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Daidzein Augments Cholesterol Homeostasis via ApoE to Promote Functional Recovery in Chronic Stroke. J Neurosci 2016; 35:15113-26. [PMID: 26558782 DOI: 10.1523/jneurosci.2890-15.2015] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Stroke is the world's leading cause of physiological disability, but there are currently no available agents that can be delivered early after stroke to enhance recovery. Daidzein, a soy isoflavone, is a clinically approved agent that has a neuroprotective effect in vitro, and it promotes axon growth in an animal model of optic nerve crush. The current study investigates the efficacy of daidzein on neuroprotection and functional recovery in a clinically relevant mouse model of stroke recovery. In light of the fact that cholesterols are essential lipid substrates in injury-induced synaptic remodeling, we found that daidzein enhanced the cholesterol homeostasis genetic program, including Lxr and downstream transporters, Apoe, Abca1, and Abcg1 genes in vitro. Daidzein also elevated the cholesterol homeostasis genes in the poststroke brain with Apoe, the highest expressing transporter, but did not affect infarct volume or hemispheric swelling. Despite the absence of neuroprotection, daidzein improved motor/gait function in chronic stroke and elevated synaptophysin expression. However, the daidzein-enhanced functional benefits and synaptophysin expression were abolished in Apoe-knock-out mice, suggesting the importance of daidzein-induced ApoE upregulation in fostering stroke recovery. Dissociation between daidzein-induced functional benefits and the absence of neuroprotection further suggest the presence of nonoverlapping mechanisms underlying recovery processes versus acute pathology. With its known safety in humans, early and chronic use of daidzein aimed at augmenting ApoE may serve as a novel, translatable strategy to promote functional recovery in stroke patients without adverse acute effect. SIGNIFICANCE STATEMENT There have been recurring translational failures in treatment strategies for stroke. One underlying issue is the disparity in outcome analysis between animal and clinical studies. The former mainly depends on acute infarct size, whereas long-term functional recovery is an important outcome in patients. In an attempt to identify agents that promote functional recovery, we discovered that an FDA-approved soy isoflavone, daidzein, improved stroke-induced behavioral deficits via enhancing cholesterol homeostasis in chronic stroke, and this occurs without causing adverse effects in the acute phase. With its known safety in humans, the study suggests that the early and chronic use of daidzein serves as a potential strategy to promote functional recovery in stroke patients.
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Small molecule TBTC as a new selective retinoid X receptor α agonist improves behavioral deficit in Alzheimer's disease model mice. Eur J Pharmacol 2015; 762:202-13. [DOI: 10.1016/j.ejphar.2015.05.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 04/27/2015] [Accepted: 05/26/2015] [Indexed: 11/22/2022]
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Shadfar S, Hwang CJ, Lim MS, Choi DY, Hong JT. Involvement of inflammation in Alzheimer’s disease pathogenesis and therapeutic potential of anti-inflammatory agents. Arch Pharm Res 2015; 38:2106-19. [DOI: 10.1007/s12272-015-0648-x] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 08/08/2015] [Indexed: 02/06/2023]
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Balducci C, Paladini A, Micotti E, Tolomeo D, La Vitola P, Grigoli E, Richardson JC, Forloni G. The Continuing Failure of Bexarotene in Alzheimer’s Disease Mice. J Alzheimers Dis 2015; 46:471-82. [DOI: 10.3233/jad-150029] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Claudia Balducci
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Alessandra Paladini
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Edoardo Micotti
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Daniele Tolomeo
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Pietro La Vitola
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Emanuele Grigoli
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
| | - Jill C. Richardson
- Neurosciences Therapeutic Unit, GlaxoSmithKline, Gunnels Wood Road, Stevenage, Herts, UK
| | - Gianluigi Forloni
- Laboratory of Biology of Neurodegenerative Disorders, Department of Neuroscience, IRCCS Mario Negri Institute for Pharmacological Research, Milano, Italy
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Zhao XS, Fu WY, Hung KW, Chien WWY, Li Z, Fu AK, Ip NY. NRC-interacting factor directs neurite outgrowth in an activity-dependent manner. Neuroscience 2015; 289:207-13. [PMID: 25573434 DOI: 10.1016/j.neuroscience.2014.12.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 12/05/2014] [Accepted: 12/24/2014] [Indexed: 11/18/2022]
Abstract
Nuclear hormone receptor coregulator-interacting factor 1 (NIF-1) is a zinc finger nuclear protein that was initially identified to enhance nuclear hormone receptor transcription via its interaction with nuclear hormone receptor coregulator (NRC). NIF-1 may regulate gene transcription either by modulating general transcriptional machinery or remodeling chromatin structure through interactions with specific protein partners. We previously reported that the cytoplasmic/nuclear localization of NIF-1 is regulated by the neuronal Cdk5 activator p35, suggesting potential neuronal functions for NIF-1. The present study reveals that NIF-1 plays critical roles in regulating neuronal morphogenesis at early stages. NIF-1 was prominently expressed in the nuclei of developing rat cortical neurons. Knockdown of NIF-1 expression attenuated both neurite outgrowth in cultured cortical neurons and retinoic acid (RA)-treated Neuro-2a neuroblastoma cells. Furthermore, activity-induced Ca(2+) influx, which is critical for neuronal morphogenesis, stimulated the nuclear localization of NIF-1 in cortical neurons. Suppression of NIF-1 expression reduced the up-regulation of neuronal activity-dependent gene transcription. These findings collectively suggest that NIF-1 directs neuronal morphogenesis during early developmental stages through modulating activity-dependent gene transcription.
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Affiliation(s)
- X-S Zhao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - W-Y Fu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - K-W Hung
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - W W Y Chien
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Z Li
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - A K Fu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - N Y Ip
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Molecular Neuroscience Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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56
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Chang KL, Pee HN, Yang S, Ho PC. Influence of drug transporters and stereoselectivity on the brain penetration of pioglitazone as a potential medicine against Alzheimer's disease. Sci Rep 2015; 5:9000. [PMID: 25760794 PMCID: PMC5390903 DOI: 10.1038/srep09000] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 02/12/2015] [Indexed: 11/26/2022] Open
Abstract
Pioglitazone is currently undergoing clinical trials for treatment of Alzheimer's disease (AD). However, poor brain penetration remains an obstacle to development of the drug for such intended clinical uses. In this study, we demonstrate that the inhibition of P-glycoprotein (P-gp) significantly increases brain penetration of pioglitazone, whereas inhibition of breast cancer resistance protein (BCRP) has little effect. We also investigate the stereoselectivity of pioglitazone uptake in the brain. When mice were dosed with racemic pioglitazone, the concentration of (+)-pioglitazone was 46.6% higher than that of (-)-pioglitazone in brain tissue and 67.7% lower than that of (-)-pioglitazone in plasma. Dosing mice with pure (+)-pioglitazone led to a 76% increase in brain exposure levels compared to those from an equivalent dose of racemic pioglitazone. Pure (+)-pioglitazone was also shown to have comparable amyloid-lowering capabilities to the racemic pioglitazone in an in vitro AD model. These results suggest that P-gp may act as a stereoselective barrier to prevent pioglitazone entry into the brain. Dosing with (+)-pioglitazone instead of the racemic mixture may result in higher levels of brain exposure to pioglitazone, thus potentially improving the development of pioglitazone treatment of AD.
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Affiliation(s)
- Kai Lun Chang
- 1] Department of Pharmacy, Faculty of Science, National University of Singapore, Republic of Singapore [2] Computational and Systems Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Hai Ning Pee
- Department of Pharmacy, Faculty of Science, National University of Singapore, Republic of Singapore
| | - Shili Yang
- Department of Pharmacy, Faculty of Science, National University of Singapore, Republic of Singapore
| | - Paul C Ho
- Department of Pharmacy, Faculty of Science, National University of Singapore, Republic of Singapore
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57
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Strobel S, Grünblatt E, Riederer P, Heinsen H, Arzberger T, Al-Sarraj S, Troakes C, Ferrer I, Monoranu CM. Changes in the expression of genes related to neuroinflammation over the course of sporadic Alzheimer's disease progression: CX3CL1, TREM2, and PPARγ. J Neural Transm (Vienna) 2015; 122:1069-76. [PMID: 25596843 DOI: 10.1007/s00702-015-1369-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 01/12/2015] [Indexed: 12/28/2022]
Abstract
The role of neuroinflammation in the pathogenesis of neurodegenerative diseases has become more evident in recent years. Research on the etiology and pathogenesis of sporadic Alzheimer's disease (AD) has focused on the role of chemokines such as CX3CL1, on the triggering receptors expressed by myeloid cells (TREMs), especially TREM2, and on the transcription factor/nuclear hormone receptor peroxisome proliferator-activated receptor gamma (PPARγ). Here we analyzed the expression levels of CX3CL1, TREM2, and PPARγ in tissue homogenates from human brain regions that have different degrees of vulnerability to neuropathological AD-related changes to obtain insights into the pathogenesis and progression of AD. We found that CX3CL1 and TREM2, two genes related to neuroinflammation, are more highly expressed in brain regions with pronounced vulnerability to AD-related changes, such as the hippocampus, and that the expression levels reflect the course of the disease, whereas regions with low vulnerability to AD, seemed generally less affected by neuroinflammation. Furthermore, our results support previous findings of significantly higher CX3CL1 plasma levels in patients with mild to moderate AD than in patients with severe AD. Thus, CX3CL1 should be considered as promising additional marker for the early diagnosis of AD and underlines once more, the involvement of the neuroinflammation in the pathogenesis of this neurodegenerative disease.
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Affiliation(s)
- S Strobel
- Department of Neuropathology, Institute of Pathology, University of Wuerzburg, Josef-Schneider-Str. 2, 97080, Wuerzburg, Germany
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58
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Tousi B. The emerging role of bexarotene in the treatment of Alzheimer's disease: current evidence. Neuropsychiatr Dis Treat 2015; 11:311-5. [PMID: 25709453 PMCID: PMC4327563 DOI: 10.2147/ndt.s61309] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In 2012, a novel approach to the treatment of Alzheimer's disease was introduced, heralding a wave of excitement in the field of dementia. Bexarotene, a retinoid X receptor agonist, was shown to reverse neurodegeneration, improve cognition, and decrease levels of amyloid-β in transgenic mice expressing familial Alzheimer disease mutations. Since then, there has been widespread discussion about bexarotene, as well as a number of follow-up studies. Bexarotene is a unique compound, as it is approved by the US Food and Drug Administration for other purposes and there are reasonable data to justify its mechanism of action in dementia. This review discusses these studies and the emerging role of bexarotene in the clinical field of Alzheimer's dementia.
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Affiliation(s)
- Babak Tousi
- Cleveland Clinic Lou Ruvo Center for Brian Health, Neurological Institute, Cleveland, OH, USA
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59
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Skerrett R, Malm T, Landreth G. Nuclear receptors in neurodegenerative diseases. Neurobiol Dis 2014; 72 Pt A:104-16. [PMID: 24874548 PMCID: PMC4246019 DOI: 10.1016/j.nbd.2014.05.019] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/14/2014] [Accepted: 05/17/2014] [Indexed: 01/04/2023] Open
Abstract
Nuclear receptors have generated substantial interest in the past decade as potential therapeutic targets for the treatment of neurodegenerative disorders. Despite years of effort, effective treatments for progressive neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and ALS remain elusive, making non-classical drug targets such as nuclear receptors an attractive alternative. A substantial literature in mouse models of disease and several clinical trials have investigated the role of nuclear receptors in various neurodegenerative disorders, most prominently AD. These studies have met with mixed results, yet the majority of studies in mouse models report positive outcomes. The mechanisms by which nuclear receptor agonists affect disease pathology remain unclear. Deciphering the complex signaling underlying nuclear receptor action in neurodegenerative diseases is essential for understanding this variability in preclinical studies, and for the successful translation of nuclear receptor agonists into clinical therapies.
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Affiliation(s)
- Rebecca Skerrett
- Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA.
| | - Tarja Malm
- Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA; A.I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Neulaniementie 2, 70211 Kuopio, Finland.
| | - Gary Landreth
- Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA.
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60
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Fattori J, Indolfo NDC, Campos JCLDO, Videira NB, Bridi AV, Doratioto TR, Assis MAD, Figueira ACM. Investigation of Interactions between DNA and Nuclear Receptors: A Review of the Most Used Methods. NUCLEAR RECEPTOR RESEARCH 2014. [DOI: 10.11131/2014/101090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Juliana Fattori
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
| | - Nathalia de Carvalho Indolfo
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
| | | | - Natália Bernardi Videira
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
| | - Aline Villanova Bridi
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
| | - Tábata Renée Doratioto
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
| | - Michelle Alexandrino de Assis
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
| | - Ana Carolina Migliorini Figueira
- Brazilian Biosciences National Laboratory (LNBio), Brazilian Center for Research in Energy and Materials (CNPEM), P.O. Box 6192, Campinas-SP, Brazil
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61
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Insulin resistance in Alzheimer's disease. Neurobiol Dis 2014; 72 Pt A:92-103. [PMID: 25237037 DOI: 10.1016/j.nbd.2014.09.001] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 09/02/2014] [Accepted: 09/05/2014] [Indexed: 12/16/2022] Open
Abstract
Insulin is a key hormone regulating metabolism. Insulin binding to cell surface insulin receptors engages many signaling intermediates operating in parallel and in series to control glucose, energy, and lipids while also regulating mitogenesis and development. Perturbations in the function of any of these intermediates, which occur in a variety of diseases, cause reduced sensitivity to insulin and insulin resistance with consequent metabolic dysfunction. Chronic inflammation ensues which exacerbates compromised metabolic homeostasis. Since insulin has a key role in learning and memory as well as directly regulating ERK, a kinase required for the type of learning and memory compromised in early Alzheimer's disease (AD), insulin resistance has been identified as a major risk factor for the onset of AD. Animal models of AD or insulin resistance or both demonstrate that AD pathology and impaired insulin signaling form a reciprocal relationship. Of note are human and animal model studies geared toward improving insulin resistance that have led to the identification of the nuclear receptor and transcription factor, peroxisome proliferator-activated receptor gamma (PPARγ) as an intervention tool for early AD. Strategic targeting of alternate nodes within the insulin signaling network has revealed disease-stage therapeutic windows in animal models that coalesce with previous and ongoing clinical trial approaches. Thus, exploiting the connection between insulin resistance and AD provides powerful opportunities to delineate therapeutic interventions that slow or block the pathogenesis of AD.
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Abstract
Blood cholesterol levels are not consistently elevated in subjects with age-related cognitive decline, although epidemiological studies suggest that Alzheimer's disease and cardiovascular diseases share common risk factors. These include the presence of an unusual genetic variant, the APOE4 (apolipoprotein E4) allele, which modulates LDL (low-density lipoproteins) metabolism, increases free radical formation and reduces plasma antioxidant concentrations. Together, these risk factors support a mechanism for increased LDL circulation time and free radical modification of LDL. Plasma oxycholesterols, hydroxylated metabolites of cholesterol, are carried by oxidized LDL, and elevated lipids in mid-life are associated with increased long-term risk of dementia. Although brain cholesterol metabolism is segregated from the systemic circulation, during oxidative stress, plasma oxycholesterols could have damaging effects on BBB (blood–brain barrier) function and consequently on neuronal cells. Cholesterol-lowering drugs such as statins may prevent the modifications to LDL in mid-life and might show beneficial effects in later life.
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63
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Aicardi G. New hope from an old drug: fighting Alzheimer's disease with the cancer drug bexarotene (targretin)? Rejuvenation Res 2014; 16:524-8. [PMID: 24047423 DOI: 10.1089/rej.2013.1497] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Despite decades of research, there is no cure for Alzheimer disease (AD), and current pharmacological treatments only partially mask the symptoms while the disease progresses within the brain. AD is associated with impaired clearance of β-amyloid (Aβ) from the brain, a process facilitated by apolipoprotein E (ApoE), whose expression is transcriptionally regulated by the ligand-activated nuclear receptors peroxisome proliferator-activated receptor-γ (PPARγ) and liver X receptor (LXR), in conjunction with retinoid X receptor (RXR). A very interesting study performed by G.E. Landreth's group in three murine models of AD has shown that the RXR agonist bexarotene (Targretin), Food and Drug Administration (FDA) approved and used since 1999 for the treatment of cutaneous T cell lymphoma, promotes a fast ApoE-dependent clearance of soluble Aβ peptides from the brain, reduces Aβ plaques, and stimulates the reversal of cognitive, social, and olfactory deficits. Four independent studies tried to replicate these observations; the clearance of soluble Aβ peptides and the reversal of cognitive deficits were replicated in two studies, but all of the studies failed to replicate the reduction of Aβ plaques. In a second report, G.E. Landreth's group formulates some hypotheses to explain these discrepancies. Although observations in mouse models of AD might not necessarily extrapolate to humans, bexarotene is a very interesting potential drug against AD; phase I and II clinical trials are under way.
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Affiliation(s)
- Giorgio Aicardi
- Department for Life Quality Studies, and Interdepartmental Center ''L.Galvani'' for the study of Biophysics, Bioinformatics and Biocomplexity, University of Bologna , Bologna, Italy
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64
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Sodhi RK, Singh N. Liver X receptor agonist T0901317 reduces neuropathological changes and improves memory in mouse models of experimental dementia. Eur J Pharmacol 2014; 732:50-9. [DOI: 10.1016/j.ejphar.2014.03.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 03/13/2014] [Accepted: 03/20/2014] [Indexed: 01/08/2023]
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PPARγ recruitment to active ERK during memory consolidation is required for Alzheimer's disease-related cognitive enhancement. J Neurosci 2014; 34:4054-63. [PMID: 24623782 DOI: 10.1523/jneurosci.4024-13.2014] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cognitive impairment is a quintessential feature of Alzheimer's disease (AD) and AD mouse models. The peroxisome proliferator-activated receptor-γ (PPARγ) agonist rosiglitazone improves hippocampus-dependent cognitive deficits in some AD patients and ameliorates deficits in the Tg2576 mouse model for AD amyloidosis. Tg2576 cognitive enhancement occurs through the induction of a gene and protein expression profile reflecting convergence of the PPARγ signaling axis and the extracellular signal-regulated protein kinase (ERK) cascade, a critical mediator of memory consolidation. We therefore tested whether PPARγ and ERK associated in protein complexes that subserve cognitive enhancement through PPARγ agonism. Coimmunoprecipitation of hippocampal extracts revealed that PPARγ and activated, phosphorylated ERK (pERK) associated in Tg2576 in vivo, and that PPARγ agonism facilitated recruitment of PPARγ to pERK during memory consolidation. Furthermore, the amount of PPARγ recruited to pERK correlated with the cognitive reserve in humans with AD and in Tg2576. Our findings implicate a previously unidentified PPARγ-pERK complex that provides a molecular mechanism for the convergence of these pathways during cognitive enhancement, thereby offering new targets for therapeutic development in AD.
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66
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Hauser PS, Ryan RO. Impact of apolipoprotein E on Alzheimer's disease. Curr Alzheimer Res 2014; 10:809-17. [PMID: 23919769 DOI: 10.2174/15672050113109990156] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 05/10/2013] [Accepted: 05/12/2013] [Indexed: 11/22/2022]
Abstract
A key feature of Alzheimer's disease (AD) is deposition of extracellular amyloid plaque comprised chiefly of the amyloid β (Aβ) peptide. Studies of Aβ have shown that it may be catabolized by proteolysis or cleared from brain via members of the low-density lipoprotein receptor family. Alternatively, Aβ can undergo a conformational transition from α-helix to β-sheet, a conformer that displays a propensity to self-associate, oligomerize and form fibrils. Furthermore, β- sheet conformers catalyze conversion of other α-helical Aβ peptides to β-sheet, feeding the oligomer and fibril assembly process. A factor that influences the fate of Aβ in the extracellular space is apolipoprotein (apo) E. Polymorphism at position 112 or 158 in apoE give rise to three major isoforms. One isoform in particular, apoE4 (Arg at 112 and 158), has generated considerable interest since the discovery that it is the major genetic risk factor for development of late onset AD. Despite this striking correlation, the molecular mechanism underlying apoE4's association with AD remains unclear. A tertiary structural feature distinguishing apoE4 from apoE2 and apoE3, termed domain interaction, is postulated to affect the conformation and orientation of its' two independently folded domains. This feature has the potential to influence apoE4's interaction with Aβ, its sensitivity to proteolysis or its lipid accrual and receptor binding activities. Thus, domain interaction may constitute the principal molecular feature of apoE4 that predisposes carriers to late onset AD. By understanding the contribution of apoE4 to AD at the molecular level new therapeutic or prevention strategies will emerge.
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Affiliation(s)
- Paul S Hauser
- Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609 USA.
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Léger GC, Massoud F. Novel disease-modifying therapeutics for the treatment of Alzheimer’s disease. Expert Rev Clin Pharmacol 2014; 6:423-42. [DOI: 10.1586/17512433.2013.811237] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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68
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Natunen T, Martiskainen H, Sarajärvi T, Helisalmi S, Pursiheimo JP, Viswanathan J, Laitinen M, Mäkinen P, Kauppinen T, Rauramaa T, Leinonen V, Alafuzoff I, Haapasalo A, Soininen H, Hiltunen M. Effects of NR1H3 genetic variation on the expression of liver X receptor α and the progression of Alzheimer's disease. PLoS One 2013; 8:e80700. [PMID: 24278306 PMCID: PMC3835410 DOI: 10.1371/journal.pone.0080700] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 10/16/2013] [Indexed: 01/19/2023] Open
Abstract
Alzheimer's disease (AD) has been postulated to involve defects in the clearance of amyloid-β (Aβ). Activation of liver X receptor α (LXRα) increases the expression of apolipoprotein E (ApoE) as well as cholesterol transporters ABCA1 and ABCG1, leading to augmented clearance of Aβ. We have previously shown that the C allele of rs7120118 in the NR1H3 gene encoding LXRα reduces the risk of AD. Here, we wanted to assess whether the rs7120118 variation affects the progression of AD and modulates the expression of NR1H3 and its downstream targets APOE, ABCA1 and ABCG1.We utilized tissue samples from the inferior temporal cortex of 87 subjects, which were subdivided according to Braak staging into mild, moderate and severe AD groups on the basis of AD-related neurofibrillary pathology. APOE ε4 allele increased soluble Aβ42 levels in the tissue samples in a dose-dependent manner, but did not affect the expression status of APOE. In contrast, the CC genotype of rs7120118 was underrepresented in the severe group, although this result did not reach statistical significance. Also, patients with the CC genotype of rs7120118 showed significantly decreased soluble Aβ42 levels as compared to the patients with TT genotype. Although the severity of AD did not affect NR1H3 expression, the mRNA levels of NR1H3 among the patients with CT genotype of rs7120118 were significantly increased as compared to the patients with TT genotype. These results suggest that genetic variation in NR1H3 modulates the expression of LXRα and the levels of soluble Aβ42.
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Affiliation(s)
- Teemu Natunen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Henna Martiskainen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Timo Sarajärvi
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Seppo Helisalmi
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | | | - Jayashree Viswanathan
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Marjo Laitinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Petra Mäkinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Tarja Kauppinen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Tuomas Rauramaa
- Department of Pathology, Kuopio University Hospital, Finland and Institute of Clinical Medicine, Unit of Pathology, University of Eastern Finland, Kuopio, Finland
| | - Ville Leinonen
- Institute of Clinical Medicine – Neurosurgery, University of Eastern Finland and Neurosurgery of NeuroCenter, Kuopio University Hospital, Kuopio, Finland
| | - Irina Alafuzoff
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Annakaisa Haapasalo
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Hilkka Soininen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Mikko Hiltunen
- Institute of Clinical Medicine – Neurology, University of Eastern Finland and Department of Neurology, Kuopio University Hospital, Kuopio, Finland
- * E-mail:
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69
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Chen XF, Zhang YW, Xu H, Bu G. Transcriptional regulation and its misregulation in Alzheimer's disease. Mol Brain 2013; 6:44. [PMID: 24144318 PMCID: PMC3854070 DOI: 10.1186/1756-6606-6-44] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 10/15/2013] [Indexed: 11/25/2022] Open
Abstract
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder characterized by loss of memory and cognitive function. A key neuropathological event in AD is the accumulation of amyloid-β (Aβ) peptide. The production and clearance of Aβ in the brain are regulated by a large group of genes. The expression levels of these genes must be fine-tuned in the brain to keep Aβ at a balanced amount under physiological condition. Misregulation of AD genes has been found to either increase AD risk or accelerate the disease progression. In recent years, important progress has been made in uncovering the regulatory elements and transcriptional factors that guide the expression of these genes. In this review, we describe the mechanisms of transcriptional regulation for the known AD genes and the misregualtion that leads to AD susceptibility.
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Affiliation(s)
- Xiao-Fen Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, 361102 Xiamen, Fujian, People's Republic of China.
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70
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Kiss M, Czimmerer Z, Nagy L. The role of lipid-activated nuclear receptors in shaping macrophage and dendritic cell function: From physiology to pathology. J Allergy Clin Immunol 2013; 132:264-86. [PMID: 23905916 DOI: 10.1016/j.jaci.2013.05.044] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/16/2013] [Accepted: 05/30/2013] [Indexed: 02/06/2023]
Abstract
Nuclear receptors are ligand-activated transcription factors linking lipid signaling to the expression of the genome. There is increasing appreciation of the involvement of this receptor network in the metabolic programming of macrophages and dendritic cells (DCs), essential members of the innate immune system. In this review we focus on the role of retinoid X receptor, retinoic acid receptor, peroxisome proliferator-associated receptor γ, liver X receptor, and vitamin D receptor in shaping the immune and metabolic functions of macrophages and DCs. We also provide an overview of the contribution of macrophage- and DC-expressed nuclear receptors to various immunopathologic conditions, such as rheumatoid arthritis, inflammatory bowel disease, systemic lupus erythematosus, asthma, and some others. We suggest that systematic analyses of the roles of these receptors and their activating lipid ligands in immunopathologies combined with complementary and focused translational and clinical research will be crucial for the development of new therapies using the many molecules available to target nuclear receptors.
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Affiliation(s)
- Mate Kiss
- Department of Biochemistry and Molecular Biology, Research Center for Molecular Medicine, University of Debrecen, Medical and Health Science Center, Debrecen, Hungary
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71
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Abstract
Alzheimer’s disease (AD) is complicated and difficult to fully understand, it might need multiple drug-discovery strategies to combat the disease. Regardless of the cause of AD, neuronal death in the brain plays a key role in AD progression and is directly linked to neuroinflammation. Thus, the regulation of neuroinflammatory processes might be a practical strategy for the treatment of AD. This review highlights the development of anti-neuroinflammatory agents that have shown promise in vitro or in vivo by attenuating microglial activation or cognitive decline. The agents are categorized based on the related signaling pathways, including the receptor for advanced glycation end products, p38 MAPKs, NF-κB and peroxisome proliferator-activated receptor γ; and inhibitors against microglial activation lacking clear mechanisms. These anti-neuroinflammatory agents support the concept and represent important chemical probes for the development of anti-neuroinflammatory drugs for the treatment of AD.
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72
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McCarthy FP, Delany AC, Kenny LC, Walsh SK. PPAR-γ -- a possible drug target for complicated pregnancies. Br J Pharmacol 2013. [PMID: 23186152 DOI: 10.1111/bph.12069] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Peroxisome proliferator activated receptors (PPARs) are ligand-activated transcription factors expressed in trophoblasts, which regulate both cell differentiation and proliferation. In recent years, evidence has linked PPARs to playing an integral role in pregnancy; specifically, PPAR-β and PPAR-γ have been shown to play an integral role in placentation, with PPAR-γ additionally serving to regulate trophoblast differentiation. Recent evidence has shown that PPAR-γ expression is altered in many complications of pregnancy such as intrauterine growth restriction (IUGR), preterm birth, pre-clampsia and gestational diabetes. Thus, at present, accumulating evidence from the literature suggests both a pivotal role for PPAR-γ in the progression of a healthy pregnancy and the possibility that PPAR-γ may act as a therapeutic target in complicated pregnancies. This review aims to provide a succinct and comprehensive assessment of the role of PPAR-γ in normal pregnancy and pregnancy complications, and finally its potential as a therapeutic target in the treatment and/or prevention of adverse pregnancy outcomes.
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Affiliation(s)
- Fergus P McCarthy
- Department of Obstetrics & Gynaecology, Anu Research Centre, University College Cork, Cork, Ireland
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73
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Sodhi RK, Singh N. Defensive effect of lansoprazole in dementia of AD type in mice exposed to streptozotocin and cholesterol enriched diet. PLoS One 2013; 8:e70487. [PMID: 23936214 PMCID: PMC3729942 DOI: 10.1371/journal.pone.0070487] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 06/19/2013] [Indexed: 11/28/2022] Open
Abstract
The present study investigates the potential of lansoprazole (a proton pump inhibitor and agonist of liver x receptors) in experimental dementia of AD type. Streptozotocin [STZ, 3 mg/kg, injected intracerebroventricular (i.c.v), and high fat diet (HFD, administered for 90 days)] were used to induce dementia in separate groups of Swiss mice. Morris water maze (MWM) test was performed to assess learning and memory of the animals. A battery of biochemical and histopathological studies were also performed. Extent of oxidative stress was measured by estimating the levels of brain reduced glutathione (GSH) and thiobarbituric acid reactive species (TBARS). Brain acetylcholinestrase (AChE) activity and serum cholesterol levels were also estimated. The brain level of myeloperoxidase (MPO) was measured as a marker of inflammation. STZ and HFD produced a marked decline in MWM performance of the animals, reflecting impairment of learning and memory. STZ/HFD treated mice exhibited a marked accentuation of AChE activity, TBARS and MPO levels along with a fall in GSH levels. Further, the stained micrographs of STZ/HFD treated mice indicated pathological changes, severe neutrophilic infiltration and amyloid deposition. Lansoprazole treatment significantly attenuated STZ and HFD -induced memory deficits, biochemical and histopathological alterations. It also prevented HFD-induced rise in the cholesterol level. Therefore, the findings demonstrate potential of lansoprazole in memory dysfunctions which may probably be attributed to its anti-cholinesterase, anti-oxidative and anti-inflammatory effects. Moreover, both cholesterol-dependent as well as cholesterol-independent effects of lansoprazole appear to play a role. In addition study indicates the role of liver x receptors in dementia.
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Affiliation(s)
- Rupinder K. Sodhi
- Pharmacology Division, Department of Pharmaceutical Sciences and Drug Research, Faculty of Medicine, Punjabi University, Punjab, India
| | - Nirmal Singh
- Pharmacology Division, Department of Pharmaceutical Sciences and Drug Research, Faculty of Medicine, Punjabi University, Punjab, India
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74
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Abstract
Receptor-based targeting of therapeutics may be a fascinating proposition to improve the therapeutic efficacy of encapsulated drugs. The development of safe and effective nanomedicines is a prerequisite in the current nanotechnological scenario. Currently, the surface engineering of nanocarriers has attracted great attention for targeted therapeutic delivery by selective binding of targeting ligand to the specific receptors present on the surface of cells. In this review, we have discussed the current status of various receptors such as transferrin, lectoferrin, lectin, folate, human EGF receptor, scavenger, nuclear and integrin, which are over-expressed on the surface of cancer cells; along with the relevance of targeted delivery systems such as nanoparticles, polymersomes, dendrimers, liposomes and carbon nanotubes. The review also focuses on the effective utilization of receptor-based targeted delivery systems for the management of cancer in effective ways by minimizing the drug-associated side effects and improving the therapeutic efficacy of developed nano-architectures.
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75
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Role of nuclear receptors in the regulation of drug transporters in the brain. Trends Pharmacol Sci 2013; 34:361-72. [PMID: 23769624 DOI: 10.1016/j.tips.2013.05.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 04/24/2013] [Accepted: 05/08/2013] [Indexed: 02/07/2023]
Abstract
ATP-binding cassette membrane-associated drug efflux transporters and solute carrier influx transporters, expressed at the blood-brain barrier, blood-cerebrospinal fluid barrier, and in brain parenchyma, are important determinants of drug disposition in the central nervous system. Targeting the regulatory pathways that govern the expression of these transporters could provide novel approaches to selectively alter drug permeability into the brain. Nuclear receptors are ligand-activated transcription factors which regulate the gene expression of several metabolic enzymes and drug efflux/influx transporters. Although efforts have primarily been focused on investigating these regulatory pathways in peripheral organs (i.e., liver and intestine), recent findings demonstrate their significance in the brain. This review addresses the role of nuclear receptors in the regulation of drug transporter functional expression in the brain. An in-depth understanding of these pathways could guide the development of novel pharmacotherapy with either enhanced efficacy in the central nervous system or minimal associated neurotoxicity.
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76
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Price AR, Xu G, Siemienski ZB, Smithson LA, Borchelt DR, Golde TE, Felsenstein KM. Comment on "ApoE-directed therapeutics rapidly clear β-amyloid and reverse deficits in AD mouse models". Science 2013; 340:924-d. [PMID: 23704553 DOI: 10.1126/science.1234089] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cramer et al. (Reports, 23 March 2012, p. 1503; published online 9 February 2012) demonstrates short-term bexarotene treatment clearing preexisting β-amyloid deposits from the brains of APP/PS1ΔE9 mice with low amyloid burden, providing a rationale for repurposing this anticancer agent as an Alzheimer's disease (AD) therapeutic. Using a nearly identical treatment regimen, we were unable to detect any evidence of drug efficacy despite demonstration of target engagement.
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Affiliation(s)
- Ashleigh R Price
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, University of Florida College of Medicine, 1275 Center Drive, Gainesville, FL 32610, USA
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Landreth GE, Cramer PE, Lakner MM, Cirrito JR, Wesson DW, Brunden KR, Wilson DA. Response to comments on "ApoE-directed therapeutics rapidly clear β-amyloid and reverse deficits in AD mouse models". Science 2013; 340:924-g. [PMID: 23704556 DOI: 10.1126/science.1234114] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The data reported in the Technical Comments by Fitz et al., Price et al., Tesseur et al., and Veeraraghavalu et al. replicate and validate our central conclusion that bexarotene stimulates the clearance of soluble β-amyloid peptides and results in the reversal of behavioral deficits in mouse models of Alzheimer's disease (AD). The basis of the inability to reproduce the drug-stimulated microglial-mediated reduction in plaque burden is unexplained. However, we concluded that plaque burden is functionally unrelated to improved cognition and memory elicited by bexarotene.
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Affiliation(s)
- Gary E Landreth
- Alzheimer Research Laboratory, Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA.
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78
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Golde TE, Streit WJ, Chakrabarty P. Alzheimer's disease risk alleles in TREM2 illuminate innate immunity in Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2013; 5:24. [PMID: 23692967 PMCID: PMC3706774 DOI: 10.1186/alzrt178] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Genetic studies have provided the best evidence for cause and effect relationships in Alzheimer's disease (AD). Indeed, the identification of deterministic mutations in the APP, PSEN1 and PSEN2 genes and subsequent preclinical studies linking these mutations to alterations in Aβ production and aggregation have provided pivotal support for the amyloid cascade hypothesis. In addition, genetic, pathologic and biological studies of APOE have also indicated that the genetic risk for AD associated with APOE4 can be attributed, at least in part, to its pro-amyloidogenic effect on Aβ. In recent years a number of SNPs that show unequivocal genome-wide association with AD risk have implicated novel genetic loci as modifiers of AD risk. However, the functional implications of these genetic associations are largely unknown. For almost all of these associations, the functional variants have not been identified. Very recently, two large consortiums demonstrated that rare variants in the triggering receptor expressed on myeloid cells 2 (TREM2) gene confer significant risk for AD. TREM2 is a type 1 membrane receptor protein primarily expressed on microglia in the central nervous system that has been shown to regulate phagocytosis and activation of monocytes. Previously it had been shown that homozygous loss of function mutations in TREM2 cause polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL, Nasu Hakola disease) and also a pure form of early-onset dementia. The association of TREM2 variants with AD brings innate immune signaling into the light, affirming innate immunity's role as a significant factor in AD pathogenesis.
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Affiliation(s)
- Todd E Golde
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Wolfgang J Streit
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Paramita Chakrabarty
- Center for Translational Research in Neurodegenerative Disease, Department of Neuroscience, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
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79
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Pioglitazone ameliorates memory deficits in streptozotocin-induced diabetic mice by reducing brain β-amyloid through PPARγ activation. Acta Pharmacol Sin 2013; 34:455-63. [PMID: 23524568 DOI: 10.1038/aps.2013.11] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
AIM To examine the effects of pioglitazone, a PPARγ agonist, on memory performance and brain amyloidogenesis in streptozotocin (STZ)-induced diabetic mice. METHODS ICR male mice were injected with STZ (150 mg/kg, iv) to induce experimental diabetes. Pioglitazone (9 and 18 mg·kg(-1)·d(-1), po) was administered for 6 weeks. Passive avoidance and Morris water maze (MWM) tests were used to evaluate cognitive function. The blood glucose and serum insulin levels were detected using the glucose oxidase method and an ELISA assay, respectively. β-amyloid (Aβ), β-amyloid precursor protein (APP), β-amyloid precursor protein cleaving enzyme 1 (BACE1), NF-κB p65, the receptor for advanced glycation end products (RAGE) and PPARγ in the brains were analyzed using Western blotting assays. RESULTS The STZ-induced diabetic mice characterized by hyperglycemia and hypoinsulinemia performed poorly in both the passive avoidance and MWM tests, accompanied by increased Aβ1-40/Aβ1-42, APP, BACE1, NF-κB p65 and RAGE levels and decreased PPARγ level in the hippocampus and cortex. Chronic pioglitazone treatment significantly ameliorated the memory deficits and amyloidogenesis of STZ-induced diabetic mice, and suppressed expression of APP, BACE1, RAGE and NF-κB p65, and activated PPARγ in the hippocampus and cortex. However, pioglitazone did not significantly affect blood glucose and insulin levels. CONCLUSION Pioglitazone ameliorates memory deficits in STZ-induced diabetic mice by reducing brain Aβ level via activation of PPARγ, which is independent of its effects on blood glucose and insulin levels. The results suggest that pioglitazone may be used for treating the cognitive dysfunction in type 1 diabetes mellitus.
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80
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Sodhi RK, Singh N. Liver X receptors: emerging therapeutic targets for Alzheimer's disease. Pharmacol Res 2013; 72:45-51. [PMID: 23542729 DOI: 10.1016/j.phrs.2013.03.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 03/11/2013] [Accepted: 03/21/2013] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disorder, typified by the pathological accumulation of ß-amyloid peptides (Aß) and neurofibrillary tangles within the brain, culminating to cognitive impairment. Epidemiological and biochemical data have suggested a link between cholesterol content, APP (amyloid precursor protein) processing, Aß, inflammation and AD. The intricacy of the disease presents considerable challenges for the development of newer therapeutic agents. Liver X receptors (LXRa and LXRß) are oxysterol activated nuclear receptors that play essential role in lipid and glucose homeostasis, steroidogenesis and inflammatory responses. LXR signalling impacts the development of AD pathology through multiple pathways. Reports indicate that genetic loss of either lxra or lxrß in APP/PS1 transgenic mice results in increased amyloid plaque load. Studies also suggest that ligand activation of LXRs in Tg2576 mice enhanced, the expression of genes linked with cholesterol efflux e.g. apoe, abca-1, down regulated APP processing and Aß production with significant improvement in memory functions. LXR agonists have also depicted to inhibit neuroinflammation through modulation of microglial phagocytosis and by repressing the expression of cox2, mcp1 and iNos in glial cells. This review summarizes in brief the biology of LXRs, with an emphasis on their probable pathophysiological mechanisms that may elicit the defending role of these receptors in brains of AD patients.
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Affiliation(s)
- Rupinder K Sodhi
- Pharmacology Division, Department of Pharmaceutical Sciences and Drug Research, Faculty of Medicine, Punjabi University, Patiala 147002, Punjab, India
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81
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Peroxisome proliferator-activated receptors and Alzheimer's disease: hitting the blood-brain barrier. Mol Neurobiol 2013; 48:438-51. [PMID: 23494748 DOI: 10.1007/s12035-013-8435-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 02/26/2013] [Indexed: 01/20/2023]
Abstract
The blood-brain barrier (BBB) is often affected in several neurodegenerative disorders, such as Alzheimer's disease (AD). Integrity and proper functionality of the neurovascular unit are recognized to be critical for maintenance of the BBB. Research has traditionally focused on structural integrity more than functionality, and BBB alteration has usually been explained more as a consequence than a cause. However, ongoing evidence suggests that at the early stages, the BBB of a diseased brain often shows distinct expression patterns of specific carriers such as members of the ATP-binding cassette (ABC) transport protein family, which alter BBB traffic. In AD, amyloid-β (Aβ) deposits are a pathological hallmark and, as recently highlighted by Cramer et al. (2012), Aβ clearance is quite fundamental and is a less studied approach. Current knowledge suggests that BBB traffic plays a more important role than previously believed and that pharmacological modulation of the BBB may offer new therapeutic alternatives for AD. Recent investigations carried out in our laboratory indicate that peroxisome proliferator-activated receptor (PPAR) agonists are able to prevent Aβ-induced neurotoxicity in hippocampal neurons and cognitive impairment in a double transgenic mouse model of AD. However, even when enough literature about PPAR agonists and neurodegenerative disorders is available, the problem of how they exert their functions and help to prevent and rescue Aβ-induced neurotoxicity is poorly understood. In this review, along with highlighting the main features of the BBB and its role in AD, we will discuss information regarding the modulation of BBB components, including the possible role of PPAR agonists as BBB traffic modulators.
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Abstract
Microglia are resident immune cells in the brain and spinal cord. These cells provide immune surveillance and are mobilized in response to disparate diseases and injuries. Although microglial activation is often considered neurotoxic, microglia are essential defenders against many neurodegenerative diseases. It also seems increasingly likely that microglial dysfunction can underlie certain neurological diseases without an obvious immune component.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zurich, Schmelzbergstrasse 12, CH-8012 Zurich, Switzerland.
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83
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Panlilio LV, Justinova Z, Goldberg SR. Inhibition of FAAH and activation of PPAR: new approaches to the treatment of cognitive dysfunction and drug addiction. Pharmacol Ther 2013; 138:84-102. [PMID: 23333350 DOI: 10.1016/j.pharmthera.2013.01.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 12/21/2012] [Indexed: 12/16/2022]
Abstract
Enhancing the effects of endogenously-released cannabinoid ligands in the brain might provide therapeutic effects more safely and effectively than administering drugs that act directly at the cannabinoid receptor. Inhibitors of fatty acid amide hydrolase (FAAH) prevent the breakdown of endogenous ligands for cannabinoid receptors and peroxisome proliferator-activated receptors (PPAR), prolonging and enhancing the effects of these ligands when they are naturally released. This review considers recent research on the effects of FAAH inhibitors and PPAR activators in animal models of addiction and cognition (specifically learning and memory). These studies show that FAAH inhibitors can produce potentially therapeutic effects, some through cannabinoid receptors and some through PPAR. These effects include enhancing certain forms of learning, counteracting the rewarding effects of nicotine and alcohol, relieving symptoms of withdrawal from cannabis and other drugs, and protecting against relapse-like reinstatement of drug self-administration. Since FAAH inhibition might have a wide range of therapeutic actions but might also share some of the adverse effects of cannabis, it is noteworthy that at least one FAAH-inhibiting drug (URB597) has been found to have potentially beneficial effects but no indication of liability for abuse or dependence. Although these areas of research are new, the preliminary evidence indicates that they might lead to improved therapeutic interventions and a better understanding of the brain mechanisms underlying addiction and memory.
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Affiliation(s)
- Leigh V Panlilio
- Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, MD 21224, USA
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Yang J, Li S, Liu YX. Systematic analysis of diabetes- and glucose metabolism-related proteins and its application to Alzheimer’s disease. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/jbise.2013.66078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Dumont M, Stack C, Elipenahli C, Jainuddin S, Gerges M, Starkova N, Calingasan NY, Yang L, Tampellini D, Starkov AA, Chan RB, Di Paolo G, Pujol A, Beal MF. Bezafibrate administration improves behavioral deficits and tau pathology in P301S mice. Hum Mol Genet 2012; 21:5091-105. [PMID: 22922230 PMCID: PMC3490516 DOI: 10.1093/hmg/dds355] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 08/17/2012] [Indexed: 12/11/2022] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) are ligand-mediated transcription factors, which control both lipid and energy metabolism and inflammation pathways. PPARγ agonists are effective in the treatment of metabolic diseases and, more recently, neurodegenerative diseases, in which they show promising neuroprotective effects. We studied the effects of the pan-PPAR agonist bezafibrate on tau pathology, inflammation, lipid metabolism and behavior in transgenic mice with the P301S human tau mutation, which causes familial frontotemporal lobar degeneration. Bezafibrate treatment significantly decreased tau hyperphosphorylation using AT8 staining and the number of MC1-positive neurons. Bezafibrate treatment also diminished microglial activation and expression of both inducible nitric oxide synthase and cyclooxygenase 2. Additionally, the drug differentially affected the brain and brown fat lipidome of control and P301S mice, preventing lipid vacuoles in brown fat. These effects were associated with behavioral improvement, as evidenced by reduced hyperactivity and disinhibition in the P301S mice. Bezafibrate therefore exerts neuroprotective effects in a mouse model of tauopathy, as shown by decreased tau pathology and behavioral improvement. Since bezafibrate was given to the mice before tau pathology had developed, our data suggest that bezafibrate exerts a preventive effect on both tau pathology and its behavioral consequences. Bezafibrate is therefore a promising agent for the treatment of neurodegenerative diseases associated with tau pathology.
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Affiliation(s)
- Magali Dumont
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, NY 10065, USA.
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Mechanisms underlying the rapid peroxisome proliferator-activated receptor-γ-mediated amyloid clearance and reversal of cognitive deficits in a murine model of Alzheimer's disease. J Neurosci 2012; 32:10117-28. [PMID: 22836247 DOI: 10.1523/jneurosci.5268-11.2012] [Citation(s) in RCA: 275] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Alzheimer's disease is associated with a disruption of amyloid β (Aβ) homeostasis, resulting in the accumulation and subsequent deposition of Aβ peptides within the brain. The peroxisome proliferator-activated receptor-γ (PPARγ) is a ligand-activated nuclear receptor that acts in a coupled metabolic cycle with Liver X Receptors (LXRs) to increase brain apolipoprotein E (apoE) levels. apoE functions to promote the proteolytic clearance of soluble forms of Aβ, and we found that the synthetic PPARγ agonist, pioglitazone, stimulated Aβ degradation by both microglia and astrocytes in an LXR and apoE-dependent manner. Remarkably, a brief 9 d oral treatment of APPswe/PS1Δe9 mice with pioglitazone resulted in dramatic reductions in brain levels of soluble and insoluble Aβ levels which correlated with the loss of both diffuse and dense-core plaques within the cortex. The removal of preexisting amyloid deposits was associated with the appearance of abundant Aβ-laden microglia and astrocytes. Pioglitazone treatment resulted in the phenotypic polarization of microglial cells from a proinflammatory M1 state, into an anti-inflammatory M2 state that was associated with enhanced phagocytosis of deposited forms of amyloid. The reduction in amyloid levels was associated with a reversal of contextual memory deficits in the drug-treated mice. These data provide a mechanistic explanation for how PPARγ activation facilitates amyloid clearance and supports the therapeutic utility of PPARγ agonists for the treatment of Alzheimer's disease.
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Bellavance MA, Rivest S. The neuroendocrine control of the innate immune system in health and brain diseases. Immunol Rev 2012; 248:36-55. [PMID: 22725953 DOI: 10.1111/j.1600-065x.2012.01129.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The innate immune reaction takes place in the brain during immunogenic challenges, injury, and disease. Such a response is highly regulated by numerous anti-inflammatory mechanisms that may directly affect the ultimate consequences of such a reaction within the cerebral environment. The neuroendocrine control of this innate immune system by glucocorticoids is critical for the delicate balance between cell survival and damage in the presence of inflammatory mediators. Glucocorticoids play key roles in regulating the expression of inflammatory genes, and they also have the ability to modulate numerous functions that may ultimately lead to brain damage or repair after injury. Here we review these mechanisms and discuss data supporting both neuroprotective and detrimental roles of the neuroendocrine control of innate immunity.
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Affiliation(s)
- Marc-André Bellavance
- Laboratory of Endocrinology and Genomics, CHUQ Research Center and Department of Molecular Medicine, Faculty of Medicine, Laval University, Québec, Canada
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88
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Hawk JD, Bookout AL, Poplawski SG, Bridi M, Rao AJ, Sulewski ME, Kroener BT, Manglesdorf DJ, Abel T. NR4A nuclear receptors support memory enhancement by histone deacetylase inhibitors. J Clin Invest 2012; 122:3593-602. [PMID: 22996661 DOI: 10.1172/jci64145] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 07/26/2012] [Indexed: 02/06/2023] Open
Abstract
The formation of a long-lasting memory requires a transcription-dependent consolidation period that converts a short-term memory into a long-term memory. Nuclear receptors compose a class of transcription factors that regulate diverse biological processes, and several nuclear receptors have been implicated in memory formation. Here, we examined the potential contribution of nuclear receptors to memory consolidation by measuring the expression of all 49 murine nuclear receptors after learning. We identified 13 nuclear receptors with increased expression after learning, including all 3 members of the Nr4a subfamily. These CREB-regulated Nr4a genes encode ligand-independent "orphan" nuclear receptors. We found that blocking NR4A activity in memory-supporting brain regions impaired long-term memory but did not impact short-term memory in mice. Further, expression of Nr4a genes increased following the memory-enhancing effects of histone deacetylase (HDAC) inhibitors. Blocking NR4A signaling interfered with the ability of HDAC inhibitors to enhance memory. These results demonstrate that the Nr4a gene family contributes to memory formation and is a promising target for improving cognitive function.
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Affiliation(s)
- Joshua D Hawk
- Neuroscience Graduate Group and Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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89
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90
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Johri A, Beal MF. Mitochondrial dysfunction in neurodegenerative diseases. J Pharmacol Exp Ther 2012; 342:619-30. [PMID: 22700435 DOI: 10.1124/jpet.112.192138] [Citation(s) in RCA: 473] [Impact Index Per Article: 39.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Neurodegenerative diseases are a large group of disabling disorders of the nervous system, characterized by the relative selective death of neuronal subtypes. In most cases, there is overwhelming evidence of impaired mitochondrial function as a causative factor in these diseases. More recently, evidence has emerged for impaired mitochondrial dynamics (shape, size, fission-fusion, distribution, movement etc.) in neurodegenerative diseases such as Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and Alzheimer's disease. Here, we provide a concise overview of the major findings in recent years highlighting the importance of healthy mitochondria for a healthy neuron.
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Affiliation(s)
- Ashu Johri
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY, USA
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91
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Jiang LY, Tang SS, Wang XY, Liu LP, Long Y, Hu M, Liao MX, Ding QL, Hu W, Li JC, Hong H. PPARγ agonist pioglitazone reverses memory impairment and biochemical changes in a mouse model of type 2 diabetes mellitus. CNS Neurosci Ther 2012; 18:659-66. [PMID: 22620268 DOI: 10.1111/j.1755-5949.2012.00341.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
AIMS Pioglitazone, known as a peroxisome proliferator-activated receptor γ (PPARγ) agonist, is used to treat type 2 diabetes mellitus (T2DM). T2DM has been associated with reduced performance on numerous domains of cognitive function. Here, we investigated the effects of pioglitazone on memory impairment in a mouse model with defects in insulin sensitivity and secretion, namely high-fat diet (HFD) streptozotocin (STZ)-induced diabetic mice. METHODS ICR mice were fed with HFD for 4 weeks and then injected with a single low dose of STZ followed by continued HFD feeding for an additional 4 weeks. Pioglitazone (18 mg/kg, 9 mg/kg body weight) was orally administered for 6 weeks once daily. Y-maze test and Morris water maze test (MWM) were employed for testing learning and memory. Serum glucose, serum insulin, serum triglyceride, brain β-amyloid peptide (Aβ), brain β-site amyloid precursor protein cleaving enzyme (BACE1), brain nuclear factor κB (NF-κB), and brain receptor for advanced glycation end products (RAGE) were also tested. RESULTS The STZ/HFD diabetic mice, characterized by hyperglycemia, hyperlipemia and hypoinsulinemia, performed poorly on Y-maze and MWM hence reflecting impairment of learning and memory behavior with increases of Aβ40/Aβ42, BACE1, NF-κB, and RAGE in brain. Treatment of PPARγ agonist, pioglitazone (18 or 9 mg/kg body weight), significantly reversed diabetes-induced impairment of learning and memory behavior, which is involved in decreases of Aβ40/Aβ42 via inhibition of NF-κB, BACE1 and RAGE in brain as well as attenuation of hyperglycemia, hyperlipemia, and hypoinsulinemia. CONCLUSIONS It is concluded that PPARγ agonist pioglitazone may be considered as potential pharmacological agents for the management of cognitive dysfunction in T2DM.
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Affiliation(s)
- Li-Ying Jiang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China Department of Pharmacy, the Second Hospital Affiliated to Anhui Medical University, Hefei, China
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92
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Xiang GQ, Tang SS, Jiang LY, Hong H, Li Q, Wang C, Wang XY, Zhang TT, Yin L. PPARγ agonist pioglitazone improves scopolamine-induced memory impairment in mice. J Pharm Pharmacol 2012; 64:589-96. [DOI: 10.1111/j.2042-7158.2011.01432.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Abstract
Objectives
This study was conducted to evaluate the effects of exposure to pioglitazone, a peroxisome proliferator-activated receptor agonist, on cognitive impairment induced by scopolamine, a muscarinic antagonist, in mice.
Methods
Pioglitazone (9 mg/kg, 18 mg/kg) was orally administered for 9 days at 30 min before intraperitoneal injection with scopolamine (0.8 mg/kg, i.p.). Cognitive function was evaluated by the passive avoidance test and the Morris water maze test on the 10th day after treatment. Changes in cholinergic system reactivity were also examined by measuring the acetylcholine, acetylcholinesterase and choline acetyltransferase in the hippocampus and cortex.
Key findings
Scopolamine injection induced impaired performance in the passive avoidance test and the water maze test and severe decrease of cholinergic system reactivity, as indicated by reduced acetylcholine levels, decreased choline acetyltransferase activity and increased acetylcholinesterase activity. Daily administration of pioglitazone significantly increased step-through latency in passive avoidance test, and significantly decreased the escape latency, and increased the time spent in the platform quadrant in the Morris water maze test. Pioglitazone also protected against scopolamine-induced cholinergic system deficit, including reduced acetylcholine levels, decreased choline acetyltransferase activity and increased acetylcholinesterase activity in the hippocampus or cortex.
Conclusions
Pioglitazone demonstrates a significant neuroprotective effect against scopolamine-induced cholinergic system deficit and cognitive impairment.
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Affiliation(s)
- Guo Qing Xiang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Su Su Tang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Li Ying Jiang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Hao Hong
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Qing Li
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Chao Wang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Xiao Yun Wang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Ting Ting Zhang
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
| | - Lei Yin
- Department of Pharmacology, China Pharmaceutical University, Nanjing, China
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Cramer PE, Cirrito JR, Wesson DW, Lee CYD, Karlo JC, Zinn AE, Casali BT, Restivo JL, Goebel WD, James MJ, Brunden KR, Wilson DA, Landreth GE. ApoE-directed therapeutics rapidly clear β-amyloid and reverse deficits in AD mouse models. Science 2012; 335:1503-6. [PMID: 22323736 DOI: 10.1126/science.1217697] [Citation(s) in RCA: 809] [Impact Index Per Article: 67.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Alzheimer's disease (AD) is associated with impaired clearance of β-amyloid (Aβ) from the brain, a process normally facilitated by apolipoprotein E (apoE). ApoE expression is transcriptionally induced through the action of the nuclear receptors peroxisome proliferator-activated receptor gamma and liver X receptors in coordination with retinoid X receptors (RXRs). Oral administration of the RXR agonist bexarotene to a mouse model of AD resulted in enhanced clearance of soluble Aβ within hours in an apoE-dependent manner. Aβ plaque area was reduced more than 50% within just 72 hours. Furthermore, bexarotene stimulated the rapid reversal of cognitive, social, and olfactory deficits and improved neural circuit function. Thus, RXR activation stimulates physiological Aβ clearance mechanisms, resulting in the rapid reversal of a broad range of Aβ-induced deficits.
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Affiliation(s)
- Paige E Cramer
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
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