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Gouhie FA, Barbosa KO, Cruz ABR, Wellichan MM, Zampolli TM. Cognitive effects of piracetam in adults with memory impairment: A systematic review and meta-analysis. Clin Neurol Neurosurg 2024; 243:108358. [PMID: 38878641 DOI: 10.1016/j.clineuro.2024.108358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 05/20/2024] [Accepted: 05/26/2024] [Indexed: 07/14/2024]
Abstract
INTRODUCTION Piracetam, a widely recognized nootropic drug, is hypothesized to enhance memory function through its influence on synaptic plasticity and neurotransmitter levels. However, despite its popularity, there remains a lack of conclusive evidence regarding its impact on memory. Therefore, the present study aims to explore the effects of piracetam on memory in individuals with impaired cognitive function, comparing it to a placebo control group. OBJECTIVES This study will evaluate how piracetam affects memory function, compared to placebo in adults with impairment in this area. METHODS We carried out bibliographical research and meta-analysis of scientific clinical trials comparing memory function in people taking piracetam with those in the placebo group. The PubMed, Dimensions, Embase, and Cochrane Library databases were used. Statistical analysis was performed in R Studio version 4.3.1. RESULTS In our analysis, 199 articles were identified, of which we included eighteen studies, comprising a total of 886 patients, of which Piracetam was the treatment option in 442 (49.88 %) patients. Memory enhancement (SMD 0.75; 95 % CI [-0.19; 1.69]; p=0.12; I²=96 %) had no clinical difference between the intervention and the control group. CONCLUSION Upon the conclusion of this study, it is apparent that we cannot definitively ascertain the impact of piracetam on memory function. Further research is warranted to provide a clearer understanding of the cognitive effects of piracetam in individuals with memory impairment. This investigation serves as a significant contribution to the ongoing quest to elucidate the potential benefits of piracetam in the field of cognitive neuroscience.
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Affiliation(s)
- Felipe Araujo Gouhie
- Faculty of Medicine, Federal University of Uberlândia (UFU), Uberlândia, Minas Gerais, Brazil.
| | - Karina Oliveira Barbosa
- Faculty of Medicine, Federal University of Uberlândia (UFU), Uberlândia, Minas Gerais, Brazil
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Chayrov R, Volkova T, Perlovich G, Zeng L, Li Z, Štícha M, Liu R, Stankova I. Synthesis, Neuroprotective Effect and Physicochemical Studies of Novel Peptide and Nootropic Analogues of Alzheimer Disease Drug. Pharmaceuticals (Basel) 2022; 15:ph15091108. [PMID: 36145329 PMCID: PMC9500833 DOI: 10.3390/ph15091108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/20/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022] Open
Abstract
Glutamate is an excitatory neurotransmitter in the nervous system. Excessive glutamate transmission can lead to increased calcium ion expression, related to increased neurotoxicity. Memantine is used for treating patients with Alzheimer’s disease (AD) due to its protective action on the neurons against toxicity caused by over activation of N-methyl-D-aspartate receptors. Nootropics, also called “smart drugs”, are used for the treatment of cognitive deficits. In this work, we evaluate the neuroprotective action of four memantine analogues of glycine derivatives, including glycyl-glycine, glycyl-glycyl-glycine, sarcosine, dimethylglycine and three conjugates with nootropics, modafinil, piracetam and picamilon. The new structural memantine derivatives improved cell viability against copper-induced neurotoxicity in APPswe cells and glutamate-induced neurotoxicity in SH-SY5Y cells. Among these novel compounds, modafinil-memantine, piracetam-memantine, sarcosine-memantine, dimethylglycine-memantine, and glycyl-glycine-memantine were demonstrated with good EC50 values of the protective effects on APPswe cells, accompanied with moderate amelioration from glutamate-induced neurotoxicity. In conclusion, our study demonstrated that novel structural derivatives of memantine might have the potential to develop promising lead compounds for the treatment of AD. The solubility of memantine analogues with nootropics and memantine analogues with glycine derivatives in buffer solutions at pH 2.0 and pH 7.4 simulating the biological media at 298.15 K was determined and the mutual influence of the structural fragments in the molecules on the solubility behavior was analyzed. The significative correlation equations relating the solubility and biological properties with the structural HYBOT (Hydrogen Bond Thermodynamics) descriptors were derived. These equations would greatly simplify the task of the directed design of the memantine analogues with improved solubility and enhanced bioavailability.
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Affiliation(s)
- Radoslav Chayrov
- Department of Chemistry, Faculty of Mathematics & Natural Sciences, South-West University “Neofit Rilski”, 2700 Blagoevgrad, Bulgaria
| | - Tatyana Volkova
- G.A. Krestov Institute of Solution Chemistry, Russian Academy of Sciences, 153045 Ivanovo, Russia
| | - German Perlovich
- G.A. Krestov Institute of Solution Chemistry, Russian Academy of Sciences, 153045 Ivanovo, Russia
| | - Li Zeng
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Zhuorong Li
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Martin Štícha
- Faculty of Science, Charles University in Prague, 128 43 Prague, Czech Republic
| | - Rui Liu
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
- Correspondence: (R.L.); (I.S.); Tel.: +86-10-67087731 (R.L.); +359-897-295919 (I.S.)
| | - Ivanka Stankova
- Department of Chemistry, Faculty of Mathematics & Natural Sciences, South-West University “Neofit Rilski”, 2700 Blagoevgrad, Bulgaria
- Correspondence: (R.L.); (I.S.); Tel.: +86-10-67087731 (R.L.); +359-897-295919 (I.S.)
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Malík M, Tlustoš P. Nootropics as Cognitive Enhancers: Types, Dosage and Side Effects of Smart Drugs. Nutrients 2022; 14:3367. [PMID: 36014874 PMCID: PMC9415189 DOI: 10.3390/nu14163367] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 12/22/2022] Open
Abstract
Nootropics, also known as "smart drugs" are a diverse group of medicinal substances whose action improves human thinking, learning, and memory, especially in cases where these functions are impaired. This review provides an up-to-date overview of the potential effectiveness and importance of nootropics. Based on their nature and their effects, this heterogeneous group of drugs has been divided into four subgroups: classical nootropic compounds, substances increasing brain metabolism, cholinergic, and plants and their extracts with nootropic effects. Each subgroup of nootropics contains several main representatives, and for each one, its uses, indications, experimental treatments, dosage, and possible side effects and contraindications are discussed. For the nootropic plant extracts, there is also a brief description of each plant representative, its occurrence, history, and chemical composition of the medicinal part. Lastly, specific recommendations regarding the use of nootropics by both ill and healthy individuals are summarized.
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Affiliation(s)
| | - Pavel Tlustoš
- Department of Agroenvironmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Prague, Czech Republic
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Lin CC, Ondo WG. Non-VMAT2 inhibitor treatments for the treatment of tardive dyskinesia. J Neurol Sci 2018; 389:48-54. [PMID: 29433806 DOI: 10.1016/j.jns.2018.02.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 02/02/2018] [Indexed: 02/05/2023]
Abstract
Although VMAT2-inhibitors are now established as first-line treatment for tardive dyskinesia, not all patients respond to, or tolerate them. Numerous other agents have been adopted to treat tardive dyskinesia, but with variable results and generally lower quality methodologic reports. Amantadine is the most promising but benzodiazepines, branched chain neutral amino acids, Vitamin B6, several nutraceuticals, and botulinum toxin injections might help some patients. In all cases, better placebo controlled trials are needed before definitive recommendations can be made.
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Affiliation(s)
| | - William G Ondo
- Methodist Neurological Institute, Houston, TX, USA; Weill Cornell Medical School, New York, NY, USA.
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Gromova OA, Torshin IY, Kalacheva AG, Fedotova LE, Rudakov KV. [Molecular mechanisms of pidolate magnesium action and its neurotropic affects]. Zh Nevrol Psikhiatr Im S S Korsakova 2017; 116:96-103. [PMID: 28139633 DOI: 10.17116/jnevro201611612196-103] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIM A complex study of pharmacological properties of magnesium pyroglutamate using the modern methods of chemoinformatics and bioinformatics. MATERIAL AND METHODS Pharmacological properties of magnesium pyroglutamate were studied using chemoinformatic and bioinformatic analyses. RESULTS Neurotropic effects of magnesium pyroglutamate are due to an influence on the synthesis of neuropeptides containing pyroglutamate (orexin, thyroliberin, neurotensin etc) and due to the similarity between pyroglutamate-anion with some neuroactive components (L-theanine, 2-pirrolydinone, piracetam). CONCLUSION The results of the study suggest neuroprotective, sedative and antidepressive properties of magnesium pyroglutamate which are realized by pyroglutamate-anion in the synergism with magnesium cation.
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Affiliation(s)
- O A Gromova
- Ivanovo State Medical Academy, Ivanovo, Russia
| | - I Yu Torshin
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | | | | | - K V Rudakov
- Ivanovo State Medical Academy, Ivanovo, Russia, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
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Mendes GD, Zaffalon GT, Silveira AS, Ramacciato JC, Motta RHL, Gagliano-Jucá T, Lopes AG, de Almeida Magalhães JC, De Nucci G. Assessment of pharmacokinetic interaction between piracetam and l-carnitine in healthy subjects. Biomed Chromatogr 2015; 30:536-42. [PMID: 26248695 DOI: 10.1002/bmc.3579] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/11/2015] [Accepted: 08/03/2015] [Indexed: 11/07/2022]
Abstract
A rapid, sensitive and specific method for quantifying piracetam in human plasma using Piracetam d-8 as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by one-step precipitation of protein using an acetonitrile (100%). The extracts were analyzed by high-performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-MS/MS). The method had a chromatographic run time of 3.8 min and a linear calibration curve over the range 0.5-50 µg/mL (r > 0.99). This LC-MS-MS procedure was used to assess the bioavailability of two piracetam formulations: piracetam + l-carnitine (Piracar®; 270/330 mg tablet) and piracetam (Nootropil®; 800 mg tablet) in healthy volunteers of both sexes. The geometric means with corresponding 90% confidence interval (CI) for test/reference percentage ratios were 88.49% (90% CI = 81.19 - 96.46) for peak concentration/dose and 102.55% (90% CI = 100.62 - 104.51) for AUCinf /dose. The limit of quantitation of 0.5 µg/mL is well suited for pharmacokinetic studies in healthy volunteers. It was concluded that piracetam (Piracar®; 270/330 mg tablet) has a bioavailability equivalent to the piracetam (Nootropil®; 800 mg tablet) formulation with regard to both the rate and the extent of absorption.
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Affiliation(s)
- Gustavo D Mendes
- Department of Pharmacology, University Camilo Castelo Branco, SP, Brazil.,Galeno Research Unit, Latino Coelho St, 1301, Parque Taquaral, 13087-010, Campinas, SP, Brazil
| | - Gabriela Traldi Zaffalon
- Department of Pharmacology, University Camilo Castelo Branco, SP, Brazil.,Faculty of Odontology, Dental Research Center São Leopoldo Mandic, Campinas, SP, Brazil
| | - Antonio Sérgio Silveira
- Galeno Research Unit, Latino Coelho St, 1301, Parque Taquaral, 13087-010, Campinas, SP, Brazil
| | | | | | - Thiago Gagliano-Jucá
- Galeno Research Unit, Latino Coelho St, 1301, Parque Taquaral, 13087-010, Campinas, SP, Brazil
| | - Anibal Gil Lopes
- Department of Physiology, Faculty of Medicine, University Camilo Castelo Branco, SP, Brazil
| | | | - Gilberto De Nucci
- Department of Pharmacology, University Camilo Castelo Branco, SP, Brazil.,Department of Pharmacology, University of Sao Paulo, São Paulo, SP, Brazil
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Kale PP, Addepalli V, Sarkar A, Patel S, Savai J. The Combination of Antidepressant Duloxetine with Piracetam in Mice does not Produce Enhancement of Nootropic Activity. Exp Neurobiol 2014; 23:224-30. [PMID: 25258569 PMCID: PMC4174613 DOI: 10.5607/en.2014.23.3.224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 08/27/2014] [Accepted: 08/27/2014] [Indexed: 01/11/2023] Open
Abstract
There is a strong association between depression and memory impairment. The present study aims to assess the nootropic activity of duloxetine and piracetam combination. Male Swiss Albino mice were divided randomly into 4 groups. Treatment of normal saline (10 ml/kg), duloxetine (10 mg/kg), piracetam (100 mg/kg), and duloxetine (5 mg/kg) plus piracetam (50 mg/kg) were given through intra-peritoneal route to group I-IV, respectively. Transfer latency in elevated plus maze (EPM) and time spent in target quadrant in Morris water maze (MWM) were recorded. Estimation of brain monoamines in hippocampus, cerebral cortex, and whole brain were done using HPLC with fluorescence detector. Piracetam treated group showed significant decrease in transfer latency in EPM and increase in time spent in target quadrant recorded in MWM. Combination treated group failed to produce statistically significant nootropic effect in both EPM and MWM. Combination treated group failed to increase brain monoamine levels when compared against duloxetine and piracetam treated groups, separately. But there was exception of significant increase in norepinephrine levels in hippocampi when compared against duloxetine treated group. Results indicate no cognitive benefits with piracetam plus duloxetine combination. These findings can be further probed with the aim of understanding the interaction between duloxetine and piracetam as a future endeavor.
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Affiliation(s)
- Pravin Popatrao Kale
- Department of Pharmacology, SPP SPTM, NMIMS University, India. ; Department of Pharmacology, Dr. Bhanuben Nanavati College of Pharmacy, Mumbai 400-056, India
| | | | - Amrita Sarkar
- Department of Pharmacology, SPP SPTM, NMIMS University, India
| | - Sonam Patel
- Department of Pharmacology, SPP SPTM, NMIMS University, India
| | - Jay Savai
- Department of Pharmacology, SPP SPTM, NMIMS University, India
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8
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Colucci L, Bosco M, Rosario Ziello A, Rea R, Amenta F, Fasanaro AM. Effectiveness of nootropic drugs with cholinergic activity in treatment of cognitive deficit: a review. J Exp Pharmacol 2012; 4:163-72. [PMID: 27186129 PMCID: PMC4863555 DOI: 10.2147/jep.s35326] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Nootropics represent probably the first “smart drugs” used for the treatment of cognitive deficits. The aim of this paper is to verify, by a systematic analysis of the literature, the effectiveness of nootropics in this indication. The analysis was limited to nootropics with cholinergic activity, in view of the role played by acetylcholine in learning and memory. Acetylcholine was the first neurotransmitter identified in the history of neuroscience and is the main neurotransmitter of the peripheral, autonomic, and enteric nervous systems. We conducted a systematic review of the literature for the 5-year period 2006–2011. From the data reported in the literature, it emerges that nootropics may be an effective alternative for strengthening and enhancing cognitive performance in patients with a range of pathologies. Although nootropics, and specifically the cholinergic precursors, already have a long history behind them, according to recent renewal of interest, they still seem to have a significant therapeutic role. Drugs with regulatory indications for symptomatic treatment of Alzheimer’s disease, such as cholinesterase inhibitors and memantine, often have transient effects in dementia disorders. Nootropics with a cholinergic profile and documented clinical effectiveness in combination with cognate drugs such as cholinesterase inhibitors or alone in patients who are not suitable for these inhibitors should be taken into account and evaluated further.
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Affiliation(s)
- Luisa Colucci
- Centro di Ricerche Cliniche, Telemedicina e Telefarmacia, Università di Camerino, Camerino, Italy; Unità Valutazione Alzheimer, Naples, Italy
| | | | - Antonio Rosario Ziello
- Centro di Ricerche Cliniche, Telemedicina e Telefarmacia, Università di Camerino, Camerino, Italy; Unità Valutazione Alzheimer, Naples, Italy
| | - Raffaele Rea
- Centro di Ricerche Cliniche, Telemedicina e Telefarmacia, Università di Camerino, Camerino, Italy; Unità Valutazione Alzheimer, Naples, Italy
| | - Francesco Amenta
- Centro di Ricerche Cliniche, Telemedicina e Telefarmacia, Università di Camerino, Camerino, Italy
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Abdel-Salam OME, Khadrawy YA, Salem NA, Sleem AA. Oxidative Stress in a Model of Toxic Demyelination in Rat Brain: The Effect of Piracetam and Vinpocetine. Neurochem Res 2011; 36:1062-72. [DOI: 10.1007/s11064-011-0450-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2011] [Indexed: 12/23/2022]
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Pellerin L, Magistretti PJ. Ampakine CX546 bolsters energetic response of astrocytes: a novel target for cognitive-enhancing drugs acting as alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor modulators. J Neurochem 2005; 92:668-77. [PMID: 15659236 DOI: 10.1111/j.1471-4159.2004.02905.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glutamate was previously shown to enhance aerobic glycolysis i.e. increase glucose utilization and lactate production with no change in oxygen levels, in mouse cortical astrocytes by a mechanism involving glutamate uptake. It is reported here that a similar response is produced in both hippocampal and cerebellar astrocytes. Application of the cognitive-enhancing drug CX546 promoted further enhancement of glucose utilization by astrocytes from each brain area following glutamate exposure. alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors represent the purported molecular target of cognitive-enhancing drugs such as CX546, and the presence of AMPA receptor subunits GluR1-4 was evidenced in astrocytes from all three regions by immunocytochemistry. AMPA itself did not stimulate aerobic glycolysis, but in the presence of CX546, a strong enhancement of glucose utilization and lactate production was obtained in cortical, hippocampal and cerebellar astrocytes. The effect of CX546 was concentration-dependent, with an EC(50) of 93.2 microm in cortical astrocytes. AMPA-induced glucose utilization in the presence of CX546 was prevented by the AMPA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and the negative modulator GYKI 52466. In addition, the metabolic effect of CX546 in the presence of AMPA was mimicked by the AMPA receptor modulator cyclothiazide. Our data suggest that astrocyte energetics represents a novel target for cognitive-enhancing drugs acting as AMPA receptor modulators.
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Affiliation(s)
- Luc Pellerin
- Department of Physiology, University of Lausanne, 7 rue du Bugnon, 1005 Lausanne, Switzerland.
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Brandão F, Paula-Barbosa MM, Cadete-Leite A. Piracetam impedes hippocampal neuronal loss during withdrawal after chronic alcohol intake. Alcohol 1995; 12:279-88. [PMID: 7639963 DOI: 10.1016/0741-8329(94)00107-o] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In previous studies we have demonstrated that prolonged ethanol consumption induced hippocampal neuronal loss. In addition, we have shown that withdrawal after chronic alcohol intake augmented such degenerative activity leading to increased neuronal death in all subregions of the hippocampal formation but in the CA3 field. In an attempt to reverse this situation, we tested, during the withdrawal period, the effects of piracetam (2-oxo-1-pyrrolidine acetamide), a cyclic derivative of gamma-aminobutyric acid, as there is previous evidence that it might act as a neuronoprotective agent. The total number of dentate granule, hilar, and CA3 and CA1 pyramidal cells of the hippocampal formation were estimated using unbiased stereological methods. We found out that in animals treated with piracetam the numbers of dentate granule, hilar, and CA1 pyramidal cells were significantly higher than in pure withdrawn animals, and did not differ from those of alcohol-treated rats that did not undergo withdrawal. These data suggest that piracetam treatment impedes, during withdrawal, the pursuing of neuronal degeneration.
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Affiliation(s)
- F Brandão
- Department of Anatomy, Porto Medical School, Portugal
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Stancheva SL, Alova LG. Biogenic monoamine uptake by rat brain synaptosomes during aging. Effects of nootropic drugs. GENERAL PHARMACOLOGY 1994; 25:981-7. [PMID: 7835648 DOI: 10.1016/0306-3623(94)90107-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
1. In experiments on young (3-5-month-old), adult (10-11-month-old) and old (21-22-month-old) rats, it was found that significant age-related changes occurred in the high-affinity uptake of dopamine (DA), noradrenaline (NA) and serotonin (5-HT) by cortical and striatal synaptosomes. 2. Changes in DA, NA and 5-HT uptake during aging are suggested to be neurochemical correlates of cognition and memory deficits that develops in senescence. 3. The in vitro effects of the nootropic drugs piracetam, aniracetam, meclofenoxate and adafenoxate on the DA, NA and 5-HT uptake by cortical and striatal synaptosomes from young rats were studied. Administered in increasing concentrations (1 x 10(-4) to 5 x 10(-3) M) these drugs inhibited monoamine uptake. 4. Adafenoxate proved to be a more potent monoamine uptake inhibitor than the other three drugs; it inhibited the uptake in the frontal cortex and striatum without selectivity for either monoaminergic system. It is suggested that adafenoxate affects cognition through the involvement of central neurotransmission and particularly through the inhibition of monoamine uptake systems.
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Affiliation(s)
- S L Stancheva
- Department of Experimental Pharmacology, Bulgarian Academy of Sciences, Sofia
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Gouliaev AH, Senning A. Piracetam and other structurally related nootropics. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1994; 19:180-222. [PMID: 8061686 DOI: 10.1016/0165-0173(94)90011-6] [Citation(s) in RCA: 247] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Nearly three decades have now passed since the discovery of the piracetam-like nootropics, compounds which exhibit cognition-enhancing properties, but for which no commonly accepted mechanism of action has been established. This review covers clinical, pharmacokinetic, biochemical and behavioural results presented in the literature from 1965 through 1992 (407 references) of piracetam, oxiracetam, pramiracetam, etiracetam, nefiracetam, aniracetam and rolziracetam and their structural analogues. The piracetam-like nootropics are capable of achieving reversal of amnesia induced by, e.g., scopolamine, electroconvulsive shock and hypoxia. Protection against barbiturate intoxication is observed and some benefit in clinical studies with patients suffering from mild to moderate degrees of dementia has been demonstrated. No affinity for the alpha 1-, alpha 2-, beta-, muscarinic, 5-hydroxytryptamine-, dopamine, adenosine-A1-, mu-opiate, gamma-aminobutyric acid (GABA) (except for nefiracetam (GABAA)), benzodiazepine and glutamate receptors has been found. The racetams possess a very low toxicity and lack serious side effects. Increased turnover of different neurotransmitters has been observed as well as other biochemical findings, e.g., inhibition of enzymes such as prolylendopeptidase. So far, no generally accepted mechanism of action has, however, emerged. We believe that the effect of the racetams is due to a potentiation of already present neurotransmission and that much evidence points in the direction of a modulated ion flux by, e.g., potentiated calcium influx through non-L-type voltage-dependent calcium channels, potentiated sodium influx through alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor gated channels or voltage-dependent channels or decreases in potassium efflux. Effects on carrier mediated ion transport are also possible.
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Affiliation(s)
- A H Gouliaev
- Department of Chemistry, Aarhus University, Denmark
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Mondadori C. In search of the mechanism of action of the nootropics: new insights and potential clinical implications. Life Sci 1994; 55:2171-8. [PMID: 7997076 DOI: 10.1016/0024-3205(94)00398-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The positive action of nootropics on the memory has up to now primarily been discussed in the context of effects on energy metabolism and cholinergic or glutaminergic neurotransmission. Recent findings have shown that the memory-enhancing effect is steroid-sensitive. Since corticosteroids are potent modulators of gene transcription, it appears possible that the nootropics may exert a modulatory action on protein synthesis. This assumption is supported on the one hand by the fact that the nootropics improve the memory even if they are administered several hours after the learning trial, and on the other hand by the observation that their memory-enhancing effect does not become detectable until 16-24 hours after the treatment and learning trial. Provided the memory-enhancing effect in animal experiments and the therapeutic effect in patients come about by way of the same mode of action, the fact that high levels of corticosteroids suppress the effects of the nootropics could also have clinical implications: in the light of the observation that the majority of Alzheimer patients have elevated steroid levels it could explain why there is always only a small proportion of patients in clinical trials that respond to treatment with nootropics.
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Affiliation(s)
- C Mondadori
- CIBA-GEIGY LTD, Pharmaceutical Research Division, Basel, Switzerland
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Abstract
Up to now, the memory-enhancing effect of the nootropics has chiefly been investigated in the context of effects on energy metabolism and on cholinergic and glutamatergic neurotransmission. Recent studies have also shown that the effect on memory is steroid-sensitive. The present review article summarizes the available results and discusses them in the context of a new hypothesis on the mechanism of action and with respect to clinical implications.
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Affiliation(s)
- C Mondadori
- CIBA-GEIGY Limited, Pharmaceutical Research Division, Basel, Switzerland
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Chopin P, Briley M. Effects of four non-cholinergic cognitive enhancers in comparison with tacrine and galanthamine on scopolamine-induced amnesia in rats. Psychopharmacology (Berl) 1992; 106:26-30. [PMID: 1738791 DOI: 10.1007/bf02253584] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Amnesia can be induced in rats in the passive avoidance paradigm by administration of scopolamine, a central muscarinic receptor antagonist. Tacrine or galanthamine, inhibitors of acetylcholinesterase, given in conjunction with scopolamine partially reversed the scopolamine-induced deficit in passive avoidance performance. Four so-called cognitive enhancers, all widely used for the treatment of the symptoms associated with mental aging, cerebral insufficiency and senile memory disorder, were investigated in this paradigm. Piracetam, an extract of Ginkgo biloba, dihydroergocristine and a combination of raubasine with dihydroergocristine, all attenuated the amnesia induced by scopolamine. In contrast, nicergoline had no significant effect. Raubasine alone also failed to significantly attenuate scopolamine-induced amnesia, although some doses of raubasine had a non-significant tendency (P less than 0.10) to reduce the amnesia.
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Affiliation(s)
- P Chopin
- Centre de Recherche Pierre Fabre, Castres, France
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Gamzu E, Hoover TM, Gracon SI, Ninteman MV. Recent development in 2-pyrrolidinone-containing nootropics. Drug Dev Res 1989. [DOI: 10.1002/ddr.430180302] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
1. The need of the treatment of cognitive impairment due to aging or dementia has led to the search for potential cognition enhancing drugs. The various compounds presently under development represent an alternative to the cholinomimetic therapy and include new chemical entities as well as piracetam and its newer analogs. 2. Recent results from pre-clinical evaluation of the effects on learning on memory are summarized. Emphasis is put on learning and memory experiments under normal and pathological conditions. Most of the nootropics attenuate experimental amnesias induced by scopolamine, cycloheximide, ECS, hemicholinium-3 or forebrain ischemia. These findings suggest that the nootropics may be influencing a common mechanism underlying the amnesias. 3. Biochemical data suggest a potential cholinergic neuronal activity of some of the piracetam analogs. They increase high-affinity choline uptake, and antagonize scopolamine- and ECS-induced decreases in acetylcholine concentrations in the hippocampus. The mode of action of these and all other nootropic compounds, however, is still not known. 4. Despite the interesting results from learning and memory studies and from biochemical investigations, the clinical relevance of these results for amelioration of the cognitive impairment in humans remains to be proven for most of the compounds.
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Affiliation(s)
- U Schindler
- Department of CNS Pharmacology, Cassella AG, Frankfurt, Federal Republic of Germany
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