Rivastigmine Dotaz Zobrazit nápovědu
Current palliative pharmacotherapy of Alzheimer's disease based on the cholinergic hypothesis led to the development of four cholinesterase inhibitors. These compounds can bring prolongation of the symptom-free period in some patients. This is the first report directly comparing donepezil and rivastigmine plasma and brain levels in in-vivo study. Donepezil and rivastigmine were applied i.m. to rats; the dose was calculated from clinical recommendations. The samples were analysed on an Agilent 1260 Series LC with UV/VIS detector. An analytical column (Waters Spherisorb S5 W (250 mm × 4.6 i.d.; 5 μm particle size)) with guard column (Waters Spherisorb S5 W (30 mm × 4.6 mm i.d.)) was used. The mobile phase contained acetonitrile and 50 mM sodium dihydrogen phosphate (17:83; v/v); pH 3.1. The LLOQ in rat plasma was 0.5 ng/mL for donepezil and 0.8 ng/mL for rivastigmine, and the LLOQ in rat brain was 1.0 ng/mL for donepezil and 1.1 ng/mL for rivastigmine. Both compounds showed ability to target the central nervous system, with brain concentrations exceeding those in plasma. Maximum brain concentration after i.m. administration was reached in the 36 (8.34 ± 0.34 ng/mL) and 17 minute (6.18 ± 0.40 ng/mL), respectively for donepezil and rivastigmine. The differences in brain profile can be most easily expressed by plasma/brain AUCtotal ratios: donepezil ratio in the brain was nine-times higher than in plasma and rivastigmine ratio was less than two-times higher than in plasma.
- Klíčová slova
- Acetylcholinesterase inhibitors, Alzheimer’s disease, Donepezil, HPLC, Rivastigmine,
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Rivastigmine is a pseudo-irreversible cholinesterase inhibitor used for therapy of Alzheimer's disease and non-Alzheimer dementia syndromes. In humans, rivastigmine can cause significant gastrointestinal side effects that can limit its clinical use. The aim of this study was to assess the impact of rivastigmine on gastric motor function by means of electrogastrography (EGG) in experimental pigs. METHODS: Six experimental adult female pigs (Sus scrofa f. domestica, hybrids of Czech White and Landrace breeds; 3-month-old; mean weight 30.7 ± 1.2 kg) were enrolled into the study twice and created two experimental groups. In group A, a single intragastric dose of 6 mg rivastigmine hydrogen tartate was administered in the morning to fasting pigs before EGG recording. In group B, rivastigmine was administered to overnight fasting animals in a dietary bolus in the morning for 7 days (6 mg per day). On day 8, an intragastric dose of 12 mg rivastigmine was given in the morning to fasting pigs before EGG. EGG recording was accomplished by means of an EGG standalone system. Recordings from both groups were evaluated in dominant frequency and EGG power (areas of amplitudes). RESULTS: In total, 1,980 one-minute EGG intervals were evaluated. In group A, basal EGG power (median 1290.5; interquartile range 736.5-2330 μV2) was significantly higher in comparison with the power of intervals T6 (882; 577-1375; p = 0.001) and T10 (992.5; 385-2859; p = 0.032). In group B, the dominant frequency increased significantly from basal values (1.97 ± 1.57 cycles per minute) to intervals T9 (3.26 ± 2.16; p < 0.001) and T10 (2.14 ± 1.16; p = 0.012), respectively. In group B, basal EGG power (median 1030.5; interquartile range 549-5093) was significantly higher in comparison with the power of intervals T7 (692.5; 434-1476; p = 0.002) and T8 (799; 435-1463 μV2; p = 0.004). CONCLUSIONS: Both single as well as repeated intragastric administration of rivastigmine hydrogen tartrate caused a significant decrease of EGG power (areas of amplitudes) in experimental pigs. EGG power may serve as an indirect indicator of gastric motor competence. These findings might provide a possible explanation of rivastigmine-associated dyspepsia in humans.
- MeSH
- Alzheimerova nemoc * MeSH
- cholinesterasové inhibitory farmakologie MeSH
- elektromyografie MeSH
- fenylkarbamáty farmakologie MeSH
- gastrointestinální trakt MeSH
- kojenec MeSH
- lidé MeSH
- rivastigmin farmakologie MeSH
- žaludek * MeSH
- zvířata MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- cholinesterasové inhibitory MeSH
- fenylkarbamáty MeSH
- rivastigmin MeSH
A family of new compounds with sulfonamide and amide functional groups as potential Alzheimer's disease drugs were prepared by multistep synthesis. Thermal stability measurements recorded the initial decomposition in the range of 200-220°C, close above the melting point. The final compounds were tested for their ability to inhibit acetylcholinesterase and butyrylcholinesterase, and the in vitro dissolution behavior of selected compounds was studied through both lipophilic and hydrophilic matrix tablets. All nine tested derivatives were even more active in inhibiting acetylcholinesterase than the clinically used rivastigmine. Regression analysis of the obtained dissolution profiles was performed, and the effects of the pH and the release mechanism were determined. Some substances showed remarkable biological activity and became a subject of interest for further extensive study.
- Klíčová slova
- Alzheimer's disease, cholinesterase inhibitors, dissolution testing, sulfonamides, synthesis,
- MeSH
- acetylcholinesterasa metabolismus MeSH
- Alzheimerova nemoc * farmakoterapie MeSH
- butyrylcholinesterasa * metabolismus MeSH
- cholinesterasové inhibitory * farmakologie chemická syntéza chemie MeSH
- koncentrace vodíkových iontů MeSH
- lidé MeSH
- molekulární struktura MeSH
- rivastigmin farmakologie chemická syntéza chemie MeSH
- rozpustnost MeSH
- sulfonamidy * farmakologie chemie chemická syntéza MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- acetylcholinesterasa MeSH
- butyrylcholinesterasa * MeSH
- cholinesterasové inhibitory * MeSH
- rivastigmin MeSH
- sulfonamidy * MeSH
A series of twenty-five novel salicylanilide N-alkylcarbamates were investigated as potential acetylcholinesterase inhibitors. The compounds were tested for their ability to inhibit acetylcholinesterase (AChE) from electric eel (Electrophorus electricus L.). Experimental lipophilicity was determined, and the structure-activity relationships are discussed. The mode of binding in the active site of AChE was investigated by molecular docking. All the discussed compounds expressed significantly higher AChE inhibitory activity than rivastigmine and slightly lower than galanthamine. Disubstitution by chlorine in C'(₃,₄) of the aniline ring and the optimal length of hexyl-undecyl alkyl chains in the carbamate moiety provided the most active AChE inhibitors. Monochlorination in C'(₄) exhibited slightly more effective AChE inhibitors than in C'(₃). Generally it can be stated that compounds with higher lipophilicity showed higher inhibition, and the activity of the compounds is strongly dependent on the length of the N-alkyl chain.
- MeSH
- acetylcholinesterasa metabolismus MeSH
- cholinesterasové inhibitory chemie farmakologie MeSH
- Electrophorus metabolismus MeSH
- fenylkarbamáty metabolismus MeSH
- galantamin metabolismus MeSH
- karbamáty chemie farmakologie MeSH
- katalytická doména MeSH
- molekulární modely MeSH
- rivastigmin MeSH
- salicylanilidy chemie farmakologie MeSH
- simulace molekulového dockingu MeSH
- vazebná místa MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- acetylcholinesterasa MeSH
- cholinesterasové inhibitory MeSH
- fenylkarbamáty MeSH
- galantamin MeSH
- karbamáty MeSH
- rivastigmin MeSH
- salicylanilide MeSH Prohlížeč
- salicylanilidy MeSH
Impairment of mitochondrial metabolism, particularly the electron transport chain (ETC), as well as increased oxidative stress might play a significant role in pathogenesis of Alzheimer's disease (AD). Some effects of drugs used for symptomatic AD treatment may be related to their direct action on mitochondrial function. In vitro effects of pharmacologically different cognitives (galantamine, donepezil, rivastigmine, 7-MEOTA, memantine) and nootropic drugs (latrepirdine, piracetam) were investigated on selected mitochondrial parameters: activities of ETC complexes I, II + III, and IV, citrate synthase, monoamine oxidase (MAO), oxygen consumption rate, and hydrogen peroxide production of pig brain mitochondria. Complex I activity was decreased by galantamine, donepezil, and memantine; complex II + III activity was increased by galantamine. None of the tested drugs caused significant changes in the rate of mitochondrial oxygen consumption, even at high concentrations. Except galantamine, all tested drugs were selective MAO-A inhibitors. Latrepirdine, donepezil, and 7-MEOTA were found to be the most potent MAO-A inhibitors. Succinate-induced mitochondrial hydrogen peroxide production was not significantly affected by the drugs tested. The direct effect of cognitives and nootropics used in the treatment of AD on mitochondrial respiration is relatively small. The safest drugs in terms of disturbing mitochondrial function appear to be piracetam and rivastigmine. The MAO-A inhibition by cognitives and nootropics may also participate in mitochondrial neuroprotection. The results support the future research aimed at measuring the effects of currently used drugs or newly synthesized drugs on mitochondrial functioning in order to understand their mechanism of action.
- Klíčová slova
- Cognitives, Mitochondrial respiration, Monoamine oxidase, Nootropics, Reactive oxygen species,
- MeSH
- Alzheimerova nemoc metabolismus MeSH
- cholinesterasové inhibitory farmakologie MeSH
- donepezil MeSH
- galantamin metabolismus MeSH
- indany farmakologie MeSH
- kognice účinky léků MeSH
- memantin farmakologie MeSH
- mitochondrie účinky léků metabolismus MeSH
- monoaminoxidasa účinky léků metabolismus MeSH
- mozek účinky léků metabolismus MeSH
- nootropní látky farmakologie MeSH
- piperidiny farmakologie MeSH
- prasata MeSH
- rivastigmin farmakologie MeSH
- spotřeba kyslíku účinky léků MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- cholinesterasové inhibitory MeSH
- donepezil MeSH
- galantamin MeSH
- indany MeSH
- memantin MeSH
- monoaminoxidasa MeSH
- nootropní látky MeSH
- piperidiny MeSH
- rivastigmin MeSH
INTRODUCTION: Alzheimer's disease (AD) is a world-wide health problem with implications for an increasing number of people and countries. Populations suffering from AD financially strain the healthcare budgets of rich and poor countries alike. Moreover, no effective treatment is available and current drugs merely slow the progression of cognitive function deterioration and overall health status toward an inevitable end point. An increasing number of novel approaches have been tested in numerous clinical trials, but none of them has proved safe and effective for treating AD. AREAS COVERED: This review summarizes all currently available compounds (donepezil, rivastigmine, galantamine, memantine) for the management of AD, concentrating on clinical aspects such as the mechanisms of action, pharmacokinetics, pharmacodynamics and clinical trials. This review also considers the mechanisms and side effects to provide perspective on current treatment options. EXPERT OPINION: Novel approaches in the treatment of AD are being intensively tested, but so far without any major success. Patients diagnosed with AD still mostly benefit from four compounds to significantly improve cognition functions and overall health and help manage other symptoms or even prolong the symptom-free period.
- Klíčová slova
- Alzheimer's diseases, acetylcholinesterase, donepezil, galantamine, memantine, rivastigmine,
- MeSH
- Alzheimerova nemoc farmakoterapie epidemiologie patofyziologie MeSH
- antagonisté excitačních aminokyselin škodlivé účinky farmakologie terapeutické užití MeSH
- cholinesterasové inhibitory škodlivé účinky farmakologie terapeutické užití MeSH
- klinické zkoušky jako téma MeSH
- lidé MeSH
- memantin škodlivé účinky farmakologie terapeutické užití MeSH
- progrese nemoci MeSH
- racionální návrh léčiv MeSH
- výsledek terapie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- antagonisté excitačních aminokyselin MeSH
- cholinesterasové inhibitory MeSH
- memantin MeSH
Nerve agents pose a real threat to both the military and civil populations, but the current treatment of the poisoning is unsatisfactory. Thus, we studied the efficacy of prophylactic use of memantine alone or in combination with clinically used reversible acetylcholinesterase inhibitors (pyridostigmine, donepezil, rivastigmine) against soman. In addition, we tested their influence on post-exposure therapy consisting of atropine and asoxime. Pyridostigmine alone failed to decrease the acute toxicity of soman. But all clinically used acetylcholinesterase inhibitors administered alone reduced the acute toxicity, with donepezil showing the best efficacy. The combination of memantine with reversible acetylcholinesterase inhibitors attenuated soman acute toxicity significantly. The pretreatment administered alone or in combinations influenced the efficacy of post-exposure treatment in a similar fashion: (i) pyridostigmine or memantine alone did not affect the antidotal treatment, (ii) centrally acting reversible acetylcholinesterase inhibitors alone increased the antidotal treatment slightly, (iii) combination of memantine with reversible acetylcholinesterase inhibitors increased the antidotal treatment more markedly. In conclusion, memantine alone failed to decrease the acute toxicity of soman or increase post-exposure antidotal treatment efficacy. The combination of memantine with donepezil significantly increased post-exposure effectiveness (together 5.12, pretreatment alone 1.72). Both drugs, when applied together, mitigate soman toxicity and boost post-exposure treatment.
- Klíčová slova
- Donepezil, Memantine, Mice, Pyridostigmine, Rivastigmine, Soman,
- MeSH
- acetylcholinesterasa metabolismus MeSH
- antiparkinsonika aplikace a dávkování MeSH
- cholinesterasové inhibitory aplikace a dávkování toxicita MeSH
- donepezil aplikace a dávkování MeSH
- dopaminové látky aplikace a dávkování MeSH
- kombinovaná farmakoterapie MeSH
- memantin aplikace a dávkování MeSH
- myši MeSH
- preexpoziční profylaxe metody MeSH
- soman toxicita MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- acetylcholinesterasa MeSH
- antiparkinsonika MeSH
- cholinesterasové inhibitory MeSH
- donepezil MeSH
- dopaminové látky MeSH
- memantin MeSH
- soman MeSH
Different toxic compounds can target the cholinergic nervous system. Acetylcholinesterase (AChE; EC 3.1.1.7) is one of the most crucial components of the cholinergic nervous system and thus many of the toxins interact with this enzyme. As to inhibitors, nerve agents used as chemical warfare, some insecticides, and drugs influencing the cholinergic system are common examples of AChE inhibitors. Once inhibited by a neurotoxic compound, a serious cholinergic crisis can occur. On the other hand, sensitivity of AChE to the inhibition can be used for analytical purposes. In this study, a simple disposable biosensor with AChE as a recognition element was devised. AChE was immobilized onto a cellulose matrix and indoxylacetate was used as a chromogenic substrate. The enzyme reaction was assessed by the naked eye using arbitrary units and pyridostigmine, tacrine, paraoxon, carbofuran, soman and VX were assayed as selected inhibitors. A good stability of the biosensors was found, with no aging over a quarter of a year and minimal sensitivity to the interference of organic solvents. The limit of detection ranged from 10 to 100 nmol/L for the compounds tested with a sample volume of 40 µL.
- Klíčová slova
- Ellman′s method, acetylcholinesterase, carbofuran, indoxylacetate, inhibitor, pesticide, rivastigmine, sarin,
- Publikační typ
- časopisecké články MeSH
Based on the presence of dialkyl phosphate moiety, we evaluated twenty-seven salicylanilide diethyl phosphates (diethyl [2-(phenylcarbamoyl)phenyl] phosphates) for the inhibition of acetylcholinesterase (AChE) from electric eel (Electrophorus electricus L.) and butyrylcholinesterase (BChE) from equine serum. Ellman's spectrophotometric method was used. The inhibitory activity (expressed as IC50 values) was compared with that of the established drugs galantamine and rivastigmine. Salicylanilide diethyl phosphates showed significant activity against both cholinesterases with IC50 values from 0.903 to 86.3 μM. IC50s for BChE were comparatively lower than those obtained for AChE. All of the investigated compounds showed higher inhibition of AChE than rivastigmine, and six of them inhibited BChE more effectively than both rivastigmine and galantamine. In general, derivatives of 4-chlorosalicylic acid showed enhanced activity when compared to derivatives of 5-halogenated salicylic acids, especially against BChE. The most effective inhibitor of AChE was O-{5-chloro-2-[(3-bromophenyl)carbamoyl]phenyl} O,O-diethyl phosphate with IC50 of 35.4 μM, which is also one of the most potent inhibitors of BChE. O-{5-Chloro-2-[(3,4-dichlorophenyl)carbamoyl]phenyl} O,O-diethyl phosphate exhibited in vitro the strongest inhibition of BChE (0.90 μM). Salicylanilide diethyl phosphates act as pseudo-irreversible cholinesterases inhibitors.
- Klíčová slova
- Acetylcholinesterase, Butyrylcholinesterase, Enzyme inhibition, Organophosphate, Salicylanilide diethyl phosphate,
- MeSH
- acetylcholinesterasa účinky léků MeSH
- butyrylcholinesterasa účinky léků MeSH
- cholinesterasové inhibitory chemie farmakologie MeSH
- estery MeSH
- inhibiční koncentrace 50 MeSH
- salicylanilidy chemie farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- acetylcholinesterasa MeSH
- butyrylcholinesterasa MeSH
- cholinesterasové inhibitory MeSH
- estery MeSH
- salicylanilide MeSH Prohlížeč
- salicylanilidy MeSH
A series of 14 target benzyl [2-(arylsulfamoyl)-1-substituted-ethyl]carbamates was prepared by multi-step synthesis and characterized. All the final compounds were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in vitro, and the selectivity index (SI) was determined. Except for three compounds, all compounds showed strong preferential inhibition of BChE, and nine compounds were even more active than the clinically used rivastigmine. Benzyl {(2S)-1-[(2-methoxybenzyl)sulfamoyl]-4-methylpentan-2-yl}carbamate (5k), benzyl {(2S)-1-[(4-chlorobenzyl)sulfamoyl]-4-methylpentan-2-yl}carbamate (5j), and benzyl [(2S)-1-(benzylsulfamoyl)-4-methylpentan-2-yl]carbamate (5c) showed the highest BChE inhibition (IC50 = 4.33, 6.57, and 8.52 µM, respectively), indicating that derivatives 5c and 5j had approximately 5-fold higher inhibitory activity against BChE than rivastigmine, and 5k was even 9-fold more effective than rivastigmine. In addition, the selectivity index of 5c and 5j was approx. 10 and that of 5k was even 34. The process of carbamylation and reactivation of BChE was studied for the most active derivatives 5k, 5j. The detailed information about the mode of binding of these compounds to the active site of both BChE and AChE was obtained in a molecular modeling study. In this study, combined techniques (docking, molecular dynamic simulations, and QTAIM (quantum theory of atoms in molecules) calculations) were employed.
- Klíčová slova
- bioassays, carbamates, cholinesterase inhibitors, molecular modeling, sulfonamides, synthesis,
- MeSH
- acetylcholinesterasa metabolismus MeSH
- butyrylcholinesterasa metabolismus MeSH
- cholinesterasové inhibitory chemie MeSH
- karbamáty chemická syntéza chemie MeSH
- katalytická doména MeSH
- lidé MeSH
- simulace molekulární dynamiky MeSH
- simulace molekulového dockingu MeSH
- sulfonamidy chemická syntéza chemie MeSH
- vazebná místa MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- acetylcholinesterasa MeSH
- BCHE protein, human MeSH Prohlížeč
- butyrylcholinesterasa MeSH
- cholinesterasové inhibitory MeSH
- karbamáty MeSH
- sulfonamidy MeSH