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Jibril TI, Alzoubi KH, Mhaidat NM, Khabour OF, Alqudah MA, Rababa’h AM, Alrabadi N, Al-udatt D. Sildenafil prevents chronic psychosocial stress-induced working memory impairment: Role of brain-derived neurotrophic factor. CURRENT RESEARCH IN PHARMACOLOGY AND DRUG DISCOVERY 2024; 6:100182. [PMID: 38706525 PMCID: PMC11067328 DOI: 10.1016/j.crphar.2024.100182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/29/2024] [Accepted: 04/12/2024] [Indexed: 05/07/2024] Open
Abstract
Background Psychosocial stress, a common feature in modern societies, impairs cognitive functions. It is suggested that stress hormones and elevated excitatory amino acids during stress are responsible for stress-induced cognitive deficits. Reduced brain-derived neurotrophic factor (BDNF) levels, increased oxidative stress, and alteration of synaptic plasticity biomarkers are also possible contributors to the negative impact of stress on learning and memory. Sildenafil citrate is a selective phosphodiesterase type 5 (PDE5) inhibitor and the first oral therapy for the treatment of erectile dysfunction. It has been shown that sildenafil improves learning and memory and possesses antioxidant properties. We hypothesized that administering sildenafil to stressed rats prevents the cognitive deficit induced by chronic psychosocial stress. Methods Psychosocial stress was generated using the intruder model. Sildenafil 3 mg/kg/day was administered intraperitoneally to animals. Behavioral studies were conducted to test spatial learning and memory using the radial arm water maze. Then, the hippocampal BDNF level and several antioxidant markers were assessed. Results This study revealed that chronic psychosocial stress impaired short-term but not long-term memory. The administration of sildenafil prevented this short-term memory impairment. Chronic psychosocial stress markedly reduced the level of hippocampal BDNF (P˂0.05), and this reduction in BDNF was normalized by sildenafil treatment. In addition, neither chronic psychosocial stress nor sildenafil significantly altered the activity of measured oxidative parameters (P > 0.05). Conclusion Chronic psychosocial stress induces short-term memory impairment. The administration of sildenafil citrate prevented this impairment, possibly by normalizing the level of BDNF.
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Affiliation(s)
- Tareq I. Jibril
- Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Karem H. Alzoubi
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy, University of Sharjah, Sharjah, United Arab Emirates
- Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Nizar M. Mhaidat
- Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Omar F. Khabour
- Department of Medical Laboratory Sciences, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Mohammad A.Y. Alqudah
- Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy, University of Sharjah, Sharjah, United Arab Emirates
- Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Abeer M. Rababa’h
- Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Nasr Alrabadi
- Department of Pharmacology, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Doaa Al-udatt
- Department of Physiology and Biochemistry, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
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da Silva ALM, Nascimento CP, Azevedo JEC, Vieira LR, Hamoy AO, Tiago ACDS, Martins Rodrigues JC, de Araujo DB, Favacho Lopes DC, de Mello VJ, Hamoy M. Unmasking hidden risks: The surprising link between PDE5 inhibitors and seizure susceptibility. PLoS One 2023; 18:e0294754. [PMID: 38033148 PMCID: PMC10688920 DOI: 10.1371/journal.pone.0294754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 11/08/2023] [Indexed: 12/02/2023] Open
Abstract
BACKGROUND Phosphodiesterase 5 inhibitors (PDE5i) are the first line treatment for erectile dysfunction; however, several articles and case reports have shown central nervous system effects, that can cause seizures in susceptible patients. This study aims to describe the changes caused by the use of Sildenafil and Tadalafil through the analysis of abnormalities expressed in the electrocorticogram (ECoG) of rats and evaluate the seizure threshold response and treatment of seizures with anticonvulsants. MATERIALS AND METHODS The study used 108 rats (Wistar). Before surgery for electrode placement in dura mater, the animals were randomly separated into 3 experiments for electrocorticogram analysis. Experiment 1: ECoG response to using PD5i (Sildenafil 20mg/kg and Tadalafil 2.6mg/kg p.o.). Experiment 2: ECoG response to the use of PD5i in association with Pentylenetetrazole (PTZ-30 mg/kg i.p.), a convulsive model. Experiment 3: ECoG response to anticonvulsant treatment (Phenytoin, Phenobarbital and Diazepam) of seizures induced by association IPDE5 + PTZ. All recordings were made thirty minutes after administration of the medication and analyzed for ten minutes, only once. We considered statistical significance level of *p<0.05, **p<0.01 and ***p < 0.001. RESULTS After administration of Sildenafil and Tadalafil, there were increases in the power of recordings in the frequency bands in oscillations in alpha (p = 0.0920) and beta (p = 0.602) when compared to the control group (p<0.001). After the use of Sildenafil and Tadalafil associated with PTZ, greater potency was observed in the recordings during seizures (p<0.001), however, the Sildenafil group showed greater potency when compared to Tadalafil (p<0.05). Phenobarbital and Diazepam showed a better response in controlling discharges triggered by the association between proconvulsant drugs. CONCLUSIONS PDE5i altered the ECoG recordings in the rats' motor cortexes, demonstrating cerebral asynchrony and potentiating the action of PTZ. These findings demonstrate that PDE5i can lower the seizure threshold.
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Affiliation(s)
- Alex Luiz Menezes da Silva
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Chirlene Pinheiro Nascimento
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Julianne Elba Cunha Azevedo
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Luana Rodrigues Vieira
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Akira Otake Hamoy
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Allan Carlos da Silva Tiago
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - João Cleiton Martins Rodrigues
- Laboratory of Experimental Neuropathology, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Daniella Bastos de Araujo
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Dielly Catrina Favacho Lopes
- Laboratory of Experimental Neuropathology, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Vanessa Jóia de Mello
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
| | - Moisés Hamoy
- Laboratory of Pharmacology and Toxicology of Natural Products, Institute of Biological Sciences, Federal University of Pará, UFPA, Belém, Pará, Brazil
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3
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Pauls MMH, Fish J, Binnie LR, Benjamin P, Betteridge S, Clarke B, Dhillon MPK, Ghatala R, Hainsworth FAH, Howe FA, Khan U, Kruuse C, Madigan JB, Moynihan B, Patel B, Pereira AC, Rostrup E, Shtaya ABY, Spilling CA, Trippier S, Williams R, Young R, Barrick TR, Isaacs JD, Hainsworth AH. Testing the cognitive effects of tadalafil. Neuropsychological secondary outcomes from the PASTIS trial. CEREBRAL CIRCULATION - COGNITION AND BEHAVIOR 2023; 5:100187. [PMID: 37811523 PMCID: PMC10550803 DOI: 10.1016/j.cccb.2023.100187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 10/10/2023]
Abstract
Cerebral small vessel disease (SVD) is a major cause of cognitive impairment in older people. As secondary endpoints in a phase-2 randomised clinical trial, we tested the effects of single administration of a widely-used PDE5 inhibitor, tadalafil, on cognitive performance in older people with SVD. In a double-blinded, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥ 7 days apart (randomised to order of treatment). The Montreal Cognitive Assessment (MOCA) was administered at baseline, alongside a measure to estimate optimal intellectual ability (Test of Premorbid Function). Then, before and after treatment, a battery of neuropsychological tests was administered, assessing aspects of attention, information processing speed, working memory and executive function. Sixty-five participants were recruited and 55 completed the protocol (N = 55, age: 66.8 (8.6) years, range 52-87; 15/40 female/male). Median MOCA score was 26 (IQR: 23, 27], range 15-30). No significant treatment effects were seen in any of the neuropsychological tests. There was a trend towards improved performance on Digit Span Forward (treatment effect 0.37, C.I. 0.01, 0.72; P = 0.0521). We did not identify significant treatment effects of single-administration tadalafil on neuropsychological performance in older people with SVD. The trend observed on Digit Span Forward may help to inform future studies. Clinical trial registration http://www.clinicaltrials.gov. Unique identifier: NCT00123456, https://eudract.ema.europa.eu. Unique identifier: 2015-001,235-20NCT00123456.
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Affiliation(s)
- Mathilde MH Pauls
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Jessica Fish
- Neuropsychology, St George's University Hospitals NHS Foundation Trust, London, UK
- School of Health & Wellbeing, University of Glasgow, UK
| | - Lauren R Binnie
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
| | - Philip Benjamin
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
- Neuroradiology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Shai Betteridge
- Neuropsychology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Brian Clarke
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | | | - Rita Ghatala
- South London Stroke Research Network, London, UK
| | | | - Franklyn A Howe
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
| | - Usman Khan
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Christina Kruuse
- Department of Neurology and Neurovascular Research Unit, Herlev Gentofte Hospital, Denmark
| | - Jeremy B Madigan
- Neuroradiology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Barry Moynihan
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
- Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland
| | - Bhavini Patel
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Anthony C Pereira
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Egill Rostrup
- Mental Health Centre, University of Copenhagen, Glostrup, Denmark
| | - Anan BY Shtaya
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
| | - Catherine A Spilling
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
| | | | | | - Robin Young
- Robertson Centre for Biostatistics, University of Glasgow, UK
| | - Thomas R Barrick
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
| | - Jeremy D Isaacs
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
| | - Atticus H Hainsworth
- Molecular & Clinical Sciences Research Institute, St George's University of London, UK
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, UK
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4
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Hainsworth AH, Arancio O, Elahi FM, Isaacs JD, Cheng F. PDE5 inhibitor drugs for use in dementia. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2023; 9:e12412. [PMID: 37766832 PMCID: PMC10520293 DOI: 10.1002/trc2.12412] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/07/2023] [Accepted: 07/08/2023] [Indexed: 09/29/2023]
Abstract
Alzheimer's disease and related dementias (ADRD) remain a major health-care challenge with few licensed medications. Repurposing existing drugs may afford prevention and treatment. Phosphodiesterase-5 (PDE5) is widely expressed in vascular myocytes, neurons, and glia. Potent, selective, Food and Drug Administration-approved PDE5 inhibitors are already in clinical use (sildenafil, vardenafil, tadalafil) as vasodilators in erectile dysfunction and pulmonary arterial hypertension. Animal data indicate cognitive benefits of PDE5 inhibitors. In humans, real-world patient data suggest that sildenafil and vardenafil are associated with reduced dementia risk. While a recent clinical trial of acute tadalafil on cerebral blood flow was neutral, there may be chronic actions of PDE5 inhibition on cerebrovascular or synaptic function. We provide a perspective on the potential utility of PDE5 inhibitors for ADRD. We conclude that further prospective clinical trials with PDE5 inhibitors are warranted. The choice of drug will depend on brain penetration, tolerability in older people, half-life, and off-target effects. HIGHLIGHTS Potent phosphodiesterase-5 (PDE5) inhibitors are in clinical use as vasodilators.In animals PDE5 inhibitors enhance synaptic function and cognitive ability.In humans the PDE5 inhibitor sildenafil is associated with reduced risk of Alzheimer's disease.Licensed PDE5 inhibitors have potential for repurposing in dementia.Prospective clinical trials of PDE5 inhibitors are warranted.
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Affiliation(s)
- Atticus H. Hainsworth
- Molecular & Clinical Sciences Research InstituteSt George's University of LondonLondonUK
- Department of NeurologySt George's University Hospitals NHS Foundation TrustLondonUK
| | - Ottavio Arancio
- Department of Pathology and Cell BiologyTaub Institute for Research on Alzheimer's Disease and the Aging BrainDepartment of MedicineColumbia UniversityNew YorkNew YorkUSA
| | - Fanny M. Elahi
- Departments of Neurology and NeuroscienceRonald M. Loeb Center for Alzheimer's DiseaseFriedman Brain InstituteIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Jeremy D. Isaacs
- Molecular & Clinical Sciences Research InstituteSt George's University of LondonLondonUK
- Department of NeurologySt George's University Hospitals NHS Foundation TrustLondonUK
| | - Feixiong Cheng
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOhioUSA
- Department of Molecular MedicineCleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOhioUSA
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5
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Sadeghi MA, Nassireslami E, Yousefi Zoshk M, Hosseini Y, Abbasian K, Chamanara M. Phosphodiesterase inhibitors in psychiatric disorders. Psychopharmacology (Berl) 2023; 240:1201-1219. [PMID: 37060470 DOI: 10.1007/s00213-023-06361-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 03/27/2023] [Indexed: 04/16/2023]
Abstract
RATIONALE Challenges in drug development for psychiatric disorders have left much room for the introduction of novel treatments with better therapeutic efficacies and indices. As a result, intense research has focused on identifying new targets for developing such pharmacotherapies. One of these targets may be the phosphodiesterase (PDE) class of enzymes, which play important roles in intracellular signaling. Due to their critical roles in cellular pathways, these enzymes affect diverse neurobiological functions from learning and memory formation to neuroinflammation. OBJECTIVES In this paper, we reviewed studies on the use of PDE inhibitors (PDEIs) in preclinical models and clinical trials of psychiatric disorders including depression, anxiety, schizophrenia, post-traumatic stress disorder (PTSD), bipolar disorder (BP), sexual dysfunction, and feeding disorders. RESULTS PDEIs are able to improve symptoms of psychiatric disorders in preclinical models through activating the cAMP-PKA-CREB and cGMP-PKG pathways, attenuating neuroinflammation and oxidative stress, and stimulating neural plasticity. The most promising therapeutic candidates to emerge from these preclinical studies are PDE2 and PDE4 inhibitors for depression and anxiety and PDE1 and PDE10 inhibitors for schizophrenia. Furthermore, PDE3 and 4 inhibitors have shown promising results in clinical trials in patients with depression and schizophrenia. CONCLUSIONS Larger and better designed clinical studies of PDEIs in schizophrenia, depression, and anxiety are warranted to facilitate their translation into the clinic. Regarding the other conditions discussed in this review (most notably PTSD and BP), better characterization of the effects of PDEIs in preclinical models is required before clinical studies.
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Affiliation(s)
- Mohammad Amin Sadeghi
- Toxicology Research Center, AJA University of Medical Sciences, Tehran, Iran
- Department of Pharmacology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Ehsan Nassireslami
- Toxicology Research Center, AJA University of Medical Sciences, Tehran, Iran
- Department of Pharmacology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Mojtaba Yousefi Zoshk
- Trauma Research Center, AJA University of Medical Sciences, Tehran, Iran
- Department of Pediatrics, AJA University of Medical Sciences, Tehran, Iran
| | - Yasaman Hosseini
- Cognitive Neuroscience Center, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Kourosh Abbasian
- Management and Health Economics Department, AJA University of Medical Sciences, Tehran, Iran
| | - Mohsen Chamanara
- Toxicology Research Center, AJA University of Medical Sciences, Tehran, Iran.
- Department of Pharmacology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran.
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Hudwekar AD, Kotwal P, Dar MI, Balgotra S, Dogra A, Kour J, Chobe SS, Nandi U, Hussain Syed S, Sawant SD. Pyrazolopyrimidinone Based Selective Inhibitors of PDE5 for the Treatment of Erectile Dysfunction. Chem Biodivers 2023; 20:e202200707. [PMID: 36915218 DOI: 10.1002/cbdv.202200707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 03/12/2023] [Accepted: 03/13/2023] [Indexed: 03/16/2023]
Abstract
Continuing research with our earlier finding of sildenafil based analogs in the search of new inhibitors of PDE5 for erectile dysfunction suggested that there is a scope of modifications at N-methylpiperazine ring with hydrophobic region followed by hydrogen bond donor or acceptor region. However, the leads identified earlier had some limitations like poor pharmacokinetic (PK) profile, low aqueous solubility and poor bioavailability. In this direction, a new series of sildenafil based analogs were designed, synthesized and screened for their PDE5 inhibitory activity. In this series compound 18 was found to have excellent in vitro activity with selectivity towards PDE5 isozyme, also the in vivo activity and pharmacokinetic profile was excellent. The cyp inhibition and CaCO2 permeability was also excellent for compound 18.
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Affiliation(s)
- Abhinandan D Hudwekar
- Natural Products and Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
- Department of Biochemistry, Vanderbilt University, School of Medicine, Nashville, Tennessee, 37232-0146, United States
| | - Pankul Kotwal
- PK-PD Tox Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Mohd Ishaq Dar
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Sanat Nagar, Srinagar- 190005, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Shilpi Balgotra
- Natural Products and Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
- Department of Chemistry, Central University of Jammu, Bagla Suchani, 181143, UT of J&K, India
| | - Ashish Dogra
- PK-PD Tox Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Jaspreet Kour
- Natural Products and Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Santosh S Chobe
- Department of Chemistry, Loknete Vyankatrao Hiray Arts, Science and Commerce College, Nashik, 422003, Maharashtra, India
| | - Utpal Nandi
- PK-PD Tox Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Sajad Hussain Syed
- Pharmacology Division, CSIR-Indian Institute of Integrative Medicine, Sanat Nagar, Srinagar- 190005, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Sanghapal D Sawant
- Natural Products and Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, UT of J&K, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
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7
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Zagórska A, Czopek A, Fryc M, Jaromin A, Boyd BJ. Drug Discovery and Development Targeting Dementia. Pharmaceuticals (Basel) 2023; 16:151. [PMID: 37259302 PMCID: PMC9965722 DOI: 10.3390/ph16020151] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/16/2023] [Accepted: 01/16/2023] [Indexed: 08/04/2023] Open
Abstract
Dementia, most often associated with neurodegenerative diseases, affects millions of people worldwide, predominantly the elderly. Unfortunately, no treatment is still available. Therefore, there is an urgent need to address this situation. This review presents the state of the art of drug discovery and developments in targeting dementia. Several approaches are discussed, such as drug repurposing, the use of small molecules, and phosphodiesterase inhibitors. Furthermore, the review also provides insights into clinical trials of these molecules. Emphasis has been placed on small molecules and multi-target-directed ligands, as well as disease-modifying therapies. Finally, attention is drawn to the possibilities of applications of nanotechnology in managing dementia.
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Affiliation(s)
- Agnieszka Zagórska
- Department of Medicinal Chemistry, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland
| | - Anna Czopek
- Department of Medicinal Chemistry, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland
| | - Monika Fryc
- Department of Medicinal Chemistry, Jagiellonian University Medical College, Medyczna 9, 30-688 Kraków, Poland
| | - Anna Jaromin
- Department of Lipids and Liposomes, Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14a, 50-383 Wrocław, Poland
| | - Ben J. Boyd
- Department of Pharmacy, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University (Parkville Campus), 381 Royal Parade, Parkville, VIC 3052, Australia
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8
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Tropea MR, Gulisano W, Vacanti V, Arancio O, Puzzo D, Palmeri A. Nitric oxide/cGMP/CREB pathway and amyloid-beta crosstalk: From physiology to Alzheimer's disease. Free Radic Biol Med 2022; 193:657-668. [PMID: 36400326 DOI: 10.1016/j.freeradbiomed.2022.11.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/30/2022] [Accepted: 11/12/2022] [Indexed: 11/17/2022]
Abstract
The nitric oxide (NO)/cGMP pathway has been extensively studied for its pivotal role in synaptic plasticity and memory processes, resulting in an increase of cAMP response element-binding (CREB) phosphorylation, and consequent synthesis of plasticity-related proteins. The NO/cGMP/CREB signaling is downregulated during aging and neurodegenerative disorders and is affected by Amyloid-β peptide (Aβ) and tau protein, whose increase and deposition is considered the key pathogenic event of Alzheimer's disease (AD). On the other hand, in physiological conditions, the crosstalk between the NO/cGMP/PKG/CREB pathway and Aβ ensures long-term potentiation and memory formation. This review summarizes the current knowledge on the interaction between the NO/cGMP/PKG/CREB pathway and Aβ in the healthy and diseased brain, offering a new perspective to shed light on AD pathophysiology. We will focus on the synaptic mechanisms underlying Aβ physiological interplay with cGMP pathway and how this balance is corrupted in AD, as high levels of Aβ interfere with NO production and cGMP molecular signaling leading to cognitive impairment. Finally, we will discuss results from preclinical and clinical studies proposing the increase of cGMP signaling as a therapeutic strategy in the treatment of AD.
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Affiliation(s)
- Maria Rosaria Tropea
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, 95123, Italy
| | - Walter Gulisano
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, 95123, Italy
| | - Valeria Vacanti
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, 95123, Italy
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, USA; Department of Pathology & Cell Biology and Department of Medicine, Columbia University, New York, NY, 10032, USA
| | - Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, 95123, Italy; Oasi Research Institute-IRCCS, Troina (EN), 94018, Italy.
| | - Agostino Palmeri
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, 95123, Italy
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9
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Morén C, Treder N, Martínez-Pinteño A, Rodríguez N, Arbelo N, Madero S, Gómez M, Mas S, Gassó P, Parellada E. Systematic Review of the Therapeutic Role of Apoptotic Inhibitors in Neurodegeneration and Their Potential Use in Schizophrenia. Antioxidants (Basel) 2022; 11:2275. [PMID: 36421461 PMCID: PMC9686909 DOI: 10.3390/antiox11112275] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 09/15/2023] Open
Abstract
Schizophrenia (SZ) is a deleterious brain disorder affecting cognition, emotion and reality perception. The most widely accepted neurochemical-hypothesis is the imbalance of neurotransmitter-systems. Depleted GABAergic-inhibitory function might produce a regionally-located dopaminergic and glutamatergic-storm in the brain. The dopaminergic-release may underlie the positive psychotic-symptoms while the glutamatergic-release could prompt the primary negative symptoms/cognitive deficits. This may occur due to excessive synaptic-pruning during the neurodevelopmental stages of adolescence/early adulthood. Thus, although SZ is not a neurodegenerative disease, it has been suggested that exaggerated dendritic-apoptosis could explain the limited neuroprogression around its onset. This apoptotic nature of SZ highlights the potential therapeutic action of anti-apoptotic drugs, especially at prodromal stages. If dysregulation of apoptotic mechanisms underlies the molecular basis of SZ, then anti-apoptotic molecules could be a prodromal therapeutic option to halt or prevent SZ. In fact, risk alleles related in apoptotic genes have been recently associated to SZ and shared molecular apoptotic changes are common in the main neurodegenerative disorders and SZ. PRISMA-guidelines were considered. Anti-apoptotic drugs are commonly applied in classic neurodegenerative disorders with promising results. Despite both the apoptotic-hallmarks of SZ and the widespread use of anti-apoptotic targets in neurodegeneration, there is a strikingly scarce number of studies investigating anti-apoptotic approaches in SZ. We analyzed the anti-apoptotic approaches conducted in neurodegeneration and the potential applications of such anti-apoptotic therapies as a promising novel therapeutic strategy, especially during early stages.
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Affiliation(s)
- Constanza Morén
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- U722 Group, Centro de Investigación Biomédica en Red de Enfermedades Raras, CIBERER, Carlos III Health Institute, 28029 Madrid, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
| | - Nina Treder
- Faculty of Psychology and Neuroscience, Maastricht University, 6211 LK Maastricht, The Netherlands
| | - Albert Martínez-Pinteño
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
| | - Natàlia Rodríguez
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
| | - Néstor Arbelo
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Santiago Madero
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Marta Gómez
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
- Department of Psychiatry, Servizo Galego de Saúde (SERGAS), 36001 Pontevedra, Spain
| | - Sergi Mas
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Patricia Gassó
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
| | - Eduard Parellada
- Barcelona Clínic Schizophrenia Unit (BCSU), Institute of Neuroscience, Psychiatry and Psychology Service, Hospital Clínic of Barcelona, University of Barcelona, 08036 Barcelona, Spain
- Clinical and Experimental Neuroscience Area, The August Pi i Sunyer Biomedical Research Institute (IDIBAPS), 08036 Barcelona, Spain
- Department of Basic Clinical Practice, Pharmacology Unit, University of Barcelona, 08036 Barcelona, Spain
- G04 Group, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Carlos III Health Institute, 28029 Madrid, Spain
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10
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Leukes VN, Malherbe ST, Hiemstra A, Kotze LA, Roos K, Keyser A, De Swardt D, Gutschmidt A, Walzl G, du Plessis N. Sildenafil, a Type-5 Phosphodiesterase Inhibitor, Fails to Reverse Myeloid-Derived Suppressor Cell-Mediated T Cell Suppression in Cells Isolated From Tuberculosis Patients. Front Immunol 2022; 13:883886. [PMID: 35935981 PMCID: PMC9353143 DOI: 10.3389/fimmu.2022.883886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 06/24/2022] [Indexed: 11/13/2022] Open
Abstract
Successful TB treatment is hampered by increasing resistance to the two most effective first-line anti-TB drugs, namely isoniazid and rifampicin, thus innovative therapies focused on host processes, termed host-directed therapies (HDTs), are promising novel approaches for increasing treatment efficacy without inducing drug resistance. We assessed the ability of Sildenafil, a type-5 phosphodiesterase inhibitor, as a repurposed compound, to serve as HDT target, by counteracting the suppressive effects of myeloid-derived suppressor cells (MDSC) obtained from active TB cases on T-cell responsiveness. We confirm that MDSC suppress non-specific T-cell activation. We also show that Sildenafil treatment fails to reverse the MDSC-mediated suppression of T-cell functions measured here, namely activation and proliferation. The impact of Sildenafil treatment on improved immunity, using the concentration tested here, is likely to be minimal, but further identification and development of MDSC-targeting TB host-directed therapies are warranted.
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Affiliation(s)
- Vinzeigh N. Leukes
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Stephanus T. Malherbe
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Andriette Hiemstra
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Leigh A. Kotze
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Kelly Roos
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Alana Keyser
- Division of Medical Virology, Department of Pathology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Dalene De Swardt
- Central Analytical Facility, Stellenbosch University, Cape Town, South Africa
| | - Andrea Gutschmidt
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Gerhard Walzl
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Nelita du Plessis
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medical and Health Sciences, Stellenbosch University, Cape Town, South Africa
- *Correspondence: Nelita du Plessis,
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11
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Taoro-González L, Cabrera-Pastor A, Sancho-Alonso M, Felipo V. Intracellular and extracelluar cyclic GMP in the brain and the hippocampus. VITAMINS AND HORMONES 2022; 118:247-288. [PMID: 35180929 DOI: 10.1016/bs.vh.2021.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cyclic Guanosine-Monophosphate (cGMP) is implicated as second messenger in a plethora of pathways and its effects are executed mainly by cGMP-dependent protein kinases (PKG). It is involved in both peripheral (cardiovascular regulation, intestinal secretion, phototransduction, etc.) and brain (hippocampal synaptic plasticity, neuroinflammation, cognitive function, etc.) processes. Stimulation of hippocampal cGMP signaling have been proved to be beneficial in animal models of aging, Alzheimer's disease or hepatic encephalopathy, restoring different cognitive functions such as passive avoidance, object recognition or spatial memory. However, even when some inhibitors of cGMP-degrading enzymes (PDEs) are already used against peripheral pathologies, their utility as neurological treatments is still under clinical investigation. Additionally, it has been demonstrated a list of cGMP roles as not second but first messenger. The role of extracellular cGMP has been specially studied in hippocampal function and cognitive impairment in animal models and it has emerged as an important modulator of neuroinflammation-mediated cognitive alterations and hippocampal synaptic plasticity malfunction. Specifically, it has been demonstrated that extracellular cGMP decreases hippocampal IL-1β levels restoring membrane expression of glutamate receptors in the hippocampus and cognitive function in hyperammonemic rats. The mechanisms implicated are still unclear and might involve complex interactions between hippocampal neurons, astrocytes and microglia. Membrane targets for extracellular cGMP are still poorly understood and must be addressed in future studies.
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Affiliation(s)
- Lucas Taoro-González
- Department of Clinical Psychology, Psychobiology and Methodology, Area of Psycobiology, University of La Laguna, Tenerife, Spain
| | - Andrea Cabrera-Pastor
- Fundación Investigación Hospital Clínico, Instituto de Investigación Sanitaria (INCLIVA), Valencia, Spain; Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - María Sancho-Alonso
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Príncipe Felipe, Valencia, Spain.
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Memory Enhancers for Alzheimer's Dementia: Focus on cGMP. Pharmaceuticals (Basel) 2021; 14:ph14010061. [PMID: 33451088 PMCID: PMC7828493 DOI: 10.3390/ph14010061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 02/06/2023] Open
Abstract
Cyclic guanosine-3',5'-monophosphate, better known as cyclic-GMP or cGMP, is a classical second messenger involved in a variety of intracellular pathways ultimately controlling different physiological functions. The family of guanylyl cyclases that includes soluble and particulate enzymes, each of which comprises several isoforms with different mechanisms of activation, synthesizes cGMP. cGMP signaling is mainly executed by the activation of protein kinase G and cyclic nucleotide gated channels, whereas it is terminated by its hydrolysis to GMP operated by both specific and dual-substrate phosphodiesterases. In the central nervous system, cGMP has attracted the attention of neuroscientists especially for its key role in the synaptic plasticity phenomenon of long-term potentiation that is instrumental to memory formation and consolidation, thus setting off a "gold rush" for new drugs that could be effective for the treatment of cognitive deficits. In this article, we summarize the state of the art on the neurochemistry of the cGMP system and then review the pre-clinical and clinical evidence on the use of cGMP enhancers in Alzheimer's disease (AD) therapy. Although preclinical data demonstrates the beneficial effects of cGMP on cognitive deficits in AD animal models, the results of the clinical studies carried out to date are not conclusive. More trials with a dose-finding design on selected AD patient's cohorts, possibly investigating also combination therapies, are still needed to evaluate the clinical potential of cGMP enhancers.
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Ribaudo G, Ongaro A, Zagotto G, Memo M, Gianoncelli A. Therapeutic Potential of Phosphodiesterase Inhibitors against Neurodegeneration: The Perspective of the Medicinal Chemist. ACS Chem Neurosci 2020; 11:1726-1739. [PMID: 32401481 PMCID: PMC8007108 DOI: 10.1021/acschemneuro.0c00244] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
![]()
Increasing human
life expectancy prompts the development of novel
remedies for cognitive decline: 44 million people worldwide are affected
by dementia, and this number is predicted to triple by 2050. Acetylcholinesterase
and N-methyl-d-aspartate receptors represent
the targets of currently available drugs for Alzheimer’s disease,
which are characterized by limited efficacy. Thus, the search for
therapeutic agents with alternative or combined mechanisms of action
is wide open. Since variations in 3′,5′-cyclic adenosine
monophosphate, 3′,5′-cyclic guanosine monophosphate,
and/or nitric oxide levels interfere with downstream pathways involved
in memory processes, evidence supporting the potential of phosphodiesterase
(PDE) inhibitors in contrasting neurodegeneration should be
critically considered. For the preparation of this Review, more than
140 scientific papers were retrieved by searching PubMed and Scopus
databases. A systematic approach was adopted when overviewing the
different PDE isoforms, taking into account details on brain localization,
downstream molecular mechanisms, and inhibitors currently under study,
according to available in vitro and in vivo data. In the context of drug repurposing, a section focusing on
PDE5 was introduced. Original computational studies were performed
to rationalize the emerging evidence that suggests the role of PDE5
inhibitors as multi-target agents against neurodegeneration.
Moreover, since such compounds must cross the blood–brain barrier
and reach inhibitory concentrations in the central nervous system
to exert their therapeutic activity, physicochemical parameters
were analyzed and discussed. Taken together, literature and computational
data suggest that some PDE5 inhibitors, such as tadalafil, represent
promising candidates.
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Affiliation(s)
- Giovanni Ribaudo
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Alberto Ongaro
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Giuseppe Zagotto
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Maurizio Memo
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Alessandra Gianoncelli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
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Leukes V, Walzl G, du Plessis N. Myeloid-Derived Suppressor Cells as Target of Phosphodiesterase-5 Inhibitors in Host-Directed Therapeutics for Tuberculosis. Front Immunol 2020; 11:451. [PMID: 32269568 PMCID: PMC7109258 DOI: 10.3389/fimmu.2020.00451] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 02/27/2020] [Indexed: 01/11/2023] Open
Abstract
Resistance toward current and new classes of anti-tuberculosis (anti-TB) antibiotics are rapidly emerging; thus, innovative therapies focused on host processes, termed host-directed therapies (HDTs), are promising novel approaches for shortening therapy regimens without inducing drug resistance. Development of new TB drugs is lengthy and expensive, and success is not guaranteed; thus, alternatives are needed. Repurposed drugs have already passed Food and Drug Administration (FDA) as well as European Medicines Agency (EMA) safety requirements and may only need to prove efficacy against Mycobacterium tuberculosis (M.tb). Phosphodiesterases (PDEs) hydrolyze the catalytic breakdown of both cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) to their inactive mononucleotides. Advances in molecular pharmacology have identified 11 PDE families; and the success of sildenafil, a PDE-5 selective inhibitor (PDE-5i), in treating pulmonary hypertension and erectile dysfunction has invigorated research into the therapeutic potential of selective PDE inhibitors in other conditions. Myeloid-derived suppressor cells (MDSCs) suppress anti-TB T-cell responses, likely contributing to TB disease progression. PDE-5i increases cGMP within MDSC resulting in the downregulation of arginase-1 (ARG1) and nitric oxide synthase 2 (NOS2), reducing MDSC's suppressive potential. The effect of this reduction decreases MDSC-induced T-cell-suppressive mechanisms. This review highlights the possibility of HDT targeting of MDSC, using a PDE-5i in combination with the current TB regimen, resulting in improved TB treatment efficacy.
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Affiliation(s)
- Vinzeigh Leukes
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
| | - Gerhard Walzl
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
| | - Nelita du Plessis
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council for Tuberculosis Research, Stellenbosch University, Cape Town, South Africa
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15
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Duarte-Silva E, Filho AJMC, Barichello T, Quevedo J, Macedo D, Peixoto C. Phosphodiesterase-5 inhibitors: Shedding new light on the darkness of depression? J Affect Disord 2020; 264:138-149. [PMID: 32056743 DOI: 10.1016/j.jad.2019.11.114] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 11/22/2019] [Accepted: 11/26/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Phosphodiesterase-5 inhibitors (PDE5Is) are used to treat erectile dysfunction (ED). Recently, the antidepressant-like effect of PDE5Is was demonstrated in animal models of depression. In clinical settings, PDE5Is were studied only for ED associated depression. Hence, there are no studies evaluating the effects of PDE5Is for the treatment of major depressive disorder (MDD) without ED. In this review article, we aimed to discuss the use of PDE5Is in the context of MDD, highlighting the roles of PDE genes in the development of MDD, the potential mechanisms by which PDE5Is can be beneficial for MDD and the potentials and limitations of PDE5Is repurposing to treat MDD. METHODS We used PubMed (MEDLINE) database to collect the studies cited in this review. Papers written in English language regardless the year of publication were selected. RESULTS A few preclinical studies support the antidepressant-like activity of PDE5Is. Clinical studies in men with ED and depression suggest that PDE5Is improve depressive symptoms. No clinical studies were conducted in subjects suffering from depression without ED. Antidepressant effect of PDE5Is may be explained by multiple mechanisms including inhibition of brain inflammation and modulation of neuroplasticity. LIMITATIONS The low number of preclinical and absence of clinical studies to support the antidepressant effect of PDE5Is. CONCLUSIONS No clinical trial was conducted to date evaluating PDE5Is in depressed patients without ED. PDE5Is' anti-inflammatory and neuroplasticity mechanisms may justify the potential antidepressant effect of these drugs. Despite this, clinical trials evaluating their efficacy in depressed patients need to be conducted.
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Affiliation(s)
- Eduardo Duarte-Silva
- Laboratory of Ultrastructure, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (FIOCRUZ-PE), Recife, PE, Brazil; Graduate Program in Biosciences and Biotechnology for Health (PPGBBS), Aggeu Magalhães Institute (IAM), Recife, PE, Brazil.
| | - Adriano José Maia Chaves Filho
- Neuropsychopharmacology Laboratory, Drug Research and Development Center, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, CE, Brazil
| | - Tatiana Barichello
- Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, 1941 East Road, Houston, TX 77054, United States; Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina-UNESC, Criciúma, SC, Brazil; Center of Excellence on Mood Disorders, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.
| | - João Quevedo
- Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, 1941 East Road, Houston, TX 77054, United States; Laboratory of Neurosciences, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina-UNESC, Criciúma, SC, Brazil; Center of Excellence on Mood Disorders, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States.
| | - Danielle Macedo
- Neuropsychopharmacology Laboratory, Drug Research and Development Center, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, CE, Brazil; Department of Physiology and Pharmacology, Faculty of Medicine, Universidade Federal do Ceará, Fortaleza, CE, Brazil; National Institute for Translational Medicine (INCT-TM, CNPq), Ribeirão Preto, Brazil
| | - Christina Peixoto
- Laboratory of Ultrastructure, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (FIOCRUZ-PE), Recife, PE, Brazil; National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil.
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16
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Zuccarello E, Acquarone E, Calcagno E, Argyrousi EK, Deng SX, Landry DW, Arancio O, Fiorito J. Development of novel phosphodiesterase 5 inhibitors for the therapy of Alzheimer's disease. Biochem Pharmacol 2020; 176:113818. [PMID: 31978378 DOI: 10.1016/j.bcp.2020.113818] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/14/2020] [Indexed: 12/13/2022]
Abstract
Nitric oxide (NO) is a gaseous molecule that plays a multifactorial role in several cellular processes. In the central nervous system, the NO dual nature in neuroprotection and neurotoxicity has been explored to unveil its involvement in Alzheimer's disease (AD). A growing body of research shows that the activation of the NO signaling pathway leading to the phosphorylation of the transcription factor cyclic adenine monophosphate responsive element binding protein (CREB) (so-called NO/cGMP/PKG/CREB signaling pathway) ameliorates altered neuroplasticity and memory deficits in AD animal models. In addition to NO donors, several other pharmacological agents, such as phosphodiesterase 5 (PDE5) inhibitors have been used to activate the pathway and rescue memory disorders. PDE5 inhibitors, including sildenafil, tadalafil and vardenafil, are marketed for the treatment of erectile dysfunction and arterial pulmonary hypertension due to their vasodilatory properties. The ability of PDE5 inhibitors to interfere with the NO/cGMP/PKG/CREB signaling pathway by increasing the levels of cGMP has prompted the hypothesis that PDE5 inhibition might be used as an effective therapeutic strategy for the treatment of AD. To this end, newly designed PDE5 inhibitors belonging to different chemical classes with improved pharmacologic profile (e.g. higher potency, improved selectivity, and blood-brain barrier penetration) have been synthesized and evaluated in several animal models of AD. In addition, recent medicinal chemistry effort has led to the development of agents concurrently acting on the PDE5 enzyme and a second target involved in AD. Both marketed and investigational PDE5 inhibitors have shown to reverse cognitive defects in young and aged wild type mice as well as transgenic mouse models of AD and tauopathy using a variety of behavioral tasks. These studies confirmed the therapeutic potential of PDE5 inhibitors as cognitive enhancers. However, clinical studies assessing cognitive functions using marketed PDE5 inhibitors have not been conclusive. Drug discovery efforts by our group and others are currently directed towards the development of novel PDE5 inhibitors tailored to AD with improved pharmacodynamic and pharmacokinetic properties. In summary, the present perspective reports an overview of the correlation between the NO signaling and AD, as well as an outline of the PDE5 inhibitors used as an alternative approach in altering the NO pathway leading to an improvement of learning and memory. The last two sections describe the preclinical and clinical evaluation of PDE5 inhibitors for the treatment of AD, providing a comprehensive analysis of the current status of the AD drug discovery efforts involving PDE5 as a new therapeutic target.
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Affiliation(s)
- Elisa Zuccarello
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Erica Acquarone
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Elisa Calcagno
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Elentina K Argyrousi
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States
| | - Shi-Xian Deng
- Department of Medicine, Columbia University, New York, NY, United States
| | - Donald W Landry
- Department of Medicine, Columbia University, New York, NY, United States
| | - Ottavio Arancio
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States; Department of Medicine, Columbia University, New York, NY, United States; Department of Pathology and Cell Biology, Columbia University, New York, NY, United States.
| | - Jole Fiorito
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, United States; Department of Biological and Chemical Sciences, New York Institute of Technology, Old Westbury, NY, United States.
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17
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Baillie GS, Tejeda GS, Kelly MP. Therapeutic targeting of 3',5'-cyclic nucleotide phosphodiesterases: inhibition and beyond. Nat Rev Drug Discov 2019; 18:770-796. [PMID: 31388135 PMCID: PMC6773486 DOI: 10.1038/s41573-019-0033-4] [Citation(s) in RCA: 181] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2019] [Indexed: 01/24/2023]
Abstract
Phosphodiesterases (PDEs), enzymes that degrade 3',5'-cyclic nucleotides, are being pursued as therapeutic targets for several diseases, including those affecting the nervous system, the cardiovascular system, fertility, immunity, cancer and metabolism. Clinical development programmes have focused exclusively on catalytic inhibition, which continues to be a strong focus of ongoing drug discovery efforts. However, emerging evidence supports novel strategies to therapeutically target PDE function, including enhancing catalytic activity, normalizing altered compartmentalization and modulating post-translational modifications, as well as the potential use of PDEs as disease biomarkers. Importantly, a more refined appreciation of the intramolecular mechanisms regulating PDE function and trafficking is emerging, making these pioneering drug discovery efforts tractable.
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Affiliation(s)
- George S Baillie
- Institute of Cardiovascular and Medical Science, University of Glasgow, Glasgow, UK
| | - Gonzalo S Tejeda
- Institute of Cardiovascular and Medical Science, University of Glasgow, Glasgow, UK
| | - Michy P Kelly
- Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, SC, USA.
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18
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Liu L, Xu H, Ding S, Wang D, Song G, Huang X. Phosphodiesterase 5 inhibitors as novel agents for the treatment of Alzheimer's disease. Brain Res Bull 2019; 153:223-231. [PMID: 31493542 DOI: 10.1016/j.brainresbull.2019.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/18/2019] [Accepted: 09/01/2019] [Indexed: 01/21/2023]
Abstract
Alzheimer's disease (AD), characterized by a progressive impairment of memory and cognition, is a major health problem in both developing and developed countries. Currently, no drugs can reverse the progression of AD. Phosphodiesterase 5 (PDE5) is a critical component of the cyclic guanosine monophosphate/protein kinase G (cGMP/PKG) signaling pathway in neurons, the inhibition of which has produced neuroprotective effects, and PDE5 inhibitors have recently been thought to be potential therapeutic agents for AD. In this paper, we summarized the outstanding progress that has been made in PDE5 inhibitors as anti-AD agents with encouraging results in animal studies, clinical trials and the investigations on the underlying mechanisms. The novel PDE5 inhibitors reported recently in the treatment of AD were also reviewed and discussed.
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Affiliation(s)
- Li Liu
- School of Pharmaceutical Engineering & Life Science, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Huang Xu
- School of Pharmaceutical Engineering & Life Science, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Shumin Ding
- School of Pharmaceutical Engineering & Life Science, Changzhou University, Changzhou, Jiangsu 213164, China
| | - Dongyan Wang
- Department of Medicine, Yangzhou Polytechnic College, Yangzhou, Jiangsu 225009, China
| | - Guoqiang Song
- School of Pharmaceutical Engineering & Life Science, Changzhou University, Changzhou, Jiangsu 213164, China.
| | - Xianfeng Huang
- School of Pharmaceutical Engineering & Life Science, Changzhou University, Changzhou, Jiangsu 213164, China.
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The past and future of novel, non-dopamine-2 receptor therapeutics for schizophrenia: A critical and comprehensive review. J Psychiatr Res 2019; 108:57-83. [PMID: 30055853 DOI: 10.1016/j.jpsychires.2018.07.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 06/13/2018] [Accepted: 07/12/2018] [Indexed: 01/28/2023]
Abstract
Since the discovery of chlorpromazine in the 1950's, antipsychotic drugs have been the cornerstone of treatment of schizophrenia, and all attenuate dopamine transmission at the dopamine-2 receptor. Drug development for schizophrenia since that time has led to improvements in side effects and tolerability, and limited improvements in efficacy, with the exception of clozapine. However, the reasons for clozapine's greater efficacy remain unclear, despite the great efforts and resources invested therewith. We performed a comprehensive review of the literature to determine the fate of previously tested, non-dopamine-2 receptor experimental treatments. Overall we included 250 studies in the review from the period 1970 to 2017 including treatments with glutamatergic, serotonergic, cholinergic, neuropeptidergic, hormone-based, dopaminergic, metabolic, vitamin/naturopathic, histaminergic, infection/inflammation-based, and miscellaneous mechanisms. Despite there being several promising targets, such as allosteric modulation of the NMDA and α7 nicotinic receptors, we cannot confidently state that any of the mechanistically novel experimental treatments covered in this review are definitely effective for the treatment of schizophrenia and ready for clinical use. We discuss potential reasons for the relative lack of progress in developing non-dopamine-2 receptor treatments for schizophrenia and provide recommendations for future efforts pursuing novel drug development for schizophrenia.
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Efficacy of different types of cognitive enhancers for patients with schizophrenia: a meta-analysis. NPJ SCHIZOPHRENIA 2018; 4:22. [PMID: 30361502 PMCID: PMC6202388 DOI: 10.1038/s41537-018-0064-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Revised: 09/13/2018] [Accepted: 09/24/2018] [Indexed: 12/12/2022]
Abstract
Cognitive impairment is a core feature of schizophrenia, which is predictive for functional outcomes and is, therefore, a treatment target in itself. Yet, literature on efficacy of different pharmaco-therapeutic options is inconsistent. This quantitative review provides an overview of studies that investigated potential cognitive enhancers in schizophrenia. We included pharmacological agents, which target different neurotransmitter systems and evaluated their efficacy on overall cognitive functioning and seven separate cognitive domains. In total, 93 studies with 5630 patients were included. Cognitive enhancers, when combined across all different neurotransmitter systems, which act on a large number of different mechanisms, showed a significant (yet small) positive effect size of 0.10 (k = 51, p = 0.023; 95% CI = 0.01 to 0.18) on overall cognition. Cognitive enhancers were not superior to placebo for separate cognitive domains. When analyzing each neurotransmitter system separately, agents acting predominantly on the glutamatergic system showed a small significant effect on overall cognition (k = 29, Hedges’ g = 0.19, p = 0.01), as well as on working memory (k = 20, Hedges’ g = 0.13, p = 0.04). A sub-analysis of cholinesterase inhibitors (ChEI) showed a small effect on working memory (k = 6, Hedges’ g = 0.26, p = 0.03). Other sub-analyses were positively nonsignificant, which may partly be due to the low number of studies we could include per neurotransmitter system. Overall, this meta-analysis showed few favorable effects of cognitive enhancers for patients with schizophrenia, partly due to lack of power. There is a lack of studies involving agents acting on other than glutamatergic and cholinergic systems, especially of those targeting the dopaminergic system.
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Heckman PRA, Blokland A, Bollen EPP, Prickaerts J. Phosphodiesterase inhibition and modulation of corticostriatal and hippocampal circuits: Clinical overview and translational considerations. Neurosci Biobehav Rev 2018; 87:233-254. [PMID: 29454746 DOI: 10.1016/j.neubiorev.2018.02.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 02/07/2018] [Accepted: 02/09/2018] [Indexed: 12/20/2022]
Abstract
The corticostriatal and hippocampal circuits contribute to the neurobiological underpinnings of several neuropsychiatric disorders, including Alzheimer's disease, Parkinson's disease and schizophrenia. Based on biological function, these circuits can be clustered into motor circuits, associative/cognitive circuits and limbic circuits. Together, dysfunctions in these circuits produce the wide range of symptoms observed in related neuropsychiatric disorders. Intracellular signaling in these circuits is largely mediated through the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway with an additional role for the cyclic guanosine monophosphate (cGMP)/ protein kinase G (PKG) pathway, both of which can be regulated by phosphodiesterase inhibitors (PDE inhibitors). Through their effects on cAMP response element-binding protein (CREB) and Dopamine- and cAMP-Regulated PhosphoProtein MR 32 kDa (DARPP-32), cyclic nucleotide pathways are involved in synaptic transmission, neuron excitability, neuroplasticity and neuroprotection. In this clinical review, we provide an overview of the current clinical status, discuss the general mechanism of action of PDE inhibitors in relation to the corticostriatal and hippocampal circuits and consider several translational challenges.
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Affiliation(s)
- P R A Heckman
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands; Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands.
| | - A Blokland
- Department of Neuropsychology and Psychopharmacology, Maastricht University, Maastricht, The Netherlands
| | - E P P Bollen
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - J Prickaerts
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
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Hsu WY, Lane HY, Lin CH. Medications Used for Cognitive Enhancement in Patients With Schizophrenia, Bipolar Disorder, Alzheimer's Disease, and Parkinson's Disease. Front Psychiatry 2018; 9:91. [PMID: 29670547 PMCID: PMC5893641 DOI: 10.3389/fpsyt.2018.00091] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 03/06/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND/AIMS Cognitive impairment, which frequently occurs in patients with schizophrenia, bipolar disorder, Alzheimer's disease, and Parkinson's disease, has a significant impact on the daily lives of both patients and their family. Furthermore, since the medications used for cognitive enhancement have limited efficacy, the issue of cognitive enhancement still remains a clinically unsolved challenge. SAMPLING AND METHODS We reviewed the clinical studies (published between 2007 and 2017) that focused on the efficacy of medications used for enhancing cognition in patients with schizophrenia, bipolar disorder, Alzheimer's disease, and Parkinson's disease. RESULTS Acetylcholinesterase inhibitors and memantine are the standard treatments for Alzheimer's disease and Parkinson's disease. Some studies have reported selective cognitive improvement in patients with schizophrenia following galantamine treatment. Newer antipsychotics, including paliperidone, lurasidone, aripiprazole, ziprasidone, and BL-1020, have also been reported to exert cognitive benefits in patients with schizophrenia. Dopaminergic medications were found to improve language function in patients with Parkinson's disease. However, no beneficial effects on cognitive function were observed with dopamine agonists in patients with schizophrenia. The efficacies of nicotine and its receptor modulators in cognitive improvement remain controversial, with the majority of studies showing that varenicline significantly improved the cognitive function in schizophrenic patients. Several studies have reported that N-methyl-d-aspartate glutamate receptor (NMDAR) enhancers improved the cognitive function in patients with chronic schizophrenia. NMDAR enhancers might also have cognitive benefits in patients with Alzheimer's disease or Parkinson's disease. Raloxifene, a selective estrogen receptor modulator, has also been demonstrated to have beneficial effects on attention, processing speed, and memory in female patients with schizophrenia. CONCLUSION Clinical trials with larger sample sizes evaluating comprehensive cognitive domains are warranted to examine the efficacy of medications in cognitive enhancement in patients with schizophrenia, bipolar disorder, Alzheimer's disease, and Parkinson's disease.
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Affiliation(s)
- Wen-Yu Hsu
- Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan.,Changhua Christian Hospital, Changhua, Taiwan.,School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Hsien-Yuan Lane
- Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan.,Psychiatry, China Medical University and Hospital, Taichung, Taiwan
| | - Chieh-Hsin Lin
- Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan.,Psychiatry, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
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Barone I, Giordano C, Bonofiglio D, Andò S, Catalano S. Phosphodiesterase type 5 and cancers: progress and challenges. Oncotarget 2017; 8:99179-99202. [PMID: 29228762 PMCID: PMC5716802 DOI: 10.18632/oncotarget.21837] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 09/23/2017] [Indexed: 01/05/2023] Open
Abstract
Cancers are an extraordinarily heterogeneous collection of diseases with distinct genetic profiles and biological features that directly influence response patterns to various treatment strategies as well as clinical outcomes. Nevertheless, our growing understanding of cancer cell biology and tumor progression is gradually leading towards rational, tailored medical treatments designed to destroy cancer cells by exploiting the unique cellular pathways that distinguish them from normal healthy counterparts. Recently, inhibition of the activity of phosphodiesterase type 5 (PDE5) is emerging as a promising approach to restore normal intracellular cyclic guanosine monophosphate (cGMP) signalling, and thereby resulting into the activation of various downstream molecules to inhibit proliferation, motility and invasion of certain cancer cells. In this review, we present an overview of the experimental and clinical evidences highlighting the role of PDE5 in the pathogenesis and prevention of various malignancies. Current data are still not sufficient to draw conclusive statements for cancer patient management, but could provide further rational for testing PDE5-targeting drugs as anticancer agents in clinical settings.
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Affiliation(s)
- Ines Barone
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Cinzia Giordano
- Centro Sanitario, University of Calabria, Arcavacata di Rende, CS, Italy
| | - Daniela Bonofiglio
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Sebastiano Andò
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Stefania Catalano
- Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Arcavacata di Rende, Italy
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Prickaerts J, Heckman PRA, Blokland A. Investigational phosphodiesterase inhibitors in phase I and phase II clinical trials for Alzheimer's disease. Expert Opin Investig Drugs 2017; 26:1033-1048. [PMID: 28772081 DOI: 10.1080/13543784.2017.1364360] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Phosphodiesterase (PDE) inhibitors improve signaling pathways in brain circuits by increasing intracellular cyclic adenosine monophosphate (cAMP) and/or cyclic guanosine monophosphate (cGMP). In the last decade, the first clinical studies investigating selective PDE inhibitors in Alzheimer's disease (AD) have been initiated, based on their positive effects on cognitive processes and neuroprotection in numerous animal studies. Areas covered: This article reviews the clinical studies investigating the pro-cognitive/neuroprotective effects of PDE inhibitors in patients with AD, as well as in age-associated memory impaired elderly and patients with mild cognitive impairment (MCI), the prodromal stage of AD. PDE inhibitors will also be discussed with respect to adverse effects including safety and tolerability. Expert opinion: The limited available data of clinical studies with PDE inhibitors tested in different populations of AD patients do not allow the drawing of any concrete conclusion yet. Currently, studies with a PDE3 (cilostazol) or PDE9 inhibitor (BI 409,306) are still ongoing in patients with MCI or AD, respectively. Studies with PDE4 inhibitors (HT-0712, roflumilast and BPN14770) in healthy elderly and elderly with age-associated memory impairments indicate that the optimum dose and/or inhibiting the most relevant PDE isoform hold great promise when tested in the appropriate population of patients with MCI or AD eventually.
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Affiliation(s)
- Jos Prickaerts
- a Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience , Maastricht University , Maastricht , The Netherlands
| | - Pim R A Heckman
- a Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience , Maastricht University , Maastricht , The Netherlands.,b Department of Neuropsychology and Psychopharmacology , Maastricht University , Maastricht , The Netherlands
| | - Arjan Blokland
- b Department of Neuropsychology and Psychopharmacology , Maastricht University , Maastricht , The Netherlands
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Heckman PRA, Blokland A, Prickaerts J. From Age-Related Cognitive Decline to Alzheimer's Disease: A Translational Overview of the Potential Role for Phosphodiesterases. ADVANCES IN NEUROBIOLOGY 2017; 17:135-168. [PMID: 28956332 DOI: 10.1007/978-3-319-58811-7_6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Phosphodiesterase inhibitors (PDE-Is) are pharmacological compounds enhancing cAMP and/or cGMP signaling. Both these substrates affect neural communication by influencing presynaptic neurotransmitter release and postsynaptic intracellular pathways after neurotransmitter binding to its receptor. Both cAMP and cGMP play an important role in a variety of cellular functions including neuroplasticity and neuroprotection. This chapter provides a translational overview of the effects of different classes of PDE-Is on cognition enhancement in age-related cognitive decline and Alzheimer's disease (AD). The most effective PDE-Is in preclinical models of aging and AD appear to be PDE2-Is, PDE4-Is and PDE5-Is. Clinical studies are relatively sparse and so far PDE1-Is and PDE4-Is showed some promising results. In the future, the demonstration of clinical proof of concept and the generation of isoform selective PDE-Is are the hurdles to overcome in developing safe and efficacious novel PDE-Is for the treatment of age-related cognitive decline and cognitive dysfunction in AD.
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Affiliation(s)
- Pim R A Heckman
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, PO Box 616, 6200, MD, Maastricht, The Netherlands
- Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200, MD, Maastricht, The Netherlands
| | - Arjan Blokland
- Department of Neuropsychology and Psychopharmacology, Maastricht University, PO Box 616, 6200, MD, Maastricht, The Netherlands
| | - Jos Prickaerts
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, PO Box 616, 6200, MD, Maastricht, The Netherlands.
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Bacconi L, Gressier F. [Efficacy and tolerance of PDE-5 in the treatment of erectile dysfunction in schizophrenic patients: A literature review]. Encephale 2016; 43:55-61. [PMID: 27658991 DOI: 10.1016/j.encep.2016.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 12/07/2015] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Sexual dysfunction is an important public health problem in men and is associated with reduced quality of life. It is more common in patients with schizophrenia. It is well-established that antipsychotic drugs cause sexual dysfunction with consequences on the quality of life of patients, adherence to treatment, and public health costs. Phosphodiesterase type 5 inhibitors (PDE5 inhibitors) are indicated for the management of erectile dysfunction. However, there is little information on such treatment in schizophrenic patients. This literature review aimed to summarize the current data on the efficacy and tolerability of PDE-5 inhibitors in the erectile dysfunction in schizophrenic patients. MATERIAL AND METHODS PubMed, PsycInfo and Cochrane databases were searched for studies published until August 2014. RESULTS Only 6 studies met the inclusion criteria. Three were randomized, double-blind, cross-over, placebo-controlled trials and three were open studies. Various scales were used to measure erectile and orgasmic function, desire, satisfaction during intercourse, overall satisfaction, quality of life and intensity of schizophrenic symptoms. In the 3 randomized studies (one with sildenafil 25-50 mg, one with lodenafil carbonate 80 mg/j and the last one with tadalafil 10 mg), the rate of participants who completed the trial was high (around 95 %). All three included patients with schizophrenia or schizophrenia spectrum disorders. Patients reported significant improvement on sexual dysfunction. However, no statistical difference was reported between lodenafil and placebo, on different scales, suggesting a very important placebo effect in patients with schizophrenia. All three found a good tolerance of PDE-5 inhibitors. Side effects were rare and were mainly nasal congestion, headaches, nausea and dizziness. There were no major side effects or drug interactions. Considering the 3 open studies, 2 involved sildenafil and one tadalafil. All concluded in improved erectile and orgasmic function, desire, satisfaction during intercourse, overall satisfaction, and even the quality of life when it was studied. However, very few patients were included. DISCUSSION Little data are available on the use of PDE5 inhibitors in schizophrenic patients. The 6 studies included few patients which reduces the power and the scope of their conclusions. There is also an important bias due to the use of self-questionnaires. The methodologies of the studies differ in many aspects which limits the comparability. Inclusion and exclusion criteria, drugs used and scales varied among the studies. However, the management of erectile disorder seems to be a consistent target in an integrative approach for the overall well-being of schizophrenic patients. PDE-5 inhibitors appear to be safe and could improve erectile function in schizophrenic patients. CONCLUSION In total, the current data suggest efficiency and good tolerance of the use of PDE-5 inhibitors in schizophrenic patients with erectile dysfunction. However, further studies focusing on PDE-5 inhibitors are needed to more deeply assess their efficacy and safety in patients with schizophrenia.
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Affiliation(s)
- L Bacconi
- Service de psychiatrie d'adultes, pôle V(e)-VI(e) arr., CHU Sainte-Anne, 1, rue Cabanis, 75014 Paris, France.
| | - F Gressier
- Inserm UMR 1178, université Paris Sud, service de Psychiatrie d'adultes, CHU de Bicêtre, Assistance publique-hôpitaux de Paris, 78, rue du Général-Leclerc, 94275 Le Kremlin-Bicêtre, France
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Abstract
Although there has been more than 50 years of development, there remains a great need for better antipsychotic medications. This article looks at the recent advances in treatment of schizophrenia. New hypotheses have been suggested that may replace or complement the dopamine hypotheses. The article explores the different novel drugs that impact some of the key neurotransmitter systems currently. Phosphodiesterase 10A inhibitors and α-7 neuronal nicotinic acetylcholine receptor modulators constitute the majority. The marketing of these medications eventually may result in change about how schizophrenia is treated.
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An emerging role of cGMP in the treatment of schizophrenia: A review. Schizophr Res 2016; 170:226-31. [PMID: 26706197 DOI: 10.1016/j.schres.2015.11.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 11/12/2015] [Accepted: 11/16/2015] [Indexed: 01/08/2023]
Abstract
Schizophrenia is a progressive psychotic disorder with devastating effects on the broad aspects of human emotion, perception, thought, and psychosocial interactions. Although treatment with antipsychotic drugs, the mainstay in the treatment of schizophrenia, the large number of patients with schizophrenia respond poorly to the pharmacological and, the large number of patients with schizophrenia poorly respond to the pharmacological treatment. Although a variety of novel therapeutics have long been tested, to date, no drugs clinically efficacious for schizophrenia are available. The multiple lines of evidence strongly suggest that the modulation of cyclic guanosine monophosphate (cGMP) is a promising target in promoting the novel therapeutic strategies of schizophrenia beyond the "receptor-dependent" psychopharmacology. cGMP is modulated via regulating its synthesis by N-methyl-d-aspartate receptor (NMDAR) and nitric oxide (NO), which regulate guannylyl cyclase (GC), the enzyme producing cGMP. cGMP is also regulated by phosphodiesterase (PDE), the enzyme hydrolyzing cGMP. In this review, we critically evaluate the therapeutic potential of agents modulating cGMP activity by regulating cGMP synthesis including NMDAR enhancers, NO enhancers, NO inhibitors including minocycline with anti-inflammatory properties and PDE inhibitors in improving the negative, cognitive and positive symptoms of schizophrenia. We also discuss the possible mechanisms by which these agents produce therapeutic effects on schizophrenia including cGMP signaling pathways, oxidative stress, and neuroinflammation.
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Abstract
PURPOSE OF REVIEW The ketamine model has dominated drug discovery in schizophrenia over the past decade, supported by genetic and postmortem evidence implicating glutamatergic transmission. This review assesses recent successes and disappointments of glutamatergic agents and identifies promising new directions. RECENT FINDINGS Strategies focused on enhancing activity of the N-methyl D-aspartate (NMDA) receptor via direct agonists at the glycine site or by inhibition of glycine reuptake have produced modest and often inconsistent evidence of efficacy, as have approaches to reduce excessive glutamate release by lamotrigine or by mGluR2/3 agonists. Strategies targeting α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors have also met with only limited success. Newer approaches include selective allosteric modulation of NMDA receptor subunits and of mGluR5 receptors. In addition, intracellular pathways downstream of NMDA receptors may also provide new treatment targets, as exemplified by phosphodiesterase (PDE) inhibitors. SUMMARY Targeting glutamatergic transmission remains one of the most promising strategies in schizophrenia, particularly early in the course of illness, but therapeutic approaches may require greater specificity for receptor subtype type, illness phase, and individual biology in order to enhance efficacy and overcome problems with reproducibility of clinical results.
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Critical role of nitric oxide in the modulation of prepulse inhibition in Swiss mice. Psychopharmacology (Berl) 2014; 231:663-72. [PMID: 24101156 DOI: 10.1007/s00213-013-3277-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 09/02/2013] [Indexed: 01/13/2023]
Abstract
RATIONALE Nitric oxide (NO) modulates the dopamine uptake and release processes and appears to be implicated in dopamine-related pathologies, such as schizophrenia. However, it is unclear whether there is excess or deficient NO synthesis in schizophrenia pathophysiology. Analyses of the intracellular pathways downstream of NO system activation have identified the cyclic nucleotide cyclic guanosine monophosphate (cGMP) as a possible target for drug development. Defects in the sensorimotor gating of the neural mechanism underlying the integration and processing of sensory information have been detected across species through prepulse inhibition (PPI). OBJECTIVES The aim of this study was to investigate the effects of NO/cGMP increase on sensorimotor gating modulation during dopamine hyperfunction. METHODS Mice were treated with NO donors and subjected to the PPI test. Treatment with the NO donor sodium nitroprusside was preceded by pretreatment with a soluble guanylate cyclase (sGC) inhibitor. Additionally, the mice were treated with NO donors and phosphodiesterases inhibitors prior to amphetamine treatment. RESULTS Pretreatment with the NO donors enhanced the PPI response and attenuated the amphetamine-disruptive effects on the PPI. The sGC inhibitor did not modify the sodium nitroprusside effects. Additionally, the cGMP increase induced by a specific phosphodiesterase inhibitor did not modify the amphetamine-disruptive effect. CONCLUSIONS This study provides the first demonstration that an increase in NO can improve the PPI response and block the amphetamine-disruptive effects on the PPI response. Our data are consistent with recent clinical results. However, these effects do not appear to be related to an increase in cGMP levels, and further investigation is thus required.
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Chue P, Lalonde JK. Addressing the unmet needs of patients with persistent negative symptoms of schizophrenia: emerging pharmacological treatment options. Neuropsychiatr Dis Treat 2014; 10:777-89. [PMID: 24855363 PMCID: PMC4020880 DOI: 10.2147/ndt.s43404] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The negative symptoms of schizophrenia represent an impairment of normal emotional responses, thought processes and behaviors, and include blunting or flattening of affect, alogia/aprosody, avolition/apathy, anhedonia, and asociality. Negative symptoms contribute to a reduced quality of life, increased functional disability, increased burden of illness, and poorer long-term outcomes, to a greater degree than positive symptoms. Primary negative symptoms are prominent and persistent in up to 26% of patients with schizophrenia, and they are estimated to occur in up to 58% of outpatients at any given time. Negative symptoms respond less well to medications than positive symptoms, and to date treatment options for negative symptoms have been limited, with no accepted standard treatment. Modest benefits have been reported with a variety of different agents, including second-generation antipsychotics and add-on therapy with antidepressants and other pharmacological classes. Recent clinical research focusing on negative symptoms target novel biological systems, such as glutamatergic neurotransmission. Different approaches include: enhancing N-methyl-D-aspartate receptor function with agents that bind directly to the glycine ligand site or with glycine reuptake inhibitors; influencing the metabotropic glutamate receptor (mGluR2/3) with positive allosteric modulators; and stimulating nicotinic acetylcholine receptors. In conclusion, the lack of clearly efficacious pharmacological treatments for the management of negative symptoms represents a significant unmet need, especially considering the importance of these symptoms on patient outcomes. Hence, further research to identify and characterize novel pharmacological treatments for negative symptoms is greatly needed.
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Affiliation(s)
- Pierre Chue
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
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32
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Vingerhoets WAM, Bloemen OJN, Bakker G, van Amelsvoort TAMJ. Pharmacological Interventions for the MATRICS Cognitive Domains in Schizophrenia: What's the Evidence? Front Psychiatry 2013; 4:157. [PMID: 24363646 PMCID: PMC3849802 DOI: 10.3389/fpsyt.2013.00157] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 11/16/2013] [Indexed: 01/14/2023] Open
Abstract
Schizophrenia is a disabling, chronic psychiatric disorder with a prevalence rate of 0.5-1% in the general population. Symptoms include positive (e.g., delusions, hallucinations), negative (e.g., blunted affect, social withdrawal), as well as cognitive symptoms (e.g., memory and attention problems). Although 75-85% of patients with schizophrenia report cognitive impairments, the underlying neuropharmacological mechanisms are not well understood and currently no effective treatment is available for these impairments. This has led to the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) initiative, which established seven cognitive domains that are fundamentally impaired in schizophrenia. These domains include verbal learning and memory, visual learning and memory, working memory, attention and vigilance, processing speed, reasoning and problem solving, and social cognition. Recently, a growing number of studies have been conducted trying to identify the underlying neuropharmacological mechanisms of cognitive impairments in schizophrenia patients. Specific cognitive impairments seem to arise from different underlying neuropharmacological mechanisms. However, most review articles describe cognition in general and an overview of the mechanisms involved in these seven separate cognitive domains is currently lacking. Therefore, we reviewed the underlying neuropharmacological mechanisms focusing on the domains as established by the MATRICS initiative which are considered most crucial in schizophrenia.
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Affiliation(s)
- Wilhelmina A M Vingerhoets
- Department of Psychiatry and Psychology, Maastricht University , Maastricht , Netherlands ; Department of Nuclear Medicine, Academic Medical Centre, University of Amsterdam , Amsterdam , Netherlands
| | - Oswald J N Bloemen
- Department of Psychiatry and Psychology, Maastricht University , Maastricht , Netherlands
| | - Geor Bakker
- Department of Psychiatry and Psychology, Maastricht University , Maastricht , Netherlands ; Department of Nuclear Medicine, Academic Medical Centre, University of Amsterdam , Amsterdam , Netherlands
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Effects of daily low-dose treatment with phosphodiesterase type 5 inhibitor on cognition, depression, somatization and erectile function in patients with erectile dysfunction: a double-blind, placebo-controlled study. Int J Impot Res 2013; 26:76-80. [PMID: 24285284 DOI: 10.1038/ijir.2013.38] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 08/29/2013] [Accepted: 10/21/2013] [Indexed: 01/09/2023]
Abstract
Phosphodiesterase type 5 (PDE5) inhibitors have recently been shown to have cognitive-enhancing effects in animal models and in our previous pilot study. To investigate the efficacy of daily low-dose treatment with a PDE5 inhibitor on cognitive function, depression and somatization in patients with erectile dysfunction (ED), 8-week, double-blind, placebo-controlled study enrolled 60 male patients with ED for ≥ 3 months without cognitive impairment. Forty-nine patients completed the study. Patients were randomized to receive either daily low-dose udenafil 50 mg or placebo for 2 months. The International Index of Erectile Function-5 (IIEF-5), the Korean version of the Mini-Mental State Examination (K-MMSE) for general cognitive function and the Seoul Neuropsychological Screening Battery for comprehensive neuropsychological examination, the Physical Health Questionnaire-9 (PHQ-9) for depression and the Physical Health Questionnaire-15 (PHQ-15) for somatization were administered at baseline and at 2 months. The change in the mean IIEF-5 was significantly higher in the udenafil group than the placebo group (6.08 ± 4.72 vs 2.20 ± 3.50, P=0.008). The changes in the PHQ-9 and PHQ-15 were -2.04 ± 3.14 and -2.17 ± 2.87 in the udenafil group, and 1.20 ± 1.63 and 0.56 ± 2.48 in the placebo group (both, P<0.001). The changes in the K-MMSE and Digit Span Forward were 1.25 ± 1.26 and 0.92 ± 1.02 in the udenafil group, and -0.52 ± 1.19 and -0.24 ± 1.13 in the placebo group (both, P<0.001). However, there were no differences in the other neuropsychological tests. Daily dosing with a PDE5 inhibitor seems to improve cognitive function, depression and somatization, as well as erectile function, in patients with ED.
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Reneerkens OAH, Sambeth A, Ramaekers JG, Steinbusch HWM, Blokland A, Prickaerts J. The effects of the phosphodiesterase type 5 inhibitor vardenafil on cognitive performance in healthy adults: a behavioral-electroencephalography study. J Psychopharmacol 2013; 27:600-8. [PMID: 23427190 DOI: 10.1177/0269881113477747] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Phosphodiesterase type 5 inhibitors (PDE5-Is) improve cognitive performance of rodents, but the few human studies investigating their effects did not systematically investigate cognitive effects and the results have been quite contradictory. Therefore, we examined whether the PDE5-I vardenafil improves memory and executive functioning and affect electroencephalography (EEG) in healthy young adults. Participants were selected out of a group of volunteers, based on their performance on a memory screening and they were orally treated with vardenafil (10-20 mg or placebo). Memory and executive functioning were tested while EEG activity was recorded. Additionally, a simple reaction time task and questionnaires addressing various complaints were presented. No prominent effects of vardenafil on cognition were found: participants only made more mistakes on a reaction time task after 20 mg vardenafil. During encoding of words, the P300 was generally smaller after vardenafil treatment. Furthermore, the N400 was larger after vardenafil 10 mg than placebo treatment in a spatial memory task at Fz. Finally, headache and feeling weak were reported more after vardenafil treatment. Vardenafil did not affect cognitive performance of healthy adults and showed only some incidental effects on ERPs. These findings in humans do not corroborate the cognition-enhancing effects of PDE5-Is in healthy animals.
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Affiliation(s)
- O A H Reneerkens
- Department of Psychiatry and Neuropsychology, Maastricht University, Maastricht, the Netherlands
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Keefe RSE, Buchanan RW, Marder SR, Schooler NR, Dugar A, Zivkov M, Stewart M. Clinical trials of potential cognitive-enhancing drugs in schizophrenia: what have we learned so far? Schizophr Bull 2013; 39:417-35. [PMID: 22114098 PMCID: PMC3576170 DOI: 10.1093/schbul/sbr153] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In light of the number of studies conducted to examine the treatment of cognitive impairment associated with schizophrenia (CIAS), we critically reviewed recent CIAS trials. Trials were identified through searches of the website "www.clinicaltrials.gov" using the terms "schizophrenia AND cognition," "schizophrenia AND neurocognition," "schizophrenia AND neurocognitive tests," "schizophrenia AND MATRICS," "schizophrenia AND MCCB," "schizophrenia AND BACS," "schizophrenia AND COGSTATE," and "schizophrenia AND CANTAB" and "first-episode schizophrenia AND cognition." The cutoff date was 20 April 2011. Included trials were conducted in people with schizophrenia, the effects on cognition were either a primary or secondary outcome, and the effect of a pharmacologically active substance was examined. Drug challenge, pharmacokinetic, pharmacodynamic, or prodrome of psychosis studies were excluded. We identified 118 trials, with 62% using an add-on parallel group design. The large majority of completed trials were underpowered to detect moderate effect sizes, had ≤8 weeks duration, and were performed in samples of participants with chronic stable schizophrenia. The ongoing add-on trials are longer, have larger sample sizes (with a number of them being adequately powered to detect moderate effect sizes), and are more likely to use a widely accepted standardized cognitive battery (eg, the MATRICS Consensus Cognitive Battery) and MATRICS guidelines. Ongoing studies performed in subjects with recent onset schizophrenia may help elucidate which subjects are most likely to show an effect in cognition. New insights into the demands of CIAS trial design and methodology may help increase the probability of identifying treatments with beneficial effect on cognitive impairment in schizophrenia.
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Affiliation(s)
- Richard S. E. Keefe
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC,To whom correspondence should be addressed; tel: +1 (919) 684-4306, fax: +1 (919) 684-2632, e-mail:
| | - Robert W. Buchanan
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Stephen R. Marder
- Desert Pacific Mental Illness Research, Education, and Clinical Center, Semel Institute for Neuroscience, University of California, Los Angeles, Los Angeles, CA
| | - Nina R. Schooler
- Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, NY
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Reneerkens OAH, Sambeth A, Van Duinen MA, Blokland A, Steinbusch HWM, Prickaerts J. The PDE5 inhibitor vardenafil does not affect auditory sensory gating in rats and humans. Psychopharmacology (Berl) 2013; 225:303-12. [PMID: 22855271 DOI: 10.1007/s00213-012-2817-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Accepted: 07/16/2012] [Indexed: 12/26/2022]
Abstract
RATIONALE Sensory gating is an adaptive mechanism of the brain to prevent overstimulation. Patients suffering from clinical disorders such as Alzheimer's disease or schizophrenia exhibit a deficit in gating, which indicates not only an impairment in basic information processing that might contribute to the cognitive problems seen in these patients. Phosphodiesterase type 5 inhibitors (PDE5-Is) have been shown to improve cognition in rodents in various behavioural tasks and might consequently be an interesting target for cognition enhancement. However, the effects of PDE5-Is on sensory gating are not known yet. OBJECTIVES This work aims to study the effects of PDE5 inhibition on auditory sensory gating in rats and humans. METHODS In the rat study, vehicle or 0.3-3 mg/kg of the PDE5-I vardenafil was given orally 30 min before testing and electrode locations were the vertex, hippocampus and the striatum. The human subjects received placebo, 10-20 mg vardenafil 85 min before testing and sensory gating was measured at the cortex (Fz, Fcz and Cz) electrodes. RESULTS Significant gating was only found for the N1 component in rats while all three peaks P1, N1 and P2 showed gating in humans, i.e. the response to the second sound click was decreased as compared with the first for these deflections. Administration of vardenafil did neither have an effect on sensory gating in rats nor in humans. CONCLUSIONS These findings imply that positive effects of PDE5 inhibition on cognition are not mediated by more early phases of information processing.
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Affiliation(s)
- O A H Reneerkens
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
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Reneerkens OA, Rutten K, Akkerman S, Blokland A, Shaffer CL, Menniti FS, Steinbusch HW, Prickaerts J. Phosphodiesterase type 5 (PDE5) inhibition improves object recognition memory: Indications for central and peripheral mechanisms. Neurobiol Learn Mem 2012; 97:370-9. [DOI: 10.1016/j.nlm.2012.02.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 02/16/2012] [Accepted: 02/27/2012] [Indexed: 01/10/2023]
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Selective phosphodiesterase inhibitors improve performance on the ED/ID cognitive task in rats. Neuropharmacology 2012; 62:1182-90. [DOI: 10.1016/j.neuropharm.2011.08.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 08/03/2011] [Accepted: 08/04/2011] [Indexed: 12/20/2022]
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Testing of Neurotropic Effects of Viagra. NEUROPHYSIOLOGY+ 2012. [DOI: 10.1007/s11062-012-9241-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Kloner RA, Comstock G, Levine LA, Tiger S, Stecher VJ. Investigational noncardiovascular uses of phosphodiesterase-5 inhibitors. Expert Opin Pharmacother 2011; 12:2297-313. [DOI: 10.1517/14656566.2011.600306] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Shim YS, Pae CU, Kim SW, Kim HW, Kim JC, Koh JS. Effects of repeated dosing with Udenafil (Zydena) on cognition, somatization and erection in patients with erectile dysfunction: a pilot study. Int J Impot Res 2011; 23:109-14. [PMID: 21544084 DOI: 10.1038/ijir.2011.13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The PDE5 inhibitors have recently been found to have cognitive-enhancing effects in animal models. To investigate the efficacy of repeated dosing with a PDE5 inhibitor on cognitive function and somatization in patients with erectile dysfunction, 27 patients with erectile dysfunction received udenafil (100 mg) at 3-day intervals for 2 months. The international index of erectile function-5 (IIEF-5), a cognitive battery (the Korean version of mini-mental state examination (K-MMSE), the frontal assessment battery (K-FAB), the Seoul verbal learning test) and a physical health questionnaire-15 (PHQ-15) were performed at baseline and at 2 months, following the administration of udenafil. The patients were divided on the basis of their IIEF-5 score into responders (change>7) and non-responders. The mean IIEF-5 score was significantly increased after treatment (7.92 ± 3.83 to 16.33 ± 4.75, P<0.001). The scores of K-MMSE (27.03 ± 1.58 to 28.07 ± 1.57, P=0.001), K-FAB (13.65 ± 1.96 to 15.41 ± 1.85, P<0.001) and PHQ-15 (18.92 ± 4.96 to 17.63 ± 4.75, P=0.003) were significantly improved after treatment. In addition, the responders (n=16) had more improved cognitive function (r=0.603, P=0.001) and somatization (r=-0.402, P=0.038) than non-responders (n=11). Repeated dosing with a PDE5 inhibitor seems to improve cognitive function and somatization, as well as erectile function in patients with erectile dysfunction.
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Affiliation(s)
- Y S Shim
- Department of Neurology, The Catholic University of Korea, Bucheon St. Mary's Hospital, Bucheon, Korea
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Author reply. Psychopharmacology (Berl) 2011. [DOI: 10.1007/s00213-010-2156-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Plath N, Lerdrup L, Larsen PH, Redrobe JP. Can small molecules provide truly effective enhancement of cognition? Current achievements and future directions. Expert Opin Investig Drugs 2011; 20:795-811. [PMID: 21510828 DOI: 10.1517/13543784.2011.574612] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION The prevalence of age-related diseases that implicate a deterioration of cognitive abilities is increasing. Moreover, cognitive decline occurs in numerous CNS disorders affecting patients at younger ages as well, resulting in reduced functional ability and quality of life. Despite the existence of few medications treating cognition, the need for efficacious treatment options to alleviate, halt or even prevent cognitive decline is generally unmet to date. Consequently, extensive research efforts are undertaken to identify medications that can effectively enhance cognition. AREAS COVERED This review covers ongoing clinical trials for cognition and reflects on efforts undertaken to increase the success rates of procognitive drug treatment. The review discusses ways to optimize the drug development process for cognition enhancing agents at the preclinical to clinical interface and provides concrete examples. EXPERT OPINION The existing efficacy readouts addressing cognition in preclinical research offer little translational validity to the clinical situation. In order to identify truly efficacious drug candidates, biomarkers need to be developed that directly address conserved mechanisms underlying cognitive performances. To this end, technologies such as neuroimaging or electroencephalography constitute promising entry points for identifying both the cognitive domain and the patient population most responsive to drug treatment.
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Affiliation(s)
- Niels Plath
- Synaptic Transmission, H. Lundbeck A/S, Ottiliavej 9, 2500 Valby, Denmark.
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Wallace TL, Ballard TM, Pouzet B, Riedel WJ, Wettstein JG. Drug targets for cognitive enhancement in neuropsychiatric disorders. Pharmacol Biochem Behav 2011; 99:130-45. [PMID: 21463652 DOI: 10.1016/j.pbb.2011.03.022] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 03/18/2011] [Accepted: 03/28/2011] [Indexed: 12/11/2022]
Abstract
The investigation of novel drug targets for treating cognitive impairments associated with neurological and psychiatric disorders remains a primary focus of study in central nervous system (CNS) research. Many promising new therapies are progressing through preclinical and clinical development, and offer the potential of improved treatment options for neurodegenerative diseases such as Alzheimer's disease (AD) as well as other disorders that have not been particularly well treated to date like the cognitive impairments associated with schizophrenia (CIAS). Among targets under investigation, cholinergic receptors have received much attention with several nicotinic agonists (α7 and α4β2) actively in clinical trials for the treatment of AD, CIAS and attention deficit hyperactivity disorder (ADHD). Both glutamatergic and serotonergic (5-HT) agonists and antagonists have profound effects on neurotransmission and improve cognitive function in preclinical experiments with animals; some of these compounds are now in proof-of-concept studies in humans. Several histamine H3 receptor antagonists are in clinical development not only for cognitive enhancement, but also for the treatment of narcolepsy and cognitive deficits due to sleep deprivation because of their expression in brain sleep centers. Compounds that dampen inhibitory tone (e.g., GABA(A) α5 inverse agonists) or elevate excitatory tone (e.g., glycine transporter inhibitors) offer novel approaches for treating diseases such as schizophrenia, AD and Down syndrome. In addition to cell surface receptors, intracellular drug targets such as the phosphodiesterases (PDEs) are known to impact signaling pathways that affect long-term memory formation and working memory. Overall, there is a genuine need to treat cognitive deficits associated with many neuropsychiatric conditions as well as an increasingly aging population.
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MESH Headings
- Animals
- Cognition Disorders/drug therapy
- Cognition Disorders/physiopathology
- Glycine Plasma Membrane Transport Proteins/drug effects
- Glycine Plasma Membrane Transport Proteins/physiology
- Humans
- Learning/drug effects
- Learning/physiology
- Memory/drug effects
- Memory/physiology
- Nootropic Agents/pharmacology
- Phosphodiesterase Inhibitors/pharmacology
- Receptors, Cholinergic/drug effects
- Receptors, Cholinergic/physiology
- Receptors, Dopamine/drug effects
- Receptors, Dopamine/physiology
- Receptors, GABA/drug effects
- Receptors, GABA/physiology
- Receptors, Glutamate/drug effects
- Receptors, Glutamate/physiology
- Receptors, Histamine/drug effects
- Receptors, Histamine/physiology
- Receptors, Serotonin/drug effects
- Receptors, Serotonin/physiology
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Affiliation(s)
- Tanya L Wallace
- Center for Neuroscience, SRI International, Menlo Park, CA, USA
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Akhondzadeh S, Ghayyoumi R, Rezaei F, Salehi B, Modabbernia AH, Maroufi A, Esfandiari GR, Naderi M, Ghebleh F, Tabrizi M, Rezazadeh SA. Sildenafil adjunctive therapy to risperidone in the treatment of the negative symptoms of schizophrenia: a double-blind randomized placebo-controlled trial. Psychopharmacology (Berl) 2011; 213:809-15. [PMID: 20949350 DOI: 10.1007/s00213-010-2044-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Accepted: 09/28/2010] [Indexed: 01/22/2023]
Abstract
RATIONAL It has been suggested that phosphodiesterase 5 inhibitors such as sildenafil may be effective in the treatment of negative symptoms of schizophrenia. OBJECTIVE This study was designed to investigate the effect of sildenafil added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double-blind and randomized clinical trial. METHODS Eligible participants in the study were 40 patients with chronic schizophrenia with ages ranging from 18 to 45 years. All patients were inpatients and were in the active phase of the illness and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion: 20 to risperidone (6 mg/day) plus sildenafil (75 mg/day) and 20 to risperidone (6 mg/day) plus placebo. The principal measure of outcome was Positive and Negative Syndrome Scale (PANSS). RESULTS Although both protocols significantly decreased the score of the positive, negative, and general psychopathological symptoms over the trial period, the combination of risperidone and sildenafil showed a significant superiority over risperidone alone in decreasing negative symptoms and PANSS total scores over the 8-week trial (between-subjects factor; F = 4.77, df = 1; P = 0.03; F = 5.91, df = 1, P = 0.02 respectively). CONCLUSION Therapy with 75 mg/day of sildenafil was well tolerated, and no clinically important side effects were observed. The present study indicates sildenafil as a potential adjunctive treatment strategy for treatment of negative symptoms of schizophrenia. This trial is registered with the Iranian Clinical Trials Registry (IRCT1138901151556N11).
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Affiliation(s)
- Shahin Akhondzadeh
- Psychiatric Research Center, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, South Kargar Street, Tehran 13337, Iran.
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Information processing deficits and nitric oxide signalling in the phencyclidine model of schizophrenia. Psychopharmacology (Berl) 2010; 212:643-51. [PMID: 20802999 DOI: 10.1007/s00213-010-1992-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 08/04/2010] [Indexed: 12/22/2022]
Abstract
RATIONALE Schizophrenia-like cognitive deficits induced by phencyclidine (PCP), a drug commonly used to model schizophrenia in experimental animals, are attenuated by nitric oxide (NO) synthase inhibitors. Furthermore, PCP increases NO levels and sGC/cGMP signalling in the prefrontal cortex in rodents. Hence, a cortical NO/sGC/cGMP signalling pathway may constitute a target for novel pharmacological therapies in schizophrenia. OBJECTIVES The objective of this study was to further investigate the role of NO signalling for a PCP-induced deficit in pre-attentive information processing. MATERIALS AND METHODS Male Sprague-Dawley rats were surgically implanted with NO-selective amperometric microsensors aimed at the prefrontal cortex, ventral hippocampus or nucleus accumbens, and NO levels and prepulse inhibition (PPI) were simultaneously assessed. RESULTS PCP treatment increased NO levels in the prefrontal cortex and ventral hippocampus, but not in the nucleus accumbens. The increase in NO levels was not temporally correlated to the deficit in PPI induced by PCP. Furthermore, pretreatment with the neuronal NO synthase inhibitor N-propyl-L-arginine dose-dependently attenuated both the increase in prefrontal cortex NO levels and the deficit in PPI. CONCLUSIONS These findings support a demonstrated role of NO in the behavioural and neurochemical effects of PCP. Furthermore, this effect is brain region-specific and mainly involves the neuronal isoform of NOS. However, a temporal correlation between a PCP-induced disruption of PPI and an increase in prefrontal cortex NO levels was not demonstrated, suggesting that the interaction between PCP and the NO system is more complex than previously thought.
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Goff DC, Hill M, Barch D. The treatment of cognitive impairment in schizophrenia. Pharmacol Biochem Behav 2010; 99:245-53. [PMID: 21115035 DOI: 10.1016/j.pbb.2010.11.009] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 11/05/2010] [Accepted: 11/12/2010] [Indexed: 01/08/2023]
Abstract
Cognitive deficits are major contributors to disability in schizophrenia. Many pharmacologic targets have been identified for cognitive enhancing agents, including receptors involved in dopaminergic, glutamatergic, GABAergic, serotonergic and cholinergic neurotransmission. In addition, new approaches to drug development have been directed towards neuroprotection and the facilitation of neuroplasticity. While several pharmacologic agents and cognitive remediation have shown promise in early trials, no treatment has yet demonstrated efficacy in large replication trials. The experience with different pharmacologic targets is reviewed and methodologic issues are discussed with recommendations for future research.
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Affiliation(s)
- Donald C Goff
- The Schizophrenia Program, Massachusetts General Hospital and Harvard Medical School, USA.
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Barch DM. Pharmacological strategies for enhancing cognition in schizophrenia. Curr Top Behav Neurosci 2010; 4:43-96. [PMID: 21312397 DOI: 10.1007/7854_2010_39] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Researchers have long recognized that individuals with schizophrenia experience challenges in a wide range of cognitive domains, and research on cognitive impairment in schizophrenia is not a recent phenomena. However, the past 10-20 years have seen an increasing recognition of the central importance of cognition to understanding function and outcome in this illness (Green et al. in Schizophr Bull 26:119-136, 2000), an awareness that has shifted the emphasis of at least some work on schizophrenia. More specifically, there has been a rapidly growing body of work on methods of enhancing cognition in schizophrenia, as a means to potentially facilitate improved outcome and quality of life for individuals with this debilitating illness. The current chapter reviews the results of a range of studies examining adjunctive pharmacological treatments to enhance cognition in schizophrenia using a range of designs, including single-dose studies, open-label repeated dosing studies, and double-blind parallel group and crossover designs with repeated dosing. Although many of the single-dose and open-label studies have suggested positive cognitive effects from a range of agents, few of the larger-scale double-blind studies have generated positive results. The current state of results may reflect the need to identify alternative molecular mechanisms for enhancing cognition in schizophrenia or the need to reconceptualize the ways in which pharmacological agents may improve cognition in this illness, with a concomitant change in the traditional clinical trial study design used in prior studies of cognitive enhancement in schizophrenia.
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Affiliation(s)
- Deanna M Barch
- Washington University, St. Louis, One Brookings Drive, Box 1125, St. Louis, MO 63130, USA.
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Bales KR, Plath N, Svenstrup N, Menniti FS. Phosphodiesterase Inhibition to Target the Synaptic Dysfunction in Alzheimer’s Disease. TOPICS IN MEDICINAL CHEMISTRY 2010. [DOI: 10.1007/7355_2010_8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Lakhan SE, Vieira KF. Schizophrenia pathophysiology: are we any closer to a complete model? Ann Gen Psychiatry 2009; 8:12. [PMID: 19445674 PMCID: PMC2689221 DOI: 10.1186/1744-859x-8-12] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Accepted: 05/15/2009] [Indexed: 01/13/2023] Open
Abstract
Schizophrenia, a severe brain disorder that involves hallucinations, disordered thinking and deficiencies in cognition, has been studied for decades in order to determine the early events that lead to this neurological disorder. In this review, we interpret the developmental and genetic models that have been proposed and treatment options associated with these models. Schizophrenia was initially thought to be hereditary based on studies of high incidence in certain families. Additionally, studies on specific genes such as ZDHHC8 and DTNBP1 seem to suggest susceptibility to the onset of this disorder. However, no single gene variation has been linked to schizophrenia, and recent evidence on sporadic cases of schizophrenia refutes genetics as being a singular cause of the disease. In addition, current data suggests neurodevelopmental or environmental causes such as viral infections and prenatal/perinatal complications. Before any brain disorder can be understood, however, multiple cognitive neuroscientific models that accommodate evidence from many biomedical research fields should be considered, and unfortunately, many of these models are in the earliest stages of development. Consequently, it makes us question whether we are any closer to an adequate understanding of the pathophysiology of schizophrenia.
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Affiliation(s)
- Shaheen E Lakhan
- Global Neuroscience Initiative Foundation, Los Angeles, California, USA.
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