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Reiter RJ, Sharma RN, Manucha W, Rosales-Corral S, Almieda Chuffa LGD, Loh D, Luchetti F, Balduini W, Govitrapong P. Dysfunctional Mitochondria in Age-related Neurodegeneration: Utility of Melatonin as an Antioxidant Treatment. Ageing Res Rev 2024; 101:102480. [PMID: 39236857 DOI: 10.1016/j.arr.2024.102480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 08/18/2024] [Accepted: 08/28/2024] [Indexed: 09/07/2024]
Abstract
Mitochondria functionally degrade as neurons age. Degenerative changes cause inefficient oxidative phosphorylation (OXPHOS) and elevated electron leakage from the electron transport chain (ETC) promoting increased intramitochondrial generation of damaging reactive oxygen and reactive nitrogen species (ROS and RNS). The associated progressive accumulation of molecular damage causes an increasingly rapid decline in mitochondrial physiology contributing to aging. Melatonin, a multifunctional free radical scavenger and indirect antioxidant, is synthesized in the mitochondrial matrix of neurons. Melatonin reduces electron leakage from the ETC and elevates ATP production; it also detoxifies ROS/RNS and via the SIRT3/FOXO pathway it upregulates activities of superoxide dismutase 2 and glutathione peroxidase. Melatonin also influences glucose processing by neurons. In neurogenerative diseases, neurons often adopt Warburg-type metabolism which excludes pyruvate from the mitochondria causing reduced intramitochondrial acetyl coenzyme A production. Acetyl coenzyme A supports the citric acid cycle and OXPHOS. Additionally, acetyl coenzyme A is a required co-substrate for arylalkylamine-N-acetyl transferase, which rate limits melatonin synthesis; therefore, melatonin production is diminished in cells that experience Warburg-type metabolism making mitochondria more vulnerable to oxidative stress. Moreover, endogenously produced melatonin diminishes during aging, further increasing oxidative damage to mitochondrial components. More normal mitochondrial physiology is preserved in aging neurons with melatonin supplementation.
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Affiliation(s)
- Russel J Reiter
- Department of Cell Systems and Anatomy, UT Health San Antonio, Long School of Medicine, San Antonio, TX, USA.
| | - Ramaswamy N Sharma
- Applied Biomedical Sciences, University of the Incarnate Word, School of Osteopathic Medicine, San Antonio, TX, USA.
| | - Walter Manucha
- Instituto de Medicina y Biologia Experimental de Cuyo (IMBECU), Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CONICET), Mendoza 5500, Argentina.
| | - Sergio Rosales-Corral
- Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico.
| | - Luiz Gustavo de Almieda Chuffa
- Departamento de Biologia Estrutural e Funcional, Setor de Anatomia - Instituto de Biociências, IBB/UNESP, Campus Botucatu, Botucatu, São Paulo, Brazil.
| | - Doris Loh
- Independent Researcher, Marble Falls, TX, USA.
| | - Francesca Luchetti
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy.
| | - Walter Balduini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy.
| | - Piyarat Govitrapong
- Chulabhorn Graduate Institute, Chulabhorn Royal Academy, Laksi, Bangkok, Thailand.
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Pan S, Koleske JP, Koller GM, Halupnik GL, Alli AHO, Koneru S, DeFreitas D, Ramagiri S, Strahle JM. Postnatal meningeal CSF transport is primarily mediated by the arachnoid and pia maters and is not altered after intraventricular hemorrhage-posthemorrhagic hydrocephalus. Fluids Barriers CNS 2024; 21:4. [PMID: 38191402 PMCID: PMC10773070 DOI: 10.1186/s12987-023-00503-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 12/12/2023] [Indexed: 01/10/2024] Open
Abstract
BACKGROUND CSF has long been accepted to circulate throughout the subarachnoid space, which lies between the arachnoid and pia maters of the meninges. How the CSF interacts with the cellular components of the developing postnatal meninges including the dura, arachnoid, and pia of both the meninges at the surface of the brain and the intracranial meninges, prior to its eventual efflux from the cranium and spine, is less understood. Here, we characterize small and large CSF solute distribution patterns along the intracranial and surface meninges in neonatal rodents and compare our findings to meningeal CSF solute distribution in a rodent model of intraventricular hemorrhage-posthemorrhagic hydrocephalus. We also examine CSF solute interactions with the tela choroidea and its pial invaginations into the choroid plexuses of the lateral, third, and fourth ventricles. METHODS 1.9-nm gold nanoparticles, 15-nm gold nanoparticles, or 3 kDa Red Dextran Tetramethylrhodamine constituted in aCSF were infused into the right lateral ventricle of P7 rats to track CSF circulation. 10 min post-1.9-nm gold nanoparticle and Red Dextran Tetramethylrhodamine injection and 4 h post-15-nm gold nanoparticle injection, animals were sacrificed and brains harvested for histologic analysis to identify CSF tracer localization in the cranial and spine meninges and choroid plexus. Spinal dura and leptomeninges (arachnoid and pia) wholemounts were also evaluated. RESULTS There was significantly less CSF tracer distribution in the dura compared to the arachnoid and pia maters in neonatal rodents. Both small and large CSF tracers were transported intracranially to the arachnoid and pia mater of the perimesencephalic cisterns and tela choroidea, but not the falx cerebri. CSF tracers followed a similar distribution pattern in the spinal meninges. In the choroid plexus, there was large CSF tracer distribution in the apical surface of epithelial cells, and small CSF tracer along the basolateral surface. There were no significant differences in tracer intensity in the intracranial meninges of control vs. intraventricular hemorrhage-posthemorrhagic hydrocephalus (PHH) rodents, indicating preserved meningeal transport in the setting of PHH. CONCLUSIONS Differential CSF tracer handling by the meninges suggests that there are distinct roles for CSF handling between the arachnoid-pia and dura maters in the developing brain. Similarly, differences in apical vs. luminal choroid plexus CSF handling may provide insight into particle-size dependent CSF transport at the CSF-choroid plexus border.
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Affiliation(s)
- Shelei Pan
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Joshua P Koleske
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Gretchen M Koller
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Grace L Halupnik
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Abdul-Haq O Alli
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Shriya Koneru
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Dakota DeFreitas
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sruthi Ramagiri
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Jennifer M Strahle
- Department of Neurosurgery, Washington University School of Medicine, Washington University in St. Louis, St. Louis, MO, 63110, USA.
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Pan S, Koleske J, Koller GM, Halupnik GL, Alli AHO, Koneru S, DeFreitas D, Ramagiri U, Strahle JM. Meningeal CSF transport is primarily mediated by the arachnoid and pia maters during development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.10.552826. [PMID: 37645776 PMCID: PMC10461931 DOI: 10.1101/2023.08.10.552826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Background The recent characterization of the glymphatic system and meningeal lymphatics has re-emphasized the role of the meninges in facilitating CSF transport and clearance. Here, we characterize small and large CSF solute distribution patterns along the intracranial and surface meninges in neonatal rodents and compare our findings to a rodent model of intraventricular hemorrhage-posthemorrhagic hydrocephalus. We also examine CSF interactions with the tela choroidea and its pial invaginations into the choroid plexuses of the lateral, third, and fourth ventricles. Methods 1.9-nm gold nanoparticles, 15-nm gold nanoparticles, or 3 kDa Red Dextran Tetramethylrhodamine constituted in aCSF were infused into the right lateral ventricle of P7 rats to track CSF circulation. 10 minutes post-1.9-nm gold nanoparticle and Red Dextran Tetramethylrhodamine injection and 4 hours post-15-nm gold nanoparticle injection, animals were sacrificed and brains harvested for histologic analysis to identify CSF tracer localization in the cranial and spine meninges and choroid plexus. Spinal dura and leptomeninges (arachnoid and pia) wholemounts were also performed. Results There was significantly less CSF tracer distribution in the dura compared to the arachnoid and pia maters in neonatal rodents. Both small and large CSF tracers were transported intracranially to the arachnoid and pia mater of the perimesencephalic cisterns and tela choroidea, but not the dura mater of the falx cerebri. CSF tracers followed a similar distribution pattern in the spinal meninges. In the choroid plexus, there was large CSF tracer distribution in the apical surface of epithelial cells, and small CSF tracer along the basolateral surface. There were no significant differences in tracer intensity in the intracranial meninges of control vs. intraventricular hemorrhage-posthemorrhagic hydrocephalus (PHH) rodents, indicating preserved meningeal transport in the setting of PHH. Conclusions Differential CSF tracer handling by the leptomeninges suggests that there are distinct roles for CSF handling between the arachnoid-pia and dura maters in the developing brain. Similarly, differences in apical vs. luminal choroid plexus CSF handling may provide insight into particle-size dependent CSF transport at the CSF-choroid plexus border.
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Abstract
Accumulation of toxic protein aggregates-amyloid-β (Aβ) plaques and hyperphosphorylated tau tangles-is the pathological hallmark of Alzheimer disease (AD). Aβ accumulation has been hypothesized to result from an imbalance between Aβ production and clearance; indeed, Aβ clearance seems to be impaired in both early and late forms of AD. To develop efficient strategies to slow down or halt AD, it is critical to understand how Aβ is cleared from the brain. Extracellular Aβ deposits can be removed from the brain by various clearance systems, most importantly, transport across the blood-brain barrier. Findings from the past few years suggest that astroglial-mediated interstitial fluid (ISF) bulk flow, known as the glymphatic system, might contribute to a larger portion of extracellular Aβ (eAβ) clearance than previously thought. The meningeal lymphatic vessels, discovered in 2015, might provide another clearance route. Because these clearance systems act together to drive eAβ from the brain, any alteration to their function could contribute to AD. An understanding of Aβ clearance might provide strategies to reduce excess Aβ deposits and delay, or even prevent, disease onset. In this Review, we describe the clearance systems of the brain as they relate to proteins implicated in AD pathology, with the main focus on Aβ.
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Jessen NA, Munk ASF, Lundgaard I, Nedergaard M. The Glymphatic System: A Beginner's Guide. Neurochem Res 2015; 40:2583-99. [PMID: 25947369 DOI: 10.1007/s11064-015-1581-6] [Citation(s) in RCA: 1058] [Impact Index Per Article: 117.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 04/06/2015] [Accepted: 04/10/2015] [Indexed: 12/16/2022]
Abstract
The glymphatic system is a recently discovered macroscopic waste clearance system that utilizes a unique system of perivascular tunnels, formed by astroglial cells, to promote efficient elimination of soluble proteins and metabolites from the central nervous system. Besides waste elimination, the glymphatic system also facilitates brain-wide distribution of several compounds, including glucose, lipids, amino acids, growth factors, and neuromodulators. Intriguingly, the glymphatic system function mainly during sleep and is largely disengaged during wakefulness. The biological need for sleep across all species may therefore reflect that the brain must enter a state of activity that enables elimination of potentially neurotoxic waste products, including β-amyloid. Since the concept of the glymphatic system is relatively new, we will here review its basic structural elements, organization, regulation, and functions. We will also discuss recent studies indicating that glymphatic function is suppressed in various diseases and that failure of glymphatic function in turn might contribute to pathology in neurodegenerative disorders, traumatic brain injury and stroke.
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Affiliation(s)
- Nadia Aalling Jessen
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 645, Rochester, NY, 14642, USA.
| | - Anne Sofie Finmann Munk
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 645, Rochester, NY, 14642, USA
| | - Iben Lundgaard
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 645, Rochester, NY, 14642, USA
| | - Maiken Nedergaard
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 645, Rochester, NY, 14642, USA
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Delivery of pineal melatonin to the brain and SCN: role of canaliculi, cerebrospinal fluid, tanycytes and Virchow–Robin perivascular spaces. Brain Struct Funct 2014; 219:1873-87. [DOI: 10.1007/s00429-014-0719-7] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 01/28/2014] [Indexed: 12/17/2022]
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Maurizi CP. Choroid plexus portals and a deficiency of melatonin can explain the neuropathology of Alzheimer’s disease. Med Hypotheses 2010; 74:1059-66. [DOI: 10.1016/j.mehy.2009.12.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 12/19/2009] [Indexed: 11/16/2022]
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Comai S, Longatti P, Perin A, Bertazzo A, Ragazzi E, Costa CVL, Allegri G. Study of tryptophan metabolism via serotonin in cerebrospinal fluid of patients with noncommunicating hydrocephalus using a new endoscopic technique. J Neurosci Res 2006; 84:683-91. [PMID: 16721766 DOI: 10.1002/jnr.20958] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
By a recent minimally invasive neuroendoscopic technique, the cerebral ventricles have been reached in a quick, reliable, and harmless way, making possible the study of cerebrospinal fluid (CSF) of the lateral ventricles and, above all, the CSF adjacent to the walls of the third ventricle. Tryptophan, 5-hydroxytryptophan, serotonin (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) were measured in CSF by HPLC equipment. Twenty-six patients affected with noncommunicating hydrocephalus were enrolled in the study and, as controls, 28 subjects not suffering from any neurological disease. The concentrations of tryptophan were higher in right ventricular CSF than in lumbar CSF (P < 0.01). 5-HT was detectable in the CSF of the right ventricle of hydrocephalic patients. 5-HIAA was higher in right ventricular CSF than in cisternal and lumbar CSF (P < 0.01), both in controls and in hydrocephalic patients. However, there was a higher concentration of 5-HIAA in right ventricular (P < 0.05) and cisternal (P < 0.01) CSF in hydrocephalic patients in comparison with controls. In the CSF samples withdrawn during neuroendoscopy, 5-HT presented the highest concentrations in the pineal recess. The highest amounts of 5-HIAA were found in the choroid plexus, third and right ventricles, pituitary recess, and aqueduct, and the lowest in pineal recess, subarachnoid space, infundibulum, and interpeduncolar cistern. These results provide new insight into the fate of tryptophan and its metabolites via serotonin in the CSF and suggest the feasibility of the new neuroendoscopic technique for brain metabolic studies.
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Affiliation(s)
- Stefano Comai
- Department of Pharmaceutical Sciences, University of Padova, Padova, Italy
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Tricoire H, Locatelli A, Chemineau P, Malpaux B. Melatonin enters the cerebrospinal fluid through the pineal recess. Endocrinology 2002; 143:84-90. [PMID: 11751596 DOI: 10.1210/endo.143.1.8585] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The pineal recess (PR), a third ventricle (IIIV) evagination penetrating into the pineal gland, could constitute a site of melatonin passage to the cerebrospinal fluid (CSF) and explain the high concentrations of melatonin in this fluid. To test this hypothesis, we characterized melatonin distribution in the IIIV of sheep by CSF collection in the ventral part of IIIV (vIIIV) and in PR. At 30 microl/min collection rate, melatonin concentrations were much higher in PR than in vIIIV (19,934 +/- 6,388 vs. 178 +/- 70 pg/ml, mean +/- SEM, respectively, P < 0.005), and they increased in vIIIV when CSF collection stopped in the PR (P < 0.05). At 6 microl/min, levels increased to 1,682 +/- 585 pg/ml in vIIIV and were not influenced by CSF collection in the PR. This concentration difference between sites and the influence of PR collection on vIIIV levels suggest that melatonin reaches the PR and then diffuses to the IIIV. To confirm the role of PR, we demonstrated that its surgical sealing off decreased IIIV melatonin levels (1,020 +/- 305 pg/ml, compared with 5,984 +/- 1,706 and 6,917 +/- 1,601 pg/ml in shams or animals with a failed sealing off, respectively, P < 0.01) without changes in blood levels. Therefore, this study identified the localization of the main site of penetration of melatonin into the CSF, the pineal recess.
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Affiliation(s)
- Hélène Tricoire
- Unité Mixte de Recherche Institut National de la Recherche Agronomique-Centre National de la Recherche Scientifique (6073), Université de Tours "Physiologie de la Reproduction et des Comportements," 37380 Nouzilly, France
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Maurizi CP. A cycle of cerebrospinal fluid: supporting evidence and theoretical considerations. Med Hypotheses 2000; 54:417-22. [PMID: 10783477 DOI: 10.1054/mehy.1999.0863] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An entrenched theory of cerebrospinal fluid (CSF) absorption by the arachnoid villi fails to explain observations regarding the movement of substances in the fluid. Experiments that demonstrated the arachnoid villi as the site of absorption were based on non-physiologic methods. CSF does not flow through the arachnoid villi, because villi require bulk flow and bulk flow of CSF does not exist. CSF is transported through the choroid fissure and recycled through the tela choroidae by the choroid plexus, with reentry into the ventricular system. Observed failures of the effete arachnoid villus theory can be readily explained by the cycling theory. A complete cycle of CSF is suggested to pace the 90 to 100-minute ultradian rhythms found in human physiology.
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Affiliation(s)
- C P Maurizi
- Department of Pathology, Houston Medical Center, Warner Robins, GA, USA
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Skinner DC, Malpaux B. High melatonin concentrations in third ventricular cerebrospinal fluid are not due to Galen vein blood recirculating through the choroid plexus. Endocrinology 1999; 140:4399-405. [PMID: 10499491 DOI: 10.1210/endo.140.10.7074] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Melatonin has been implicated in several neurotropic effects, but few studies have investigated the bioavailability of melatonin in the brain. The discovery of periventricular sites of action adjacent to the third ventricle forced us to investigate the dynamics of cerebrospinal fluid (CSF) melatonin release and the source of this melatonin. Our first study demonstrated unequivocally that third ventricle CSF melatonin, like jugular plasma melatonin, accurately reflects the duration of the night and is rapidly suppressed by light. However, third ventricle CSF melatonin levels are 20-fold higher than nocturnal plasma concentrations. A further study showed that melatonin increased in plasma before third ventricle CSF, raising the possibility that melatonin is taken up from the blood after recirculation through the Galen vein. However, a final experiment suggested strongly that CSF melatonin is released directly into the third ventricle, as melatonin levels in the lateral ventricle were 7-fold lower than those in the third ventricle. Our study raises the possibility that there may be two compartments of melatonin affecting physiological functioning: the first in plasma acting on peripheral organs, and the second in the CSF affecting neurally mediated functions at a much higher concentration of this pineal indoleamine.
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Affiliation(s)
- D C Skinner
- Institut National de la Recherche Agronomique, Physiologie de la Reproduction des Mammiferes Domestiques, Nouzilly, France
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Maurizi CP. Loss of intraventricular fluid melatonin can explain the neuropathology of Alzheimer's disease. Med Hypotheses 1997; 49:153-8. [PMID: 9278927 DOI: 10.1016/s0306-9877(97)90220-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Loss of intraventricular fluid melatonin explains why Alzheimer's disease neuropathology has a laminar, regional and neural-system-specific pattern, which includes the entorhinal cortex, CA1 of the hippocampus, the dorsal raphe nucleus and the locus ceruleus. High metabolic activity may be part of the neuronal vulnerability. Without elevated levels of ventricular fluid melatonin, the hydroxyl radical damages the mitochondria of the most active neurons, causing apoptosis, with resultant failure of the memory system. General brain atrophy follows in the absence of new memory formation.
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Affiliation(s)
- C P Maurizi
- Department of Pathology, Houston Medical Center, Warner Robins, GA 31093, USA
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Maurizi CP. Superficial siderosis of the brain: roles for cerebrospinal fluid circulation, iron and the hydroxyl radical. Med Hypotheses 1996; 47:261-4. [PMID: 8910872 DOI: 10.1016/s0306-9877(96)90063-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Superficial siderosis is associated with chronic blood loss into the cerebrospinal fluid. The pattern of hemosiderin deposition and clinical signs in superficial siderosis suggest that cerebrospinal fluid is recirculated into the ventricular system. Patterns of deposition of corpora amylacea and findings in normopressure communicating hydrocephalus also support the recirculation theory. 'Free' iron with excess production of hydroxyl radicals is the probable mechanism of tissue damage. The arachnoid villus-superior saggital sinus theory of cerebrospinal fluid circulation should be abandoned.
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Affiliation(s)
- C P Maurizi
- Department of Pathology, Houston Medical Center, Warner Robins, GA 31093, USA
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