mice , Mice, Inbred ICR , N-Methylaspartate/antagonists & inhibitors , N-Methylaspartate/toxicity , Neuroprotective Agents/pharmacology , Quinazolinones/pharmacology , Rats , Rats, Wistar , Receptors, N-Methyl-D-Aspartate/agonistsABSTRACT
Genetic modification of hematopoietic stem cells holds great promise in the treatment of hematopoietic disorders. However, clinical application of gene delivery has been limited, in part, by low gene transfer efficiency. To overcome this problem, we investigated the effect of retronectin (RN) on lentiviral-mediated gene delivery into hematopoietic progenitor cells (HPCs) derived from bone marrow both in vitro and in vivo. RN has been shown to enhance transduction by promoting colocalization of lentivirus and target cells. We found that RN enhanced lentiviral transfer of the VENUS transgene into cultured c-Kit(+) Lin(-) HPCs. As a complementary approach, in vivo gene delivery was performed by subjecting mice to intra-bone marrow injection of lentivirus or a mixture of RN and lentivirus. We found that co-injection with RN increased the number of VENUS-expressing c-Kit(+) Lin(-) HPCs in bone marrow by 2-fold. Further analysis of VENUS expression in colony-forming cells from the bone marrow of these animals revealed that RN increased gene delivery among these cells by 4-fold. In conclusion, RN is effective in enhancing lentivirus-mediated gene delivery into HPCs.
Subject(s)
Fibronectins/pharmacology , Gene Transfer Techniques , Hematopoietic Stem Cells/drug effects , Lentivirus/genetics , Recombinant Proteins/pharmacology , Animals , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Cells, Cultured , Drug Evaluation, Preclinical , Fibronectins/chemistry , Hematopoietic Stem Cells/metabolism , Humans , Lentivirus/physiology , Mice , Mice, Inbred C57BL , Multipotent Stem Cells/drug effects , Multipotent Stem Cells/metabolism , Peptide Fragments/pharmacology , Protein Structure, Tertiary , Up-RegulationABSTRACT
In Oriental medicine, roots of Polygala tenuifolia Willdenow have been known to be an important herb that exhibits sedative effects in insomnia, palpitation with anxiety, restlessness, and disorientation in humans. We previously reported that BT-11, extracted from those roots, improved scopolamine-induced amnesia in rats and inhibited acetylcholinesterase activities in vitro. Therefore, we proposed that BT-11 could remedy stress-induced memory deficits in rats. In this study, the stress-induced memory impairments in rats were significantly reversed almost to the control level by BT-11 treatment. To seek an active component of BT-11 that plays an important role in antipsychotic effects, we compared BT-11 with 3,4,5-trimethoxycinnamic acid (TMCA), which is a constituent of those root extracts. However, the effects of TMCA were less or were not consistent with those of BT-11 in some of tests. In particular, BT-11 reversed the stress-induced reduction of glucose utilization by [(18)fluorodeoxyglucose]FDG-PET and the levels of neural cell adhesion molecule (NCAM) in rat brains to the control levels, whereas TMCA did not. Therefore, BT-11 improved stress-induced memory impairments through increment of glucose utilization and total NCAM levels in rat brains. In conclusion, BT-11 may be strongly effective against stress-induced amnesia in rats, through the combined effects of TMCA and other active components of BT-11.
Subject(s)
Brain/metabolism , Glucose/metabolism , Memory Disorders/drug therapy , Neural Cell Adhesion Molecules/metabolism , Phytotherapy/methods , Polygala/chemistry , Animals , Avoidance Learning/drug effects , Brain/diagnostic imaging , Brain/drug effects , Cyclohexylamines/therapeutic use , Disease Models, Animal , Exploratory Behavior/drug effects , Fluorodeoxyglucose F18/metabolism , Maze Learning/drug effects , Memory Disorders/etiology , Memory Disorders/pathology , Memory Disorders/physiopathology , Positron-Emission Tomography/methods , Rats , Rats, Wistar , Stress, Psychological/complicationsABSTRACT
Neuroligin-1 is a potent trigger for the de novo formation of synaptic connections, and it has recently been suggested that it is required for the maturation of functionally competent excitatory synapses. Despite evidence for the role of neuroligin-1 in specifying excitatory synapses, the underlying molecular mechanisms and physiological consequences that neuroligin-1 may have at mature synapses of normal adult animals remain unknown. By silencing endogenous neuroligin-1 acutely in the amygdala of live behaving animals, we have found that neuroligin-1 is required for the storage of associative fear memory. Subsequent cellular physiological studies showed that suppression of neuroligin-1 reduces NMDA receptor-mediated currents and prevents the expression of long-term potentiation without affecting basal synaptic connectivity at the thalamo-amygdala pathway. These results indicate that persistent expression of neuroligin-1 is required for the maintenance of NMDAR-mediated synaptic transmission, which enables normal development of synaptic plasticity and long-term memory in the amygdala of adult animals.
Subject(s)
Amygdala/metabolism , Fear/physiology , Long-Term Potentiation , Membrane Proteins/metabolism , Memory/physiology , Nerve Tissue Proteins/metabolism , Amygdala/cytology , Animals , Cell Adhesion Molecules, Neuronal , Ion Channel Gating , Male , Membrane Proteins/deficiency , Nerve Tissue Proteins/deficiency , Pyramidal Cells/metabolism , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/metabolism , Synaptic Transmission , Thalamus/metabolismABSTRACT
We carried out this study to search a new active constituent that had cognitive enhancing activity and low side effects from natural source. We found that the extract of dried root of Polygala tenuifolia Willdenow (BT-11, 10 mg/kg, i.p.) could significantly reverse scopolamine-induced cognitive impairments in rat, using a passive avoidance and a water maze test. We also investigated the effects of BT-11 on neurotoxicity induced by glutamate (Glu) and toxic metabolites of amyloid precursor protein (APP) such as amyloid beta protein (A beta) and C-terminal fragment of APP (CT) in primary cultured neurons of rat. The pretreatment of BT-11 (0.5, 3, and 5 micro g/ml) significantly reduced cell death induced by Glu (1 mM), A beta (10 micro M) and CT105 (10 micro M) in a dose-dependent manner. In addition, BT-11 inhibited acetylcholinesterase (AChE) activity in a dose-dependent and non-competitive manner (IC(50) value; 263.7 micro g/ml). Our novel findings suggest the possibility that this extract may have some protective effects against neuronal death and cognitive impairments in Alzheimer's disease (AD), or other neurodegenerative diseases related to excitotoxicity and central cholinergic dysfunction.