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Zaichick S, Caraveo G. Harnessing IGF-1 and IL-2 as biomarkers for calcineurin activity to tailor optimal FK506 dosage in α-synucleinopathies. Front Mol Biosci 2023; 10:1292555. [PMID: 38094080 PMCID: PMC10716490 DOI: 10.3389/fmolb.2023.1292555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 11/16/2023] [Indexed: 02/01/2024] Open
Abstract
Introduction: Rise in Calcium (Ca2+) and hyperactive Ca2+-dependent phosphatase calcineurin represent two key determinants of a-synuclein (a-syn) pathobiology implicated in Parkinson's Disease (PD) and other neurodegenerative diseases. Calcineurin activity can be inhibited with FK506, a Food and Drug Administration (FDA)-approved compound. Our previous work demonstrated a protective effect of low doses of FK506 against a-syn pathology in various models of a-syn related pathobiology. Methods: Control and a-syn-expressing mice (12-18 months old) were injected with vehicle or two single doses of FK506 administered 4 days apart. Cerebral cortex and serum from these mice were collected and assayed using a meso scale discovery quickplex SQ 120 for cytokines and Enzyme-linked immunosorbent assay for IGF-1. Results: In this study we present evidence that reducing calcineurin activity with FK506 in a-syn transgenic mice increased insulin growth factor (IGF-1), while simultaneously decreasing IL-2 levels in both cerebral cortex and serum. Discussion: The highly conserved Ca2+/calcineurin signaling pathway is known to be affected in a-syn-dependent human disease. FK506, an already approved drug for other uses, exhibits high brain penetrance and a proven safety profile. IL-2 and IGF-1 are produced throughout life and can be measured using standard clinical methods. Our findings provide two potential biomarkers that could guide a clinical trial of FK506 in PD patients, without posing significant logistical or regulatory challenges.
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Affiliation(s)
| | - Gabriela Caraveo
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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Smith MJ, Penny T, Pham Y, Sutherland AE, Jenkin G, Fahey MC, Paton MCB, Finch-Edmondson M, Miller SL, McDonald CA. Neuroprotective Action of Tacrolimus before and after Onset of Neonatal Hypoxic-Ischaemic Brain Injury in Rats. Cells 2023; 12:2659. [PMID: 37998394 PMCID: PMC10669941 DOI: 10.3390/cells12222659] [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: 10/10/2023] [Revised: 11/14/2023] [Accepted: 11/15/2023] [Indexed: 11/25/2023] Open
Abstract
(1) Background: Neonatal brain injury can lead to permanent neurodevelopmental impairments. Notably, suppressing inflammatory pathways may reduce damage. To determine the role of neuroinflammation in the progression of neonatal brain injury, we investigated the effect of treating neonatal rat pups with the immunosuppressant tacrolimus at two time points: before and after hypoxic-ischaemic (HI)-induced injury. (2) Methods: To induce HI injury, postnatal day (PND) 10 rat pups underwent single carotid artery ligation followed by hypoxia (8% oxygen, 90 min). Pups received daily tacrolimus (or a vehicle) starting either 3 days before HI on PND 7 (pre-HI), or 12 h after HI (post-HI). Four doses were tested: 0.025, 0.05, 0.1 or 0.25 mg/kg/day. Pups were euthanised at PND 17 or PND 50. (3) Results: All tacrolimus doses administered pre-HI significantly reduced brain infarct size and neuronal loss, increased the number of resting microglia and reduced cellular apoptosis (p < 0.05 compared to control). In contrast, only the highest dose of tacrolimus administered post-HI (0.25 mg/kg/day) reduced brain infarct size (p < 0.05). All doses of tacrolimus reduced pup weight compared to the controls. (4) Conclusions: Tacrolimus administration 3 days pre-HI was neuroprotective, likely mediated through neuroinflammatory and cell death pathways. Tacrolimus post-HI may have limited capacity to reduce brain injury, with higher doses increasing rat pup mortality. This work highlights the benefits of targeting neuroinflammation during the acute injurious period. More specific targeting of neuroinflammation, e.g., via T-cells, warrants further investigation.
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Affiliation(s)
- Madeleine J. Smith
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC 3168, Australia
| | - Tayla Penny
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
| | - Yen Pham
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
| | - Amy E. Sutherland
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
| | - Graham Jenkin
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC 3168, Australia
| | - Michael C. Fahey
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
- Department of Paediatrics, Monash University, Clayton, VIC 3168, Australia
| | - Madison C. B. Paton
- Cerebral Palsy Alliance Research Institute, Speciality of Child and Adolescent Health, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia; (M.C.B.P.); (M.F.-E.)
| | - Megan Finch-Edmondson
- Cerebral Palsy Alliance Research Institute, Speciality of Child and Adolescent Health, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2050, Australia; (M.C.B.P.); (M.F.-E.)
| | - Suzanne L. Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC 3168, Australia
| | - Courtney A. McDonald
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia; (M.J.S.); (T.P.); (Y.P.); (A.E.S.); (G.J.); (M.C.F.); (S.L.M.)
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC 3168, Australia
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Araújo NC, Suassuna JHR, Fernandes RDCL. Transcranial sonography depicts a larger substantia nigra echogenic area in renal transplant patients on calcineurin inhibitors than on rapamycin. BMC Nephrol 2022; 23:108. [PMID: 35300603 PMCID: PMC8931960 DOI: 10.1186/s12882-022-02741-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 03/14/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND After kidney transplantation neurologic manifestations may develop, including Parkinson's disease (PD). An enlarged substantia nigra (SN) by transcranial sonography has been recognized as a marker of PD. METHODS In renal transplant recipients (RTRs = 95) and controls (n = 20), measurement of mesencephalon, SN, third ventricle, spleen and carotid intima-media thickness (cIMT) and middle cerebral artery (MCA), kidney and spleen arteries Doppler resistive index (RI) were performed. RESULTS RTRs had larger SN, third ventricle and cIMT and higher renal RI than controls. The SN was larger in the CNIs group than in controls and rapamycin group, while the third ventricle was similar between patients but larger than in controls. In RTRs, SN showed a direct linear correlation with spleen and the third ventricle with age, cIMT and RI of the MCA, kidney and spleen. In CNIs group the SN correlated positively with age and cIMT, while the third ventricle reproduced RTRs correlations. Rapamycin group showed a direct linear relationship between the third ventricle and age and RI of the MCA, kidney and spleen; SN showed no correlations. CONCLUSION RTRs on CNIs present a larger SN area than on rapamycin, probably due to the antiproliferative effect of rapamycin. This finding might be relevant when interpreting TCS in RTRs.
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Affiliation(s)
- Nordeval Cavalcante Araújo
- Division of Nephrology, University of the State of Rio de Janeiro, Boulevard 28 de Setembro, 77 - Vila Isabel, Rio de Janeiro-RJ, 20551-030, Brazil.
| | - José Hermógenes Rocco Suassuna
- Division of Nephrology, University of the State of Rio de Janeiro, Boulevard 28 de Setembro, 77 - Vila Isabel, Rio de Janeiro-RJ, 20551-030, Brazil
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Hu Z, Gajavelli S, Spurlock MS, Mahavadi A, Quesada LS, Gajavelli GR, Andreoni CB, Di L, Janecki J, Lee SW, Rivera KN, Shear DA, Bullock RM. Human neural stem cell transplant location-dependent neuroprotection and motor deficit amelioration in rats with penetrating traumatic brain injury. J Trauma Acute Care Surg 2020; 88:477-485. [PMID: 31626023 PMCID: PMC7098436 DOI: 10.1097/ta.0000000000002510] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 08/30/2019] [Accepted: 09/17/2019] [Indexed: 11/26/2022]
Abstract
BACKGROUND Penetrating traumatic brain injury induces chronic inflammation that drives persistent tissue loss long after injury. Absence of endogenous reparative neurogenesis and effective neuroprotective therapies render injury-induced disability an unmet need. Cell replacement via neural stem cell transplantation could potentially rebuild the tissue and alleviate penetrating traumatic brain injury disability. The optimal transplant location remains to be determined. METHODS To test if subacute human neural stem cell (hNSC) transplant location influences engraftment, lesion expansion, and motor deficits, rats (n = 10/group) were randomized to the following four groups (uninjured and three injured): group 1 (Gr1), uninjured with cell transplants (sham+hNSCs), 1-week postunilateral penetrating traumatic brain injury, after establishing motor deficit; group 2 (Gr2), treated with vehicle (media, no cells); group 3 (Gr3), hNSCs transplanted into lesion core (intra); and group 4 (Gr4), hNSCs transplanted into tissue surrounding the lesion (peri). All animals were immunosuppressed for 12 weeks and euthanized following motor assessment. RESULTS In Gr2, penetrating traumatic brain injury effect manifests as porencephalic cyst, 22.53 ± 2.87 (% of intact hemisphere), with p value of <0.0001 compared with uninjured Gr1. Group 3 lesion volume at 17.44 ± 2.11 did not differ significantly from Gr2 (p = 0.36), while Gr4 value, 9.17 ± 1.53, differed significantly (p = 0.0001). Engraftment and neuronal differentiation were significantly lower in the uninjured Gr1 (p < 0.05), compared with injured groups. However, there were no differences between Gr3 and Gr4. Significant increase in cortical tissue sparing (p = 0.03), including motor cortex (p = 0.005) was observed in Gr4 but not Gr3. Presence of transplant within lesion or in penumbra attenuated motor deficit development (p < 0.05) compared with Gr2. CONCLUSION In aggregate, injury milieu supports transplanted cell proliferation and differentiation independent of location. Unexpectedly, cortical sparing is transplant location dependent. Thus, apart from cell replacement and transplant mediated deficit amelioration, transplant location-dependent neuroprotection may be key to delaying onset or preventing development of injury-induced disability. LEVEL OF EVIDENCE Preclinical study evaluation of therapeutic intervention, level VI.
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Affiliation(s)
- Zhen Hu
- From the Department of Neurosurgery (Z.H.), Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, China; Miami Project to Cure Paralysis (Z.H., S.G., M.S.S., A.M., L.S.Q., G.R.G., C.B.A., L.D., J.J., S.W.L., K.N.R., R.M.D.), University of Miami, Miami, Florida; and Branch of Brain Trauma Neuroprotection and Neurorestoration (D.A.S.), Center for Military Psychiatry and Neuroscience, Walter Reed Army Institute of Research, Silver Spring, Maryland
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Van der Perren A, Macchi F, Toelen J, Carlon MS, Maris M, de Loor H, Kuypers DRJ, Gijsbers R, Van den Haute C, Debyser Z, Baekelandt V. FK506 reduces neuroinflammation and dopaminergic neurodegeneration in an α-synuclein-based rat model for Parkinson's disease. Neurobiol Aging 2015; 36:1559-68. [PMID: 25660193 DOI: 10.1016/j.neurobiolaging.2015.01.014] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2014] [Indexed: 10/24/2022]
Abstract
Alpha-synuclein (α-synuclein) is considered a key player in Parkinson's disease (PD), but the exact relationship between α-synuclein aggregation and dopaminergic neurodegeneration remains unresolved. There is increasing evidence that neuroinflammatory processes are closely linked to dopaminergic cell death, but whether the inflammatory process is causally involved in PD or rather reflects secondary consequences of nigrostriatal pathway injury is still under debate. We evaluated the therapeutic effect of the immunophilin ligand FK506 in a rAAV2/7 α-synuclein overexpression rat model. Treatment with FK506 significantly increased the survival of dopaminergic neurons in a dose-dependent manner. No reduction in α-synuclein aggregation was apparent in this time window, but FK506 significantly lowered the infiltration of both T helper and cytotoxic T cells and the number and subtype of microglia and macrophages. These data suggest that the anti-inflammatory properties of FK506 decrease neurodegeneration in this α-synuclein-based PD model, pointing to a causal role of neuroinflammation in the pathogenesis of PD.
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Affiliation(s)
- Anke Van der Perren
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Flanders, Belgium
| | - Francesca Macchi
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Flanders, Belgium
| | - Jaan Toelen
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Flanders, Belgium
| | - Marianne S Carlon
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Flanders, Belgium
| | - Michael Maris
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Flanders, Belgium
| | - Henriette de Loor
- Division of Nephrology and Renal Transplantation, Department of Microbiology and Immunology, Leuven University Hospital and KU Leuven, Leuven, Belgium
| | - Dirk R J Kuypers
- Division of Nephrology and Renal Transplantation, Department of Microbiology and Immunology, Leuven University Hospital and KU Leuven, Leuven, Belgium
| | - Rik Gijsbers
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Flanders, Belgium; Leuven Viral Vector Core, KU Leuven, Leuven, Belgium
| | - Chris Van den Haute
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Flanders, Belgium; Leuven Viral Vector Core, KU Leuven, Leuven, Belgium
| | - Zeger Debyser
- Molecular Virology and Gene Therapy, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Flanders, Belgium; Leuven Viral Vector Core, KU Leuven, Leuven, Belgium
| | - Veerle Baekelandt
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Flanders, Belgium; Leuven Viral Vector Core, KU Leuven, Leuven, Belgium.
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Arora RB, Kumar K, Deshmukh RR. FK506 attenuates intracerebroventricular streptozotocin-induced neurotoxicity in rats. Behav Pharmacol 2013; 24:580-9. [DOI: 10.1097/fbp.0b013e32836546db] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Toll EC, Seifalian AM, Birchall MA. The role of immunophilin ligands in nerve regeneration. Regen Med 2012; 6:635-52. [PMID: 21916598 DOI: 10.2217/rme.11.43] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Tacrolimus (FK506) is a widely used immunosuppressant in organ transplantation. However, it also has neurotrophic activity that occurs independently of its immunosuppressive effects. Other neurotrophic immunophilin ligands that do not exhibit immunosuppression have subsequently been developed and studied in various models of nerve injury. This article reviews the literature on the use of tacrolimus and other immunophilin ligands in peripheral nerve, cranial nerve and spinal cord injuries. The most convincing evidence of enhanced nerve regeneration is seen with systemic administration of tacrolimus in peripheral nerve injury, although clinical use is limited due to its immunosuppressive side effects. Local tacrolimus delivery to the site of nerve repair in peripheral and cranial nerve injury is less effective but requires further investigation. Tacrolimus can enhance outcomes in nerve allograft reconstruction and accelerates reinnervation of complex functional allograft transplants. Other non-immunosuppressive immunophilins ligands such as V-10367 and FK1706 demonstrate enhanced neuroregeneration in the peripheral nervous system and CNS. Mixed results are found in the application of immunophilin ligands to treat spinal cord injury. Immunophilin ligands have great potential in the treatment of nerve injury, but further preclinical studies are necessary to permit translation into clinical trials.
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Affiliation(s)
- Edward C Toll
- Division of Surgery and Interventional Science, University College London, UK.
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Wright AK, Garcia-Munoz M, Arbuthnott GW. Slowly progressive dopamine cell loss--a model on which to test neuroprotective strategies for Parkinson's disease? Rev Neurosci 2009; 20:85-94. [PMID: 19774787 DOI: 10.1515/revneuro.2009.20.2.85] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Making animal models of human disease is a very flawed process. Aspects of the disease can be imitated but models do not necessarily give reliable leads for treatment strategies. When Ungerstedt in Sweden first described the 6-hydroxydopamine (6-OHDA) treated rat model of Parkinson's disease /89/ we knew that the symptoms would not map readily to those of the human disease--rats have four legs after all. On the other hand, the neuropathology looked exactly like end-stage Parkinsonian pathology. That remained true even as we explored other types of neuropathology in the rats /24,43-46,80/. Many of today's treatments for Parkinsonism are developed from pharmacological studies on that model of rats with a chemically induced lesion. However, the 6-OHDA model does not address the important issue of a cure for the disease. The triggers and the time-course of dopamine (DA) cell death in rats are known for nearly every disease model - but for the human disease there is no equivalent knowledge. In the human, the neurons have been dying for a considerable time before the symptoms become obvious and they go on dying even with adequate symptomatic relief /94/, but after intracerebral administration of 6-OHDA to an animal the cells die quickly; all cells are destroyed in less than 5 days /42,88,89/. Thus, we were interested in developing an animal model of DA cell death with a slower time-course. After ibotenic acid injections into rat globus pallidus (GP), DA cells are lost from the ipsilateral substantia nigra over the slower time scale of about six weeks. This time scale has allowed us to test some interventions to prevent the cells from dying. Although some attempts have succeeded, cell death is prevented only for three weeks -beyond that treatments fail and DA cells die. At the moment, this model has at least opened a window into causes of neuronal death in a slower time scale /94/ than previous rodent models.
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Affiliation(s)
- Ann K Wright
- Brain Mechanisms for Behaviour Unit, Okinawa Institute of Science and Technology Promotion Corporation, Initial Research Project, Okinawa, Japan
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Polazzi E, Altamira LEP, Eleuteri S, Barbaro R, Casadio C, Contestabile A, Monti B. Neuroprotection of microglial conditioned medium on 6-hydroxydopamine-induced neuronal death: role of transforming growth factor beta-2. J Neurochem 2009; 110:545-56. [PMID: 19457129 DOI: 10.1111/j.1471-4159.2009.06117.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Microglia, the immune cells of the CNS, play essential roles in both physiological and pathological brain states. Here we have used an in vitro model to demonstrate neuroprotection of a 48 h-microglial conditioned medium (MCM) towards cerebellar granule neurons (CGNs) challenged with the neurotoxin 6-hydroxydopamine, which induces a Parkinson-like neurodegeneration, and to identify the protective factor(s). MCM nearly completely protects CGNs from 6-hydroxydopamine neurotoxicity and at least some of the protective factor(s) are peptidic in nature. While the fraction of the medium containing molecules < 30 kDa completely protects CGNs, fractions containing molecules < 10 kDa or > 10 kDa are not neuroprotective. We further demonstrate that microglia release high amounts of transforming growth factor-beta2 (TGF-beta2) and that its exogenous addition to the fraction of the medium not containing it (< 10 kDa) fully restores the neuroprotective action. Moreover, MCM neuroprotection is significantly counteracted by an inhibitor of TGF-beta2 transduction pathway. Our results identify TGF-beta2 as an essential neuroprotective factor released by microglia in its culture medium that requires to be fully effective the concomitant presence of other factor(s) of low molecular weight.
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Harry GJ, Kraft AD. Neuroinflammation and microglia: considerations and approaches for neurotoxicity assessment. Expert Opin Drug Metab Toxicol 2008; 4:1265-77. [PMID: 18798697 PMCID: PMC2658618 DOI: 10.1517/17425255.4.10.1265] [Citation(s) in RCA: 178] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The impact of an inflammatory response, as well as interactions between the immune and nervous systems, are rapidly assuming major roles in neurodegenerative disease and injury. However, it is now appreciated that the exact nature of such responses can differ with each type of insult and interaction. More recently, neuroinflammation and the associated cellular response of microglia are being considered for their contribution to neurotoxicity of environmental agents; yet, so far, the inclusion of inflammatory end points into neurotoxicity assessment have relied primarily on relatively limited measures or driven by in vitro models of neurotoxicity. OBJECTIVE To present background information on relevant biological considerations of neuroinflammation and the microglia response demonstrating the complex integrative nature of these biological processes and raising concern with regards to translation of effects demonstrated in vitro to the in vivo situation. Specific points are addressed that would influence the design and interpretation of neuroinflammation with regards to neurotoxicology assessment. CONCLUSION There is a complex and dynamic response in the brain to regulate inflammatory processes and maintain a normal homeostatic level. The classification of such responses as beneficial or detrimental is an oversimplification. Neuroinflammation should be considered as a balanced network of processes in which subtle modifications can shift the cells toward disparate outcomes. The tendency to overinterpret data obtained in an isolated culture system should be discouraged. Rather, the use of cross-disciplinary approaches to evaluate several end points should be incorporated into the assessment of inflammatory contributions to the neurotoxicity of environmental exposures.
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Affiliation(s)
- Gaylia Jean Harry
- National Institute of Environmental Health Sciences, National Institutes of Health, Neurotoxicology Group, Laboratory of Neurobiology, Department of Health and Human Services, Research Triangle Park, NC 27709, USA.
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