L-deprenyl in Alzheimer's disease. Preliminary evidence for behavioral change with monoamine oxidase B inhibition

A Systematic Review of Pharmacological Interventions for Apathy in Aging Neurocognitive Disorders

OBJECTIVE

Apathy, a frequent neuropsychiatric symptom in aging neurocognitive disorders, has been associated with cognitive decline and functional disability. Therefore, timely provision of pharmacological interventions for apathy is greatly needed.

DESIGN

A systematical literature review of existing studies was conducted up to 30 May 2023 in several databases (PubMed, PsychInfo, Cochrane, Google Scholar, etc.) that included randomized controlled trials (RCTs) and meta-analyses assessing pharmacological treatments for apathy in aging neurocognitive disorders. The quality of the studies was appraised.

RESULTS

In patients with Alzheimer's Disease (AD), donepezil, galantamine, rivastigmine, methylphenidate, and gingko biloba were proven efficacious for apathy, while rivastigmine, cognitive enhancer IRL752 and piribedil were found to be beneficial in patients with Parkinson's Disease (PD) and agomelatine in patients with Frontotemporal Dementia (FD). The extensive proportion of RCTs in which apathy was used as a secondary outcome measure, along with the considerable methodological heterogeneity, did not allow the evaluation of group effects.

CONCLUSIONS

Pharmacological interventions for apathy in aging neurocognitive disorders are complex and under-investigated. The continuation of systematic research efforts and the provision of individualized treatment for patients suffering from these disorders is vital.

Discovery of reversible selective monoamine oxidase B inhibitors with anti-acetylcholinesterase activity derived from 4-oxo-N-4-diphenyl butanamides

Aim: Multitargeted drugs are essential for the treatment of various neurodegenerative disorders, because of their complex nature. This study aimed to develop novel small molecules as selective monoamine oxidase B (MAO-B) inhibitors with cholinesterase inhibition. Materials & methods: With the help of fragment-based drug design, some 4-oxo-N-4-diphenyl butanamides were designed and synthesized as MAO-B inhibitors with anti-acetylcholinesterase (AChE) activity. Results: Compound 6m showed the best neuroprotection, with reversible selective MAO-B inhibition activity (IC₅₀ = 11.54 ± 0.64 nM). Compounds 6b, 6h, 6j, 6n and 6p (IC₅₀ = 20.90 ± 0.50, 17.25 ± 0.90, 15.85 ± 0.16, 16.81 ± 0.85 and 25.19 ± 0.17 nM, respectively) also appeared as potent and selective MAO-B inhibitors with anti-AChE activity. Conclusion: The present study suggests potent, neuroprotective and nontoxic lead compounds as selective MAO-B inhibitors with anti-AChE activity.

Apathy as a Treatment Target in Alzheimer's Disease: Implications for Clinical Trials

Apathy is one of the most prevalent, stable and persistent neuropsychiatric symptom across the neurocognitive disorders spectrum. Recent advances in understanding of phenomenology, neurobiology and intervention trials highlight apathy as an important target for clinical intervention. We conducted a comprehensive review and critical evaluation of recent advances to determine the evidence-based suggestions for future trial designs. This review focused on 4 key areas: 1) pre-dementia states; 2) assessment; 3) mechanisms/biomarkers and 4) treatment/intervention efficacy. Considerable progress has been made in understanding apathy as a treatment target and appreciating pharmacological and non-pharmacological apathy treatment interventions. Areas requiring greater investigation include: diagnostic procedures, symptom measurement, understanding the biological mechanisms/biomarkers of apathy, and a well-formed approach to the development of treatment strategies. A better understanding of the subdomains and biological mechanisms of apathy will advance apathy as a treatment target for clinical trials.

Multi-Target-Directed Ligands as an Effective Strategy for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is a complex neurological disorder, and multiple pathological factors are believed to be involved in the genesis and progression of the disease. A number of hypotheses, including Acetylcholinesterase, Monoamine oxidase, β-Amyloid, Tau protein, etc., have been proposed for the initiation and progression of the disease. At present, acetylcholine esterase inhibitors and memantine (NMDAR antagonist) are the only approved therapies for the symptomatic management of AD. Most of these single-target drugs have miserably failed in the treatment or halting the progression of the disease. Multi-factorial diseases like AD require complex treatment strategies that involve simultaneous modulation of a network of interacting targets. Since the last few years, Multi-Target-Directed Ligands (MTDLs) strategy, drugs that can simultaneously hit multiple targets, is being explored as an effective therapeutic approach for the treatment of AD. In the current review article, the authors have briefly described various pathogenic pathways associated with AD. The importance of Multi-Target-Directed Ligands and their design strategies in recently reported articles have been discussed in detail. Potent leads are identified through various structure-activity relationship studies, and their drug-like characteristics are described. Recently developed promising compounds have been summarized in the article. Some of these MTDLs with balanced activity profiles against different targets have the potential to be developed as drug candidates for the treatment of AD.

A Proteotranscriptomic-Based Computational Drug-Repositioning Method for Alzheimer's Disease

Numerous clinical trials of drug candidates for Alzheimer’s disease (AD) have failed, and computational drug repositioning approaches using omics data have been proposed as effective alternative approaches to the discovery of drug candidates. However, little multi-omics data is available for AD, due to limited availability of brain tissues. Even if omics data exist, systematic drug repurposing study for AD has suffered from lack of big data, insufficient clinical information, and difficulty in data integration on account of sample heterogeneity derived from poor diagnosis or shortage of qualified post-mortem tissue. In this study, we developed a proteotranscriptomic-based computational drug repositioning method named Drug Repositioning Perturbation Score/Class (DRPS/C) based on inverse associations between disease- and drug-induced gene and protein perturbation patterns, incorporating pharmacogenomic knowledge. We constructed a Drug-induced Gene Perturbation Signature Database (DGPSD) comprised of 61,019 gene signatures perturbed by 1,520 drugs from the Connectivity Map (CMap) and the L1000 CMap. Drugs were classified into three DRPCs (High, Intermediate, and Low) according to DRPSs that were calculated using drug- and disease-induced gene perturbation signatures from DGPSD and The Cancer Genome Atlas (TCGA), respectively. The DRPS/C method was evaluated using the area under the ROC curve, with a prescribed drug list from TCGA as the gold standard. Glioblastoma had the highest AUC. To predict anti-AD drugs, DRPS were calculated using DGPSD and AD-induced gene/protein perturbation signatures generated from RNA-seq, microarray and proteomic datasets in the Synapse database, and the drugs were classified into DRPCs. We predicted 31 potential anti-AD drug candidates commonly belonged to high DRPCs of transcriptomic and proteomic signatures. Of these, four drugs classified into the nervous system group of Anatomical Therapeutic Chemical (ATC) system are voltage-gated sodium channel blockers (bupivacaine, topiramate) and monamine oxidase inhibitors (selegiline, iproniazid), and their mechanism of action was inferred from a potential anti-AD drug perspective. Our approach suggests a shortcut to discover new efficacy of drugs for AD.

Unmet Needs in Pharmacological Treatment of Apathy in Alzheimer's Disease: A Systematic Review

Background: Apathy is one of the most prevalent neuropsychiatric symptoms encountered in Alzheimer’s disease (AD) and may be an early sign in the development of dementia persisting over the disease course. It has been associated with poor disease outcome, impaired daily functioning, and significant caregiver distress. Early diagnosis and timely treatment of apathy in AD are of great importance. However, approved agents for apathy are still missing.

Methods: Within this context, we conducted an extensive electronic search in the databases included in the National Library of Medicine, PsychInfo, and Google Scholar for studies that have investigated the effect of pharmacological treatments in apathy in AD. There were no limitations regarding study design and all care settings were considered for inclusion. Structured measures for level of evidence and study quality were employed to evaluate the results.

Results: A total of 1,607 records were identified; 1,483 records remained after the removal of duplicates and were screened; 166 full-text articles were selected and assessed for eligibility and a remaining 90 unique studies and relevant reviews were included in the qualitative synthesis. Acetylcholinesterase inhibitors, gingko biloba, and methylphenidate were found to be successful in reducing apathy in patients with AD. Methodological heterogeneity in the studies and the small amount of studies where apathy was the primary outcome are limiting factors to assess for group effects.

Conclusions: Pharmacological treatment of apathy in AD is an underexplored field. Standardized and systematic efforts are needed to establish a possible treatment benefit. Elucidating the pathophysiology of apathy and its components or subtypes will inform disease models and mechanistic drug studies that can quantify a benefit from specific agents for specific AD groups.

Drug treatment for early Alzheimer's disease

Alzheimer's disease is likely to be one of the challenges for the early part of the 21st century. Better knowledge of the molecular biology, genetics and pathogenesis of the condition have led to a host of psychopharmacological compounds being developed which may help in its the treatment, while epidemiological studies have suggested that existing treatments for other chronic conditions may have an effect on the presentation of Alzheimer's disease.

Pharmacological and Nonpharmacological Treatment for Apathy in Alzheimer Disease : A systematic review across modalities

OBJECTIVE

Apathy is one of the most frequent neuropsychiatric symptoms encountered in Alzheimer disease (AD). Early diagnosis and timely treatment of apathy in AD seem to be of great importance, since apathy has been associated with poor disease outcome, reduced daily functioning, and caregiver distress.

DESIGN

Within this context, we conducted an extensive electronic search from the databases included in the National Library of Medicine as well as PsychInfo and Google Scholar for studies that have investigated the effect of pharmacological and nonpharmacological treatments of apathy in AD.

RESULTS

Acetylcholinesterase inhibitors, gingko biloba, methylphenidate, and a variety of nonpharmacological interventions were found to be successful in reducing apathy in patients with AD. Methodological heterogeneity of the studies and the small amount of studies where apathy was a primary outcome measure are limiting factors to evaluate for group effects.

CONCLUSION

Treatment of apathy in AD is a complicated and an underexplored field. Standardized and systematic efforts primarily focused on the study of apathy in AD may establish a benefit from individualized treatment for specific disease groups that would stem from a combination of both pharmacological and nonpharmacological interventions.

The significance of selegiline/(-)-deprenyl after 50 years in research and therapy (1965-2015)

Deprenyl/Selegiline (DEP), created by Joseph Knoll in the 1960s, registered in more than 60 countries to treat Parkinson's disease, Alzheimer's disease, major depressive disorder; and used as an anti-aging drug, achieved its place in research and therapy as the first selective inhibitor of B-type monoamine oxidase (MAO-B). The demonstration that the DEP analog (-)-1-phenyl-2-propylaminopentane devoid of MAO inhibitory property, enhanced like DEP the activity of the catecholaminergic brain engine revealed that this effect is unrelated to the selective inhibition of MAO-B. β-Phenylethylamine (PEA), the important trace-amine in the mammalian brain, is known to be a releaser of catecholamines. Amphetamine and methamphetamine, the best known synthetic PEA derivatives are also releasers of catecholamines like their parent compound. DEP is a unique synthetic PEA derivative devoid of the catecholamine releasing property. As the releasing effect conceals the catecholaminergic activity enhancer (CAE) effect, it remained undiscovered until DEP uncovered that PEA is a natural CAE substance; and only releases catecholamines in high concentration. Discovering that tryptamine is a natural enhancer of catecholaminergic and serotonergic neurons catalyzed the development of R-(-)-1-(benzofuran-2-yl)-2-propylaminopentane (BPAP); the most potent and selective enhancer substance, and it exerts its enhancer effect in 0.0001 mg kg^-1. DEP and BPAP initiated an analysis of the enhancer regulation in the mammalian brain. Studies regarding the nature of the enhancer regulation revealed that this regulation is enhanced after weaning and sex hormones return it to the pre-weaning level. Thus, sex hormones elicit the transition of the developmental phase of life into the post-developmental, downhill (aging) period. The aging-related, slow decline in the enhancer regulation of the catecholaminergic brain engine, the main activator of the cortex, is the prime factor of brain aging. The enhancer regulation's decay in the most rapidly aging dopaminergic system is, for example, mainly responsible for the decline in learning ability and sexual activity over time. According to the Knoll concept, based on two longevity studies performed on male rats, to keep the catecholaminergic brain engine, from the beginning of the downhill period of life, via the administration of a small daily dose of a CAE substance (presently DEP is the only available drug) on a higher activity level, thus to fight against the physiological aging-related slow decay of the catecholaminergic system, is a suitable anti-aging therapy. As our present knowledge regarding the enhancer regulation in the mammalian brain is like seeing a peak of an iceberg, the future of this new line of brain research looks promising from both theoretical and practical aspects.

GABA from reactive astrocytes impairs memory in mouse models of Alzheimer's disease

In Alzheimer's disease (AD), memory impairment is the most prominent feature that afflicts patients and their families. Although reactive astrocytes have been observed around amyloid plaques since the disease was first described, their role in memory impairment has been poorly understood. Here, we show that reactive astrocytes aberrantly and abundantly produce the inhibitory gliotransmitter GABA by monoamine oxidase-B (Maob) and abnormally release GABA through the bestrophin 1 channel. In the dentate gyrus of mouse models of AD, the released GABA reduces spike probability of granule cells by acting on presynaptic GABA receptors. Suppressing GABA production or release from reactive astrocytes fully restores the impaired spike probability, synaptic plasticity, and learning and memory in the mice. In the postmortem brain of individuals with AD, astrocytic GABA and MAOB are significantly upregulated. We propose that selective inhibition of astrocytic GABA synthesis or release may serve as an effective therapeutic strategy for treating memory impairment in AD.

Pharmacologic treatment of apathy in dementia

Apathy in patients with dementia is common, underrecognized, and undertreated. We sought to improve understanding of the pharmacologic treatment of apathy in dementia by performing a systematic literature review of studies that used apathy outcome scales to document results of pharmacologic treatments for apathy. There is limited evidence of efficiency of pharmacotherapy for treatment of apathy in dementia. The best results were found for acetylcholinesterase inhibitors. There was some evidence of efficacy for memantine, but less evidence of efficacy for stimulants, calcium antagonists, and antipsychotics. There was no evidence to support the use of antidepressants or anticonvulsants. The research quality of studies was modest. Recommendations for standardizing research and for holistic evaluation and treatment are provided.

MAO-inhibitors in Parkinson's Disease

Monoamine oxidase inhibitors (MAO-I) belong to the earliest drugs tried in Parkinson's disease (PD). They have been used with or without levodopa (L-DOPA). Non-selective MAO-I due to their side-effect/adverse reaction profile, like tranylcypromine have limited use in the treatment of depression in PD, while selective, reversible MAO-A inhibitors are recommended due to their easier clinical handling. For the treatment of akinesia and motor fluctuations selective irreversible MAO-B inhibitors selegiline and rasagiline are recommended. They are safe and well tolerated at the recommended daily doses. Their main differences are related to (1) metabolism, (2) interaction with CYP-enzymes and (3) quantitative properties at the molecular biological/genetic level. Rasagiline is more potent in clinical practise and has a hypothesis driven more favourable side effect/adverse reaction profile due to its metabolism to aminoindan. Both selegiline and rasagiline have a neuroprotective and neurorestaurative potential. A head-to head clinical trial would be of utmost interest from both the clinical outcome and a hypothesis-driven point of view. Selegiline is available as tablet and melting tablet for PD and as transdermal selegiline for depression, while rasagiline is marketed as tablet for PD. In general, the clinical use of MAO-I nowadays is underestimated. There should be more efforts to evaluate their clinical potency as antidepressants and antidementive drugs in addition to the final proof of their disease-modifying potential. In line with this are recent innovative developments of MAO-I plus inhibition of acetylcholine esterase for Alzheimer's disease as well as combined MAO-I and iron chelation for PD.

Behavioral outcomes of monoamine oxidase deficiency: preclinical and clinical evidence

Monoamine oxidase (MAO) isoenzymes A and B are mitochondrial-bound proteins, catalyzing the oxidative deamination of monoamine neurotransmitters as well as xenobiotic amines. Although they derive from a common ancestral progenitor gene, are located at X-chromosome and display 70% structural identity, their substrate preference, regional distribution, and physiological role are divergent. In fact, while MAO-A has high affinity for serotonin and norepinephrine, MAO-B primarily serves the catabolism of 2-phenylethylamine (PEA) and contributes to the degradation of other trace amines and dopamine. Convergent lines of preclinical and clinical evidence indicate that variations in MAO enzymatic activity--due to either genetic or environmental factors--can exert a profound influence on behavioral regulation and play a role in the pathophysiology of a large spectrum of mental and neurodegenerative disorders, ranging from antisocial personality disorder to Parkinson's disease. Over the past few years, numerous advances have been made in our understanding of the phenotypical variations associated with genetic polymorphisms and mutations of the genes encoding for both isoenzymes. In particular, novel findings on the phenotypes of MAO-deficient mice are highlighting novel potential implications of both isoenzymes in a broad spectrum of mental disorders, ranging from autism and anxiety to impulse-control disorders and ADHD. These studies will lay the foundation for future research on the neurobiological and neurochemical bases of these pathological conditions, as well as the role of gene × environment interactions in the vulnerability to several mental disorders.

Therapy of depression in dementia

This is a comprehensive review of the existing diagnostic and treatment approaches to depression in Alzheimer's disease and related dementias. The existing evidence for the efficacy of pharmacological and nonpharmacological treatments are reviewed with an emphasis on the paucity of existing data and the need for more definitive controlled studies. In addition, data on the efficacy of such novel experimental treatments, such as various brain stimulation techniques (e.g., vagal nerve stimulation) are discussed. Alternative and psychosocial treatments are also reviewed.

Behavioral disinhibition and reduced anxiety-like behaviors in monoamine oxidase B-deficient mice

Monoamine oxidase (MAO) B catalyzes the degradation of beta-phenylethylamine (PEA), a trace amine neurotransmitter implicated in mood regulation. Although several studies have shown an association between low MAO B activity in platelets and behavioral disinhibition in humans, the nature of this relation remains undefined. To investigate the impact of MAO B deficiency on the emotional responses elicited by environmental cues, we tested MAO B knockout (KO) mice in a set of behavioral assays capturing different aspects of anxiety-related manifestations, such as the elevated plus maze, defensive withdrawal, marble burying, and hole board. Furthermore, MAO B KO mice were evaluated for their exploratory patterns in response to unfamiliar objects and risk-taking behaviors. In comparison with their wild-type (WT) littermates, MAO B KO mice exhibited significantly lower anxiety-like responses and shorter latency to engage in risk-taking behaviors and exploration of unfamiliar objects. To determine the neurobiological bases of the behavioral differences between WT and MAO B KO mice, we measured the brain-regional levels of PEA in both genotypes. Although PEA levels were significantly higher in all brain regions of MAO B KO in comparison with WT mice, the most remarkable increments were observed in the striatum and prefrontal cortex, two key regions for the regulation of behavioral disinhibition. However, no significant differences in transcript levels of PEA's selective receptor, trace amine-associated receptor 1 (TAAR1), were detected in either region. Taken together, these results suggest that MAO B deficiency may lead to behavioral disinhibition and decreased anxiety-like responses partially through regional increases of PEA levels.

Glyceraldehyde-3-phosphate dehydrogenase-monoamine oxidase B-mediated cell death-induced by ethanol is prevented by rasagiline and 1-R-aminoindan

The inhibitors of monoamine oxidase B (MAO B) are effectively used as therapeutic drugs for neuropsychiatric and neurodegenerative diseases. However, their mechanism of action is not clear, since the neuroprotective effect of MAO B inhibitors is associated with the blockage of glyceraldehyde-3-phosphate dehydrogenase (GAPDH)-death cascade, rather than the inhibition of MAO B. Here, we provide evidence that GAPDH potentiates the ethanol-induced activity of MAO B and brain cell toxicity. The levels of nuclear GAPDH and MAO B activity are significantly increased in brain-derived cell lines upon 75 mM ethanol-induced cell death. Over-expression of GAPDH in cells enhances ethanol-induced cell death, and also increases the ethanol-induced activation of MAO B. In contrast, the MAO B inhibitors rasagiline and selegiline (0.25 nM) and the rasagiline metabolite, 1-R-aminoindan (1 muM) decreases the ethanol-induced MAO B, prevents nuclear translocation of GAPDH and reduces cell death. In addition, GAPDH interacts with transforming growth factor-beta-inducible early gene (TIEG2), a transcriptional activator for MAO B, and this interaction is increased in the nucleus by ethanol but reduced by MAO B inhibitors and 1-R-aminoindan. Furthermore, silencing TIEG2 using RNAi significantly reduces GAPDH-induced MAO B upregulation and neurotoxicity. In summary, ethanol-induced cell death, attenuated by MAO B inhibitors, may result from disrupting the movement of GAPDH with the transcriptional activator into the nucleus and secondly inhibit MAO B gene expression. Thus, the neuroprotective effects of rasagiline or 1-R-aminoindan on ethanol-induced cell death mediated by a novel GAPDH-MAO B pathway may provide a new insight in the treatment of neurobiological diseases including alcohol-use disorders.

Comparative neuroprotective effects of rasagiline and aminoindan with selegiline on dexamethasone-induced brain cell apoptosis

Stress can affect the brain and lead to depression; however, the molecular pathogenesis is unclear. An association between stress and stress-induced hypersecretion of glucocorticoids occurs during stress. Dexamethasone (a synthetic glucocorticoid steroid) has been reported to induce apoptosis and increase the activity of monoamine oxidase (MAO) (Youdim et al. 1989). MAO is an enzyme for the degradation of aminergic neurotransmitters; dopamine, noradrenaline and serotonin and dietary amines and MAO inhibitors are classical antidepressant drugs. In this study, we have compared the ability of rasagiline (Azilect) and its main metabolite, R-aminoindan with selegiline (Deprenyl) in prevention of dexamethasone-induced brain cell death employing human neuroblastoma SH-SY5Y cells and glioblastoma 1242-MG cells. Dexamethasone reduced cell viability as measured by MTT test, but rasagiline, selegiline, and 1-R-aminoindan could significantly prevent dexamethasone-induced brain cell death. Among three drugs, rasagiline had the highest neuroprotective effect. Furthermore, the inhibitory effects of these drugs on MAO B catalytic activity and on apoptotic DNA damage (TUNEL staining) were examined. Rasagiline exhibited highest inhibition on MAO B enzymatic activity and prevention on DNA damage as compared to selegiline and 1-R-aminoindan. In summary, the greater neuroprotective effect of rasagiline may be associated with the combination of the parent drug and its metabolite 1-R-aminoindan.

Synergistic effects of selegiline and donepezil on cognitive impairment induced by amyloid beta (25-35)

Selegiline, an irreversible inhibitor of monoamine oxidase B used in the treatment of Parkinson's disease, has been demonstrated to have a potential cognition-improving effect in patients with Alzheimer's disease (AD) undergoing treatment with an acetylcholinesterase inhibitor donepezil. To confirm such clinical events, we investigated whether co-administration of donepezil with selegiline had a synergistic cognition-improving effect in an animal model of AD. Intracerebroventricular injection of amyloid beta protein fragment 25-35 [Abeta(25-35)] induced impairment of learning and memory in a Y-maze, novel object recognition and contextual fear conditioning tests. Either donepezil or selegiline alone improved the cognitive impairments in the Y-maze and conditioned fear learning tasks in Abeta(25-35)-injected mice, whereas donepezil, but not selegiline, failed to improve the impairment in a novel object recognition task. Co-administration of donepezil with selegiline, at doses that do not exert efficacy individually, significantly improved the deficits in all three tests, indicating a synergistic cognition-improving effect. These alleviating effects were antagonized by pretreatment with a muscarinic receptor antagonist scopolamine and a dopamine receptor antagonist haloperidol. These results suggest that selegiline potentiates the effect of donepezil on the cognitive impairment, and that the synergistic effect may be mediated through both the cholinergic and dopaminergic systems.

Chronic exposure of rats to cognition enhancing drugs produces a neuroplastic response identical to that obtained by complex environment rearing

Recent data suggest that Alzheimer's patients who discontinue treatment with cholinesterase inhibitors have a significantly delayed cognitive decline as compared to patients receiving placebo. Such observations suggest cholinesterase inhibitors to provide a disease-modifying effect as well as symptomatic relief and, moreover, that this benefit remains after drug withdrawal. Consistent with this suggestion, we now demonstrate that chronic administration of tacrine, nefiracetam, and deprenyl, drugs that augment cholinergic function, increases the basal frequency of dentate polysialylated neurons in a manner similar to the enhanced neuroplasticity achieved through complex environment rearing. While both drug-treated and complex environment reared animals continue to exhibit memory-associated activation of hippocampal polysialylated neurons, the magnitude is significantly reduced suggesting that such interventions induce a more robust memory pathway that can acquire and consolidate new information more efficiently. This hypothesis is supported by our findings of improved learning behavior and enhanced resistance to cholinergic deficits seen following either intervention. Furthermore, the level of enhancement of basal neuroplastic status achieved by either drug or environmental intervention correlates directly with improved spatial learning ability. As a combination of both interventions failed to further increase basal polysialylated cell frequency, complex environment rearing and chronic drug regimens most likely enhanced cognitive performance by the same mechanism(s). These findings suggest that improved memory-associated synaptic plasticity may be the fundamental mechanism underlying the disease modifying action of drugs such as cholinesterase inhibitors. Moreover, the molecular and cellular events underpinning neuroplastic responses are identified as novel targets in the search for interventive drug strategies for the treatment of neurodegenerative and neuropsychiatric disorders.

Effects of selegiline alone or with donepezil on memory impairment in rats

Selegiline, a monoamine oxidase-B inhibitor, is reported to improve memory and learning in dementia of Alzheimer's type. However, only a few studies have reported its use in animal models. Here, we evaluated the effects of selegiline only or its combined use with donepezil, a selective acetylcholinesterase inhibitor on memory impairment, using a Morris water maze. Selegiline dose-dependently attenuated ethylcholine aziridinium ion-induced memory impairment. Co-administration of selegiline and donepezil, at doses that do not exert efficacy individually, significantly ameliorated scopolamine+p-chlorophenylalanine-induced memory deficits. These results suggest that selegiline improves memory impairment mediated by the cholinergic system, and provide evidence of the usefulness of co-treatment with selegiline and donepezil for treating spatial deficits in dementia.

New Synthesis of Propargylic Amines from 2-(Bromomethyl)aziridines. Intermediacy of 3-Bromoazetidinium Salts

A new, efficient, and straightforward synthesis provides propargylamines in high overall yields (64-77%) by transformation of 1-(arylmethyl)-2-(bromomethyl)aziridines into N,N-di(arylmethyl)-N-(2-propynyl)amines via N-(2,3-dibromopropyl)amines and N-(2-bromo-2-propenyl)amines. The conversion of N-(2,3-dibromopropyl)amines into N-(2-bromo-2-propenyl)amines is based on a novel analogue of the Hofmann elimination. A Yamaguchi-Hirao alkylation, a Sonogashira coupling, or a hydroarylation reaction further functionalized these propargylamines toward potentially interesting compounds for medicinal and agrochemical use.

l-Deprenyl as an inhibitor of menadione-induced permeability transition in liver mitochondria

L-Deprenyl, an inhibitor of mitochondrial monoamine oxidase B (MAO B), inhibits the swelling of liver mitochondria induced by the pro-oxidant 2-methyl-1,4-naphtoquinone with a K(i) dependent on quinone concentration. L-Deprenyl also inhibits the collapse of membrane potential, cation efflux, pyridine nucleotide oxidation and cytochrome c release, all events which accompany the osmotic change and are typical of membrane permeability transition induction, thus emphasizing the inhibitory effect of the drug on this phenomenon. Results show that this inhibition is not due to the effect of L-deprenyl on monoamine oxidase activity but is most likely due to a direct interaction of the drug with the pore forming structures. It is here proposed that L-deprenyl, being a propargylamine, at physiological pH has a protonated amino group able to interact with critical aromatic or anionic amino acidic residues. As a consequence, the opening of the transition pore is prevented. These results indicate a more generalized protective effect of L-deprenyl on mitochondrial functions, involving the inhibition of membrane permeability transition induced not only by the oxidation of substrates of MAO B, but also by pro-oxidant agents such as 2-methyl-1,4-naphtoquinone, which does not involve MAO B activity.

Selegiline for Alzheimer's disease

BACKGROUND

Alzheimer's disease is the most common cause of dementia in older people accounting for some 60% of cases with late-onset cognitive deterioration. It is now thought that several neurotransmitter dysfunctions are involved from an early stage in the pathogenesis of Alzheimer's disease-associated cognitive decline. The efficacy of selegiline for symptoms of Alzheimer's disease remains controversial and is reflected by its low rate of prescription and the lack of approval by several regulatory authorities in Europe and elsewhere. Reasons for this uncertainty involve the modest overall effects observed in some trials, the lack of benefit observed in several trials, the use of cross-over designs which harbour methodological problems in a disease like dementia and the difficulty in interpreting results from trials when a variety of measurement scales are used to assess outcomes.

OBJECTIVES

The objective of this review is to assess whether or not selegiline improves the well-being of patients with Alzheimer's disease.

SEARCH STRATEGY

The Cochrane Dementia and Cognitive Impairment Group Register of Clinical Trials, was searched using the terms 'selegiline', 'l-deprenyl', "eldepryl" and "monamine oxidase inhibitor-B". MEDLINE, PsycLIT and EMBASE electronic databases were searched with the above terms in addition to using the group strategy (see group details) to limit the searches to randomised controlled trials.

SELECTION CRITERIA

All unconfounded, double-blind, randomised controlled trials in which treatment with selegiline was administered for more than a day and compared to placebo in patients with dementia.

DATA COLLECTION AND ANALYSIS

An individual patient data meta-analysis of selegiline, Wilcock 2002 provides much of the data that are available for this review. Seven studies provided individual patient data and this was pooled with summary statistics from the published papers of the other nine studies. Where possible, intention-to-treat data were used but usually the meta analyses were restricted to completers' data (data on people who completed the study).

MAIN RESULTS

There are 17 included trials. There were very few significant treatment effects and these were all in favour of selegiline; cognition at 4-6 weeks and 8-17 weeks, and activities of daily living at 4-6 weeks. There is little evidence of adverse effects caused by selegiline, and few withdrew from trials, apart from the Sano trial. The analyses were conducted on data available. There was no attempt to correct for missing patients because there were so few and withdrawal was probably unconnected with treatment. All trials examined the cognitive effects of selegiline, and in addition 12 trials examined the behavioural and mood effects. The meta-analysis revealed benefits on memory function, shown by improvement in the memory tests from several cognitive tests (the Randt Memory Index from Agnoli 1990 and Agnoli 1992, the BSRT from Sunderland 1992, prose recall from Filip 1991, ADAS-cog from Lawlor 1997, the Wechsler Memory Scale from Loeb 1990 and Mangoni 1991, the Rey -AVL from Piccinin 1990, and the MMSE from Sano 1995, Tariot 1998, Filip 1991, Freedman 1996, Burke 1993 and Riekkinen 1993). The combined memory tests, and overall the combined cognitive tests, analysed using standardised mean differences, showed an improvement due to selegiline compared with placebo at 4-6 weeks (SMD 0.39, 95%CI 0.07 to 0.72, P = 0.02, random effects model ) and 8-17 weeks, ( SMD 0.44, 95%CI 0.04 to 0.84, P = 0.03, random effects model). The meta-analyses of emotional state show no treatment effects. Several studies assessed activities of daily living using several different scales, the GBS-motor function from Agnoli 1990, the NOSIE-daily living from Filip 1991, the BDS-daily living from Loeb 1990 and Mangoni 1991, the DS from Sano 1995 and PIADL from Tariot 1998. The combined tests, analysed using the standardised mean difference, showed an improvement due to selegiline at 4-6 weeks (SMD -0.27, 95% CIs -0.41 to -0.13, P = <.001). The global rating scales, the BDS used by Burke 1993 and Tariot 1998, and the GBS used by Agnoli 1990 and Agnoli 1992, and the GDS used by Freedman 1996 and the CGI by Filip 1991, analysed using standardised mean differences showed no effect of selegiline. A variety of adverse effects were recorded, but very few patients left a trial as a direct result. Four studies reported no side effects. Mangoni 1991 reported poor tolerability for 3 patients out of 68 on treatment and 1 out of 51 on placebo, resulting in dropouts. Small numbers found equally in both groups reported anxiety, agitation, dizziness, nausea and dyspepsia. Piccinin 1990 reported that selegiline was well tolerated with few adverse reactions (dizziness and orthostatic hypotension) and no resulting drop outs. Burke 1993 and Loeb 1990 both reported that selegiline was very well tolerated with no serious side effects. Sano 1995 reported 49 categories of adverse events but found no differences between the 4 arms of the factorial trial. Freedman 1996 reported unequal numbers of dropouts in the trial with 7 subjects withdrawing from the selegiline group and only 1 subject from the placebo group. The meta-analyses of the numbers suffering adverse effects, and of the numbers of withdrawals before the end of the trial show no difference between control and selegiline.

REVIEWER'S CONCLUSIONS

Despite its initial promise, ie the potential neuroprotective properties, and its role in the treatment of Parkinson's disease sufferers, selegiline for Alzheimer's disease has proved disappointing. Although there is no evidence of a significant adverse event profile, there is also no evidence of a clinically meaningful benefit for Alzheimer's disease sufferers. This is true irrespective of the outcome measure evaluated, ie cognition, emotional state, activities of daily living, and global assessment, whether in the short, or longer term (up to 69 weeks), where this has been assessed. There would seem to be no justification, therefore, to use it in the treatment of people with Alzheimer's disease, nor for any further studies of its efficacy in Alzheimer's disease.

Comorbidity of depression with other medical diseases in the elderly

A major factor in the context of evaluating depression in the elderly is the role of medical problems. With aging there is a rapid increase in the prevalence of a number of medical disorders, including cancer, heart disease, Parkinson's disease, Alzheimer's disease, stroke, and arthritis. In this article, we hope to bring clarity to the definition of comorbidity and then discuss a number of medical disorders as they relate to depression. We evaluate medical comorbidity as a risk factor for depression as well as the converse, that is, depression as a risk factor for medical illness. Most of the disorders that we focus on occur in the elderly, with the exception of HIV infection. This review focuses exclusively on unipolar disorder. The review summarizes the current state of the art and also makes recommendations for future directions.

The effect of selegiline in the treatment of people with Alzheimer's disease: a meta-analysis of published trials

OBJECTIVE

To evaluate the effect of selegiline in the treatment of patients with Alzheimer's disease, in terms of cognitive performance, functional ability, emotional state (including behaviour and mood) and global response. Data Sources The Cochrane database of trials, Embase, Medline and Psychlit. Study Selection Unconfounded, double-blind, randomised trials of selegiline compared with placebo reported before 31 December 1998. Data Extraction The reviewers selected trials for inclusion. Individual patient data were sought, but when these could not be retrieved summary data were extracted from published papers.

RESULTS

Of 27 identified trials, 14 met the inclusion criteria. Individual patient data were retrieved from eight trials on 821 patients. Summary data were extracted from five trials on 240 patients. No data were available from one trial on 12 patients, which was therefore excluded from the meta-analysis. Fixed and random effects meta-analyses were performed on standardised mean differences. For cognition there was a statistically significant difference between selegiline and placebo at 4-6 weeks and 8-17 weeks after randomisation (at 8-17 weeks: smd=0.45 [95% confidence interval 0.03 to 0.88]), but this disappeared at later assessments. The size of the treatment difference was considered unlikely to be of clinical importance. Although there was a statistically significant difference at 4-6 weeks for activities of daily living, this disappeared at later assessments (at 8-17 weeks: smd=0.33 [-0.33, 0.69]). There were no statistically significant differences or clinically relevant differences between selegiline and placebo in terms of emotional state or global response.

CONCLUSION

Although there was some evidence of improvement with selegiline in the short term in cognition and activities of daily living, the magnitude of the effect did not reach clinical importance. There was no evidence of long term effects.

Clinical and economic factors in the treatment of behavioural and psychological symptoms of dementia

The prevalence of behavioural and psychological symptoms of dementia (BPSD) exceeds 50%. They cause distress to patients and caregivers, increase resource utilisation of various kinds, and form a high risk for accelerated psychiatric care through institutionalisation. Although evidence for current pharmacological treatment is not strong and the construct of BPSD is still not very clear, future aspects of treatment of BPSD may be positive. If we look at overall success rates of the antipsychotics, the traditional antipsychotics have the highest combined success rate of 63.1%, whereas the novel antipsychotics have an overall success rate of 56.1%. Haloperidol is the drug with the highest success rate of 65.4%, although this drug is associated with parkinsonian adverse drug reactions. Newer antipsychotics show promise in treating BPSD, but more convincing evidence (e.g. from randomised clinical trials) is required. We provide an overview of the clinical, epidemiological and economic aspects of BPSD and a review of the available literature on their pharmacological treatment. Although only 1 pharmacoeconomic study has been conducted on BPSD, it seems likely that these manifestations drastically increase the burden of dementia.

Antiaging compounds: (-)deprenyl (selegeline) and (-)1-(benzofuran-2-yl)-2-propylaminopentane, [(-)BPAP], a selective highly potent enhancer of the impulse propagation mediated release of catecholamine and serotonin in the brain

Hundreds of millions of people now die over the age of 80 years primarily due to twentieth century progress in hygiene, chemotherapy, and immunology. With a longer average lifespan, the need to improve quality of life during the latter decades is more compelling. "Aging--The Epidemic of the New Millenium," a recent international conference (Monte Carlo, June 17-18, 2000), showed with peculiar clarity that a safe and efficient drug strategy to slow the age-related decay of brain performance is still missing. This review summarizes the physiologic and pharmacologic arguments in favor of a peculiar lifelong prophylactic medication with reasonable chances to keep in check brain aging and decrease the precipitation of age-related neurological diseases.

Clinically significant depressive symptoms and very mild to mild dementia of the Alzheimer type

OBJECTIVE

To compare depressive symptoms reported by persons with very mild or mild dementia of the Alzheimer type (DAT) with those reported for the person by a collateral source.

DESIGN

Cross-sectional evaluation.

SETTING

Washington University Alzheimer's Disease Research Center.

PARTICIPANTS

Consecutive series of elderly volunteers (n = 156) enrolled in longitudinal studies with a Clinical Dementia Rating (CDR) of 0.5 (very mild) or 1 (mild). Twenty-one per cent (n = 33) exhibited clinically significant depressive symptoms for which treatment was recommended.

MAIN OUTCOME MEASURES

Presence and frequency of DSM-IV depressive symptoms within the last year and last month reported by the participant or collateral source as ascertained by clinical examination and structured interviews.

RESULTS

Collateral source information is essential in diagnosing clinically significant depressive symptoms. The Geriatric Depression Scale scores correlate with participant information only and therefore may substantially underestimate depression. Depressive symptoms fluctuate in individuals with DAT. The most consistent depressive symptoms are depressed mood, fatigue and indecision.

CONCLUSIONS

Clinically significant depressive symptoms may be common in individuals with very mild or mild DAT, although they may fluctuate. Information from both a knowledgeable collateral source and the participant is important for detection of depressive symptoms.

Recommendations for the management of behavioral and psychological symptoms of dementia

BACKGROUND

The behavioral and psychological symptoms of dementia (BPSD) are common, serious problems that impair the quality of life for both patient and caregiver. In order to provide recommendations based upon the best available evidence, a qualitative literature review was performed.

METHODS

A search of the English language medical literature published between 1966 and 2000 was performed. The quality of the studies was assessed by considering the subjects, trial design, analysis and results. Final recommendations were based upon the quality of available evidence.

RESULTS

The management of BPSD begins with a thorough assessment to search for underlying causes of behaviour change. Concomitant medical illness should be treated and sensory impairment ameliorated. Nonpharmacological approaches should be instituted prior to medication use. These interventions include music, light, changes in level of stimulation and specific behavioral techniques. Antipsychotics are the best studied pharmacological intervention for agitation and aggression and have demonstrated modest but consistent efficacy. Antidepressants such as trazodone and selective serotonin re-uptake inhibitors, as well as anticonvulsants such as carbamazepine and valproic acid have also demonstrated efficacy. Benzodiazepines can be used for short-term treatment as p.r.n. agents when necessary. Pharmacotherapy must be monitored closely for both effectiveness and side effects, with consideration of medication withdrawal when appropriate.

CONCLUSION

The management of BPSD can significantly improve the quality of life for the patient and caregiver. Their assessment and management are essential components of the treatment of dementia.

Depressive syndromes in dementia

BACKGROUND

Depressive syndromes in dementia are common, treatment is challenging and controlled intervention studies are small in number. The goal of this paper is to review known information about the etiology, epidemiology and treatment of these syndromes, as summarized at the recent Canadian Consensus Conference on Dementia.

METHODS

A number of Medline searches were performed (most recently updated in October 2000) using the subject categories dementia and depression, or apathy or emotional lability and other relevant articles were also reviewed. The background article was edited and amended at the Consensus Conference on Dementia. Final recommendations appearing in the summary article by Patterson et al were accepted by the group consensus process. Clinical discussion and informational updates were added for the current text by the authors.

RESULTS

Depressive syndromes, ranging in severity from isolated symptoms to full depressive disorders, increase in dementia. While clear-cut depressive disorder is increased in this population, sub-syndromal disorders are even more common and cause considerable distress. Antidepressant treatment may improve the quality of life in depressed, demented people, although it is less successful than in those without cognitive impairment and carries more risk of iatrogenic effects.

CONCLUSIONS

Physicians should be alert to the presence of depressive syndromes in dementia. Depressive illness should be treated and, when necessary, referral should be made to an appropriate specialist. Treatment must minimize iatrogenic effects. Although there is some support for treatment of syndromes that do not meet criteria for depressive disorder or dysthymia, the first line of intervention in these situations should involve nonpharmacological approaches.

Monoamine oxidase-B inhibitors in the treatment of Alzheimer's disease

The monoamine oxidase-B (MAO-B) inhibitor L-deprenyl (Selegiline) is effective in treating Parkinson's disease and possibly Alzheimer's disease, with a concomitant extension of life span. It has been suggested that the therapeutic efficacy of L-deprenyl may involve actions other than the inhibition of the enzyme MAO-B. This article reviews some novel actions of L-deprenyl and suggests that stimulation of nitric oxide (NO) production could be central to the action of the drug. L-Deprenyl induced rapid increases in NO production in brain tissue and cerebral blood vessels. In vitro or in vivo application of L-deprenyl produced vasodilatation. The drug also protected the vascular endothelium from the toxic effects of amyloid-beta peptide. Because NO modulates activities including cerebral blood flow and memory, and reduced NO production has been observed in AD brain, stimulation of NO production by L-deprenyl could contribute to the enhancement of cognitive function in AD. MAO-B inhibitors are unique in that they exert protective effects on both vascular and neuronal tissue and thus warrant further consideration in the treatment of vascular and neurodegenerative diseases associated with aging.

l-Deprenyl, blocking apoptosis and regulating gene expression in cultured retinal neurons

Apoptosis is the final pathway of many forms of retinal degeneration. E1A-NR3 is an immortalized retinal cell line that manifests specific phenotypes of retinal neurons. The present study induced apoptosis in these cells by two ischemic assaults, serum deprivation and hypoxia. The results demonstrated that both the assaults decreased viable cell numbers significantly by inducing apoptosis, as revealed by viable cell count, DNA fragmentation analysis, and in situ labeling of apoptotic cells by the TdT-mediated dUTP-biotin nick end-labeling (TUNEL) method. l-Deprenyl is known to be a monoamine oxidase inhibitor, and it was found recently to have neurotrophic activities. We set out to determine the protective effect of l-deprenyl on retinal cells and delineate its mechanism independent of monoamine oxidase inhibition. At concentrations as low as 0.0001 and 0.001 microM, l-deprenyl significantly increased the numbers of surviving cells under serum-free and hypoxic conditions, respectively. This effect appeared to be dependent upon the l-deprenyl concentration within the range of 0.001 to 10 microM. The neurotrophic activity was via blocking apoptosis, as l-deprenyl decreased the fragmented DNA and the numbers of positively stained apoptotic cells under serum-free or hypoxic conditions. Using mRNA differential display, nine mRNAs were identified and confirmed by northern blot analysis to have altered expression levels at 8 hr of exposure to hypoxia. Five of them do not match any existing sequences in GenBank, whereas the other four represent known genes including c-jun, heat-shock protein hsp70, phosphoglycerate kinase (PGK), and calpactin I heavy chain. All of the four mRNAs were increased significantly by hypoxia. The c-jun, PGK, and calpactin mRNAs, but not hsp70, also were increased by serum withdrawal. l-Deprenyl partially reversed the increase in c-jun and hsp70 mRNA levels, but not in PGK and calpactin. These results suggest that l-deprenyl blocks apoptosis induced by hypoxia as well as by growth factor withdrawal and regulates the expression of apoptosis-related genes.

Free radicals in Alzheimer's dementia: currently available therapeutic strategies

Substantial evidence now exists that oxidative stress may play an important role in the etiopathogenesis of DAT. The different sources of oxidative stress in DAT are suggesting several pharmacological opportunities for influencing the disease. It is possible to distinguish 2 major types of possible therapeutic agents according to their pharmacological point of attack. 1. Radical scavengers, agents directly interacting with free radicals. Candidates of this type are gingko biloba, vitamins A, C, E and estrogen. 2. Antioxidants, which are able to prevent or decrease the production of free radicals by use of specific neuropharmacological properties. Candidates are selegiline, a MAO-B inhibitor well established in the therapy of Parkinson's disease, and tenilsetam, which is believed to be an AGE-inhibitor. Recent in vitro studies have demonstrated the efficacy of both types of therapeutic agents by preventing or delaying oxidative neural damage. Some clinical data exist regarding the antidementive properties particularly in terms of gingko biloba, selegiline and vitamin E. The efficacy studies about these compounds seem to indicate a promising future strategy in the therapy of DAT. But it is too early to draw definite conclusions since it is well known that all of our candidate substances do not act specifically as radical scavengers or antioxidants.

(-)Deprenyl (selegiline), a catecholaminergic activity enhancer (CAE) substance acting in the brain

beta-Phenylethylamine and its long acting derivatives, the amphetamines, are mixed-acting stimulants of the sympathetic system in the brain. They enhance the impulse propagation mediated release of catecholamines (catecholaminergic activity enhancer effect) and displace catecholamines from their stores (catecholamine releasing effect). (-)Deprenyl (selegiline), a close structural relative to (-)methamphetamine, is the first catecholaminergic activity enhancer substance in clinical use devoid of catecholamine releasing property, being therefore free of the 'cheese effect' and of the dependence capacity of the amphetamines. (-)Deprenyl is also a highly potent and selective, irreversible inhibitor of monoamine oxidase type B. (-)Deprenyl enhances superoxide dismutase and catalase activity in the striatum, protects the nigrostriatal dopaminergic neurons against selective neurotoxins (6-hydroxy-dopamine, MPTP, 4-N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine) and prevents characteristic age-related morphological changes in the neurocytes of the substantia nigra. Maintenance of rats on (-)deprenyl during the postdevelopmental phase of their life slows the age-related decline of sexual and learning performances and prolongs life significantly. Patients with early, untreated Parkinson's disease maintained on (-)deprenyl need levodopa significantly later than their placebo-treated peers, and when on levodopa plus (-)deprenyl, they live significantly longer than patients on levodopa alone. In patients with moderately severe impairment from Alzheimer's disease, treatment with (-)deprenyl slows the progression of the disease. It may be supposed that a prophylactic low dose administration of a safe catecholaminergic activity enhancer substance during the postdevelopmental phase of life will slow the age-related decline of behavioral performances, delay natural death and decrease susceptibility to Parkinson's disease and Alzheimer's disease.

Biphasic and region-specific MAO-B response to aging in normal human brain

Variations of monoamine oxidases (MAO) A and B were studied during aging in 27 human subjects (age range 17-93 years) in 18 brain structures of temporal cortex, frontal gyrus, hippocampal formation, striatum, cerebellum, and brainstem. [3H]Ro41-1049 and [3H]lazabemide were used as selective radioligands to image and quantify MAO-A and MAO-B respectively by enzyme autoradiography. Postmortem delay or time of tissue storage did not affect MAO-A or MAO-B levels. There was, moreover, no evidence of sexual dimorphism. A marked age-related increase in MAO-B was observed in most structures. This increase started at the age of 50-60 years. Before this age, MAO-B levels were constant in all structures studied. MAO-B-rich senile plaques were observed in some cortical areas but they did not significantly influence the age-related MAO-B increase. Surprisingly, no age-related MAO-B changes were observed in the substantia nigra. In contrast to MAO-B, no clear age-related changes in MAO-A were observed, indicating an independent regulation of the two isoenzymes, also suggested by the cross-correlation analysis of these data.

Urinary excretion of deprenyl metabolites

(+)-Deprenyl metabolites in rat's urine, such as nordeprenyl. methamphetamine amphetamine and p-hydroxy. methamphetamine were identified by HPLC-MS. After oral administration of 10 mg of pure (-)- and (+)-deprenyl to human volunteers, their urine was analyzed by gas chromatography. The concentration of methamphetamine was found to be overwhelming in the case of the (-)-isomer, while amphetamine and methamphetamine were excreted in equal amounts when (+)-deprenyl was administered. The metabolic processes of deprenyl resulted in metabolites possessing different lipophilicity, as it has been shown by planar displacement chromatography.

Selegiline in treatment of behavioral and cognitive symptoms of Alzheimer disease

OBJECTIVE

To evaluate the effects of selegiline on behavioral and cognitive symptoms of patients with Alzheimer disease.

DATA SOURCES

An English-language MEDLINE search (1982-1995) was used to identify the review articles and human clinical trials discussed in this article.

STUDY SELECTION

Double- and single-blind and open-label trials were reviewed. Studies were also reviewed if selegiline was evaluated comparatively with other agents. Review articles were used for background information.

DATA EXTRACTION

Data were evaluated from human studies. Studies were critiqued on the basis of design, methodology, duration, sample size, and the degree to which neuropsychological tests used in each study were compared.

DATA SYNTHESIS

Selegiline is a selective, irreversible inhibitor of monoamine oxidase type B. Eight of 11 controlled trials showed selegiline had a positive effect on cognition (e.g., word fluency, delayed recall, total recall). Two of 5 controlled trials evaluating selegiline's effect on behavior (e.g., anxiety, tension, excitement, depression) showed a positive effect.

CONCLUSIONS

The role of selegiline remains to be determined by large well-controlled long-term clinical trials. Selegiline may be a useful agent in managing behavioral and cognitive symptomatology associated with Alzheimer disease. Given that the management of Alzheimer disease is symptomatic and no standard treatment exists, selegiline should be considered among the various options.

Differences in some behavioural effects of deprenyl and amphetamine enantiomers in rats

Effects of deprenyl and amphetamine enantiomers on different behavioural patterns were compared. Whereas (+)-amphetamine in doses of 1-3 mg/kg SC, (-)-amphetamine, and (+)-deprenyl in doses of 5-20 mg/kg SC increased the locomotor activity and the time the animals displayed stereotyped head movement, enhanced the acquisition of conditioned avoidance responses, and developed positive place preference conditioning, (-)-deprenyl, even in as high a dose as 20 mg/kg SC, failed to show any amphetamine-type behavioural effect. The results provide further proof why (-)-deprenyl, in contrast to other members of the amphetamine family, can be considered as a safe drug.

Premorbid History of Major Depression and the Depressive Syndrome of Alzheimer's Disease

To test the hypothesis that primary degenerative dementia of the Alzheimer type (PDD-AT) may increase the likelihood of expression of a lifetime vulnerability to the development of depression, the authors compared the premorbid rates of major depression in psychiatric inpatients with dementia, with or without a concurrent syndrome of depression. A premorbid history of major depression was four times more common in patients with the depressive syndrome of PDD-AT than in PDD-AT patients without depression. The authors discuss the significance of these findings for pathophysiologic models and estimates of comorbidity of depression in PDD-AT.