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Frontiers in Neurology Oct 2013Modafinil, in its two clinical formulations (Provigil(®) and Nuvigil(®)), is a widely prescribed wake-promoting therapeutic agent. It binds competitively to the... (Review)
Review
Modafinil, in its two clinical formulations (Provigil(®) and Nuvigil(®)), is a widely prescribed wake-promoting therapeutic agent. It binds competitively to the cell-membrane dopamine (DA) transporter and is dependent on catecholaminergic (dopaminergic and adrenergic) signaling for its wake-promoting effects. The clinical spectrum of effects for modafinil is distinct from the effects seen with other catecholaminergic agents. Relative to other commonly used agents that act through catecholaminergic mechanisms, modafinil has a relatively low abuse potential, produces wakefulness with an attenuated compensatory sleep recovery thereafter, and does not ameliorate cataplexy in narcolepsy. These clinically relevant phenomenological differences between modafinil and agents such as amphetamines and cocaine do not eliminate catecholaminergic effects as a possible mediator of its wake-promoting action; they merely reflect its unique pharmacological profile. Modafinil is an exceptionally weak, but apparently very selective, DA transporter inhibitor. The pharmacodynamic response to modafinil, as measured by DA levels in brain microdialyzate, is protracted relative to other agents that act via catecholaminergic mechanisms. The conformational constraints on the interaction of modafinil with the DA transporter - and probably, as a consequence, its effects on trace amine receptor signaling in the catecholaminergic cell - are unique among catecholaminergic agents. These unique pharmacological properties of modafinil should be considered both in seeking to thoroughly understand its putatively elusive mechanism of action and in the design of novel therapeutic agents.
PubMed: 24109471
DOI: 10.3389/fneur.2013.00139 -
Innovations in Clinical Neuroscience Apr 2018: The authors sought to assess the literature evidence on the efficacy of modafinil use in patients with fatigue or excessive daytime sleepiness (EDS) secondary to... (Review)
Review
: The authors sought to assess the literature evidence on the efficacy of modafinil use in patients with fatigue or excessive daytime sleepiness (EDS) secondary to traumatic brain injury (TBI). : A literature search of Medline and PubMed was performed using the EBSCOhost database. Primary literature, observational studies, meta-analyses, case reports, and systematic reviews were assessed for content regarding modafinil and psychostimulant use in patients with TBI. Of the 23 articles collected, three randomized, controlled studies, three observational studies, one case report, and two systematic reviews gave a description of modafinil use in TBI patients. : Modafinil is a central nervous system stimulant with well-established effectiveness in the treatment of narcolepsy and shift-work sleep disorder. There is conflicting evidence about the benefits of modafinil in the treatment of fatigue and EDS secondary to TBI. One randomized, controlled study states that modafinil does not significantly improve patient wakefulness, while another concludes that modafinil corrects EDS but not fatigue. An observational study provides evidence that modafinil increases alertness in fatigued patients with past medical history of brainstem diencephalic stroke or multiple sclerosis. Modafinil appears to have the potential to improve wakefulness in patients with TBI. A prospective, double-blinded, randomized, crossover trial of modafinil for the management of fatigue in ischemic stroke patients is currently being conducted, and further studies demonstrating consistent results are needed before making a conclusive decision.
PubMed: 29707422
DOI: No ID Found -
Pharmacology, Biochemistry, and Behavior Aug 2011Whether drugs that enhance cognition in healthy individuals will appear in the near future has become a topic of considerable interest. We address this possibility using... (Review)
Review
Whether drugs that enhance cognition in healthy individuals will appear in the near future has become a topic of considerable interest. We address this possibility using a three variable system (psychological effect, neurobiological mechanism, and efficiency vs. capabilities) for classifying candidates. Ritalin and modafinil, two currently available compounds, operate on primary psychological states that in turn affect cognitive operations (attention and memory), but there is little evidence that these effects translate into improvements in complex cognitive processing. A second category of potential enhancers includes agents that improve memory encoding, generally without large changes in primary psychological states. Unfortunately, there is little information on how these compounds affect cognitive performance in standard psychological tests. Recent experiments have identified a number of sites at which memory drugs could, in principle, manipulate the cell biological systems underlying the learning-related long-term potentiation (LTP) effect; this may explain the remarkable diversity of memory promoting compounds. Indeed, many of these agents are known to have positive effects on LTP. A possible third category of enhancement drugs directed specifically at integrated cognitive operations is nearly empty. From a neurobiological perspective, two plausible candidate classes have emerged that both target the fast excitatory transmission responsible for communication within cortical networks. One acts on nicotinic receptors (alpha7 and alpha4) that regulate release of the neurotransmitter glutamate while the other ('ampakines') allosterically modulates the glutamate receptors mediating the post-synaptic response (EPSCs). Brain imaging in primates has shown that ampakines expand cortical networks engaged by a complex task; coupled with behavioral data, these findings provide evidence for the possibility of generating new cognitive capabilities. Finally, we suggest that continuing advances in behavioral sciences provide new opportunities for translational work, and that discussions of the social impact of cognitive enhancers have failed to consider the distinction between effects on efficiency vs. new capabilities.
Topics: Animals; Benzhydryl Compounds; Cognition; Humans; Long-Term Potentiation; Memory; Methylphenidate; Modafinil; Models, Neurological; Models, Psychological; Nootropic Agents; Translational Research, Biomedical
PubMed: 21215768
DOI: 10.1016/j.pbb.2010.12.024 -
Schizophrenia Bulletin Nov 2007Advances in molecular biology have led to new peptides and proteins being discovered on a regular basis, including the isolation of a number of neurotransmitter... (Review)
Review
Advances in molecular biology have led to new peptides and proteins being discovered on a regular basis, including the isolation of a number of neurotransmitter candidates. Rarely, however, do these immediately capture the attention of the scientific community. The isolation and characterization of the orexin/hypocretin peptides a decade ago resulted in a slew of studies that have helped clarified their diverse functions, including prominent roles in arousal and appetitive behavior. A number of recent studies have detailed the role of the orexins/hypocretins in attention and cognition and uncovered an involvement in schizophrenia and the mechanisms of action of antipsychotic drugs (APDs). This issue of Schizophrenia Bulletin presents several articles that review our current understanding and point to future directions for the study of the orexins/hypocretins in schizophrenia and APD actions.
Topics: Benzhydryl Compounds; Brain; Central Nervous System Stimulants; Chromosomes, Human, Pair 17; Humans; Intracellular Signaling Peptides and Proteins; Modafinil; Neuropeptides; Orexins; Schizophrenia
PubMed: 17728265
DOI: 10.1093/schbul/sbm096 -
Journal of Clinical Medicine Oct 2022Attention deficit hyperactivity disorder (ADHD) affects 6.4 million children in the United States of America. Children and adolescents, the main consumers of ADHD...
Attention deficit hyperactivity disorder (ADHD) affects 6.4 million children in the United States of America. Children and adolescents, the main consumers of ADHD medication, are in the bone growth phase, which extends over a period of up to two decades. Thus, impaired proliferation and maturation of chondrocytes and osteoblasts can result in impaired bone formation. The aim of this study is to investigate, for the first time, the effects of the ADHD-medication modafinil, atomoxetine and guanfacine on bone growth and repair in vitro. Using two-dimensional and three-dimensional cell models, we investigated the chondrogenic/osteogenic differentiation, proliferation and viability of human mesenchymal progenitor cells. Real-time cell proliferation was measured by xCELLigence. Live/dead staining and size measurement of hMSC- and MG63 monolayer and spheroids were performed after administration of therapeutic plasma concentrations of modafinil, atomoxetine and guanfacine. Chondrogenic differentiation was quantified by RTqPCR. The chondrogenic and osteogenic differentiation was evaluated by histological cryo-sections. Modafinil, atomoxetine and guanfacine reduced chondrogenic and osteogenic differentiation terms of transcript expression and at the histological level. Cell viability of the MG63- and hMSC monolayer was not impeded by ADHD-medication. Our in vitro results indicate that modafinil, atomoxetine and guanfacine may impair chondrogenic and osteogenic differentiation in a 3D model reflecting the in vivo physiologic condition.
PubMed: 36294540
DOI: 10.3390/jcm11206218 -
The Cochrane Database of Systematic... Nov 2022Cognitive deficits are common in people who have received cranial irradiation and have a serious impact on daily functioning and quality of life. The benefit of... (Review)
Review
BACKGROUND
Cognitive deficits are common in people who have received cranial irradiation and have a serious impact on daily functioning and quality of life. The benefit of pharmacological and non-pharmacological treatment of cognitive deficits in this population is unclear. This is an updated version of the original Cochrane Review published in Issue 12, 2014.
OBJECTIVES
To assess the effectiveness of interventions for preventing or ameliorating cognitive deficits in adults treated with cranial irradiation.
SEARCH METHODS
For this review update we searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE via Ovid, Embase via Ovid, and PsycInfo via Ovid to 12 September 2022.
SELECTION CRITERIA
We included randomised controlled (RCTs) trials that evaluated pharmacological or non-pharmacological interventions in cranial irradiated adults, with objective cognitive functioning as a primary or secondary outcome measure.
DATA COLLECTION AND ANALYSIS
Two review authors (MK, JD) independently extracted data from selected studies and carried out a risk of bias assessment. Cognitive function, fatigue and mood outcomes were reported. No data were pooled.
MAIN RESULTS
Eight studies met the inclusion criteria and were included in this updated review. Six were from the original version of the review, and two more were added when the search was updated. Nineteen further studies were assessed as part of this update but did not fulfil the inclusion criteria. Of the eight included studies, four studies investigated "prevention" of cognitive problems (during radiotherapy and follow-up) and four studies investigated "amelioration" (interventions to treat cognitive impairment as a late complication of radiotherapy). There were five pharmacological studies (two studies on prevention and three in amelioration) and three non-pharmacological studies (two on prevention and one in amelioration). Due to differences between studies in the interventions being evaluated, a meta-analysis was not possible. Studies in early radiotherapy treatment phase (five studies) Pharmacological studies in the "early radiotherapy treatment phase" were designed to prevent or ameliorate cognitive deficits and included drugs used in dementia (memantine) and fatigue (d-threo-methylphenidate hydrochloride). Non-pharmacological studies in the "early radiotherapy treatment phase" included a ketogenic diet and a two-week cognitive rehabilitation and problem-solving programme. In the memantine study, the primary cognitive outcome of memory at six months did not reach significance, but there was significant improvement in overall cognitive function compared to placebo, with similar adverse events across groups. The d-threo-methylphenidate hydrochloride study found no statistically significant difference between arms, with few adverse events. The study of a calorie-restricted ketogenic diet found no effect, although a lower than expected calorie intake in the control group complicates interpretation of the results. The study investigating the utility of a rehabilitation program did not carry out a statistical comparison of cognitive performance between groups. Studies in delayed radiation or late effect phase (four studies) The "amelioration" pharmacological studies to treat cognitive complications of radiotherapy included drugs used in dementia (donepezil) or psychostimulants (methylphenidate and modafinil). Non-pharmacological measures included cognitive rehabilitation and problem solving (Goal Management Training). These studies included patients with cognitive problems at entry who had "stable" brain cancer. The donepezil study did not find an improvement in the primary cognitive outcome of overall cognitive performance, but did find improvement in an individual test of memory, compared to placebo; adverse events were not reported. A study comparing methylphenidate with modafinil found improvements in cognitive function in both the methylphenidate and modafinil arms; few adverse events were reported. Another study comparing two different doses of modafinil combined treatment arms and found improvements across all cognitive tests, however, a number of adverse events were reported. Both studies were limited by a small sample size. The Goal Management Training study suggested a benefit of the intervention, a behavioural intervention that combined mindfulness and strategy training, on executive function and processing speed. There were a number of limitations across studies and few were without high risks of bias.
AUTHORS' CONCLUSIONS
In this update, limited additional evidence was found for the treatment or amelioration of cognitive deficits in adults treated with cranial irradiation. As concluded in the original review, there is supportive evidence that memantine may help prevent cognitive deficits for adults with brain metastases receiving cranial irradiation. There is supportive evidence that donepezil, methylphenidate and modafinil may have a role in treating cognitive deficits in adults with brain tumours who have been treated with cranial irradiation; patient withdrawal affected the statistical power of these studies. Further research that tries to minimise the withdrawal of consent, and subsequently reduce the requirement for imputation procedures, may offer a higher certainty of evidence. There is evidence from only a single small study to support non-pharmacological interventions in the amelioration of cognitive deficits. Further research is required.
Topics: Adult; Humans; Modafinil; Donepezil; Memantine; Quality of Life; Cognitive Dysfunction; Cranial Irradiation; Cognition; Methylphenidate; Brain Neoplasms; Fatigue; Dementia
PubMed: 36427235
DOI: 10.1002/14651858.CD011335.pub3 -
Molecules (Basel, Switzerland) Jul 2023Psychostimulant use disorders (PSUD) affect a growing number of men and women and exert sizable public health and economic burdens on our global society. Notably, there... (Review)
Review
Psychostimulant use disorders (PSUD) affect a growing number of men and women and exert sizable public health and economic burdens on our global society. Notably, there are some sex differences in the onset of dependence, relapse rates, and treatment success with PSUD observed in preclinical and clinical studies. The subtle sex differences observed in the behavioral aspects of PSUD may be associated with differences in the neurochemistry of the dopaminergic system between sexes. Preclinically, psychostimulants have been shown to increase synaptic dopamine (DA) levels and may downregulate the dopamine transporter (DAT). This effect is greatest in females during the high estradiol phase of the estrous cycle. Interestingly, women have been shown to be more likely to begin drug use at younger ages and report higher levels of desire to use cocaine than males. Even though there is currently no FDA-approved medication, modafinil, a DAT inhibitor approved for use in the treatment of narcolepsy and sleep disorders, has shown promise in the treatment of PSUD among specific populations of affected individuals. In this review, we highlight the therapeutic potential of modafinil and other atypical DAT inhibitors focusing on the lack of sex differences in the actions of these agents.
Topics: Female; Humans; Male; Dopamine Uptake Inhibitors; Modafinil; Sex Characteristics; Benzhydryl Compounds; Central Nervous System Stimulants; Cocaine; Dopamine
PubMed: 37446929
DOI: 10.3390/molecules28135270 -
PloS One 2013Modafinil is a novel wake-promoting agent approved by the FDA ameliorating excessive daytime sleepiness (EDS) in three disorders: narcolepsy, shift work sleep disorder... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Modafinil is a novel wake-promoting agent approved by the FDA ameliorating excessive daytime sleepiness (EDS) in three disorders: narcolepsy, shift work sleep disorder and obstructive sleep apnea. Existing trials of modafinil for fatigue and EDS associated with neurological disorders provided inconsistent results. This meta-analysis was aimed to assess drug safety and effects of modafinil on fatigue and EDS associated with neurological disorders.
METHODS
A comprehensive literature review was conducted in order to identify published studies assessing the effects of modafinil on fatigue and EDS associated with neurological disorders. Primary outcomes included fatigue and EDS. Secondary outcomes included depression and adverse effects.
FINDINGS
Ten randomized controlled trials were identified including 4 studies of Parkinson's disease (PD), 3 of multiple sclerosis (MS), 2 of traumatic brain injury (TBI) and 1 of post-polio syndrome (PPS). A total of 535 patients were enrolled. Our results suggested a therapeutic effect of modafinil on fatigue in TBI (MD -0.82 95% CI -1.54 - -0.11 p=0.02, I(2)=0%), while a beneficial effect of modafinil on fatigue was not confirmed in the pooled studies of PD or MS. Treatment results demonstrated a clear beneficial effect of modafinil on EDS in patients with PD (MD -2.45 95% CI -4.00 - -0.91 p=0.002 I(2)=14%), but not with MS and TBI. No difference was seen between modafinil and placebo treatments in patients with PPS. Modafinil seemed to have no therapeutic effect on depression. Adverse events were similar between modafinil and placebo groups except that more patients were found with insomnia and nausea in modafinil group.
CONCLUSIONS
Existing trials of modafinil for fatigue and EDS associated with PD, MS, TBI and PPS provided inconsistent results. The majority of the studies had small sample sizes. Modafinil is not yet sufficient to be recommended for these medical conditions until solid data are available.
Topics: Benzhydryl Compounds; Depression; Disorders of Excessive Somnolence; Fatigue; Humans; Modafinil
PubMed: 24312590
DOI: 10.1371/journal.pone.0081802 -
Iranian Journal of Child Neurology 2022Given the importance of having a continuous performance for the academic and social life of children with attention-deficit/hyperactivity disorder (ADHD), in this study,...
OBJECTIVES
Given the importance of having a continuous performance for the academic and social life of children with attention-deficit/hyperactivity disorder (ADHD), in this study, a Continuous Performance Test (CPT) was used to compare the effect of long-acting methylphenidate and modafinil on attention and impulsivity of these children.
MATERIALS & METHODS
A randomized clinical trial was conducted on 50 children with ADHD aged 6 to 12 years in the child and adolescent psychiatric departments of Imam Hossein and Mofid hospitals, Tehran, Iran. The children were selected by availability sampling and randomly assigned into two equal groups (n=25 in each). While the first group was treated with long-acting methylphenidate, the second was treated with modafinil for 14 days. The CPT was carried out before and after the treatment. The obtained data were analyzed by F and t tests.
RESULTS
Long-acting methylphenidate and modafinil were both effective in improving attention and impulsivity in children with ADHD. There was no significant difference between the two drugs in terms of effectiveness on attention and impulsivity.
CONCLUSION
The findings of this study showed that long-acting methylphenidate and modafinil are equally effective in improving attention and impulsivity in children with ADHD aged 6 to 12 years.
PubMed: 36204437
DOI: 10.22037/ijcn.v16i2.32541 -
Biomedicine & Pharmacotherapy =... Dec 2021Small- and intermediate-conductance Ca-activated K channels, K2.3 and K3.1, are involved in cellular signaling processes associated with inflammation and fibrosis. K2.3...
Small- and intermediate-conductance Ca-activated K channels, K2.3 and K3.1, are involved in cellular signaling processes associated with inflammation and fibrosis. K2.3 and K3.1 are upregulated by proinflammatory cytokines and profibrotic growth factors. Cyclic AMP, which downregulates K2.3 and K3.1, is elevated by modafinil in cells; accordingly, we investigated whether modafinil exerts anti-inflammatory and anti-fibrotic responses via K2.3- and K3.1-mediated pathways in high-fat diet (HFD)- or thioacetamide-induced liver disease models in mice. Modafinil was administered orally in the form of a racemate, (R)-isomer, or (S)-isomer. We also determined whether the treatment targeted the profibrotic activity of hepatic stellate cells using immortalized human hepatic stellate cells (LX-2 cells). Modafinil improved HFD- or thioacetamide-induced changes compared to the control, leading to a reduced inflammatory response, collagen deposition, and α-smooth muscle actin expression both in vivo and in vitro. However, modafinil did not relieve HFD-induced steatosis. There were no significant differences in the effects of the (R)- and (S)-isomers of modafinil. K2.3 and K3.1 were upregulated and catalase was downregulated in liver tissues from thioacetamide- or HFD-induced liver disease models or in TGF-β-treated LX-2 cells. TGF-β-induced upregulation of K2.3, K3.1, collagen, and α-smooth muscle actin and downregulation of catalase were reversed by modafinil, polyethylene glycol catalase, N-acetylcysteine, siRNA against K2.3 or K3.1, and Epac inhibitors. Our investigation revealed that modafinil attenuated inflammatory and fibrotic progression via K2.3- and K3.1-mediated pathways in nonalcoholic hepatitis, suggesting that inhibiting K2.3- and K3.1-mediated signaling may serve as a novel therapeutic approach for inflammatory and fibrotic liver diseases.
Topics: Actins; Animals; Anti-Inflammatory Agents, Non-Steroidal; Cell Line; Collagen; Diet, High-Fat; Fatty Liver; Hepatic Stellate Cells; Humans; Intermediate-Conductance Calcium-Activated Potassium Channels; Liver Cirrhosis; Male; Mice; Mice, Inbred C57BL; Modafinil; Non-alcoholic Fatty Liver Disease; Small-Conductance Calcium-Activated Potassium Channels; Stereoisomerism; Thioacetamide
PubMed: 34794237
DOI: 10.1016/j.biopha.2021.112372