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Landry T, Huang H. Mini review: The relationship between energy status and adult hippocampal neurogenesis. Neurosci Lett 2021; 765:136261. [PMID: 34562518 DOI: 10.1016/j.neulet.2021.136261] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 08/09/2021] [Accepted: 09/17/2021] [Indexed: 01/10/2023]
Abstract
The ability to generate new hippocampal neurons throughout adulthood and successfully integrate them into existing neural networks is critical to cognitive function, while disordered regulation of this process results in neurodegenerative or psychiatric disease. Consequently, identifying the molecular mechanisms promoting homeostatic hippocampal neurogenesis in adults is essential to understanding the etiologies of these disorders and developing therapeutic interventions. For example, recent evidence identifies a strong association between metabolic function and adult hippocampal neurogenesis. Hippocampal neural stem cell (NSC) fate dynamically fluctuates with changes in substrate availability and energy status (AMP/ATP and NAD+/NADH ratios). Furthermore, many metabolic hormones, such as insulin, insulin-like growth factors, and leptin exhibit dual functions also modulating hippocampal neurogenesis and neuron survivability. These diverse metabolic inputs to NSC's from various tissues seemingly suggest the existence of a system in which energy status can finely modulate hippocampal neurogenesis. Supporting this hypothesis, interventions promoting energy balance, such as caloric restriction, intermittent fasting, and exercise, have shown encouraging potential enhancing hippocampal neurogenesis and cognitive function. Overall, there is a clear relationship between whole body energy status, adult hippocampal neurogenesis, and neuron survival; however, the molecular mechanisms underlying this phenomenon are multifaceted. Thus, the aim of this review is to analyze the literature investigating energy status-mediated regulation of adult neurogenesis in the hippocampus, highlight the neurocircuitry and intracellular signaling involved, and propose impactful future directions in the field.
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Affiliation(s)
- Taylor Landry
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA.
| | - Hu Huang
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, USA; Department of Kinesiology, East Carolina University, Greenville, NC, USA; Human Performance Laboratory, College of Human Performance and Health, East Carolina University, Greenville, NC, USA; Department of Physiology, East Carolina University, Greenville, NC, USA.
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2
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Ton ST, Tsai SY, Vaagenes IC, Glavin K, Wu J, Hsu J, Flink HM, Nockels D, O'Brien TE, Kartje GL. Subventricular zone neural precursor cell responses after traumatic brain injury and binge alcohol in male rats. J Neurosci Res 2019; 97:554-567. [PMID: 30614539 PMCID: PMC6599533 DOI: 10.1002/jnr.24382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 11/10/2022]
Abstract
Traumatic brain injury (TBI) is a major cause of disability worldwide. Additionally, many TBI patients are intoxicated with alcohol at the time of injury, but the impact of acute intoxication on recovery from brain injury is not well understood. We have previously found that binge alcohol prior to TBI impairs spontaneous functional sensorimotor recovery. However, whether alcohol administration in this setting affects reactive neurogenesis after TBI is not known. This study, therefore, sought to determine the short- and long-term effects of pre-TBI binge alcohol on neural precursor cell responses in the subventricular zone (SVZ) following brain injury in male rats. We found that TBI alone significantly increased proliferation in the SVZ as early as 24 hr after injury. Surprisingly, binge alcohol alone also significantly increased proliferation in the SVZ after 24 hr. However, a combined binge alcohol and TBI regimen resulted in decreased TBI-induced proliferation in the SVZ at 24 hr and 1 week post-TBI. Furthermore, at 6 weeks after TBI, binge alcohol administered at the time of TBI significantly decreased the TBI-induced neuroblast response in the SVZ and the rostral migratory stream (RMS). The results from this study suggest that pre-TBI binge alcohol negatively impacts reparative processes in the brain by decreasing short-term neural precursor cell proliferative responses as well as long-term neuroblasts in the SVZ and RMS.
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Affiliation(s)
- Son T Ton
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago Health Sciences Division, Maywood, Illinois
| | - Shih-Yen Tsai
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Ian C Vaagenes
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Kelly Glavin
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Joanna Wu
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Jonathan Hsu
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Hannah M Flink
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Daniel Nockels
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
| | - Timothy E O'Brien
- Department of Mathematics and Statistics, Institute of Environmental Sustainability, Loyola University Chicago, Chicago, Illinois
| | - Gwendolyn L Kartje
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago Health Sciences Division, Maywood, Illinois
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3
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Yang J, Zhang G, Dong D, Shang P. Effects of Iron Overload and Oxidative Damage on the Musculoskeletal System in the Space Environment: Data from Spaceflights and Ground-Based Simulation Models. Int J Mol Sci 2018; 19:E2608. [PMID: 30177626 PMCID: PMC6163331 DOI: 10.3390/ijms19092608] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 08/29/2018] [Accepted: 09/01/2018] [Indexed: 12/15/2022] Open
Abstract
The space environment chiefly includes microgravity and radiation, which seriously threatens the health of astronauts. Bone loss and muscle atrophy are the two most significant changes in mammals after long-term residency in space. In this review, we summarized current understanding of the effects of microgravity and radiation on the musculoskeletal system and discussed the corresponding mechanisms that are related to iron overload and oxidative damage. Furthermore, we enumerated some countermeasures that have a therapeutic potential for bone loss and muscle atrophy through using iron chelators and antioxidants. Future studies for better understanding the mechanism of iron and redox homeostasis imbalance induced by the space environment and developing the countermeasures against iron overload and oxidative damage consequently may facilitate human to travel more safely in space.
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Affiliation(s)
- Jiancheng Yang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Gejing Zhang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Dandan Dong
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, China.
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Peng Shang
- Key Laboratory for Space Bioscience and Biotechnology, Institute of Special Environment Biophysics, Northwestern Polytechnical University, Xi'an 710072, China.
- Research & Development Institute in Shenzhen, Northwestern Polytechnical University, Shenzhen 518057, China.
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Fidaleo M, Cavallucci V, Pani G. Nutrients, neurogenesis and brain ageing: From disease mechanisms to therapeutic opportunities. Biochem Pharmacol 2017; 141:63-76. [PMID: 28539263 DOI: 10.1016/j.bcp.2017.05.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/19/2017] [Indexed: 02/08/2023]
Abstract
Appreciation of the physiological relevance of mammalian adult neurogenesis has in recent years rapidly expanded from a phenomenon of homeostatic cell replacement and brain repair to the current view of a complex process involved in high order cognitive functions. In parallel, an array of endogenous or exogenous triggers of neurogenesis has also been identified, among which metabolic and nutritional cues have drawn significant attention. Converging evidence from animal and in vitro studies points to nutrient sensing and energy metabolism as major physiological determinants of neural stem cell fate, and modulators of the whole neurogenic process. While the cellular and molecular circuitries underlying metabolic regulation of neurogenesis are still incompletely understood, the key role of mitochondrial activity and dynamics, and the importance of autophagy have begun to be fully appreciated; moreover, nutrient-sensitive pathways and transducers such as the insulin-IGF cascade, the AMPK/mTOR axis and the transcription regulators CREB and Sirt-1 have been included, beside more established "developmental" signals like Notch and Wnt, in the molecular networks that dictate neural-stem-cell self-renewal, migration and differentiation in response to local and systemic inputs. Many of these nutrient-related cascades are deregulated in the contest of metabolic diseases and in ageing, and may contribute to impaired neurogenesis and thus to cognition defects observed in these conditions. Importantly, accumulating knowledge on the metabolic control of neurogenesis provides a theoretical framework for the trial of new or repurposed drugs capable of interfering with nutrient sensing as enhancers of neurogenesis in the context of neurodegeneration and brain senescence.
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Affiliation(s)
- Marco Fidaleo
- Institute of General Pathology, Università Cattolica School of Medicine, 00168 Rome, Italy
| | - Virve Cavallucci
- Institute of General Pathology, Università Cattolica School of Medicine, 00168 Rome, Italy
| | - Giovambattista Pani
- Institute of General Pathology, Università Cattolica School of Medicine, 00168 Rome, Italy.
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Pan K, Li X, Chen Y, Zhu D, Li Y, Tao G, Zuo Z. Deferoxamine pre-treatment protects against postoperative cognitive dysfunction of aged rats by depressing microglial activation via ameliorating iron accumulation in hippocampus. Neuropharmacology 2016; 111:180-194. [PMID: 27608977 DOI: 10.1016/j.neuropharm.2016.09.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/08/2016] [Accepted: 09/04/2016] [Indexed: 12/31/2022]
Abstract
Postoperative cognitive dysfunction (POCD) is a common complication of elderly patients after surgery. The mechanisms of POCD have not been clarified. Iron accumulation is a feature of neurodegeneration. Recent reports showed that iron content was increased with impaired cognition induced by surgery. We sought to investigate whether iron chelation would attenuate POCD. In this study, male aged (18 months) Sprague-Dawley rats received 100 mg/kg deferoxamine or saline solution (0.9%) for 6 days before exploratory laparotomy. Cognition was evaluated by Morris water maze before and after surgery. Additional rats received deferoxamine or saline were used to determine hippocampal iron content, iron transport-related proteins (transferrin receptor, divalent metal transporter 1, ferroportin 1 and hepcidin), oxidative stress, microglial activation and brain cell apoptosis. It was found that deferoxamine improved postoperative spatial memory in aged rats. Deferoxamine significantly reduced hippocampal iron concentration and ferritin. Surgery increased divalent metal transporter 1 and hepcidin, decreased transferrin receptor and ferroportin 1, and enhanced ferroportin 1 mRNA. However, deferoxamine reversed the changes of these proteins. Furthermore, deferoxamine sharply reduced the hippocampal reactive oxygen species, malondialdehyde concentration and OX-42 that is a marker of microglia, which might reduce postoperative brain cell apoptosis. This study showed that deferoxamine may improve postoperative cognition of aged rats by ameliorating oxidative stress induced by hippocampal iron accumulation, microglial activation and brain cell apoptosis. This study suggests a potential therapeutic method for reducing POCD.
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Affiliation(s)
- Ke Pan
- Department of Anesthesiology, Southwest Hospital, The Third Military Medical University, Chongqing, China; Department of Anesthesiology, No. 281 Hospital of People's Liberation Army, Hebei, China
| | - Xiaojun Li
- Department of Anesthesiology, Southwest Hospital, The Third Military Medical University, Chongqing, China
| | - Yan Chen
- Department of Anesthesiology, Southwest Hospital, The Third Military Medical University, Chongqing, China
| | - Dan Zhu
- Department of Anesthesiology, Southwest Hospital, The Third Military Medical University, Chongqing, China
| | - Yuping Li
- Department of Anesthesiology, Southwest Hospital, The Third Military Medical University, Chongqing, China
| | - Guocai Tao
- Department of Anesthesiology, Southwest Hospital, The Third Military Medical University, Chongqing, China.
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia, Charlottesville, VA, USA.
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Ke C, Tran K, Chen Y, Di Donato AT, Yu L, Hu Y, Linskey ME, Wang PH, Limoli CL, Zhou YH. Linking differential radiation responses to glioma heterogeneity. Oncotarget 2015; 5:1657-65. [PMID: 24722169 PMCID: PMC4039238 DOI: 10.18632/oncotarget.1823] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The phenotypic and genetic diversity that define tumor subpopulations within high-grade glioma can lead to therapeutic resistance and tumor recurrence. Given that cranial irradiation is a frontline treatment for malignant glioma, understanding how irradiation selectively effects different cellular subpopulations within these heterogeneous cancers should help identify interventions targeted to better combat this deadly disease. To analyze the radiation response of distinct glioma subpopulations, 2 glioma cells lines (U251, A172) were cultured under conditions that promoted either adherence or non-adherent spheroids. Past work has demonstrated that subpopulations derived from defined culture conditions exhibit differences in karyotype, proliferation, gene expression and tumorigenicity. Spheroid cultures from each of the glioma cell lines were found to be more radiosensitive, which was consistent with higher levels of oxidative stress and lower levels of both oxidative phosphorylation and glycolytic metabolism 1 week following irradiation. In contrast, radioresistant non-spheroid parental cultures showed increased glycolytic activity in response to irradiation, while oxidative phosphorylation was affected to a lesser extent. Overall these data suggest that prolonged radiation-induced oxidative stress can compromise the metabolic state of certain glioma subpopulations thereby altering their sensitivity to an important therapeutic intervention used routinely for the control of glioma.
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Affiliation(s)
- Chao Ke
- Neurological Surgery, University of California, Irvine, CA, USA
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Ginsenoside Rg1 prevents cognitive impairment and hippocampus senescence in a rat model of D-galactose-induced aging. PLoS One 2014; 9:e101291. [PMID: 24979747 PMCID: PMC4076296 DOI: 10.1371/journal.pone.0101291] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 06/05/2014] [Indexed: 12/02/2022] Open
Abstract
Neurogenesis continues throughout the lifetime in the hippocampus, while the rate declines with brain aging. It has been hypothesized that reduced neurogenesis may contribute to age-related cognitive impairment. Ginsenoside Rg1 is an active ingredient of Panax ginseng in traditional Chinese medicine, which exerts anti-oxidative and anti-aging effects. This study explores the neuroprotective effect of ginsenoside Rg1 on the hippocampus of the D-gal (D-galactose) induced aging rat model. Sub-acute aging was induced in male SD rats by subcutaneous injection of D-gal (120 mg/kg·d) for 42 days, and the rats were treated with ginsenoside Rg1 (20 mg/kg·d, intraperitoneally) or normal saline for 28 days after 14 days of D-gal injection. In another group, normal male SD rats were treated with ginsenoside Rg1 alone (20 mg/kg·d, intraperitoneally) for 28 days. It showed that administration of ginsenoside Rg1 significantly attenuated all the D-gal-induced changes in the hippocampus, including cognitive capacity, senescence-related markers and hippocampal neurogenesis, compared with the D-gal-treated rats. Further investigation showed that ginsenoside Rg1 protected NSCs/NPCs (neural stem cells/progenitor cells) shown by increased level of SOX-2 expression; reduced astrocytes activation shown by decrease level of Aeg-1 expression; increased the hippocampal cell proliferation; enhanced the activity of the antioxidant enzymes GSH-Px (glutathione peroxidase) and SOD (Superoxide Dismutase); decreased the levels of IL-1β, IL-6 and TNF-α, which are the proinflammatory cytokines; increased the telomere lengths and telomerase activity; and down-regulated the mRNA expression of cellular senescence associated genes p53, p21Cip1/Waf1 and p19Arf in the hippocampus of aged rats. Our data provides evidence that ginsenoside Rg1 can improve cognitive ability, protect NSCs/NPCs and promote neurogenesis by enhancing the antioxidant and anti-inflammatory capacity in the hippocampus.
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Chan M, Chow C, Hamson DK, Lieblich SE, Galea LAM. Effects of chronic oestradiol, progesterone and medroxyprogesterone acetate on hippocampal neurogenesis and adrenal mass in adult female rats. J Neuroendocrinol 2014; 26:386-99. [PMID: 24750490 DOI: 10.1111/jne.12159] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 04/06/2014] [Accepted: 04/12/2014] [Indexed: 12/22/2022]
Abstract
Both natural oestrogens and progesterone influence synaptic plasticity and neurogenesis within the female hippocampus. However, less is known of the impact of synthetic hormones on hippocampal structure and function. There is some evidence that the administration of the synthetic progestin, medroxyprogesterone acetate (MPA) is not as beneficial as natural progesterone and can attenuate oestrogen-induced neuroprotection. Although the effects of oestradiol have been well studied, little is known about the effects of natural and synthetic progestins alone and in combination with oestradiol on adult neurogenesis in females. In the present study, we investigated the effects of chronic oestradiol, progesterone, MPA and the co-administration of each progestin with oestradiol on neurogenesis within the dentate gyrus of adult ovariectomised female rats. Twenty-four hours after a bromodeoxyuridine (BrdU; 200 mg/kg) injection, female rats were repeatedly administered either progesterone (1 or 4 mg), MPA (1 or 4 mg), oestradiol benzoate (EB), progesterone or MPA in combination with EB (10 μg), or vehicle for 21 days. Rats were perfused on day 22 and brain tissue was analysed for the number of BrdU-labelled and Ki67 (an endogenous marker of cell proliferation)-expressing cells. EB alone and MPA + EB significantly decreased neurogenesis and the number of surviving BrdU-labelled cells in the dorsal region of the dentate gyrus, independent of any effects on cell proliferation. Furthermore, MPA (1 and 4 mg) and MPA + EB treated animals had significantly lower adrenal/body mass ratios and reduced serum corticosterone (CORT) levels. By contrast, progesterone + EB treated animals had significantly higher adrenal/body mass ratios and 1 mg of progesterone, progesterone + EB, and EB significantly increased CORT levels. The results of the present study demonstrate that different progestins alone and in combination with oestradiol can differentially affect neurogenesis (via cell survival) and regulation of the hypothalamic-pituitary-adrenal axis. These findings have implications for women using hormone replacement therapies with MPA for both neuroprotection and stress-related disorders.
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Affiliation(s)
- M Chan
- Department of Psychology, Graduate Program in Neuroscience, Brain Research Centre, University of British Columbia, Vancouver, Canada
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Wang J, Deng X, Zhang F, Chen D, Ding W. ZnO nanoparticle-induced oxidative stress triggers apoptosis by activating JNK signaling pathway in cultured primary astrocytes. NANOSCALE RESEARCH LETTERS 2014; 9:117. [PMID: 24624962 PMCID: PMC3995614 DOI: 10.1186/1556-276x-9-117] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 02/20/2014] [Indexed: 05/20/2023]
Abstract
It has been documented in in vitro studies that zinc oxide nanoparticles (ZnO NPs) are capable of inducing oxidative stress, which plays a crucial role in ZnO NP-mediated apoptosis. However, the underlying molecular mechanism of apoptosis in neurocytes induced by ZnO NP exposure was not fully elucidated. In this study, we investigated the potential mechanisms of apoptosis provoked by ZnO NPs in cultured primary astrocytes by exploring the molecular signaling pathways triggered after ZnO NP exposure. ZnO NP exposure was found to reduce cell viability in MTT assays, increase lactate dehydrogenase (LDH) release, stimulate intracellular reactive oxygen species (ROS) generation, and elicit caspase-3 activation in a dose- and time-dependent manner. Apoptosis occurred after ZnO NP exposure as evidenced by nuclear condensation and poly(ADP-ribose) polymerase-1 (PARP) cleavage. A decrease in mitochondrial membrane potential (MMP) with a concomitant increase in the expression of Bax/Bcl-2 ratio suggested that the mitochondria also mediated the pathway involved in ZnO NP-induced apoptosis. In addition, exposure of the cultured cells to ZnO NPs led to phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-related kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK). Moreover, JNK inhibitor (SP600125) significantly reduced ZnO NP-induced cleaved PARP and cleaved caspase-3 expression, but not ERK inhibitor (U0126) or p38 MAPK inhibitor (SB203580), indicating that JNK signaling pathway is involved in ZnO NP-induced apoptosis in primary astrocytes.
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Affiliation(s)
- Jieting Wang
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Xiaobei Deng
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Fang Zhang
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Deliang Chen
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Wenjun Ding
- Laboratory of Environment and Health, College of Life Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
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Nam SM, Choi JH, Yoo DY, Kim W, Jung HY, Kim JW, Kang SY, Park J, Kim DW, Kim WJ, Yoon YS, Hwang IK. Valeriana officinalis extract and its main component, valerenic acid, ameliorate D-galactose-induced reductions in memory, cell proliferation, and neuroblast differentiation by reducing corticosterone levels and lipid peroxidation. Exp Gerontol 2013; 48:1369-77. [PMID: 24055511 DOI: 10.1016/j.exger.2013.09.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 09/09/2013] [Accepted: 09/11/2013] [Indexed: 01/08/2023]
Abstract
Valeriana officinalis is used in herbal medicine of many cultures as mild sedatives and tranquilizers. In this study, we investigated the effects of extract from valerian root extracts and its major component, valerenic acid on memory function, cell proliferation, neuroblast differentiation, serum corticosterone, and lipid peroxidation in adult and aged mice. For the aging model, D-galactose (100 mg/kg) was administered subcutaneously to 6-week-old male mice for 10 weeks. At 13 weeks of age, valerian root extracts (100 mg/kg) or valerenic acid (340 μg/kg) was administered orally to control and D-galactose-treated mice for 3 weeks. The dosage of valerenic acid (340 μg/kg), which is the active ingredient of valerian root extract, was determined by the content of valerenic acid in valerian root extract (3.401±0.066 mg/g) measured by HPLC. The administration of valerian root extract and valerenic acid significantly improved the preferential exploration of new objects in novel object recognition test and the escape latency, swimming speeds, platform crossings, and spatial preference for the target quadrant in Morris water maze test compared to the D-galactose-treated mice. Cell proliferation and neuroblast differentiation were significantly decreased, while serum corticosterone level and lipid peroxidation in hippocampus were significantly increased in the D-galactose-treated group compared to that in the control group. The administration of valerian root extract significantly ameliorated these changes in the dentate gyrus of both control and D-galactose-treated groups. In addition, valerenic acid also mitigated the D-galactose-induced reduction of these changes. These results indicate that valerian root extract and valerenic acid enhance cognitive function, promote cell proliferation and neuroblast differentiation, and reduce serum corticosterone and lipid peroxidation in aged mice.
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Affiliation(s)
- Sung Min Nam
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, South Korea
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Tseng BP, Lan ML, Tran KK, Acharya MM, Giedzinski E, Limoli CL. Characterizing low dose and dose rate effects in rodent and human neural stem cells exposed to proton and gamma irradiation. Redox Biol 2013; 1:153-62. [PMID: 24024148 PMCID: PMC3757683 DOI: 10.1016/j.redox.2013.01.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 01/07/2013] [Accepted: 01/10/2013] [Indexed: 01/25/2023] Open
Abstract
Past work has shown that exposure to gamma rays and protons elicit a persistent oxidative stress in rodent and human neural stem cells (hNSCs). We have now adapted these studies to more realistic exposure scenarios in space, using lower doses and dose rates of these radiation modalities, to further elucidate the role of radiation-induced oxidative stress in these cells. Rodent neural stem and precursor cells grown as neurospheres and human neural stem cells grown as monolayers were subjected to acute and multi-dosing paradigms at differing dose rates and analyzed for changes in reactive oxygen species (ROS), reactive nitrogen species (RNS), nitric oxide and superoxide for 2 days after irradiation. While acute exposures led to significant changes in both cell types, hNSCs in particular, exhibited marked and significant elevations in radiation-induced oxidative stress. Elevated oxidative stress was more significant in hNSCs as opposed to their rodent counterparts, and hNSCs were significantly more sensitive to low dose exposures in terms of survival. Combinations of protons and γ-rays delivered as lower priming or higher challenge doses elicited radioadaptive changes that were associated with improved survival, but in general, only under conditions where the levels of reactive species were suppressed compared to cells irradiated acutely. Protective radioadaptive effects on survival were eliminated in the presence of the antioxidant N-acetylcysteine, suggesting further that radiation-induced oxidative stress could activate pro-survival signaling pathways that were sensitive to redox state. Data corroborates much of our past work and shows that low dose and dose rate exposures elicit significant changes in oxidative stress that have functional consequences on survival.
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Key Words
- CM-H2DCFDA (or CM), 5-(and 6-) Chloromethyl-2,7-dichlorodihydrofluorescein diacetate
- DAF, 4-Amino-5methylamino-2′,7′-difluorescein diacetate
- DNA damage
- Dose rate
- GCR, Galactic cosmic rays
- HDR, High dose rate
- LDR, Low dose rate
- LET, Linear energy transfer
- MS, Mitosox
- NAC, N-acetylcysteine
- Neural stem cells
- Oxidative stress
- Protons
- RNS, Reactive nitrogen species
- ROS, Reactive oxygen species
- Radiation
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Affiliation(s)
- Bertrand P. Tseng
- Department of Internal Medicine, Duke University Medical Center, Durham, NC 27710, United States
| | - Mary L. Lan
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, United States
| | - Katherine K. Tran
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, United States
| | - Munjal M. Acharya
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, United States
| | - Erich Giedzinski
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, United States
| | - Charles L. Limoli
- Department of Radiation Oncology, University of California, Irvine, CA 92697-2695, United States
- Correspondence to: Department of Radiation Oncology University of California Irvine, Medical Sciences I, Room B-146B Irvine CA 92697-2695, USA. Tel.: +1 949 824 3053; fax: +1 949 824 3566.
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Rana P, Khan AR, Modi S, Hemanth Kumar BS, Javed S, Tripathi RP, Khushu S. Altered brain metabolism after whole body irradiation in mice: a preliminary in vivo 1H MRS study. Int J Radiat Biol 2012; 89:212-8. [PMID: 23020784 DOI: 10.3109/09553002.2013.734944] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
UNLABELLED Abstract Purpose: In the classical description of acute radiation syndrome, the role of central nervous system (CNS) is underestimated. It is now well recognised that ionising radiation-induced oxidative stress may bring about functional changes in the brain. In this study, we prospectively evaluated metabolic changes in the brain after whole body irradiation in mice using in vivo proton ((1)H) nuclear magnetic resonance spectroscopy (MRS). MATERIAL AND METHODS Young adult mice were exposed to whole body irradiation of 8 Gy and controls were sham irradiated. In vivo (1)H MRS from cortex-hippocampus and hypothalamic-thalamic region of brain at different time points, i.e., as early as 6 hours, day 1, 2, 3, 5 and 10 post irradiation was carried out at 7 Tesla animal magnetic resonance imaging system. Brain metabolites were measured and quantitative analysis of detectable metabolites was performed by linear combination of model (LCModel). RESULTS Significant reduction in myoinositol (p = 0.03) and taurine (p = 0.02) ratios were observed in cortex-hippocampus region as early as day 2 post irradiation compared to controls. These metabolic alterations remained sustained over day 10 post irradiation. CONCLUSIONS The results of this preliminary study suggest that the alteration/reduction in the mI and Tau concentration may be associated with physiological perturbations in astrocytes or radiation induced neuro-inflammatory response triggered in microglial cell.
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Affiliation(s)
- Poonam Rana
- NMR Research Centre, Institute of Nuclear Medicine and Allied Sciences (INMAS), Delhi
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13
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Cheng X, Wang G, Ma ZL, Chen YY, Fan JJ, Zhang ZL, Lee KKH, Luo HM, Yang X. Exposure to 2,5-hexanedione can induce neural malformations in chick embryos. Neurotoxicology 2012; 33:1239-47. [DOI: 10.1016/j.neuro.2012.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 06/18/2012] [Accepted: 07/17/2012] [Indexed: 11/26/2022]
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14
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Stessin AM, Gursel DB, Schwartz A, Parashar B, Kulidzhanov FG, Sabbas AM, Boockvar J, Nori D, Wernicke AG. FTY720, sphingosine 1-phosphate receptor modulator, selectively radioprotects hippocampal neural stem cells. Neurosci Lett 2012; 516:253-8. [PMID: 22507238 DOI: 10.1016/j.neulet.2012.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 03/30/2012] [Accepted: 04/01/2012] [Indexed: 12/27/2022]
Abstract
Cranial irradiation is an effective treatment modality for both primary and metastatic brain tumors, yet it induces cognitive decline in a substantial number of patients. At present, there are no established methods for neuroprotection. Recent investigations have revealed a link between radiation-induced cognitive dysfunction and the loss of neural precursor cells in the hippocampus. Hence, identifying pharmacological agents, capable of protecting this cell population, is of interest. FTY720 (fingolimod), an FDA-approved oral drug for the treatment of multiple sclerosis, has been shown to promote the survival and differentiation of neural progenitors, as well as remyelination and repair after brain injury. In this study, we show that FTY720, used at nanomolar concentrations, is capable of increasing the viability and neurogenicity of irradiated neural stem cells from the hippocampus. In contrast, it does not provide radioprotection in a human breast cancer cell line and two glioma cell lines. These results suggest a potential therapeutic role for FTY720 as a neuroprotector during cranial irradiation. Further preclinical studies are warranted to evaluate this possibility.
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Affiliation(s)
- Alexander M Stessin
- Department of Radiation Oncology, Weill Medical College of Cornell University, New York, NY 10065, USA.
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15
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Yoo DY, Kim W, Lee CH, Shin BN, Nam SM, Choi JH, Won MH, Yoon YS, Hwang IK. Melatonin improves D-galactose-induced aging effects on behavior, neurogenesis, and lipid peroxidation in the mouse dentate gyrus via increasing pCREB expression. J Pineal Res 2012; 52:21-8. [PMID: 21718363 DOI: 10.1111/j.1600-079x.2011.00912.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Melatonin (N-acetyl-5-methoxytryptamine) has multiple functions. In this study, we investigated the effects of melatonin on memory, cell proliferation, and neuroblast differentiation in the dentate gyrus of a mouse model of D-galactose-induced aging. D-galactose was subcutaneously administered to 7-wk-old mice for 10 wk, and age-matched mice were used as controls. Seven weeks after D-galactose administration, vehicle (water) or melatonin (6 mg/L in water) was administered ad libitum to the mice for 3 wk. The administration of D-galactose significantly increased the escape latency compared with that in the control mice on days 1-3. In addition, cells in the subgranular zone and in the granule cell layer of the dentate gyrus showed severe damage (cytoplasmic condensation) in the D-galactose-treated mice. However, melatonin supplementation to these mice for 3 wk significantly ameliorated the D-galactose-induced increase in escape latency and neuronal damage compared with the vehicle-treated group. The administration of melatonin also significantly restored the D-galactose-induced reduction of proliferating cells (Ki67-positive cells) and differentiating neuroblasts (doublecortin-positive neuroblasts) in the dentate gyrus. Furthermore, the administration of melatonin significantly increased Ser133-phosphorylated cyclic AMP response element binding protein in the dentate gyrus. The administration of melatonin significantly reduced D-galactose-induced lipid peroxidation in the dentate gyrus. These results suggest that melatonin may be helpful in reducing age-related phenomena in the brain.
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Affiliation(s)
- Dae Young Yoo
- Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
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16
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KRASIEVA TATIANAB, GIEDZINSKI ERICH, TRAN KATHERINE, LAN MARY, LIMOLI CHARLESL, TROMBERG BRUCEJ. PROBING THE IMPACT OF GAMMA-IRRADIATION ON THE METABOLIC STATE OF NEURAL STEM AND PRECURSOR CELLS USING DUAL-WAVELENGTH INTRINSIC SIGNAL TWO-PHOTON EXCITED FLUORESCENCE. JOURNAL OF INNOVATIVE OPTICAL HEALTH SCIENCES 2011; 4:289-300. [PMID: 23869199 PMCID: PMC3712535 DOI: 10.1142/s1793545811001629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Two-photon excited fluorescence (TPEF) spectroscopy and imaging were used to investigate the effects of gamma-irradiation on neural stem and precursor cells (NSPCs). While the observed signal from reduced nicotinamide adenine dinucleotide (NADH) was localized to the mitochondria, the signal typically associated with oxidized flavoproteins (Fp) was distributed diffusely throughout the cell. The measured TPEF emission and excitation spectra were similar to the established spectra of NAD(P)H and Fp. Fp fluorescence intensity was markedly increased by addition of the electron transport chain (ETC) modulator menadione to the medium, along with a concomitant decrease in the NAD(P)H signal. Three-dimensional (3D) neurospheres were imaged to obtain the cellular metabolic index (CMI), calculated as the ratio of Fp to NAD(P)H fluorescence intensity. Radiation effects were found to differ between low-dose (≤ 50 cGy) and high-dose (≥ 50 cGy) exposures. Low-dose irradiation caused a marked drop in CMI values accompanied by increased cellular proliferation. At higher doses, both NAD(P)H and Fp signals increased, leading to an overall elevation in CMI values. These findings underscore the complex relationship between radiation dose, metabolic state, and proliferation status in NSPCs and highlight the ability of TPEF spectroscopy and imaging to characterize metabolism in 3D spheroids.
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Affiliation(s)
- TATIANA B. KRASIEVA
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
| | - ERICH GIEDZINSKI
- Department of Radiation Oncology, University of California, Irvine, California 92697, USA
| | - KATHERINE TRAN
- Department of Radiation Oncology, University of California, Irvine, California 92697, USA
| | - MARY LAN
- Department of Radiation Oncology, University of California, Irvine, California 92697, USA
| | - CHARLES L. LIMOLI
- Department of Radiation Oncology, University of California, Irvine, California 92697, USA
| | - BRUCE J. TROMBERG
- Laser Microbeam and Medical Program, Beckman Laser Institute, University of California, Irvine, 1002 Health Sciences Road East, Irvine, CA 92612, USA
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Siebzehnrubl FA, Reynolds BA, Vescovi A, Steindler DA, Deleyrolle LP. The origins of glioma: E Pluribus Unum? Glia 2011; 59:1135-47. [DOI: 10.1002/glia.21143] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Accepted: 12/17/2010] [Indexed: 01/19/2023]
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18
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Mao XW, Favre CJ, Fike JR, Kubinova L, Anderson E, Campbell-Beachler M, Jones T, Smith A, Rightnar S, Nelson GA. High-LET radiation-induced response of microvessels in the Hippocampus. Radiat Res 2010; 173:486-93. [PMID: 20334521 DOI: 10.1667/rr1728.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The hippocampus is critical for learning and memory, and injury to this structure is associated with cognitive deficits. The response of the hippocampal microvessels after a relatively low dose of high-LET radiation remains unclear. In this study, endothelial population changes in hippocampal microvessels exposed to (56)Fe ions at doses of 0, 0.5, 2 and 4 Gy were quantified using unbiased stereological techniques. Twelve months after exposure, mice that received 0.5 Gy or 2 Gy of iron ions showed a 34% or 29% loss of endothelial cells, respectively, in the hippocampal cornu ammonis region 1 (CA1) compared to age-matched controls or mice that received 4 Gy (P < 0.05). We suggest that this "U-shaped" dose response indicates a repopulation from a sensitive subset of endothelial cells that occurred after 4 Gy that was stimulated by an initial rapid loss of endothelial cells. In contrast to the CA1, in the dentate gyrus (DG), there was no significant difference in microvessel cell and length density between irradiated groups and age-matched controls. Vascular topology differences between CA1 and DG may account for the variation in dose response. The correlation between radiation-induced alterations in the hippocampal microvessels and their functional consequences must be investigated in further studies.
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Affiliation(s)
- Xiao Wen Mao
- Departments of Radiation Medicine, Molecular Radiation Biology Laboratories, Loma Linda University, Loma Linda, California 92350, USA.
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19
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Kim J, Wong PKY. Loss of ATM impairs proliferation of neural stem cells through oxidative stress-mediated p38 MAPK signaling. Stem Cells 2010; 27:1987-98. [PMID: 19544430 DOI: 10.1002/stem.125] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ataxia-telangiectasia (A-T) is a genetic disorder caused by a mutation of the Atm gene, which controls DNA repair, cell cycling, and redox homeostasis. Even though oxidative stress has been implicated in the neurological anomalies in A-T, the effects of ATM loss on neural stem cell (NSC) survival has remained elusive. In this study, we investigated the effects of oxidative stress on NSC proliferation in an animal model for A-T neurodegeneration. We found that cultured subventricular zone neurosphere cells from Atm(-/-) mice show impaired proliferation, as well as intrinsic elevation of reactive oxygen species (ROS) levels, compared with those from Atm(+/+) mice. We also show that increasing the levels of ROS by H(2)O(2) treatment significantly reduces Atm(+/+) neurosphere formation and proliferation. In Atm(-/-) neurosphere cells, the Akt and Erk1/2 pathways are disrupted, together with enhanced activity of the p38 mitogen-activated protein kinase (MAPK). Treatment of these cells with the antioxidant N-acetyl-L-cysteine (NAC) or with a p38 MAPK inhibitor restores normal proliferation and reduced expression of p21(cip1) and p27(kip1) in the Atm(-/-) NSCs. These observations indicate that ATM plays a crucial role in NSC proliferation, by activating Akt and Erk1/2 pathways and by suppressing ROS-p38 MAPK signaling. Together, our results suggest that p38 MAPK signaling acts as a negative regulator of NSC proliferation in response to oxidative stress. These findings suggest a potential mechanism for neuronal cell loss as a result of oxidative stress in NSCs in progressive neurodegenerative diseases such as A-T.
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Affiliation(s)
- Jeesun Kim
- Department of Carcinogenesis, University of Texas M.D. Anderson Cancer Center, Smithville, Texas 78957, USA
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20
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Basina BR, Olson C, Roy DK, Yen CP, Schlesinger D, Nagayama K, Sheehan JP. Radiation dose and incidence of new metastasis in the anterior temporal lobe structures of radiosurgically treated patients. J Neurosurg 2010; 112:122-9. [DOI: 10.3171/2009.4.jns09249] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Gamma Knife surgery (GKS) is frequently used to treat patients with metastasis to the brain. Radiosurgery seeks to limit radiation to the brain tissue surrounding the metastatic deposits. In patients with such lesions, a low radiation dose to the eloquent brain may help to prevent adverse effects. In this study the authors aimed to quantify the radiosurgical dose delivered to the anterior temporal structures in cases of metastatic brain lesions. They also evaluated the incidence and timing of new metastases in the anterior temporal lobes (ATLs) in patient cohorts that underwent GKS with or without whole-brain radiation therapy (WBRT).
Methods
The authors retrospectively analyzed 100 patients with metastatic brain lesions treated with GKS at the University of Virginia Health System. The anterior 5 cm of the temporal lobes and the hippocampi within the ATLs were contoured on the Gamma Knife planning station. Using the dose-volume histogram function in GammaPlan, treatment parameters for the metastases as well as radiation doses to the contoured ATLs and hippocampi were measured. Patients had clinical and MR imaging follow-ups at 3-month intervals. The ATLs and hippocampal regions were evaluated for the formation of new metastases on follow-up imaging.
Results
The demographic data—age, sex, Karnofsky Performance Scale score, number of temporal metastases at the time of GKS, total volume of metastatic tumors per patient, and number of intracranial metastatic deposits—were similar in the 2 cohorts. In patients without an ATL metastasis at the time of GKS, the mean maximum, 50% volume, and integral doses of radiation to the anterior temporal structures were very low: 2.6 Gy, 0.6 Gy, and 36.3 mJ in the GKS cohort and 2.1 Gy, 0.6 Gy, and 40.9 mJ in the GKS+WBRT cohort, respectively. Among the ATLs that had not shown a brain metastasis at the time of GKS, 8 of 92 temporal lobes in the GKS cohort and 10 of 89 in the GKS+WBRT cohort demonstrated a new anterior temporal lesion on follow-up MR imaging.
Conclusions
Gamma Knife surgery delivered a low dose of background radiation to the ATLs and hippocampi. The incidence of a new ATL metastasis in the GKS cohort was not higher than in the GKS+WBRT cohort. Gamma Knife surgery in the management of brain metastases limits the delivery of radiation to eloquent brain tissue without evidence of an appreciable propensity to develop new metastatic disease in the ATLs or hippocampi. This therapeutic approach may help to avoid unintended neurological dysfunction due to nonspecific delivery of radiation to eloquent brain tissues.
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21
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Ramanan S, Zhao W, Riddle DR, Robbins ME. Role of PPARs in Radiation-Induced Brain Injury. PPAR Res 2009; 2010:234975. [PMID: 19789638 PMCID: PMC2748193 DOI: 10.1155/2010/234975] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Accepted: 07/15/2009] [Indexed: 11/17/2022] Open
Abstract
Whole-brain irradiation (WBI) represents the primary mode of treatment for brain metastases; about 200 000 patients receive WBI each year in the USA. Up to 50% of adult and 100% of pediatric brain cancer patients who survive >6 months post-WBI will suffer from a progressive, cognitive impairment. At present, there are no proven long-term treatments or preventive strategies for this significant radiation-induced late effect. Recent studies suggest that the pathogenesis of radiation-induced brain injury involves WBI-mediated increases in oxidative stress and/or inflammatory responses in the brain. Therefore, anti-inflammatory strategies can be employed to modulate radiation-induced brain injury. Peroxisomal proliferator-activated receptors (PPARs) are ligand-activated transcription factors that belong to the steroid/thyroid hormone nuclear receptor superfamily. Although traditionally known to play a role in metabolism, increasing evidence suggests a role for PPARs in regulating the response to inflammation and oxidative injury. PPAR agonists have been shown to cross the blood-brain barrier and confer neuroprotection in animal models of CNS disorders such as stroke, multiple sclerosis and Parkinson's disease. However, the role of PPARs in radiation-induced brain injury is unclear. In this manuscript, we review the current knowledge and the emerging insights about the role of PPARs in modulating radiation-induced brain injury.
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Affiliation(s)
- Sriram Ramanan
- Department of Cancer Biology, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
- Brain Tumor Center of Excellence, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Weiling Zhao
- Brain Tumor Center of Excellence, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
- Department of Radiation Oncology, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - David R. Riddle
- Brain Tumor Center of Excellence, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
- Department of Neurobiology and Anatomy, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Mike E. Robbins
- Brain Tumor Center of Excellence, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
- Department of Radiation Oncology, Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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22
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Fike JR, Rosi S, Limoli CL. Neural precursor cells and central nervous system radiation sensitivity. Semin Radiat Oncol 2009; 19:122-32. [PMID: 19249650 DOI: 10.1016/j.semradonc.2008.12.003] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The tolerance of normal brain tissues limits the radiation dose that can be delivered safely during cranial radiotherapy, and one of the potential complications that can arise involves cognitive impairment. Extensive laboratory data have appeared recently showing that hippocampal neurogenesis is significantly impacted by irradiation and that such changes are associated with altered cognitive function and involve, in part, changes in the microenvironment (oxidative stress and inflammation). Although there is considerable uncertainty about exactly how these changes evolve, new in vitro and in vivo approaches have provided a means by which new mechanistic insights can be gained relevant to the topic. Together, the data from cell culture and animal-based studies provide complementary information relevant to a potentially serious complication of cranial radiotherapy and should enhance our understanding of the tolerance of normal brain after cranial irradiation.
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Affiliation(s)
- John R Fike
- Brain and Spinal Injury Center, University of California, San Francisco, CA 94110-0899, USA.
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23
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Kim MS, Park HR, Park M, Kim SJ, Kwon M, Yu BP, Chung HY, Kim HS, Kwack SJ, Kang TS, Kim SH, Lee J. Neurotoxic effect of 2,5-hexanedione on neural progenitor cells and hippocampal neurogenesis. Toxicology 2009; 260:97-103. [PMID: 19464574 DOI: 10.1016/j.tox.2009.03.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Revised: 03/16/2009] [Accepted: 03/16/2009] [Indexed: 01/14/2023]
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Cortes-Wanstreet MM, Giedzinski E, Limoli CL, Luderer U. Overexpression of glutamate-cysteine ligase protects human COV434 granulosa tumour cells against oxidative and gamma-radiation-induced cell death. Mutagenesis 2009; 24:211-24. [PMID: 19153097 DOI: 10.1093/mutage/gen073] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Ionizing radiation is toxic to ovarian follicles and can cause infertility. Generation of reactive oxygen species (ROS) has been implicated in the toxicity of ionizing radiation in several cell types. We have shown that depletion of the antioxidant glutathione (GSH) sensitizes follicles and granulosa cells to toxicant-induced apoptosis and that supplementation of GSH is protective. The rate-limiting reaction in GSH biosynthesis is catalysed by glutamate-cysteine ligase (GCL), which consists of a catalytic subunit (GCLC) and a regulatory subunit (GCLM). We hypothesized that overexpression of Gclc or Gclm to increase GSH synthesis would protect granulosa cells against oxidant- and radiation-induced cell death. The COV434 line of human granulosa tumour cells was stably transfected with vectors designed for the constitutive expression of Gclc, Gclm, both Gclc and Gclm or empty vector. GCL protein and enzymatic activity and total GSH levels were significantly increased in the GCL subunit-transfected cells. GCL-transfected cells were resistant to cell killing by treatment with hydrogen peroxide compared to control cells. Cell viability declined less in all the GCL subunit-transfected cell lines 1-8 h after 0.5 mM hydrogen peroxide treatment than in control cells. We next examined the effects of GCL overexpression on responses to ionizing radiation. ROS were measured using a redox-sensitive fluorogenic dye in cells irradiated with 0, 1 or 5 Gy of gamma-rays. There was a dose-dependent increase in ROS within 30 min in all cell lines, an effect that was significantly attenuated in Gcl-transfected cells. Apoptosis, assessed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labelling and activated caspase-3 immunoblotting, was significantly decreased in irradiated Gclc-transfected cells compared to irradiated control cells. Suppression of GSH synthesis in Gclc-transfected cells reversed resistance to radiation. These findings show that overexpression of GCL in granulosa cells can augment GSH synthesis and ameliorate various sequelae associated with exposure to oxidative stress and irradiation.
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Affiliation(s)
- Mabel M Cortes-Wanstreet
- Department of Developmental and Cell Biology, University of California Irvine, Irvine, CA 92617, USA
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Elevated DNA damage in a mouse model of oxidative stress: impacts of ionizing radiation and a protective dietary supplement. Mutagenesis 2008; 23:473-82. [DOI: 10.1093/mutage/gen036] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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26
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Calingasan NY, Ho DJ, Wille EJ, Campagna MV, Ruan J, Dumont M, Yang L, Shi Q, Gibson GE, Beal MF. Influence of mitochondrial enzyme deficiency on adult neurogenesis in mouse models of neurodegenerative diseases. Neuroscience 2008; 153:986-96. [PMID: 18423880 DOI: 10.1016/j.neuroscience.2008.02.071] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Revised: 02/03/2008] [Accepted: 02/27/2008] [Indexed: 02/04/2023]
Abstract
Mitochondrial defects including reduction of a key mitochondrial tricarboxylic acid cycle enzyme alpha-ketoglutarate-dehydrogenase complex (KGDHC) are characteristic of many neurodegenerative diseases. KGDHC consists of alpha-ketoglutarate dehydrogenase, dihydrolipoyl succinyltransferase (E2k), and dihydrolipoamide dehydrogenase (Dld) subunits. We investigated whether Dld or E2k deficiency influences adult brain neurogenesis using immunohistochemistry for the immature neuron markers, doublecortin (Dcx) and polysialic acid-neural cell adhesion molecule, as well as a marker for proliferation, proliferating cell nuclear antigen (PCNA). Both Dld- and E2k-deficient mice showed reduced Dcx-positive neuroblasts in the subgranular zone (SGZ) of the hippocampal dentate gyrus compared with wild-type mice. In the E2k knockout mice, increased immunoreactivity for the lipid peroxidation marker, malondialdehyde occurred in the SGZ. These alterations did not occur in the subventricular zone (SVZ). PCNA staining revealed decreased proliferation in the SGZ of E2k-deficient mice. In a transgenic mouse model of Alzheimer's disease, Dcx-positive cells in the SGZ were also reduced compared with wild type, but Dld deficiency did not exacerbate the reduction. In the malonate lesion model of Huntington's disease, Dld deficiency did not alter the lesion-induced increase and migration of Dcx-positive cells from the SVZ into the ipsilateral striatum. Thus, the KGDHC subunit deficiencies associated with elevated lipid peroxidation selectively reduced the number of neuroblasts and proliferating cells in the hippocampal neurogenic zone. However, these mitochondrial defects neither exacerbated certain pathological conditions, such as amyloid precursor protein (APP) mutation-induced reduction of SGZ neuroblasts, nor inhibited malonate-induced migration of SVZ neuroblasts. Our findings support the view that mitochondrial dysfunction can influence the number of neural progenitor cells in the hippocampus of adult mice.
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Affiliation(s)
- N Y Calingasan
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY 10065, USA.
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Elmore E, Lao XY, Kapadia R, Giedzinski E, Limoli C, Redpath JL. Low Doses of Very Low-Dose-Rate Low-LET Radiation Suppress Radiation-Induced Neoplastic TransformationIn Vitroand Induce an Adaptive Response. Radiat Res 2008; 169:311-8. [DOI: 10.1667/rr1199.1] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Accepted: 11/15/2007] [Indexed: 11/03/2022]
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28
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Limoli CL, Giedzinski E, Baure J, Rola R, Fike JR. Redox changes induced in hippocampal precursor cells by heavy ion irradiation. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2007; 46:167-72. [PMID: 17103219 DOI: 10.1007/s00411-006-0077-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 10/23/2006] [Indexed: 05/12/2023]
Abstract
Hippocampal precursors retain the capacity to proliferate and differentiate throughout life, and their progeny, immature neurons, can undergo neurogenesis, a process believed to be important in maintaining the cognitive health of an organism. A variety of stresses including irradiation have been shown to deplete neural precursor cells, an effect that inhibits neurogenesis and is associated with the onset of cognitive impairments. Our past work has shown that neural precursor cells exposed to X-rays or protons exhibit a prolonged increase in oxidative stress, a factor we hypothesize to be critical in regulating the function of these cells after irradiation and other stresses. Here we report that irradiation of hippocampal precursor cells with high-linear energy transfer (LET) 1 GeV/nucleon 56Fe ions leads to significantly higher levels of oxidative stress when compared to lower LET radiations (X-rays, protons). Irradiation with 1 Gy of 56Fe ions elicits twofold to fivefold higher levels of reactive oxygen species (ROS) compared to unirradiated controls, and at lower doses (<or=1 Gy) neural precursors exhibit a linear dose response 6 h after heavy ion exposure. The use of the antioxidant lipoic acid (LA) was able to reduce ROS levels below background levels when added before or after 56Fe ion irradiation. These results conclusively show that low doses of 56Fe ions can elicit significant levels of oxidative stress in neural precursor cells. Given the prevalence of heavy ions in space and the duration of interplanetary travel, these data suggest that astronauts are at risk for developing cognitive decrements. However, our results also indicate that antioxidants delivered before as radioprotective agents or after as mitigating agents hold promise as effective countermeasures for ameliorating certain adverse effects of heavy ion exposure to the CNS.
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Affiliation(s)
- C L Limoli
- Department of Radiation Oncology, University of California Irvine, Medical Sciences I, Room B-149, Irvine, CA 92697-2695, USA.
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