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Pi H, Xu S, Reiter RJ, Guo P, Zhang L, Li Y, Li M, Cao Z, Tian L, Xie J, Zhang R, He M, Lu Y, Liu C, Duan W, Yu Z, Zhou Z. SIRT3-SOD2-mROS-dependent autophagy in cadmium-induced hepatotoxicity and salvage by melatonin. Autophagy 2016; 11:1037-51. [PMID: 26120888 PMCID: PMC4590599 DOI: 10.1080/15548627.2015.1052208] [Citation(s) in RCA: 249] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cadmium is one of the most toxic metal compounds found in the environment. It is well established that Cd induces hepatotoxicity in humans and multiple animal models. Melatonin, a major secretory product of the pineal gland, has been reported to protect against Cd-induced hepatotoxicity. However, the mechanism behind this protection remains to be elucidated. We exposed HepG2 cells to different concentrations of cadmium chloride (2.5, 5, and 10 μM) for 12 h. We found that Cd induced mitochondrial-derived superoxide anion-dependent autophagic cell death. Specifically, Cd decreased SIRT3 protein expression and activity and promoted the acetylation of SOD2, superoxide dismutase 2, mitochondrial, thus decreasing its activity, a key enzyme involved in mitochondrial ROS production, although Cd did not disrupt the interaction between SIRT3 and SOD2. These effects were ameliorated by overexpression of SIRT3. However, a catalytic mutant of SIRT3 (SIRT3H248Y) lacking deacetylase activity lost the capacity to suppress Cd-induced autophagy. Notably, melatonin treatment enhanced the activity but not the expression of SIRT3, decreased the acetylation of SOD2, inhibited mitochondrial-derived O2•− production and suppressed the autophagy induced by 10 μM Cd. Moreover, 3-(1H-1,2,3-triazol-4-yl)pyridine, a confirmed selective SIRT3 inhibitor, blocked the melatonin-mediated suppression of autophagy by inhibiting SIRT3-SOD2 signaling. Importantly, melatonin suppressed Cd-induced autophagic cell death by enhancing SIRT3 activity in vivo. These results suggest that melatonin exerts a hepatoprotective effect on mitochondrial-derived O2•−-stimulated autophagic cell death that is dependent on the SIRT3/SOD2 pathway.
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Key Words
- 3-MA, 3-methyladenine
- 3-TYP, 3-(1H-1,2,3-triazol-4-yl)pyridine
- ACTB, actin, β
- Baf A1, bafilomycin A1
- Cd, cadmium
- CdCl2, cadmium chloride
- GPT/ALT, glutamic-pyruvate transaminase (alanine aminotransferase)
- H2O2, hydrogen peroxide
- LC3, microtubule-associated protein 1 light chain 3
- O2•−, superoxide anion
- SIRT1, sirtuin 1
- SIRT3
- SIRT3, sirtuin 3
- SOD2
- SOD2, superoxide dismutase 2, mitochondrial
- SQSTM1/p62, sequestosome 1
- autophagy
- cadmium
- hepatotoxicity
- mROS, mitochondrial reactive oxygen species
- mel, melatonin
- melatonin
- mitochondrial ROS
- tf-LC3, tandem fluorescent mRFP-GFP-LC3B
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Affiliation(s)
- Huifeng Pi
- a Department of Occupational Health; Third Military Medical University ; Chongqing , China
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Melatonin Suppresses Autophagy Induced by Clinostat in Preosteoblast MC3T3-E1 Cells. Int J Mol Sci 2016; 17:526. [PMID: 27070587 PMCID: PMC4848982 DOI: 10.3390/ijms17040526] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 03/25/2016] [Accepted: 04/05/2016] [Indexed: 02/06/2023] Open
Abstract
Microgravity exposure can cause cardiovascular and immune disorders, muscle atrophy, osteoporosis, and loss of blood and plasma volume. A clinostat device is an effective ground-based tool for simulating microgravity. This study investigated how melatonin suppresses autophagy caused by simulated microgravity in preosteoblast MC3T3-E1 cells. In preosteoblast MC3T3-E1 cells, clinostat rotation induced a significant time-dependent increase in the levels of the autophagosomal marker microtubule-associated protein light chain (LC3), suggesting that autophagy is induced by clinostat rotation in these cells. Melatonin treatment (100, 200 nM) significantly attenuated the clinostat-induced increases in LC3 II protein, and immunofluorescence staining revealed decreased levels of both LC3 and lysosomal-associated membrane protein 2 (Lamp2), indicating a decrease in autophagosomes. The levels of phosphorylation of mammalian target of rapamycin (p-mTOR) (Ser2448), phosphorylation of extracellular signal-regulated kinase (p-ERK), and phosphorylation of serine-threonine protein kinase (p-Akt) (Ser473) were significantly reduced by clinostat rotation. However, their expression levels were significantly recovered by melatonin treatment. Also, expression of the Bcl-2, truncated Bid, Cu/Zn- superoxide dismutase (SOD), and Mn-SOD proteins were significantly increased by melatonin treatment, whereas levels of Bax and catalase were decreased. The endoplasmic reticulum (ER) stress marker GRP78/BiP, IRE1α, and p-PERK proteins were significantly reduced by melatonin treatment. Treatment with the competitive melatonin receptor antagonist luzindole blocked melatonin-induced decreases in LC3 II levels. These results demonstrate that melatonin suppresses clinostat-induced autophagy through increasing the phosphorylation of the ERK/Akt/mTOR proteins. Consequently, melatonin appears to be a potential therapeutic agent for regulating microgravity-related bone loss or osteoporosis.
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53
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Brain metabolism as a modulator of autophagy in neurodegeneration. Brain Res 2016; 1649:158-165. [PMID: 26970520 DOI: 10.1016/j.brainres.2016.02.049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 02/03/2016] [Accepted: 02/16/2016] [Indexed: 12/19/2022]
Abstract
Emerging evidence that autophagy serves as a sweeper for toxic materials in the brain gives us new insight into the pathophysiology of neurodegenerative diseases. Autophagy is important for maintaining cellular homeostasis associated with metabolism. Some neurodegenerative diseases such as Alzheimer׳s and Parkinson׳s diseases are accompanied by altered metabolism and autophagy in the brain. In this review, we discuss how hormones and nutrients regulate autophagy in the brain and affect neurodegeneration. This article is part of a Special Issue entitled SI:Autophagy.
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Umpierre AD, Bennett IV, Nebeker LD, Newell TG, Tian BB, Thomson KE, White HS, White JA, Wilcox KS. Repeated low-dose kainate administration in C57BL/6J mice produces temporal lobe epilepsy pathology but infrequent spontaneous seizures. Exp Neurol 2016; 279:116-126. [PMID: 26896834 DOI: 10.1016/j.expneurol.2016.02.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/29/2016] [Accepted: 02/15/2016] [Indexed: 12/31/2022]
Abstract
More efficient or translationally relevant approaches are needed to model acquired temporal lobe epilepsy (TLE) in genetically tractable mice. The high costs associated with breeding and maintaining transgenic, knock-in, or knock-out lines place a high value on the efficiency of induction and animal survivability. Herein, we describe our approaches to model acquired epilepsy in C57BL/6J mice using repeated, low-dose kainate (KA) administration paradigms. Four paradigms (i.p.) were tested for their ability to induce status epilepticus (SE), temporal lobe pathology, and the development of epilepsy. All four paradigms reliably induce behavioral and/or electrographic SE without mortality over a 7d period. Two of the four paradigms investigated produce features indicative of TLE pathology, including hippocampal cell death, widespread astrogliosis, and astrocyte expression of mGluR5, a feature commonly reported in TLE models. Three of the investigated paradigms were able to produce aberrant electrographic features, such as interictal spiking in cortex. However, only one paradigm, previously published by others, produces spontaneous recurrent seizures over an eight week period. Presentation of spontaneous seizures is rare (N=2/14), with epilepsy preferentially developing in animals having a high number of seizures during SE. Overall, repeated, low-dose KA administration improves the efficiency and pathological relevance of a systemic KA insult, but does not produce a robust epilepsy phenotype under the experimental paradigms described herein.
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Affiliation(s)
- Anthony D Umpierre
- Interdepartmental Program in Neuroscience, University of Utah, 401 MREB, 20N. 1900E, Salt Lake City, UT 84132, United States.
| | - Isaiah V Bennett
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Lismore D Nebeker
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Thomas G Newell
- Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Dept. of Bioengineering, University of Utah, 36S. Wasatch Drive, Rm. 3100, Salt Lake City, UT 84112, United States.
| | - Bruce B Tian
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Kyle E Thomson
- Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Dept. of Bioengineering, University of Utah, 36S. Wasatch Drive, Rm. 3100, Salt Lake City, UT 84112, United States.
| | - H Steve White
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States; Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Department of Pharmacy, University of Washington, Box 357630, H375 Health Science Building, Seattle, WA 98195, United States.
| | - John A White
- Dept. of Biomedical Engineering, Boston University, 44 Cummington Mall, Rm. 403, Boston, MA 02215, United States.
| | - Karen S Wilcox
- Interdepartmental Program in Neuroscience, University of Utah, 401 MREB, 20N. 1900E, Salt Lake City, UT 84132, United States; Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States; Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States.
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Marseglia L, D'Angelo G, Manti S, Reiter RJ, Gitto E. Potential Utility of Melatonin in Preeclampsia, Intrauterine Fetal Growth Retardation, and Perinatal Asphyxia. Reprod Sci 2015; 23:970-7. [PMID: 26566856 DOI: 10.1177/1933719115612132] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
AIM Reactive oxygen species play an important role in the pathogenesis of several diseases during gestation and the perinatal period. During pregnancy, increased oxygen demand augments the rate of production of free radicals. Oxidative stress is involved in pregnancy disorders including preeclampsia and intrauterine fetal growth retardation (IUGR). Moreover, increased levels of oxidative stress and reduced antioxidative capacities may contribute to the pathogenesis of perinatal asphyxia. Melatonin, an efficient antioxidant agent, diffuses through biological membranes easily and exerts pleiotropic actions on every cell and appears to be essential for successful gestation. This narrative review summarizes current knowledge concerning the role of melatonin in reducing complications during human pregnancy and in the perinatal period. RESULTS Melatonin levels are altered in women with abnormally functioning placentae during preeclampsia and IUGR. Short-term melatonin therapy is highly effective and safe in reducing complications during pregnancy and in the perinatal period. Because melatonin has been shown to be safe for both mother and fetus, it could be an attractive therapy in pregnancy and is considered a promising neuroprotective agent in perinatal asphyxia. CONCLUSION We believe that the use of melatonin treatment during the late fetal and early neonatal period might result in a wide range of health benefits, improved quality of life, and may help limit complications during the critical periods prior to, and shortly after, delivery.
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Affiliation(s)
- Lucia Marseglia
- Neonatal and Pediatric Intensive Care Unit, Department of Pediatrics, University of Messina, Messina, Italy
| | - Gabriella D'Angelo
- Neonatal and Pediatric Intensive Care Unit, Department of Pediatrics, University of Messina, Messina, Italy
| | - Sara Manti
- Neonatal and Pediatric Intensive Care Unit, Department of Pediatrics, University of Messina, Messina, Italy
| | - Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Eloisa Gitto
- Neonatal and Pediatric Intensive Care Unit, Department of Pediatrics, University of Messina, Messina, Italy
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Ding K, Xu J, Wang H, Zhang L, Wu Y, Li T. Melatonin protects the brain from apoptosis by enhancement of autophagy after traumatic brain injury in mice. Neurochem Int 2015; 91:46-54. [PMID: 26527380 DOI: 10.1016/j.neuint.2015.10.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/27/2015] [Accepted: 10/20/2015] [Indexed: 12/13/2022]
Abstract
Melatonin has been proven to possess neuroprotection property against various neurological diseases by decreasing cerebral oxidative stress and inhibiting inflammatory process. However, whether administration of melatonin influences the autophagy pathway, which has recently been reported playing a pivotal role in traumatic brain injury, is yet not fully understood. We supposed that treatment of melatonin enhances the autophagy pathway after traumatic brain injury (TBI) in mice and subsequently inhibited the mitochondrion apoptotic pathway. Firstly, we investigated the neurological severity score, brain water content and neuronal apoptosis in mice cortex to demonstrate the neuroprotection of melatonin. Then we determined the autophagy markers, namely Beclin1 and LC3-II, using western blot and immunofluorescence. Next, we evaluated the mitochondrial apoptotic pathway in the presence or absence of melatonin. More significantly, we employed 3-methyladenine (3-MA) to inhibit the autophagy pathway, to further confirm our hypothesis. The results showed that melatonin significantly ameliorated secondary brain injury induced by TBI. In addition, melatonin enhanced autophagy after TBI, which was accompanied by a decrease in both the translocation of Bax to mitochondria and the release of cytochrome C to cytoplasm. Furthermore, simultaneous treatment of 3-MA reversed the beneficial effects of melatonin on mitochondrial apoptotic pathway. Taken together, we conclude that melatonin enhances autophagy, which inhibits mitochondrial apoptotic pathway, thus protecting mice from secondary brain injury after TBI.
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Affiliation(s)
- Ke Ding
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China
| | - Jianguo Xu
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China
| | - Handong Wang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China.
| | - Li Zhang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China
| | - Yong Wu
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China
| | - Tao Li
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China
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Cognitive deficits and anxiety induced by diisononyl phthalate in mice and the neuroprotective effects of melatonin. Sci Rep 2015; 5:14676. [PMID: 26424168 PMCID: PMC4589782 DOI: 10.1038/srep14676] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 09/07/2015] [Indexed: 12/15/2022] Open
Abstract
Diisononyl phthalate (DINP) is a plasticizer that is frequently used as a substitute for other plasticizers whose use is prohibited in certain products. In vivo studies on the neurotoxicity of DINP are however, limited. This work aims to investigate whether DINP causes neurobehavioral changes in mice and to provide useful advice on preventing the occurrence of these adverse effects. Behavioral analysis showed that oral administration of 20 or 200 mg/kg/day DINP led to mouse cognitive deficits and anxiety. Brain histopathological observations, immunohistochemistry assays (cysteine-aspartic acid protease 3 [caspase-3], glial fibrillary acidic protein [GFAP]), oxidative stress assessments (reactive oxygen species [ROS], glutathione [GSH], superoxide dismutase [SOD] activities, 8-hydroxy-2-deoxyguanosine [8-OH-dG] and DNA-protein crosslinks [DPC]), and assessment of inflammation (tumor necrosis factor alpha [TNF-а] and interleukin-1 beta [IL-1β]) of mouse brains showed that there were histopathological alterations in the brain and increased levels of oxidative stress, and inflammation for these same groups. However, some of these effects were blocked by administration of melatonin (50 mg/kg/day). Down-regulation of oxidative stress was proposed to explain the neuroprotective effects of melatonin. The data suggests that DINP could cause cognitive deficits and anxiety in mice, and that melatonin could be used to avoid these adverse effects.
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Ali T, Kim MO. Melatonin ameliorates amyloid beta-induced memory deficits, tau hyperphosphorylation and neurodegeneration via PI3/Akt/GSk3β pathway in the mouse hippocampus. J Pineal Res 2015; 59:47-59. [PMID: 25858697 DOI: 10.1111/jpi.12238] [Citation(s) in RCA: 159] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 04/03/2015] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent age-related neurodegenerative disease, pathologically characterized by the accumulation of amyloid beta (Aβ) aggregation in the brain, and is considered to be the primary cause of cognitive dysfunction. Aβ aggregates lead to synaptic disorder, tau hyperphosphorylation, and neurodegeneration. In this study, the underlying neuroprotective mechanism of melatonin against Aβ1-42-induced neurotoxicity was investigated in the mice hippocampus. Intracerebroventricular (i.c.v.) Aβ1-42-injection triggered memory impairment, synaptic disorder, hyperphosphorylation of tau protein, and neurodegeneration in the mice hippocampus. After 24 hr of Aβ1-42 injection, the mice were treated with melatonin (10 mg/kg, intraperitonially) for 3 wks, reversed the Aβ1-42-induced synaptic disorder via increasing the level of presyanptic (Synaptophysin and SNAP-25) and postsynaptic protein [PSD95, p-GluR1 (Ser845), SNAP23, and p-CREB (Ser133)], respectively, and attenuated the Aβ1-42-induced memory impairment. Chronic melatonin treatment attenuated the hyperphosphorylation of tau protein via PI3K/Akt/GSK3β signaling by activating the p-PI3K, p-Akt (Ser 473) and p-GSK3β (Ser9) in the Aβ1-42-treated mice. Furthermore, melatonin decreased Aβ1-42 -induced apoptosis through decreasing the overexpression of caspase-9, caspase-3, and PARP-1 level. Additionally, the evaluation of immunohistochemical analysis of caspase-3, Fluorojade-B, and Nissl staining indicated that melatonin prevented neurodegeneration in Aβ1-42-treated mice. Our results demonstrated that melatonin has neuroprotective effect against Aβ1-42-induced neurotoxicity through decreasing memory impairment, synaptic disorder, tau hyperphosphorylation, and neurodegeneration via PI3K/Akt/GSK3β signaling in the Aβ1-42-treated mouse model of AD. On the basis of these results, we suggest that melatonin could be an effective, promising, and safe neuroprotective candidate for the treatment of progressive neurodegenerative disorders, such as AD.
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Affiliation(s)
- Tahir Ali
- Department of Biology and Applied Life Science (BK 21), College of Natural Sciences (RINS), Gyeongsang National University, Jinju, Korea
| | - Myeong Ok Kim
- Department of Biology and Applied Life Science (BK 21), College of Natural Sciences (RINS), Gyeongsang National University, Jinju, Korea
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Descloux C, Ginet V, Clarke PGH, Puyal J, Truttmann AC. Neuronal death after perinatal cerebral hypoxia-ischemia: Focus on autophagy-mediated cell death. Int J Dev Neurosci 2015. [PMID: 26225751 DOI: 10.1016/j.ijdevneu.2015.06.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Neonatal hypoxic-ischemic encephalopathy is a critical cerebral event occurring around birth with high mortality and neurological morbidity associated with long-term invalidating sequelae. In view of the great clinical importance of this condition and the lack of very efficacious neuroprotective strategies, it is urgent to better understand the different cell death mechanisms involved with the ultimate aim of developing new therapeutic approaches. The morphological features of three different cell death types can be observed in models of perinatal cerebral hypoxia-ischemia: necrotic, apoptotic and autophagic cell death. They may be combined in the same dying neuron. In the present review, we discuss the different cell death mechanisms involved in neonatal cerebral hypoxia-ischemia with a special focus on how autophagy may be involved in neuronal death, based: (1) on experimental models of perinatal hypoxia-ischemia and stroke, and (2) on the brains of human neonates who suffered from neonatal hypoxia-ischemia.
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Affiliation(s)
- C Descloux
- Department of Fundamental Neurosciences (DNF), University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland; Clinic of Neonatology, Department of Pediatrics and Pediatric Surgery, University Hospital Center and University of Lausanne, 1011 Lausanne, Vaud, Switzerland
| | - V Ginet
- Department of Fundamental Neurosciences (DNF), University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - P G H Clarke
- Department of Fundamental Neurosciences (DNF), University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
| | - J Puyal
- Department of Fundamental Neurosciences (DNF), University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland; Clinic of Neonatology, Department of Pediatrics and Pediatric Surgery, University Hospital Center and University of Lausanne, 1011 Lausanne, Vaud, Switzerland
| | - A C Truttmann
- Department of Fundamental Neurosciences (DNF), University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland; Clinic of Neonatology, Department of Pediatrics and Pediatric Surgery, University Hospital Center and University of Lausanne, 1011 Lausanne, Vaud, Switzerland.
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Teng YC, Tai YI, Huang HJ, Lin AMY. Melatonin Ameliorates Arsenite-Induced Neurotoxicity: Involvement of Autophagy and Mitochondria. Mol Neurobiol 2015; 52:1015-22. [DOI: 10.1007/s12035-015-9250-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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61
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Hardeland R, Cardinali DP, Brown GM, Pandi-Perumal SR. Melatonin and brain inflammaging. Prog Neurobiol 2015; 127-128:46-63. [DOI: 10.1016/j.pneurobio.2015.02.001] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Revised: 10/27/2014] [Accepted: 02/05/2015] [Indexed: 02/07/2023]
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Kainic Acid-Induced Golgi Complex Fragmentation/Dispersal Shifts the Proteolysis of Reelin in Primary Rat Neuronal Cells: An In Vitro Model of Early Stage Epilepsy. Mol Neurobiol 2015; 53:1874-1883. [PMID: 25790952 PMCID: PMC4577368 DOI: 10.1007/s12035-015-9126-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 02/22/2015] [Indexed: 12/19/2022]
Abstract
The endoplasmic reticulum-lysosome-Golgi network plays an important role in Reelin glycosylation and its proteolytic processing. Golgi complex fragmentation is associated with the separation of Reelin from this network. Kainic acid (KA) is an excitotoxic agent commonly used to induce epilepsy in rodents. The relationship between KA-induced neuronal damage and Golgi complex fragmentation has not been investigated, leaving a major gap in our understanding of the molecular mechanism underlying the development of pathophysiology in epilepsy. We cultured primary rat cortical neurons eitherin ambient condition (control) or treated with a range of KA doses to reveal whether Golgi complex fragmentation impaired neuronal function. The half-life maximal inhibitory concentration (IC50) value of KA was detected to be approximately 5 μM, whereby at these concentrations, KA impaired neuronal viability, which was closely associated with initial Golgi complex fragmentation and subsequent reduction in both the expression and glycosylation patterns of Reelin. These findings implicate that Golgi complex fragmentation and Reelin dysfunction are key contributors to neuronal cell death in the early stage of epilepsy pathophysiology, thereby representing as novel disease biomarkers, as well as potent therapeutic targets for epilepsy.
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63
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Teng YC, Jeng CJ, Huang HJ, Lin AMY. Role of autophagy in arsenite-induced neurotoxicity: The involvement of α-synuclein. Toxicol Lett 2015; 233:239-45. [DOI: 10.1016/j.toxlet.2015.01.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 01/26/2015] [Accepted: 01/28/2015] [Indexed: 11/28/2022]
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Corsetti V, Florenzano F, Atlante A, Bobba A, Ciotti MT, Natale F, Della Valle F, Borreca A, Manca A, Meli G, Ferraina C, Feligioni M, D'Aguanno S, Bussani R, Ammassari-Teule M, Nicolin V, Calissano P, Amadoro G. NH2-truncated human tau induces deregulated mitophagy in neurons by aberrant recruitment of Parkin and UCHL-1: implications in Alzheimer's disease. Hum Mol Genet 2015; 24:3058-81. [PMID: 25687137 DOI: 10.1093/hmg/ddv059] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 02/10/2015] [Indexed: 01/26/2023] Open
Abstract
Disarrangement in functions and quality control of mitochondria at synapses are early events in Alzheimer's disease (AD) pathobiology. We reported that a 20-22 kDa NH2-tau fragment mapping between 26 and 230 amino acids of the longest human tau isoform (aka NH2htau): (i) is detectable in cellular and animal AD models, as well in synaptic mitochondria and cerebrospinal fluids (CSF) from human AD subjects; (ii) is neurotoxic in primary hippocampal neurons; (iii) compromises the mitochondrial biology both directly, by inhibiting the ANT-1-dependent ADP/ATP exchange, and indirectly, by impairing their selective autophagic clearance (mitophagy). Here, we show that the extensive Parkin-dependent turnover of mitochondria occurring in NH2htau-expressing post-mitotic neurons plays a pro-death role and that UCHL-1, the cytosolic Ubiquitin-C-terminal hydrolase L1 which directs the physiological remodeling of synapses by controlling ubiquitin homeostasis, critically contributes to mitochondrial and synaptic failure in this in vitro AD model. Pharmacological or genetic suppression of improper mitophagy, either by inhibition of mitochondrial targeting to autophagosomes or by shRNA-mediated silencing of Parkin or UCHL-1 gene expression, restores synaptic and mitochondrial content providing partial but significant protection against the NH2htau-induced neuronal death. Moreover, in mitochondria from human AD synapses, the endogenous NH2htau is stably associated with Parkin and with UCHL-1. Taken together, our studies show a causative link between the excessive mitochondrial turnover and the NH2htau-induced in vitro neuronal death, suggesting that pathogenetic tau truncation may contribute to synaptic deterioration in AD by aberrant recruitment of Parkin and UCHL-1 to mitochondria making them more prone to detrimental autophagic clearance.
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Affiliation(s)
- V Corsetti
- Institute of Translational Pharmacology (IFT) - National Research Council (CNR), Via Fosso del Cavaliere 100-00133, Rome, Italy
| | - F Florenzano
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - A Atlante
- Institute of Biomembranes and Bioenergetics (IBBE)-CNR, Via Amendola 165/A, 70126 Bari, Italy
| | - A Bobba
- Institute of Biomembranes and Bioenergetics (IBBE)-CNR, Via Amendola 165/A, 70126 Bari, Italy
| | - M T Ciotti
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - F Natale
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - F Della Valle
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - A Borreca
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - A Manca
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - G Meli
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - C Ferraina
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - M Feligioni
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - S D'Aguanno
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - R Bussani
- UCO Pathological Anatomy and Histopathology Unit, Cattinara Hospital Strada di Fiume 447, 34149 Trieste, Italy and
| | - M Ammassari-Teule
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - V Nicolin
- Department of Medical, Surgical and Health Science, University of Trieste, Strada di Fiume 449, 34149 Trieste, Italy
| | - P Calissano
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - G Amadoro
- Institute of Translational Pharmacology (IFT) - National Research Council (CNR), Via Fosso del Cavaliere 100-00133, Rome, Italy European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
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Yürüker V, Nazıroğlu M, Şenol N. Reduction in traumatic brain injury-induced oxidative stress, apoptosis, and calcium entry in rat hippocampus by melatonin: Possible involvement of TRPM2 channels. Metab Brain Dis 2015; 30:223-31. [PMID: 25339252 DOI: 10.1007/s11011-014-9623-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 10/12/2014] [Indexed: 11/26/2022]
Abstract
Melatonin, which is a very effective reactive oxygen species (ROS) scavenger, acts through a direct reaction with free radicals. Ca(2+) entry induced by traumatic brain injury (TBI) has deleterious effects on human hippocampal function. TRPM2 is a Ca(2+) permeable non-selective channel in hippocampal neurons, and its activation of during oxidative stress has been linked to cell death. Despite the importance of oxidative stress in TBI, its role in apoptosis and Ca(2+) entry in TBI is poorly understood. Therefore, we tested the effects of melatonin on apoptosis, oxidative stress, and Ca(2+) entry through the TRPM2 channel in the hippocampal neurons of TBI-induced rats. Thirty-two rats were divided into the following four groups: control, melatonin, TBI, and TBI + melatonin groups. Melatonin (5 mg/kg body weight) was intraperitoneally given to animals in the melatonin group and the TBI + melatonin group after 1 h of brain trauma. Hippocampal neurons were freshly isolated from the four groups, incubated with a nonspecific TRPM2 blocker (2-aminoethyl diphenylborinate, 2-APB), and then stimulated with cumene hydroperoxide. Apoptosis, caspase-3, caspase-9, intracellular ROS production, mitochondrial membrane depolarization and intracellular free Ca(2+) ([Ca(2+)]i) values were high in the TBI group, and low in the TBI + melatonin group. The [Ca(2+)]i concentration was decreased in the four groups by 2-APB. In our TBI experimental model, TRPM2 channels were involved in Ca(2+) entry-induced neuronal death, and the negative modulation of the activity of this channel by melatonin pretreatment may account for the neuroprotective activity of TRPM2 channels against oxidative stress, apoptosis, and Ca(2+) entry.
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Affiliation(s)
- Vehbi Yürüker
- Department of Neurosurgery, Faculty of Medicine, University of SuleymanDemirel, Isparta, Turkey
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Trivedi P, Jena G, Tikoo K, Kumar V. Melatonin modulated autophagy and Nrf2 signaling pathways in mice with colitis-associated colon carcinogenesis. Mol Carcinog 2015; 55:255-67. [DOI: 10.1002/mc.22274] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 11/15/2014] [Accepted: 11/26/2014] [Indexed: 01/07/2023]
Affiliation(s)
- P.P. Trivedi
- Facility for Risk Assessment and Intervention Studies; Department of Pharmacology and Toxicology; National Institute of Pharmaceutical Education and Research; Punjab India
| | - G.B. Jena
- Facility for Risk Assessment and Intervention Studies; Department of Pharmacology and Toxicology; National Institute of Pharmaceutical Education and Research; Punjab India
| | - K.B. Tikoo
- Laboratory of Chromatin Biology; Department of Pharmacology and Toxicology; National Institute of Pharmaceutical Education and Research; Punjab India
| | - V. Kumar
- Icon Analytical Equipment Pvt Ltd; Delhi India
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67
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Galano A, Medina ME, Tan DX, Reiter RJ. Melatonin and its metabolites as copper chelating agents and their role in inhibiting oxidative stress: a physicochemical analysis. J Pineal Res 2015; 58:107-16. [PMID: 25424557 DOI: 10.1111/jpi.12196] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 11/21/2014] [Indexed: 12/27/2022]
Abstract
The copper sequestering ability of melatonin and its metabolites cyclic 3-hydroxymelatonin (3OHM), N(1) -acetyl-N(2) -formyl-5-methoxykynuramine (AFMK), and N(1) -acetyl-5-methoxykynuramine (AMK) was investigated within the frame of the Density Functional Theory. It was demonstrated that these compounds are capable of chelating copper ions, yielding stable complexes. The most likely chelation sites were identified. Two different mechanisms were modeled, the direct-chelation mechanism (DCM) and the coupled-deprotonation-chelation mechanism (CDCM). It is proposed that, under physiological conditions, CDCM would be the main chelation route for Cu(II). It was found that melatonin and its metabolites fully inhibited the oxidative stress induced by Cu(II)-ascorbate mixtures, via Cu(II) chelation. In the same way, melatonin, AFMK, and 3OHM also prevented the first step of the Haber-Weiss reaction, consequently turning off the ˙OH production via the Fenton reaction. Therefore, it is proposed that, in addition to the previously reported free radical scavenging cascade, melatonin is also involved in a concurrent 'chelating cascade', thereby contributing to a reduction in oxidative stress. 3OHM was identified as the most efficient of the studied compounds for that purpose, supporting the important role of this metabolite in the beneficial effects of melatonin against oxidative stress.
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Affiliation(s)
- Annia Galano
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, México, D. F, México
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68
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Fu L, Yu Z, Chen YH, Xia MZ, Wang H, Zhang C, Tao FB, Xu DX. Orally administered melatonin prevents lipopolysaccharide-induced neural tube defects in mice. PLoS One 2014; 9:e113763. [PMID: 25420102 PMCID: PMC4242665 DOI: 10.1371/journal.pone.0113763] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 10/29/2014] [Indexed: 01/06/2023] Open
Abstract
Lipopolysaccharide (LPS) has been associated with adverse pregnant outcomes, including fetal demise, intra-uterine growth restriction (IUGR), neural tube defects (NTDs) and preterm delivery in rodent animals. Previous studies demonstrated that melatonin protected against LPS-induced fetal demise, IUGR and preterm delivery. The aim of the present study was to investigate the effects of melatonin on LPS-induced NTDs. All pregnant mice except controls were intraperitoneally injected with LPS (25 µg/kg) daily from gestational day (GD)8 to GD12. Some pregnant mice were orally administered with melatonin (MT, 50 mg/kg) before each LPS injection. A five-day LPS injection resulted in 27.5% of fetuses with anencephaly, exencephaly or encephalomeningocele. Additional experiment showed that maternal LPS exposure significantly down-regulated placental proton-coupled folate transporter (pcft) and disturbed folate transport from maternal circulation through the placentas into the fetus. Interestingly, melatonin significantly attenuated LPS-induced down-regulation of placental pcft. Moreover, melatonin markedly improved the transport of folate from maternal circulation through the placentas into the fetus. Correspondingly, orally administered melatonin reduced the incidence of LPS-induced anencephaly, exencephaly or encephalomeningocele. Taken together, these results suggest that orally administered melatonin prevents LPS-induced NTDs through alleviating LPS-induced disturbance of folate transport from maternal circulation through the placenta into the fetus.
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Affiliation(s)
- Lin Fu
- Department of Toxicology, Anhui Medical University, Hefei, China
- Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China
| | - Zhen Yu
- Department of Toxicology, Anhui Medical University, Hefei, China
| | - Yuan-Hua Chen
- Department of Toxicology, Anhui Medical University, Hefei, China
- Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China
| | - Mi-Zhen Xia
- School of Life Science, Anhui Medical University, Hefei, China
| | - Hua Wang
- Department of Toxicology, Anhui Medical University, Hefei, China
- Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China
| | - Cheng Zhang
- Department of Toxicology, Anhui Medical University, Hefei, China
| | - Fang-Biao Tao
- Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China
- * E-mail: (FBT); (DXX)
| | - De-Xiang Xu
- Department of Toxicology, Anhui Medical University, Hefei, China
- Anhui Provincial Key Laboratory of Population Health & Aristogenics, Anhui Medical University, Hefei, China
- * E-mail: (FBT); (DXX)
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Sharma S, Sarkar J, Haldar C, Sinha S. Melatonin Reverses Fas, E2F-1 and Endoplasmic Reticulum Stress Mediated Apoptosis and Dysregulation of Autophagy Induced by the Herbicide Atrazine in Murine Splenocytes. PLoS One 2014; 9:e108602. [PMID: 25259610 PMCID: PMC4178181 DOI: 10.1371/journal.pone.0108602] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/01/2014] [Indexed: 12/25/2022] Open
Abstract
Exposure to the herbicide Atrazine (ATR) can cause immunotoxicity, apart from other adverse consequences for animal and human health. We aimed at elucidating the apoptotic mechanisms involved in immunotoxicity of ATR and their attenuation by Melatonin (MEL). Young Swiss mice were divided into control, ATR and MEL+ATR groups based on daily (x14) intraperitoneal administration of the vehicle (normal saline), ATR (100 mg/kg body weight) and MEL (20 mg/kg body weight) with ATR. Isolated splenocytes were processed for detection of apoptosis by Annexin V-FITC and TUNEL assays, and endoplasmic reticulum (ER) stress by immunostaining. Key proteins involved in apoptosis, ER stress and autophagy were quantified by immunoblotting. ATR treatment resulted in Fas-mediated activation of caspases 8 and 3 and inactivation of PARP1 which were inhibited significantly by co-treatment with MEL. MEL also attenuated the ATR-induced, p53 independent mitochondrial apoptosis through upregulation of E2F-1 and PUMA and suppression of their downstream target Bax. An excessive ER stress triggered by ATR through overexpression of ATF-6α, spliced XBP-1, CREB-2 and GADD153 signals was reversed by MEL. MEL also reversed the ATR-induced impairment of autophagy which was indicated by a decline in BECN-1, along with significant enhancement in LC3B-II and p62 expressions. Induction of mitochondrial apoptosis, ER stress and autophagy dysregulation provide a new insight into the mechanism of ATR immunotoxicity. The cytoprotective role of MEL, on the other hand, was defined by attenuation of ER stress, Fas-mediated and p53 independent mitochondria-mediated apoptosis as well as autophagy signals.
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Affiliation(s)
- Shweta Sharma
- Biochemistry Division, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, India
- * E-mail:
| | - Jayanta Sarkar
- Biochemistry Division, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research, New Delhi, India
| | - Chandana Haldar
- Department of Zoology, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Sudhir Sinha
- Biochemistry Division, CSIR-Central Drug Research Institute, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research, New Delhi, India
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Jenwitheesuk A, Nopparat C, Mukda S, Wongchitrat P, Govitrapong P. Melatonin regulates aging and neurodegeneration through energy metabolism, epigenetics, autophagy and circadian rhythm pathways. Int J Mol Sci 2014; 15:16848-84. [PMID: 25247581 PMCID: PMC4200827 DOI: 10.3390/ijms150916848] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/03/2014] [Accepted: 09/12/2014] [Indexed: 12/19/2022] Open
Abstract
Brain aging is linked to certain types of neurodegenerative diseases and identifying new therapeutic targets has become critical. Melatonin, a pineal hormone, associates with molecules and signaling pathways that sense and influence energy metabolism, autophagy, and circadian rhythms, including insulin-like growth factor 1 (IGF-1), Forkhead box O (FoxOs), sirtuins and mammalian target of rapamycin (mTOR) signaling pathways. This review summarizes the current understanding of how melatonin, together with molecular, cellular and systemic energy metabolisms, regulates epigenetic processes in the neurons. This information will lead to a greater understanding of molecular epigenetic aging of the brain and anti-aging mechanisms to increase lifespan under healthy conditions.
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Affiliation(s)
- Anorut Jenwitheesuk
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakornpathom 73170, Thailand.
| | - Chutikorn Nopparat
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakornpathom 73170, Thailand.
| | - Sujira Mukda
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakornpathom 73170, Thailand.
| | - Prapimpun Wongchitrat
- Center for Innovation Development and Technology Transfer, Faculty of Medical Technology, Mahidol University, Salaya, Nakornpathom 73170, Thailand.
| | - Piyarat Govitrapong
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakornpathom 73170, Thailand.
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71
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Joshi N, Biswas J, Nath C, Singh S. Promising Role of Melatonin as Neuroprotectant in Neurodegenerative Pathology. Mol Neurobiol 2014; 52:330-40. [DOI: 10.1007/s12035-014-8865-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 08/14/2014] [Indexed: 12/14/2022]
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Ma P, Yan B, Zeng Q, Liu X, Wu Y, Jiao M, Liu C, Wu J, Yang X. Oral exposure of Kunming mice to diisononyl phthalate induces hepatic and renal tissue injury through the accumulation of ROS. Protective effect of melatonin. Food Chem Toxicol 2014; 68:247-56. [DOI: 10.1016/j.fct.2014.03.027] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Revised: 03/19/2014] [Accepted: 03/22/2014] [Indexed: 11/24/2022]
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San‐Miguel B, Crespo I, Vallejo D, Álvarez M, Prieto J, González‐Gallego J, Tuñón MJ. Melatonin modulates the autophagic response in acute liver failure induced by the rabbit hemorrhagic disease virus. J Pineal Res 2014; 56:313-21. [PMID: 24499270 PMCID: PMC7166588 DOI: 10.1111/jpi.12124] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 01/31/2014] [Indexed: 12/29/2022]
Abstract
Autophagy is an important survival pathway and participates in the host response to infection. Beneficial effects of melatonin have been previously reported in an animal model of acute liver failure (ALF) induced by the rabbit hemorrhagic disease virus (RHDV). This study was aimed to investigate whether melatonin protection against liver injury induced by the RHDV associates to modulation of autophagy. Rabbits were infected with 2 × 10(4) hemagglutination units of a RHDV isolate and received 20 mg/kg melatonin at 0, 12, and 24 hr postinfection. RHDV induced autophagy, with increased expression of beclin-1, ubiquitin-like autophagy-related (Atg)5, Atg12, Atg16L1 and sequestrosome 1 (p62/SQSTM1), protein 1 light chain 3 (LC3) staining, and conversion of LC3-I to autophagosome-associated LC3-II. These effects reached a maximum at 24 hr postinfection, in parallel to extensive colocalization of LC3 and lysosome-associated membrane protein (LAMP)-1. The autophagic response induced by RHDV infection was significantly inhibited by melatonin administration. Melatonin treatment also resulted in decreased immunoreactivity for RHDV viral VP60 antigen and a significantly reduction in RHDV VP60 mRNA levels, oxidized to reduced glutathione ratio (GSSG/GSH), caspase-3 activity, and immunoglobulin-heavy-chain-binding protein (BiP) and CCAAT/enhancer-binding protein homologous protein (CHOP) expression. Results indicate that, in addition to its antioxidant and antiapoptotic effects, and the suppression of ER stress, melatonin induces a decrease in autophagy associated with RHDV infection and inhibits RHDV RNA replication. Results obtained reveal novel molecular pathways accounting for the protective effect of melatonin in this animal model of ALF.
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Affiliation(s)
| | - Irene Crespo
- Institute of Biomedicine (IBIOMED)University of LeónLeónSpain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)Spain
| | - Daniela Vallejo
- Institute of Biomedicine (IBIOMED)University of LeónLeónSpain
| | | | - Jesús Prieto
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)Spain
- Division of Hepatology and Gene TherapyCenter for Applied Medical Research (CIMA)University of NavarraPamplonaSpain
| | - Javier González‐Gallego
- Institute of Biomedicine (IBIOMED)University of LeónLeónSpain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)Spain
| | - María J. Tuñón
- Institute of Biomedicine (IBIOMED)University of LeónLeónSpain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)Spain
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Hung KC, Huang HJ, Lin MW, Lei YP, Lin AMY. Roles of autophagy in MPP+-induced neurotoxicity in vivo: the involvement of mitochondria and α-synuclein aggregation. PLoS One 2014; 9:e91074. [PMID: 24646838 PMCID: PMC3960112 DOI: 10.1371/journal.pone.0091074] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 02/07/2014] [Indexed: 12/18/2022] Open
Abstract
Macroautophagy (also known as autophagy) is an intracellular self-eating mechanism and has been proposed as both neuroprotective and neurodestructive in the central nervous system (CNS) neurodegenerative diseases. In the present study, the role of autophagy involving mitochondria and α-synuclein was investigated in MPP+ (1-methyl-4-phenylpyridinium)-induced oxidative injury in chloral hydrate-anesthetized rats in vivo. The oxidative mechanism underlying MPP+-induced neurotoxicity was identified by elevated lipid peroxidation and heme oxygenase-1 levels, a redox-regulated protein in MPP+-infused substantia nigra (SN). At the same time, MPP+ significantly increased LC3-II levels, a hallmark protein of autophagy. To block MPP+-induced autophagy in rat brain, Atg7siRNA was intranigrally infused 4 d prior to MPP+ infusion. Western blot assay showed that in vivo Atg7siRNA transfection not only reduced Atg7 levels in the MPP+-infused SN but attenuated MPP+-induced elevation in LC3-II levels, activation of caspase 9 and reduction in tyrosine hydroxylase levels, indicating that autophagy is pro-death. The immunostaining study demonstrated co-localization of LC3 and succinate dehydrogenase (a mitochondrial complex II) as well as LC3 and α-synuclein, suggesting that autophagy may engulf mitochondria and α-synuclein. Indeed, in vivo Atg7siRNA transfection mitigated MPP+-induced reduction in cytochrome c oxidase. In addition, MPP+-induced autophagy differentially altered the α-synuclein aggregates in the infused SN. In conclusion, autophagy plays a prodeath role in the MPP+-induced oxidative injury by sequestering mitochondria in the rat brain. Moreover, our data suggest that the benefits of autophagy depend on the levels of α-synuclein aggregates in the nigrostriatal dopaminergic system of the rat brain.
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Affiliation(s)
- Kai-Chih Hung
- Department of Physiology, National Yang-Ming University, Taipei, Taiwan
| | - Hui-Ju Huang
- Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Ming-Wei Lin
- Institute of Public Health, National Yang-Ming University, Taipei, Taiwan
| | - Yen-Ping Lei
- Department of Nursing, National Yang-Ming University, Taipei, Taiwan
| | - Anya Maan-yuh Lin
- Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan
- Department of Pharmacology, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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Ginet V, Spiehlmann A, Rummel C, Rudinskiy N, Grishchuk Y, Luthi-Carter R, Clarke PGH, Truttmann AC, Puyal J. Involvement of autophagy in hypoxic-excitotoxic neuronal death. Autophagy 2014; 10:846-60. [PMID: 24674959 DOI: 10.4161/auto.28264] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Neuronal autophagy is increased in numerous excitotoxic conditions including neonatal cerebral hypoxia-ischemia (HI). However, the role of this HI-induced autophagy remains unclear. To clarify this role we established an in vitro model of excitotoxicity combining kainate treatment (Ka, 30 µM) with hypoxia (Hx, 6% oxygen) in primary neuron cultures. KaHx rapidly induced excitotoxic death that was completely prevented by MK801 or EGTA. KaHx also stimulated neuronal autophagic flux as shown by a rise in autophagosome number (increased levels of LC3-II and punctate LC3 labeling) accompanied by increases in lysosomal abundance and activity (increased SQSTM1/p62 degradation, and increased LC3-II levels in the presence of lysosomal inhibitors) and fusion (shown using an RFP-GFP-LC3 reporter). To determine the role of the enhanced autophagy we applied either pharmacological autophagy inhibitors (3-methyladenine or pepstatinA/E64) or lentiviral vectors delivering shRNAs targeting Becn1 or Atg7. Both strategies reduced KaHx-induced neuronal death. A prodeath role of autophagy was also confirmed by the enhanced toxicity of KaHx in cultures overexpressing BECN1 or ATG7. Finally, in vivo inhibition of autophagy by intrastriatal injection of a lentiviral vector expressing a Becn1-targeting shRNA increased the volume of intact striatum in a rat model of severe neonatal cerebral HI. These results clearly show a death-mediating role of autophagy in hypoxic-excitotoxic conditions and suggest that inhibition of autophagy should be considered as a neuroprotective strategy in HI brain injuries.
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Affiliation(s)
- Vanessa Ginet
- Department of Fundamental Neurosciences; Faculty of Biology and Medicine; University of Lausanne; Lausanne, Switzerland
| | - Amélie Spiehlmann
- Department of Fundamental Neurosciences; Faculty of Biology and Medicine; University of Lausanne; Lausanne, Switzerland
| | - Coralie Rummel
- Department of Fundamental Neurosciences; Faculty of Biology and Medicine; University of Lausanne; Lausanne, Switzerland
| | - Nikita Rudinskiy
- Brain Mind Institute; École Polytechnique Fédérale de Lausanne; Lausanne, Switzerland
| | - Yulia Grishchuk
- Department of Fundamental Neurosciences; Faculty of Biology and Medicine; University of Lausanne; Lausanne, Switzerland
| | - Ruth Luthi-Carter
- Brain Mind Institute; École Polytechnique Fédérale de Lausanne; Lausanne, Switzerland
| | - Peter G H Clarke
- Department of Fundamental Neurosciences; Faculty of Biology and Medicine; University of Lausanne; Lausanne, Switzerland
| | - Anita C Truttmann
- Clinic of Neonatology; Department of Pediatrics and Pediatric Surgery; Lausanne University Hospital and University of Lausanne; Lausanne, Switzerland
| | - Julien Puyal
- Department of Fundamental Neurosciences; Faculty of Biology and Medicine; University of Lausanne; Lausanne, Switzerland; Clinic of Neonatology; Department of Pediatrics and Pediatric Surgery; Lausanne University Hospital and University of Lausanne; Lausanne, Switzerland
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76
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Galano A, Tan DX, Reiter RJ. Cyclic 3-hydroxymelatonin, a key metabolite enhancing the peroxyl radical scavenging activity of melatonin. RSC Adv 2014. [DOI: 10.1039/c3ra44604b] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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77
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Kim SJ, Lee SR. Protective effect of melatonin against transient global cerebral ischemia-induced neuronal cell damage via inhibition of matrix metalloproteinase-9. Life Sci 2013; 94:8-16. [PMID: 24269215 DOI: 10.1016/j.lfs.2013.11.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 11/09/2013] [Accepted: 11/09/2013] [Indexed: 11/26/2022]
Abstract
AIMS Melatonin possesses various pharmacological effects including neuroprotective effects against brain ischemia. Post-ischemic increases in matrix metalloproteinase-9 (MMP-9) expression and activity mainly contribute to neuronal damage by degradation of the extracellular matrix. This study was designed to examine whether melatonin has a neuroprotective effect and an influence on MMP-9 in transient global brain ischemia. MAIN METHODS Mice were subjected to 20 min of global brain ischemia and sacrificed 72h later. Melatonin (30 mg/kg) was administered 30 min before and 2h after ischemia as well as once daily until sacrifice. KEY FINDINGS Hippocampal pyramidal cell damage after ischemia was significantly decreased by melatonin. As observed by zymography, melatonin inhibited the increase of MMP-9 activity after ischemia. In the brain sections, the increased gelatinase activity was mainly observed in the hippocampus after ischemia and melatonin also reduced gelatinase activity. The laminin and NeuN expression levels were reduced in the hippocampal CA1 and CA2 regions after ischemia, and melatonin reduced laminin degradation and neuronal loss. A TUNEL assay demonstrated that there were TUNEL-positive cells in the hippocampus and the number of TUNEL-positive cells was significantly decreased by melatonin. There was no difference in the ischemia-induced hippocampal neuronal damage between the vehicle- and melatonin-treated groups of MMP-9 knock-out mice. SIGNIFICANCE These data demonstrate that melatonin suppressed the occurrence of neuronal injury, which might be partly due to its inhibitory effects on MMP-9 in addition to its anti-oxidative effects. MMP-9 may be an important key target of melatonin in neuroprotection against global ischemia.
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Affiliation(s)
- Su-Jin Kim
- Department of Anesthesiology, College of Medicine, Dongguk University, Gyeongju, South Korea; Department of Pharmacology, School of Medicine and Brain Research Institute, Keimyung University, Daegu 704-701, South Korea
| | - Seong-Ryong Lee
- Department of Pharmacology, School of Medicine and Brain Research Institute, Keimyung University, Daegu 704-701, South Korea.
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78
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Hardeland R. Melatonin and the theories of aging: a critical appraisal of melatonin's role in antiaging mechanisms. J Pineal Res 2013; 55:325-56. [PMID: 24112071 DOI: 10.1111/jpi.12090] [Citation(s) in RCA: 189] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 08/23/2013] [Indexed: 02/06/2023]
Abstract
The classic theories of aging such as the free radical theory, including its mitochondria-related versions, have largely focused on a few specific processes of senescence. Meanwhile, numerous interconnections have become apparent between age-dependent changes previously thought to proceed more or less independently. Increased damage by free radicals is not only linked to impairments of mitochondrial function, but also to inflammaging as it occurs during immune remodeling and by release of proinflammatory cytokines from mitotically arrested, DNA-damaged cells that exhibit the senescence-associated secretory phenotype (SASP). Among other effects, SASP can cause mutations in stem cells that reduce the capacity for tissue regeneration or, in worst case, lead to cancer stem cells. Oxidative stress has also been shown to promote telomere attrition. Moreover, damage by free radicals is connected to impaired circadian rhythmicity. Another nexus exists between cellular oscillators and metabolic sensing, in particular to the aging-suppressor SIRT1, which acts as an accessory clock protein. Melatonin, being a highly pleiotropic regulator molecule, interacts directly or indirectly with all the processes mentioned. These influences are critically reviewed, with emphasis on data from aged organisms and senescence-accelerated animals. The sometimes-controversial findings obtained either in a nongerontological context or in comparisons of tumor with nontumor cells are discussed in light of evidence obtained in senescent organisms. Although, in mammals, lifetime extension by melatonin has been rarely documented in a fully conclusive way, a support of healthy aging has been observed in rodents and is highly likely in humans.
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Affiliation(s)
- Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Göttingen, Göttingen, Germany
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Atanasova M, Petkova Z, Pechlivanova D, Dragomirova P, Blazhev A, Tchekalarova J. Strain-dependent effects of long-term treatment with melatonin on kainic acid-induced status epilepticus, oxidative stress and the expression of heat shock proteins. Pharmacol Biochem Behav 2013; 111:44-50. [DOI: 10.1016/j.pbb.2013.08.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/10/2013] [Accepted: 08/14/2013] [Indexed: 11/28/2022]
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81
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Sae-Teaw M, Johns J, Johns NP, Subongkot S. Serum melatonin levels and antioxidant capacities after consumption of pineapple, orange, or banana by healthy male volunteers. J Pineal Res 2013; 55:58-64. [PMID: 23137025 DOI: 10.1111/jpi.12025] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 09/28/2012] [Indexed: 01/26/2023]
Abstract
Melatonin is a naturally occurring molecule biosynthesized by the pineal gland of vertebrates; it also has been identified in many plants. It is considered an important antioxidant and may retard the development of some neurodegenerative diseases and cancer. Previous studies in humans have measured melatonin metabolites in urine and have indicated that melatonin-containing foods may provide dietary melatonin. This study tested whether the consumption of fruits or fruit juice containing melatonin would influence the serum melatonin concentration and antioxidant status. In this crossover study, 12 healthy male volunteers took either juice extracted from one kilogram of orange or pineapple or two whole bananas, with a 1-wk washout period between the fruit or fruit juices. An enzyme-linked immunosorbent (ELISA) assay was used to determine the serum melatonin concentration. Serum antioxidant capacity was determined by ferric reducing antioxidant power (FRAP) assay and oxygen radical antioxidant capacity (ORAC) assay. The highest serum melatonin concentration was observed at 120 min after fruit consumption, and compared with before consumption levels, their values were significantly increased for pineapple (146 versus 48 pg/mL P = 0.002), orange (151 versus 40 pg/mL, P = 0.005), and banana (140 versus 32 pg/mL, P = 0.008), respectively. Serum antioxidant capacity following fruit consumption also significantly increased in both the FRAP (7-14% increase, P ≤ 0.004) and ORAC (6-9% increase, P = 0.002) assays. Both the serum FRAP and ORAC values strongly correlated with serum melatonin concentration for all three fruits. These findings suggest that tropical fruit consumption increases the serum melatonin concentrations and also raises the antioxidant capacity in the serum of healthy volunteers in proportion to serum melatonin levels.
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Affiliation(s)
- Manit Sae-Teaw
- Faculty of Pharmaceutical Sciences, Ubon Ratchathani University, Ubon Ratchathani, Thailand
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Lima WR, Holder AA, Garcia CRS. Melatonin signaling and its modulation of PfNF-YB transcription factor expression in Plasmodium falciparum. Int J Mol Sci 2013; 14:13704-18. [PMID: 23839089 PMCID: PMC3742212 DOI: 10.3390/ijms140713704] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 06/23/2013] [Accepted: 06/25/2013] [Indexed: 12/15/2022] Open
Abstract
Malaria is one of the most severe tropical infectious diseases. More than 220 million people around the world have a clinical malaria infection and about one million die because of Plasmodium annually. This parasitic pathogen replicates efficiently in its human host making it difficult to eradicate. It is transmitted by mosquito vectors and so far mosquito control programs have not effectively eliminated this transmission. Because of malaria's enormous health and economic impact and the need to develop new control and eventual elimination strategies, a big research effort has been made to better understand the biology of this parasite and its interactions with its vertebrate host. Determination of the genome sequence and organization, the elucidation of the role of key proteins, and cell signaling studies have helped to develop an understanding of the molecular mechanisms that provide the parasite's versatility. The parasite can sense its environment and adapt to benefit its survival, indeed this is essential for it to complete its life cycle. For many years we have studied how the Plasmodium parasite is able to sense melatonin. In this review we discuss the melatonin signaling pathway and its role in the control of Plasmodium replication and development.
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Affiliation(s)
- Wânia Rezende Lima
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo 05508900, Brazil; E-Mail:
| | - Anthony A. Holder
- Division of Parasitology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK; E-Mail:
| | - Célia R. S. Garcia
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo 05508900, Brazil; E-Mail:
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Kaur C, Sivakumar V, Robinson R, Foulds WS, Luu CD, Ling EA. Neuroprotective effect of melatonin against hypoxia-induced retinal ganglion cell death in neonatal rats. J Pineal Res 2013; 54:190-206. [PMID: 23113620 DOI: 10.1111/jpi.12016] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 09/04/2012] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to determine whether melatonin treatment would mitigate retinal ganglion cell (RGC) death in the developing retina following a hypoxic insult. Lipid peroxidation (LPO), glutathione (GSH), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) concentrations, expression of vascular endothelial growth factor receptors, Flt-1 and Flk-1, release of cytochrome c from mitochondria, and caspase-3 expression were examined in the retinas of 1-day-old rats at 3 hr to 14 days after a hypoxic exposure. The mRNA and protein expression of Flt-1 and Flk-1 and the tissue concentration of LPO, TNF-α, and IL-1β were upregulated significantly after the hypoxic exposure, whereas the content of GSH was decreased significantly. RGC cultures also showed increased LPO and decreased GSH levels after hypoxic exposure but these effects were reversed in cells treated with melatonin. TNF-α and IL-1β expression was specifically located on microglial cells, whereas Flt-1 and Flk-1 was limited to RGCs as confirmed by double immunofluorescence labeling. Cultures of hypoxic microglial cells treated with melatonin showed a significant reduction in the release of these cytokines as compared to untreated hypoxic cells. Hypoxia induced increase in the cytosolic cytochrome c and caspase-3 in RGCs was attenuated with melatonin treatment. The results suggest that, in hypoxic injuries, melatonin is neuroprotective to RGCs in the developing retina through its antioxidative, anti-inflammatory, and anti-apoptotic effects. Melatonin suppressed Flt-1 and Flk-1 expression in retinal blood vessels, which may result in reduced retinal vascular permeability and it also preserved mitochondrial function as shown by a reduction in cytochrome c leakage into the cytosol. The results may have therapeutic implications for the management of retinopathy of prematurity.
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Affiliation(s)
- Charanjit Kaur
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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Melatonin attenuates scopolamine-induced memory/synaptic disorder by rescuing EPACs/miR-124/Egr1 pathway. Mol Neurobiol 2012; 47:373-81. [PMID: 23054680 DOI: 10.1007/s12035-012-8355-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 09/25/2012] [Indexed: 10/27/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent type of dementia in elderly people. There are decreased melatonin levels in the serum of AD patients, and melatonin supplements are able to reverse AD pathology and memory deficits in many animal experiments and clinical trials. However, the underlying mechanism regarding how melatonin rescues the AD-like memory/synaptic disorder remains unknown. Here, we use the Morris water maze, step-down inhibitory avoidance task, in vivo long-term potentiation recording, and Golgi staining and report that intraperitoneal injection of melatonin (1 mg/kg/day) for 14 days in rats effectively reverses the memory and synaptic impairment in scopolamine-induced amnesia, a well-recognized dementia animal model. Using real-time polymerase chain reaction and western blotting experiments, we further determined that melatonin rescues the EPACs/miR-124/Egr1 signal pathway, which is important in learning and memory, as reported recently. Our studies provide a novel underlying epigenetic mechanism for melatonin to attenuate the synaptic disorder and could benefit drug discovery in neurodegenerative diseases.
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