Haloperidol treatment of behavioral disturbances in alzheimer patients

FOURTH INTERNATIONAL CONFERENCE ON ALZHEIMER’S DISEASE

confirmed electron microscopic examination the extracellular deposition of amyloid and the presence of SOme macrophages amyloid within many macrophages. containing amyloid were identified in sites distant from infusion. Although reactive the targeted areas of astrocytic hyperplasia was also evident, amyloid was not identified within astrocytes. Neuritic abnormalities were not well established after two weeks of infusion of beta neurofibrillary tangles amyloid peptide into rat brain: and neuritic plaques were not see" and degenerating axone were only occasionally noted at the ultrastructural level. The response to the infusion of beta amyloid peptide into rat brain involves both cellular and humeral components of the immune system and the macrophage appears to play a very important role in the processing and degradation of the infused beta amyloid.

THERAPEUTIC STRATEGIES I

S81

cells. The ratio hetwexx concentration of tacrine in :%sma and CSF varied between 0.1-0.7 and increased with increasing dose. Patients with high plasma /CSF ratios showed best clinical improvement The patients were continously evaluated regarding cognitive function and functional brain activity. These studies included EEG and positron emission tomography (PET) measuring cerebral glucose metabolism, blood flow, nicotinic and muscatinic receptors. After short-term treatments improvement in neuro- pychological performances was observed which paralleled increases in mean frequency of EEG and nicotinic receptors in cortical brain areas. Cerebral glucose metabolism was improved after several months of treatment and remained in some patients unchanged during 1-2 years of treatment. Increases in the dally dose of tacrlne from 80 mg to 120 or 160 mg were reflected in improvement in cognitive tests, EEG and nicotinlc receptors. It is apparent that long-term positive effects can he reached with tacrine which slow down the progression of Alzheimer disease To achieve beneficial effects of tactine it is important to focus on responders to the therapy. Most significant effects will likely be obtained when the treatment is initiated early in the course of the disease and continued for several months of treatment with adjustment of dose according to clinical outcome and side effects.

331

333

THE EFFECTS OF TACRINE IN PATIENTS WITH MILD VERSUS MODERATE STAGE ALZHEIMER’S DISEASE

TRANSDERMAL NICOTINE ADMINISTRATlON IN -R’S DISEASE: EFFECTS ON COGNITION, BEHAVIOR. AND CARDIAC FUNCTION. AL Wilson, JR McCarten, LK Langley, TB Batter. Gerlatr. Res. Educ. CUn. Ctr., VAMC. and Depts. of Neurology, Psychiatry, and Psychology, University of Minnesota, Minneapoiis. Minne.sota,55417 U.S.A. RATIONALE: Tire weB-establisbed cboIlnex&? defidt in Alzhefmer’s disease (AD) has been the focus of many drug trials. but results generaBy have been disappointing. Most trials have focused on muscarinic rather than nieotinic cbolinergic systems. Nicotintc receptors are deBdent in the AD brain and, unlike muscarinlc receptors, demonstrate upregulaUon with stimulation. la studies with nonhumans, normal humans, and patients wBb AD, acute nicotine administration improves performance on II variety of measures. The effects of cbronIc nicotine admlnIstmtton in AD have not been assess& METHODS: Six nonsmoking AD patients were enrolled in the witbin-subject A-B-A double-blind design inpatient protocol. Placebo or nicotine, 22mg. was administered vls a transdermsi patch applied daily for 7. 8. and 7 daye during baseline. treatment. and washout, respectively. Cognitive function was asses& with a delayed-match-to-sample task (DMTS) and a repeated acquisition task, tested daily, and the Dementia Rattng Scale (DRS), tested weekiy. Behavior In 14 categories was unobtrusively recorded for 45 mlautes each day. Rest/activity patterns were measured using a wrist-worn actlvlty monhof. Cardiac paratneters were assessed with 24 hour Holter monitoring. Blood levels of nicotine and its major metabolite. coUrttoe.were monRore4Ithroughout the protocol. RESULTS: Group data demonstrated a significantdecreasein leamlng errors on the repeated aquisltlon task during nicotine admInIstraUon (RMANOVA. pcO.05). with four of six patients improving. There was no slgultlcant group effect on the DOTS or the DRS. Behavioral observattons revealed an increase in time engaged In an actlvlty (in contrast tn just dttlng) for five of six patients. However, three patterns became less compliant with testing while on nicotine. Activity monitoring revealed a signliicant decrease in sleep at night during nlwtlne admtnIstraUon (Wllwxon test, pcO.05). but no effect on sleep during the day. Three subjects tolerated Halter monitoring. AI1 had mild increases In heart rate and ectopy but no signltlcant signs of iscbemia. Absorption of nicotine was variable with peak blood levels ranging from 3.9 tu I L7ngAnI. Patients reported very little nausea or other untoward symptoms. DISCUSSION: Our results suggest that transdennal niwtine may improve some aspects of cognitive function in patients with AD. On the other hart& some aspects of behavior may be adversely affected. Patients tended to be awake more at night and. while more engaged in activiUes, some were less wmplisnt and directable while on nicotine. In general. nlwtine appears safe and well-tolerated in this population, producing only mild cardiac changes and few systemic symptoms. Further study under a long-term protocol of administration appears warranted.

M. Farlow, A. Brashear, S. Hui and the Tacrine Study Group Hvoothesis: Tacrine has greater efficacy in patients with earlier stage Alzheimer’s disease (AD). &&I& Data from a large (N=263 evaluable patients) multi-center, parallel group, double blind, placebo controlled, 30-week trial involving dosages of tacrine up to 160 (mgday) were reanalyzed. Patients were selected by disease stage according to Mini Mental Status Exam score into high MMSE (18-26) and low MMSE (10-I 7) groups. The Alzheimer’s Disease Assessment Scale cognitive component (ADAS) and clinician- and caregiver-based global assessments were dependent variables. &t&s: Evaluable patients in the high and low MMSE groups on tacrine at 30 weeks had comparable levels of change in ADAS cog with -2.31 and -1 Sl point improvements from baseline respectively. However, the high MMSE placebo group at 30 weeks worsened by only .73 points, whereas the low MMSE placebo group worsened by 3.46 points. The high MMSE tacrine versus placebo difference at 30 weeks was 3.04 points, whereas, the low MMSE group difference was 4.97 points in favor of tacrine. A comparable pattern of change was seen in the global assessments. Interaction of MMSE level on treatment effect was borderline significant (p =.09). Conclusion: The initial hypothesis was not supported. Comparable levels of improvement were seen in cognitive function and global assessments in patients treated with tacrine with early and moderate stage AD. It is of interest that patients with lower MMSE scores on placebo appear to deteriorate more than higher MMSE patients. For this reason, there is a strong trend for greater treatment effects in moderately affected patients with AD.

332 LONG-TERM TREATMENT WITH TACRINE DELAYS PROGRESSION OF ALZHBIMER’S DISEASE AS DETERMINED BY COGNITIVE TESTS, EEG AND PET. A.Nordberg, Department of Clinical Neuroscience and Family Medicine, Geriatric Section and Center for Nicotine Research, Karolinska Institute, Huddinge Hospital B56, S-141 86 Huddinge. Sweden. The clinical effects of tacrine in Alzheimer patients is related to dose and lenghts of tacrine treatment We have now carefully followed eight Alrheimer patients treated with tacrine during 6 to 42 months in doses varying between 80 and 160 mg daily. The pharmakokinetic properties for tacrine and its main metabolites were continously recorded.When the tacrine dose was kept unchanged the plasma concentration remained constant for months and correlated positively to inhibition of acetylcholinesterase activity in red blood

334 HALOPERIDOL TREATMENT OF BEHAVIORAL DISTURBANCES IN ALZHEIMER PATIENTS. M.W. Dysken, S.S. Skare, L. Holden, and G. Vatassery. Geriatric Research, Education, and Clinical Center (GRECC), Minneapolis Veterans Administration Medical Center, One Veterans Drive, Minneapolis, MN 65417, USA. We examined the relationship between clinical improvement and blood levels of haloperidol in Alzheimer patients with behavioral problems. A total of 29 Alzheimer inpatients were evaluated for behavioral problems after at least a three day drug-free period. Patienta were assigned to one of three tixed oral dosages of haloperidol(O.5, 1.0, or 2.0 mg at 9AM and SPM) for the 6rst three weeks of drug treatment. Behavior ratings and blood samples were collected at SAM at

FOURTH INTERNATIONAL CONFERENCE ON ALZHEIMER’S DISEASE

the end of weeks 1,2, and 3 of haloperidol treatment. Baseline behavior ratings (BEHAVE-AD)indicated that 97% of patients had activity disturbances, 97% had aggressiveness, 62% had anxieties and phobias, 62% had paranoid and delusional ideation, 59% had diurnal rhythm disturbances, 28% had affective disturbances, and 17% had hallucinations. Although no significant correlations were apparent between clinical improvement (% change BEHAVE-AD) and blood levels of haloperidol, a good response (2 30% improvement) was observed in 55% of the patients who entered the study, At the end of the third week of treatment, these patients had plasma haloperidol levels ranging from 0.3 to 1.8 &ml and red blood cell haloperidol levels ranging from 0.3 to 1.9 ng/ml. Future studies with slightly higher and lower dosages of haloperidol will be used to further define the optimal blood level range for maximal treatment benefit.

induce hypettrophy of the surviving cholinergic neurons and not a replacement therapy. By attenuating the rate of degeneration and improving the function of the remaining choliuergic cells, it is expected to ameliorate the symptomatic behavioral

changes

which

arc due to the cholinergic

deficit.

Limited

clinical

trials

have been initiated with encouraging result. Biotechuically engineered pluripotent growth factors or combinations of factors, possibly including the NGF relatives neurotrophin-3 and neurotrophiu-4/5, may be necessary to obtain optimal behavioral effects.

POSTER SESSION III APP Biology

335 EXPERIMENTAL

TROPHIC

PHENOTYPE

THERAPY.

PROTECTION

OF

CHOLlNERGlC

337

ANDCORTICALSYNAPTICREMODELLING.

A. Claudia

Cuello,

Department

of Pharmacology&Therapeutics,

McGill

University,

Montreal,

AGGREGATION OF ENDOGENOUS SECRETED AMYLOID BETA PEPTIDE (Ap) INTO SDS-STABLE MULTIMERS. M.B. Podlisny, E. Koo,

Quebec,

Canada. NGF phenotype

and some in

Experimental beyond

evidence

would

choline

infarctions. neocortex.

Thus.

cholinergic

microscopic

could

in CNS,

of cortically

NGF

injured

(1992)

results

Natl.

an

functional treated therapy

A.C.,

(1993)

Acad.

Sci.,

with

high

cortical

demonstrates

remodelling”

in the

These

a doseand

unilateral

of the

number

of presynaptic NGF.

injury. actions

provokes activity

analysis

and behavioural

cortical

boutons.

These

changes

observed

observations

will

be

rn AD.

Progr. USA.,

Neuroscience, 57(l): 21-40; Garofalo, Neurol., (in press). (1993)

image

increase

and hypertrophy

animals

NGF

of rats bearing with

cholinergic

can have

enzymatic

by a “synaptic

in

CNS following

factors

Thus,

studies combined

of a possible

Cuello, Proc.

cortex

are accompanied

therapy

to protect animals

neurotrophic

phenotype.

the remarkable

in the context

adult

acetyltransferase

and synapses

explain

References: L. &al.,

changes

of

that

in the remaining

varicosities

changes

indicate

of choline

uptake

Electron

have been shown

neurons

of cbolinergic

up-regulation

that these biochemical

discussed

neurotrophins forebrain

the maintenance

dependent affinity

some

Br.

Res.,

98: 265-277;

Garofalo,

89: 2639-2643;

Garofalo,

L.

A.C.,

and Cuello,

L. etal.,

(1994)

Expl

Acknowledeements: Medical Research Council of Canada (MRC)

336 NEUROTROPHIC FACTOR THERAPY OF ALZHEIMER’S DISEASE. F. Hefti. Dept. of Neuroscience, Genentech. Inc., South San Francisco, CA 94080 Neurotrophic factors are important for development and maintenance of function of the adult nervous system. Administration of neurotrophic factors can attenuate age-related and experimentally induced degeneration and behavioral deficits in experimental animals, suggesting that these molecules may become important in the treatment of neurodegeneration. Among the best characterized neurotrophtc factors are NGF, which may be useful in the treatment of peripheral sensory neuropathy and Alzheimer’s disease, and CNTF, which may be beneficial in ALS. Effective neumtroohic factors have recently been discovered for douaminereic neurons and motorue~rons. Various strategiescan be pursued to develop thera&eutically aoolicable molecules which mimic neurotrouhic factor actions or stimulate their production or receptor mechanisms. In Alaheimer’s disease, there is region-specific loss of neuronal populations, particularly in areas connected to the hippocampus. Strongly affected are hippo&pal inputs from the entorhinal cortex, the cholinereic basal forebrain and the noradtenereic lccus cceruleus. The extent of the chol6ergic deficit, which is one of the earlTestchanges in AD, correlates well with the degree of memory impairment observed in individual patients. NGF is necessary for normal development of forebrain cholinergic neurons and these cells respond to NGF not only during development but throughout their entire lifespan. There am deIlcits in cholinergic systems in mutant mice lackiug functioual NGF genes. Animal experiments indicate that NGF preventscholinergic degeneration asauciated withnormalagingor withneuronalinjury.Jnadultrats withtransections of theaepto-hippccampal pathways,NGF administration

reverses degenerative changes of the choliuergic celI bodies. NGF treatment also iucreases the function of presynaptic cholinergic terminals, prevents postsynaptic cholinergic receptor supersensitivity, and improves the behavioral performance of partially lesioned or selected behaviorally impaired aged rats. Similar findings have been obtained in primates. The cause of the cholmergic decline in AD remains to be identified. NGF levels am normalin AD brains,however,anyotherstepin NGF relatedmechanisms couldbe compromised. The animalstudies suggest that NGF administration will

counteract cholinergic atrophy, irrespective of the actual cause. Thus, administration of NGF to AD patients represents a pharmacologic attempt to

S. Squazzo, D.B. Teplow and D.J. Selkoe. Center for Neurologic Diseases, Harvard Med. Sch. & Brigham & Women’s Hosp., Boston, MA 02115 USA. Extensive studies with synthetic Ag peptides have demonstrated that 1) peptide length and concentration are critical to the aggregation state of Ag; 2) the association of exogenous proteins or metals can affect the aggregation of Ag; and 3) aggregated Ag, but not soluble monomeric Ag. can be directly and/or indirectly toxic to neurons in culture. Because soluble Ag is constitutively secreted by normal cells in viva and in vim , and because aggregated, polymeric Ag is deposited in the cortex and blood vessels in AD, we looked for evidence of aggregation of endogenous secreted Ag under physiological conditions in culture. CHO cells transfected with PAP451 (either wildtype or mutant) that expressed high levels of gAPP were metabolically labeled overnight. The conditioned media (CM) were then immuno recipitated with Rl280 (raised to synthetic Agt.40) and electrophoresed in d DS-tncme ‘. gels. Autoradiography revealed the expected intense bands at 4 kD (A@ and 3 kD (p3), plus weaker bands at -6, 8 and 12 kD. All of these bands were also immunoprecipitated by other Afi antisera and were fully absorbable by synthetic Ag peptide. Antisera to 8APP regions flanking A8 did not precipitate these bands. 3H-phenylalanine radiosequencing of the gel-purified 8 kD band showed phenylalanines at positions 4, 19 and 20, directly confirming its identity as an Ag multimer (presumably a dimer). Additional phenylalanine peaks consistent with an Ag species beginning at arg 5 were also found in this band. To examine the possibility that the Ag aggregation occurred during immunoprecipitation or sample boiling in SDS, the precipitated samples were eluted from Protein A-sepharose with glycine and electrophoresed without heating; in this case, the same multimers were observed. Moreover, the same immunoprecipitation protocol failed to precipitate mummers of either synthetic Agt.40 [at a concentration (5 nM) similar to that of endogenous Ap] or endogenous A!.3from high Ag-secreting 293 cells transfected with gAPPg95. Prolonged incubation of CHO75I CM at 37’ led to increased aggregation of endogenous Ag. In conclusion, SDS-stable multimers of endogenous Ag form spontaneously in tissue culture media. This system can be used to examine factors which regulate aggregation of heterogeneous Ag peptides secreted by living cells at nanomolar concentrations, thus avoiding the concerns of studies of a single Ag synthetic peptide of defined length incubated at high doses under non-physiological conditions.

338 THE INHIBITORY EFFECT OF /3-AWYLOID PEPTIDE ON RAT BRAIN NAJCA EXCHANGE. Anfan Wu and Robert A. Colvin. Dept. Biological Sciences, Ohio University College of Osteopathic Medicine, Athens, OH 45701 USA. These studies were performed to determine the effect of addition of Alaheimer’s disease fl-amyloid peptide (#-AP) on Nat/Cal+ exchange activity. disease (AD) is characterized by certain Alzheimerrs

neuropathological lesions, including deposition of @AP, however, its pathogenic role is still not clear. Na+/Ca'+ exchange activity was measured in plasma membrane vesicles (PWV) purified from rat brain. The effect of synthetic peptide ~+IP~~ and scrambled (#AP,) were examined. PMV were preincubated with each peptide for 15 minutes(37°C) in buffer containing 137 arM NaCl, 10 mW HEPES(pH 7.4), and protease inhibitors. Ca'+ uptake was initiated by diluting PWv 20 fold with buffer containing either 137 mW NaCl or 137 mW cholinecl and %aCl. Caz* uptake was terminated by addition of 5 IUW LaCl, and rapid filtration. S-J%%35 inhibited Nai*-dependent Cat* uptake with an ICso of 800