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Singh SK, Durazzo A, Lucarini M, Valles SL, Poeggeler B. Editorial: Antioxidant and neuroprotective potential of alternative and complementary therapeutic approaches against Alzheimer's disease. Front Pharmacol 2023; 14:1289979. [PMID: 37927609 PMCID: PMC10621970 DOI: 10.3389/fphar.2023.1289979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 10/10/2023] [Indexed: 11/07/2023] Open
Affiliation(s)
| | | | | | - Soraya L. Valles
- Department of Physiology, School of Medicine, University of Valencia, Valencia, Spain
| | - Burkhard Poeggeler
- Faculty of Biology and Psychology, Johann-Friedrich-Blumenbach-Institute for Zoology and Anthropology, Georg August University Göttingen, Göttingen, Germany
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2
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Poeggeler B, Singh SK, Sambamurti K, Pappolla MA. Nitric Oxide as a Determinant of Human Longevity and Health Span. Int J Mol Sci 2023; 24:14533. [PMID: 37833980 PMCID: PMC10572643 DOI: 10.3390/ijms241914533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023] Open
Abstract
The master molecular regulators and mechanisms determining longevity and health span include nitric oxide (NO) and superoxide anion radicals (SOR). L-arginine, the NO synthase (NOS) substrate, can restore a healthy ratio between the dangerous SOR and the protective NO radical to promote healthy aging. Antioxidant supplementation orchestrates protection against oxidative stress and damage-L-arginine and antioxidants such as vitamin C increase NO production and bioavailability. Uncoupling of NO generation with the appearance of SOR can be induced by asymmetric dimethylarginine (ADMA). L-arginine can displace ADMA from the site of NO formation if sufficient amounts of the amino acid are available. Antioxidants such as ascorbic acids can scavenge SOR and increase the bioavailability of NO. The topics of this review are the complex interactions of antioxidant agents with L-arginine, which determine NO bioactivity and protection against age-related degeneration.
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Affiliation(s)
- Burkhard Poeggeler
- Department of Physiology, Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, Faculty of Biology and Psychology, Georg August University Göttingen, Zappenburg 2, D-38524 Sassenburg, Germany
| | - Sandeep Kumar Singh
- Indian Scientific Education and Technology Foundation, Lucknow 226002, India;
| | - Kumar Sambamurti
- Department of Neurobiology, Medical University of South Carolina, 173 Ashley Avenue, BSB 403, Charleston, SC 29425, USA;
| | - Miguel A. Pappolla
- Department of Neurology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA;
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Poeggeler B, Singh SK, Sambamurti K, Pappolla MA. Tryptophan in Nutrition and Health 2.0. Int J Mol Sci 2023; 24:ijms24087112. [PMID: 37108272 PMCID: PMC10138358 DOI: 10.3390/ijms24087112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
This editorial summarizes the eight articles that have been collected for the Special Issue entitled "Tryptophan in Nutrition and Health 2 [...].
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Affiliation(s)
- Burkhard Poeggeler
- Department of Physiology, Johann-Friedrich-Blumenbach-Institute for Zoology and Anthropology, Faculty of Biology Georg August University Göttingen, Göttingen and Goettingen Research Campus, Am Türmchen 3, D-33332 Gütersloh, Germany
| | - Sandeep Kumar Singh
- Indian Scientific Education and Technology Foundation, Lucknow 226002, India
| | - Kumar Sambamurti
- Department of Neurobiology, Medical University of South Carolina, 173 Ashley Avenue, BSB 403, Charleston, SC 29425, USA
| | - Miguel Angelo Pappolla
- Department of Neurology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA
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4
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Singh SK, Balendra V, Obaid AA, Esposto J, Tikhonova MA, Gautam NK, Poeggeler B. Copper-Mediated β-Amyloid Toxicity and its Chelation Therapy in Alzheimer's Disease. Metallomics 2022; 14:6554256. [PMID: 35333348 DOI: 10.1093/mtomcs/mfac018] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Accepted: 03/08/2022] [Indexed: 01/10/2023]
Abstract
The link between bio-metals, Alzheimer's disease (AD), and its associated protein, amyloid-β (Aβ) is very complex and one of the most studied aspects currently. Alzheimer's disease, a progressive neurodegenerative disease, is proposed to occurs due to the misfolding and aggregation of Aβ. Dyshomeostasis of metal ions and their interaction with Aβ has largely been implicated in AD. Copper plays a crucial role in amyloid-β toxicity and AD development potentially occurs through direct interaction with the copper-binding motif of APP and different amino acid residues of Aβ. Previous reports suggest that high levels of copper accumulation in the AD brain result in modulation of toxic Aβ peptide levels, implicating the role of copper in the pathophysiology of AD. In this review, we explore the possible mode of copper ion interaction with Aβ which accelerates the kinetics of fibril formation and promote amyloid-β mediated cell toxicity in Alzheimer's disease and the potential use of various copper chelators in the prevention of copper-mediated Aβ toxicity.
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Affiliation(s)
- Sandeep Kumar Singh
- Indian Scientific Education and Technology Foundation, Lucknow-226002, India
| | - Vyshnavy Balendra
- Saint James School of Medicine, Park Ridge, Illinois, United States of America 60068
| | - Ahmad A Obaid
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Josephine Esposto
- Department of Environmental and Life Sciences, Trent University, Peterborough, Ontario, CanadaK9L 0G2
| | - Maria A Tikhonova
- Laboratory of the Experimental Models of Neurodegenerative Processes, Scientific Research Institute of Neurosciences and Medicine; Timakov st., 4, Novosibirsk, 630117, Russia
| | - Naveen Kumar Gautam
- Department of Urology and Renal Transplantation, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Raebareli Road, Lucknow 226014, Uttar Pradesh, India
| | - Burkhard Poeggeler
- Johann-Friedrich-Blumenbach-Institute for Zoology & Anthropology, Faculty of Biology and Psychology, Georg-August-University of Göttingen, Am Türmchen 3,33332 Gütersloh, Germany
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Poeggeler B, Robenek H, Pappolla MA. Editorial: Pharmacology of L-Arginine and L-Arginine-Rich Food. Front Pharmacol 2021; 12:743788. [PMID: 34413781 PMCID: PMC8370829 DOI: 10.3389/fphar.2021.743788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 07/22/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Burkhard Poeggeler
- Johann-Friedrich-Blumenbach-Institute for Zoology and Anthropology, Faculty of Biology and Psychology, Georg August University Göttingen, Göttingen and Goettingen Research Campus, Göttingen, Germany
| | - Horst Robenek
- Department of Neurology, University of Texas Medical Branch, University Boulevard, Galveston, TX, United States
| | - Miguel A Pappolla
- Leibniz-Institut für Arterioskleroseforschung, Universitätsklinikum Münster, Münster, Germany
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Pappolla MA, Perry G, Fang X, Zagorski M, Sambamurti K, Poeggeler B. Indoles as essential mediators in the gut-brain axis. Their role in Alzheimer's disease. Neurobiol Dis 2021; 156:105403. [PMID: 34087380 DOI: 10.1016/j.nbd.2021.105403] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 05/05/2021] [Accepted: 05/21/2021] [Indexed: 02/07/2023] Open
Abstract
Sporadic late-onset Alzheimer's disease (AD) is the most frequent cause of dementia associated with aging. Due to the progressive aging of the population, AD is becoming a healthcare burden of unprecedented proportions. Twenty years ago, it was reported that some indole molecules produced by the gut microbiota possess essential biological activities, including neuroprotection and antioxidant properties. Since then, research has cemented additional characteristics of these substances, including anti-inflammatory, immunoregulatory, and amyloid anti-aggregation features. Herein, we summarize the evidence supporting an integrated hypothesis that some of these substances can influence the age of onset and progression of AD and are central to the symbiotic relationship between intestinal microbes and the brain. Studies have shown that some of these substances' activities result from interactions with biologically conserved pathways and with genetic risk factors for AD. By targeting multiple pathologic mechanisms simultaneously, certain indoles may be excellent candidates to ameliorate neurodegeneration. We propose that management of the microbiota to induce a higher production of neuroprotective indoles (e.g., indole propionic acid) will promote brain health during aging. This area of research represents a new therapeutic paradigm that could add functional years of life to individuals who would otherwise develop dementia.
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Affiliation(s)
- Miguel A Pappolla
- University of Texas Medical Branch, Department of Neurology, Galveston, TX, United States of America.
| | - George Perry
- University of Texas at San Antonio, Department of Biology, San Antonio, TX, United States of America
| | - Xiang Fang
- University of Texas Medical Branch, Department of Neurology, Galveston, TX, United States of America
| | - Michael Zagorski
- Case Western Reserve University, Department of Chemistry, Cleveland, United States of America
| | - Kumar Sambamurti
- Medical University of South Carolina, Department of Neurobiology, Charleston, SC, United States of America
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Pappolla M, Matsubara E, Vidal R, Pacheco-Quinto J, Poeggeler B, Zagorski M, Sambamurti K. Melatonin Treatment Enhances Aβ Lymphatic Clearance in a Transgenic Mouse Model of Amyloidosis. Curr Alzheimer Res 2018; 15:637-642. [DOI: 10.2174/1567205015666180411092551] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 01/05/2018] [Accepted: 01/31/2018] [Indexed: 11/22/2022]
Abstract
Background:
It has been postulated that inadequate clearance of the amyloid β protein (Aβ)
plays an important role in the accumulation of Aβ in sporadic late onset Alzheimer's disease (AD).
While the blood brain barrier (BBB) has taken the center stage in processes involving Aβ clearance, little
information is available about the role of the lymphatic system. We previously reported that Aβ is
cleared through the lymphatic system. We now assessed lymphatic Aβ clearance by treating a mouse
model of AD amyloidosis with melatonin, an Aβ aggregation inhibitor and immuno-regulatory neurohormone.
Objective:
To confirm and expand our initial finding that Aβ is cleared through the lymphatic system.
Lymphatic clearance of metabolic and cellular “waste” products from the brain into the peripheral lymphatic
system has been known for a long time. However, except for our prior report, there is no additional
experimental data published about Aβ being cleared into peripheral lymph nodes.
Methods:
For these experiments, we used a transgenic mouse model (Tg2576) that over-expresses a mutant
form of the Aβ precursor protein (APP) in the brain. We examined levels of Aβ in plasma and in
lymph nodes of transgenic mice as surrogate markers of vascular and lymphatic clearance, respectively.
Aβ levels were also measured in the brain and in multiple tissues.
Results:
Clearance of Aβ peptides through the lymphatic system was confirmed in this study. Treatment
with melatonin led to the following changes: 1-A statistically significant increase in soluble monomeric
Aβ40 and an increasing trend in Aβ42 in cervical and axillary lymph nodes of treated mice. 2-
Statistically significant decreases in oligomeric Aβ40 and a decreasing trend Aβ42 in the brain.
Conclusion:
The data expands on our prior report that the lymphatic system participates in Aβ clearance
from the brain. We propose that abnormalities in Aβ clearance through the lymphatic system may contribute
to the development of cerebral amyloidosis. Melatonin and related indole molecules (i.e., indole-
3-propionic acid) are known to inhibit Aβ aggregation although they do not reverse aggregated Aβ or
amyloid fibrils. Therefore, these substances should be further explored in prevention trials for delaying
the onset of cognitive impairment in high risk populations.
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Affiliation(s)
- M.A. Pappolla
- Department of Neurology, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, United States
| | - E. Matsubara
- Faculty of Medicine, Oita University, 1-1 Idaigaoka, Hasama, Yufu, Oita 879-5593, Japan
| | - R. Vidal
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, 635 Barnhill Dr., MSB A176, Indianapolis, IN 46202, United States
| | - J. Pacheco-Quinto
- Biomedical Research Institute of New Jersey, Mid Atlantic Neonatology Associates and Atlantic Health System, Morristown, NJ 07960, United States
| | - B. Poeggeler
- Johann-Friedrich-Blumenbach Institute of Zoology and Anthropology, Faculty of Biology and Psychology, Georg-August-Universitat Gottingen, Am Turmchen 3, D-33332 Gutersloh, Germany
| | - M. Zagorski
- Department of Chemistry, Case Western University 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - K. Sambamurti
- Department of Neurosciences, Medical University of South, Carolina, 173 Ashley Avenue, BSB 403, Charleston, SC 29425, United States
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Henz D, Schöllhorn WI, Poeggeler B. Mobile Phone Chips Reduce Increases in EEG Brain Activity Induced by Mobile Phone-Emitted Electromagnetic Fields. Front Neurosci 2018; 12:190. [PMID: 29670503 PMCID: PMC5893900 DOI: 10.3389/fnins.2018.00190] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 03/08/2018] [Indexed: 11/16/2022] Open
Abstract
Recent neurophysiological studies indicate that exposure to electromagnetic fields (EMFs) generated by mobile phone radiation can exert effects on brain activity. One technical solution to reduce effects of EMFs in mobile phone use is provided in mobile phone chips that are applied to mobile phones or attached to their surfaces. To date, there are no systematical studies on the effects of mobile phone chip application on brain activity and the underlying neural mechanisms. The present study investigated whether mobile phone chips that are applied to mobile phones reduce effects of EMFs emitted by mobile phone radiation on electroencephalographic (EEG) brain activity in a laboratory study. Thirty participants volunteered in the present study. Experimental conditions (mobile phone chip, placebo chip, no chip) were set up in a randomized within-subjects design. Spontaneous EEG was recorded before and after mobile phone exposure for two 2-min sequences at resting conditions. During mobile phone exposure, spontaneous EEG was recorded for 30 min during resting conditions, and 5 min during performance of an attention test (d2-R). Results showed increased activity in the theta, alpha, beta and gamma bands during EMF exposure in the placebo and no chip conditions. Application of the mobile phone chip reduced effects of EMFs on EEG brain activity and attentional performance significantly. Attentional performance level was maintained regarding number of edited characters. Further, a dipole analysis revealed different underlying activation patterns in the chip condition compared to the placebo chip and no chip conditions. Finally, a correlational analysis for the EEG frequency bands and electromagnetic high-frequency (HF) emission showed significant correlations in the placebo chip and no chip condition for the theta, alpha, beta, and gamma bands. In the chip condition, a significant correlation of HF with the theta and alpha bands, but not with the beta and gamma bands was shown. We hypothesize that a reduction of EEG beta and gamma activation constitutes the key neural mechanism in mobile phone chip use that supports the brain to a degree in maintaining its natural activity and performance level during mobile phone use.
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Affiliation(s)
- Diana Henz
- Institute of Sports Science, Johannes Gutenberg University Mainz, Mainz, Germany
| | | | - Burkhard Poeggeler
- Johann-Friedrich-Blumenbach-Institute for Zoology and Anthropology, Faculty of Biology and Psychology, Georg-August-University Göttingen, Göttingen, Germany
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Rosselin M, Poeggeler B, Durand G. Nitrone Derivatives as Therapeutics: From Chemical Modification to Specific-targeting. Curr Top Med Chem 2017; 17:2006-2022. [PMID: 28260508 DOI: 10.2174/1568026617666170303115324] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 07/19/2016] [Accepted: 07/19/2016] [Indexed: 11/22/2022]
Abstract
Nitrones have been extensively used for the detection of transient free radicals using electron paramagnetic resonance. Since the mid-80's, nitrones have also been widely used as protective agents against oxidative stress in several biological models. Due to the high potency of nitrones, there has been extensive research on the development of derivatives with improved biological and spin trapping properties as well as enhanced intra-cellular compartmentalization. The chemical and pharmacological properties of nitrones depend mainly on the connectivity as well as on the nature and the position of the substituents on the nitrone group. Therefore, novel bioactive molecules have been designed and the development of specific nitrone derivatives is aimed at providing new therapeutic approaches and perspectives in prevention, treatment and rehabilitation. This review focuses on the effects that are exerted by the most promising nitrone antioxidants that are available. A comprehensive description of the unique molecular mechanism and mediators that are targeted by these compounds is given to guide and enable novel and successful approaches to the treatment of a broad spectrum of diseases associated with stress and aging. New promising nitrone compounds are now available for further development by translational medicine that exert superior bioactivity and efficacy.
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Affiliation(s)
- Marie Rosselin
- Institut des Biomolecules Max Mousseron (IBMM), UMR 5247 CNRS-Universite Montpellier-ENSCM; Universite d'Avignon, Equipe Chimie Bioorganique et Systemes Amphiphiles, 301 rue Baruch de Spinoza BP 21239, 84916 Avignon Cedex 9, France
| | - Burkhard Poeggeler
- Abteilung Stoffwechselphysiologie, Georg-August Universitat Gottingen and Goettingen Research Campus, Am Türmchen 3, 33332 Gutersloh. Germany
| | - Gregory Durand
- Institut des Biomolecules Max Mousseron (IBMM), UMR 5247 CNRS-Universite Montpellier- ENSCM; Universite d'Avignon, Equipe Chimie Bioorganique et Systemes Amphiphiles, 301 rue Baruch de Spinoza BP 21239, 84916 Avignon Cedex 9, France
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Poeggeler B, Reiter RJ, Hardeland R, Tan DX, Barlow-Walden LR. Melatonin and structurally-related, endogenous indoles act as potent electron donors and radical scavengers in vitro. Redox Rep 2016; 2:179-84. [DOI: 10.1080/13510002.1996.11747046] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Abstract
The paper by Merchant et al. demonstrates that the pharmacokinetic profile of melatonin differs in preterm infants from that of adults. The findings of this study can guide the necessary future preventive and therapeutic clinical trials on melatonin in preterm infants. These studies are urgently needed to further evaluate the protective potential of melatonin in preterm infants. Melatonin acts as a potent endogenous antioxidant agent that antagonizes oxidative stress, and melatonin replacement therapy could thereby prevent the development of many disorders and diseases that can afflict preterm infants such as sepsis, asphyxia, respiratory distress or surgical complications. Since preterm infants are melatonin deficient, administration of the compound may provide the necessary levels to assure their health and well-being. Pharmacokinetic data such as those provided in the evaluated paper are necessary to establish safe and efficient melatonin treatment regimens in this highly susceptible population.
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Affiliation(s)
- Burkhard Poeggeler
- QUIRIS Healthcare Germany, Am Kreuzkamp 5-7, D-33334 Gütersloh, Germany.
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Pappolla M, Sambamurti K, Vidal R, Pacheco-Quinto J, Poeggeler B, Matsubara E. Evidence for lymphatic Aβ clearance in Alzheimer's transgenic mice. Neurobiol Dis 2014; 71:215-9. [PMID: 25102344 DOI: 10.1016/j.nbd.2014.07.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 07/23/2014] [Accepted: 07/28/2014] [Indexed: 11/26/2022] Open
Abstract
Evidence has shown that lymphatic drainage contributes to removal of debris from the brain but its role in the accumulation of amyloid β peptides (Aβ) has not been demonstrated. We examined the levels of various forms of Aβ in the brain, plasma and lymph nodes in a transgenic model of Alzheimer's disease (AD) at different ages. Herein, we report on the novel finding that Aβ is present in the cervical and axillary lymph nodes of AD transgenic mice and that Aβ levels in lymph nodes increase over time, mirroring the increase of Aβ levels observed in the brain. Aβ levels in lymph nodes were significantly higher than in plasma. At age 15.5months, there was a significant increase of monomeric soluble Aβ40 (p=0.003) and Aβ42 (p=0.05) in the lymph nodes over the baseline values measured at 6months of age. In contrast, plasma levels of Aβ40 showed no significant changes (p=0.68) and plasma levels Aβ42 significantly dropped (p=0.02) at the same age. Aβ concentration was low to undetectable in splenic lymphoid tissue and several other control tissues including heart, lung, liver, kidneys and intestine of the same animals, strongly suggesting that Aβ peptides in lymph nodes are derived from the brain.
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Affiliation(s)
- Miguel Pappolla
- Department of Neurology, University of Texas Medical Branch, 301 University Boulevard Galveston, TX 77555, United States.
| | - Kumar Sambamurti
- Department of Neurosciences, Medical University of South Carolina, 173 Ashley Avenue, BSB 403, Charleston, SC 29425, United States
| | - Ruben Vidal
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, 635 Barnhill Dr., MSB A176, Indianapolis, IN 46202, United States
| | - Javier Pacheco-Quinto
- Biomedical Research Institute of New Jersey, Mid Atlantic Neonatology Associates and Atlantic Health System, Morristown, NJ 07960, United States
| | - Burkhard Poeggeler
- Faculty of Biology and Psychology, Georg-August-Universität Göttingen, Germany
| | - Etsuro Matsubara
- Department of Neurology, Institute of Brain Science, Hirosaki University Graduate School of Medicine, Aomori, Japan
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Abstract
A new flavone sulfonic acid 1 named niruriflavone was isolated from the 70% ethanolic extract of the whole plant of Phyllanthus niruri (Euphorbiaceae), together with 6,10,14-trimethyl-2- pentadecanone, hypophyllanthin, gallic acid, brevifolin carboxylic acid, methyl brevifolin carboxylate, isoquercetin, quercetin-3-O-β -D-glucopyranosyl(1→ 4)-α-rhamnopyranoside, corilagin, and isocorilagin, whose structures were determined by spectroscopic methods and comparison with published data. In an ABTS cation radical reduction assay, niruriflavone (1) exhibited potent radical scavenging properties. A biological test system based on bioluminescence of the dinoflagellate Lingulodinium polyedrum did not reveal any prooxidant properties of 1 at 50 μM.
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Affiliation(s)
- N. N. Than
- Department of Chemistry, University of Yangon, P.O. 11041, Yangon, Myanmar
| | - S. Fotso
- Department of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstraße 2, D-37077 Göttingen, Germany
| | - B. Poeggeler
- Department of Zoology and Anthropology, University of Göttingen, Berliner Straße 28, D-37073 Göttingen, Germany
| | - R. Hardeland
- Department of Zoology and Anthropology, University of Göttingen, Berliner Straße 28, D-37073 Göttingen, Germany
| | - H. Laatsch
- Department of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstraße 2, D-37077 Göttingen, Germany
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Ressmeyer AR, Mayo JC, Zelosko V, Sáinz RM, Tan DX, Poeggeler B, Antolín I, Zsizsik BK, Reiter RJ, Hardeland R. Antioxidant properties of the melatonin metabolite N1-acetyl-5-methoxykynuramine (AMK): scavenging of free radicals and prevention of protein destruction. Redox Rep 2013; 8:205-13. [PMID: 14599344 DOI: 10.1179/135100003225002709] [Citation(s) in RCA: 172] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In numerous experimental systems, the neurohormone melatonin has been shown to protect against oxidative stress, an effect which appears to be the result of a combination of different actions. In this study, we have investigated the possible contribution to radical scavenging by substituted kynuramines formed from melatonin via pyrrole ring cleavage. N1-Acetyl-5-methoxykynuramine (AMK), a metabolite deriving from melatonin by mechanisms involving free radicals, exhibits potent antioxidant properties exceeding those of its direct precursor N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK) and its analog N1-acetylkynuramine (AK). Scavenging of hydroxyl radicals was demonstrated by competition with ABTS in a Fenton reaction system at pH 5 and by competition with DMSO in a hemin-catalyzed H2O2 system at pH 8. Under catalysis by hemin, oxidation of AMK was accompanied by the emission of chemiluminescence. AMK was a potent reductant of ABTS cation radicals, but, in the absence of catalysts, a poor scavenger of superoxide anions. In accordance with the latter observation, AMK was fairly stable in a pH 8 H2O2 system devoid of hemin. Contrary to AFMK, AMK was easily oxidized in a reaction mixture generating carbonate radicals. In an oxidative protein destruction assay based on peroxyl radical formation, AMK proved to be highly protective. No prooxidant properties of AMK were detected in a sensitive biological test system based on light emission by the bioluminescent dinoflagellate Lingulodinium polyedrum. AMK may contribute to the antioxidant properties of the indolic precursor melatonin.
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Affiliation(s)
- Anna-Rebekka Ressmeyer
- Institut für Zoologie, Anthropologie und Entwicklungsbiologie, Universität Göttingen, Göttingen, Germany
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Behrends A, Hardeland R, Ness H, Grube S, Poeggeler B, Haldar C. Photocatalytic actions of the pesticide metabolite 2-hydroxyquinoxaline: destruction of antioxidant vitamins and biogenic amines – implications of organic redox cycling. Redox Rep 2013; 9:279-88. [PMID: 15606981 DOI: 10.1179/135100004225006759] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Toxicity of the pesticide quinalphos may comprise secondary, delayed effects by its main metabolite 2-hydroxyquinoxaline (HQO). We demonstrate that HQO can destroy photocatalytically vitamins C and E, catecholamines, serotonin, melatonin, the melatonin metabolite AMK (N(1)-acetyl-5-methoxykynuramine), and unsubstituted and substituted anthranilic acids when exposed to visible light. In order to avoid HQO-independent ascorbate oxidation by light and to exclude actions by hydroxyl radicals, experiments on this vitamin were carried out in ethanolic solutions. Other substances tested (vitamin E, melatonin, anthranilic acids) were also photocatalytically destroyed by HQO in ethanol. After product analyses had indicated that HQO was not, or only poorly, degraded in the light, despite its catalytic action on other compounds, we followed directly the time course of HQO and ascorbate concentrations in ethanol. While ascorbate was largely destroyed, no change in HQO was demonstrable within 2 h of incubation. Destruction was not prevented by the singlet oxygen quencher DABCO. Obviously, HQO is capable of undergoing a process of organic redox cycling, perhaps via an intermediate quinoxaline-2-oxyl radical. Health problems from HQO intoxication may not only arise from the loss of valuable biomolecules, such as antioxidant vitamins and biogenic amines, but also from the formation of potentially toxic products. Dimerization and oligomerization are involved in several oxidation processes catalyzed by HQO, especially in the indoleamines, in dopamine, and presumably also in vitamin E. Melatonin oxidation by HQO did not only lead to the well-known - and usually protective - metabolite AFMK (N(1)-acetyl-N(2)-formyl-5-methoxykynuramine), but also to a high number of additional products, among them dimers and trimers. DABCO did not prevent melatonin destruction, but changed the spectrum of products. Serotonin was preferentially converted to a dimer, which can further oligomerize. Several indole dimers are known to be highly neurotoxic, as well as oxidation products formed from catecholamines via the adrenochrome/noradrenochrome pathway. Destruction of melatonin may cause deficiencies in circadian physiology, in immune functions and in antioxidative protection.
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Affiliation(s)
- Andreas Behrends
- Institut für Zoologie, Anthropologie und Entwicklungsbiologie, Universität Göttingen, Göttingen, Germany
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Hardeland R, Poeggeler B. Melatonin and synthetic melatonergic agonists: actions and metabolism in the central nervous system. Cent Nerv Syst Agents Med Chem 2013; 12:189-216. [PMID: 22640220 DOI: 10.2174/187152412802430129] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 04/19/2012] [Accepted: 05/09/2012] [Indexed: 01/23/2023]
Abstract
The CNS is both source and target of melatonin. This methoxyindole formed in the pineal gland is also produced in other CNS regions and additionally enters the brain by uptake from the circulation as well as via the pineal recess. The mammalian circadian pacemaker, the suprachiasmatic nucleus (SCN), not only controls the pineal, but also receives a feedback information on darkness. Two G protein-coupled melatonin receptors, MT1 and MT2, are responsible for the transduction of many melatonergic actions. High receptor densities are especially found in the SCN, but their presence at lower expression levels in other areas is functionally important. Various metabolites and analogs are formed in the CNS, such as N-acetylserotonin, 5-methoxytryptamine, 5-methoxytryptophol, 5-methoxylated kynuramines, and even 6-sulfatoxymelatonin. The chronobiological effects of melatonin go beyond the resetting of a single circadian oscillator. They contribute to phase relationships between oscillatory subsets and are required for robust rhythm amplitudes. CNS effects of melatonin comprise sleep initiation, antiexcitatory, antiepileptic, antinociceptive, anxiolytic, proneurotrophic, antiinflammatory, antioxidant and other neuroprotective actions. The role as a sleep-promoting compound, which is limited by its short half-life in the circulation, has led to the development of controlled-release formulations and of various synthetic agonists, such as ramelteon, agomelatine, tasimelteon, TIK-301, UCM765 and UCM924. Their differences concerning receptor affinities, preferences for receptor subtypes, and pharmacokinetics are discussed, as well as additional antidepressive actions of agomelatine and TIK-301 based on properties as antagonists of the serotonergic 5-HT2C receptor. Indirect antidepressive effects by melatonergic drugs are largely explained by circadian readjustments.
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Affiliation(s)
- R Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Goettingen, Goettingen, Germany.
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Knuever J, Poeggeler B, Gáspár E, Klinger M, Hellwig-Burgel T, Hardenbicker C, Tóth BI, Bíró T, Paus R. Thyrotropin-releasing hormone controls mitochondrial biology in human epidermis. J Clin Endocrinol Metab 2012; 97:978-86. [PMID: 22259067 DOI: 10.1210/jc.2011-1096] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Mitochondrial capacity and metabolic potential are under the control of hormones, such as thyroid hormones. The most proximal regulator of the hypothalamic-pituitary-thyroid (HPT) axis, TRH, is the key hypothalamic integrator of energy metabolism via its impact on thyroid hormone secretion. OBJECTIVE Here, we asked whether TRH directly modulates mitochondrial functions in normal, TRH-receptor-positive human epidermis. METHODS Organ-cultured human skin was treated with TRH (5-100 ng/ml) for 12-48 h. RESULTS TRH significantly increased epidermal immunoreactivity for the mitochondria-selective subunit I of respiratory chain complex IV (MTCO1). This resulted from an increased MTCO1 transcription and protein synthesis and a stimulation of mitochondrial biogenesis as demonstrated by transmission electron microscopy and TRH-enhanced mitochondrial DNA synthesis. TRH also significantly stimulated the transcription of several other mitochondrial key genes (TFAM, HSP60, and BMAL1), including the master regulator of mitochondrial biogenesis (PGC-1α). TRH significantly enhanced mitochondrial complex I and IV enzyme activity and enhanced the oxygen consumption of human skin samples, which shows that the stimulated mitochondria are fully vital because the main source for cellular oxygen consumption is mitochondrial endoxidation. CONCLUSIONS These findings identify TRH as a potent, novel neuroendocrine stimulator of mitochondrial activity and biogenesis in human epidermal keratinocytes in situ. Thus, human epidermis offers an excellent model for dissecting neuroendocrine controls of human mitochondrial biology under physiologically relevant conditions and for exploring corresponding clinical applications.
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Affiliation(s)
- Jana Knuever
- Department of Dermatology, University of Luebeck, Ratzeburger Allee 160, D-23538 Luebeck, Germany
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Fuhrberg B, Hardeland R, Poeggeler B, Behrmann C. Dramatic Rises of Melatonin and 5-Methoxytryptamine in Gonyaulax Exposed to Decreased Temperature. BIOL RHYTHM RES 2010. [DOI: 10.1076/brhm.28.1.144.12978] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Burkhardt S, Meyer TJ, Hardeland R, Poeggeler B, Fuhrberg B, Balzer I. Requirement of Indoleamines and a V-type Proton ATPase for the Expression of the Circadian Glow Rhythm in Gonyaulax polyedra. BIOL RHYTHM RES 2010. [DOI: 10.1076/brhm.28.1.151.12973] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Durand G, Poeggeler B, Ortial S, Polidori A, Villamena FA, Böker J, Hardeland R, Pappolla MA, Pucci B. Amphiphilic Amide Nitrones: A New Class of Protective Agents Acting as Modifiers of Mitochondrial Metabolism. J Med Chem 2010; 53:4849-61. [DOI: 10.1021/jm100212x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Grégory Durand
- Laboratoire de Chimie BioOrganique et des Systèmes Moléculaires Vectoriels, Université d’Avignon et des Pays de Vaucluse, Faculté des Sciences, 33 Rue Louis Pasteur, 84000 Avignon, France
| | - Burkhard Poeggeler
- Department of Dermatology, University of Luebeck, Ratzeburger Allee 160, D-23538 Luebeck, Germany
- Abteilung fuer Stoffwechselphysiologie, Institut fuer Zoologie, Anthropologie und Entwicklungsbiologie der Georg August Universität Göttingen, Berliner Strasse 28, D-37073 Göttingen, Germany
| | - Stéphanie Ortial
- Laboratoire de Chimie BioOrganique et des Systèmes Moléculaires Vectoriels, Université d’Avignon et des Pays de Vaucluse, Faculté des Sciences, 33 Rue Louis Pasteur, 84000 Avignon, France
| | - Ange Polidori
- Laboratoire de Chimie BioOrganique et des Systèmes Moléculaires Vectoriels, Université d’Avignon et des Pays de Vaucluse, Faculté des Sciences, 33 Rue Louis Pasteur, 84000 Avignon, France
| | - Frederick A. Villamena
- Department of Pharmacology and Center for Biomedical EPR Spectroscopy and Imaging, The Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Jutta Böker
- Abteilung fuer Stoffwechselphysiologie, Institut fuer Zoologie, Anthropologie und Entwicklungsbiologie der Georg August Universität Göttingen, Berliner Strasse 28, D-37073 Göttingen, Germany
| | - Rüdiger Hardeland
- Abteilung fuer Stoffwechselphysiologie, Institut fuer Zoologie, Anthropologie und Entwicklungsbiologie der Georg August Universität Göttingen, Berliner Strasse 28, D-37073 Göttingen, Germany
| | - Miguel A. Pappolla
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Bernard Pucci
- Laboratoire de Chimie BioOrganique et des Systèmes Moléculaires Vectoriels, Université d’Avignon et des Pays de Vaucluse, Faculté des Sciences, 33 Rue Louis Pasteur, 84000 Avignon, France
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Poeggeler B, Sambamurti K, Siedlak SL, Perry G, Smith MA, Pappolla MA. A novel endogenous indole protects rodent mitochondria and extends rotifer lifespan. PLoS One 2010; 5:e10206. [PMID: 20421998 PMCID: PMC2858081 DOI: 10.1371/journal.pone.0010206] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Accepted: 03/04/2010] [Indexed: 12/31/2022] Open
Abstract
Aging is a multi-factorial process, however, it is generally accepted that reactive oxygen species (ROS) are significant contributors. Mitochondria are important players in the aging process because they produce most of the cellular ROS. Despite the strength of the free-radical hypothesis, the use of free radical scavengers to delay aging has generated mixed results in vertebrate models, and clinical evidence of efficacy is lacking. This is in part due to the production of pro-oxidant metabolites by many antioxidants while scavenging ROS, which counteract their potentially beneficial effects. As such, a more effective approach is to enhance mitochondrial metabolism by reducing electron leakage with attendant reduction of ROS generation. Here, we report on the actions of a novel endogenous indole derivative, indolepropionamide (IPAM), which is similar in structure to melatonin. Our results suggest that IPAM binds to the rate-limiting component of oxidative phosphorylation in complex I of the respiratory chain and acts as a stabilizer of energy metabolism, thereby reducing ROS production. IPAM reversed the age-dependent decline of mitochondrial energetic capacity and increased rotifer lifespan, and it may, in fact, constitute a novel endogenous anti-aging substance of physiological importance.
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Affiliation(s)
| | - Kumar Sambamurti
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail: (KS); (MAP)
| | - Sandra L. Siedlak
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - George Perry
- UTSA Neurosciences Institute and Department of Biology, College of Sciences, University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Mark A. Smith
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Miguel A. Pappolla
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail: (KS); (MAP)
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Bodó E, Kany B, Gáspár E, Knüver J, Kromminga A, Ramot Y, Bíró T, Tiede S, van Beek N, Poeggeler B, Meyer KC, Wenzel BE, Paus R. Thyroid-stimulating hormone, a novel, locally produced modulator of human epidermal functions, is regulated by thyrotropin-releasing hormone and thyroid hormones. Endocrinology 2010; 151:1633-42. [PMID: 20176727 DOI: 10.1210/en.2009-0306] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Several elements of the hypothalamic-pituitary-thyroid axis (HPT) reportedly are transcribed by human skin cell populations, and human hair follicles express functional receptors for TSH. Therefore, we asked whether the epidermis of normal human skin is yet another extrathyroidal target of TSH and whether epidermis even produces TSH. If so, we wanted to clarify whether intraepidermal TSH expression is regulated by TRH and/or thyroid hormones and whether TSH alters selected functions of normal human epidermis in situ. TSH and TSH receptor (TSH-R) expression were analyzed in the epidermis of normal human scalp skin by immunohistochemistry and PCR. In addition, full-thickness scalp skin was organ cultured and treated with TSH, TRH, or thyroid hormones, and the effect of TSH treatment on the expression of selected genes was measured by quantitative PCR and/or quantitative immunohistochemistry. Here we show that normal human epidermis expresses TSH at the mRNA and protein levels in situ and transcribes TSH-R. It also contains thyrostimulin transcripts. Intraepidermal TSH immunoreactivity is up-regulated by TRH and down-regulated by thyroid hormones. Although TSH-R immunoreactivity in situ could not be documented within the epidermis, but in the immediately adjacent dermis, TSH treatment of organ-cultured human skin strongly up-regulated epidermal expression of involucrin, loricrin, and keratins 5 and 14. Thus, normal human epidermis in situ is both an extrapituitary source and (possibly an indirect) target of TSH signaling, which regulates defined epidermal parameters. Intraepidermal TSH expression appears to be regulated by the classical endocrine controls that determine the systemic HPT axis.
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Affiliation(s)
- Eniko Bodó
- Department of Dermatology, University of Lübeck, Ratzeburger Allee 160, D-23538 Lübeck, Germany
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Langan E, Ramot Y, Hanning A, Poeggeler B, Bíró T, Gaspar E, Funk W, Griffiths C, Paus R. Thyrotropin-releasing hormone and oestrogen differentially regulate prolactin and prolactin receptor expression in female human skin and hair follicles in vitro. Br J Dermatol 2010; 162:1127-31. [DOI: 10.1111/j.1365-2133.2010.09676.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Pandi-Perumal SR, Trakht I, Srinivasan V, Spence DW, Poeggeler B, Hardeland R, Cardinali DP. The effect of melatonergic and non-melatonergic antidepressants on sleep: weighing the alternatives. World J Biol Psychiatry 2010; 10:342-54. [PMID: 18609422 DOI: 10.1080/15622970701625600] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In DSM-IV the occurrence of disturbed sleep is one of the principal diagnostic criteria for major depressive disorder (MDD). Further, there is evidence of reciprocity between the two conditions such that, even in the absence of current depressive symptoms, disturbed sleep often predicts their development. The present review discusses the effects of antidepressants on sleep and evaluates the use of the recently developed melatonin agonist-selective serotonin antagonists on sleep and depression. Although many antidepressants such as the tricyclics, monoamine oxidase inhibitors, serotonin-norepinephrine reuptake inhibitors, several serotonin receptor antagonists and selective serotonin reuptake inhibitors (SSRIs) have all been found successful in treating depression, their use is often associated with a disruptive effect on sleep. SSRIs, currently the most widely prescribed of the antidepressants, are well known for their instigation or exacerbation of insomnia. The recently introduced novel melatonin agonist and selective serotonin antagonist antidepressant, agomelatine, which has melatonin MT(1) and MT(2) receptor agonist and 5-HT(2c) antagonist properties, has been useful in treating patients with MDD. Its rapid onset of action and effectiveness in improving the mood of depressed patients has been attributed to its ability to improve sleep quality. These properties underline the use of melatonin analogues as a promising alternative for the treatment of depression.
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Affiliation(s)
- Seithikurippu R Pandi-Perumal
- Division of Clinical Pharmacology and Experimental Therapeutics, Department of Medicine, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
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Affiliation(s)
| | | | | | - Tamás Bíró
- Department of PhysiologyUniversity of DebrecenDebrecenHungary
- Abiol LtdDebrecenHungary
| | | | | | - Rudolf J. Wiesner
- Department of Vegetative PhysiologyUniversity of CologneCologneGermany
- Cologne Excellence Cluster: Cellular Stress Responses in Aging‐Associated Diseases (CECAD)CologneGermany
- Center for Molecular Medicine Cologne (CMMC)CologneGermany
| | | | - Ralf Paus
- Department of DermatologyGermany
- School of Translational MedicineUniversity of ManchesterManchesterUK
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Poeggeler B, Bodó E, Nadrowitz R, Dunst J, Paus R. A simple assay for the study of human hair follicle damage induced by ionizing irradiation. Exp Dermatol 2009; 19:e306-9. [DOI: 10.1111/j.1600-0625.2009.01009.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Farman N, Maubec E, Poeggeler B, Klatte JE, Jaisser F, Paus R. The mineralocorticoid receptor as a novel player in skin biology: beyond the renal horizon? Exp Dermatol 2009; 19:100-7. [PMID: 19925636 DOI: 10.1111/j.1600-0625.2009.01011.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The mineralocorticoid receptor (MR) and its ligand aldosterone regulate renal sodium reabsorption and blood pressure and much knowledge has been accumulated in MR physiopathology, cellular and molecular targets. In contrast, our understanding of this hormonal system in non-classical targets (heart, blood vessels, neurons, keratinocytes...) is limited, particularly in the mammalian skin. We review here the few available data that point on MR in the skin and that document cutaneous MR expression and function, based on mouse models and very limited observations in humans. Mice that overexpress the MR in the basal epidermal keratinocytes display developmental and post-natal abnormalities of the epidermis and hair follicle, raising exciting new questions regarding skin biology. The MR as a transcription factor may be an unexpected novel player in regulating keratinocyte and hair physiology and pathology. Because its activating ligand also includes glucocorticoids, that are widely used in dermatology, we propose that the MR may be also involved in the side-effects of corticoids, opening novel options for therapeutical intervention.
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Affiliation(s)
- Nicolette Farman
- INSERM U 872, Centre de Recherche des Cordeliers, Université Pierre et Marie Curie, Paris, France.
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Abstract
Here, we examine the currently available information which supports that the adipokine, leptin, is a major player in the biology and pathology of mammalian skin and its appendages. Specifically, the potent metabolic effects of leptin and its mimetics may be utilized to improve, preserve and restore skin regeneration and hair cycle progression, and may halt or even partially reverse some aspects of skin ageing. Since leptin can enhance mitochondrial activity and biogenesis, this may contribute to the wound healing-promoting and hair growth-modulatory effects of leptin. Leptin dependent intracellular signalling by the Janus kinase 2 dependent signal transducer and activator of transcription 3, adenosine monophosphate kinase, and peroxisome proliferator-activated receptor (PPAR) gamma coactivator/PPAR converges to mediate mitochondrial metabolic activation and enhanced cell proliferation which may orchestrate the potent developmental, trophic and protective effects of leptin. Since leptin and leptin mimetics have already been clinically tested, investigative dermatology is well-advised to place greater emphasis on the systematic exploration of the cutaneous dimensions and dermatological potential of this pleiotropic hormone.
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Srinivasan V, Pandi-Perumal SR, Trahkt I, Spence DW, Poeggeler B, Hardeland R, Cardinali DP. Melatonin and melatonergic drugs on sleep: possible mechanisms of action. Int J Neurosci 2009; 119:821-46. [PMID: 19326288 DOI: 10.1080/00207450802328607] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pineal melatonin is synthesized and secreted in close association with the light/dark cycle. The temporal relationship between the nocturnal rise in melatonin secretion and the "opening of the sleep gate" (i.e., the increase in sleep propensity at the beginning of the night), coupled with the sleep-promoting effects of exogenous melatonin, suggest that melatonin is involved in the regulation of sleep. The sleep-promoting and sleep/wake rhythm regulating effects of melatonin are attributed to its action on MT(1) and MT(2) melatonin receptors present in the suprachiasmatic nucleus (SCN) of the hypothalamus. Animal experiments carried out in rats, cats, and monkeys have revealed that melatonin has the ability to reduce sleep onset time and increase sleep duration. However, clinical studies reveal inconsistent findings, with some of them reporting beneficial effects of melatonin on sleep, whereas in others only marginal effects are documented. Recently a prolonged-release 2-mg melatonin preparation (Circadin(TM)) was approved by the European Medicines Agency as a monotherapy for the short-term treatment of primary insomnia in patients who are aged 55 or above. Several melatonin derivatives have been shown to increase nonrapid eye movement (NREM) in rats and are of potential pharmacological importance. So far only one of these melatonin derivatives, ramelteon, has received approval from the U.S. Food and Drug Administration to be used as a sleep promoter. Ramelteon is a novel MT(1) and MT(2) melatonergic agonist that has specific effects on melatonin receptors in the SCN and is effective in promoting sleep in experimental animals such as cats and monkeys. In clinical trials, ramelteon reduced sleep onset latency and promoted sleep in patients with chronic insomnia, including an older adult population. Both melatonin and ramelteon promote sleep by regulating the sleep/wake rhythm through their actions on melatonin receptors in the SCN, a unique mechanism of action not shared by any other hypnotics. Moreover, unlike benzodiazepines, ramelteon causes neither withdrawal effects nor dependence. Agomelatine, another novel melatonergic antidepressant in its final phase of approval for clinical use, has been shown to improve sleep in depressed patients and to have an antidepressant efficacy that is partially attributed to its effects on sleep-regulating mechanisms.
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Affiliation(s)
- Venkataramanujan Srinivasan
- SRM Medical College Hospital and Research Centre, SRM University, Kattankulathoor, Kancheepuram District, India
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Abstract
Melatonin (CAS 73-31-4) has both hypnotic and sleep/wake rhythm regulating properties. These sleep promoting actions, which are already demonstrable in healthy humans, have been found useful in subjects suffering from circadian rhythm sleep disorders (CRSD) like delayed sleep phase syndrome (DSPS), jet lag and shift-work sleep disorder. Low nocturnal melatonin production and secretion have been documented in elderly insomniacs, and exogenous melatonin has been shown to be beneficial in treating sleep disturbances of these patients. In comparison to a number of sleep-promoting compounds that are usually prescribed, such as benzodiazepines and z-drugs (zolpidem and zopiclon belonging to the latter ones), melatonin has several advantages of clinical value: it does not cause hangover nor withdrawal effects and is devoid of any addictive potential. However, recent meta-analyses revealed that melatonin is not sufficiently effective in treating most primary sleep disorders. Some of the reasons for a limited efficacy of this natural hormone are related to its extremely short half-life in the circulation, and to the fact that sleep maintenance is also regulated by mechanisms downstream of primary melatonergic actions. Hence, there is an urgent need for the development of melatonin receptor agonists with a longer half-life, which could be suitable for a successful treatment of insomnia. Such requirements are fulfilled by ramelteon (CAS 196597-26-9), which possesses a high affinity for the melatonin receptors MT1 and MT2 present in the circadian pacemaker, the suprachiasmatic nucleus (SCN). Ramelteon also has a substantially longer half-life than melatonin. This new drug has been successfully used in treating elderly insomniacs without any adverse effects reported, and is promising for treating patients with primary insomnia and also those suffering from CRSD. Since sleep disturbances constitute the most prevalent symptoms of various forms of depression, the need for the development of an ideal antidepressant was felt, which would both improve sleep and mitigate depressive symptoms. Since most of the currently used antidepressants, including the selective serotonin re-uptake inhibitors worsen the sleep disturbances of depressive patients, another novel melatonergic drug, agomelatine (CAS 138112-76-2), holds some promise because of its particular combination of actions: it has a high affinity for MT1 and MT2 receptors in the SCN, but it acts additionally as a 5-HT(2C) antagonist [5-hydroxytryptamine (serotonin) receptor 2C antagonist]. The latter property, which is decisive for the antidepressive action, would not favor but potentially antagonize sleep, but this is overcome during night by the melatonergic, sleep-promoting effect. This drug has been found beneficial in treating patients with major depressive and seasonal affective disorders. Unlike the other antidepressants, agomelatine improves both sleep and clinical symptoms of depressive illness and does not have any of the side effects on sleep seen with other compounds in use. This property seems to be of particular value because of the aggravating effects of disturbed sleep in the development of depressive symptoms. Based on these facts, agomelatine seems to be a drug of superior efficacy with a promising future in the treatment of depressive disorders. However, long-term safety studies are required for both ramelteon and agomelatine, with a consideration of the pharmacology of their metabolites, their effects on redox metabolism, and of eventual undesired melatonergic effects, e. g., on reproductive functions. According to current data, both compounds seem to be safe during short-term treatment
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Affiliation(s)
- Rüdiger Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, Universityof Göttingen, Göttingen, Germany.
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Behrends A, Riediger S, Grube S, Poeggeler B, Haldar C, Hardeland R. Photocatalytic mechanisms of indoleamine destruction by the quinalphos metabolite 2-hydroxyquinoxaline: a study on melatonin and its precursors serotonin and N-acetylserotonin. J Environ Sci Health B 2007; 42:599-606. [PMID: 17701694 DOI: 10.1080/03601230701465437] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The redox-active quinalphos main metabolite, 2-hydroxyquinoxaline, is particularly effective under excitation by light. We have studied the photocatalytic destruction of melatonin and its precursors, because the cytoprotective indoleamine has been detected in high quantities in mammalian skin. In photooxidation reactions, in which melatonin, N-acetylserotonin and serotonin are destroyed by 2-hydroxyquinoxaline, the photocatalyst is virtually not consumed. Rates of melatonin and serotonin destruction are not changed by the singlet oxygen quencher 1,4-diazabicyclo-(2,2,2)-octane, indicating that this oxygen species is not involved in the primary reactions, so that the persistence of 2-hydroxyquinoxaline has to be explained by redox cycling. This should imply formation of an organic radical, presumably the quinoxaline-2-oxyl radical, from which 2-hydroxyquinoxaline is regenerated by electron abstraction from indolic radical scavengers. Electron donation by 2-hydroxyquinoxaline is demonstrated by reduction of the 2,2'-azino-bis-(3-ethylbenzthiazolinyl-6-sulfonic acid) cation radical under ultrasound excitation. The compound 2-hydroxyquinoxaline interacts with the specific superoxide anion scavenger Tiron. Formation of oligomeric products from melatonin and serotonin is strongly inhibited by sodium dithionite. Products from photocatalytic indolamine conversion are predominantly dimers and oligomers. No kynuramines were detected in the case of serotonin oxidation, and melatonin's otherwise prevailing oxidation product N(1)-acetyl-N(2)-formyl-5-methoxykynuramine, another cytoprotective metabolite, is only formed in relatively small quantities. The proportion between products from melatonin is changed by 1,4-diazabicyclo-(2,2,2)-octane: singlet oxygen, also formed under the influence of excited 2-hydroxyquinoxaline, only affects secondary reactions.
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Affiliation(s)
- Andreas Behrends
- Institute of Zoology and Anthropology, University of Goettingen, Goettingen, Germany
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Durand G, Poeggeler B, Böker J, Raynal S, Polidori A, Pappolla MA, Hardeland R, Pucci B. Fine-tuning the amphiphilicity: a crucial parameter in the design of potent alpha-phenyl-N-tert-butylnitrone analogues. J Med Chem 2007; 50:3976-9. [PMID: 17649989 DOI: 10.1021/jm0706968] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new series of hydrophilic, lipophilic, and amphiphilic alpha-phenyl-N-tert-butylnitrone (PBN) derivatives were synthesized to explore the relationship between their hydrophilic-lipophilic properties and antioxidant potency. Very potent protective effects of amphiphilic lactobionamide and tris(hydroxymethyl)aminomethane PBN derivatives were observed in mitochondrial preparations, in cell cultures, and in rotifers exposed to unspecific and mitochondria targeted oxidotoxins.
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Affiliation(s)
- Grégory Durand
- Laboratoire de Chimie BioOrganique et des Systèmes Moléculaires Vectoriels, Faculté des Sciences, Université d'Avignon et des Pays de Vaucluse, 33 Rue Louis Pasteur, 84000 Avignon, France
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Poeggeler B, Rassoulpour A, Wu HQ, Guidetti P, Roberts RC, Schwarcz R. Dopamine receptor activation reveals a novel, kynurenate-sensitive component of striatal N-methyl-D-aspartate neurotoxicity. Neuroscience 2007; 148:188-97. [PMID: 17629627 PMCID: PMC2034343 DOI: 10.1016/j.neuroscience.2007.05.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Revised: 05/04/2007] [Accepted: 05/07/2007] [Indexed: 11/24/2022]
Abstract
The N-methyl-d-aspartate (NMDA) subtype of glutamate receptors plays an important role in brain physiology, but excessive receptor stimulation results in seizures and excitotoxic nerve cell death. NMDA receptor-mediated neuronal excitation and injury can be prevented by high, non-physiological concentrations of the neuroinhibitory tryptophan metabolite kynurenic acid (KYNA). Here we report that endogenous KYNA, which is formed in and released from astrocytes, controls NMDA receptors in vivo. This was revealed with the aid of the dopaminergic drugs d-amphetamine and apomorphine, which cause rapid, transient decreases in striatal KYNA levels in rats. Intrastriatal injections of the excitotoxins NMDA or quinolinate (but not the non-NMDA receptor agonist kainate) at the time of maximal KYNA reduction resulted in two- to threefold increases in excitotoxic lesion size. Pre-treatment with a kynurenine 3-hydroxylase inhibitor or with dopamine receptor antagonists, i.e., two classes of pharmacological agents that prevented the reduction in brain KYNA caused by dopaminergic stimulation, abolished the potentiation of neurotoxicity. Thus, the present study identifies a previously unappreciated role of KYNA as a functional link between dopamine receptor stimulation and NMDA neurotoxicity in the striatum.
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Affiliation(s)
- B Poeggeler
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, P.O. Box 21247, Baltimore, MD 21228, USA
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Pandi-Perumal SR, Srinivasan V, Poeggeler B, Hardeland R, Cardinali DP. Drug Insight: the use of melatonergic agonists for the treatment of insomnia-focus on ramelteon. ACTA ACUST UNITED AC 2007; 3:221-8. [PMID: 17410109 DOI: 10.1038/ncpneuro0467] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Accepted: 01/30/2007] [Indexed: 12/27/2022]
Abstract
Melatonin, a chronobiotic that participates in the control of the circadian system, is known for its sleep-promoting effects, which include shortening of sleep latency and lengthening of sleep duration. As a result of its short half-life, melatonin does not exhibit undesirable side effects, and its broad applicability for a variety of sleep problems has been the focus of numerous scientific studies. Melatonin has not, however, received regulatory approval from the US FDA as a drug, because it can be sold freely as a food supplement. Consequently, there has been an active search for patentable melatonin receptor ligands in recent years. Ramelteon, an agonist that acts solely on melatonin MT(1) and MT(2) receptors, is of particular interest, and preliminary research indicates that it holds considerable promise for clinical applications. Ramelteon has been shown to induce sleep initiation and maintenance in various animal models and in clinical trials. In chronic insomnia, ramelteon decreases sleep latency and increases total sleep time and sleep efficiency, without causing hangover, addiction or withdrawal effects. Ramelteon is thought to promote sleep by influencing homeostatic sleep signaling mediated by the suprachiasmatic nucleus. Although ramelteon's metabolism and pharmacokinetics differ from those of melatonin, its safety seems to be sufficient for short-term application. Its long-term effects remain to be determined.
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Affiliation(s)
- Seithikurippu R Pandi-Perumal
- Comprehensive Center for Sleep Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA.
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Riediger S, Behrends A, Croll B, Vega-Naredo I, Hänig N, Poeggeler B, Böker J, Grube S, Gipp J, Coto-Montes A, Haldar C, Hardeland R. Toxicity of the quinalphos metabolite 2-hydroxyquinoxaline: growth inhibition, induction of oxidative stress, and genotoxicity in test organisms. Environ Toxicol 2007; 22:33-43. [PMID: 17295279 DOI: 10.1002/tox.20231] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The quinalphos metabolite 2-hydroxyquinoxaline (HQO), previously shown to photocatalytically destroy antioxidant vitamins and biogenic amines in vitro, was tested for toxicity in several small aquatic organisms and for mutagenicity in Salmonella typhimurium. In the rotifer Philodina acuticornis, HQO caused the disappearance of large individuals and increased hydroperoxide concentration. The latter effect was not only observed in animals kept in a light/dark cycle, but also in constant darkness, indicating that HQO can assume a reactive state and/or form reactive intermediates under the influence of either light or redox-active metabolites, in particular, free radicals. Cell proliferation was inhibited in the ciliate Paramecium bursaria. In the dinoflagellate Lingulodinium polyedrum, which allows early detection of cellular stress on the basis of bioluminescence measurements, strong rises in light emission became apparent on the 2nd day of exposure to HQO and continued until cells died between 12 and 18 days of treatment. Oxidative damage of protein by HQO was demonstrated by measuring protein carbonyl in L. polyedrumin vivo as well as in light-exposed bovine serum albumin in vitro. In an Ames test of mutagenicity, HQO proved to be genotoxic in both light- and dark-exposed bacteria. HQO appears as a source of secondary quinalphos toxicity, which deserves further attention.
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Affiliation(s)
- Sonja Riediger
- Institute of Zoology and Anthropology, University of Goettingen, Berliner Str. 28, D-37073 Goettingen, Germany
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Rosen J, Than NN, Koch D, Poeggeler B, Laatsch H, Hardeland R. Interactions of melatonin and its metabolites with the ABTS cation radical: extension of the radical scavenger cascade and formation of a novel class of oxidation products, C2-substituted 3-indolinones. J Pineal Res 2006; 41:374-81. [PMID: 17014695 DOI: 10.1111/j.1600-079x.2006.00379.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Melatonin had previously been shown to reduce up to four 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) cation radicals (ABTS*+) via a scavenger cascade ending with N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK). However, when melatonin is added to the reaction system in much lower quantities than ABTS*+, the number of radicals scavenged per melatonin molecule is considerably higher and can attain a value of ten. Under conditions allowing for such a stoichiometry, novel products have been detected which derive from AFMK (1). These were separated by repeated chromatography and the major compounds were characterized by spectroscopic methods, such as mass spectrometry (HPLC-MS, EI-MS and ESI-HRMS), 1H nuclear magnetic resonance (NMR) and 13C NMR, heteronuclear multiple bond connectivity (HMBC) correlations. The identified substances are formed by re-cyclization and represent 3-indolinones carrying the side chain at C2; the N-formyl group can be maintained, but deformylated analogs seem to be also generated, according to MS. The primary product from AFMK (1) is N-(1-formyl-5-methoxy-3-oxo-2,3-dihydro-1H-indol-2-ylidenemethyl)-acetamide (2), which is obtained after purification as E- and Z-isomers (2a, 2b); a secondary product has been identified as N-(1-formyl-2-hydroxy-5-methoxy-3-oxo-2,3-dihydro-1H-indol-2-ylmethyl)-acetamide (3). When H2O2 is added to the ABTS*+ reaction mixture in quantities not already leading to substantial reduction of this radical, compound 3 is isolated as the major product, whereas 2a and 2b are virtually absent. The substances formed differ from all previously known oxidation products which derive from melatonin and are, among these, the first 3-indolinones. Moreover, the aliphatic side chain at C2 is reminiscent of other substances which have been synthesized in the search for melatonin receptor ligands.
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Affiliation(s)
- Joachim Rosen
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, Göttingen, Germany
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Weishaupt JH, Bartels C, Pölking E, Dietrich J, Rohde G, Poeggeler B, Mertens N, Sperling S, Bohn M, Hüther G, Schneider A, Bach A, Sirén AL, Hardeland R, Bähr M, Nave KA, Ehrenreich H. Reduced oxidative damage in ALS by high-dose enteral melatonin treatment. J Pineal Res 2006; 41:313-23. [PMID: 17014688 DOI: 10.1111/j.1600-079x.2006.00377.x] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is the collective term for a fatal motoneuron disease of different etiologies, with oxidative stress as a common molecular denominator of disease progression. Melatonin is an amphiphilic molecule with a unique spectrum of antioxidative effects not conveyed by classical antioxidants. In preparation of a possible future clinical trial, we explored the potential of melatonin as neuroprotective compound and antioxidant in: (1) cultured motoneuronal cells (NSC-34), (2) a genetic mouse model of ALS (SOD1(G93A)-transgenic mice), and (3) a group of 31 patients with sporadic ALS. We found that melatonin attenuates glutamate-induced cell death of cultured motoneurons. In SOD1(G93A)-transgenic mice, high-dose oral melatonin delayed disease progression and extended survival. In a clinical safety study, chronic high-dose (300 mg/day) rectal melatonin was well tolerated during an observation period of up to 2 yr. Importantly, circulating serum protein carbonyls, which provide a surrogate marker for oxidative stress, were elevated in ALS patients, but were normalized to control values by melatonin treatment. This combination of preclinical effectiveness and proven safety in humans suggests that high-dose melatonin is suitable for clinical trials aimed at neuroprotection through antioxidation in ALS.
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Abstract
Melatonin is a ubiquitous molecule and widely distributed in nature, with functional activity occurring in unicellular organisms, plants, fungi and animals. In most vertebrates, including humans, melatonin is synthesized primarily in the pineal gland and is regulated by the environmental light/dark cycle via the suprachiasmatic nucleus. Pinealocytes function as 'neuroendocrine transducers' to secrete melatonin during the dark phase of the light/dark cycle and, consequently, melatonin is often called the 'hormone of darkness'. Melatonin is principally secreted at night and is centrally involved in sleep regulation, as well as in a number of other cyclical bodily activities. Melatonin is exclusively involved in signaling the 'time of day' and 'time of year' (hence considered to help both clock and calendar functions) to all tissues and is thus considered to be the body's chronological pacemaker or 'Zeitgeber'. Synthesis of melatonin also occurs in other areas of the body, including the retina, the gastrointestinal tract, skin, bone marrow and in lymphocytes, from which it may influence other physiological functions through paracrine signaling. Melatonin has also been extracted from the seeds and leaves of a number of plants and its concentration in some of this material is several orders of magnitude higher than its night-time plasma value in humans. Melatonin participates in diverse physiological functions. In addition to its timekeeping functions, melatonin is an effective antioxidant which scavenges free radicals and up-regulates several antioxidant enzymes. It also has a strong antiapoptotic signaling function, an effect which it exerts even during ischemia. Melatonin's cytoprotective properties have practical implications in the treatment of neurodegenerative diseases. Melatonin also has immune-enhancing and oncostatic properties. Its 'chronobiotic' properties have been shown to have value in treating various circadian rhythm sleep disorders, such as jet lag or shift-work sleep disorder. Melatonin acting as an 'internal sleep facilitator' promotes sleep, and melatonin's sleep-facilitating properties have been found to be useful for treating insomnia symptoms in elderly and depressive patients. A recently introduced melatonin analog, agomelatine, is also efficient for the treatment of major depressive disorder and bipolar affective disorder. Melatonin's role as a 'photoperiodic molecule' in seasonal reproduction has been established in photoperiodic species, although its regulatory influence in humans remains under investigation. Taken together, this evidence implicates melatonin in a broad range of effects with a significant regulatory influence over many of the body's physiological functions.
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Affiliation(s)
- S R Pandi-Perumal
- Comprehensive Center for Sleep Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA.
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Srinivasan V, Pandi-Perumal SR, Cardinali DP, Poeggeler B, Hardeland R. Melatonin in Alzheimer's disease and other neurodegenerative disorders. Behav Brain Funct 2006; 2:15. [PMID: 16674804 PMCID: PMC1483829 DOI: 10.1186/1744-9081-2-15] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Accepted: 05/04/2006] [Indexed: 12/15/2022] Open
Abstract
Increased oxidative stress and mitochondrial dysfunction have been identified as common pathophysiological phenomena associated with neurodegenerative disorders such as Alzheimer's disease (AD), Parkinson's disease (PD) and Huntington's disease (HD). As the age-related decline in the production of melatonin may contribute to increased levels of oxidative stress in the elderly, the role of this neuroprotective agent is attracting increasing attention. Melatonin has multiple actions as a regulator of antioxidant and prooxidant enzymes, radical scavenger and antagonist of mitochondrial radical formation. The ability of melatonin and its kynuramine metabolites to interact directly with the electron transport chain by increasing the electron flow and reducing electron leakage are unique features by which melatonin is able to increase the survival of neurons under enhanced oxidative stress. Moreover, antifibrillogenic actions have been demonstrated in vitro, also in the presence of profibrillogenic apoE4 or apoE3, and in vivo, in a transgenic mouse model. Amyloid-β toxicity is antagonized by melatonin and one of its kynuramine metabolites. Cytoskeletal disorganization and protein hyperphosphorylation, as induced in several cell-line models, have been attenuated by melatonin, effects comprising stress kinase downregulation and extending to neurotrophin expression. Various experimental models of AD, PD and HD indicate the usefulness of melatonin in antagonizing disease progression and/or mitigating some of the symptoms. Melatonin secretion has been found to be altered in AD and PD. Attempts to compensate for age- and disease-dependent melatonin deficiency have shown that administration of this compound can improve sleep efficiency in AD and PD and, to some extent, cognitive function in AD patients. Exogenous melatonin has also been reported to alleviate behavioral symptoms such as sundowning. Taken together, these findings suggest that melatonin, its analogues and kynuric metabolites may have potential value in prevention and treatment of AD and other neurodegenerative disorders.
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Affiliation(s)
- V Srinivasan
- Department of Physiology, School of Medical Sciences, University Sains Malaysia, Kampus Kesihatan, 16150, Kubang kerian, Kelantan, Malaysia
| | - SR Pandi-Perumal
- Comprehensive Center for Sleep Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Mount Sinai School of Medicine, 1176 – 5Avenue, New York, NY 10029, USA
| | - DP Cardinali
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, 1121, Buenos Aires, Argentina
| | - B Poeggeler
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Goettingen, Berliner Str. 28, D-37073 Goettingen, Germany
| | - R Hardeland
- Johann Friedrich Blumenbach Institute of Zoology and Anthropology, University of Goettingen, Berliner Str. 28, D-37073 Goettingen, Germany
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Ortial S, Durand G, Poeggeler B, Polidori A, Pappolla MA, Böker J, Hardeland R, Pucci B. Fluorinated Amphiphilic Amino Acid Derivatives as Antioxidant Carriers: A New Class of Protective Agents. J Med Chem 2006; 49:2812-20. [PMID: 16640342 DOI: 10.1021/jm060027e] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The use of classical antioxidants is limited by their low bioavailabilities, and therefore, high doses are usually required to display significant protective activity. In a recent article (J. Med. Chem. 2003, 46, 5230) we showed that the ability of the alpha-phenyl-N-tert-butylnitrone (PBN) to restore the viability of ATPase-deficient human skin fibroblasts was greatly enhanced by grafting it on a fluorinated amphiphilic carrier. With the aim of extending this concept to other antioxidants, we present here the design, the synthesis, and the physicochemical measurements of a new series of fluorinated amphiphilic antioxidant derivatives. The hydroxyl radical scavenging activity and the radical reducing potency of these newly designed compounds were respectively demonstrated in an ABTS competition and an ABTS(*+) reduction assay. We also showed that the protective effects of amphiphilic antioxidants derived from PBN, Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) or lipoic acid (5-[1,2]-dithiolan-3-ylpentanoic acid) in primary cortical mixed cell cultures exposed to oxidotoxins are greatly improved compared to their parent compounds in the following rank-order: (1) PBN, (2) Trolox, and (3) lipoic acid. In contrast, the protective activity of indole-3-propionic acid was slightly decreased by grafting it on the amphiphilic carrier. Similar observations were made in in vivo experiments using aquatic invertebrate microorganisms, called rotifers, which were exposed to lethal concentrations of nonselective (H(2)O(2)) and mitochondria-selective (doxorubicin) oxidotoxins. The conclusion of these studies is that fluorinated amphiphilic PBN, Trolox, and lipoic acid derivatives exhibit very potent protective activities in in vitro and in vivo experiments. The findings demonstrated herein therefore strongly suggest that the amphiphilic character enhances the bioavailability of the antioxidants and allows for a selective targeting of mitochondria.
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Affiliation(s)
- Stéphanie Ortial
- Laboratoire de Chimie BioOrganique et des Systèmes Moléculaires Vectoriels, Faculté des Sciences, Université d'Avignon et des Pays de Vaucluse, 84000 Avignon, France
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Guenther AL, Schmidt SI, Laatsch H, Fotso S, Ness H, Ressmeyer AR, Poeggeler B, Hardeland R. Reactions of the melatonin metabolite AMK (N1-acetyl-5-methoxykynuramine) with reactive nitrogen species: formation of novel compounds, 3-acetamidomethyl-6-methoxycinnolinone and 3-nitro-AMK. J Pineal Res 2005; 39:251-60. [PMID: 16150105 DOI: 10.1111/j.1600-079x.2005.00242.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The melatonin metabolite N1-acetyl-5-methoxykynuramine (AMK) was found to be unstable in air when adsorbed on a thin-layer silica gel chromatography plate, a result that is in good agreement with the relatively high reactivity of this compound. Three novel main products were separated from the reaction mixture and identified by mass spectrometry and nuclear magnetic resonance data as: (i) 3-acetamidomethyl-6-methoxycinnolinone (AMMC), (ii) 3-nitro-AMK (AMNK, N1-acetyl-5-methoxy-3-nitrokynuramine), and (iii) N-[2-(6-methoxyquinazolin-4-yl)-ethyl]-acetamide (MQA). AMMC and AMNK are shown to be nonenzymatically formed also in solution, by nitric oxide (NO) in the first case, and by a mixture of peroxynitrite and hydrogen carbonate, in the second one. The use of three different NO donors, PAPA-NONOate, S-nitroso-N-acetylpenicillamine and sodium nitroprussiate led to essentially the same results, with regard to a highly preferential formation of AMMC; AMNK was not detected in these reaction systems. Competition experiments with the NO scavenger N-acetylcysteine indicate a somewhat lower reactivity compared with the competitor. Peroxynitrite led to AMNK formation in the presence of physiological concentrations of hydrogen carbonate at pH 7.4, but not in its absence, indicating that nitration involves a mixture of carbonate radicals and NO2, formed from the peroxynitrite-CO2 adduct. No AMMC was detected after AMK exposure to peroxynitrite. Both AMNK and AMMC exhibited a much lower reactivity toward 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) cation radicals than did AMK. In a competition assay for hydroxyl radicals, AMMC showed prooxidant properties, whereas AMNK was a moderate antioxidant. AMMC and AMNK should represent relatively stable physiological products, although their rates of synthesis are still unknown and may be low. Formation of these compounds may contribute to the disappearance of AMK from tissues and body fluids.
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Affiliation(s)
- Anna L Guenther
- Institute of Zoology, Anthropology and Developmental Biology, University of Göttingen, Göttingen, Germany
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Stebelova K, Zeman M, Cornélissen G, Bubenik G, Jozsa R, Hardeland R, Poeggeler B, Huether G, Olah A, Nagy G, Csernus V, Kazsaki J, Pan W, Otsuka K, Bakken EE, Halberg F. Chronomics reveal and quantify circadian rhythmic melatonin in duodenum of rats. Biomed Pharmacother 2005; 59 Suppl 1:S209-12. [PMID: 16275496 PMCID: PMC2577083 DOI: 10.1016/s0753-3322(05)80033-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
A circadian rhythm is documented in duodenal melatonin in rats, peaking 16.8 hours after light onset. This component is more readily detected after log10-transformation of the data. It differs between male and female rats, females having a larger circadian amplitude and an earlier acrophase. The circadian rhythm in duodenal melatonin is also found to lead that of pineal melatonin. The results are qualified by the presence at the start of mapping of the second extremum of a double magnetic storm.
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Vega-Naredo I, Poeggeler B, Sierra-Sánchez V, Caballero B, Tomás-Zapico C, Alvarez-García O, Tolivia D, Rodríguez-Colunga MJ, Coto-Montes A. Melatonin neutralizes neurotoxicity induced by quinolinic acid in brain tissue culture. J Pineal Res 2005; 39:266-75. [PMID: 16150107 DOI: 10.1111/j.1600-079x.2005.00243.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Quinolinic acid is a well-known excitotoxin that induces oxidative stress and damage. In the present study, oxidative damage to biomolecules was followed by measuring lipid peroxidation and protein carbonyl formation in rat brain tissue culture over a period of 24 hr of exposure to this prooxidant agent at a concentration of 0.5 mm. Quinolinic acid enhanced lipid peroxidation in an early stage of tissue culture, and protein carbonyl at a later stage. These data confirm and extend previous studies demonstrating that quinolinic acid can induce significant oxidative damage. Melatonin, an antioxidant and neuroprotective agent with multiple actions as a radical scavenger and signaling molecule, completely prevented these prooxidant actions of quinolinic acid at a concentration of 1 mm. Morphological lesions and neurotoxicity induced by quinolinic acid were evaluated by light microscopy. Quinolinic acid produced extensive apoptosis/necrosis which was significantly attenuated by melatonin. Cotreatment with melatonin exerted a profound protective effect antagonizing the neurotoxicity induced by quinolinic acid. Glutathione reductase and catalase activities were increased by quinolinic acid and these effects were antagonized by melatonin. Furthermore, melatonin induced superoxide dismutase activity. Quinolinic acid and melatonin acted independently and by different mechanisms in modulating antioxidant enzyme activities. Our findings using quinolinic acid and melatonin clearly demonstrate that such changes should always be seen in the context of oxidative neurotoxicity and antioxidant neuroprotection.
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Affiliation(s)
- Ignacio Vega-Naredo
- Departamento de Morfología y Biología Celular, Facultad de Medicina, Universidad de Oviedo, Oviedo, Asturias, Spain
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Zeman M, Józsa R, Cornélissen G, Stebelova K, Bubenik G, Olah A, Poeggeler B, Huether G, Hardeland R, Nagy G, Czernus V, Pan W, Otsuka K, Halberg F. Chronomics: circadian lead of extrapineal vs. pineal melatonin rhythms with an infradian hypothalamic exploration. Biomed Pharmacother 2005; 59 Suppl 1:S213-9. [PMID: 16275497 DOI: 10.1016/s0753-3322(05)80034-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
A circadian rhythm is documented for plasma, pineal, and hypothalamic melatonin of male and female rats kept on staggered lighting regimens. Log[_10]-transformation of the data usually normalizes, when need be, the distribution of residuals from the 24-hour cosine curve fits. A tentative circadian acrophase chart is presented that shows a lead in circadian acrophase of duodenal over pineal melatonin. The use of antiphasic lighting regimens facilitates circadian studies that can be carried out for several days, thereby allowing the assessment of infradian components such as a circasemiseptan variation in hypothalamic melatonin documented herein. The results are qualified by the presence of a second extremum of a double magnetic storm at the start of mapping.
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Affiliation(s)
- M Zeman
- Comenius University, Bratislava, Slovakia
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Halberg F, Cornélissen G, Faraone P, Poeggeler B, Hardeland R, Katinas G, Schwartzkopff O, Otsuka K, Bakken EE. Prokaryotic and eukaryotic unicellular chronomics. Biomed Pharmacother 2005; 59 Suppl 1:S192-202. [PMID: 16275493 PMCID: PMC3082478 DOI: 10.1016/s0753-3322(05)80031-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
An impeccable time series, published in 1930, consisting of hourly observations on colony advance in a fluid culture of E. coli, was analyzed by a periodogram and power spectrum in 1961. While the original senior author had emphasized specifically periodicity with no estimate of period length, he welcomed further analyses. After consulting his technician, he knew of no environmental periodicity related to human schedules other than an hourly photography. A periodogram analysis in 1961 showed a 20.75-h period. It was emphasized that "... the circadian period disclosed is not of exactly 24-h length." Confirmations notwithstanding, a committee ruled out microbial circadian rhythms based on grounds that could have led to a different conclusion, namely first, the inability of some committee members to see (presumably by eyeballing) the rhythms in their own data, and second, what hardly follows, that there were "too many analyses" in the published papers. Our point in dealing with microbes and humans is that analyses are indispensable for quantification and for discovering a biologically novel spectrum of cyclicities, matching physical ones. The scope of circadian organization estimated in 1961 has become broader, including about 7-day, about half-yearly, about-yearly and ex-yearly and decadal periodisms, among others. Microbial circadians have become a field of their own with eyeballing, yet time-microscopy can quantify characteristics with their uncertainties and can assess broad chronomes (time structures) with features beyond circadians. As yet only suggestive differences between eukaryotes and prokaryotes further broaden the perspective and may lead to life's sites of origin and to new temporal aspects of life's development as a chronomic tree by eventual rhythm dating in ontogeny and phylogeny.
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Affiliation(s)
- F. Halberg
- Halberg Chronobiology Center, University of Minnesota, Mayo Mail Code 8609, 420 Delaware Street SE, Minneapolis, MN 55455, USA
- Corresponding authors. E-mail address: corne001 @umn.edu(G. Cornélissen); (F. Halberg). Website: http://www.msi.umn.edu/~halberg
| | - G. Cornélissen
- Halberg Chronobiology Center, University of Minnesota, Mayo Mail Code 8609, 420 Delaware Street SE, Minneapolis, MN 55455, USA
- Corresponding authors. E-mail address: corne001 @umn.edu(G. Cornélissen); (F. Halberg). Website: http://www.msi.umn.edu/~halberg
| | | | | | | | - G. Katinas
- Halberg Chronobiology Center, University of Minnesota, Mayo Mail Code 8609, 420 Delaware Street SE, Minneapolis, MN 55455, USA
| | - O. Schwartzkopff
- Halberg Chronobiology Center, University of Minnesota, Mayo Mail Code 8609, 420 Delaware Street SE, Minneapolis, MN 55455, USA
| | - K. Otsuka
- Tokyo Women’s Medical University, Tokyo, Japan
| | - E. E. Bakken
- North Hawaii Community Hospital, Kamuela, HI, USA
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Poeggeler B, Cornélissen G, Huether G, Hardeland R, Józsa R, Zeman M, Stebelova K, Oláh A, Bubenik G, Pan W, Otsuka K, Schwartzkopff O, Bakken EE, Halberg F. Chronomics affirm extending scope of lead in phase of duodenal vs. pineal circadian melatonin rhythms. Biomed Pharmacother 2005; 59 Suppl 1:S220-4. [PMID: 16275498 PMCID: PMC2662383 DOI: 10.1016/s0753-3322(05)80035-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In Göttingen, Germany, circadian variations in melatonin had been determined time-macroscopically in pineal glands, blood plasma and duodenum of chicken and rats. When these data were meta-analyzed, they agreed with the results from an independent survey on tissues from rats collected in a laboratory in Pécs, Hungary. In the latter study, tissues were analyzed chemically in Bratislava, Slovakia, and numerically in Minneapolis, MN, USA, all by single- and multiple-component cosinor and parameter tests. In rats and chickens, these inferential statistical procedures clearly demonstrated a lead in phase of the 24-h cosine curves best fitting all of the duodenal vs. those best fitting all of the pineal melatonin values in each species in 2 geographic (geomagnetic) locations. The 24-h cosine curve of circulating melatonin was found to be in an intermediate phase position. Mechanisms of the phase differences and the contribution of gastrointestinal melatonin to circulating hormone concentrations are discussed.
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Affiliation(s)
- B Poeggeler
- Institute of Zoology, Anthropology and Developmental Biology, University of Göttingen, Göttingen, Germany
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Tan DX, Manchester LC, Sainz RM, Mayo JC, Leon J, Hardeland R, Poeggeler B, Reiter RJ. Interactions between melatonin and nicotinamide nucleotide: NADH preservation in cells and in cell-free systems by melatonin. J Pineal Res 2005; 39:185-94. [PMID: 16098097 DOI: 10.1111/j.1600-079x.2005.00234.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Interactions of melatonin and nicotinamide adenine dinucleotide (NADH) have been studied in different experimental models including NADH-promoted oxyhemoglobin oxidation, vanadate-induced NADH oxidation and paraquat-induced NADH depletion in cultured PC12 cells. Our findings indicate that melatonin preserves NADH levels under oxidative stress both in cell-free systems and in cultured PC12 cells. These interactions likely involve electron donation by melatonin and reduction of the NAD radical. As a result, the NAD radical is recycled to NADH and melatonin is oxidized to N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK). NADH is a central molecule at the crossroads between energy metabolism and the antioxidant defense system in organisms. Recycling of NADH by melatonin might improve the efficiency of NADH as an energy carrier and as an antioxidant. Interactions between melatonin and NADH may be implicated in mitochondrial metabolism.
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Affiliation(s)
- Dun-Xian Tan
- Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
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Poeggeler B, Durand G, Polidori A, Pappolla MA, Vega-Naredo I, Coto-Montes A, Böker J, Hardeland R, Pucci B. Mitochondrial medicine: neuroprotection and life extension by the new amphiphilic nitrone LPBNAH acting as a highly potent antioxidant agent. J Neurochem 2005; 95:962-73. [PMID: 16135084 DOI: 10.1111/j.1471-4159.2005.03425.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The search for effective treatments that prevent oxidative stress associated with premature ageing and neurodegenerative diseases is an important area of neurochemical research. As age- and disease-related oxidative stress is frequently associated with mitochondrial dysfunction, amphiphilic antioxidant agents of high stability and selectivity that target these organelles can provide on-site protection. Such an amphiphilic nitrone protected human neuroblastoma cells at low micromolar concentrations against oxidative damage and death induced by exposure to the beta-amyloid peptide, hydrogen peroxide and 3-hydroxykynurenine. Daily administration of the antioxidant at a concentration of only 5 mum significantly increased the lifespan of the individually cultured rotifer Philodina acuticornis odiosa Milne. This compound is unique in its exceptional anti-ageing efficacy, being one order of magnitude more potent than any other compound previously tested on rotifers. The nitrone protected these aquatic animals against the lethal toxicity of hydrogen peroxide and doxorubicin and greatly enhanced their survival when co-administered with these oxidotoxins. These findings indicate that amphiphilic antioxidants have a great potential as neuroprotective agents in preventing the death of cells and organisms exposed to enhanced oxidative stress and damage.
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Affiliation(s)
- Burkhard Poeggeler
- Abteilung fuer Stoffwechselphysiologie, Institut fuer Zoologie, Anthropologie und Entwicklungsbiologie der Georg August Universitaet Goettingen, Goettingen, Germany.
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Abstract
The high incidence of age-related diseases in the increasing population of elderly people has stimulated interest in the search for protective agents that have the capability of preventing premature aging and delaying the onset of degenerative disorders. To preserve health in old age becomes a primary goal for biomedicine, because the increasing longevity in our societies is associated with a rise in morbidity. The difficulties in finding new approaches and safe strategies for prevention, intervention, and treatment are related to the lack of theoretical background as well as to insufficient models to test the efficacy of anti-aging agents. Melatonin is a prime candidate for slowing the aging process and targeting its underlying pathology. Melatonin has profound gerontoprotective and antioxidant activities. Because enhanced oxidative stress plays a crucial role in the aging process and chronic diseases associated with senescence, the adminstration of a potent amphiphilic antioxidant agent with high bioavailability such as melatonin may become a promising, safe, and effective intervention strategy to slow aging and the initiation and progression of age-related disorders. Investigations on melatonin and its anti-aging activity may be of great benefit in increasing life quality of the elderly.
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Affiliation(s)
- Burkhard Poeggeler
- Institute of Zoology, Anthropology and Developmental Biology, University of Goettingen, Goettingen, Germany.
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