1
|
Rahangdale S, Fating R, Gajbhiye M, Kapse M, Inamdar N, Kotagale N, Umekar M, Taksande B. Involvement of agmatine in antidepressant-like effect of HMG-CoA reductase inhibitors in mice. Eur J Pharmacol 2020; 892:173739. [PMID: 33220274 DOI: 10.1016/j.ejphar.2020.173739] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/28/2020] [Accepted: 11/04/2020] [Indexed: 02/06/2023]
Abstract
3-Hydroxy-3-methyl-glutaryl-co-enzyme-A (HMG-CoA) reductase inhibitors (statins) are popularly used for the treatment of obesity and hypercholesterolemia with established safety profile. Statins exhibits a wide range of neurobehavioral effects in addition to their peripheral actions, and may be beneficial in treatment of psychiatric conditions. Present study investigated the role of agmatine and imidazoline receptors in antidepressant-like effect of statins in mouse forced swimming test (FST). The antidepressant-like effect of atorvastatin (5 mg/kg, p.o.) and simvastatin (10 mg/kg, p.o.) was potentiated by pretreatment with agmatine (5 mg/kg, i.p.) as well as the drugs known to increase endogenous agmatine levels in brain viz., L-arginine (40 μg/mouse, i.c.v.), an agmatine biosynthetic precursor; arcaine (50 μg/mouse, i.c.v), agmatinase inhibitor; and aminoguanidine (6.5 μg/mouse, i.c.v.), a diamine oxidase inhibitor. Further, both the statins increased agmatine levels within hippocampus and prefrontal cortex. Conversely, prior administration of I1 receptor antagonist, efaroxan (1 mg/kg, i.p.) and I2 receptor antagonist, idazoxan (0.25 mg/kg, i.p.) blocked the antidepressant-like effect of statins and their synergistic combination with agmatine. These results demonstrate the involvement of agmatine and imidazoline receptors in antidepressant-like effect of statins and suggest as a potential therapeutic target for the treatment of depressive disorders.
Collapse
Affiliation(s)
- Sandip Rahangdale
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India
| | - Rajshree Fating
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India
| | - Mona Gajbhiye
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India
| | - Mona Kapse
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India
| | - Nazma Inamdar
- Government College of Pharmacy, Kathora Naka, VMV Road, Amravati, M.S, 444604, India
| | - Nandkishor Kotagale
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India; Government College of Pharmacy, Kathora Naka, VMV Road, Amravati, M.S, 444604, India
| | - Milind Umekar
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India
| | - Brijesh Taksande
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, M.S, 441 002, India.
| |
Collapse
|
2
|
Kotagale N, Deshmukh R, Dixit M, Fating R, Umekar M, Taksande B. Agmatine ameliorates manifestation of depression-like behavior and hippocampal neuroinflammation in mouse model of Alzheimer's disease. Brain Res Bull 2020; 160:56-64. [PMID: 32344125 DOI: 10.1016/j.brainresbull.2020.04.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 04/13/2020] [Accepted: 04/19/2020] [Indexed: 12/14/2022]
Abstract
Extensive clinical and experimental studies established that depression and mood disorders are highly prevalent neuropsychiatric conditions in Alzheimer's disease (AD). However, its neurochemical basis is not clearly understood. Thus, understanding the neural mechanisms involved in mediating the co-morbidity of depression and AD may be crucial in exploring new pharmacological treatments for this condition. The present study investigated the role of the agmatinergic system in β-amyloid (Aββ1-42) peptide-induced depression using forced swim test (FST) in mice. Following the 28th days of its administration, Aβ1-42 peptide produced depression-like behavior in mice as evidenced by increased immobility time in FST and increased expression of pro-inflammatory cytokines like IL-6 and TNF-α compared to the control animals. The Aβ1-42 peptide-induced depression and neuroinflammatory markers were significantly inhibited by agmatine -, moxonidine, 2-BFI and l-arginine by once-daily administration during day 8-27 of the protocol. The antidepressant-like effect of agmatine in Aβ1-42 peptide in mice was potentiated by imidazoline receptor I1 agonist, moxonidine and imidazoline receptor I2 agonist 2-BFI at their sub-effective doses. On the other hand, it was completely blocked by imidazoline receptor I1 antagonist, efaroxan and imidazoline receptor I2 antagonist, idazoxan Also, agmatine levels were significantly reduced in brain samples of β-amyloid injected mice as compared to the control animals. In conclusion, the present study suggests the importance of endogenous agmatinergic system and imidazoline receptors system in β-amyloid induced a depressive-like behavior in mice. The data projects agmatine as a potential therapeutic target for the AD-associated depression and comorbidities.
Collapse
Affiliation(s)
- Nandkishor Kotagale
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India; Government College of Pharmacy, Amravati, Maharashtra 444 604, India
| | - Rupali Deshmukh
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India
| | - Madhura Dixit
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India
| | - Rajshree Fating
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India
| | - Milind Umekar
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India
| | - Brijesh Taksande
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India.
| |
Collapse
|
3
|
Chimthanawala N, Patil S, Agrawal R, Kotagale NR, Umekar MJ, Taksande BG. Inhibitory influence of agmatine in ethanol withdrawal-induced depression in rats: Behavioral and neurochemical evidence. Alcohol 2020; 83:67-74. [PMID: 31520686 DOI: 10.1016/j.alcohol.2019.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 08/20/2019] [Accepted: 09/05/2019] [Indexed: 01/06/2023]
Abstract
Although ethanol withdrawal depression is one of the prominent reasons for ethanol consumption reinstatement and ethanol dependence, its neurochemical basis is not clearly understood. The present study investigated the role of the agmatinergic system in ethanol withdrawal-induced depression using the forced swim test (FST) in rats. Chronic exposure of animals to ethanol for 21 days and its abrupt withdrawal produced depression-like behavior, as evidenced by increased immobility time in the FST, compared to the pair-fed control animals. The ethanol withdrawal-induced depression was significantly attenuated by agmatine (20-40 μg/rat, i.c.v. [intracerebroventricularly]), moxonidine (50 μg/rat, i.c.v.), 2-BFI (20 μg/rat, i.c.v.), L-arginine (80 μg/rat, i.c.v.), amino-guanidine (25 μg/rat, i.c.v.), and arcaine (50 μg/rat, i.c.v.) by their once-daily administration during the withdrawal phase (Days 21, 22, and 23). The antidepressant effect of agmatine in ethanol-withdrawn rats was potentiated by the imidazoline receptor I1 agonist moxonidine (25 μg/rat, i.c.v.) and the imidazoline receptor I2 agonist, 2-BFI (10 μg/rat, i.c.v.) at their sub-effective doses. On the other hand, it was completely blocked by the imidazoline receptor I1 antagonist, efaroxan (10 μg/rat, i.c.v.) and the imidazoline receptor I2 antagonist, idazoxan (4 μg/rat, i.c.v.). In addition, agmatine levels were significantly reduced in brain samples of ethanol-withdrawn rats as compared to the pair-fed control animals. In conclusion, the present study suggests the importance of the endogenous agmatinergic system and the imidazoline receptors system in ethanol withdrawal-induced depression. The data project agmatine as a potential therapeutic target for the alcohol withdrawal-induced depression.
Collapse
Affiliation(s)
- Niyamat Chimthanawala
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar, College of Pharmacy, New Kamptee, Nagpur (M.S.), 441 002, India
| | - Shruti Patil
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar, College of Pharmacy, New Kamptee, Nagpur (M.S.), 441 002, India
| | - Rishabh Agrawal
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar, College of Pharmacy, New Kamptee, Nagpur (M.S.), 441 002, India
| | - Nandkishor R Kotagale
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar, College of Pharmacy, New Kamptee, Nagpur (M.S.), 441 002, India; Government College of Pharmacy, Amravati (M.S.), 444 604, India
| | - Milind J Umekar
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar, College of Pharmacy, New Kamptee, Nagpur (M.S.), 441 002, India
| | - Brijesh G Taksande
- Division of Neuroscience, Department of Pharmacology, Smt. Kishoritai Bhoyar, College of Pharmacy, New Kamptee, Nagpur (M.S.), 441 002, India.
| |
Collapse
|
4
|
Chen ZD, Chen WQ, Wang ZY, Cao DN, Wu N, Li J. Antidepressant-like action of agmatine in the acute and sub-acute mouse models of depression: a receptor mechanism study. Metab Brain Dis 2018; 33:1721-1731. [PMID: 30019267 DOI: 10.1007/s11011-018-0280-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 06/22/2018] [Indexed: 01/28/2023]
Abstract
Previous studies have shown that agmatine, a potential neuromodulator or co-transmitter, exhibited antidepressant-like action in animal models, yet its mechanism, especially the receptor mechanism, remains unclear. In the present study, using efaroxan, a preferential antagonist of I1 imidazoline receptor (I1R) and yohimbine, an antagonist of α2 adrenergic receptor (α2AR), we investigated the roles of I1R and α2AR in agmatine's antidepressant-like effect in acute and sub-acute depression models in mice. We found that in the tail-suspension test (TST) and the forced swimming test (FST), acute administration of agmatine (20 and 40 mg/kg, p.o.) significantly shortened the immobility time. Concurrent administration of efaroxan (1 mg/kg, i.p.) completely abolished the antidepressant-like effects of agmatine (40 mg/kg, p.o.) whereas yohimbine (5 mg/kg, i.p.) failed to exert similar effects, suggesting that the acute antidepressant-like effects of agmatine was mainly mediated by I1R but not α2AR. Additionally, in the learned helplessness (LH) test, repeated administration of agmatine (20 mg/kg, p.o., q.d.) for 5 days significantly decreased the escape latency and the number of escape failure, and these effects were respectively abolished by concurrent administration of efaroxan (0.5 mg/kg,i.p., q.d.) and yohimbine (3 mg/kg, i.p., q.d.) for 5 days, suggesting that the antidepressant-like action of agmatine in the LH test was achieved via the activation of both I1R and α2AR. In summary, we found that the antidepressant-like effects of agmatine in the TST and the FST were mediated by activating I1R and in the sub-acute LH test were mediated by activating both I1R and α2AR.
Collapse
Affiliation(s)
- Zhao-Di Chen
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Wen-Qiang Chen
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Harvard Medical School, 200 Longwood Avenue, Boston, MA, 02115, USA
| | - Zhi-Yuan Wang
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Dan-Ni Cao
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Ning Wu
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China.
| | - Jin Li
- Beijing Key Laboratory of Neuropsychopharmacology, State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China.
| |
Collapse
|
5
|
Keller B, Mestre-Pinto JI, Álvaro-Bartolomé M, Martinez-Sanvisens D, Farre M, García-Fuster MJ, García-Sevilla JA, Torrens M. A Biomarker to Differentiate between Primary and Cocaine-Induced Major Depression in Cocaine Use Disorder: The Role of Platelet IRAS/Nischarin (I 1-Imidazoline Receptor). Front Psychiatry 2017; 8:258. [PMID: 29326609 PMCID: PMC5757145 DOI: 10.3389/fpsyt.2017.00258] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 11/13/2017] [Indexed: 12/29/2022] Open
Abstract
The association of cocaine use disorder (CUD) and comorbid major depressive disorder (MDD; CUD/MDD) is characterized by high prevalence and poor treatment outcomes. CUD/MDD may be primary (primary MDD) or cocaine-induced (CUD-induced MDD). Specific biomarkers are needed to improve diagnoses and therapeutic approaches in this dual pathology. Platelet biomarkers [5-HT2A receptor and imidazoline receptor antisera selected (IRAS)/nischarin] were assessed by Western blot in subjects with CUD and primary MDD (n = 16) or CUD-induced MDD (n = 9; antidepressant free, AD-; antidepressant treated, AD+) and controls (n = 10) at basal level and/or after acute tryptophan depletion (ATD). Basal platelet 5-HT2A receptor (monomer) was reduced in comorbid CUD/MDD subjects (all patients: 43%) compared to healthy controls, and this down-regulation was independent of AD medication (decreases in AD-: 47%, and in AD+: 40%). No basal differences were found for IRAS/nischarin contents in AD+ and AD- comorbid CUD/MDD subjects. The comparison of IRAS/nischarin in the different subject groups during/after ATD showed opposite modulations (i.e., increases and decreases) in response to low plasma tryptophan levels with significant differences discriminating between the subgroups of CUD with primary MDD and CUD-induced MDD. These specific alterations suggested that platelet IRAS/nischarin might be useful as a biomarker to discriminate between primary and CUD-induced MDD in this dual pathology.
Collapse
Affiliation(s)
- Benjamin Keller
- Laboratori de Neurofarmacologia, IUNICS, Universitat de les Illes Balears (UIB), Fundació Institut d’Investigació Sanitària Illes Balears (IdISBa), Palma, Majorca, Spain
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Joan-Ignasi Mestre-Pinto
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Hospital del Mar Medical Research Institute (IMIM), Institut de Neuropsiquiatria i addiccions (INAD), Barcelona, Spain
| | - María Álvaro-Bartolomé
- Laboratori de Neurofarmacologia, IUNICS, Universitat de les Illes Balears (UIB), Fundació Institut d’Investigació Sanitària Illes Balears (IdISBa), Palma, Majorca, Spain
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Diana Martinez-Sanvisens
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Hospital del Mar Medical Research Institute (IMIM), Institut de Neuropsiquiatria i addiccions (INAD), Barcelona, Spain
| | - Magí Farre
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Hospital del Mar Medical Research Institute (IMIM), Institut de Neuropsiquiatria i addiccions (INAD), Barcelona, Spain
- Hospital Universitari Germans Trias i Pujol (IGTP), Badalona, Spain
- Universitat Autònoma de Barcelona (UAB), Barcelona, Spain
| | - M. Julia García-Fuster
- Laboratori de Neurofarmacologia, IUNICS, Universitat de les Illes Balears (UIB), Fundació Institut d’Investigació Sanitària Illes Balears (IdISBa), Palma, Majorca, Spain
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Jesús A. García-Sevilla
- Laboratori de Neurofarmacologia, IUNICS, Universitat de les Illes Balears (UIB), Fundació Institut d’Investigació Sanitària Illes Balears (IdISBa), Palma, Majorca, Spain
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
| | - Marta Torrens
- Redes Temáticas de Investigación Cooperativa en Salud – Red de Trastornos Adictivos (RETICS-RTA), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
- Hospital del Mar Medical Research Institute (IMIM), Institut de Neuropsiquiatria i addiccions (INAD), Barcelona, Spain
- Universitat Autònoma de Barcelona (UAB), Barcelona, Spain
| |
Collapse
|
6
|
Keller B, García-Sevilla JA. Dysregulation of IRAS/nischarin and other potential I 1-imidazoline receptors in major depression postmortem brain: Downregulation of basal contents by antidepressant drug treatments. J Affect Disord 2017; 208:646-652. [PMID: 27836117 DOI: 10.1016/j.jad.2016.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 09/28/2016] [Accepted: 10/16/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Major depressive disorder (MDD) has been associated with altered brain densities of imidazoline receptors (I1-IR and I2-IR types). METHODS The contents of potential I1-IR IRAS/nischarin (167kDa) and, for comparison, those of I1- (85kDa) and I2- (45kDa and 30kDa) IR proteins were quantified by western blotting in postmortem prefrontal cortex (PFC/BA9) of antidepressant-free ([MDD(-)], n=9) and antidepressant-treated ([MDD(+)], n=12) subjects and matched controls (n=19). RESULTS In MDD, regardless of antidepressant treatment (n=21), IRAS/nischarin was not altered in PFC/BA9. However, the content of IRAS/nischarin was found modestly and not significantly increased (+19%, p=0.075) in MDD(-) and significantly decreased (-24%, p=0.001) in MDD(+), revealing that basal I1-IR content was downregulated by antidepressants. Putative 85kDa I1-IR was upregulated (+35%, p=0.035) in MDD(-) but it was not reduced (-14%, p=0.37) in MDD(+). There was a positive correlation (r=0.33, p=0.037, n=40) between the contents of IRAS/nischarin and 85kDa IR proteins in PFC/BA9 (control and MDD subjects). In MDD and regardless of antidepressants, the content of cortical 45kDa I2-IR was increased (+31%, p=0.006) and that of 30kDa I2-IR decreased (-14%, p=0.002), indicating basal dysregulations of these potential IRs. LIMITATIONS MDD(+) subjects had been treated with a variety of antidepressant drugs. The results must be understood in the context of suicide victims with MDD. CONCLUSIONS The dysregulation of IRAS/nischarin in depressed brains is a major novel finding that supports a role of this potential I1-IR in the neurobiology of MDD and in the molecular mechanisms of antidepressant drugs.
Collapse
Affiliation(s)
- Benjamin Keller
- Laboratori de Neurofarmacologia, IUNICS/IdISPa, Universitat de les Illes Balears (UIB), Palma de Mallorca, Spain; Redes Temáticas de Investigación Cooperativa en Salud-Red de Trastornos Adictivos (RETICS-RTA), ISCIII, Madrid, Spain
| | - Jesús A García-Sevilla
- Laboratori de Neurofarmacologia, IUNICS/IdISPa, Universitat de les Illes Balears (UIB), Palma de Mallorca, Spain; Redes Temáticas de Investigación Cooperativa en Salud-Red de Trastornos Adictivos (RETICS-RTA), ISCIII, Madrid, Spain.
| |
Collapse
|
7
|
Ray TS. Constructing the ecstasy of MDMA from its component mental organs: Proposing the primer/probe method. Med Hypotheses 2015; 87:48-60. [PMID: 26826641 DOI: 10.1016/j.mehy.2015.12.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 12/05/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
Abstract
The drug MDMA, commonly known as ecstasy, produces a specific and distinct open hearted mental state, which led to the creation of a new pharmacological class, "entactogens". Extensive literature on its mechanisms of action has come to characterize MDMA as a "messy" drug with multiple mechanisms, but the consensus is that the distinctive entactogenic effects arise from the release of neurotransmitters, primarily serotonin. I propose an alternative hypothesis: The entactogenic mental state is due to the simultaneous direct activation of imidazoline-1 (I1) and serotonin-2 (5-HT2) receptors by MDMA. This hypothesis emerges from "mental organ" theory, which embodies many hypotheses, the most relevant of which are: "Mental organs" are populations of neurons that all express their defining metabotropic receptor, and each mental organ plays a distinct role in the mind, a role shaped by evolution as mental organs evolve by duplication and divergence. Mental organs are the mechanism by which evolution sculpts the mind. Mental organs can be in or out of consciousness. In order for a mental organ to enter consciousness, three things must happen: The mental organ must be activated directly at its defining receptor. 5-HT2 must be simultaneously activated. One of the functions of activated 5-HT2 is to load other simultaneously activated mental organs fully into consciousness. In some cases THC must be introduced to remove long-term blocks mediated by the cannabinoid system. I propose the "primer/probe" method to test these hypotheses. A "primer" is a drug that selectively activates 5-HT2 (e.g. DOB or MEM) or serotonin-1 (5-HT1) and 5-HT2 (e.g. DOET or 2C-B-fly). A "probe" is a drug that activates a receptor whose corresponding mental organ we wish to load into consciousness in order to understand its role in the mind. The mental organ is loaded into consciousness when the primer and probe are taken together, but not when taken separately. For example, the blood pressure medications rilmenidine and moxonidine are selective for imidazoline-1 and can be used to test the hypothesis that the entactogenic mental effects of MDMA are due to loading the imidazoline-1 mental organ into consciousness. The primer/probe method is not limited to testing the specific hypothesis about MDMA and imidazoline, but is a general method for studying the role of mental organs in the mind. For example, the role of dopamine mental organs can be studied by using Parkinson's drugs such as ropinirole or pramipexole as probes.
Collapse
Affiliation(s)
- Thomas S Ray
- Department of Biology, University of Oklahoma, Norman, OK 73069, United States.
| |
Collapse
|
8
|
Kambeitz JP, Howes OD. The serotonin transporter in depression: Meta-analysis of in vivo and post mortem findings and implications for understanding and treating depression. J Affect Disord 2015; 186:358-66. [PMID: 26281039 DOI: 10.1016/j.jad.2015.07.034] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/29/2015] [Accepted: 07/28/2015] [Indexed: 12/23/2022]
Abstract
BACKGROUND Altered serotonin transporter levels have been reported in blood and brain of patients with major depressive disorders. However, the strength and consistency of the evidence for altered serotonin transporter availability in major depressive disorder is not clear. METHODS To address this, a comprehensive meta-analysis was conducted of all available in vivo neuroimaging and post mortem studies reporting serotonin transporter availability in patients with depression compared with healthy controls. RESULTS The final sample consisted of fifty (n=27 in vivo and n=25 post mortem) studies including 877 patients with depression (mean age: 42.9 years) and 968 healthy controls (mean age: 42.7 years). In vivo neuroimaging studies indicated reduced serotonin transporter binding in the striatum (g=-0.39, p=0.01), the amygdala (g=-0.37, p=0.01) and the brainstem (g=-0.31, p=0.01), including the midbrain (g=-0.27, p=0.02), but no significant alteration in the thalamus or the hippocampus. The post mortem findings indicated no significant change in serotonin transporter binding in depression in the brainstem (p=0.64), the frontal cortex (p=0.75) and the hippocampus (p=0.32, corrected for publication bias). Although there were too few studies for a meta-analysis, the post mortem studies in the amygdala and striatum showed reduced SERT binding in MDD in absolute terms, consistent with the imaging findings. LIMITATIONS A number of potential factors might have biased the results of the present meta-analysis such as the imaging modality (post mortem or in vivo neuroimaging), partial volume effects, susceptibility of some radiotracers to synaptic serotonin levels or binding to other monoamine transporters. CONCLUSIONS The results indicate that serotonin transporter availability in depressed patients is reduced in key regions of the limbic system. This provides direct support for the serotonin hypothesis of depression, and underlines the importance of the serotonin transporter as a target of pharmacological treatments.
Collapse
Affiliation(s)
- Joseph P Kambeitz
- Department of Psychosis Studies, Institute of Psychiatry, King's College London, England, United Kingdom; Department of Psychiatry, Ludwig-Maximilians-University Munich, Germany
| | - Oliver D Howes
- Department of Psychosis Studies, Institute of Psychiatry, King's College London, England, United Kingdom; Psychiatric Imaging Group, Medical Research Council Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, United Kingdom.
| |
Collapse
|
9
|
Aceros H, Farah G, Noiseux N, Mukaddam-Daher S. Moxonidine modulates cytokine signalling and effects on cardiac cell viability. Eur J Pharmacol 2014; 740:168-82. [PMID: 25036265 DOI: 10.1016/j.ejphar.2014.06.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 06/23/2014] [Accepted: 06/25/2014] [Indexed: 10/25/2022]
Abstract
Regression of left ventricular hypertrophy and improved cardiac function in SHR by the centrally acting imidazoline I1-receptor agonist, moxonidine, are associated with differential actions on circulating and cardiac cytokines. Herein, we investigated cell-type specific I1-receptor (also known as nischarin) signalling and the mechanisms through which moxonidine may interfere with cytokines to affect cardiac cell viability. Studies were performed on neonatal rat cardiomyocytes and fibroblasts incubated with interleukin (IL)-1β (5 ng/ml), tumor necrosis factor (TNF)-α (10 ng/ml), and moxonidine (10(-7) and 10(-5) M), separately and in combination, for 15 min, and 24 and 48 h for the measurement of MAPKs (ERK1/2, JNK, and p38) and Akt activation and inducible NOS (iNOS) expression, by Western blotting, and cardiac cell viability/proliferation and apoptosis by flow cytometry, MTT assay, and Live/Dead assay. Participation of imidazoline I1-receptors and the signalling proteins in the detected effects was identified using imidazoline I1-receptor antagonist and signalling protein inhibitors. The results show that IL-1β, and to a lower extent, TNF-α, causes cell death and that moxonidine protects against starvation- as well as IL-1β -induced mortality, mainly by maintaining membrane integrity, and in part, by improving mitochondrial activity. The protection involves activation of Akt, ERK1/2, p38, JNK, and iNOS. In contrast, moxonidine stimulates basal and IL-1β-induced fibroblast mortality by mechanisms that include inhibition of JNK and iNOS. Thus, apart from their actions on the central nervous system, imidazoline I1-receptors are directly involved in cardiac cell growth and death, and may play an important role in cardiovascular diseases associated with inflammation.
Collapse
Affiliation(s)
- Henry Aceros
- Centre Hospitalier de L'Université de Montréal Research Center (CRCHUM), Montreal, Québec, Canada; Department of Pharmacology, Université de Montréal, Montreal, Québec, Canada
| | - Georges Farah
- Centre Hospitalier de L'Université de Montréal Research Center (CRCHUM), Montreal, Québec, Canada; Department of Pharmacology, Université de Montréal, Montreal, Québec, Canada
| | - Nicolas Noiseux
- Centre Hospitalier de L'Université de Montréal Research Center (CRCHUM), Montreal, Québec, Canada; Department of Medicine, Université de Montréal, Montreal, Québec, Canada
| | - Suhayla Mukaddam-Daher
- Centre Hospitalier de L'Université de Montréal Research Center (CRCHUM), Montreal, Québec, Canada; Department of Pharmacology, Université de Montréal, Montreal, Québec, Canada; Department of Medicine, Université de Montréal, Montreal, Québec, Canada.
| |
Collapse
|
10
|
|
11
|
Dixit MP, Thakre PP, Pannase AS, Aglawe MM, Taksande BG, Kotagale NR. Imidazoline binding sites mediates anticompulsive-like effect of agmatine in marble-burying behavior in mice. Eur J Pharmacol 2014; 732:26-31. [PMID: 24657463 DOI: 10.1016/j.ejphar.2014.02.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 02/04/2014] [Accepted: 02/23/2014] [Indexed: 02/07/2023]
Abstract
Agmatine is a cationic amine formed by decarboxylation of l-arginine by the mitochondrial enzyme arginine decarboxylase and widely distributed in mammalian brain. Although the precise function of endogenous agmatine has been largely remained unclear, its exogenous administration demonstrated beneficial effects in several neurological and psychiatric disorders. This study was planned to examine the role of imidazoline binding sites in the anticompulsive-like effect of agmatine on marble-burying behavior. Agmatine (20 and 40mg/kg, ip), mixed imidazoline I1/α2 agonists clonidine (60µg/kg, ip) and moxonidine (0.25mg/kg, ip), and imidazoline I2 agonist 2- BFI (10mg/kg, ip) showed significant inhibition of marble burying behavior in mice. In combination studies, the anticompulsive-like effect of agmatine (10mg/kg, ip) was significantly potentiated by prior administration of moxonidine (0.25mg/kg, ip) or clonidine (30µg/kg,) or 2-BFI (5mg/kg, ip). Conversely, efaroxan (1mg/kg, ip), an I1 antagonist and idazoxan (0.25mg/kg, ip), an I2 antagonist completely blocked the anticompulsive-like effect of agmatine (10mg/kg, ip). These drugs at doses used here did not influence the basal locomotor activity in experimental animals. These results clearly indicated the involvement of imidazoline binding sites in anti-compulsive-like effect of agmatine. Thus, imidazoline binding sites can be explored further as novel therapeutic target for treatment of anxiety and obsessive compulsive disorders.
Collapse
Affiliation(s)
- Madhura P Dixit
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441002, Maharashtra, India
| | - Prajwal P Thakre
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441002, Maharashtra, India
| | - Akshay S Pannase
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441002, Maharashtra, India
| | - Manish M Aglawe
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441002, Maharashtra, India
| | - Brijesh G Taksande
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441002, Maharashtra, India
| | - Nandkishor R Kotagale
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441002, Maharashtra, India.
| |
Collapse
|
12
|
Kotagale NR, Paliwal NP, Aglawe MM, Umekar MJ, Taksande BG. Possible involvement of neuropeptide Y Y1 receptors in antidepressant like effect of agmatine in rats. Peptides 2013; 47:7-11. [PMID: 23816796 DOI: 10.1016/j.peptides.2013.04.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 04/25/2013] [Accepted: 04/27/2013] [Indexed: 11/21/2022]
Abstract
Agmatine and neuropeptide Y (NPY) are widely distributed in central nervous system and critically involved in modulation of depressive behavior in experimental animals. However their mutual interaction, if any, in regulation of depression remain largely unexplored. In the present study we explored the possible interaction between agmatine and neuropeptide Y in regulation of depression like behavior in forced swim test. We found that acute intracerebroventricular (i.c.v.) administration of agmatine (20-40μg/rat), NPY (5 and 10μg/rat) and NPY Y1 receptor agonist, [Leu(31), Pro(34)]-NPY (0.4 and 0.8ng/rat) dose dependently decreased immobility time in forced swim test indicating their antidepressant like effects. In combination studies, the antidepressant like effect of agmatine (10μg/rat) was significantly potentiated by NPY (1 and 5μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2 and 0.4ng/rat, icv) pretreatment. Conversely, pretreatment of animals with NPY Y1 receptor antagonist, BIBP3226 (0.1ng/rat, i.c.v.) completely blocked the antidepressant like effect of agmatine (20-40μg/rat) and its synergistic effect with NPY (1μg/rat, icv) or [Leu(31), Pro(34)]-NPY (0.2ng/rat, icv). The results of the present study showed that, agmatine exerts antidepressant like effects via NPYergic system possibly mediated by the NPY Y1 receptor subtypes and suggest that interaction between agmatine and neuropeptide Y may be relevant to generate the therapeutic strategies for the treatment of depression.
Collapse
Affiliation(s)
- Nandkishor R Kotagale
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur 441 002, MS, India
| | | | | | | | | |
Collapse
|
13
|
Kotagale NR, Tripathi SJ, Aglawe MM, Chopde CT, Umekar MJ, Taksande BG. Evidences for the agmatine involvement in antidepressant like effect of bupropion in mouse forced swim test. Pharmacol Biochem Behav 2013; 107:42-7. [PMID: 23583442 DOI: 10.1016/j.pbb.2013.03.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Revised: 03/25/2013] [Accepted: 03/30/2013] [Indexed: 11/19/2022]
Abstract
Although bupropion has been widely used in the treatment of depression, the precise mechanism of its therapeutic actions is not fully understood. The present study investigated the role of agmatine in an antidepressant like effect of bupropion in mouse forced swim test. The antidepressant like effect of bupropion was potentiated by pretreatment with agmatine (10-20mg/kg, ip) and by the drugs known to increase endogenous agmatine levels in brain viz., l-arginine (40 μg/mouse, icv), an agmatine biosynthetic precursor, ornithine decarboxylase inhibitor, dl-α-difluoromethyl ornithine hydrochloride, DFMO (12.5 μg/mouse, icv), diamine oxidase inhibitor, aminoguanidine (6.5 μg/mouse, icv) and agmatinase inhibitor, arcaine (50 μg/mouse, icv) as well as imidazoline I1 receptor agonists, moxonidine (0.25mg/kg, ip) and clonidine (0.015 mg/kg, ip) and imidazoline I2 receptor agonist, 2-(2-benzofuranyl)-2-imidazoline hydrochloride, 2-BFI (5mg/kg, ip). Conversely, prior administration of I1 receptor antagonist, efaroxan (1mg/kg, ip) and I2 receptor antagonist, idazoxan (0.25mg/kg, ip) blocked the antidepressant like effect of bupropion and its synergistic combination with agmatine. These results demonstrate involvement of agmatine in the antidepressant like effect of bupropion and suggest agmatine and imidazoline receptors as a potential therapeutic target for the treatment of depressive disorders.
Collapse
Affiliation(s)
- Nandkishor R Kotagale
- Division of Neuroscience, Department of Pharmacology, Shrimati Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur, Maharashtra 441 002, India
| | | | | | | | | | | |
Collapse
|
14
|
Tonello R, Villarinho JG, da Silva Sant'Anna G, Tamiozzo L, Machado P, Trevisan G, Pinto Martins MA, Ferreira J, Rubin MA. The potential antidepressant-like effect of imidazoline I2 ligand 2-BFI in mice. Prog Neuropsychopharmacol Biol Psychiatry 2012; 37:15-21. [PMID: 22122878 DOI: 10.1016/j.pnpbp.2011.11.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 10/31/2011] [Accepted: 11/14/2011] [Indexed: 12/17/2022]
Abstract
The compound 2-(2-benzofuranyl)-2-imidazoline (2-BFI) is a 2-imidazoline derivative that selectively inhibits the in vitro activity of monoamine oxidase-A and it is also an imidazoline I(2) agonist. However, the antidepressant potential of this compound and its mechanism of action have not been well defined. Therefore, in this study we investigated the antidepressant-like effect of 2-BFI in mice. 2-BFI (100 and 300μmol/kg, s.c.) significantly reduced the immobility time on the tail suspension test (TST) without changing locomotion in the open field test. The reduced the immobility time of 2-BFI (100μmol/kg, s.c.) was confirmed with the forced swimming test (FST). The antidepressant-like effect of 2-BFI (100μmol/kg, s.c.) in the TST was prevented by pretreatment with idazoxan (0.4μmol/kg, i.p., a I(2) site antagonist), methysergide (4μmol/kg, i.p., a non-selective serotonergic receptor antagonist) and haloperidol (0.1μmol/kg, i.p., a non-selective dopaminergic receptor antagonist). The anxiolytic effect of 2-BFI was also evaluated, using the elevated plus-maze test. 2-BFI (300μmol/kg, s.c.) was able to significantly increase the % of number of entries and the % of time spent in the open arms, indicating that it possesses an anxiolytic effect at high doses. In conclusion, these results suggest that the antidepressant-like effect of 2-BFI might involve serotonergic, dopaminergic and imidazoline systems, and then the imidazoline site could represent a new pharmacological target for the treatment of depression.
Collapse
Affiliation(s)
- Raquel Tonello
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica Toxicológica, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Molderings GJ, Haenisch B. Agmatine (decarboxylated l-arginine): Physiological role and therapeutic potential. Pharmacol Ther 2012; 133:351-65. [DOI: 10.1016/j.pharmthera.2011.12.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 12/05/2011] [Indexed: 01/14/2023]
|
16
|
Smith KL, Jessop DS, Finn DP. Modulation of stress by imidazoline binding sites: implications for psychiatric disorders. Stress 2009; 12:97-114. [PMID: 19006007 DOI: 10.1080/10253890802302908] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
In this review, we present evidence for the involvement of imidazoline binding sites (IBS) in modulating responses to stress, through central control of monoaminergic and hypothalamo-pituitary-adrenal (HPA) axis activity. Pharmacological and physiological evidence is presented for differential effects of different IBS subtypes on serotoninergic and catecholaminergic pathways involved in control of basal and stress-stimulated HPA axis activity. IBS ligands can modulate behavioural and neuroendocrine responses in animal models of stress, depression and anxiety, and a body of evidence exists for alterations in central IBS expression in psychiatric patients, which can be normalised partially or fully by treatment with antidepressants. Dysfunction in monoaminergic systems and the HPA axis under basal and stress-induced activation has been extensively reported in psychiatric illnesses. On the basis of the literature, we suggest a potential therapeutic role for selective IBS ligands in the treatment of depression and anxiety disorders.
Collapse
Affiliation(s)
- Karen L Smith
- Department of Pharmacology and Therapeutics, NCBES Neuroscience Cluster, National University of Ireland, Galway, Ireland
| | | | | |
Collapse
|