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Dimitrova T, Hristova E, Petrova N. Low-Dose Ionizing Radiation Exposure on Human Male Gametes: Damage or Benefit. Life (Basel) 2024; 14:830. [PMID: 39063584 PMCID: PMC11277789 DOI: 10.3390/life14070830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 06/24/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024] Open
Abstract
With the improvement of medical devices for diagnosis and radiotherapy, concerns about the effects of low doses of ionizing radiation are also growing. There is no consensus among scientists on whether they might have beneficial effects on humans in certain cases or pose more risks, making the exposure unreasonable. While the damaging consequences of high-dose radiation have been known since the discovery of radioactivity, low-dose effects present a much bigger investigative challenge. They are highly specific and include radio-adaptive responses, bystander effects, and genomic instability. Current data regarding the consequences of exposure to low-dose radiation on the quality of male gametes and fertility potential are contradictory. The reports suggest two directions: indirect impact on male gametes-through spermatogenesis-or direct effects at low doses on already mature spermatozoa. Although mature gametes are used for observation in both models, they are fundamentally different, leading to varied results. Due to their unique physiological characteristics, in certain cases, exposure of spermatozoa to low-dose ionizing radiation could have positive effects. Despite the findings indicating no beneficial effects of low-dose exposure on male fertility, it is essential to research its impact on mature spermatozoa, as well.
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Affiliation(s)
- Tsvetomira Dimitrova
- Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (T.D.); (N.P.)
- Invitro OB Medical Center “Dimitrov”, 1750 Sofia, Bulgaria
| | - Elena Hristova
- Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (T.D.); (N.P.)
| | - Nadya Petrova
- Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (T.D.); (N.P.)
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2
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Calabrese EJ, Selby PB. Comet assay and hormesis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 341:122929. [PMID: 37979647 DOI: 10.1016/j.envpol.2023.122929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/06/2023] [Accepted: 11/11/2023] [Indexed: 11/20/2023]
Abstract
The paper provides the first assessment of the occurrence of hormetic dose responses using the Comet assay, a genotoxic assay. Using a priori evaluative criteria based on the Hormetic Database on peer-reviewed comet assay experimental findings, numerous examples of hormetic dose responses were obtained. These responses occurred in a large and diverse range of cell types and for agents from a broad range of chemical classes. Limited attempts were made to estimate the frequency of hormesis within comet assay experimental studies using a priori entry and evaluative criteria, with results suggesting a frequency in the 40% range. These findings are important as they show that a wide range of genotoxic chemicals display evidence that is strongly suggestive of hormetic dose responses. These findings have significant implications for study design issues, including the number of doses selected, dose range and spacing. Likewise, the widespread occurrence of hormetic dose responses in this genotoxic assay has important risk assessment implications.
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Affiliation(s)
- Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA, 01003, USA.
| | - Paul B Selby
- Retired from Oak Ridge National Laboratory at Oak Ridge, TN. Home Address: 4088 Nottinghill Gate Road, Upper Arlington, OH, 43220, USA.
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Berdowska I, Matusiewicz M, Fecka I. Methylglyoxal in Cardiometabolic Disorders: Routes Leading to Pathology Counterbalanced by Treatment Strategies. Molecules 2023; 28:7742. [PMID: 38067472 PMCID: PMC10708463 DOI: 10.3390/molecules28237742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/13/2023] [Accepted: 11/21/2023] [Indexed: 12/18/2023] Open
Abstract
Methylglyoxal (MGO) is the major compound belonging to reactive carbonyl species (RCS) responsible for the generation of advanced glycation end products (AGEs). Its upregulation, followed by deleterious effects at the cellular and systemic levels, is associated with metabolic disturbances (hyperglycemia/hyperinsulinemia/insulin resistance/hyperlipidemia/inflammatory processes/carbonyl stress/oxidative stress/hypoxia). Therefore, it is implicated in a variety of disorders, including metabolic syndrome, diabetes mellitus, and cardiovascular diseases. In this review, an interplay between pathways leading to MGO generation and scavenging is addressed in regard to this system's impairment in pathology. The issues associated with mechanistic MGO involvement in pathological processes, as well as the discussion on its possible causative role in cardiometabolic diseases, are enclosed. Finally, the main strategies aimed at MGO and its AGEs downregulation with respect to cardiometabolic disorders treatment are addressed. Potential glycation inhibitors and MGO scavengers are discussed, as well as the mechanisms of their action.
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Affiliation(s)
- Izabela Berdowska
- Department of Medical Biochemistry, Wroclaw Medical University, 50-368 Wroclaw, Poland;
| | | | - Izabela Fecka
- Department of Pharmacognosy and Herbal Medicines, Wroclaw Medical University, 50-556 Wroclaw, Poland
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Sun T, Ji C, Li F, Wu H. Hormetic dose responses induced by organic flame retardants in aquatic animals: Occurrence and quantification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153295. [PMID: 35065129 DOI: 10.1016/j.scitotenv.2022.153295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/15/2022] [Accepted: 01/17/2022] [Indexed: 06/14/2023]
Abstract
The organic flame retardants (OFRs) have attracted global concerns due to their potential toxicity and ubiquitous presence in the aquatic environment. Hormesis refers to a biphasic dose response, characterized by low-dose stimulation and high-dose inhibition. The present study provided substantial evidence for the widespread occurrence of OFRs-induced hormesis in aquatic animals, including 202 hormetic dose response relationships. The maximum stimulatory response (MAX) was commonly lower than 160% of the control response, with a combined value of 134%. Furthermore, the magnitude of MAX varied significantly among multiple factors and their interactions, such as chemical types and taxonomic groups. Moreover, the distance from the dose of MAX to the no-observed-adverse-effect-level (NOAEL) (NOAEL: MAX) was typically below 10-fold (median = 6-fold), while the width of the hormetic zone (from the lowest dose inducing hormesis to the NOAEL) was approximately 20-fold. Collectively, the quantitative features of OFRs-induced hormesis in aquatic animals were in accordance with the broader hormetic literature. In addition, the implications of hormetic dose response model for the risk assessment of OFRs were discussed. This study offered a novel insight for understanding the biological effects of low-to-high doses of OFRs on aquatic animals and assessing the potential risks of OFRs in the aquatic environment.
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Affiliation(s)
- Tao Sun
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Chenglong Ji
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, PR China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences (CAS), Qingdao 266071, PR China
| | - Fei Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences (CAS), Qingdao 266071, PR China
| | - Huifeng Wu
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai 264003, PR China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences (CAS), Qingdao 266071, PR China.
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5
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Shahbaz SK, Koushki K, Sathyapalan T, Majeed M, Sahebkar A. PLGA-Based Curcumin Delivery System: An Interesting Therapeutic Approach in the Treatment of Alzheimer's Disease. Curr Neuropharmacol 2022; 20:309-323. [PMID: 34429054 PMCID: PMC9413791 DOI: 10.2174/1570159x19666210823103020] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 06/23/2021] [Accepted: 07/24/2021] [Indexed: 11/22/2022] Open
Abstract
Progressive degeneration and dysfunction of the nervous system because of oxidative stress, aggregations of misfolded proteins, and neuroinflammation are the key pathological features of neurodegenerative diseases. Alzheimer's disease is a chronic neurodegenerative disorder driven by uncontrolled extracellular deposition of β-amyloid (Aβ) in the amyloid plaques and intracellular accumulation of hyperphosphorylated tau protein. Curcumin is a hydrophobic polyphenol with noticeable neuroprotective and anti-inflammatory effects that can cross the blood-brain barrier. Therefore, it is widely studied for the alleviation of inflammatory and neurological disorders. However, the clinical application of curcumin is limited due to its low aqueous solubility and bioavailability. Recently, nano-based curcumin delivery systems are developed to overcome these limitations effectively. This review article discusses the effects and potential mechanisms of curcumin-loaded PLGA nanoparticles in Alzheimer's disease.
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Affiliation(s)
- Sanaz Keshavarz Shahbaz
- Cellular and Molecular Research Center, Research Institute for Prevention of Non-Communicable Disease, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Khadijeh Koushki
- Hepatitis Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran
| | - Thozhukat Sathyapalan
- Department of Academic Diabetes, Endocrinology and Metabolism, Hull York Medical School, University of Hull, Hull HU3 2JZ, UK
| | | | - Amirhossein Sahebkar
- BARUiotechnol Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- School of Medicine, The University of Western Australia, Perth, Australia
- School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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6
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Skaperda Z, Tekos F, Vardakas P, Nepka C, Kouretas D. Reconceptualization of Hormetic Responses in the Frame of Redox Toxicology. Int J Mol Sci 2021; 23:ijms23010049. [PMID: 35008472 PMCID: PMC8744777 DOI: 10.3390/ijms23010049] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/13/2021] [Accepted: 12/17/2021] [Indexed: 02/01/2023] Open
Abstract
Cellular adaptive mechanisms emerging after exposure to low levels of toxic agents or stressful stimuli comprise an important biological feature that has gained considerable scientific interest. Investigations of low-dose exposures to diverse chemical compounds signify the non-linear mode of action in the exposed cell or organism at such dose levels in contrast to the classic detrimental effects induced at higher ones, a phenomenon usually referred to as hormesis. The resulting phenotype is a beneficial effect that tests our physiology within the limits of our homeostatic adaptations. Therefore, doses below the region of adverse responses are of particular interest and are specified as the hormetic gain zone. The manifestation of redox adaptations aiming to prevent from disturbances of redox homeostasis represent an area of particular interest in hormetic responses, observed after exposure not only to stressors but also to compounds of natural origin, such as phytochemicals. Findings from previous studies on several agents demonstrate the heterogeneity of the specific zone in terms of the molecular events occurring. Major factors deeply involved in these biphasic phenomena are the bioactive compound per se, the dose level, the duration of exposure, the cell, tissue or even organ exposed to and, of course, the biomarker examined. In the end, the molecular fate is a complex toxicological event, based on beneficial and detrimental effects, which, however, are poorly understood to date.
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Affiliation(s)
- Zoi Skaperda
- Laboratory of Animal Physiology, Department of Biochemistry-Biotechnology, School of Health Sciences, University of Thessaly, 41500 Larissa, Greece; (Z.S.); (F.T.); (P.V.)
| | - Fotios Tekos
- Laboratory of Animal Physiology, Department of Biochemistry-Biotechnology, School of Health Sciences, University of Thessaly, 41500 Larissa, Greece; (Z.S.); (F.T.); (P.V.)
| | - Periklis Vardakas
- Laboratory of Animal Physiology, Department of Biochemistry-Biotechnology, School of Health Sciences, University of Thessaly, 41500 Larissa, Greece; (Z.S.); (F.T.); (P.V.)
| | - Charitini Nepka
- Department of Pathology, University Hospital of Larissa, 41334 Larissa, Greece;
| | - Demetrios Kouretas
- Laboratory of Animal Physiology, Department of Biochemistry-Biotechnology, School of Health Sciences, University of Thessaly, 41500 Larissa, Greece; (Z.S.); (F.T.); (P.V.)
- Correspondence: ; Tel.: +30-2410-565-277; Fax: +30-2410-565-293
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Oronsky B, Guo X, Wang X, Cabrales P, Sher D, Cannizzo L, Wardle B, Abrouk N, Lybeck M, Caroen S, Oronsky A, Reid TR. Discovery of RRx-001, a Myc and CD47 Downregulating Small Molecule with Tumor Targeted Cytotoxicity and Healthy Tissue Cytoprotective Properties in Clinical Development. J Med Chem 2021; 64:7261-7271. [PMID: 34043360 DOI: 10.1021/acs.jmedchem.1c00599] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
After extensive screening of aerospace compounds in an effort to source a novel anticancer agent, RRx-001, a first-in-class dinitroazetidine small molecule, was selected for advancement into preclinical and clinical development. RRx-001 is a minimally toxic small molecule with a distinct chemical structure and mechanism of action. The paradox of RRx-001 is that it mediates both antitumor cytotoxicity and normal tissue protection. The question of exactly how RRx-001 does this, and by means of what mechanism(s), depending on the route of delivery, intravenous or intratumoral, are explored. RRx-001 is currently in phase 2 and 3 clinical trials for the treatment of multiple solid tumor malignancies and as a supportive care drug.
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Affiliation(s)
- Bryan Oronsky
- EpicentRx Inc., 11099 North Torrey Pines Road, Suite 160, La Jolla, California 92037, United States
| | - XiaoNing Guo
- SciClone Pharmaceuticals Co., Ltd., 22 Floor, Shanghai Central Plaza, No. 381 Middle Huaihai Road, Huangpu, Shanghai 200020, China
| | - XiaoHui Wang
- SciClone Pharmaceuticals Co., Ltd., 22 Floor, Shanghai Central Plaza, No. 381 Middle Huaihai Road, Huangpu, Shanghai 200020, China
| | - Pedro Cabrales
- Department of Bioengineering, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States
| | - David Sher
- Department of Radiation Oncology, UT Southwestern Medical Center, 2280 Inwood Road, Dallas, Texas 75390, United States
| | - Lou Cannizzo
- Department of Space Systems, Northrop Grumman Corporation, 2980 Fairview Park Drive, Falls Church, Virginia 22042, United States
| | - Bob Wardle
- Department of Space Systems, Northrop Grumman Corporation, 2980 Fairview Park Drive, Falls Church, Virginia 22042, United States
| | - Nacer Abrouk
- EpicentRx Inc., 11099 North Torrey Pines Road, Suite 160, La Jolla, California 92037, United States
| | - Michelle Lybeck
- EpicentRx Inc., 11099 North Torrey Pines Road, Suite 160, La Jolla, California 92037, United States
| | - Scott Caroen
- EpicentRx Inc., 11099 North Torrey Pines Road, Suite 160, La Jolla, California 92037, United States
| | - Arnold Oronsky
- InterWest Partners, 467 First Street, Suite 201, Los Altos, California 94022, United States
| | - Tony R Reid
- EpicentRx Inc., 11099 North Torrey Pines Road, Suite 160, La Jolla, California 92037, United States
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Agathokleous E, Saitanis C, Markouizou A. Hormesis Shifts the No-Observed-Adverse-Effect Level (NOAEL). Dose Response 2021; 19:15593258211001667. [PMID: 33815016 PMCID: PMC7995310 DOI: 10.1177/15593258211001667] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/16/2021] [Accepted: 02/17/2021] [Indexed: 11/15/2022] Open
Abstract
Data from recent dose-response toxicological studies suggest that the no-observed-adverse-effect-level (NOAEL) may depend upon whether hormesis is present. A further examination of these data supports this hypothesis by showing that the NOAEL was greater for living units (organisms or cells) showing hormesis than for living units showing no hormesis. For example, some cancer tissue cells may exhibit hormetic responses to an anticancer drug while some other cancer tissue cells may not. These findings suggest that living units showing hormesis may also be less susceptible than living units not showing hormesis. However, these findings are preliminary and cannot be generalized or assumed to be a norm yet. New studies are needed to evaluate how NOAEL shifts depending on the occurrence of hormesis.
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Affiliation(s)
- Evgenios Agathokleous
- Key Laboratory of Agrometeorology of Jiangsu Province, School of Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing, China
| | - Costas Saitanis
- Lab of Ecology and Environmental Science, Agricultural University of Athens, Athens, Greece
| | - Athina Markouizou
- Department of Radiation Oncology, Metaxa Cancer Hospital, Piraeus, Greece
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Oakley PA, Harrison DE. Radiophobic Fear-Mongering, Misappropriation of Medical References and Dismissing Relevant Data Forms the False Stance for Advocating Against the Use of Routine and Repeat Radiography in Chiropractic and Manual Therapy. Dose Response 2021; 19:1559325820984626. [PMID: 33628151 PMCID: PMC7883173 DOI: 10.1177/1559325820984626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/04/2020] [Accepted: 12/05/2020] [Indexed: 12/14/2022] Open
Abstract
There is a faction within the chiropractic profession passionately advocating against the routine use of X-rays in the diagnosis, treatment and management of patients with spinal disorders (aka subluxation). These activists reiterate common false statements such as "there is no evidence" for biomechanical spine assessment by X-ray, "there are no guidelines" supporting routine imaging, and also promulgate the reiterating narrative that "X-rays are dangerous." These arguments come in the form of recycled allopathic "red flag only" medical guidelines for spine care, opinion pieces and consensus statements. Herein, we review these common arguments and present compelling data refuting such claims. It quickly becomes evident that these statements are false. They are based on cherry-picked medical references and, most importantly, expansive evidence against this narrative continues to be ignored. Factually, there is considerable evidential support for routine use of radiological imaging in chiropractic and manual therapies for 3 main purposes: 1. To assess spinopelvic biomechanical parameters; 2. To screen for relative and absolute contraindications; 3. To reassess a patient's progress from some forms of spine altering treatments. Finally, and most importantly, we summarize why the long-held notion of carcinogenicity from X-rays is not a valid argument.
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Kim S, Wand J, Magana-Ramirez C, Fraij J. Logistic Regression Models with Unspecified Low Dose-Response Relationships and Experimental Designs for Hormesis Studies. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2021; 41:92-109. [PMID: 32885437 DOI: 10.1111/risa.13588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 02/18/2020] [Accepted: 08/22/2020] [Indexed: 06/11/2023]
Abstract
Hormesis refers to a nonmonotonic (biphasic) dose-response relationship in toxicology, environmental science, and related fields. In the presence of hormesis, a low dose of a toxic agent may have a lower risk than the risk at the control dose, and the risk may increase at high doses. When the sample size is small due to practical, logistic, and ethical considerations, a parametric model may provide an efficient approach to hypothesis testing at the cost of adopting a strong assumption, which is not guaranteed to be true. In this article, we first consider alternative parameterizations based on the traditional three-parameter logistic regression. The new parameterizations attempt to provide robustness to model misspecification by allowing an unspecified dose-response relationship between the control dose and the first nonzero experimental dose. We then consider experimental designs including the uniform design (the same sample size per dose group) and the c -optimal design (minimizing the standard error of an estimator for a parameter of interest). Our simulation studies showed that (1) the c -optimal design under the traditional three-parameter logistic regression does not help reducing an inflated Type I error rate due to model misspecification, (2) it is helpful under the new parameterization with three parameters (Type I error rate is close to a fixed significance level), and (3) the new parameterization with four parameters and the c -optimal design does not reduce statistical power much while preserving the Type I error rate at a fixed significance level.
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Affiliation(s)
- Steven Kim
- Department of Mathematics and Statistics, California State University, Monterey Bay, Seaside, CA, USA
| | - Jeffrey Wand
- Department of Mathematics and Statistics, California State University, Monterey Bay, Seaside, CA, USA
| | - Christina Magana-Ramirez
- Department of Mathematics and Statistics, California State University, Monterey Bay, Seaside, CA, USA
| | - Jenel Fraij
- Department of Mathematics, Hartnell College, Salinas, CA, USA
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Oakley PA, Harrison DE. Are Continued Efforts to Reduce Radiation Exposures from X-Rays Warranted? Dose Response 2021; 19:1559325821995653. [PMID: 33746654 PMCID: PMC7903835 DOI: 10.1177/1559325821995653] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/23/2021] [Accepted: 01/23/2021] [Indexed: 12/12/2022] Open
Abstract
There are pressures to avoid use of radiological imaging throughout all healthcare due to the notion that all radiation is carcinogenic. This perception stems from the long-standing use of the linear no-threshold (LNT) assumption of risk associated with radiation exposures. This societal perception has led to relentless efforts to avoid and reduce radiation exposures to patients at great costs. Many radiation reduction campaigns have been launched to dissuade doctors from using radiation imaging. Lower-dose imaging techniques and practices are being advocated. Alternate imaging procedures are encouraged. Are these efforts warranted? Based on recent evidence, LNT ideology is shown to be defunct for risk assessment at low-dose exposure ranges which includes X-rays and CT scans. In fact, the best evidence that was once used to support LNT ideology, including the Life Span Study data, now indicates thresholds for cancer induction are high; therefore, low-dose X-rays cannot cause harm. Current practices are safe as exposures currently encountered are orders of magnitude below threshold levels shown to be harmful. As long as imaging is medically warranted, it is shown that efforts to reduce exposures that are within background radiation levels and that are also shown to enhance health by upregulating natural adaptive protection systems are definitively wasted resources.
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Oakley PA, Harrison DE. X-Ray Hesitancy: Patients' Radiophobic Concerns Over Medical X-rays. Dose Response 2020; 18:1559325820959542. [PMID: 32994755 PMCID: PMC7503016 DOI: 10.1177/1559325820959542] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/20/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022] Open
Abstract
All too often the family physician, orthopedic surgeon, dentist or chiropractor is met with radiophobic concerns about X-ray imaging in the clinical setting. These concerns, however, are unwarranted fears based on common but ill-informed and perpetuated ideology versus current understanding of the effects of low-dose radiation exposures. Themes of X-ray hesitancy come in 3 forms: 1. All radiation exposures are harmful (i.e. carcinogenic); 2. Radiation exposures are cumulative; 3. Children are more susceptible to radiation. Herein we address these concerns and find that low-dose radiation activates the body's adaptive responses and leads to reduced cancers. Low-dose radiation is not cumulative as long as enough time (e.g. 24 hrs) passes prior to a repeated exposure, and any damage is repaired, removed, or eliminated. Children have more active immune systems; the literature shows children are no more affected than adults by radiation exposures. Medical X-rays present a small, insignificant addition to background radiation exposure that is not likely to cause harm. Doctors and patients alike should be better informed of the lack of risks from diagnostic radiation and the decision to image should rely on the best evidence, unique needs of the patient, and the expertise of the physician-not radiophobia.
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Barbosa RJ, Ratti da Silva G, Cola IM, Kuchler JC, Coelho N, Barboza LN, Menetrier JV, de Souza R, Zonta FN, Froehlich DL, Jacomassi E, Soares AA, Velasques LG, Veiga ADA, Souza LMD, Lovato ECW, Ribeiro-Paes JT, Gasparotto Junior A, Acco A, Lívero FADR. Promising therapeutic use of Baccharis trimera (less.) DC. as a natural hepatoprotective agent against hepatic lesions that are caused by multiple risk factors. JOURNAL OF ETHNOPHARMACOLOGY 2020; 254:112729. [PMID: 32145332 DOI: 10.1016/j.jep.2020.112729] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 02/03/2020] [Accepted: 02/29/2020] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Baccharis trimera (Less.) DC is a perennial subshrub, popularly known as "carqueja," that belongs to the Asteraceae family. Ethnobotanical studies indicate that this species is used for the treatment of diabetes and digestive and liver diseases. However, studies that sought to validate its popular use were conducted using ethanolic extracts of the plant, which does not reflect the ethnomedicinal use of this species in humans. AIM OF THE STUDY Non-alcoholic fatty liver disease (NAFLD) is characterized by triglyceride accumulation in the liver that can progress to cirrhosis and hepatocellular carcinoma. Because of the severity of this disease, less toxic and more effective therapeutic agents need to be developed. B. trimera may be a promising therapeutic alternative, but its activity against multiple risk factors for liver disease (e.g., smoking, dyslipidemia, and diabetes mellitus) has not been studied. The present study investigated the effects of an ethnomedicinal form of a B. trimera preparation in a rat model of NAFLD that is associated with multiple risk factors. MATERIAL AND METHODS Phytochemical analysis of the ethanolic soluble fraction of B. trimera extract was performed using ultra-performance liquid chromatography coupled to high-resolution mass spectrometry. Streptozotocin was used to induce diabetes in male Wistar rats. The rats received a 0.5% cholesterol-enriched diet and were exposed to cigarette smoke (9 cigarettes/day, 5 days/week, for 4 weeks). In the last 2 weeks, the animals were orally treated with vehicle (negative control group), B. trimera extract (30, 100, and 300 mg/kg), or insulin + simvastatin. One group of rats that was not exposed to these risk factors was also evaluated. Blood was collected for glucose, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) analysis. The liver and feces were collected for lipid quantification. The liver was additionally processed for histopathological analysis. RESULTS The model successfully induced NAFLD and increased levels of glucose, AST, and ALT in the negative control group. Treatment with the B. trimera extract (30 and 100 mg/kg) and insulin + simvastatin decreased hepatic and fecal lipids. In contrast to insulin + simvastatin treatment, all three doses of B. trimera effectively reduced AST and ALT levels. CONCLUSION B. trimera may be promising as a hepatoprotective agent against hepatic lesions that are caused by multiple risk factors.
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Affiliation(s)
- Rodrigo Jachimowski Barbosa
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Gustavo Ratti da Silva
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Itaruã Machri Cola
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | | | - Natalia Coelho
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Lorena Neris Barboza
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Jacqueline Vergutz Menetrier
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Ronaldo de Souza
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | | | | | - Ezilda Jacomassi
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Andréia Assunção Soares
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Leonardo Garcia Velasques
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | - Alan de Almeida Veiga
- Institute of Research Pelé Pequeno Príncipe, Pequeno Príncipe Faculty, Curitiba, PR, Brazil
| | - Lauro Mera de Souza
- Institute of Research Pelé Pequeno Príncipe, Pequeno Príncipe Faculty, Curitiba, PR, Brazil
| | - Evellyn Claudia Wietzkoski Lovato
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil
| | | | - Arquimedes Gasparotto Junior
- Laboratory of Electrophysiology and Cardiovascular Pharmacology, Faculty of Health Sciences, Federal University of Grande Dourados, Dourados, MS, Brazil.
| | - Alexandra Acco
- Laboratory of Pharmacology and Metabolism, Post-Graduate Program of Pharmacology, Federal University of Paraná, Curitiba, PR, Brazil
| | - Francislaine Aparecida Dos Reis Lívero
- Laboratory of Preclinical Research of Natural Products, Post-Graduate Program in Medicinal Plants and Phytotherapeutics in Basic Attention, Paranaense University, Umuarama, PR, Brazil.
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Schalkwijk CG, Stehouwer CDA. Methylglyoxal, a Highly Reactive Dicarbonyl Compound, in Diabetes, Its Vascular Complications, and Other Age-Related Diseases. Physiol Rev 2020; 100:407-461. [DOI: 10.1152/physrev.00001.2019] [Citation(s) in RCA: 176] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The formation and accumulation of methylglyoxal (MGO), a highly reactive dicarbonyl compound, has been implicated in the pathogenesis of type 2 diabetes, vascular complications of diabetes, and several other age-related chronic inflammatory diseases such as cardiovascular disease, cancer, and disorders of the central nervous system. MGO is mainly formed as a byproduct of glycolysis and, under physiological circumstances, detoxified by the glyoxalase system. MGO is the major precursor of nonenzymatic glycation of proteins and DNA, subsequently leading to the formation of advanced glycation end products (AGEs). MGO and MGO-derived AGEs can impact on organs and tissues affecting their functions and structure. In this review we summarize the formation of MGO, the detoxification of MGO by the glyoxalase system, and the biochemical pathways through which MGO is linked to the development of diabetes, vascular complications of diabetes, and other age-related diseases. Although interventions to treat MGO-associated complications are not yet available in the clinical setting, several strategies to lower MGO have been developed over the years. We will summarize several new directions to target MGO stress including glyoxalase inducers and MGO scavengers. Targeting MGO burden may provide new therapeutic applications to mitigate diseases in which MGO plays a crucial role.
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Affiliation(s)
- C. G. Schalkwijk
- CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands; and Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - C. D. A. Stehouwer
- CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre, Maastricht, The Netherlands; and Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
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Aoishi Y, Yoshimasu T, Oura S, Kawago M, Hirai Y, Miyasaka M, Ohashi T, Nishimura Y. Quantitative Evaluation of Hormesis in Breast Cancer Using Histoculture Drug Response Assay. Dose Response 2019; 17:1559325819896183. [PMID: 31903070 PMCID: PMC6933548 DOI: 10.1177/1559325819896183] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 11/16/2022] Open
Abstract
Purpose Hormesis is a phenomenon of growth stimulation at low doses and inhibition at higher doses. In cancer treatment, little is known about how hormesis affects cancer cell proliferation. We evaluated the hormetic dose-response relationship of paclitaxel using surgically resected breast cancer specimens on the basis of histoculture drug response assay (HDRA). Methods We used surgically resected fresh tumor specimens from 22 patients with breast cancer: 17 invasive ductal, 3 mucinous, and 2 other "special-type" cancers. All patients were female, ranging in age between 40 and 86 (median 60) years. Small pieces of viable cancer tissue were placed on collagen gel and cultured for 7 days with paclitaxel. Inhibition rates of paclitaxel at several concentrations were measured and fitted to a sigmoid dose-response curve. Results Hormesis was observed in 9 of the 22 cases; ED50 of cytotoxic effect was significantly higher (P = .0036) in hormesis (H) group (44.6 ± 4.2 µg/mL) than in nonhormesis (N) group (26.7 ± 3.5 μg/mL). Conclusion We evaluated hormesis in breast cancer tissue using HDRA for the first time although previously confirmed in cultured cells. Hormesis seems to occur in patients undergoing treatment with anticancer agents, especially in a metastatic setting. Meanwhile, tumor growth may be stimulated in patients who are resistant to paclitaxel.
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Affiliation(s)
- Yuka Aoishi
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Tatsuya Yoshimasu
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Shoji Oura
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Mitsumasa Kawago
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Yoshimitsu Hirai
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Miwako Miyasaka
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Takuya Ohashi
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
| | - Yoshiharu Nishimura
- Department of Thoracic and Cardiovascular Surgery, Wakayama Medical University, Wakayama, Japan
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Oakley PA, Ehsani NN, Harrison DE. Repeat Radiography in Monitoring Structural Changes in the Treatment of Spinal Disorders in Chiropractic and Manual Medicine Practice: Evidence and Safety. Dose Response 2019; 17:1559325819891043. [PMID: 31839759 PMCID: PMC6900628 DOI: 10.1177/1559325819891043] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/24/2019] [Accepted: 10/29/2019] [Indexed: 12/18/2022] Open
Abstract
There is substantial evidence for normal relationships between spine and postural parameters, as measured from radiographs of standing patients. Sagittal balance, cervical lordosis, thoracic kyphosis, lumbar lordosis, pelvic tilt, and the more complex understanding of the interrelations between these essential components of normal stance have evolved to where there are known, established thresholds for normalcy. These spinal parameters are reliably measured from X-ray images and serve as goals of care in the treatment of spine and postural disorders. Initial and follow-up spinal imaging by X-ray is thus crucial for the practice of contemporary and evidence-based structural rehabilitation. Recent studies have demonstrated that improvement in the spine and posture by nonsurgical methods offers superior long-term patient outcomes versus conventional methods that only temporarily treat pain/dysfunction. Low-dose radiation from repeated X-ray imaging in treating subluxated patients is substantially below the known threshold for harm and is within background radiation exposures. Since alternative imaging methods are not clinically practical at this time, plain radiography remains the standard for spinal imaging. It is safe when used in a repeated fashion for quantifying pre-post spine and postural subluxation and deformity patterns in the practice of structural correction methods by chiropractic and other manual medicine practices.
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Fonseca TG, Carriço T, Fernandes E, Abessa DMS, Tavares A, Bebianno MJ. Impacts of in vivo and in vitro exposures to tamoxifen: Comparative effects on human cells and marine organisms. ENVIRONMENT INTERNATIONAL 2019; 129:256-272. [PMID: 31146160 DOI: 10.1016/j.envint.2019.05.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 05/06/2019] [Indexed: 06/09/2023]
Abstract
Tamoxifen (TAM) is a first generation-SERM administered for hormone receptor-positive (HER+) breast cancer in both pre- and post-menopausal patients and may undergo metabolic activation in organisms that share similar receptors and thus face comparable mechanisms of response. The present study aimed to assess whether environmental trace concentrations of TAM are bioavailable to the filter feeder M. galloprovincialis (100 ng L-1) and to the deposit feeder N. diversicolor (0.5, 10, 25 and 100 ng L-1) after 14 days of exposure. Behavioural impairment (burrowing kinetic), neurotoxicity (AChE activity), endocrine disruption by alkali-labile phosphate (ALP) content, oxidative stress (SOD, CAT, GPXs activities), biotransformation (GST activity), oxidative damage (LPO) and genotoxicity (DNA damage) were assessed. Moreover, this study also pertained to compare TAM cytotoxicity effects to mussels and targeted human (i.e. immortalized retinal pigment epithelium - RPE; and human transformed endothelial cells - HeLa) cell lines, in a range of concentrations from 0.5 ng L-1 to 50 μg L-1. In polychaetes N. diversicolor, TAM exerted remarkable oxidative stress and damage at the lowest concentration (0.5 ng L-1), whereas significant genotoxicity was reported at the highest exposure level (100 ng L-1). In mussels M. galloprovincialis, 100 ng L-1 TAM caused endocrine disruption in males, neurotoxicity, and an induction in GST activity and LPO byproducts in gills, corroborating in genotoxicity over the exposure days. Although cytotoxicity assays conducted with mussel haemocytes following in vivo exposure was not effective, in vitro exposure showed to be a feasible alternative, with comparable sensitivity to human cell line (HeLa).
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Affiliation(s)
- T G Fonseca
- CIMA, Centro de Investigação Marinha e Ambiental, Universidade do Algarve, Campus Gambelas, 8005-135 Faro, Portugal; NEPEA, Núcleo de Estudos em Poluição e Ecotoxicologia, Aquática, Universidade Estadual Paulista (UNESP), Campus do Litoral Paulista, São Vicente, SP 11330-900, Brazil
| | - T Carriço
- CIMA, Centro de Investigação Marinha e Ambiental, Universidade do Algarve, Campus Gambelas, 8005-135 Faro, Portugal
| | - E Fernandes
- CIMA, Centro de Investigação Marinha e Ambiental, Universidade do Algarve, Campus Gambelas, 8005-135 Faro, Portugal
| | - D M S Abessa
- NEPEA, Núcleo de Estudos em Poluição e Ecotoxicologia, Aquática, Universidade Estadual Paulista (UNESP), Campus do Litoral Paulista, São Vicente, SP 11330-900, Brazil
| | - A Tavares
- Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, Campus Gambelas, 8005-135 Faro, Portugal
| | - M J Bebianno
- CIMA, Centro de Investigação Marinha e Ambiental, Universidade do Algarve, Campus Gambelas, 8005-135 Faro, Portugal.
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Moghaddam NSA, Oskouie MN, Butler AE, Petit PX, Barreto GE, Sahebkar A. Hormetic effects of curcumin: What is the evidence? J Cell Physiol 2018; 234:10060-10071. [PMID: 30515809 DOI: 10.1002/jcp.27880] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 11/15/2018] [Indexed: 12/26/2022]
Abstract
Curcumin (diferuloylmethane), a component of the yellow powder prepared from the roots of Curcuma longa or Zingiberaceae (known as turmeric) is not only widely used to color and flavor food but also used as a pharmaceutical agent. Curcumin demonstrates anti-inflammatory, anticarcinogenic, antiaging, and antioxidant activity, as well as efficacy in wound healing. Notably, curcumin is a hormetic agent (hormetin), as it is stimulatory at low doses and inhibitory at high doses. Hormesis by curcumin could be also a particular function at low doses (i.e., antioxidant behavior) and another function at high dose (i.e., induction of autophagy and cell death). Recent findings suggest that curcumin exhibits biphasic dose-responses on cells, with low doses having stronger effects than high doses; examples being activation of the mitogen-activated protein kinase signaling pathway or antioxidant activity. This indicates that many effects induced by curcumin are dependent on dose and some effects might be greater at lower doses, indicative of a hormetic response. Despite the consistent occurrence of hormetic responses of curcumin in a wide range of biomedical models, epidemiological and clinical trials are needed to assess the nature of curcumin's dose-response in humans. Fortunately, more than one hundred clinical trials with curcumin and curcumin derivatives are ongoing. In this review, we provide the first comprehensive analysis supportive of the hormetic behavior of curcumin and curcumin derivatives.
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Affiliation(s)
| | - Mohammad Nosrati Oskouie
- Department of Clinical Nutrition and Dietetics, Faculty of Nutrition and Food Technology, National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Alexandra E Butler
- Diabetes Research Center, Qatar Biomedical Research Institute, Doha, Qatar
| | - Patrice X Petit
- CNRS FR3636 Institut de Neurosciences "Mitochondria, Apoptosis and Autophagy Signalling," Université Paris-Descartes, Paris, France
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia.,Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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Oakley PA, Harrison DE. Radiophobia: 7 Reasons Why Radiography Used in Spine and Posture Rehabilitation Should Not Be Feared or Avoided. Dose Response 2018; 16:1559325818781445. [PMID: 30013456 PMCID: PMC6043928 DOI: 10.1177/1559325818781445] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/04/2018] [Accepted: 05/15/2018] [Indexed: 12/21/2022] Open
Abstract
Evidence-based contemporary spinal rehabilitation often requires radiography. Use of radiography (X-rays or computed tomography scans) should not be feared, avoided, or have their exposures lessened to decrease patient dose possibly jeopardizing image quality. This is because all fears of radiation exposures from medical diagnostic imaging are based on complete fabrication of health risks based on an outdated, invalid linear model that has simply been propagated for decades. We present 7 main arguments for continued use of radiography for routine use in spinal rehabilitation: (1) the linear no-threshold model for radiation risk estimates is invalid for low-dose exposures; (2) low-dose radiation enhances health via the body's adaptive response mechanisms (ie, radiation hormesis); (3) an X-ray with low-dose radiation only induces 1 one-millionth the amount of cellular damage as compared to breathing air for a day; (4) radiography is below inescapable natural annual background radiation levels; (5) radiophobia stems from unwarranted fears and false beliefs; (6) radiography use leads to better patient outcomes; (7) the risk to benefit ratio is always beneficial for routine radiography. Radiography is a safe imaging method for routine use in patient assessment, screening, diagnosis, and biomechanical analysis and for monitoring treatment progress in daily clinical practice.
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Silva-Palacios A, Ostolga-Chavarría M, Buelna-Chontal M, Garibay C, Hernández-Reséndiz S, Roldán FJ, Flores PL, Luna-López A, Königsberg M, Zazueta C. 3-NP-induced Huntington's-like disease impairs Nrf2 activation without loss of cardiac function in aged rats. Exp Gerontol 2017. [PMID: 28624355 DOI: 10.1016/j.exger.2017.06.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Cardiovascular diseases (CVDs) are one of the leading causes of death in patients over 60years with Huntington's disease (HD). Here, we investigated if age-related oxidative stress (OS) is a relevant factor to develop cardiac damage in an in vivo model of striatal neurodegeneration induced by 3-nitropropionic acid (3-NP). We also evaluated the potential effect of tert-butylhydroquinone (tBHQ) to increase the Nrf2-regulated antioxidant response in hearts from adult and aged rats intoxicated with 3-NP. Our results showed that 3-NP-treatment did not induce cardiac dysfunction, neither in adult nor in aged rats. However, at the cellular level, adult animals showed higher susceptibility to 3-NP-induced damage than aged rats, which suggest that chronic oxidative stress ongoing during aging might have induced an hormetic response that probably prevented from further 3-NP damage. We also found that the oxidative unbalance concurs with unresponsiveness of the Nrf2-mediated antioxidant response in old animals.
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Affiliation(s)
- A Silva-Palacios
- Departamento de Biomedicina Cardiovascular, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico; Departamento de Ciencias de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, Mexico; Programa de Posgrado en Biología Experimental, Departamento de Ciencias de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, Mexico
| | - M Ostolga-Chavarría
- Departamento de Biomedicina Cardiovascular, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico
| | - M Buelna-Chontal
- Departamento de Biomedicina Cardiovascular, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico
| | - C Garibay
- Departamento de Neuropatología, Instituto Nacional de Neurología y Neurocirugía, Manuel Velasco Suárez, Mexico
| | - S Hernández-Reséndiz
- Departamento de Biomedicina Cardiovascular, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico
| | - F J Roldán
- Departamento de Ecocardiografía, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico
| | - P L Flores
- Departamento de Instrumentación Electromecánica, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico
| | - A Luna-López
- Departamento de Ciencias Básicas, Instituto Nacional de Geriatría, Mexico
| | - M Königsberg
- Departamento de Ciencias de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, Mexico
| | - C Zazueta
- Departamento de Biomedicina Cardiovascular, Instituto Nacional de Cardiología, Ignacio Chávez, Mexico.
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Mushak P. Temporal stability of chemical hormesis (CH): Is CH just a temporary stop on the road to thresholds and toxic responses? THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 569-570:1446-1456. [PMID: 27396315 DOI: 10.1016/j.scitotenv.2016.06.233] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 06/23/2016] [Accepted: 06/29/2016] [Indexed: 06/06/2023]
Abstract
Chemical hormesis (CH) is currently described as a nonmonotonic, bidirectional dose-response relationship for chemicals, where a stimulatory, (beneficial?) response at low dose or exposure is followed by an inhibitory response at higher doses/exposures (or vice-versa). CH is depicted as U(J)-shaped or inverse U(J)-shaped curves, i.e., curve slopes change sign. Some describe CH as a homeostasis-preserving response; others view CH as adaptive or (pre)conditioning responses to chemical stress. One aspect of CH and stress hormesis in general that has not been researched is its temporal stability, i.e., persistence, particularly in experimental animals and humans having long-term chemical stressing. Once maximized, does the CH response remain operative over the entire time of chemical exposure? One possible reason for the question's neglect is that temporal stability, e.g., 'steady-state hormesis,' has been assumed. Another is that CH temporality is not well understood or has been under-appreciated as to its importance. Available data, mainly for simpler biological systems, describe cases of transitory CH. Other examples, in human and experimental animal studies, show transitory existence of CH and, in some specialized cases, persisting CH. Also, certain disease state-induced hormetic responses are transitory over time in humans. The question requires resolution if CH is to be considered (i) a stable and beneficial or adverse response, (ii) a stable dose-response model competitive with stable threshold and linear, nonthreshold (LNT) dose-response models, and (iii) a model having any impact on, or role in, regulatory and public health policies.
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Affiliation(s)
- Paul Mushak
- PB Associates, 4036 Nottaway Road, Durham, NC, USA.
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Di YL, Cong ML, Zhang R, Zhu FX. Hormetic Effects of Trifloxystrobin on Aggressiveness of Sclerotinia sclerotiorum. PLANT DISEASE 2016; 100:2113-2118. [PMID: 30682995 DOI: 10.1094/pdis-03-16-0403-re] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Sclerotinia sclerotiorum is a devastating ascomycete plant pathogen with an extremely wide host range. Fungicides are still the mainstay for control of this pathogen, and stimulations to mycelial growth and aggressiveness by subtoxic doses of fungicides carbendazim and dimethachlon have been reported. The present study assessed hormetic effects of the quinone outside inhibitor (QoI) fungicide trifloxystrobin on aggressiveness of S. sclerotiorum. Trifloxystrobin at 0.0001, 0.0005, and 0.001 μg/ml exerted significant stimulatory effects on aggressiveness to potted rapeseed plants, and the highest percent stimulation were 20.5 and 24.2% for isolates HB15 and SX11, respectively. At 18 h postinoculation (HPI), initial necrotic lesions were visible to the naked eye on leaves treated with trifloxystrobin, whereas no obvious disease symptoms were discerned for the nontreated control. At 24, 36, and 48 HPI, aggressiveness stimulation was more obvious than at 18 HPI. Scanning electron microscopic observations demonstrated that no mycelia were detected on the nontreated leaves at 4 HPI; by contrast, mycelia were observed on leaves treated with trifloxystrobin at 0.0001 μg/ml. At 8 and 12 HPI, there were more mycelia and infecting hyphae on the treated leaves than on the nontreated control. These results indicated that fungal stimulation had occurred in the first 4 and 8 HPI, suggesting that direct stimulation was likely to be the underlying mechanism for hormetic actions of trifloxystrobin. Pretreatment with trifloxystrobin did not significantly affect subsequent mycelial growth on PDA or aggressiveness to detached rapeseed leaves in the absence of trifloxystrobin. However, in the presence of trifloxystrobin, mycelial growth and aggressiveness were significantly (P < 0.05) greater for the pretreatment with trifloxystrobin at 0.003 and 0.03 μg/ml compared with the nonpretreatment control, indicating that a prior exposure to the fungicide may undermine its subsequent effectiveness. These studies will raise our awareness of fungicide hormesis and have important implications for judicious application of fungicides.
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Affiliation(s)
- Ya-Li Di
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Meng-Long Cong
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Ran Zhang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Fu-Xing Zhu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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Ng CYP, Pereira S, Cheng SH, Adam-Guillermin C, Garnier-Laplace J, Yu KN. Combined effects of alpha particles and depleted uranium on Zebrafish (Danio rerio) embryos. JOURNAL OF RADIATION RESEARCH 2016; 57:343-55. [PMID: 26937024 PMCID: PMC4973638 DOI: 10.1093/jrr/rrv104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/11/2015] [Indexed: 05/04/2023]
Abstract
The combined effects of low-dose or high-dose alpha particles and depleted uranium (DU) in Zebrafish (Danio rerio) embryos were studied. Three schemes were examined-(i) [ILUL]: 0.44 mGy alpha-particle dose + 10 µg/l DU exposure, (ii) [IHUH]: 4.4 mGy alpha-particle dose + 100 µg/l DU exposure and (iii) [IHUL]: 4.4 mGy alpha-particle dose + 10 µg/l DU exposure-in which Zebrafish embryos were irradiated with alpha particles at 5 h post fertilization (hpf) and/or exposed to uranium at 5-6 hpf. The results were also compared with our previous work, which studied the effects of [ILUH]: 0.44 mGy alpha-particle dose + 100 µg/l DU exposure. When the Zebrafish embryos developed to 24 hpf, the apoptotic signals in the entire embryos, used as the biological endpoint for this study, were quantified. Our results showed that [ILUL] and [IHUL] led to antagonistic effects, whereas [IHUH] led to an additive effect. The effect found for the previously studied case of [ILUH] was difficult to define because it was synergistic with reference to the 100 µg/l DU exposure, but it was antagonistic with reference to the 0.44 mGy alpha-particle dose. All the findings regarding the four different schemes showed that the combined effects critically depended on the dose response to each individual stressor. We also qualitatively explained these findings in terms of promotion of early death of cells predisposed to spontaneous transformation by alpha particles, interacting with the delay in cell death resulting from various concentrations of DU exposure.
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Affiliation(s)
- Candy Y P Ng
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong
| | - Sandrine Pereira
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul Lez Durance, 13115, France
| | - Shuk Han Cheng
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
| | - Christelle Adam-Guillermin
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul Lez Durance, 13115, France
| | - Jacqueline Garnier-Laplace
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS, Cadarache, St Paul Lez Durance, 13115, France
| | - Kwan Ngok Yu
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
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Sandbichler AM, Höckner M. Cadmium Protection Strategies--A Hidden Trade-Off? Int J Mol Sci 2016; 17:ijms17010139. [PMID: 26805823 PMCID: PMC4730378 DOI: 10.3390/ijms17010139] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 12/12/2022] Open
Abstract
Cadmium (Cd) is a non-essential transition metal which is introduced into the biosphere by various anthropogenic activities. Environmental pollution with Cd poses a major health risk and Cd toxicity has been extensively researched over the past decades. This review aims at changing the perspective by discussing protection mechanisms available to counteract a Cd insult. Antioxidants, induction of antioxidant enzymes, and complexation of Cd to glutathione (GSH) and metallothionein (MT) are the most potent protective measures to cope with Cd-induced oxidative stress. Furthermore, protection mechanisms include prevention of endoplasmic reticulum (ER) stress, mitophagy and metabolic stress, as well as expression of chaperones. Pre-exposure to Cd itself, or co-exposure to other metals or trace elements can improve viability under Cd exposure and cells have means to reduce Cd uptake and improve Cd removal. Finally, environmental factors have negative or positive effects on Cd toxicity. Most protection mechanisms aim at preventing cellular damage. However, this might not be possible without trade-offs like an increased risk of carcinogenesis.
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Affiliation(s)
| | - Martina Höckner
- University of Innsbruck, Institute of Zoology, Technikerstraße 25, 6020 Innsbruck, Austria.
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Ng CYP, Pereira S, Cheng SH, Adam-Guillermin C, Garnier-Laplace J, Yu KN. Combined effects of depleted uranium and ionising radiation on zebrafish embryos. RADIATION PROTECTION DOSIMETRY 2015; 167:311-315. [PMID: 25948823 DOI: 10.1093/rpd/ncv269] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In the environment, living organisms are exposed to a mixture of stressors, and the combined effects are deemed as multiple stressor effects. In the present work, the authors studied the multiple stressor effect in embryos of the zebrafish (Danio rerio) from simultaneous exposure to alpha particles and depleted uranium (DU) through quantification of apoptotic signals at 24 h post-fertilisation (hpf) revealed by vital dye acridine orange staining. In each set of experiments, dechorionated zebrafish embryos were divided into 4 groups, each having 10 embryos: Group (C) in which the embryos did not receive any further treatment; Group (IU) in which the embryos received an alpha-particle dose of 0.44 mGy at 5 hpf and were then exposed to 100 µg l(-1) of DU from 5 to 6 hpf; Group (I) in which the embryos received an alpha-particle dose of 0.44 mGy at 5 hpf and Group (U) in which the dechorionated embryos were exposed to 100 µg l(-1) of DU from 5 to 6 hpf. The authors confirmed that an alpha-particle dose of 0.44 mGy and a DU exposure for 1 h separately led to hormetic and toxic effects assessed by counting apoptotic signals, respectively, in the zebrafish. Interestingly, the combined exposure led to an effect more toxic than that caused by the DU exposure alone, so effectively DU changed the beneficial effect (hormesis) brought about by alpha-particle irradiation into an apparently toxic effect. This could be explained in terms of the promotion of early death of cells predisposed to spontaneous transformation by the small alpha-particle dose (i.e. hormetic effect) and the postponement of cell death upon DU exposure.
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Affiliation(s)
- C Y P Ng
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong
| | - S Pereira
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul Lez Durance 13115, France
| | - S H Cheng
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
| | - C Adam-Guillermin
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul Lez Durance 13115, France
| | - J Garnier-Laplace
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS, Cadarache, St Paul Lez Durance 13115, France
| | - K N Yu
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong
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Chattopadhyay D, Sen S, Chatterjee R, Roy D, James J, Thirumurugan K. Context- and dose-dependent modulatory effects of naringenin on survival and development of Drosophila melanogaster. Biogerontology 2015; 17:383-93. [PMID: 26520643 DOI: 10.1007/s10522-015-9624-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Accepted: 10/28/2015] [Indexed: 12/19/2022]
Abstract
Naringenin, the predominant bioflavonoid found in grapefruit and tomato has diverse bioactive properties that encompass anti-carcinogenic, anti-inflammatory, anti-atherogenic, anti-estrogenic, anti-hyperlipidemic and anti-hyperglycemic characteristics. Naringenin has not been explored for its pro-longevity traits in fruit flies. Therefore, the current study explores its influence on longevity, fecundity, feeding rate, larval development, resistance to starvation stress and body weight in male and female wild-type Drosophila melanogaster Canton-S flies. Flies were fed with normal and high fat diets respectively. The results implied hormetic effects of naringenin on longevity and development in flies. In flies fed with standard and high fat diets, lower concentrations of naringenin (200 and 400 µM) augmented mean lifespan while higher concentrations (600 and 800 µM) were consistently lethal. However, enhanced longevity seen at 400 µM of naringenin was at the expense of reduced fecundity and food intake in flies. Larvae reared on standard diet having 200 µM of naringenin exhibited elevated pupation and emergence as flies. Eclosion time was hastened in larvae reared on standard diet having 200 µM of naringenin. Female flies fed with a standard diet having 200 and 400 µM of naringenin were more resistant to starvation stress. Reduction in body weight was observed in male and female flies fed with a high fat diet supplemented with 200 and 400 µM of naringenin respectively. Collectively, the results elucidated a context- and dose-dependent hormetic efficacy of naringenin that varied with gender, diet and stage of lifecycle in flies.
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Affiliation(s)
- Debarati Chattopadhyay
- 206, Structural Biology Lab, Centre for Biomedical Research, VIT University, Vellore, Tamil Nadu, India
| | - Soumadeep Sen
- 206, Structural Biology Lab, Centre for Biomedical Research, VIT University, Vellore, Tamil Nadu, India
| | - Rishita Chatterjee
- 206, Structural Biology Lab, Centre for Biomedical Research, VIT University, Vellore, Tamil Nadu, India
| | - Debasish Roy
- 206, Structural Biology Lab, Centre for Biomedical Research, VIT University, Vellore, Tamil Nadu, India
| | - Joel James
- 206, Structural Biology Lab, Centre for Biomedical Research, VIT University, Vellore, Tamil Nadu, India
| | - Kavitha Thirumurugan
- 206, Structural Biology Lab, Centre for Biomedical Research, VIT University, Vellore, Tamil Nadu, India.
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Di YL, Zhu ZQ, Lu XM, Zhu FX. Pathogenicity Stimulation of Sclerotinia sclerotiorum by Subtoxic Doses of Carbendazim. PLANT DISEASE 2015; 99:1342-1346. [PMID: 30690992 DOI: 10.1094/pdis-02-15-0161-re] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Sclerotinia sclerotiorum is a devastating ascomycete fungus capable of infecting more than 400 species of plants worldwide. Carbendazim has been a principal fungicide for control of this pathogen and high levels of carbendazim resistance have been reported in eastern China. In this study, stimulatory effect of subtoxic doses of carbendazim on pathogenicity of S. sclerotiorum was investigated. All seven field resistant isolates with EC50 values greater than 1,000 μg/ml exhibited stimulated pathogenicity toward detached leaves of rapeseed at subtoxic concentrations of carbendazim. Detailed studies on pathogenicity of two resistant isolates AH-17 and LJ-86 toward potted rapeseed plants and detached leaves demonstrated that carbendazim at 0.2 to 5 μg/ml could consistently stimulate significantly higher (P < 0.05) pathogenicity than the control. On potted rapeseed plants, the percent stimulations on pathogenicity ranged from 18.8 to 22.0% for isolate AH-17 and from 15.1 to 23.2% for isolate LJ-86. On detached leaves of rapeseed, the percent stimulations ranged from 18.7 to 31.29% for isolate AH-17 and from 16.7 to 24.3% for isolate LJ-86. Studies on stimulation mechanism indicated that secretion of oxalic acid and tolerance to oxidative stresses H2O2 and paraquat after exposed to subtoxic doses of carbendazim did not change significantly. These results have profound implications for judicious application of fungicides and sustainable management of fungicide resistance.
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Affiliation(s)
- Ya-Li Di
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zu-Qing Zhu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Xiao-Ming Lu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Fu-Xing Zhu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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Devos A, Dallas LJ, Voiseux C, Lecomte-Pradines C, Jha AN, Fiévet B. Assessment of growth, genotoxic responses and expression of stress related genes in the Pacific oyster Crassostrea gigas following chronic exposure to ionizing radiation. MARINE POLLUTION BULLETIN 2015; 95:688-698. [PMID: 25843441 DOI: 10.1016/j.marpolbul.2015.03.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 03/06/2015] [Accepted: 03/21/2015] [Indexed: 06/04/2023]
Abstract
Marine organisms are exposed to low doses of anthropogenic contaminants during their entire life. Authorized amounts of radionuclides are discharged in the Channel by nuclear facilities. The Pacific oyster was used to investigate the potential impact of chronic exposure to ionizing radiation. Though we exposed larvae and spat for two weeks to much higher concentrations than those encountered near nuclear facilities, oyster growth and expression of 9 selected stress genes were not significantly changed. To determine potential DNA damage, 2year old oysters were exposed for two weeks to tritiated water. The comet assay was used to evaluate the level of DNA strand breaks in haemocytes, whilst the 'clearance rate' was used as a measure of physiological effects. Whilst other parameters did not alter, DNA damage significantly increased. Our results highlight the significance of the observed DNA damage and their potential consequences at higher levels of biological organization.
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Affiliation(s)
- Alexandre Devos
- Institut de Radioprotection et de Sûreté Nucléaire, PRP-ENV/SERIS/Laboratoire de Radioécologie de Cherbourg-Octeville, Rue Max Pol Fouchet, BP 10, 50130 Cherbourg Octeville, France
| | - Lorna J Dallas
- University of Plymouth, School of Biological Sciences, Plymouth PL4 8AA, United Kingdom
| | - Claire Voiseux
- Institut de Radioprotection et de Sûreté Nucléaire, PRP-ENV/SERIS/Laboratoire de Radioécologie de Cherbourg-Octeville, Rue Max Pol Fouchet, BP 10, 50130 Cherbourg Octeville, France
| | - Catherine Lecomte-Pradines
- Institut de Radioprotection et de Sûreté Nucléaire, PRP-ENV/SERIS/Laboratoire d'ECOtoxicologie des radionucléides, BP 3, 13115 Saint-Paul-Lez-Durance Cedex, France
| | - Awadhesh N Jha
- University of Plymouth, School of Biological Sciences, Plymouth PL4 8AA, United Kingdom
| | - Bruno Fiévet
- Institut de Radioprotection et de Sûreté Nucléaire, PRP-ENV/SERIS/Laboratoire de Radioécologie de Cherbourg-Octeville, Rue Max Pol Fouchet, BP 10, 50130 Cherbourg Octeville, France.
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Seth I, Joiner MC, Tucker JD. Cytogenetic Low-Dose Hyperradiosensitivity Is Observed in Human Peripheral Blood Lymphocytes. Int J Radiat Oncol Biol Phys 2015; 91:82-90. [DOI: 10.1016/j.ijrobp.2014.09.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 09/11/2014] [Accepted: 09/13/2014] [Indexed: 10/24/2022]
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Luna–López A, González-Puertos VY, López-Diazguerrero NE, Königsberg M. New considerations on hormetic response against oxidative stress. J Cell Commun Signal 2014; 8:323-31. [PMID: 25284448 PMCID: PMC4390794 DOI: 10.1007/s12079-014-0248-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 09/30/2014] [Indexed: 01/06/2023] Open
Abstract
In order to survive living organisms have developed multiple mechanisms to deal with tough environmental conditions. Hormesis is defined as a process in which exposure to a low dose of a chemical agent or environmental factor that is damaging at higher doses induces an adaptive beneficial effect on the cell or organism. In this paper, we examine several ideas that might be taken into consideration before using hormesis as a therapeutic tool to improve health and life span, and hopefully will open the discussion for new and interesting debates regard hormesis. The first one is to understand that the same stressor or inductor can activate different pathways in a parallel or dual response, which might lead to diverse outcomes. Another idea is related to the mechanisms involved in activating Nrf2, which might be different and have diverse hormetic effects.Last, we discuss mild oxidative stress in association to low-grade chronic inflammation as a stimulating avenue to be explored and the unexpected effects proposed by the obesity paradox theory. All the previous might help to clarify the reasons why centenarians are able to reach the extreme limits of human life span, which could probably be related to the way they deal with homeostasis maintenance, providing an opportunity for hormesis to intervene significantly.
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Affiliation(s)
| | - Viridiana Y. González-Puertos
- />Departamento de Ciencias de la Salud, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-535, C.P 09340 México, D.F Mexico
| | - Norma E. López-Diazguerrero
- />Departamento de Ciencias de la Salud, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-535, C.P 09340 México, D.F Mexico
| | - Mina Königsberg
- />Departamento de Ciencias de la Salud, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-535, C.P 09340 México, D.F Mexico
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Zhou F, Liang HJ, Di YL, You H, Zhu FX. Stimulatory Effects of Sublethal Doses of Dimethachlon on Sclerotinia sclerotiorum. PLANT DISEASE 2014; 98:1364-1370. [PMID: 30703927 DOI: 10.1094/pdis-10-13-1059-re] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Growth and virulence stimulations of sublethal doses of fungicides on plant-pathogenic fungi and oomycetes have been reported and the stimulatory effects are potentially relevant to plant disease management. Sclerotinia sclerotiorum is one of the most devastating and economically important necrotrophic fungal phytopathogens, capable of infecting more than 400 species of plants worldwide. In order to study stimulatory effects of sublethal doses of fungicides on S. sclerotiorum, 55 dimethachlon-sensitive isolates and 3 dimethachlon-resistant isolates of S. sclerotiorum were assayed to determine effects of sublethal doses of dimethachlon on mycelial growth rate on potato dextrose agar (PDA) media and virulence on oilseed rape plants. Results showed that all 3 dimethachlon-resistant isolates and 13 of the 55 sensitive isolates exhibited stimulatory responses to sublethal doses of dimethachlon. Dimethachlon-resistant isolates grew significantly (P < 0.05) faster on PDA media amended with dimethachlon at 0.5 to 4 μg/ml than on fungicide-free PDA media. As for virulence on detached leaves of oilseed rape plants, lesion diameters of dimethachlon-resistant isolates after growth on PDA media amended with dimethachlon at 0.5 to 2 μg/ml were significantly larger (P < 0.05) than the control. The maximum stimulatory effects were 42.40 to 59.80%. In pot experiments, for both dimethachlon-sensitive and -resistant isolates, significant (P < 0.05) virulence stimulations were observed after spraying with dimethachlon at a concentration of 2 μg/ml. After growing on dimethachlon-amended PDA media, H2O2 sensitivity of S. sclerotiorum decreased significantly (P < 0.05) compared with the nonamended PDA control.
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Affiliation(s)
- Feng Zhou
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Hong-Jie Liang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Ya-Li Di
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Hong You
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Fu-Xing Zhu
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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Analysis of individual and combined effects of ochratoxin A and zearalenone on HepG2 and KK-1 cells with mathematical models. Toxins (Basel) 2014; 6:1177-92. [PMID: 24674935 PMCID: PMC4014727 DOI: 10.3390/toxins6041177] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 03/07/2014] [Accepted: 03/11/2014] [Indexed: 12/24/2022] Open
Abstract
Ochratoxin A (OTA) and Zearalenone (ZEA) are widespread mycotoxins that contaminate foodstuffs simultaneously, but sufficient data regarding their mixed toxicities are lacking. This study aims to analyze the style of combined effects of OTA and ZEA on cells of their target organs. For this purpose, cytotoxicity was determined in HepG2 and KK-1 cells treated with single and combined forms of OTA and ZEA. Furthermore, we have analyzed the data using two mathematical models based on the concepts of concentration addition (CA) and independent addition (IA). By analyzing data with nonlinear regression, toxins applied singly showed classic sigmoid dose-response curves in HepG2 cells whereas in KK-1 cells hormetic responses were observed. Exposure to equieffective mixtures of OTA and ZEA showed additive effects, irrespective of different nonlinear regression models used. Our results demonstrate that IA is an appropriate concept to account for mixture effects of OTA and ZEA. The results in ROS generation indicate a departure from additivity to antagonism or synergism at different concentrations, probably due to potential interaction during ROS production. This study shows that a risk assessment of mycotoxins should account for mixture effects, and prediction models are valuable tools for mixture assessment.
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Souza MA, Johann S, Lima LARDS, Campos FF, Mendes IC, Beraldo H, Souza-Fagundes EMD, Cisalpino PS, Rosa CA, Alves TMDA, de Sá NP, Zani CL. The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives. Mem Inst Oswaldo Cruz 2014; 108:S0074-02762013000300342. [PMID: 23778660 DOI: 10.1590/s0074-02762013000300013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 09/19/2012] [Indexed: 01/27/2023] Open
Abstract
Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes.
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Affiliation(s)
- Marina Azevêdo Souza
- Fiocruz, Centro de Pesquisas René Rachou, Laboratório de Química de Produtos Naturais, Belo Horizonte, MG, Brasil
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Mater N, Geret F, Castillo L, Faucet-Marquis V, Albasi C, Pfohl-Leszkowicz A. In vitro tests aiding ecological risk assessment of ciprofloxacin, tamoxifen and cyclophosphamide in range of concentrations released in hospital wastewater and surface water. ENVIRONMENT INTERNATIONAL 2014; 63:191-200. [PMID: 24317225 DOI: 10.1016/j.envint.2013.11.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 11/06/2013] [Accepted: 11/14/2013] [Indexed: 06/02/2023]
Abstract
Ciprofloxacin (CIP), tamoxifen (TAM) and cyclophosphamide (CP) which are often used in anticancer treatment are released in hospital effluent and into the environment. Although the concentrations are low (from ng/L to μg/L), no data exist concerning their ecotoxicological impact. In this study two biomarkers of early effect were performed on hepatic cells (HepG2): cell viability and genotoxicity (DNA breaks) using cell proliferative assay and comet assay, respectively. These data were compared with two standardized ecotoxicological tests: algaltoxkit F™ and microtox®. Cells were exposed to an increasing amount of an individual drug or in a mixture for 24, 48 or 72h. The time-exposure of bacteria and algae ranged between 5 and 30min and 72h, respectively. A non-monotonic dose-response on cell viability was observed when HepG2 cells were exposed to TAM alone or in the presence of CIP. The same scheme was observed with microtox® when the bacteria were exposed to the mixtures. On the other side, an individual drug does not induce any DNA breaks on hepatic cells, whereas a mixture leads to a dose dependent increase of DNA breaks. Similarly a positive response was observed with algaltoxkit F™ only with mixtures. Synergistic effects observed when drugs are in a mixture highlight the importance of investigating the ecotoxicological effects of contaminants at low concentrations and in mixtures.
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Affiliation(s)
- N Mater
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole Nationale Supérieure Agronomique (ENSAT), 1 avenue Agrobiopôle, BP 32607, 31320 Auzeville-Tolosane, France
| | - F Geret
- Université de Toulouse, Laboratoire GEODE, UMR CNRS 5602, Centre Universitaire Jean-François Champollion, Place de Verdun, 81012 Albi cedex 9, France
| | - L Castillo
- Veolia Environnement Recherche et Innovation, Centre de Recherche de Maisons Laffitte, 78603 Maisons Laffitte, France
| | - V Faucet-Marquis
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole Nationale Supérieure Agronomique (ENSAT), 1 avenue Agrobiopôle, BP 32607, 31320 Auzeville-Tolosane, France
| | - C Albasi
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole National Supérieure des Ingénieurs en Arts chimiques et Technologiques (ENSIACET), 4 allée Emile Monso, 31030 Toulouse cedex 4, France
| | - A Pfohl-Leszkowicz
- Université de Toulouse, Institut National Polytechnique, Laboratoire de Génie Chimique, UMR CNRS/INPT/UPS 5503, France; Ecole Nationale Supérieure Agronomique (ENSAT), 1 avenue Agrobiopôle, BP 32607, 31320 Auzeville-Tolosane, France.
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Watanabe K, Okada K, Fukabori R, Hayashi Y, Asahi K, Terawaki H, Kobayashi K, Watanabe T, Nakayama M. Methylglyoxal (MG) and cerebro-renal interaction: does long-term orally administered MG cause cognitive impairment in normal Sprague-Dawley rats? Toxins (Basel) 2014; 6:254-69. [PMID: 24402234 PMCID: PMC3920260 DOI: 10.3390/toxins6010254] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/24/2013] [Accepted: 12/31/2013] [Indexed: 11/23/2022] Open
Abstract
Methylglyoxal (MG), one of the uremic toxins, is a highly reactive alpha-dicarbonyl compound. Recent clinical studies have demonstrated the close associations of cognitive impairment (CI) with plasma MG levels and presence of kidney dysfunction. Therefore, the present study aims to examine whether MG is a direct causative substance for CI development. Eight-week-old male Sprague-Dawley (SD) rats were divided into two groups: control (n = 9) and MG group (n = 10; 0.5% MG in drinking water), and fed a normal diet for 12 months. Cognitive function was evaluated by two behavioral tests (object exploration test and radial-arm maze test) in early (4–6 months of age) and late phase (7–12 months of age). Serum MG was significantly elevated in the MG group (495.8 ± 38.1 vs. 244.8 ± 28.2 nM; p < 0.001) at the end of study. The groups did not differ in cognitive function during the course of study. No time-course differences were found in oxidative stress markers between the two groups, while, antioxidants such as glutathione peroxidase and superoxide dismutase activities were significantly increased in the MG group compared to the control. Long-term MG administration to rats with normal kidney function did not cause CI. A counter-balanced activation of the systemic anti-oxidant system may offset the toxicity of MG in this model. Pathogenetic significance of MG for CI requires further investigation.
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Affiliation(s)
- Kimio Watanabe
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Kana Okada
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Ryoji Fukabori
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Yoshimitsu Hayashi
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Koichi Asahi
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Hiroyuki Terawaki
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Kazuto Kobayashi
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Tsuyoshi Watanabe
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
| | - Masaaki Nakayama
- Department of Nephrology, Hypertension, Diabetology, Endocrinology and Metabolism, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
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Lewandowska U, Szewczyk K, Hrabec E, Janecka A, Gorlach S. Overview of metabolism and bioavailability enhancement of polyphenols. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:12183-99. [PMID: 24295170 DOI: 10.1021/jf404439b] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A proper diet is one of major factors contributing to good health and is directly related to general condition of the organism. Phenolic compounds are abundant in foods and beverages (fresh and processed fruits and vegetables, leguminous plants, cereals, herbs, spices, tea, coffee, wine, beer) and their pleiotropic biological activities result in numerous health beneficial effects. On the other hand, high reactivity and very large diversity in terms of structure and molecular weight renders polyphenols one of the most difficult groups of compounds to investigate, as evidenced by ambiguous and sometimes contradictory results of many studies. Furthermore, phenolics undergo metabolic transformations, which significantly change their biological activities. Here, we discuss some aspects of metabolism and absorption of phenolic compounds. On the basis of information reported in the literature as well as in summaries of clinical trials and patent applications, we also give an overview of strategies for enhancing their bioavailability.
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Affiliation(s)
- Urszula Lewandowska
- Department of Biomolecular Chemistry, Medical University of Lodz , Lodz, Poland
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Lewandowska U, Szewczyk K, Owczarek K, Hrabec Z, Podsędek A, Sosnowska D, Hrabec E. Procyanidins from evening primrose (Oenothera paradoxa) defatted seeds inhibit invasiveness of breast cancer cells and modulate the expression of selected genes involved in angiogenesis, metastasis, and apoptosis. Nutr Cancer 2013; 65:1219-31. [PMID: 24099118 DOI: 10.1080/01635581.2013.830314] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
There is a growing interest in plant polyphenols (including flavanols) that exhibit pleiotropic biological activities such as antiinflammatory, antioxidant, and anticancer effects. Here, we report for the first time the inhibition of MDA-MB-231 breast cancer cell viability and invasiveness by an evening primrose flavanol preparation (EPFP). We observed a decrease in MDA-MB-231 viability of 50% vs. a control after 72 h of incubation with EPFP at a concentration of 58 μM gallic acid equivalents (GAE) and an inhibition of their invasiveness of 65% vs. a control at 75 μM GAE after 48 h of incubation. EPFP caused a 10-fold reduction in matrix metalloproteinase-9 (MMP-9) activity at 100 μM GAE. Furthermore, through modulation of mRNA expression, EPFP reduced the expression levels of the following proteins: antiapoptotic Bcl-2, angiogenic vascular endothelial growth factor (VEGF), and 2 transcription factors (c-Jun, c-Fos). Moreover, analysis by flow cytometry revealed that EPFP induced apoptosis in MDA-MB-231 cells. In conclusion, our data shows that EPFP inhibits cell viability by increasing apoptosis and decreases cell invasiveness by decreasing angiogenesis.
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Affiliation(s)
- Urszula Lewandowska
- a Department of Medical Enzymology , Medical University of Lodz , Lodz , Poland
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Luna-López A, González-Puertos VY, Romero-Ontiveros J, Ventura-Gallegos JL, Zentella A, Gomez-Quiroz LE, Königsberg M. A noncanonical NF-κB pathway through the p50 subunit regulates Bcl-2 overexpression during an oxidative-conditioning hormesis response. Free Radic Biol Med 2013; 63:41-50. [PMID: 23648765 DOI: 10.1016/j.freeradbiomed.2013.04.033] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 03/27/2013] [Accepted: 04/25/2013] [Indexed: 11/30/2022]
Abstract
Cells can respond to damage and stress by activating various repair and survival pathways. One of these responses can be induced by preconditioning the cells with sublethal stress to provoke a prosurvival response that will prevent damage and death, and which is known as hormesis. Bcl-2, an antiapoptotic protein recognized by its antioxidant and prosurvival functions, has been documented to play an important role during oxidative-conditioning hormesis. Using an oxidative-hormetic model, which was previously established in the L929 cell line by subjecting the cells to a mild oxidative stress of 50 μM H₂O₂ for 9 h, we identified two different transductional mechanisms that participate in the regulation of Bcl-2 expression during the hormetic response. These mechanisms converge in activating the nuclear transcription factor NF-κB. Interestingly, the noncanonical p50 subunit of the NF-κB family is apparently the subunit that participates during the oxidative-hormetic response.
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Hoffmann GR, Moczula AV, Laterza AM, Macneil LK, Tartaglione JP. Adaptive response to hydrogen peroxide in yeast: induction, time course, and relationship to dose-response models. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2013; 54:384-396. [PMID: 23740476 DOI: 10.1002/em.21785] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2013] [Revised: 04/02/2013] [Accepted: 04/15/2013] [Indexed: 06/02/2023]
Abstract
The assay for trp5 gene conversion and ilv1-92 reversion in Saccharomyces cerevisiae strain D7 was used to characterize the induction of an adaptive response by hydrogen peroxide (H(2)O(2)). Effects of a small priming dose on the genotoxic effects of a larger challenge dose were measured in exponential cultures and in early stationary phase. An adaptive response, indicated by smaller convertant and revertant frequencies after the priming dose, occurred at lower priming and challenge doses in young, well-aerated cultures. Closely spaced priming doses from 0.000975 to 2 mM, followed by a 1 mM challenge, showed that the induction of the adaptive response is biphasic. In exponential cultures it was maximal with a priming dose of 0.125-0.25 mM. Very small priming doses were insufficient to induce the adaptive response, whereas higher doses contributed to damage. A significant adaptive response was detected when the challenge dose was administered 10-20 min after the priming exposure. It was fully expressed within 45 min, and the yeast began to return to the nonadapted state after 4-6 hr. Because of the similarity of the biphasic induction to hormetic curves and the proposal that adaptive responses are a manifestation of hormesis, we evaluated whether the low doses of H(2)O(2) that induce the adaptive response show a clear hormetic response without a subsequent challenge dose. Hormesis was not evident, but there was an apparent threshold for genotoxicity at or slightly below 0.125 mM. The results are discussed with respect to linear, threshold, and hormesis dose-response models.
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Affiliation(s)
- George R Hoffmann
- Department of Biology, College of the Holy Cross, Worcester, MA 01610-2395, USA.
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Heard PL, Rubitski EE, Spellman RA, Schuler MJ. Phenolphthalein induces centrosome amplification and tubulin depolymerization in vitro. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2013; 54:308-316. [PMID: 23677914 DOI: 10.1002/em.21781] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 03/27/2013] [Accepted: 03/26/2013] [Indexed: 06/02/2023]
Abstract
Aneuploidy is a major cause of human reproductive failure and plays a large role in cancer. Phenolphthalein (PHT) induces tumors in rodents but its primary mechanism does not seem to be DNA damage. In heterozygous TSG-p53(®) mice, PHT induces lymphomas and also micronuclei (MN), many containing kinetochores (K), implying chromosome loss (aneuploidy). The induction of aneuploidy would be compatible with the loss of the normal p53 gene seen in the lymphomas. In this study, we confirm PHT's aneugenicity and determine the aneugenic mechanism of PHT by combining traditional genetic toxicology assays with image and flow cytometry methods. The data revealed that PHT induces tubulin polymerization abnormalities and deregulates the centrosome duplication cycle causing centrosome amplification. We also show that one of the consequences of these events is apoptosis.
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Affiliation(s)
- Pamela L Heard
- Pfizer Worldwide Research and Development, Genetic Toxicology Center of Emphasis, Groton, Connecticut, USA.
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Zhao H, Joo S, Xie W, Ji X. Using hormetic strategies to improve ischemic preconditioning and postconditioning against stroke. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2013; 5:61-72. [PMID: 23750305 PMCID: PMC3669735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 04/30/2013] [Indexed: 06/02/2023]
Abstract
Both ischemic preconditioning (IPreC) and ischemic postconditioning (IPostC) trigger endogenous neuroprotective mechanisms in cerebral ischemia. IPreC is defined as a brief ischemia that protects against a subsequent severe ischemia, while IPostC refers to a series of brief cerebral blood vessel occlusions performed at reperfusion following an ischemic event. Hormesis describes a biphasic dose-response relationship in toxicology, where a low dose of toxicant stimulates and a high dose inhibits biological responses. In general, any minor stress will stimulate a biological system to generate an adaptive response; in most cases, if not all, such an adaptive response to a minor stress is beneficial to the biological system. Proponents of hormesis suggest that this effect is independent of any models, either in vivo or in vitro, from animal, plant, fungi, yeast, to bacteria, by any measurement of end points, survival ratio or time, growth, tissue repair, life span, cognition, learning and memory. In this review, we examine whether IPreC and IPostC are actually sub-forms of hormesis and whether quantitative hormetic strategies can be used to study IPreC and IPostC. By integrating the concepts of IPreC and IPostC with hormesis, we aim to broaden the avenues leading to clinical translation of IPreC and IPostC in stroke treatment.
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Affiliation(s)
- Heng Zhao
- Department of Neurosurgery, Stanford University School of MedicineStanford, CA 94305-5327, USA
| | - Sungpil Joo
- Department of Neurosurgery, Stanford University School of MedicineStanford, CA 94305-5327, USA
| | - Weiying Xie
- Department of Neurosurgery, Stanford University School of MedicineStanford, CA 94305-5327, USA
| | - Xunming Ji
- Xuanwu Hospital, Beijing Capital Medical UniversityBeijing, China
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Lewandowska U, Szewczyk K, Owczarek K, Hrabec Z, Podsędek A, Koziołkiewicz M, Hrabec E. Flavanols from evening primrose (Oenothera paradoxa) defatted seeds inhibit prostate cells invasiveness and cause changes in Bcl-2/Bax mRNA ratio. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:2987-2998. [PMID: 23451794 DOI: 10.1021/jf304269x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this study, we assessed the influence of an evening primrose flavanol preparation (EPFP) on proliferation and invasiveness of human prostate cancer cells (DU 145) and immortalized prostate epithelial cells (PNT1A). We report for the first time that EPFP reduces DU 145 cell proliferation (IC50 = 97 μM GAE for 72 h incubation) and invasiveness (by 24% versus control at 75 μM GAE). EPFP strongly inhibited PNT1A invasiveness in a concentration-dependent manner (by 67% versus control at 75 μM GAE) and did not cause a reduction in their proliferation. Furthermore, EPFP inhibited the activities of MMP-2 and MMP-9 secreted to culture medium by PNT1A cells by 84% and 34% versus control at 100 μM GAE, respectively. In the case of DU 145, MMP-9 activity at 100 μM GAE was reduced by 37% versus control. Moreover, the evening primrose seed flavanols suppressed the expression of selected genes (MMP-1, MMP-9, MMP-14, c-Fos, c-Jun, and VEGF) and also caused favorable changes in Bcl-2/Bax mRNA ratio which render DU 145 cells more sensitive to apoptosis-triggering agents. An additional confirmation of the proapoptotic activity of EPFP toward DU 145 was visualization of characteristic apoptotic bodies by DAPI staining. In conclusion, this study suggests that EPFP may increase apoptosis and reduce angiogenesis of prostate cancer cells.
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Affiliation(s)
- Urszula Lewandowska
- Department of Medical Enzymology, Medical University of Lodz , Mazowiecka 6/8, 92-215 Lodz, Poland.
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Lewandowska U, Szewczyk K, Owczarek K, Hrabec Z, Podsędek A, Koziołkiewicz M, Hrabec E. Flavanols from Japanese Quince (Chaenomeles Japonica) Fruit Inhibit Human Prostate and Breast Cancer Cell Line Invasiveness and Cause Favorable Changes inBax/Bcl-2mRNA Ratio. Nutr Cancer 2013; 65:273-85. [DOI: 10.1080/01635581.2013.749292] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Mushak P. Limits to chemical hormesis as a dose-response model in health risk assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 443:643-649. [PMID: 23220756 DOI: 10.1016/j.scitotenv.2012.11.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 11/02/2012] [Accepted: 11/05/2012] [Indexed: 06/01/2023]
Abstract
This review presents and discusses the extent to which chemical hormesis meets five important requirements for performance of any dose-response model in the toxicological and regulatory sciences. These include (1) the requirement that there be a documented and accepted mechanistic basis for the dose-response model's plausible role and use in health risk assessment; (2) the requirement that any newly proposed dose-response methodology can be compared with current models as to reliability and scientific validity; (3) the requirement that the underlying reliability and stability of the model be established as to its temporal aspects, that is, minimal temporal lag between stressor contact and biological or toxicological response and temporal stability expressed throughout the prevailing relationship; (4) the requirement that the dose-response model be as broadly applicable as other dose-response methodologies being applied in human health risk assessment; and, (5) the requirement that any dose-response model proposed as default methodology can be characterized as to variability and uncertainty and will have a minimal likelihood of harm to the health of impacted populations. This review includes a brief treatment of definitions of hormesis and its place in nonmonotonic dose-response relationships. Overall, critical evaluation of chemical hormesis as a dose-response model in risk assessment shows it to have significant limits within the five requirements. These limits will impede any acceptance of chemical hormesis as a default approach in health risk assessment.
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Affiliation(s)
- Paul Mushak
- PB Associates, 4036 Nottaway Rd., Durham, NC 27707, USA.
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Zhao H. Hurdles to clear before clinical translation of ischemic postconditioning against stroke. Transl Stroke Res 2013; 4:63-70. [PMID: 23524538 DOI: 10.1007/s12975-012-0243-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Ischemic postconditioning has been established for its protective effects against stroke in animal models. It is performed after post-stroke reperfusion and refers to a series of induced ischemia or a single brief one. This review article addresses major hurdles in clinical translation of ischemic postconditioning to stroke patients, including potential hazards, the lack of well-defined protective paradigms, and the paucity of deeply-understood protective mechanisms. A hormetic model, often used in toxicology to describe a dose-dependent response to a toxic agent, is suggested to study both beneficial and detrimental effects of ischemic postconditioning. Experimental strategies are discussed, including how to define the hazards of ischemic (homologous) postconditioning and the possibility of employing non-ischemic (heterologous) postconditioning to facilitate clinical translation. This review concludes that a more detailed assessment of ischemic postconditioning and studies of a broad range of heterologous postconditioning models are warranted for future clinical translation.
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Affiliation(s)
- Heng Zhao
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305-5327, USA
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Zanuncio JC, Jusselino-Filho P, Ribeiro RC, Castro AA, Zanuncio TV, Serrão JE. Fertility and life expectancy of a predatory stinkbug to sublethal doses of a pyrethroid. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2013; 90:39-45. [PMID: 23132367 DOI: 10.1007/s00128-012-0883-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Accepted: 11/01/2012] [Indexed: 06/01/2023]
Abstract
Podisus distinctus (Heteroptera: Pentatomidae) is an important predator used in biological control of eucalypt defoliating caterpillars, exposed the insecticides. Lower doses of permethrin not affect the values of generation time (T), time necessary to double the population in number of individuals (DT) and intrinsic rate of population increase (r ( m )). Moreover, females of P. distinctus derived from nymphs treated with lower doses of permethrin were more fertile, triggering the effect hormetic in net reproductive rates (Ro). Results showed that low permethrin doses can be used alongside the predatory stinkbug in Integrated Pest Management programs.
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Affiliation(s)
- José C Zanuncio
- Departamento de Biologia Animal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 35670-000, Brazil.
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Abstract
This article offers a broad assessment of the hormetic dose response and its relevance to biomedical researchers, physicians, the pharmaceutical industry, and public health scientists. This article contains a series of 61 questions followed by relatively brief but referenced responses that provides support for the conclusion that hormesis is a reproducible phenomenon, commonly observed, with a frequency far greater than other dose-response models such as the threshold and linear nonthreshold dose-response models. The article provides a detailed background information on the historical foundations of hormesis, its quantitative features, mechanistic foundations, as well as how hormesis is currently being used within medicine and identifying how this concept could be further applied in the development of new therapeutic advances and in improved public health practices.
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Affiliation(s)
- E J Calabrese
- Department of Public Health, Environmental Health Sciences, University of Massachusetts, Amherst, MA 01003, USA.
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48
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An illusion of hormesis in the Ames test: Statistical significance is not equivalent to biological significance. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2012; 746:89-93. [DOI: 10.1016/j.mrgentox.2012.03.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 03/19/2012] [Accepted: 03/21/2012] [Indexed: 11/21/2022]
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49
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Whitelaw S. The emergence of a ‘dose–response’ analogy in the health improvement domain of public health: a critical review. CRITICAL PUBLIC HEALTH 2012. [DOI: 10.1080/09581596.2012.682147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Calabrese EJ, Iavicoli I, Calabrese V. Hormesis: why it is important to biogerontologists. Biogerontology 2012; 13:215-35. [PMID: 22270337 DOI: 10.1007/s10522-012-9374-7] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 01/12/2012] [Indexed: 11/30/2022]
Abstract
This paper offers a broad assessment of the hormetic dose response and its relevance to biogerontology. The paper provides detailed background information on the historical foundations of hormesis, its quantitative features, mechanistic foundations, as well as how the hormesis concept could be further applied in the development of new therapeutic advances in the treatment of age-related diseases. The concept of hormesis has direct application to biogerontology not only affecting the quality of the aging process but also experimental attempts to extend longevity.
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Affiliation(s)
- Edward J Calabrese
- Department of Public Health, Environmental Health Sciences, University of Massachusetts, Amherst, 01003, USA.
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