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Boutin JA, Hamon de Almeida V, Coussay N, Legros C, Ferry G, Reybier K. Melatonin facts: Melatonin lacks immuno-inflammation boosting capacities at the molecular and cellular levels. Biochimie 2024; 222:195-202. [PMID: 38508513 DOI: 10.1016/j.biochi.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/03/2024] [Accepted: 03/15/2024] [Indexed: 03/22/2024]
Abstract
Among the properties melatonin is claimed to possess, are the immuno-inflammation inductive capacities that would be responsible of some of the paramount of activities melatonin is reported to have in most of the human pathological conditions. In the present paper, we measured the effect of melatonin on established cellular models of immuno-inflammation, and found none. The discrepancies are discussed, especially because those properties are reported at pharmacological concentration (1 μM and beyond) at which the melatonin receptors are desensitized by internalization, leading to putative non-receptor-dependent mechanism of action.
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Affiliation(s)
- Jean A Boutin
- Laboratory of Neuroendocrine Endocrine and Germinal Differentiation and Communication (NorDiC), University Rouen Normandie, INSERM, NorDiC UMR 1239, F-76000, Rouen, France.
| | | | | | | | | | - Karine Reybier
- Pharma-Dev UMR 152, Université de Toulouse, IRD, UT3, Toulouse, France
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2
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Reiter RJ, Sharma R, Tan DX, Chuffa LGDA, da Silva DGH, Slominski AT, Steinbrink K, Kleszczynski K. Dual sources of melatonin and evidence for different primary functions. Front Endocrinol (Lausanne) 2024; 15:1414463. [PMID: 38808108 PMCID: PMC11130361 DOI: 10.3389/fendo.2024.1414463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2024] [Accepted: 04/30/2024] [Indexed: 05/30/2024] Open
Abstract
This article discusses data showing that mammals, including humans, have two sources of melatonin that exhibit different functions. The best-known source of melatonin, herein referred to as Source #1, is the pineal gland. In this organ, melatonin production is circadian with maximal synthesis and release into the blood and cerebrospinal fluid occurring during the night. Of the total amount of melatonin produced in mammals, we speculate that less than 5% is synthesized by the pineal gland. The melatonin rhythm has the primary function of influencing the circadian clock at the level of the suprachiasmatic nucleus (the CSF melatonin) and the clockwork in all peripheral organs (the blood melatonin) via receptor-mediated actions. A second source of melatonin (Source # 2) is from multiple tissues throughout the body, probably being synthesized in the mitochondria of these cells. This constitutes the bulk of the melatonin produced in mammals and is concerned with metabolic regulation. This review emphasizes the action of melatonin from peripheral sources in determining re-dox homeostasis, but it has other critical metabolic effects as well. Extrapineal melatonin synthesis does not exhibit a circadian rhythm and it is not released into the blood but acts locally in its cell of origin and possibly in a paracrine matter on adjacent cells. The factors that control/influence melatonin synthesis at extrapineal sites are unknown. We propose that the concentration of melatonin in these cells is determined by the subcellular redox state and that melatonin synthesis may be inducible under stressful conditions as in plant cells.
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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, United States
| | - Ramaswamy Sharma
- Applied Biomedical Sciences, University of the Incarnate Word, School of Osteopathic Medicine, San Antonio, TX, United States
| | - Dun-Xian Tan
- Department of Cell Systems and Anatomy, UT Health San Antonio, Long School of Medicine, San Antonio TX, United States
| | - Luiz Gustavo de Almieda Chuffa
- Departamento de Biologia Estrutural e Funcional, Setor de Anatomia - Instituto de Biociências, IBB/UNESP, Botucatu, São Paulo, Brazil
| | - Danilo Grunig Humberto da Silva
- Department of Biology, Universidade Estadual Paulista (UNESP), São Paulo, Brazil
- Department of Biology, Universidade Federal de Mato Grosso Do Sul, Três Lagoas, Mato Grosso Do Sul, Brazil
| | - Andrzej T. Slominski
- US and Pathology Laboratory Service, Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL, United States
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Bernatoniene J, Sciupokas A, Kopustinskiene DM, Petrikonis K. Novel Drug Targets and Emerging Pharmacotherapies in Neuropathic Pain. Pharmaceutics 2023; 15:1799. [PMID: 37513986 PMCID: PMC10384314 DOI: 10.3390/pharmaceutics15071799] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 07/30/2023] Open
Abstract
Neuropathic pain is a debilitating condition characterized by abnormal signaling within the nervous system, resulting in persistent and often intense sensations of pain. It can arise from various causes, including traumatic nerve injury, neuropathy, and certain diseases. We present an overview of current and emerging pharmacotherapies for neuropathic pain, focusing on novel drug targets and potential therapeutic agents. Current pharmacotherapies, including tricyclic antidepressants, gabapentinoids, and serotonin norepinephrine re-uptake inhibitors, are discussed, as are emerging treatments, such as ambroxol, cannabidiol, and N-acetyl-L-cysteine. Additionally, the article highlights the need for further research in this field to identify new targets and develop more effective and targeted therapies for neuropathic pain management.
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Affiliation(s)
- Jurga Bernatoniene
- Department of Drug Technology and Social Pharmacy, Faculty of Pharmacy, Medical Academy, Lithuanian University of Health Sciences, Sukileliu pr. 13, LT-50161 Kaunas, Lithuania
- Institute of Pharmaceutical Technologies, Faculty of Pharmacy, Medical Academy, Lithuanian University of Health Sciences, Sukileliu pr. 13, LT-50161 Kaunas, Lithuania
| | - Arunas Sciupokas
- Pain Clinic, Lithuanian University of Health Sciences Hospital Kauno Klinikos, Eivenių Str. 2, LT-50009 Kaunas, Lithuania
- Department of Neurology, Lithuanian University of Health Sciences, Eivenių Str. 2, LT-50009 Kaunas, Lithuania
| | - Dalia Marija Kopustinskiene
- Institute of Pharmaceutical Technologies, Faculty of Pharmacy, Medical Academy, Lithuanian University of Health Sciences, Sukileliu pr. 13, LT-50161 Kaunas, Lithuania
| | - Kestutis Petrikonis
- Department of Neurology, Lithuanian University of Health Sciences, Eivenių Str. 2, LT-50009 Kaunas, Lithuania
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Boutin JA, Kennaway DJ, Jockers R. Melatonin: Facts, Extrapolations and Clinical Trials. Biomolecules 2023; 13:943. [PMID: 37371523 DOI: 10.3390/biom13060943] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/30/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
Melatonin is a fascinating molecule that has captured the imagination of many scientists since its discovery in 1958. In recent times, the focus has changed from investigating its natural role as a transducer of biological time for physiological systems to hypothesized roles in virtually all clinical conditions. This goes along with the appearance of extensive literature claiming the (generally) positive benefits of high doses of melatonin in animal models and various clinical situations that would not be receptor-mediated. Based on the assumption that melatonin is safe, high doses have been administered to patients, including the elderly and children, in clinical trials. In this review, we critically review the corresponding literature, including the hypotheses that melatonin acts as a scavenger molecule, in particular in mitochondria, by trying not only to contextualize these interests but also by attempting to separate the wheat from the chaff (or the wishful thinking from the facts). We conclude that most claims remain hypotheses and that the experimental evidence used to promote them is limited and sometimes flawed. Our review will hopefully encourage clinical researchers to reflect on what melatonin can and cannot do and help move the field forward on a solid basis.
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Affiliation(s)
- J A Boutin
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, University of Normandy, INSERM U1239, 76000 Rouen, France
| | - D J Kennaway
- Robinson Research Institute and Adelaide School of Medicine, University of Adelaide, Adelaide Health and Medical Science Building, North Terrace, Adelaide, SA 5006, Australia
| | - R Jockers
- Institut Cochin, Université Paris Cité, INSERM, CNRS, 75014 Paris, France
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Duittoz AH, Kenny DA. Review: Early and late determinants of puberty in ruminants and the role of nutrition. Animal 2023; 17 Suppl 1:100812. [PMID: 37567653 DOI: 10.1016/j.animal.2023.100812] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 04/03/2023] [Accepted: 04/06/2023] [Indexed: 08/13/2023] Open
Abstract
This article reviews the scientific literature on puberty with a focus on ruminants and draws inference, where appropriate, from recent findings in transgenic mouse models and human pathology. Early genetic determinants of puberty have been discovered in humans suffering from hypogonadotropic hypogonadism or central precocious puberty. Transgenic mouse models selected on the basis of the causative defective genes helped in discovering the cellular and molecular mechanisms involved. Most of the genes found are involved in the development of neuroendocrine networks during embryo development and early postnatal life. Notwithstanding that the development of neuroendocrine networks takes place early in puberty, a delay or acceleration in the development of Gonadotropin Releasing Hormone (GnRH) neurons has an impact on puberty onset inducing a delay or an advance, respectively. Among the genes discovered in humans and laboratory models, only a few of them displayed polymorphisms associated with advanced sexual maturity, but also marbling, growth traits and callipygian conformation. This could be related to the fact that rather than puberty onset, most research monitored sexual maturity. Sexual maturity occurs after puberty onset and involves factors regulating the maturation of gonads and in the expression of sexual behaviour. The association with growth and metabolic traits is not surprising since nutrition is the major environmental factor that will act on late genetic determinants of puberty onset. However, a recent hypothesis emerged suggesting that it is the postnatal activation of the GnRH neuronal network that induces the acceleration of growth and weight gain. Hence, nutritional factors need the activation of GnRH neurons first before acting on late genetic determinants. Moreover, nutritional factors can also affect the epigenetic landscape of parental gamete's genome with the consequence of specific methylation of genes involved in GnRH neuron development in the embryo. Season is another important regulator of puberty onset in seasonal small ruminants and appears to involve the same mechanisms that are involved in seasonal transition in adults. The social environment is also an underestimated factor affecting puberty onset in domestic ruminants, most research studies focused on olfactory cues, but the genetic basis has not heretofore been adequately tackled by the scientific community. Additionally, there is some evidence to suggest transgenerational effects exist, in that nutritional and social cues to which parents were exposed, could affect the epigenetic landscape of parental gametes resulting in the epigenetic regulation of early genetic determinants of puberty onset in their offspring.
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Affiliation(s)
- A H Duittoz
- UMR 0083 BOA, INRAE, Centre Val de Loire, 37380 Nouzilly, France.
| | - D A Kenny
- Teagasc, Animal & Grassland Research and Innovation Centre, Grange, Dunsany, Co. Meath. C15 PW93, Ireland
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Reiter RJ, Sharma R, Cucielo MS, Tan DX, Rosales-Corral S, Gancitano G, de Almeida Chuffa LG. Brain washing and neural health: role of age, sleep, and the cerebrospinal fluid melatonin rhythm. Cell Mol Life Sci 2023; 80:88. [PMID: 36917314 PMCID: PMC11072793 DOI: 10.1007/s00018-023-04736-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 02/02/2023] [Accepted: 02/24/2023] [Indexed: 03/16/2023]
Abstract
The brain lacks a classic lymphatic drainage system. How it is cleansed of damaged proteins, cellular debris, and molecular by-products has remained a mystery for decades. Recent discoveries have identified a hybrid system that includes cerebrospinal fluid (CSF)-filled perivascular spaces and classic lymph vessels in the dural covering of the brain and spinal cord that functionally cooperate to remove toxic and non-functional trash from the brain. These two components functioning together are referred to as the glymphatic system. We propose that the high levels of melatonin secreted by the pineal gland directly into the CSF play a role in flushing pathological molecules such as amyloid-β peptide (Aβ) from the brain via this network. Melatonin is a sleep-promoting agent, with waste clearance from the CNS being highest especially during slow wave sleep. Melatonin is also a potent and versatile antioxidant that prevents neural accumulation of oxidatively-damaged molecules which contribute to neurological decline. Due to its feedback actions on the suprachiasmatic nucleus, CSF melatonin rhythm functions to maintain optimal circadian rhythmicity, which is also critical for preserving neurocognitive health. Melatonin levels drop dramatically in the frail aged, potentially contributing to neurological failure and dementia. Melatonin supplementation in animal models of Alzheimer's disease (AD) defers Aβ accumulation, enhances its clearance from the CNS, and prolongs animal survival. In AD patients, preliminary data show that melatonin use reduces neurobehavioral signs such as sundowning. Finally, melatonin controls the mitotic activity of neural stem cells in the subventricular zone, suggesting its involvement in neuronal renewal.
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Affiliation(s)
- Russel J Reiter
- Department of Cell Systems and Anatomy, Long School of Medicine, UT Health San Antonio, San Antonio, TX, 78229, USA.
| | - Ramaswamy Sharma
- Department of Cell Systems and Anatomy, Long School of Medicine, UT Health San Antonio, San Antonio, TX, 78229, USA.
| | - Maira Smaniotto Cucielo
- Department of Structural and Functional Biology-IBB/UNESP, Institute of Biosciences of Botucatu, Universidade Estadual Paulista, Botucatu, São Paulo, 18618-689, Brazil
| | | | - Sergio Rosales-Corral
- Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico
| | - Giuseppe Gancitano
- 1st "Tuscania" Paratrooper Regiment, Italian Ministry of Defense, 57127, Leghorn, Italy
| | - Luiz Gustavo de Almeida Chuffa
- Department of Structural and Functional Biology-IBB/UNESP, Institute of Biosciences of Botucatu, Universidade Estadual Paulista, Botucatu, São Paulo, 18618-689, Brazil
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Gancitano G, Reiter RJ. The Multiple Functions of Melatonin: Applications in the Military Setting. Biomedicines 2022; 11:biomedicines11010005. [PMID: 36672513 PMCID: PMC9855431 DOI: 10.3390/biomedicines11010005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/14/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022] Open
Abstract
The aim of this review is to provide the reader with a general overview on the rationale for the use of melatonin by military personnel. This is a technique that is being increasingly employed to manage growing psycho-physical loads. In this context, melatonin, a pleotropic and regulatory molecule, has a potential preventive and therapeutic role in maintaining the operational efficiency of military personnel. In battlefield conditions in particular, the time to treatment after an injury is often a major issue since the injured may not have immediate access to medical care. Any drug that would help to stabilize a wounded individual, especially if it can be immediately administered (e.g., per os) and has a very high safety profile over a large range of doses (as melatonin does) would be an important asset to reduce morbidity and mortality. Melatonin may also play a role in the oscillatory synchronization of the neuro-cardio-respiratory systems and, through its epigenetic action, poses the possibility of restoring the main oscillatory waves of the cardiovascular system, such as the Mayer wave and RSA (respiratory sinus arrhythmia), which, in physiological conditions, result in the oscillation of the heartbeat in synchrony with the breath. In the future, this could be a very promising field of investigation.
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Affiliation(s)
- Giuseppe Gancitano
- 1st Carabinieri Paratrooper Regiment “Tuscania”, Italian Ministry of Defence, 57127 Livorno, Italy
- Correspondence:
| | - Russel J. Reiter
- Department of Cell Systems and Anatomy, UT Health, Long School of Medicine, San Antonio, TX 78229, USA
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Huang J, Li Z, Hu Y, Li Z, Xie Y, Huang H, Chen Q, Chen G, Zhu W, Chen Y, Su W, Chen X, Liang D. Melatonin, an endogenous hormone, modulates Th17 cells via the reactive-oxygen species/TXNIP/HIF-1α axis to alleviate autoimmune uveitis. J Neuroinflammation 2022; 19:124. [PMID: 35624485 PMCID: PMC9145533 DOI: 10.1186/s12974-022-02477-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 05/15/2022] [Indexed: 11/25/2022] Open
Abstract
Background Melatonin, an indoleamine produced by the pineal gland, plays a pivotal role in maintaining circadian rhythm homeostasis. Recently, the strong antioxidant and anti-inflammatory properties of melatonin have attracted attention of researchers. We evaluated the therapeutic efficacy of melatonin in experimental autoimmune uveitis (EAU), which is a representative animal model of human autoimmune uveitis. Methods EAU was induced in mice via immunization with the peptide interphotoreceptor retinoid binding protein 1–20 (IRBP1–20). Melatonin was then administered via intraperitoneal injection to induce protection against EAU. With EAU induction for 14 days, clinical and histopathological scores were graded to evaluate the disease progression. T lymphocytes accumulation and the expression of inflammatory cytokines in the retinas were assessed via flow cytometry and RT-PCR, respectively. T helper 1 (Th1), T helper 17 (Th17), and regulatory T (Treg) cells were detected via flow cytometry for both in vivo and in vitro experiments. Reactive-oxygen species (ROS) from CD4 + T cells was tested via flow cytometry. The expression of thioredoxin-interacting protein (TXNIP) and hypoxia-inducible factor 1 alpha (HIF-1α) proteins were quantified via western blot. Results Melatonin treatment resulted in notable attenuation of ocular inflammation in EAU mice, evidenced by decreasing optic disc edema, few signs of retinal vasculitis, and minimal retinal and choroidal infiltrates. Mechanistic studies revealed that melatonin restricted the proliferation of peripheral Th1 and Th17 cells by suppressing their transcription factors and potentiated Treg cells. In vitro studies corroborated that melatonin restrained the polarization of retina-specific T cells towards Th17 and Th1 cells in addition to enhancing the proportion of Treg cells. Pretreatment of retina-specific T cells with melatonin failed to induce EAU in naïve recipients. Furthermore, the ROS/ TXNIP/ HIF-1α pathway was shown to mediate the therapeutic effect of melatonin in EAU. Conclusions Melatonin regulates autoimmune T cells by restraining effector T cells and facilitating Treg generation, indicating that melatonin could be a hopeful treatment alternative for autoimmune uveitis. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02477-z.
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Affiliation(s)
- Jun Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Zhuang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Yunwei Hu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Zuoyi Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Yanyan Xie
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Haixiang Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Qian Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Guanyu Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Wenjie Zhu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Yuxi Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Wenru Su
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China
| | - Xiaoqing Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China.
| | - Dan Liang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Guangdong Provincial Key Laboratoryof Ophthalmologyand VisualScience, Sun Yat-Sen University, Guangzhou, 510060, China.
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Melatonin in ventricular and subarachnoid cerebrospinal fluid: Its function in the neural glymphatic network and biological significance for neurocognitive health. Biochem Biophys Res Commun 2022; 605:70-81. [DOI: 10.1016/j.bbrc.2022.03.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 12/13/2022]
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Dardente H, Simonneaux V. GnRH and the photoperiodic control of seasonal reproduction: Delegating the task to kisspeptin and RFRP-3. J Neuroendocrinol 2022; 34:e13124. [PMID: 35384117 DOI: 10.1111/jne.13124] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/22/2022] [Accepted: 03/03/2022] [Indexed: 10/18/2022]
Abstract
Synchronization of mammalian breeding activity to the annual change of photoperiod and environmental conditions is of the utmost importance for individual survival and species perpetuation. Subsequent to the early 1960s, when the central role of melatonin in this adaptive process was demonstrated, our comprehension of the mechanisms through which light regulates gonadal activity has increased considerably. The current model for the photoperiodic neuroendocrine system points to pivotal roles for the melatonin-sensitive pars tuberalis (PT) and its seasonally-regulated production of thyroid-stimulating hormone (TSH), as well as for TSH-sensitive hypothalamic tanycytes, radial glia-like cells located in the basal part of the third ventricle. Tanycytes respond to TSH through increased expression of thyroid hormone (TH) deiodinase 2 (Dio2), which leads to heightened production of intrahypothalamic triiodothyronine (T3) during longer days of spring and summer. There is strong evidence that this local, long-day driven, increase in T3 links melatonin input at the PT to gonadotropin-releasing hormone (GnRH) output, to align breeding with the seasons. The mechanism(s) through which T3 impinges upon GnRH remain(s) unclear. However, two distinct neuronal populations of the medio-basal hypothalamus, which express the (Arg)(Phe)-amide peptides kisspeptin and RFamide-related peptide-3, appear to be well-positioned to relay this seasonal T3 message towards GnRH neurons. Here, we summarize our current understanding of the cellular, molecular and neuroendocrine players, which keep track of photoperiod and ultimately govern GnRH output and seasonal breeding.
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Affiliation(s)
- Hugues Dardente
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | - Valérie Simonneaux
- Institute for Cellular and Integrative Neuroscience, University of Strasbourg, Strasbourg, France
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11
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Tang L, Zhang C, Lu L, Tian H, Liu K, Luo D, Qiu Q, Xu GT, Zhang J. Melatonin Maintains Inner Blood-Retinal Barrier by Regulating Microglia via Inhibition of PI3K/Akt/Stat3/NF-κB Signaling Pathways in Experimental Diabetic Retinopathy. Front Immunol 2022; 13:831660. [PMID: 35371022 PMCID: PMC8964465 DOI: 10.3389/fimmu.2022.831660] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 02/11/2022] [Indexed: 12/31/2022] Open
Abstract
Microglial activation and melatonin protection have been reported in diabetic retinopathy (DR). Whether melatonin could regulate microglia to protect the inner blood–retinal barrier (iBRB) remains unknown. In this study, the role of microglia in iBRB breakdown and the mechanisms of melatonin’s regulation on microglia were explored. In diabetic rat retinas, activated microglia proliferated and migrated from the inner retina to the outer retina, accompanied by the obvious morphological changes. Meanwhile, significant leakage of albumin was evidenced at the site of close interaction between activated microglia and the damaged pericytes and endothelial cells. In vitro, inflammation-related cytokines, such as tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), interleukin (IL)-1β, and arginase-1 (Arg-1), were increased significantly in CoCl2-treated BV2 cells. The supernatant derived from CoCl2-treated BV2 cells significantly decreased the cell viability and disrupted the junctional proteins in both pericytes and endothelial cells, resulting in severe leakage. Melatonin suppressed the microglial overactivation, i.e., decreasing the cell number and promoting its anti-inflammatory properties in diabetic rat retinas. Moreover, the leakage of iBRB was alleviated and the pericyte coverage was restored after melatonin treatment. In vitro, when treated with melatonin in CoCl2-treated BV2 cells, the inflammatory factors were decreased, while the anti-inflammatory factors were increased, further reducing the pericyte loss and increasing the tight junctions. Melatonin deactivated microglia via inhibition of PI3K/Akt/Stat3/NF-κB signaling pathways, thus maintaining the integrity of iBRB. The present data support a causal role for activated microglia in iBRB breakdown and highlight the therapeutic potential of melatonin in the treatment of DR by regulating microglia.
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Affiliation(s)
- Lei Tang
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Chaoyang Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.,National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Lixia Lu
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Haibin Tian
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Kun Liu
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.,National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Dawei Luo
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.,National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Qinghua Qiu
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.,National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Guo-Tong Xu
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Jingfa Zhang
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University School of Medicine, Shanghai, China.,National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
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Giannetto C, Rajaei SM, Abdous A, Ostadhasan H, Alagha HE, Faghihi H, Piccione G, Omidi R, Fazio F. Effects of long-term oral administration of melatonin on tear production, intraocular pressure, and tear and serum melatonin concentrations in healthy dogs. J Am Vet Med Assoc 2022; 260:524-529. [PMID: 34986123 DOI: 10.2460/javma.21.03.0114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate the effects of long-term (30-day) oral administration of melatonin on tear production, intraocular pressure (IOP), and concentration of melatonin in the tears and serum of healthy dogs. ANIMALS 20 healthy sexually intact adult male dogs. PROCEDURES 10 dogs were given melatonin (0.3 mg/kg, PO, q 24 h, administered in food at 9 am), and 10 dogs were given a placebo. Tear and serum melatonin concentrations, IOP, and tear production (determined with a Schirmer tear test) were recorded before (baseline) and 30 minutes, 3 hours, and 5 hours after administration of melatonin or the placebo on day 1 and 30 minutes after administration of melatonin or the placebo on days 8, 15, and 30. RESULTS Data collection time had significant effects on tear production, IOP, and tear melatonin concentration but not on serum melatonin concentration. Treatment (melatonin vs placebo) had a significant effect on tear melatonin concentration, but not on tear production, IOP, or serum melatonin concentration; however, tear melatonin concentration was significantly different between groups only 30 minutes after administration on day 1 and not at other times. CLINICAL RELEVANCE In healthy dogs, long-term administration of melatonin at a dosage of 0.3 mg/kg, PO, every 24 hours did not have any clinically important effects on tear production, IOP, or serum or tear melatonin concentrations.
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Affiliation(s)
- Claudia Giannetto
- 1Department of Veterinary Sciences, Polo Universitario Annunziata, University of Messina, Messina, Italy
| | - Seyed Mehdi Rajaei
- 2Ophthalmology Section, Negah Veterinary Centre, Tehran, Iran.,3Department of Clinical Sciences, College of Veterinary Medicine, Karaj Branch, Islamic Azad University, Karaj, Iran
| | - Arman Abdous
- 3Department of Clinical Sciences, College of Veterinary Medicine, Karaj Branch, Islamic Azad University, Karaj, Iran
| | - Hesam Ostadhasan
- 3Department of Clinical Sciences, College of Veterinary Medicine, Karaj Branch, Islamic Azad University, Karaj, Iran
| | - Hannah Emami Alagha
- 3Department of Clinical Sciences, College of Veterinary Medicine, Karaj Branch, Islamic Azad University, Karaj, Iran
| | - Houman Faghihi
- 2Ophthalmology Section, Negah Veterinary Centre, Tehran, Iran
| | - Giuseppe Piccione
- 1Department of Veterinary Sciences, Polo Universitario Annunziata, University of Messina, Messina, Italy
| | - Roghiyeh Omidi
- 4Stem Cell Preparation Unit, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Francesco Fazio
- 1Department of Veterinary Sciences, Polo Universitario Annunziata, University of Messina, Messina, Italy
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13
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Legros C, Boutin JA. Detection of Melatonin in Tissue Samples. Methods Mol Biol 2022; 2550:7-12. [PMID: 36180671 DOI: 10.1007/978-1-0716-2593-4_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Melatonin is present in higher quantity in brain during the night. The variation of its quantity is not only a matter of day/night cycle but also a matter of organ and tissues' sublocalization. It is of the highest importance to be able to precisely measure these quantities, and thus, these variations, particularly to better understand the way melatonin signals its presence and the variation thereof through many putative targets. In this chapter, we detail the way these measures can be performed.
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Affiliation(s)
| | - Jean A Boutin
- PHARMADEV (Pharmacochimie et biologie pour le développement), Faculté de Pharmacie, Toulouse, France.
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14
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Gautier C, Theret I, Lizzo G, Ferry G, Guénin SP, Boutin JA. Why Are We Still Cloning Melatonin Receptors? A Commentary. Methods Mol Biol 2022; 2550:267-281. [PMID: 36180698 DOI: 10.1007/978-1-0716-2593-4_29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Cloning may seem to be a view from the past. The time before software, computers and AI were invented. It seems to us worth discussing these points in view of our favorite target: the melatoninergic system. In a few stances, it might be important to point out that even in the new era of dry science, there is still a need to experiment and to prove at the bench that our in silico assertions are right. Most of the living animals express to some extend the melatonin receptors. Some of these animal genomes were completely or partially sequenced, and it is tempting to extract from this huge information the sequence(s) of our favorite genes (MLT receptors). Then, why bother cloning, as opposed to simply built the gene and express it in a host cell? Because the genetic boundaries of the expressed sequence(s) are not 100% sure. Because the melatonin receptor gene(s) comprise a first exon 25,000 base pair far from the second one and the limits between this Ex1 and In1-as between In1 and Ex2-are subject to changes that might have a huge impact on the biochemical properties of the receptor, once expressed. Because a receptor is a biochemical entity with characteristics that are important for the functioning of this particular pathway, and more generally, for the functioning of life.
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Affiliation(s)
- Célia Gautier
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Isabelle Theret
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Giulia Lizzo
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Gilles Ferry
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Sophie-Pénélope Guénin
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France
| | - Jean A Boutin
- Pôle d'expertise Biotechnologie, Chimie & Biologie, Institut de Recherches Servier, Croissy-sur-Seine, France.
- Pharma-Dev (Pharmacochimie et Biologie pour le Développement), Faculté de Pharmacie, UMR 152, Université de Toulouse, Toulouse, France.
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15
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Rodrigues AC, de M. Camargo LT, Francisco Lopes Y, Sallum LO, Napolitano HB, Camargo AJ. Aqueous solvation study of melatonin using ab initio molecular dynamics. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Shabajee-Alibay P, Bonnaud A, Malpaux B, Delagrange P, Audinot V, Yous S, Boutin JA, Stephan JP, Leprince J, Legros C. A putative new melatonin binding site in sheep brain, MTx: preliminary observations and characteristics. J Pharmacol Exp Ther 2021; 380:JPET-AR-2021-000785. [PMID: 34706966 DOI: 10.1124/jpet.121.000785] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 09/29/2021] [Accepted: 10/22/2021] [Indexed: 11/22/2022] Open
Abstract
In mammals, MT1 and MT2 melatonin receptors are high affinity G protein-coupled receptors and are thought to be involved in the integration of the melatonin signaling throughout the brain and periphery. In the present study, we describe a new melatonin binding site, named MTx, with a peculiar pharmacological profile. This site had a low affinity for 2-[125I]-melatonin in saturation assays in hypothalamus and retina (pKD = 9.13 {plus minus} 0.05, Bmax = 1.12 {plus minus} 0.11 fmol/mg protein and pKD = 8.81 {plus minus} 0.50, Bmax = 7.65 {plus minus} 2.64 fmol/mg protein, respectively) and a very high affinity, in competition assays, for melatonin (pKi = 13.08 {plus minus} 0.18), and other endogenous compounds. Using autoradiography, we showed a preferential localization of the MTx in periventricular areas of the sheep brain, with a density 3 to 8 times higher than those observed for ovine MT1 In addition, using a set of well-characterized ligands, we showed that this site did not correspond to any of the following receptors: MT1, MT2, MT3 , D1, D2, noradrenergic, nor 5-HT2 Based on its affinity for melatonin, MTx did not seem to be implicated in the integration of cerebral melatonin concentration variations since they were saturating for MTx. Nevertheless, it remained of prime importance because of its periventricular distribution, in close contact with the CSF, and its peculiar pharmacological profile responding to both melatoninergic and serotoninergic compounds. Significance Statement Herein a putative new melatonin binding site is described in sheep brain parts in close contact with the 3rd ventricle. The characteristics of the pharmacological profile of this site is different from anything previously reported in the literature. The present work forms the basis of future full pharmacological characterization.
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Affiliation(s)
- Preety Shabajee-Alibay
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, UNIROUEN, INSERM 1239, France
| | | | - Benoit Malpaux
- UMR Physiologie de la Reproduction et des Comportements, INRA Val de Loire, France
| | | | | | - Said Yous
- UMR-S 1172-LiNC-Lille Neuroscience & Cognition, Univ. Lille, INSERM, CHU Lille, France
| | - Jean A Boutin
- Institut de Recherches Internationales Servier, France
| | | | - Jérôme Leprince
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Normandie Université, UNIROUEN, INSERM 1239, France
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Tang L, Zhang C, Yang Q, Xie H, Liu D, Tian H, Lu L, Xu JY, Li W, Xu G, Qiu Q, Liu K, Luo D, Xu GT, Zhang J. Melatonin maintains inner blood-retinal barrier via inhibition of p38/TXNIP/NF-κB pathway in diabetic retinopathy. J Cell Physiol 2021; 236:5848-5864. [PMID: 33432588 DOI: 10.1002/jcp.30269] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 12/15/2020] [Accepted: 12/28/2020] [Indexed: 01/03/2023]
Abstract
The pathophysiology of diabetic retinopathy (DR) was complex. Under hyperglycemic conditions, the release of proinflammatory cytokines and the adhesion of leukocytes to retinal capillaries contribute to endothelial damage and the subsequent increase in vascular permeability resulting in macular edema. Melatonin, produced in the retina to regulate redox reactions and dopamine metabolism, plays protective roles against inflammation and oxidative stress. Considering its anti-inflammatory and antioxidative properties, melatonin was speculated to exert beneficial effects in DR. In this study, we characterized the protective effects of melatonin on the inner blood-retinal barrier (iBRB), as well as the possible mechanisms in experimental DR. Results showed that in diabetic rat retinas, the leakage of iBRB and the expression of inflammatory factors (VEGF, TNF-α, IL-1β, ICAM-1, and MMP9) increased dramatically, while the expression of tight junction proteins (ZO-1, occludin, JAM-A, and claudin-5) decreased significantly. The above changes were largely ameliorated by melatonin. The in vivo data were confirmed in vitro. In addition, the protein expressions of p38 MAPK, NF-κB, and TXNIP were upregulated significantly in diabetes and were downregulated following melatonin treatment. Melatonin could maintain the iBRB integrity by upregulating the expression of tight junction proteins via inhibiting p38/TXNIP/NF-κB pathway, thus decreasing the production of inflammatory factors. This study may shed light on the development of melatonin-based DR therapy.
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Affiliation(s)
- Lei Tang
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Chaoyang Zhang
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University, Shanghai, China
| | - Qian Yang
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Hai Xie
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Dandan Liu
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Haibin Tian
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Lixia Lu
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Jing-Ying Xu
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Weiye Li
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
- Department of Ophthalmology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States
| | - Guoxu Xu
- Department of Ophthalmology, the Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Qinghua Qiu
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Kun Liu
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Dawei Luo
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Guo-Tong Xu
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Jingfa Zhang
- Department of Regenerative Medicine, and Department of Pharmacology, Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
- Department of Ophthalmology, Shanghai General Hospital (Shanghai First People's Hospital), Shanghai Jiao Tong University, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai Key Laboratory of Ocular Fundus Diseases, Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
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18
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Boutin JA, Jockers R. Melatonin controversies, an update. J Pineal Res 2021; 70:e12702. [PMID: 33108677 DOI: 10.1111/jpi.12702] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/11/2020] [Accepted: 10/20/2020] [Indexed: 12/13/2022]
Abstract
Melatonin was discovered more than 60 years ago. Since then, several seminal discoveries have allowed us to define its function as a neuroendocrine hormone and its molecular targets in mammals and many other species. However, many fundamental issues have not yet been solved such as the subcellular localization of melatonin synthesis and the full spectrum of its molecular targets. In addition, a considerable number of controversies persist in the field, mainly concerning how many functions melatonin has. Altogether, this illustrates how "immature" the field still is. The intention of this opinion article is to note the controversies and limitations in the field, to initiate a discussion and to make proposals/guidelines to overcome them and move the field forward.
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Affiliation(s)
- Jean A Boutin
- Institut de Recherches Internationales SERVIER, Suresnes Cedex, France
| | - Ralf Jockers
- INSERM, CNRS, Institut Cochin, Université de Paris, Paris, France
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19
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Cecon E, Legros C, Boutin JA, Jockers R. Journal of pineal research guideline for authors: Defining and characterizing melatonin targets. J Pineal Res 2021; 70:e12712. [PMID: 33332653 DOI: 10.1111/jpi.12712] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/04/2020] [Accepted: 12/05/2020] [Indexed: 12/15/2022]
Abstract
A multitude of effects has been attributed to melatonin at pmol/L to mmol/L concentrations. More than fifteen targets have been proposed for melatonin but only few of them are well characterized. The current guidelines intend to provide a framework to improve and rationalize the characterization of melatonin targets and effects. They should be considered as mandatory guidelines and minimum requirements for manuscripts submitted to the Journal of Pineal Research.
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Affiliation(s)
- Erika Cecon
- Institut Cochin, CNRS, INSERM, Université de Paris, Paris, France
| | - Céline Legros
- Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Jean A Boutin
- Institut de Recherches SERVIER, Croissy-sur-Seine, France
| | - Ralf Jockers
- Institut Cochin, CNRS, INSERM, Université de Paris, Paris, France
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20
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Kopustinskiene DM, Bernatoniene J. Molecular Mechanisms of Melatonin-Mediated Cell Protection and Signaling in Health and Disease. Pharmaceutics 2021; 13:pharmaceutics13020129. [PMID: 33498316 PMCID: PMC7909293 DOI: 10.3390/pharmaceutics13020129] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/14/2021] [Accepted: 01/18/2021] [Indexed: 01/07/2023] Open
Abstract
Melatonin, an endogenously synthesized indolamine, is a powerful antioxidant exerting beneficial action in many pathological conditions. Melatonin protects from oxidative stress in ischemic/reperfusion injury, neurodegenerative diseases, and aging, decreases inflammation, modulates the immune system, inhibits proliferation, counteracts the Warburg effect, and promotes apoptosis in various cancer models. Melatonin stimulates antioxidant enzymes in the cells, protects mitochondrial membrane phospholipids, especially cardiolipin, from oxidation thus preserving integrity of the membranes, affects mitochondrial membrane potential, stimulates activity of respiratory chain enzymes, and decreases the opening of mitochondrial permeability transition pore and cytochrome c release. This review will focus on the molecular mechanisms of melatonin effects in the cells during normal and pathological conditions and possible melatonin clinical applications.
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Affiliation(s)
- Dalia M. Kopustinskiene
- Institute of Pharmaceutical Technologies, Faculty of Pharmacy, Medical Academy, Lithuanian University of Health Sciences, Sukileliu pr. 13, LT-50161 Kaunas, Lithuania;
| | - Jurga Bernatoniene
- Institute of Pharmaceutical Technologies, Faculty of Pharmacy, Medical Academy, Lithuanian University of Health Sciences, Sukileliu pr. 13, LT-50161 Kaunas, Lithuania;
- Department of Drug Technology and Social Pharmacy, Faculty of Pharmacy, Medical Academy, Lithuanian University of Health Sciences, Sukileliu pr. 13, LT-50161 Kaunas, Lithuania
- Correspondence:
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21
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Role of Melatonin on Virus-Induced Neuropathogenesis-A Concomitant Therapeutic Strategy to Understand SARS-CoV-2 Infection. Antioxidants (Basel) 2021; 10:antiox10010047. [PMID: 33401749 PMCID: PMC7823793 DOI: 10.3390/antiox10010047] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/23/2020] [Accepted: 12/29/2020] [Indexed: 12/12/2022] Open
Abstract
Viral infections may cause neurological disorders by directly inducing oxidative stress and interrupting immune system function, both of which contribute to neuronal death. Several reports have described the neurological manifestations in Covid-19 patients where, in severe cases of the infection, brain inflammation and encephalitis are common. Recently, extensive research-based studies have revealed and acknowledged the clinical and preventive roles of melatonin in some viral diseases. Melatonin has been shown to have antiviral properties against several viral infections which are accompanied by neurological symptoms. The beneficial properties of melatonin relate to its properties as a potent antioxidant, anti-inflammatory, and immunoregulatory molecule and its neuroprotective effects. In this review, what is known about the therapeutic role of melatonin in virus-induced neuropathogenesis is summarized and discussed.
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22
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Reiter RJ, Sharma R. Central and peripheral actions of melatonin on reproduction in seasonal and continuous breeding mammals. Gen Comp Endocrinol 2021; 300:113620. [PMID: 32950582 DOI: 10.1016/j.ygcen.2020.113620] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 09/13/2020] [Indexed: 02/08/2023]
Abstract
Under field conditions, especially for mammals that inhabit high latitudes, the regulation of seasonal breeding activity to ensure delivery of the young at the time most conducive to their survival is essential. This is most frequently accomplished by the annual reproductive cycle being linked to seasonal photoperiod changes which determine the nocturnal duration of the pineal melatonin signal. Mating can occur during any season that ensures spring/early summer delivery of the offspring. Thus, the season of mating is determined by the duration of pregnancy. The precise hormonal control of the annual cycle of reproduction by melatonin is accomplished at the level of the hypothalamo-pituitary axis which, in turn, determines the physiological state of the gonad and adnexa due to the regulation of pituitary gonadotrophin release. Many species are continuous rather than seasonal breeders. In these species, melatonin has a minor hormonal influence on the central regulation of reproduction but, nevertheless, its antioxidant functions at the level of the gonads support optimal reproductive physiology. Possibly like all cells, those in the ovary, e.g., granulosa cells and oocytes (less is known about melatonin synthesis by the testes or spermatogenic cells), synthesize melatonin which is used locally to combat free radicals and reactive nitrogen species which would otherwise cause oxidative/nitrosative stress to these critically important cells. Oxidative damage to the oocyte, zygote, blastocyst, etc., results in an abnormal fetus which is either sloughed or gives rise to an unhealthy offspring. The importance of the protection of the gametes (both oocytes and sperm) from oxidative molecular mutilation cannot be overstated. Fortunately, as a highly effective free radical scavenger and indirect antioxidant (by upregulating antioxidant enzyme), locally-produced melatonin is in the optimal location to protect the reproductive system from such damage.
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Affiliation(s)
- Russel J Reiter
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX, United States.
| | - Ramaswamy Sharma
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX, United States
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23
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New insights into antimetastatic signaling pathways of melatonin in skeletomuscular sarcoma of childhood and adolescence. Cancer Metastasis Rev 2020; 39:303-320. [PMID: 32086631 DOI: 10.1007/s10555-020-09845-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Melatonin is an indole produced by the pineal gland at night under normal light or dark conditions, and its levels, which are higher in children than in adults, begin to decrease prior to the onset of puberty and continue to decline thereafter. Apart from circadian regulatory actions, melatonin has significant apoptotic, angiogenic, oncostatic, and antiproliferative effects on various cancer cells. Particularly, the ability of melatonin to inhibit skeletomuscular sarcoma, which most commonly affects children, teenagers, and young adults, is substantial. In the past few decades, the vast majority of references have focused on the concept of epithelial-mesenchymal transition involvement in invasion and migration to allow carcinoma cells to dissociate from each other and to degrade the extracellular matrix. Recently, researchers have applied this idea to sarcoma cells of mesenchymal origin, e.g., osteosarcoma and Ewing sarcoma, with their ability to initiate the invasion-metastasis cascade. Similarly, interest of the effects of melatonin has shifted from carcinomas to sarcomas. Herein, in this state-of-the-art review, we compiled the knowledge related to the molecular mechanism of antimetastatic actions of melatonin on skeletomuscular sarcoma as in childhood and during adolescence. Utilization of melatonin as an adjuvant with chemotherapeutic drugs for synergy and fortification of the antimetastatic effects for the reinforcement of therapeutic actions are considered.
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Reiter RJ, Rosales-Corral S, Sharma R. Circadian disruption, melatonin rhythm perturbations and their contributions to chaotic physiology. Adv Med Sci 2020; 65:394-402. [PMID: 32763813 DOI: 10.1016/j.advms.2020.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 06/15/2020] [Accepted: 07/08/2020] [Indexed: 02/07/2023]
Abstract
The aim of this report is to summarize the data documenting the vital nature of well-regulated cellular and organismal circadian rhythms, which are also reflected in a stable melatonin cycle, in supporting optimal health. Cellular fluctuations in physiology exist in most cells of multicellular organisms with their stability relying on the prevailing light:dark cycle, since it regulates, via specialized intrinsically-photoreceptive retinal ganglion cells (ipRGC) and the retinohypothalamic tract, the master circadian oscillator, i.e., the suprachiasmatic nuclei (SCN). The output message of the SCN, as determined by the light:dark cycle, is transferred to peripheral oscillators, so-called slave cellular oscillators, directly via the autonomic nervous system with its limited distribution. and indirectly via the pineal-derived circulating melatonin rhythm, which contacts every cell. Via its regulatory effects on the neuroendocrine system, particularly the hypothalamo-pituitary-adrenal axis, the SCN also has a major influence on the adrenal glucocorticoid rhythm which impacts neurological diseases and psychological behaviors. Moreover, the SCN regulates the circadian production and secretion of melatonin. When the central circadian oscillator is disturbed, such as by light at night, it passes misinformation to all organs in the body. When this occurs the physiology of cells becomes altered and normal cellular functions are compromised. This physiological upheaval is a precursor to pathologies. The deterioration of the SCN/pineal network is often a normal consequence of aging and its related diseases, but in today's societies where manufactured light is becoming progressively more common worldwide, the associated pathologies may also be occurring at an earlier age.
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Affiliation(s)
- Russel J Reiter
- Department of Cell Systems and Anatomy, UT Health, San Antonio, TX, USA.
| | - Sergio Rosales-Corral
- Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Guadalajara, Mexico
| | - Ramaswamy Sharma
- Department of Cell Systems and Anatomy, UT Health, San Antonio, TX, USA
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Rzepka-Migut B, Paprocka J. Melatonin-Measurement Methods and the Factors Modifying the Results. A Systematic Review of the Literature. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E1916. [PMID: 32183489 PMCID: PMC7142625 DOI: 10.3390/ijerph17061916] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 03/04/2020] [Accepted: 03/06/2020] [Indexed: 01/11/2023]
Abstract
Melatonin plays an important role in regulating the sleep-wake cycle and adaptation to environmental changes. Concentration measurements in bioliquids such as serum/plasma, saliva and urine are widely used to assess peripheral rhythm. The aim of the study was to compare methods and conditions of determinations carried out with the identification of factors potentially affecting the measurements obtained. We have identified a group of modifiable and unmodifiable factors that facilitate data interpretation. Knowledge of modifiers allows you to carefully plan the test protocol and then compare the results. There is no one universal sampling standard, because the choice of method and biofluid depends on the purpose of the study and the research group.
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Affiliation(s)
- Beata Rzepka-Migut
- Department of Pediatric Neurology and Pediatrics, St. Queen Jadwiga’s Regional Clinical Hospital No 2 Rzeszów, 35-301 Rzeszów, Poland;
| | - Justyna Paprocka
- Department of Pediatric Neurology, Faculty of Medical Sciences, Medical University of Silesia, 40-752 Katowice, Poland
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26
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Gorman MR. Temporal organization of pineal melatonin signaling in mammals. Mol Cell Endocrinol 2020; 503:110687. [PMID: 31866317 DOI: 10.1016/j.mce.2019.110687] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 12/13/2019] [Accepted: 12/14/2019] [Indexed: 12/20/2022]
Abstract
In mammals, the pineal gland is the sole endocrine source of melatonin, which is secreted according to daily and seasonal patterns. This mini-review synthesizes the established endocrine actions of melatonin in the following temporal contexts. Melatonin is a strictly regulated output of the circadian timing system, but under certain conditions, may also entrain the circadian pacemaker and clocks in peripheral tissues. As the waveform of nightly melatonin secretion varies seasonally, melatonin provides a hormonal representation of the time of year. The duration of elevated melatonin secretion regulates reproductive physiology and other seasonal adaptations either by entraining a circannual rhythm or by inducing seasonal responses directly. An entrainment action of nightly melatonin on clock gene expression in the pars tuberalis of the anterior pituitary may partly underly its mechanistic role as a photoperiodic switch. Melatonin has important functions developmentally to regulate multiple physiological systems and program timing of puberty. Endogenous melatonergic systems are disrupted by modern lifestyles of humans through altered circadian entrainment, acute suppression by light and self-administration of pharmacological melatonin. Non-endocrine actions of locally synthesized melatonin fall outside of the scope of this mini-review.
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Affiliation(s)
- Michael R Gorman
- Departments of Psychology and Center for Circadian Biology, University of California, San Diego, La Jolla, CA, 92093-0109, USA.
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27
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Patel S, Rahmani B, Gandhi J, Seyam O, Joshi G, Reid I, Smith NL, Waltzer WC, Khan SA. Revisiting the pineal gland: a review of calcification, masses, precocious puberty, and melatonin functions. Int J Neurosci 2020; 130:464-475. [PMID: 31714865 DOI: 10.1080/00207454.2019.1692838] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Introduction: The pineal gland, an endocrine organ of the posterior cranial fossa famously involved in sleep and wakefulness, has continually been a topic of scientific advancement and curiosity. Methods: We review present an up-to-date review including the anatomy, embryology, and physiology of the pineal gland and its ability to secrete hormones including melatonin, pathophysiology of pineal gland tumors, cysts, and calcifications, their clinical presentation including their association with parkinsonism and precocious puberty, and various treatment approaches. Results: Exploring the biochemistry of melatonin, various calcification morphologies, and pineal tumors may uncover a wider role and the exhaustive case study consolidation allows clinicians to carefully review the literature and aid their treatment approaches. Conclusion: It is imperative that clinicians and diagnosticians are able to distinguish manifestations of an overlooked gland.
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Affiliation(s)
- Shrey Patel
- Department of Physiology and Biophysics, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
| | - Benjamin Rahmani
- Department of Physiology and Biophysics, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
| | - Jason Gandhi
- Department of Physiology and Biophysics, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA.,Medical Student Research Institute, St. George's University School of Medicine, Grenada, West Indies
| | - Omar Seyam
- Department of Physiology and Biophysics, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
| | - Gunjan Joshi
- Department of Internal Medicine, Stony Brook Southampton Hospital, Southampton, NY, USA
| | - Inefta Reid
- Department of Physiology and Biophysics, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
| | | | - Wayne C Waltzer
- Department of Urology, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
| | - Sardar Ali Khan
- Department of Physiology and Biophysics, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA.,Department of Urology, Stony Brook University Renaissance School of Medicine, Stony Brook, NY, USA
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28
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Legros C, Dupré C, Brasseur C, Bonnaud A, Bruno O, Valour D, Shabajee P, Giganti A, Nosjean O, Kenakin TP, Boutin JA. Characterization of the various functional pathways elicited by synthetic agonists or antagonists at the melatonin MT 1 and MT 2 receptors. Pharmacol Res Perspect 2020; 8:e00539. [PMID: 31893123 PMCID: PMC6935685 DOI: 10.1002/prp2.539] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 09/30/2019] [Accepted: 10/10/2019] [Indexed: 12/20/2022] Open
Abstract
Melatonin is a neurohormone that translates the circadian rhythm to the peripheral organs through a series of binding sites identified as G protein-coupled receptors MT1 and MT2. Due to minute amounts of receptor proteins in target organs, the main tool of studies of the melatoninergic system is recombinant expression of the receptors in cellular hosts. Although a number of studies exist on these receptors, studies of several signaling pathways using a large number of melatoninergic compounds are rather limited. We chose to fill this gap to better describe a panel of compounds that have been only partially characterized in terms of functionality. First, we characterized HEK cells expressing MT1 or MT2, and several signaling routes with melatonin itself to validate the approach: GTPγS, cAMP production, internalization, β-arrestin recruitment, and cell morphology changes (CellKey ® ). Second, we chose 21 compounds from our large melatoninergic chemical library and characterized them using this panel of signaling pathways. Notably, antagonists were infrequent, and their functionality depended largely on the pathway studied. This will permit redefining the availability of molecular tools that can be used to better understand the in situ activity and roles of these receptors.
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Affiliation(s)
- Céline Legros
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Clémence Dupré
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Chantal Brasseur
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Anne Bonnaud
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Olivier Bruno
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Damien Valour
- Pôle d’Expetise Méthodologie et Valorisation des DonnéesInstitut de Recherches Internationales ServierSuresnesFrance
| | - Preety Shabajee
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Adeline Giganti
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
| | - Olivier Nosjean
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
- Present address:
Institut de Recherches Internationales SERVIERSuresnesFrance
| | - Terrence P. Kenakin
- Department of PharmacologyUniversity of North Carolina School of MedicineChapel HillNCUSA
| | - Jean A. Boutin
- Pôle d’Expertise BiotechnologieChimie & BiologieInstitut de Recherches ServierCroissy‐sur‐SeineFrance
- Present address:
Institut de Recherches Internationales SERVIERSuresnesFrance
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Kirsz K, Szczęsna M, Biernat W, Molik E, Zięba DA. Involvement of orexin A in nocturnal melatonin secretion into the cerebrospinal fluid and the blood plasma in seasonal sheep. Gen Comp Endocrinol 2020; 286:113304. [PMID: 31654677 DOI: 10.1016/j.ygcen.2019.113304] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/18/2019] [Accepted: 10/20/2019] [Indexed: 01/28/2023]
Abstract
In sheep, differences in orexin A (OXA) gene expression and activity are related to changes in energy demand and seasonal reproduction. However, the mechanism by which and the key place where the OXA signal is integrated with photoperiod, whose main biochemical expression is melatonin (MEL), remain unknown. We examined the effects of cisterna magna injections of OXA (0.3 μg/kg body weight) on nocturnal cerebrospinal fluid (CSF) and plasma MEL concentrations; mRNA and protein expression of two rate-limiting enzymes for MEL biosynthesis, tryptophan 5-hydroxylase-1 (TPH1) and arylalkylamine-N-acetyltransferase (AA-NAT); and OXA receptor (OX1R, OX2R) expression in the pineal gland (PG) obtained from twenty ewes during the short-day (SD) and long-day (LD) seasons. OXA increased (P < 0.001) CSF and plasma MEL concentrations regardless of the season. Plasma MEL was positively correlated (P < 0.001) with CSF MEL in the OXA-treated sheep in both seasons. OXA had no effect (P > 0.05) on TPH1 transcript or protein level but upregulated (P < 0.05) AA-NAT mRNA and protein expression in both seasons. OXA enhanced (P < 0.05) OX1R mRNA level only during the LD season. Our results show that the endocrine activity of the ovine PG is regulated by day length and non-photic signals via hypothalamic OXA. These results are important for understanding the work of the biological clock and recognizing mechanisms responsible for the adaptation of seasonal animals to the changing external environment conditions. OXA and MEL are both involved in the regulation of the sleep-wakefulness system, therefore our results can be used in the study on the circadian rhythm disorders in humans (e.g. jet lag, insomnia, seasonal depression).
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Affiliation(s)
- Katarzyna Kirsz
- University of Agriculture in Krakow, Department of Animal Biotechnology, 1B Rędzina Street, 31-248 Krakow, Poland.
| | - Małgorzata Szczęsna
- University of Agriculture in Krakow, Department of Animal Biotechnology, 1B Rędzina Street, 31-248 Krakow, Poland.
| | - Weronika Biernat
- University of Agriculture in Krakow, Department of Animal Biotechnology, 1B Rędzina Street, 31-248 Krakow, Poland
| | - Edyta Molik
- University of Agriculture in Krakow, Department of Animal Biotechnology, 1B Rędzina Street, 31-248 Krakow, Poland.
| | - Dorota A Zięba
- University of Agriculture in Krakow, Department of Animal Biotechnology, 1B Rędzina Street, 31-248 Krakow, Poland.
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Bothwell SW, Janigro D, Patabendige A. Cerebrospinal fluid dynamics and intracranial pressure elevation in neurological diseases. Fluids Barriers CNS 2019; 16:9. [PMID: 30967147 PMCID: PMC6456952 DOI: 10.1186/s12987-019-0129-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 03/19/2019] [Indexed: 01/09/2023] Open
Abstract
The fine balance between the secretion, composition, volume and turnover of cerebrospinal fluid (CSF) is strictly regulated. However, during certain neurological diseases, this balance can be disrupted. A significant disruption to the normal CSF circulation can be life threatening, leading to increased intracranial pressure (ICP), and is implicated in hydrocephalus, idiopathic intracranial hypertension, brain trauma, brain tumours and stroke. Yet, the exact cellular, molecular and physiological mechanisms that contribute to altered hydrodynamic pathways in these diseases are poorly defined or hotly debated. The traditional views and concepts of CSF secretion, flow and drainage have been challenged, also due to recent findings suggesting more complex mechanisms of brain fluid dynamics than previously proposed. This review evaluates and summarises current hypotheses of CSF dynamics and presents evidence for the role of impaired CSF dynamics in elevated ICP, alongside discussion of the proteins that are potentially involved in altered CSF physiology during neurological disease. Undoubtedly CSF secretion, absorption and drainage are important aspects of brain fluid homeostasis in maintaining a stable ICP. Traditionally, pharmacological interventions or CSF drainage have been used to reduce ICP elevation due to over production of CSF. However, these drugs are used only as a temporary solution due to their undesirable side effects. Emerging evidence suggests that pharmacological targeting of aquaporins, transient receptor potential vanilloid type 4 (TRPV4), and the Na+-K+-2Cl- cotransporter (NKCC1) merit further investigation as potential targets in neurological diseases involving impaired brain fluid dynamics and elevated ICP.
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Affiliation(s)
- Steven William Bothwell
- Brain Barriers Group, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Medical Sciences Building, University Drive, Callaghan, NSW 2308 Australia
| | - Damir Janigro
- FloTBI Inc., Cleveland, OH USA
- Department of Physiology, Case Western Reserve University, Cleveland, OH USA
| | - Adjanie Patabendige
- Brain Barriers Group, School of Biomedical Sciences and Pharmacy, The University of Newcastle, Medical Sciences Building, University Drive, Callaghan, NSW 2308 Australia
- Hunter Medical Research Institute, Newcastle, NSW Australia
- The Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
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Abstract
Despite considerable advances in the past few years, obesity and type 2 diabetes mellitus (T2DM) remain two major challenges for public health systems globally. In the past 9 years, genome-wide association studies (GWAS) have established a major role for genetic variation within the MTNR1B locus in regulating fasting plasma levels of glucose and in affecting the risk of T2DM. This discovery generated a major interest in the melatonergic system, in particular the melatonin MT2 receptor (which is encoded by MTNR1B). In this Review, we discuss the effect of melatonin and its receptors on glucose homeostasis, obesity and T2DM. Preclinical and clinical post-GWAS evidence of frequent and rare variants of the MTNR1B locus confirmed its importance in regulating glucose homeostasis and T2DM risk with minor effects on obesity. However, these studies did not solve the question of whether melatonin is beneficial or detrimental, an issue that will be discussed in the context of the peculiarities of the melatonergic system. Melatonin receptors might have therapeutic potential as they belong to the highly druggable G protein-coupled receptor superfamily. Clarifying the precise role of melatonin and its receptors on glucose homeostasis is urgent, as melatonin is widely used for other indications, either as a prescribed medication or as a supplement without medical prescription, in many countries in Europe and in the USA.
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Affiliation(s)
- Angeliki Karamitri
- Inserm, U1016, Institut Cochin, Paris, France
- CNRS UMR 8104, Paris, France
- Université Paris Descartes, Université Sorbonne Paris Cité, Paris, France
| | - Ralf Jockers
- Inserm, U1016, Institut Cochin, Paris, France.
- CNRS UMR 8104, Paris, France.
- Université Paris Descartes, Université Sorbonne Paris Cité, Paris, France.
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32
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Liu L, Labani N, Cecon E, Jockers R. Melatonin Target Proteins: Too Many or Not Enough? Front Endocrinol (Lausanne) 2019; 10:791. [PMID: 31803142 PMCID: PMC6872631 DOI: 10.3389/fendo.2019.00791] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 10/30/2019] [Indexed: 12/17/2022] Open
Abstract
The neurohormone N-acetyl-5-methoxytryptamine, better known as melatonin, is a tryptophan derivative with a wide range of biological effects that is present in many organisms. These effects are believed to rely either on the chemical properties of melatonin itself as scavenger of free radicals or on the binding of melatonin to protein targets. More than 15 proteins, including receptors (MT1, MT2, Mel1c, CAND2, ROR, VDR), enzymes (QR2, MMP-9, pepsin, PP2A, PR-10 proteins), pores (mtPTP), transporters (PEPT1/2, Glut1), and other proteins (HBS, CaM, tubulin, calreticuline), have been suggested to interact with melatonin at sub-nanomolar to millimolar melatonin concentrations. In this review we assemble for the first time the available information on proposed melatonin targets and discuss them in a comprehensive manner to evaluate the robustness of these findings in terms of methodology, physiological relevance, and independent replication.
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Affiliation(s)
- Lei Liu
- Cellular Signaling Laboratory, International Research Center for Sensory Biology and Technology of MOST, Key Laboratory of Molecular Biophysics of Ministry of Education, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Nedjma Labani
- Cellular Signaling Laboratory, International Research Center for Sensory Biology and Technology of MOST, Key Laboratory of Molecular Biophysics of Ministry of Education, School of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Erika Cecon
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Ralf Jockers
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
- *Correspondence: Ralf Jockers
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Farfán-García ED, Márquez-Gómez R, Barrón-González M, Pérez-Capistran T, Rosales-Hernández MC, Pinto-Almazán R, Soriano-Ursúa MA. Monoamines and their Derivatives on GPCRs: Potential Therapy for Alzheimer's Disease. Curr Alzheimer Res 2019; 16:871-894. [PMID: 30963972 DOI: 10.2174/1570159x17666190409144558] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/18/2019] [Accepted: 04/01/2019] [Indexed: 02/07/2023]
Abstract
Albeit cholinergic depletion remains the key event in Alzheimer's Disease (AD), recent information describes stronger links between monoamines (trace amines, catecholamines, histamine, serotonin, and melatonin) and AD than those known in the past century. Therefore, new drug design strategies focus efforts to translate the scope on these topics and to offer new drugs which can be applied as therapeutic tools in AD. In the present work, we reviewed the state-of-art regarding genetic, neuropathology and neurochemistry of AD involving monoamine systems. Then, we compiled the effects of monoamines found in the brain of mammals as well as the reported effects of their derivatives and some structure-activity relationships. Recent derivatives have triggered exciting effects and pharmacokinetic properties in both murine models and humans. In some cases, the mechanism of action is clear, essentially through the interaction on G-protein-coupled receptors as revised in this manuscript. Additional mechanisms are inhibition of enzymes for their biotransformation, regulation of free-radicals in the central nervous system and others for the effects on Tau phosphorylation or amyloid-beta accumulation. All these data make the monoamines and their derivatives attractive potential elements for AD therapy.
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Affiliation(s)
- Eunice D Farfán-García
- Departamento de Fisiologia y Bioquimica. Seccion de Estudios de Posgrado e Investigacion, Escuela Superior de Medicina, Instituto Politecnico Nacional, Plan de San Luis y Diaz Miron s/n, 11340, Mexico City, Mexico
| | - Ricardo Márquez-Gómez
- MRC Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, OX1 3TH, Oxford, United Kingdom
| | - Mónica Barrón-González
- Departamento de Fisiologia y Bioquimica. Seccion de Estudios de Posgrado e Investigacion, Escuela Superior de Medicina, Instituto Politecnico Nacional, Plan de San Luis y Diaz Miron s/n, 11340, Mexico City, Mexico
| | - Teresa Pérez-Capistran
- Departamento de Fisiologia y Bioquimica. Seccion de Estudios de Posgrado e Investigacion, Escuela Superior de Medicina, Instituto Politecnico Nacional, Plan de San Luis y Diaz Miron s/n, 11340, Mexico City, Mexico
| | - Martha C Rosales-Hernández
- Laboratorio de Biofisica y Biocatalisis, Seccion de Estudios de Posgrado e Investigacion Escuela Superior de Medicina, Instituto Politecnico Nacional, Plan de San Luis y Diaz Miron s/n, 11340, Mexico City, Mexico
| | - Rodolfo Pinto-Almazán
- Unidad de Investigacion Hospital Regional de Alta Especialidad Ixtapaluca, Carretera Federal Mexico-Puebla km 34.5, C.P. 56530. Ixtapaluca, State of Mexico, Mexico
| | - Marvin A Soriano-Ursúa
- Departamento de Fisiologia y Bioquimica. Seccion de Estudios de Posgrado e Investigacion, Escuela Superior de Medicina, Instituto Politecnico Nacional, Plan de San Luis y Diaz Miron s/n, 11340, Mexico City, Mexico
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Reiter RJ, Tan DX, Rosales-Corral S, Galano A, Jou MJ, Acuna-Castroviejo D. Melatonin Mitigates Mitochondrial Meltdown: Interactions with SIRT3. Int J Mol Sci 2018; 19:E2439. [PMID: 30126181 PMCID: PMC6121285 DOI: 10.3390/ijms19082439] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/03/2018] [Accepted: 08/08/2018] [Indexed: 02/07/2023] Open
Abstract
Melatonin exhibits extraordinary diversity in terms of its functions and distribution. When discovered, it was thought to be uniquely of pineal gland origin. Subsequently, melatonin synthesis was identified in a variety of organs and recently it was shown to be produced in the mitochondria. Since mitochondria exist in every cell, with a few exceptions, it means that every vertebrate, invertebrate, and plant cell produces melatonin. The mitochondrial synthesis of melatonin is not photoperiod-dependent, but it may be inducible under conditions of stress. Mitochondria-produced melatonin is not released into the systemic circulation, but rather is used primarily in its cell of origin. Melatonin's functions in the mitochondria are highly diverse, not unlike those of sirtuin 3 (SIRT3). SIRT3 is an NAD+-dependent deacetylase which regulates, among many functions, the redox state of the mitochondria. Recent data proves that melatonin and SIRT3 post-translationally collaborate in regulating free radical generation and removal from mitochondria. Since melatonin and SIRT3 have cohabitated in the mitochondria for many eons, we predict that these molecules interact in many other ways to control mitochondrial physiology. It is predicted that these mutual functions will be intensely investigated in the next decade and importantly, we assume that the findings will have significant applications for preventing/delaying some age-related diseases and aging itself.
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Affiliation(s)
- Russel J Reiter
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
| | - Dun Xian Tan
- Department of Cell Systems and Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
| | - Sergio Rosales-Corral
- Centro de Investigacion Biomedica de Occidente, Instituto Mexicano del Seguro Social, Guardalajara, 4436 Jalisco, Mexico.
| | - Annia Galano
- Departamento de Quimica, Universidad Antonoma Metropolitana-Unidad Iztapalapa, San Rafael Atlixco 186, Col. Vicentina, Iztapalapa, C.P. 09340 Mexico D.F., Mexico.
| | - Mei-Jie Jou
- Department of Physiology and Pharmacology, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan, Tao-Yuan 333, Taiwan.
| | - Dario Acuna-Castroviejo
- Departamento de Fisiologia, Instituto de Biotecnologia, Universidad de Granada, Avenida de Conocimiento S/U, 18016 Granada, Spain.
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The Timing of Melatonin Administration Is Crucial for Its Antidepressant-Like Effect in Mice. Int J Mol Sci 2018; 19:ijms19082278. [PMID: 30081472 PMCID: PMC6121277 DOI: 10.3390/ijms19082278] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/17/2018] [Accepted: 07/20/2018] [Indexed: 12/13/2022] Open
Abstract
Melatonin is synthesized by the pineal gland with a circadian rhythm in synchrony with the environmental light/dark cycle. A gradual increase in circulating levels of melatonin occur after lights off, reaching its maximum around the middle of the dark phase. Agonists of melatonin receptors have proved effectiveness as antidepressants in clinical trials. However, there is contradictory evidence about the potential antidepressant effect of melatonin itself. Herein we studied melatonin administration in mice at two zeitgeber times (ZT; ZT = 0 lights on; 12:12 L/D), one hour before the beginning (ZT11) and at the middle (ZT18) of the dark phase after either a single or a three-dose protocol. Behavioral despair was assessed through a forced-swimming test (FST) or a tail suspension test (TST), at ZT18.5. A single dose of 4 mg/kg melatonin at ZT11 was effective to reduce the immobility time in both tests. However, acute administration of melatonin at ZT18 was not effective in mice subjected to FST, and a higher dose (16 mg/kg) was required to reduce immobility time in the TST. A three-dose administration protocol of 16 mg/kg melatonin (ZT18, ZT11, and ZT18) significantly reduced immobility time in FST. Data indicate that the timely administration of melatonin could improve its antidepressant-like effect.
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Abbott NJ, Pizzo ME, Preston JE, Janigro D, Thorne RG. The role of brain barriers in fluid movement in the CNS: is there a 'glymphatic' system? Acta Neuropathol 2018; 135:387-407. [PMID: 29428972 DOI: 10.1007/s00401-018-1812-4] [Citation(s) in RCA: 335] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/16/2018] [Accepted: 01/24/2018] [Indexed: 12/15/2022]
Abstract
Brain fluids are rigidly regulated to provide stable environments for neuronal function, e.g., low K+, Ca2+, and protein to optimise signalling and minimise neurotoxicity. At the same time, neuronal and astroglial waste must be promptly removed. The interstitial fluid (ISF) of the brain tissue and the cerebrospinal fluid (CSF) bathing the CNS are integral to this homeostasis and the idea of a glia-lymph or 'glymphatic' system for waste clearance from brain has developed over the last 5 years. This links bulk (convective) flow of CSF into brain along the outside of penetrating arteries, glia-mediated convective transport of fluid and solutes through the brain extracellular space (ECS) involving the aquaporin-4 (AQP4) water channel, and finally delivery of fluid to venules for clearance along peri-venous spaces. However, recent evidence favours important amendments to the 'glymphatic' hypothesis, particularly concerning the role of glia and transfer of solutes within the ECS. This review discusses studies which question the role of AQP4 in ISF flow and the lack of evidence for its ability to transport solutes; summarizes attributes of brain ECS that strongly favour the diffusion of small and large molecules without ISF flow; discusses work on hydraulic conductivity and the nature of the extracellular matrix which may impede fluid movement; and reconsiders the roles of the perivascular space (PVS) in CSF-ISF exchange and drainage. We also consider the extent to which CSF-ISF exchange is possible and desirable, the impact of neuropathology on fluid drainage, and why using CSF as a proxy measure of brain components or drug delivery is problematic. We propose that new work and key historical studies both support the concept of a perivascular fluid system, whereby CSF enters the brain via PVS convective flow or dispersion along larger caliber arteries/arterioles, diffusion predominantly regulates CSF/ISF exchange at the level of the neurovascular unit associated with CNS microvessels, and, finally, a mixture of CSF/ISF/waste products is normally cleared along the PVS of venules/veins as well as other pathways; such a system may or may not constitute a true 'circulation', but, at the least, suggests a comprehensive re-evaluation of the previously proposed 'glymphatic' concepts in favour of a new system better taking into account basic cerebrovascular physiology and fluid transport considerations.
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Affiliation(s)
- N Joan Abbott
- Faculty of Life Sciences and Medicine, Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building 3.82, 150 Stamford St, London, SE1 9NH, UK.
| | - Michelle E Pizzo
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison School of Pharmacy, Madison, WI, USA
- Clinical Neuroengineering Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Jane E Preston
- Faculty of Life Sciences and Medicine, Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building 3.82, 150 Stamford St, London, SE1 9NH, UK
| | - Damir Janigro
- Flocel Inc., Cleveland, OH, USA
- Department of Physiology, Case Western Reserve University, Cleveland, OH, USA
| | - Robert G Thorne
- Division of Pharmaceutical Sciences, University of Wisconsin-Madison School of Pharmacy, Madison, WI, USA.
- Clinical Neuroengineering Training Program, University of Wisconsin-Madison, Madison, WI, USA.
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA.
- Cellular and Molecular Pathology Graduate Training Program, University of Wisconsin-Madison, Madison, WI, USA.
- Institute for Clinical and Translational Research, University of Wisconsin-Madison, Madison, WI, USA.
- , 5113 Rennebohm Hall, 777 Highland Avenue, Madison, WI, 53705, USA.
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Tan DX, Xu B, Zhou X, Reiter RJ. Pineal Calcification, Melatonin Production, Aging, Associated Health Consequences and Rejuvenation of the Pineal Gland. Molecules 2018; 23:E301. [PMID: 29385085 PMCID: PMC6017004 DOI: 10.3390/molecules23020301] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 01/24/2018] [Accepted: 01/26/2018] [Indexed: 01/26/2023] Open
Abstract
The pineal gland is a unique organ that synthesizes melatonin as the signaling molecule of natural photoperiodic environment and as a potent neuronal protective antioxidant. An intact and functional pineal gland is necessary for preserving optimal human health. Unfortunately, this gland has the highest calcification rate among all organs and tissues of the human body. Pineal calcification jeopardizes melatonin's synthetic capacity and is associated with a variety of neuronal diseases. In the current review, we summarized the potential mechanisms of how this process may occur under pathological conditions or during aging. We hypothesized that pineal calcification is an active process and resembles in some respects of bone formation. The mesenchymal stem cells and melatonin participate in this process. Finally, we suggest that preservation of pineal health can be achieved by retarding its premature calcification or even rejuvenating the calcified gland.
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Affiliation(s)
- Dun Xian Tan
- Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
| | - Bing Xu
- Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
| | - Xinjia Zhou
- Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
| | - Russel J Reiter
- Department of Cell Systems & Anatomy, UT Health San Antonio, San Antonio, TX 78229, USA.
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Dehdashtian E, Mehrzadi S, Yousefi B, Hosseinzadeh A, Reiter RJ, Safa M, Ghaznavi H, Naseripour M. Diabetic retinopathy pathogenesis and the ameliorating effects of melatonin; involvement of autophagy, inflammation and oxidative stress. Life Sci 2018; 193:20-33. [DOI: 10.1016/j.lfs.2017.12.001] [Citation(s) in RCA: 163] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 11/19/2017] [Accepted: 12/01/2017] [Indexed: 12/12/2022]
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Markus RP, Fernandes PA, Kinker GS, da Silveira Cruz-Machado S, Marçola M. Immune-pineal axis - acute inflammatory responses coordinate melatonin synthesis by pinealocytes and phagocytes. Br J Pharmacol 2017; 175:3239-3250. [PMID: 29105727 DOI: 10.1111/bph.14083] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 08/21/2017] [Accepted: 09/20/2017] [Indexed: 12/12/2022] Open
Abstract
Melatonin is well known for its circadian production by the pineal gland, and there is a growing body of data showing that it is also produced by many other cells and organs, including immune cells. The chronobiotic role of pineal melatonin, as well as its protective effects in vitro and in vivo, have been extensively explored. However, the interaction between the chronobiotic and defence functions of endogenous melatonin has been little investigated. This review details the current knowledge regarding the coordinated shift in melatonin synthesis from the pineal gland (circadian and monitoring roles) to the regulation of acute immune responses via immune cell production and autocrine effects, producing systemic interactions termed the immune-pineal axis. An acute inflammatory response drives the transcription factor, NFκB, to switch melatonin synthesis from pinealocytes to macrophages/microglia and, upon acute inflammatory resolution, back to pinealocytes. The potential pathophysiological relevance of immune-pineal axis dysregulation is highlighted, with both research and clinical implications, across several medical conditions, including host/parasite interaction, neurodegenerative diseases and cancer. LINKED ARTICLES: This article is part of a themed section on Recent Developments in Research of Melatonin and its Potential Therapeutic Applications. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.16/issuetoc.
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Affiliation(s)
- Regina P Markus
- Laboratory of Chronopharmacology and Laboratory of Neuroimmunomodulation - Department of Physiology, Institute of Bioscience, University of São Paulo, São Paulo, Brazil
| | - Pedro A Fernandes
- Laboratory of Chronopharmacology and Laboratory of Neuroimmunomodulation - Department of Physiology, Institute of Bioscience, University of São Paulo, São Paulo, Brazil
| | - Gabriela S Kinker
- Laboratory of Chronopharmacology and Laboratory of Neuroimmunomodulation - Department of Physiology, Institute of Bioscience, University of São Paulo, São Paulo, Brazil
| | - Sanseray da Silveira Cruz-Machado
- Laboratory of Chronopharmacology and Laboratory of Neuroimmunomodulation - Department of Physiology, Institute of Bioscience, University of São Paulo, São Paulo, Brazil
| | - Marina Marçola
- Laboratory of Chronopharmacology and Laboratory of Neuroimmunomodulation - Department of Physiology, Institute of Bioscience, University of São Paulo, São Paulo, Brazil
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Dupré C, Bruno O, Bonnaud A, Giganti A, Nosjean O, Legros C, Boutin JA. Assessments of cellular melatonin receptor signaling pathways: β-arrestin recruitment, receptor internalization, and impedance variations. Eur J Pharmacol 2017; 818:534-544. [PMID: 29154938 DOI: 10.1016/j.ejphar.2017.11.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/03/2017] [Accepted: 11/13/2017] [Indexed: 12/30/2022]
Abstract
Melatonin receptors belong to the family of G-protein coupled receptors. Agonist-induced receptor activation is terminated with the recruitment of β-arrestin, which leads to receptor internalization. Furthermore, agonist binding induces a shift in cellular shape that translates into a change in the electric impedance of the cell. In the present study, we employed engineered cells to study these internalization-related processes in the context of the two melatonin receptors, MT1 and MT2. To assess these three receptor internalization-related functions and validate the results, we employed four classical ligands of melatonin receptors: the natural agonist melatonin; the super-agonist 2-iodo-melatonin and the two antagonists luzindole and 4-phenyl-2-propionamidotetralin. The assessments confirmed the nature of the agonistic ligands but showed that 4-phenyl-2-propionamidotetralin, a described antagonist, is a biased partial agonist at MT2 with poorer affinity for MT1. The methods are now available to be applied to any receptor system for which multiple signaling pathways must be evaluated for new molecules.
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Affiliation(s)
- Clémence Dupré
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France
| | - Olivier Bruno
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France
| | - Anne Bonnaud
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France
| | - Adeline Giganti
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France
| | - Olivier Nosjean
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France
| | - Céline Legros
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France
| | - Jean A Boutin
- Pôle d'Expertise Biotechnologie, Chimie, Biologie, Institut de Recherches SERVIER, 125, Chemin De Ronde, 78290 Croissy-sur-Seine, France.
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Yeh CM, Su SC, Lin CW, Yang WE, Chien MH, Reiter RJ, Yang SF. Melatonin as a potential inhibitory agent in head and neck cancer. Oncotarget 2017; 8:90545-90556. [PMID: 29163852 PMCID: PMC5685773 DOI: 10.18632/oncotarget.20079] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 07/26/2017] [Indexed: 12/29/2022] Open
Abstract
Melatonin is a molecule secreted by the pineal gland; it is an important regulator of sleep and circadian rhythms. Through multiple interrelated mechanisms, melatonin exhibits various inhibitory properties at different stages of tumor progression. Many studies have explored the oncostatic effects of melatonin on hormone-dependent tumors. In this review, we highlight recent advances in understanding the effects of melatonin on the development of head and neck cancers, including molecular mechanisms identified through experimental and clinical observations. Because melatonin exerts a wide range of effects, melatonin may influence many mechanisms that influence the development of cancer. These include cell proliferation, apoptosis, angiogenesis, extracellular matrix remodeling through matrix metalloproteinases, and genetic polymorphism. Thus, the evidence discussed in this article will serve as a basis for basic and clinical research to promote the use of melatonin for understanding and controlling the development of head and neck cancers.
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Affiliation(s)
- Chia-Ming Yeh
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Shih-Chi Su
- Whole-Genome Research Core Laboratory of Human Diseases, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Chiao-Wen Lin
- Institute of Oral Sciences, Chung Shan Medical University, Taichung, Taiwan.,Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Wei-En Yang
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.,Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Ming-Hsien Chien
- Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan
| | - Russel J Reiter
- Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, TX, USA
| | - Shun-Fa Yang
- Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.,Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan
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Kowalewska M, Szczepkowska A, Herman A, Pellicer-Rubio M, Jałyński M, Skipor J. Melatonin from slow-release implants did not influence the gene expression of the lipopolysaccharide receptor complex in the choroid plexus of seasonally anoestrous adult ewes subjected or not to a systemic inflammatory stimulus. Small Rumin Res 2017. [DOI: 10.1016/j.smallrumres.2016.11.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Shukla M, Govitrapong P, Boontem P, Reiter RJ, Satayavivad J. Mechanisms of Melatonin in Alleviating Alzheimer's Disease. Curr Neuropharmacol 2017; 15:1010-1031. [PMID: 28294066 PMCID: PMC5652010 DOI: 10.2174/1570159x15666170313123454] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 02/10/2017] [Accepted: 03/09/2017] [Indexed: 02/07/2023] Open
Abstract
Alzheimer's disease (AD) is a chronic, progressive and prevalent neurodegenerative disease characterized by the loss of higher cognitive functions and an associated loss of memory. The thus far "incurable" stigma for AD prevails because of variations in the success rates of different treatment protocols in animal and human studies. Among the classical hypotheses explaining AD pathogenesis, the amyloid hypothesis is currently being targeted for drug development. The underlying concept is to prevent the formation of these neurotoxic peptides which play a central role in AD pathology and trigger a multispectral cascade of neurodegenerative processes post-aggregation. This could possibly be achieved by pharmacological inhibition of β- or γ-secretase or stimulating the nonamyloidogenic α-secretase. Melatonin the pineal hormone is a multifunctioning indoleamine. Production of this amphiphilic molecule diminishes with advancing age and this decrease runs parallel with the progression of AD which itself explains the potential benefits of melatonin in line of development and devastating consequences of the disease progression. Our recent studies have revealed a novel mechanism by which melatonin stimulates the nonamyloidogenic processing and inhibits the amyloidogenic processing of β-amyloid precursor protein (βAPP) by stimulating α -secretases and consequently down regulating both β- and γ-secretases at the transcriptional level. In this review, we discuss and evaluate the neuroprotective functions of melatonin in AD pathogenesis, including its role in the classical hypotheses in cellular and animal models and clinical interventions in AD patients, and suggest that with early detection, melatonin treatment is qualified to be an anti-AD therapy.
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Affiliation(s)
- Mayuri Shukla
- Chulabhorn Graduate Institute, Chulabhorn Royal Academy, 54 Kamphaeng Phet 6 Road, Lak Si, Bangkok10210, Thailand
| | - Piyarat Govitrapong
- Chulabhorn Graduate Institute, Chulabhorn Royal Academy, 54 Kamphaeng Phet 6 Road, Lak Si, Bangkok10210, Thailand
- Research Center for Neuroscience, Institute of Molecular Biosciences, Mahidol University, Salaya, Nakornpathom 73170, Thailand
| | - Parichart Boontem
- Chulabhorn Graduate Institute, Chulabhorn Royal Academy, 54 Kamphaeng Phet 6 Road, Lak Si, Bangkok10210, Thailand
| | - Russel J. Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Jutamaad Satayavivad
- Chulabhorn Research Institute and Chulabhorn Graduate Institute, Chulabhorn Royal Academy, Bangkok10210, Thailand
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Scholtens RM, de Rooij SEJA, Vellekoop AE, Vrouenraets BC, van Munster BC. Preoperative CSF Melatonin Concentrations and the Occurrence of Delirium in Older Hip Fracture Patients: A Preliminary Study. PLoS One 2016; 11:e0167621. [PMID: 27936113 PMCID: PMC5147935 DOI: 10.1371/journal.pone.0167621] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 11/17/2016] [Indexed: 01/08/2023] Open
Abstract
Background Delirium is characterized by disturbances in circadian rhythm. Melatonin regulates our circadian rhythm. Our aim was to compare preoperative cerebrospinal fluid (CSF) melatonin levels in patients with and without postoperative delirium. Methods Prospective cohort study with hip fracture patients ≥ 65 years who were acutely admitted to the hospital for surgical treatment and received spinal anaesthesia. CSF was collected after cannulation, before administering anaesthetics. Melatonin was measured by radioimmunoassay (RIA). Data on delirium was obtained from medical and nursing records. Nurses screened every shift for delirium using the Delirium Observation Screening Scale (DOSS). If the DOSS was ≥3, a psychiatrist was consulted to diagnose possible delirium using the DSM-IV criteria. At admission, demographic data, medical history, and information on functional and cognitive status was obtained. Results Seventy-six patients met the inclusion criteria. Sixty patients were included in the analysis. Main reasons for exclusion were technical difficulties, insufficient CSF or exogenous melatonin use. Thirteen patients (21.7%) experienced delirium during hospitalisation. Baseline characteristics did not differ between patients with and without postoperative delirium. In patients with and without postoperative delirium melatonin levels were 12.88 pg/ml (SD 6.3) and 11.72 pg/ml (SD 4.5) respectively, p-value 0.47. No differences between patients with and without delirium were found in mean melatonin levels in analyses stratified for cognitive impairment or age. Conclusion Preoperative CSF melatonin levels did not differ between patients with and without postoperative delirium. This suggests that, if disturbances in melatonin secretion occur, these might occur after surgery due to postoperative inflammation.
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Affiliation(s)
- Rikie M. Scholtens
- Academic Medical Center, University of Amsterdam, Department of Internal Medicine, Geriatrics section, Amsterdam, The Netherlands
- * E-mail:
| | - Sophia E. J. A. de Rooij
- Academic Medical Center, University of Amsterdam, Department of Internal Medicine, Geriatrics section, Amsterdam, The Netherlands
- University Medical Center Groningen, University Centre for Geriatric Medicine, Groningen, The Netherlands
| | | | - Bart C. Vrouenraets
- Sint Lucas Andreas Hospital, Department of Surgery, Amsterdam, The Netherlands
| | - Barbara C. van Munster
- University Medical Center Groningen, University Centre for Geriatric Medicine, Groningen, The Netherlands
- Gelre Hospitals, Department of Geriatrics, Apeldoorn, The Netherlands
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45
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Melatoninergic System in Parkinson's Disease: From Neuroprotection to the Management of Motor and Nonmotor Symptoms. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:3472032. [PMID: 27829983 PMCID: PMC5088323 DOI: 10.1155/2016/3472032] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 09/25/2016] [Indexed: 12/13/2022]
Abstract
Melatonin is synthesized by several tissues besides the pineal gland, and beyond its regulatory effects in light-dark cycle, melatonin is a hormone with neuroprotective, anti-inflammatory, and antioxidant properties. Melatonin acts as a free-radical scavenger, reducing reactive species and improving mitochondrial homeostasis. Melatonin also regulates the expression of neurotrophins that are involved in the survival of dopaminergic neurons and reduces α-synuclein aggregation, thus protecting the dopaminergic system against damage. The unbalance of pineal melatonin synthesis can predispose the organism to inflammatory and neurodegenerative diseases such as Parkinson's disease (PD). The aim of this review is to summarize the knowledge about the potential role of the melatoninergic system in the pathogenesis and treatment of PD. The literature reviewed here indicates that PD is associated with impaired brain expression of melatonin and its receptors MT1 and MT2. Exogenous melatonin treatment presented an outstanding neuroprotective effect in animal models of PD induced by different toxins, such as 6-hydroxydopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), rotenone, paraquat, and maneb. Despite the neuroprotective effects and the improvement of motor impairments, melatonin also presents the potential to improve nonmotor symptoms commonly experienced by PD patients such as sleep and anxiety disorders, depression, and memory dysfunction.
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Reiter RJ, Mayo JC, Tan DX, Sainz RM, Alatorre-Jimenez M, Qin L. Melatonin as an antioxidant: under promises but over delivers. J Pineal Res 2016; 61:253-78. [PMID: 27500468 DOI: 10.1111/jpi.12360] [Citation(s) in RCA: 994] [Impact Index Per Article: 124.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/05/2016] [Indexed: 12/12/2022]
Abstract
Melatonin is uncommonly effective in reducing oxidative stress under a remarkably large number of circumstances. It achieves this action via a variety of means: direct detoxification of reactive oxygen and reactive nitrogen species and indirectly by stimulating antioxidant enzymes while suppressing the activity of pro-oxidant enzymes. In addition to these well-described actions, melatonin also reportedly chelates transition metals, which are involved in the Fenton/Haber-Weiss reactions; in doing so, melatonin reduces the formation of the devastatingly toxic hydroxyl radical resulting in the reduction of oxidative stress. Melatonin's ubiquitous but unequal intracellular distribution, including its high concentrations in mitochondria, likely aid in its capacity to resist oxidative stress and cellular apoptosis. There is credible evidence to suggest that melatonin should be classified as a mitochondria-targeted antioxidant. Melatonin's capacity to prevent oxidative damage and the associated physiological debilitation is well documented in numerous experimental ischemia/reperfusion (hypoxia/reoxygenation) studies especially in the brain (stroke) and in the heart (heart attack). Melatonin, via its antiradical mechanisms, also reduces the toxicity of noxious prescription drugs and of methamphetamine, a drug of abuse. Experimental findings also indicate that melatonin renders treatment-resistant cancers sensitive to various therapeutic agents and may be useful, due to its multiple antioxidant actions, in especially delaying and perhaps treating a variety of age-related diseases and dehumanizing conditions. Melatonin has been effectively used to combat oxidative stress, inflammation and cellular apoptosis and to restore tissue function in a number of human trials; its efficacy supports its more extensive use in a wider variety of human studies. The uncommonly high-safety profile of melatonin also bolsters this conclusion. It is the current feeling of the authors that, in view of the widely diverse beneficial functions that have been reported for melatonin, these may be merely epiphenomena of the more fundamental, yet-to-be identified basic action(s) of this ancient molecule.
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Affiliation(s)
- Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA.
| | - Juan C Mayo
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Dun-Xian Tan
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Rosa M Sainz
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Moises Alatorre-Jimenez
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Lilian Qin
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX, USA
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47
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Jockers R, Delagrange P, Dubocovich ML, Markus RP, Renault N, Tosini G, Cecon E, Zlotos DP. Update on melatonin receptors: IUPHAR Review 20. Br J Pharmacol 2016; 173:2702-25. [PMID: 27314810 DOI: 10.1111/bph.13536] [Citation(s) in RCA: 272] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/15/2016] [Accepted: 05/19/2016] [Indexed: 02/06/2023] Open
Abstract
Melatonin receptors are seven transmembrane-spanning proteins belonging to the GPCR superfamily. In mammals, two melatonin receptor subtypes exist - MT1 and MT2 - encoded by the MTNR1A and MTNR1B genes respectively. The current review provides an update on melatonin receptors by the corresponding subcommittee of the International Union of Basic and Clinical Pharmacology. We will highlight recent developments of melatonin receptor ligands, including radioligands, and give an update on the latest phenotyping results of melatonin receptor knockout mice. The current status and perspectives of the structure of melatonin receptor will be summarized. The physiological importance of melatonin receptor dimers and biologically important and type 2 diabetes-associated genetic variants of melatonin receptors will be discussed. The role of melatonin receptors in physiology and disease will be further exemplified by their functions in the immune system and the CNS. Finally, antioxidant and free radical scavenger properties of melatonin and its relation to melatonin receptors will be critically addressed.
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Affiliation(s)
- Ralf Jockers
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Paris, France
| | | | - Margarita L Dubocovich
- Department Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Science, University at Buffalo (SUNY), Buffalo, USA
| | - Regina P Markus
- Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | | | - Gianluca Tosini
- Neuroscience Institute and Department of Pharmacology and Toxicology, Morehouse School of Medicine, Atlanta, GA, USA
| | - Erika Cecon
- Inserm, U1016, Institut Cochin, Paris, France.,CNRS UMR 8104, Paris, France.,University Paris Descartes, Paris, France
| | - Darius P Zlotos
- Department of Pharmaceutical Chemistry, The German University in Cairo, New Cairo City, Cairo, Egypt
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48
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Tan DX, Manchester LC, Reiter RJ. CSF generation by pineal gland results in a robust melatonin circadian rhythm in the third ventricle as an unique light/dark signal. Med Hypotheses 2015; 86:3-9. [PMID: 26804589 DOI: 10.1016/j.mehy.2015.11.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 11/20/2015] [Indexed: 12/16/2022]
Abstract
Pineal gland is an important organ for the regulation of the bio-clock in all vertebrate species. Its major secretory product is melatonin which is considered as the chemical expression of darkness due to its circadian peak exclusively at night. Pineal melatonin can be either released into the blood stream or directly enter into the CSF of the third ventricle via the pineal recess. We have hypothesized that rather than the peripheral circulatory melatonin circadian rhythm serving as the light/dark signal, it is the melatonin rhythm in CSF of the third ventricle that serves this purpose. This is due to the fact that melatonin circadian rhythm in the CSF is more robust in terms of its extremely high concentration and its precise on/off peaks. Thus, extrapineal-generated melatonin or diet-derived melatonin which enters blood would not interfere with the bio-clock function of vertebrates. In addition, based on the relationship of the pineal gland to the CSF and the vascular structure of this gland, we also hypothesize that pineal gland is an essential player for CSF production. We feel it participates in both the formation and reabsorption of CSF. The mechanisms associated with these processes are reviewed and discussed in this brief review.
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Affiliation(s)
- Dun-Xian Tan
- Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, USA.
| | - Lucien C Manchester
- Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, USA
| | - Russel J Reiter
- Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, USA.
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Manchester LC, Coto-Montes A, Boga JA, Andersen LPH, Zhou Z, Galano A, Vriend J, Tan DX, Reiter RJ. Melatonin: an ancient molecule that makes oxygen metabolically tolerable. J Pineal Res 2015; 59:403-19. [PMID: 26272235 DOI: 10.1111/jpi.12267] [Citation(s) in RCA: 632] [Impact Index Per Article: 70.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 08/10/2015] [Indexed: 12/11/2022]
Abstract
Melatonin is remarkably functionally diverse with actions as a free radical scavenger and antioxidant, circadian rhythm regulator, anti-inflammatory and immunoregulating molecule, and as an oncostatic agent. We hypothesize that the initial and primary function of melatonin in photosynthetic cyanobacteria, which appeared on Earth 3.5-3.2 billion years ago, was as an antioxidant. The evolution of melatonin as an antioxidant by this organism was necessary as photosynthesis is associated with the generation of toxic-free radicals. The other secondary functions of melatonin came about much later in evolution. We also surmise that mitochondria and chloroplasts may be primary sites of melatonin synthesis in all eukaryotic cells that possess these organelles. This prediction is made on the basis that mitochondria and chloroplasts of eukaryotes developed from purple nonsulfur bacteria (which also produce melatonin) and cyanobacteria when they were engulfed by early eukaryotes. Thus, we speculate that the melatonin-synthesizing actions of the engulfed bacteria were retained when these organelles became mitochondria and chloroplasts, respectively. That mitochondria are likely sites of melatonin formation is supported by the observation that this organelle contains high levels of melatonin that are not impacted by blood melatonin concentrations. Melatonin has a remarkable array of means by which it thwarts oxidative damage. It, as well as its metabolites, is differentially effective in scavenging a variety of reactive oxygen and reactive nitrogen species. Moreover, melatonin and its metabolites modulate a large number of antioxidative and pro-oxidative enzymes, leading to a reduction in oxidative damage. The actions of melatonin on radical metabolizing/producing enzymes may be mediated by the Keap1-Nrf2-ARE pathway. Beyond its direct free radical scavenging and indirect antioxidant effects, melatonin has a variety of physiological and metabolic advantages that may enhance its ability to limit oxidative stress.
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Affiliation(s)
- Lucien C Manchester
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
| | - Ana Coto-Montes
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
| | - Jose Antonio Boga
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
| | - Lars Peter H Andersen
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
| | - Zhou Zhou
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
| | - Annia Galano
- Departamento de Quimica, Universidad Autonoma Metropolitana-Iztapalapa, Mexico DF, Mexico
| | - Jerry Vriend
- Department of Human Anatomy and Cell Biology, University of Manitoba, Winnipeg, MA, Canada
| | - Dun-Xian Tan
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
| | - Russel J Reiter
- Department of Cellular and Structural Biology, UT Health Science Center, San Antonio, TX, USA
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Tan DX, Manchester LC, Esteban-Zubero E, Zhou Z, Reiter RJ. Melatonin as a Potent and Inducible Endogenous Antioxidant: Synthesis and Metabolism. Molecules 2015; 20:18886-906. [PMID: 26501252 PMCID: PMC6332205 DOI: 10.3390/molecules201018886] [Citation(s) in RCA: 373] [Impact Index Per Article: 41.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 10/08/2015] [Accepted: 10/09/2015] [Indexed: 11/17/2022] Open
Abstract
Melatonin is a tryptophan-derived molecule with pleiotropic activities. It is present in almost all or all organisms. Its synthetic pathway depends on the species in which it is measured. For example, the tryptophan to melatonin pathway differs in plants and animals. It is speculated that the melatonin synthetic machinery in eukaryotes was inherited from bacteria as a result of endosymbiosis. However, melatonin's synthetic mechanisms in microorganisms are currently unknown. Melatonin metabolism is highly complex with these enzymatic processes having evolved from cytochrome C. In addition to its enzymatic degradation, melatonin is metabolized via pseudoenzymatic and free radical interactive processes. The metabolic products of these processes overlap and it is often difficult to determine which process is dominant. However, under oxidative stress, the free radical interactive pathway may be featured over the others. Because of the complexity of the melatonin degradative processes, it is expected that additional novel melatonin metabolites will be identified in future investigations. The original and primary function of melatonin in early life forms such as in unicellular organisms was as a free radical scavenger and antioxidant. During evolution, melatonin was selected as a signaling molecule to transduce the environmental photoperiodic information into an endocrine message in multicellular organisms and for other purposes as well. As an antioxidant, melatonin exhibits several unique features which differ from the classic antioxidants. These include its cascade reaction with free radicals and its capacity to be induced under moderate oxidative stress. These features make melatonin a potent endogenously-occurring antioxidant that protects organisms from catastrophic oxidative stress.
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Affiliation(s)
- Dun-Xian Tan
- Department of Cellular and Structural Biology, Health Science Center, University of Texas, San Antonio, TX 78229, USA.
| | - Lucien C Manchester
- Department of Cellular and Structural Biology, Health Science Center, University of Texas, San Antonio, TX 78229, USA.
| | - Eduardo Esteban-Zubero
- Department of Cellular and Structural Biology, Health Science Center, University of Texas, San Antonio, TX 78229, USA.
| | - Zhou Zhou
- Department of Cellular and Structural Biology, Health Science Center, University of Texas, San Antonio, TX 78229, USA.
| | - Russel J Reiter
- Department of Cellular and Structural Biology, Health Science Center, University of Texas, San Antonio, TX 78229, USA.
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