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Wang J, Wu C, Zhang X, Song Y, Wang B, Zhang K, Sun M. Developmental neurotoxic effects of bisphenol A and its derivatives in Drosophila melanogaster. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 260:115098. [PMID: 37269611 DOI: 10.1016/j.ecoenv.2023.115098] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/19/2023] [Accepted: 05/31/2023] [Indexed: 06/05/2023]
Abstract
As a result of the ban on bisphenol A (BPA), a hormone disruptor with developmental neurotoxicity, several BPA derivatives (BPs) have been widely used in industrial production. However, there are no effective methods for assessing the neurodevelopmental toxic effects of BPs. To address this, a Drosophila exposure model was established, and W1118 was reared in food containing these BPs. Results showed that each BPs displayed different semi-lethal doses ranging from 1.76 to 19.43 mM. Exposure to BPs delayed larval development and affected axonal growth, resulting in the abnormal crossing of the midline of axons in the β lobules of mushroom bodies, but the damage caused by BPE and BPF was relatively minor. BPC, BPAF, and BPAP have the most significant effects on locomotor behavior, whereas BPC exhibited the most affected social interactions. Furthermore, exposure to high-dose BPA, BPC, BPS, BPAF, and BPAP also significantly increased the expression of Drosophila estrogen-related receptors. These demonstrated that different kinds of BPs had different levels of neurodevelopmental toxicity, and the severity was BPZ > BPC and BPAF > BPB > BPS > BPAP ≈ BPAl ≈ BPF > BPE. Therefore, BPZ, BPC, BPS, BPAF, and BPAP should be evaluated as potential alternatives to BPA.
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Affiliation(s)
- Jie Wang
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Chunyan Wu
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Xing Zhang
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Yuanyuan Song
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Binquan Wang
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Ke Zhang
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China
| | - Mingkuan Sun
- The Key Laboratory of Modern Toxicology, Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
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2
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Xue R, Yang K, Xiao F, Yang L, Chen G, Li Y, Ye Y, Chen K, Smith ST, Li G, Kong Q, Zhou J. dNAGLU Extends Life Span and Promotes Fitness and Stress Resistance in Drosophila. Int J Mol Sci 2022; 23:ijms232214433. [PMID: 36430913 PMCID: PMC9694703 DOI: 10.3390/ijms232214433] [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: 10/10/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022] Open
Abstract
To identify new factors that promote longevity and healthy aging, we studied Drosophila CG13397, an ortholog of the human NAGLU gene, a lysosomal enzyme overexpressed in centenarians. We found that the overexpression of CG13397 (dNAGLU) ubiquitously, or tissue specifically, in the nervous system or fat body could extend fly life span. It also extended the life span of flies overexpressing human Aβ42, in a Drosophila Alzheimer's disease (AD) model. To investigate whether dNAGLU could influence health span, we analyzed the effect of its overexpression on AD flies and found that it improved the climbing ability and stress resistance, including desiccation and hunger, suggesting that dNAGLU improved fly health span. We found that the deposition of Aβ42 in the mushroom body, which is the fly central nervous system, was reduced, and the lysosomal activity in the intestine was increased in dNAGLU over-expressing flies. When NAGLU was overexpressed in human U251-APP cells, which expresses a mutant form of the Aβ-precursor protein (APP), APP-p.M671L, these cells exhibited stronger lysosomal activity and and enhanced expression of lysosomal pathway genes. The concentration of Aβ42 in the cell supernatant was reduced, and the growth arrest caused by APP expression was reversed, suggesting that NAGLU could play a wider role beyond its catalytic activity to enhance lysosomal activity. These results also suggest that NAGLU overexpression could be explored to promote healthy aging and to prevent the onset of neurodegenerative diseases, including AD.
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Affiliation(s)
- Rubing Xue
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ke Yang
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fuhui Xiao
- State Key Laboratory of Genetic Resources and Evolution/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650201, China
| | - Liping Yang
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
| | - Guijun Chen
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
| | - Yongxuan Li
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunshuang Ye
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
| | - Kangning Chen
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sheryl T. Smith
- Biology Department, Arcadia University, Glenside, PA 19038, USA
| | - Gonghua Li
- State Key Laboratory of Genetic Resources and Evolution/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650201, China
- KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming 650223, China
| | - Qingpeng Kong
- State Key Laboratory of Genetic Resources and Evolution/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650201, China
- KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming 650223, China
| | - Jumin Zhou
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences/Key Laboratory of Healthy Aging Research of Yunnan Province, Kunming Key Laboratory of Healthy Aging Study, Kunming Institute of Zoology, Kunming 650223, China
- KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming 650223, China
- Correspondence:
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3
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Nikookar H, Haddadi M, Haghi M, Masoudi R. DNT1 Downregulation and Increased Ethanol Sensitivity in Transgenic Drosophila Models of Alzheimer's Disease. Arch Gerontol Geriatr 2021; 94:104355. [PMID: 33550108 DOI: 10.1016/j.archger.2021.104355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/30/2020] [Accepted: 01/21/2021] [Indexed: 11/19/2022]
Abstract
Two major pathological hallmarks of Alzheimer's disease (AD) are amyloid plaques and neurofibrillary tangles of hyperphosphorylated tau. Aggregation of amyloid-β (Aβ) is considered as the primary insult in AD. However, failure in treatments based on targetingAβ without considering the pathologic tau and close correlation between pathological tau and cognitive decline highlighted the crucial role of tau in AD. Loss of synaptic plasticity and cognitive decline, partly due to decrease in Brain Derived Neurotrophic Factor (BDNF), are other hallmarks of AD. Aβ and tau downregulate BDNF at both transcriptional and translational levels. The aim of this research was to study the expression levels of Drosophila Neuroteophin 1 (DNT1), as an orthologue of BDNF, in flies expressing Aβ42 or tauR406W. Levels of DNT1 were determined using quantitative real time PCR. Behavioral and Biochemical investigations were also performed in parallel. Our results showed that there is a significant decrease in the levels of DNT1 expression in Aβ42 or tauR406W expressing flies. Interestingly, a significant increase was observed in sensitivity to ethanol in both transgenic flies. Rise in Reactive Oxygen Species (ROS) levels was also detected. We concluded that both Aβ and pathological tau exert their toxic effect on DNT1 expression, ROS production, and response to ethanol, independently. Interestingly, pathological tau showed higher impact on the ROS production compared to Aβ. It seems that Aβ42 and tauR406W transgenic flies are proper models to investigate the interplay between BDNF and oxidative stress, and also to assess the mechanism underlying behavioral response to ethanol.
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Affiliation(s)
- Hoda Nikookar
- Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
| | - Mohammad Haddadi
- Department of Biology, Faculty of Basic Sciences, University of Zabol, Zabol, Iran
| | - Mehrnaz Haghi
- Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
| | - Raheleh Masoudi
- Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran.
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4
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Cordone S, Annarumma L, Rossini PM, De Gennaro L. Sleep and β-Amyloid Deposition in Alzheimer Disease: Insights on Mechanisms and Possible Innovative Treatments. Front Pharmacol 2019; 10:695. [PMID: 31281257 PMCID: PMC6595048 DOI: 10.3389/fphar.2019.00695] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 05/28/2019] [Indexed: 02/05/2023] Open
Abstract
The growing interest in the preclinical stage of Alzheimer's disease (AD) led investigators to identify modifiable risk and predictive factors useful to design early intervention strategies. The preclinical stage of AD is characterized by β-amyloid (Aβ) aggregation into amyloid plaques and tau phosphorylation and aggregation into neurofibrillary tangles. There is a consensus on the importance of sleep within this context: the bidirectional relationship between sleep and AD pathology is supported by growing evidence that proved that the occurrence of sleep changes starting from the preclinical stage of AD, many years before the onset of cognitive decline. Hence, we review the most recent studies on sleep disturbances related to Aβ and the effects of sleep deprivation on Aβ accumulation in animal and human models. We also discuss evidence on the role of sleep in clearing the brain of toxic metabolic by-products, with original findings of the clearance activity of the glymphatic system stimulated by sleep. Furthermore, starting from new recent advances about the relationship between slow-wave sleep (SWS) and Aβ burden, we review the results of recent electroencephalographic (EEG) studies in order to clarify the possible role of SWS component disruption as a novel mechanistic pathway through which Aβ pathology may contribute to cognitive decline and, conversely, the eventual useful role of SWS in facilitating Aβ clearance. Finally, we discuss some promising innovative, effective, low-risk, non-invasive interventions, although empirical evidence on the efficacy of sleep interventions in improving the course of AD is at the very beginning.
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Affiliation(s)
- Susanna Cordone
- Department of Psychology, University of Rome "Sapienza," Rome, Italy
| | | | - Paolo Maria Rossini
- Department of Neurological, Motor and Sensory Sciences, IRCCS San Raffaele Pisana, Rome, Italy.,Institute of Neurology, Catholic University of The Sacred Heart, Rome, Italy
| | - Luigi De Gennaro
- Department of Psychology, University of Rome "Sapienza," Rome, Italy
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5
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Kong Y, Li K, Fu T, Wan C, Zhang D, Song H, Zhang Y, Liu N, Gan Z, Yuan L. Quercetin ameliorates Aβ toxicity in Drosophila AD model by modulating cell cycle-related protein expression. Oncotarget 2018; 7:67716-67731. [PMID: 27626494 PMCID: PMC5356514 DOI: 10.18632/oncotarget.11963] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 09/01/2016] [Indexed: 12/22/2022] Open
Abstract
Alzheimer's disease (AD) is a prevalent neurodegenerative disorder characterized by β amyloid (Aβ) deposition and neurofibril tangles. It has been reported that a bioflavonoid, quercetin, could ameliorate AD phenotypes in C. elegans and mice. However, the mechanism underlying the ameliorative effect of quercetin is not fully understood yet. Drosophila models could recapitulate AD-like phenotypes, such as shortened lifespan, impaired locomotive ability as well as defects in learning and memory. So in this study, we investigated the effects of quercetin on AD in Drosophila model and explored the underlying mechanisms. We found quercetin could effectively intervene in AD pathogenesis in vivo. Mechanism study showed quercetin could restore the expression of genes perturbed by Aβ accumulation, such as those involved in cell cycle and DNA replication. Cyclin B, an important cell cycle protein, was chosen to test whether it participated in the AD ameliorative effects of quercetin. We found that cyclin B RNAi in the brain could alleviate AD phenotypes. Taken together, the current study suggested that the neuroprotective effects of quercetin were mediated at least partially by targeting cell cycle-related proteins.
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Affiliation(s)
- Yan Kong
- Department of Biochemistry and Molecular Biology, Medical School, Southeast University, Nanjing, Jiangsu, China
| | - Ke Li
- Gladstone Institute of Cardiovascular Disease and Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Tingting Fu
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing, China
| | - Chao Wan
- State Education Ministry's Key Laboratory of Developmental Genes and Human Diseases, Institute of Life Sciences, Southeast University, China
| | - Dongdong Zhang
- State Education Ministry's Key Laboratory of Developmental Genes and Human Diseases, Institute of Life Sciences, Southeast University, China
| | - Hang Song
- State Education Ministry's Key Laboratory of Developmental Genes and Human Diseases, Institute of Life Sciences, Southeast University, China
| | - Yao Zhang
- State Education Ministry's Key Laboratory of Developmental Genes and Human Diseases, Institute of Life Sciences, Southeast University, China
| | - Na Liu
- State Education Ministry's Key Laboratory of Developmental Genes and Human Diseases, Institute of Life Sciences, Southeast University, China
| | - Zhenji Gan
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Nanjing University, Nanjing, China
| | - Liudi Yuan
- Department of Biochemistry and Molecular Biology, Medical School, Southeast University, Nanjing, Jiangsu, China.,State Education Ministry's Key Laboratory of Developmental Genes and Human Diseases, Institute of Life Sciences, Southeast University, China
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6
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Ruland C, Berlandi J, Eikmeier K, Weinert T, Lin FJ, Ambree O, Seggewiss J, Paulus W, Jeibmann A. Decreased cerebral Irp-1B limits impact of social isolation in wild type and Alzheimer's disease modeled in Drosophila melanogaster. GENES BRAIN AND BEHAVIOR 2018; 17:e12451. [PMID: 29251829 DOI: 10.1111/gbb.12451] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 12/13/2017] [Accepted: 12/13/2017] [Indexed: 11/27/2022]
Abstract
Environmental factors, such as housing conditions and cognitively stimulating activities, have been shown to affect behavioral phenotypes and to modulate neurodegenerative conditions such as Alzheimer's disease (AD). AD is a progressive neurodegenerative disorder affecting cognitive functions. Epidemiological evidence and experimental studies using rodent models have indicated that social interaction reduces development and progression of disease. Drosophila models of Aβ42-associated AD lead to AD-like phenotypes, such as long-term memory impairment, locomotor and survival deficits, while effects of environmental conditions on AD-associated phenotypes have not been assessed in the fly. Here, we show that single housing reduced survival and motor performance of Aβ42 expressing and control flies. Gene expression analyses of Aβ42 expressing and control flies that had been exposed to different housing conditions showed upregulation of Iron regulatory protein 1B (Irp-1B) in fly brains following single housing. Downregulating Irp-1B in neurons of single-housed Aβ42 expressing and control flies rescued both survival and motor performance deficits. Thus, we provide novel evidence that increased cerebral expression of Irp-1B may underlie worsened behavioral outcome in socially deprived flies and can additionally modulate AD-like phenotypes.
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Affiliation(s)
- C Ruland
- Institute of Neuropathology, University Hospital Münster, Münster, Germany.,Department of Psychiatry, University of Münster, Münster, Germany
| | - J Berlandi
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - K Eikmeier
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - T Weinert
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - F J Lin
- Department of Biology, Coastal Carolina University, Conway, South Carolina
| | - O Ambree
- Department of Psychiatry, University of Münster, Münster, Germany.,Department of Behavioral Biology, University of Osnabrück, Osnabrück, Germany
| | - J Seggewiss
- Institute for Human Genetics, University Hospital Münster, Münster, Germany
| | - W Paulus
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - A Jeibmann
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
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7
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Sharma N, Khurana N, Muthuraman A. Lower vertebrate and invertebrate models of Alzheimer's disease - A review. Eur J Pharmacol 2017; 815:312-323. [PMID: 28943103 DOI: 10.1016/j.ejphar.2017.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/20/2017] [Accepted: 09/13/2017] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease is a common neurodegenerative disorder which is characterized by the presence of beta- amyloid protein and neurofibrillary tangles (NFTs) in the brain. Till now, various higher vertebrate models have been in use to study the pathophysiology of this disease. But, these models possess some limitations like ethical restrictions, high cost, difficult maintenance of large quantity and lesser reproducibility. Besides, various lower chordate animals like Danio rerio, Drosophila melanogaster, Caenorhabditis elegans and Ciona intestinalis have been proved to be an important model for the in vivo determination of targets of drugs with least limitations. In this article, we reviewed different studies conducted on theses models for the better understanding of the pathophysiology of AD and their subsequent application as a potential tool in the preclinical evaluation of new drugs.
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Affiliation(s)
- Neha Sharma
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Navneet Khurana
- Department of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Arunachalam Muthuraman
- Department of Pharmacology, Akal College of Pharmacy and Technical Education, Mastuana Sahib, Sangrur, Punjab, India; Department of Pharmacology, JSS College of Pharmacy, Jagadguru Sri Shivarathreeshwara University, Mysuru 570015, Karnataka, India.
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8
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Abstract
Mitochondria are among a cell's most vital organelles. They not only produce the majority of the cell's ATP but also play a key role in Ca2+ buffering and apoptotic signaling. While proper allocation of mitochondria is critical to all cells, it is particularly important for the highly polarized neurons. Because mitochondria are mainly synthesized in the soma, they must be transported long distances to be distributed to the far-flung reaches of the neuron-up to 1 m in the case of some human motor neurons. Furthermore, damaged mitochondria can be detrimental to neuronal health, causing oxidative stress and even cell death, therefore the retrograde transport of damaged mitochondria back to the soma for proper disposal, as well as the anterograde transport of fresh mitochondria from the soma to repair damage, are equally critical. Intriguingly, errors in mitochondrial transport have been increasingly implicated in neurological disorders. Here, we describe how to investigate mitochondrial transport in three complementary neuronal systems: cultured induced pluripotent stem cell-derived neurons, cultured rat hippocampal and cortical neurons, and Drosophila larval neurons in vivo. These models allow us to uncover the molecular and cellular mechanisms underlying transport issues that may occur under physiological or pathological conditions.
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9
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Banik A, Brown RE, Bamburg J, Lahiri DK, Khurana D, Friedland RP, Chen W, Ding Y, Mudher A, Padjen AL, Mukaetova-Ladinska E, Ihara M, Srivastava S, Padma Srivastava MV, Masters CL, Kalaria RN, Anand A. Translation of Pre-Clinical Studies into Successful Clinical Trials for Alzheimer's Disease: What are the Roadblocks and How Can They Be Overcome? J Alzheimers Dis 2016; 47:815-43. [PMID: 26401762 DOI: 10.3233/jad-150136] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Preclinical studies are essential for translation to disease treatments and effective use in clinical practice. An undue emphasis on single approaches to Alzheimer's disease (AD) appears to have retarded the pace of translation in the field, and there is much frustration in the public about the lack of an effective treatment. We critically reviewed past literature (1990-2014), analyzed numerous data, and discussed key issues at a consensus conference on Brain Ageing and Dementia to identify and overcome roadblocks in studies intended for translation. We highlight various factors that influence the translation of preclinical research and highlight specific preclinical strategies that have failed to demonstrate efficacy in clinical trials. The field has been hindered by the domination of the amyloid hypothesis in AD pathogenesis while the causative pathways in disease pathology are widely considered to be multifactorial. Understanding the causative events and mechanisms in the pathogenesis are equally important for translation. Greater efforts are necessary to fill in the gaps and overcome a variety of confounds in the generation, study design, testing, and evaluation of animal models and the application to future novel anti-dementia drug trials. A greater variety of potential disease mechanisms must be entertained to enhance progress.
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Affiliation(s)
- Avijit Banik
- Neuroscience Research Lab, Department of Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Richard E Brown
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - James Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Debomoy K Lahiri
- Departments of Psychiatry and of Medical & Molecular Genetics, Indiana University School of Medicine, Neuroscience Research Center, Indianapolis, IN, USA
| | - Dheeraj Khurana
- Neuroscience Research Lab, Department of Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Robert P Friedland
- Department of Neurology, University of Louisville, School of Medicine, Louisville, KY, USA
| | - Wei Chen
- Division of Pulmonary Medicine, Allergy and Immunology, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ying Ding
- Department of Biostatistics, University of Pittsburgh, 318C Parran Hall, Pittsburgh, PA, USA
| | - Amritpal Mudher
- Southampton Neurosciences Group, University of Southampton, Southampton, UK
| | - Ante L Padjen
- Department of Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
| | - Elizabeta Mukaetova-Ladinska
- Institute of Neuroscience, Newcastle University, NIHR Biomedical Research Building, Campus for Ageing and Vitality, Newcastle upon Tyne, UK
| | - Masafumi Ihara
- Department of Stroke and Cerebrovascular Diseases, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Sudhir Srivastava
- Division of Toxicology, Central Drug Research Institute, Lucknow, India
| | - M V Padma Srivastava
- Department of Neurology, Neurosciences Centre, All India Institute of Medical Sciences, New Delhi, India
| | - Colin L Masters
- Mental Health Research Institute, University of Melbourne, Royal Parade, The VIC, Australia
| | - Raj N Kalaria
- Institute of Neuroscience, Newcastle University, NIHR Biomedical Research Building, Campus for Ageing and Vitality, Newcastle upon Tyne, UK
| | - Akshay Anand
- Neuroscience Research Lab, Department of Neurology, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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10
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Zheng ZZ, Chao ML, Fan ZB, Zhao YJ, Song HS. Molecular cloning and characterization of presenilin gene in Bombyx mori. Mol Med Rep 2015; 12:5508-16. [PMID: 26133988 DOI: 10.3892/mmr.2015.4019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 06/05/2015] [Indexed: 11/06/2022] Open
Abstract
Presenilin (PS), the catalytic core of the γ-secretase complex, is considered to be a causative protein of the early‑onset familial form of Alzheimer's disease. Aging is a risk factor for Alzheimer's disease and a number of genetic studies have utilized Bombyx mori (B. mori) as a model, making it possible to use B. mori to investigate Alzheimer's disease. However, the homologous gene of human PS in B. mori has remained to be elucidated. In the present study, the PS homologue gene in B. mori was identified and characterized, and six B. mori presenilin (BmPS) mRNA transcripts were generated by selecting multiple transcription start sites and/or alternative splice sites. The longest mRNA of BmPS (termed BmPS1) contains a 153 nt 5' untranslated region (UTR), a 1,440 nt open reading frame and a 1,063 nt 3' UTR. The predicted protein of BmPS1 consists of 479 amino acid residues and has two highly‑conserved aspartate residues, which form the catalytic core of aspartic proteases. It exhibits a sequence identity of ~44 and 51% with homologues in Homo sapiens and Drosophila melanogaster, respectively. However, the amino acid sequence of the BmPS loop region does not completely match between the two B. mori strains R13Q and Dazao. Genomic analysis revealed that B. mori had a single copy of the BmPS gene, which was composed of 14 exons. A total of four isoforms of BmPS (BmPS‑A, ‑B, ‑C and ‑D) owing to multiple transcriptional start sites and alternative splice sites were identified. The alternative splicing events occurring in the loop region improved the diversity of the BmPS protein and were detectable in all tissues, as determined using reverse transcription quantitative polymerase chain reaction (RT‑qPCR). Furthermore, the expression levels of BmPS in the brain at different developmental stages were detected using RT‑qPCR, and significantly higher expression levels of BmPS were found in the adult stage compared with those in the larval and pupal stages. The present study on BmPS provided insight into the pathogenesis of Alzheimer's disease and mechanisms of silkworm developmental regulation.
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Affiliation(s)
- Zeng-Zhang Zheng
- Department of Neurosciences, School of Life Sciences, Shanghai University, Shanghai 200444, P.R. China
| | - Meng-Ling Chao
- Department of Neurosciences, School of Life Sciences, Shanghai University, Shanghai 200444, P.R. China
| | - Zong-Biao Fan
- Department of Neurosciences, School of Life Sciences, Shanghai University, Shanghai 200444, P.R. China
| | - Yi-Jiao Zhao
- Department of Neurosciences, School of Life Sciences, Shanghai University, Shanghai 200444, P.R. China
| | - Hong-Sheng Song
- Department of Neurosciences, School of Life Sciences, Shanghai University, Shanghai 200444, P.R. China
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11
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Tsou WL, Hosking RR, Burr AA, Sutton JR, Ouyang M, Du X, Gomez CM, Todi SV. DnaJ-1 and karyopherin α3 suppress degeneration in a new Drosophila model of Spinocerebellar Ataxia Type 6. Hum Mol Genet 2015; 24:4385-96. [PMID: 25954029 DOI: 10.1093/hmg/ddv174] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 05/05/2015] [Indexed: 11/15/2022] Open
Abstract
Spinocerebellar ataxia type 6 (SCA6) belongs to the family of CAG/polyglutamine (polyQ)-dependent neurodegenerative disorders. SCA6 is caused by abnormal expansion in a CAG trinucleotide repeat within exon 47 of CACNA1A, a bicistronic gene that encodes α1A, a P/Q-type calcium channel subunit and a C-terminal protein, termed α1ACT. Expansion of the CAG/polyQ region of CACNA1A occurs within α1ACT and leads to ataxia. There are few animal models of SCA6. Here, we describe the generation and characterization of the first Drosophila melanogaster models of SCA6, which express the entire human α1ACT protein with a normal or expanded polyQ. The polyQ-expanded version of α1ACT recapitulates the progressively degenerative nature of SCA6 when expressed in various fly tissues and the presence of densely staining aggregates. Additional studies identify the co-chaperone DnaJ-1 as a potential therapeutic target for SCA6. Expression of DnaJ-1 potently suppresses α1ACT-dependent degeneration and lethality, concomitant with decreased aggregation and reduced nuclear localization of the pathogenic protein. Mutating the nuclear importer karyopherin α3 also leads to reduced toxicity from pathogenic α1ACT. Little is known about the steps leading to degeneration in SCA6 and the means to protect neurons in this disease are lacking. Invertebrate animal models of SCA6 can expand our understanding of molecular sequelae related to degeneration in this disorder and lead to the rapid identification of cellular components that can be targeted to treat it.
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Affiliation(s)
| | | | - Aaron A Burr
- Department of Pharmacology, Cancer Biology Graduate Program and
| | | | | | - Xiaofei Du
- Department of Neurology, University of Chicago School of Medicine, Chicago, IL 60637, USA
| | - Christopher M Gomez
- Department of Neurology, University of Chicago School of Medicine, Chicago, IL 60637, USA
| | - Sokol V Todi
- Department of Pharmacology, Cancer Biology Graduate Program and Department of Neurology, Wayne State University School of Medicine, Detroit, MI 48201, USA and
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12
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Tabuchi M, Lone SR, Liu S, Liu Q, Zhang J, Spira AP, Wu MN. Sleep interacts with aβ to modulate intrinsic neuronal excitability. Curr Biol 2015; 25:702-712. [PMID: 25754641 PMCID: PMC4366315 DOI: 10.1016/j.cub.2015.01.016] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 12/05/2014] [Accepted: 01/06/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND Emerging data suggest an important relationship between sleep and Alzheimer's disease (AD), but how poor sleep promotes the development of AD remains unclear. RESULTS Here, using a Drosophila model of AD, we provide evidence suggesting that changes in neuronal excitability underlie the effects of sleep loss on AD pathogenesis. β-amyloid (Aβ) accumulation leads to reduced and fragmented sleep, while chronic sleep deprivation increases Aβ burden. Moreover, enhancing sleep reduces Aβ deposition. Increasing neuronal excitability phenocopies the effects of reducing sleep on Aβ, and decreasing neuronal activity blocks the elevated Aβ accumulation induced by sleep deprivation. At the single neuron level, we find that chronic sleep deprivation, as well as Aβ expression, enhances intrinsic neuronal excitability. Importantly, these data reveal that sleep loss exacerbates Aβ-induced hyperexcitability and suggest that defects in specific K(+) currents underlie the hyperexcitability caused by sleep loss and Aβ expression. Finally, we show that feeding levetiracetam, an anti-epileptic medication, to Aβ-expressing flies suppresses neuronal excitability and significantly prolongs their lifespan. CONCLUSIONS Our findings directly link sleep loss to changes in neuronal excitability and Aβ accumulation and further suggest that neuronal hyperexcitability is an important mediator of Aβ toxicity. Taken together, these data provide a mechanistic framework for a positive feedback loop, whereby sleep loss and neuronal excitation accelerate the accumulation of Aβ, a key pathogenic step in the development of AD.
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Affiliation(s)
- Masashi Tabuchi
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Shahnaz R Lone
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Sha Liu
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Qili Liu
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Julia Zhang
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Adam P Spira
- Department of Mental Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Mark N Wu
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21205, USA; Department of Neuroscience, Johns Hopkins University, Baltimore, MD 21205, USA.
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13
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Hu Y, Han Y, Shao Y, Wang X, Ma Y, Ling E, Xue L. Gr33a modulates Drosophila male courtship preference. Sci Rep 2015; 5:7777. [PMID: 25586066 PMCID: PMC4648378 DOI: 10.1038/srep07777] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 12/10/2014] [Indexed: 11/30/2022] Open
Abstract
In any gamogenetic species, attraction between individuals of the opposite sex promotes reproductive success that guarantees their thriving. Consequently, mate determination between two sexes is effortless for an animal. However, choosing a spouse from numerous attractive partners of the opposite sex needs deliberation. In Drosophila melanogaster, both younger virgin females and older ones are equally liked options to males; nevertheless, when given options, males prefer younger females to older ones. Non-volatile cuticular hydrocarbons, considered as major pheromones in Drosophila, constitute females' sexual attraction that act through males' gustatory receptors (Grs) to elicit male courtship. To date, only a few putative Grs are known to play roles in male courtship. Here we report that loss of Gr33a function or abrogating the activity of Gr33a neurons does not disrupt male-female courtship, but eliminates males' preference for younger mates. Furthermore, ectopic expression of human amyloid precursor protein (APP) in Gr33a neurons abolishes males' preference behavior. Such function of APP is mediated by the transcription factor forkhead box O (dFoxO). These results not only provide mechanistic insights into Drosophila male courtship preference, but also establish a novel Drosophila model for Alzheimer's disease (AD).
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Affiliation(s)
- Yujia Hu
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yi Han
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yingyao Shao
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Xingjun Wang
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Yeqing Ma
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
| | - Erjun Ling
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lei Xue
- Department of Interventional Radiology, Shanghai 10th People's Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Science and Technology, Tongji University, Shanghai 200092, China
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14
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Mhatre SD, Michelson SJ, Gomes J, Tabb LP, Saunders AJ, Marenda DR. Development and characterization of an aged onset model of Alzheimer's disease in Drosophila melanogaster. Exp Neurol 2014; 261:772-81. [DOI: 10.1016/j.expneurol.2014.08.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 08/14/2014] [Accepted: 08/19/2014] [Indexed: 01/08/2023]
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15
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Prüßing K, Voigt A, Schulz JB. Drosophila melanogaster as a model organism for Alzheimer's disease. Mol Neurodegener 2013; 8:35. [PMID: 24267573 PMCID: PMC4222597 DOI: 10.1186/1750-1326-8-35] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 11/13/2013] [Indexed: 02/05/2023] Open
Abstract
Drosophila melanogaster provides an important resource for in vivo modifier screens of neurodegenerative diseases. To study the underlying pathogenesis of Alzheimer’s disease, fly models that address Tau or amyloid toxicity have been developed. Overexpression of human wild-type or mutant Tau causes age-dependent neurodegeneration, axonal transport defects and early death. Large-scale screens utilizing a neurodegenerative phenotype induced by eye-specific overexpression of human Tau have identified several kinases and phosphatases, apoptotic regulators and cytoskeleton proteins as determinants of Tau toxicity in vivo. The APP ortholog of Drosophila (dAPPl) shares the characteristic domains with vertebrate APP family members, but does not contain the human Aβ42 domain. To circumvent this drawback, researches have developed strategies by either direct secretion of human Aβ42 or triple transgenic flies expressing human APP, β-secretase and Drosophila γ-secretase presenilin (dPsn). Here, we provide a brief overview of how fly models of AD have contributed to our knowledge of the pathomechanisms of disease.
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Affiliation(s)
- Katja Prüßing
- Department of Neurology, University Medical Center, RWTH Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany.
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16
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Rahn T, Leippe M, Roeder T, Fedders H. EGFR signaling in the brain is necessary for olfactory learning in Drosophila larvae. Learn Mem 2013; 20:194-200. [PMID: 23512935 DOI: 10.1101/lm.029934.112] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Signaling via the epidermal growth factor receptor (EGFR) pathway has emerged as one of the key mechanisms in the development of the central nervous system in Drosophila melanogaster. By contrast, little is known about the functions of EGFR signaling in the differentiated larval brain. Here, promoter-reporter lines of EGFR and its most prominent activating ligands, Spitz, Keren, and Vein, were used to identify the brain structures relevant for the EGFR pathway. Unexpectedly, promoter activity of all these pathway components was found in the mushroom bodies, which are known to be a higher brain center required for olfactory learning. We investigated the role of the EGFR pathway in this process by using different mutant larvae with reduced pan-neuronal EGFR signaling and those with reduced EGFR signaling in mushroom bodies only. Expression of a dominant-negative form of EGFR as well as silencing of the ligands via RNA interference was applied and resulted in significantly impaired olfactory learning performances. General defects in the ability to taste or smell as well as impaired EGFR signaling during embryonic development could be excluded as major reasons for this learning phenotype. In addition, targeted expression of a constitutively active form of the ligand Spitz also led to a significantly reduced learning ability. Thus, very low levels as well as very high levels of EGFR signaling are deleterious for olfactory learning and memory formation. We hypothesize that EGFR signaling in a certain range maintains a homeostatic situation in the mushroom bodies that is necessary for proper learning and memory.
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Affiliation(s)
- Tasja Rahn
- Zoological Institute, Zoophysiology, University of Kiel, 24098 Kiel, Germany
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17
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Jaiswal M, Sandoval H, Zhang K, Bayat V, Bellen HJ. Probing mechanisms that underlie human neurodegenerative diseases in Drosophila. Annu Rev Genet 2012; 46:371-96. [PMID: 22974305 DOI: 10.1146/annurev-genet-110711-155456] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The fruit fly, Drosophila melanogaster, is an excellent organism for the study of the genetic and molecular basis of metazoan development. Drosophila provides numerous tools and reagents to unravel the molecular and cellular functions of genes that cause human disease, and the past decade has witnessed a significant expansion of the study of neurodegenerative disease mechanisms in flies. Here we review the interplay between oxidative stress and neuronal toxicity. We cover some of the studies that show how proteasome degradation of protein aggregates, autophagy, mitophagy, and lysosomal function affect the quality control mechanisms required for neuronal survival. We discuss how forward genetic screens in flies have led to the isolation of a few loci that cause neurodegeneration, paving the way for large-scale systematic screens to identify such loci in flies as well as promoting gene discovery in humans.
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Affiliation(s)
- M Jaiswal
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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18
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Molecular mechanisms of aging and immune system regulation in Drosophila. Int J Mol Sci 2012; 13:9826-9844. [PMID: 22949833 PMCID: PMC3431831 DOI: 10.3390/ijms13089826] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 07/25/2012] [Accepted: 07/30/2012] [Indexed: 12/04/2022] Open
Abstract
Aging is a complex process that involves the accumulation of deleterious changes resulting in overall decline in several vital functions, leading to the progressive deterioration in physiological condition of the organism and eventually causing disease and death. The immune system is the most important host-defense mechanism in humans and is also highly conserved in insects. Extensive research in vertebrates has concluded that aging of the immune function results in increased susceptibility to infectious disease and chronic inflammation. Over the years, interest has grown in studying the molecular interaction between aging and the immune response to pathogenic infections. The fruit fly Drosophila melanogaster is an excellent model system for dissecting the genetic and genomic basis of important biological processes, such as aging and the innate immune system, and deciphering parallel mechanisms in vertebrate animals. Here, we review the recent advances in the identification of key players modulating the relationship between molecular aging networks and immune signal transduction pathways in the fly. Understanding the details of the molecular events involved in aging and immune system regulation will potentially lead to the development of strategies for decreasing the impact of age-related diseases, thus improving human health and life span.
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19
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The bad, the good, and the ugly about oxidative stress. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2012; 2012:163913. [PMID: 22619696 PMCID: PMC3350994 DOI: 10.1155/2012/163913] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 01/16/2012] [Accepted: 02/07/2012] [Indexed: 01/07/2023]
Abstract
Alzheimer's disease (AD), Parkinson's disease (PD), and cancer (e.g., leukemia) are the most devastating disorders affecting millions of people worldwide. Except for some kind of cancers, no effective and/or definitive therapeutic treatment aimed to reduce or to retard the clinic and pathologic symptoms induced by AD and PD is presently available. Therefore, it is urgently needed to understand the molecular basis of these disorders. Since oxidative stress (OS) is an important etiologic factor of the pathologic process of AD, PD, and cancer, understanding how intracellular signaling pathways respond to OS will have a significant implication in the therapy of these diseases. Here, we propose a model of minimal completeness of cell death signaling induced by OS as a mechanistic explanation of neuronal and cancer cell demise. This mechanism might provide the basis for therapeutic design strategies. Finally, we will attempt to associate PD, cancer, and OS. This paper critically analyzes the evidence that support the “oxidative stress model” in neurodegeneration and cancer.
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20
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Iliadi KG, Knight D, Boulianne GL. Healthy aging - insights from Drosophila. Front Physiol 2012; 3:106. [PMID: 22529821 PMCID: PMC3328947 DOI: 10.3389/fphys.2012.00106] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 04/03/2012] [Indexed: 11/13/2022] Open
Abstract
Human life expectancy has nearly doubled in the past century due, in part, to social and economic development, and a wide range of new medical technologies and treatments. As the number of elderly increase it becomes of vital importance to understand what factors contribute to healthy aging. Human longevity is a complex process that is affected by both environmental and genetic factors and interactions between them. Unfortunately, it is currently difficult to identify the role of genetic components in human longevity. In contrast, model organisms such as C. elegans, Drosophila, and rodents have facilitated the search for specific genes that affect lifespan. Experimental evidence obtained from studies in model organisms suggests that mutations in a single gene may increase longevity and delay the onset of age-related symptoms including motor impairments, sexual and reproductive and immune dysfunction, cardiovascular disease, and cognitive decline. Furthermore, the high degree of conservation between diverse species in the genes and pathways that regulate longevity suggests that work in model organisms can both expand our theoretical knowledge of aging and perhaps provide new therapeutic targets for the treatment of age-related disorders.
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Affiliation(s)
- Konstantin G Iliadi
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children Toronto, ON, Canada
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21
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Characterization of a Drosophila Alzheimer's disease model: pharmacological rescue of cognitive defects. PLoS One 2011; 6:e20799. [PMID: 21673973 PMCID: PMC3108982 DOI: 10.1371/journal.pone.0020799] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 05/13/2011] [Indexed: 02/07/2023] Open
Abstract
Transgenic models of Alzheimer's disease (AD) have made significant contributions to our understanding of AD pathogenesis, and are useful tools in the development of potential therapeutics. The fruit fly, Drosophila melanogaster, provides a genetically tractable, powerful system to study the biochemical, genetic, environmental, and behavioral aspects of complex human diseases, including AD. In an effort to model AD, we over-expressed human APP and BACE genes in the Drosophila central nervous system. Biochemical, neuroanatomical, and behavioral analyses indicate that these flies exhibit aspects of clinical AD neuropathology and symptomology. These include the generation of Aβ40 and Aβ42, the presence of amyloid aggregates, dramatic neuroanatomical changes, defects in motor reflex behavior, and defects in memory. In addition, these flies exhibit external morphological abnormalities. Treatment with a γ-secretase inhibitor suppressed these phenotypes. Further, all of these phenotypes are present within the first few days of adult fly life. Taken together these data demonstrate that this transgenic AD model can serve as a powerful tool for the identification of AD therapeutic interventions.
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