Azza Ghali et al.

321

Study of Cerebrospinal Fluid Tissue Transglutaminase,

T-TAU, Amyloid Β42

in Alzheimer’s Disease

Azza A Ghali1, Manal El Batch

1, Wafaa Ibrahim

2, Gihan Farouk

3

Departments of Neuropsychiatry1, Medical Biochemistry

2, Clinical Pathology

3, Tanta University

ABSTRACT

Biochemical markers for Alzheimer disease would be of great value, especially to help in early diagnosis of the disease.

The current study has focused on three candidates that have been suggested to be indulged in the pathogenesis of

Alzheimer’ disease (AD): Tissue transglutaminase (tTG) activity, β-amyloid42 (Aβ 42) and total T-tau (T-tau). The study

included 15 patients with probable AD, 15 patients with probable vascular dementia (VaD) in addition to 10 control

subjects without neuropsychiatric diseases. The results of this study revealed that the CSF levels of total T-tau and

activity of tTG, were significantly higher in patients with AD when compared with VaD and control. Also, CSF Aβ42 of

patients with Alzheimer’s disease were significantly low when compared with vascular dementia, and controls. The

sensitivity and specificity of CSF T-tau and Aβ42 were found to be high for differentiation of AD patients from controls,

but their specificity against (VaD) is moderate. So, measurement of CSF tTG, T-tau and Aβ42 level in AD patients may

provide useful and relatively simple biochemical tests for differentiating Alzheimer’s Disease from vascular dementia .In

addition, the diagnostic usefulness of the CSF content of both T-tau and Aβ42 is superior to either measure alone with

high sensitivity and specificity for prediction of AD, and can be recommended as an aid to evaluate individuals

suspected of having dementia. (Egypt J. Neurol. Psychiat. Neurosurg., 2006, 43(2): 321-330)

INTRODUCTION

Alzheimer's disease (AD) is the most

common form of dementia that affects men and

women equally, and characterized by progressive

deterioration of cognitive functions such as

memory, and language and visuospatial

orientation. Associated symptoms are mood and

behavioral changes. The prognosis is poor with no

cure is available1,2

.

Underlying neuropathological changes in

AD are the accumulation of senile plaques (SPs)

and neurofibrillary tangles (NFTs). SPs are made

up mainly of β-amyloid, especially the 42-amino-

acid isoform, β-amyloid42 (Aβ42).The major

constituent of NFTs is a cytoskeleton-associated

protein called T-tau, which is

hyperphosphorylated in NFTs3. During the

progression of AD a substantial amount of

neurons degenerate in the brain. The mechanisms

of cell death involved in AD have not been fully

elucidated.

Amyloid β(Aβ) is the major constituent of

the characteristic SPs and cerebrovascular

amyloid found in the brains of AD patients. Aβ42

is proteolytically derived from Aβ42 precursor

protein (APP). APP may normally be involved in

cell adhesion related to synaptic maintenance.

Loss of synapses correlates with dementia,

suggesting that synaptic deficits may underlie

AD4. The major products of this proteolytic

cleavage process contain either 40 or 42 residues

(Aβ40 or Aβ42). Aβ42 is continuously produced in a

soluble form and is found in CSF suggesting that

its production and secretion are part of a

physiological process5. Overproduction of Aβ40-42

or failure to clear this peptide leads to AD,

through amyloid deposition associated with cell

death6.

The microtubule-associated protein, T-tau, is

a normal human brain phosphoprotein, which

Egypt J. Neurol. Psychiat. Neurosurg. Vol. 43 (2) - July 2006

322

binds to microtubules in the neuronal axons,

thereby promoting microtubule assembly and

stability7. Both normal and hyperphosphorylated

T-tau are dispersed to the CSF .T-tau is an in vitro

tTG substrate, being cross-linked and/or

polyaminated, the cross linked filamentous

aggregates of T-tau were insoluble, suggesting

that this may be a contributing step in the process

leading to the formation of NFTs8. The Glutamine

and Lysine residues in T-tau that are modified by

tTG in vitro are located primarily within or

adjacent to the microtubule-binding domains9. If

tTG is involved in T-tau aggregation and NFTs

formation, it can be hypothesized that tTG activity

and/or expression may be elevated in AD8.

Tissue transglutaminase (tTG) (EC 2.3.2.13)

is a multifunctional protein that is likely to play a

role in numerous processes in the nervous system.

tTG post-translationally modifies proteins by trans-

amidation of specific polypeptide bound

glutamines. This action results in the formation of

protein cross links or the incorporation of

polyamines into substrate proteins, modifications

that likely have significant effects on neural

function10,11

. At first the proteasome machinery can

recognize and degrade the cross-linked proteins, but

over time the proteasome machinery may be

overwhelmed and protein aggregates will

accumulate12,13

. It was suggested that the protein

polymers resulting from tTG-catalyzed reactions

may play a role in commitment of cells to undergo

apoptosis14,15

. The most ubiquitously expressed

member of the TGase family, known as tissue

TGase (tTG) or TG2, which catalyzes the

production of epsilon-lysine to gamma-glutaminyl

isodipeptide bonds. It differs from other members

of the TGase gene family in this regard and may

implicate it in 'switches' from life or trophic

signaling to those associated with apoptosis. In this

regard, recent data indicate that one or more

TGases are involved in neurodegenerative disorders

such as Alzheimer's and Parkinson's diseases16

. As

do many genes, particularly those highly expressed

in the CNS, tTG undergoes alternative processing.

Elevated expression and alternative splicing,

resulting in a short (S) isoform of tTG with more

active cross-linking activity, are associated with

increased neuronal loss in affected regions in the

demented brain12

. An increase in tTG protein level

is found in postmortem AD brains as well as in

Huntington's disease17

. Many polypeptides

associated with neurodegenerative diseases are

suggested to be putative transglutaminase substrates

such as beta amyloid protein of Alzheimer's

disease, microtubule-associated proteins and

neurofilaments18

.

An analysis of symptoms and signs, blood

studies and brain imaging are major ingredients of

the clinical diagnostic work-up. However, the

diagnosis based on these instruments is

unsatisfactory, indicating the need of highly

sensitive and reliable approaches, selective for

AD and based on biological markers6. Therefore

genetic and/or biochemical markers that support

the clinical diagnosis and can distinguish AD from

cognitive symptoms attributable to ageing and

from other dementias will be of great value. The

identification of such accurate markers for the

early diagnosis of AD is mandatory for the

development of efficient pharmacological

treatment, since therapy should be initiated at an

early stage of the disease, before extensive and

irreversible brain damage has occurred6,19

. As the

intercellular space in the brain is in direct contact

with the CSF, biochemical changes in the brain

may be reflected by CSF analyses that should

reflect the patho-physiological mechanisms of

AD20

. So, the aim of the current study is to assess

CSF changes in tissue transglutaminase activity,

T-tau and Aβ42 in AD and VaD patients. Also, to

determine the sensitivity and specificity of T-tau

and Aβ42 combination as predictors of AD and its

severity.

SUBJECTS AND METHODS

This study included 3 groups of matched

age: AD group comprised of 15 patients with the

clinical diagnosis of “probable AD”, 15 patients

with the clinical diagnosis of “probable” vascular

dementia (VaD), and The healthy control group

consisted of 10 subjects. Control subjects were

Azza Ghali et al.

323

undergoing spinal anesthesia for orthopedic

surgery, without histories, symptoms, or signs of

psychiatric or neurological disease, malignant

disease, or systemic disorders (for example,

rheumatoid arthritis, infectious disease). No

subject had cognitive symptoms.

All subjects underwent a comprehensive

clinical evaluation including medical history,

physical, neurological, and psychiatric

examinations. The presence or absence of

dementia was diagnosed according to the

Diagnostic and Statistical Manual of mental

Disorders, fourth edition (DSM IV) criteria21

.

Probable AD was diagnosed according to the

National Institute of Neurological and

Communicative Disorders and Stroke-Alzheimer

disease and Related Disorders (NINCDS-ARDA)

criteria22

. The minimental state examination

(MMSE) was used to judge the severity of the

dementia. Probable Vascular Dementia was

diagnosed by the Hachinski Ischemic Scale

(HIS)23

, and according to National Institute of

Neurological Diseases and Stroke-Association

International pour La Rechache et l Enseigment en

Neuroscience (NINDS-AIREN) criteria24

. Mixture

forms (AD plus) were interpreted as AD

according to Bonelli et al.16

.

Patients with probable AD had insidious

onset and even progressive dementia which could

not explained by systemic or brain disorders other

than A.D. No patients had prominent frontal lobe

symptoms or history, clinical, or brain imaging

signs of cerebrovascular diseases. Patients with

probable AD were classified into mild AD

(MMSE score > 14) and severe AD (MMSE score

< 14). Probable vascular dementia was diagnosed

in patients with history of transitory ischemic

attacks or stroke episodes with temporal relation

to the development of dementia; together with CT

and/or MRI findings of lacunes, infarcts, or white

matter lesions. Other forms of dementia (e.g.,

Huntington, disease, progressive supranuclear

palsy) were excluded in this study.

Routine laboratory tests, EEG, and brain

MRI were done. All subjects underwent lumbar

puncture for diagnostic reasons after they gave

informed consent and undergo CSF analyses.

After centrifugation to eliminate cells and other

insoluble material, all CSF samples were frozen at

-70oC pending biochemical analyses. 1) CSF-T-

tau was determined using a sandwich ELISA

(BioSource, International, Inc.), constructed to

measure total T-tau (both normal T-tau and

phosphorylated -T-tau), as described previously in

accordance with the manufacturer’s instructions25

,

2) CSF Aβ42 was determined using a sandwich

ELISA(Immuno Biological Laboratories) as

described by Mehta et al.26

, 3)CSF tTG activity

was determined according to De Macedo et al.27

,

and CSF protein was determined according to

modified Lowry et al.28

using bovine albumin as a

stander. The enzyme activity was expressed as

anilide umol/min/mg protein.

Statistical analysis: results were expressed

as the mean±SD. Mean of different groups was

compared using a one-way analysis of variance

(ANOVA) followed by Student-Newman-Keuls

test. P<0.05 was accepted as significant.

Correlation between variables was evaluated using

Pearson’s correlation coefficient. Cut-off point of

T-tau and Aβ42 was determined according to

Andreasen et al.29,30

.

RESULTS

Analyses of the results:

Table (1) shows the clinical characteristics

of studied groups in which neither the age nor the

duration of dementia significantly differ between

AD, VaD and control, but, the mean MMSE score

showed significant difference between the studied

groups. The mean values of CSF biomarkers in

each group studied have been shown (Table 2).

The highest significant values of CSF T-tau and

tTG activity were observed in the two AD

subgroups as compared with both control and

VaD, while the lowest significant values of Aβ42

were found in severe AD as compared with both

control and VaD. No significant correlation was

found in the AD group, between CSF changes in

tTG activity, T-tau protein, Aβ42 and either age,

severity or duration of the disease (Table 2). An

Egypt J. Neurol. Psychiat. Neurosurg. Vol. 43 (2) - July 2006

324

inverse correlation was found between CSF

concentrations of T-tau and Aβ42 within the AD

group. No significant correlation was found

between tTG activity and both T-tau and Aβ42.

Using a cut-off point of T-tau =306(pg/ml) and

Aβ42=500(pg/ml), the sensitivity and specificity of

CSF-T-tau and Aβ42 was calculated as diagnostic

markers for AD. The sensitivity was defined as

the ability of CSF-T-tau and Aβ42 to identify AD.

The specificity was defined as the ability of CSF-

T-tau and Aβ42 to exclude AD, whereas the

positive predictive value was defined as the

proportion of correctly diagnosed patients with

AD of all patients with high CSF-T-tau and low

Aβ42 (Altman et al., 1983). 9/10 (90%) of the

controls had normal levels of both CSF-T-tau and

CSF-Aβ42, while one control (10%) had

abnormal values. In contrast, AD patients both

mild and severe, 14/15(93.33%) had high CSF-T-

tau and low CSF- Aβ42, while 1/15(6.66%) had

normal levels of both markers. As regards

probable VaD 9/15(60%) had high CSF-T-tau and

low CSF-Aβ42, while 6/15(40%) had normal

levels of both markers (Table 4). Thus, the

sensitivity for high CSF-T-tau and/or low CSF-

Aβ42, for the prediction of AD was (93.33%),

while the specificity was (90%) when compared

with the control and 40% when compared with

VaD.

Table 1. Clinical characteristics of the studied groups.

Variables Control

(n=10)

Alzheimer’s disease (n=15) probable

vascular

dementia

(n=15)

F p Mild AD

(n=6)

Severe AD

(n=9)

Age(years) 67±4 65±7 71±4 66 ±8 1.45 0.222

Sex (♂/♀) 5/5 2/4 4/5 6/9

Duration of

dementia (months) - 38 ±27 40±28 38 ±21 0.48 P=0.621

MMSE 29.3±5 22.6 ±4.5 10±1.8 15 ±5.8 30.63 <0.001*

All groups are significantly differ

Table 2. CSF levels of T-tau, Aβ42, tTG activity among the studied groups.

Variables Control

(n=10)

Alzheimer’s disease (n=15) probable

vascular

dementia

(n=15)

F p Mild AD

(n=6)

Severe AD

(n=9)

T-tau (pg/ml) 225±88 300±90 700±270 280±130 17.29 <0.001*

All groups are significantly differ except mild vs. control, VaD vs. control and mild

vs. VaD

A β42(pg/ml) 875±262 400±100 255±87 550±206 17.08 <0.001*

All groups are significantly differ except mild vs. severe and mild vs. VaD

tTG activity (anilide

mol/min/mg protein)

0.41±0.03 0.75±0.09 0.89±0.07 0.51±0.09 81.87 <0.001*

All groups are significantly differ

Azza Ghali et al.

325

Table 3. Correlation between T-tau, Aβ42, tTG activity and other variables in Alzheimer's disease groups

(n=15).

Variables T-T-tau A β42 tTG activity

Age (years) 0.20 -0.18 0.12

Duration of dementia (month) 0.23 0.14 0.30

MMSE 0.28 0.22 0.07

T-T-tau (pg/ml) - -0.39* 0.33

A β42(pg/ml) -0.39* - -0.32

tTG activity (anilide mol/min/mg protein) 0.33 -0.32 -

Table 4. Sensitivity and specificity of the combined CSF T-tau and Aβ42 in Alzheimer’s disease.

Variables Cut-off Value Sensitivity

%

Specificity

%

Accuracy PPV

Probable Alzheimer’s

disease (n=15)

T-tau=306 (pg/ml)

Aβ42=500(pg/ml)

93.33% 90% (AD vs. C)

40% (AD vs. VaD)

92% 93.33%

Aβ42 = amyloid beta, AD= Alzheimer’s disease, VaD= vascular dementia, C = healthy control, PPV= positive

predictive value

DISCUSSION

The antemortem diagnosis of AD requires

time-consuming and costly procedures. Also, the

accuracy of the clinical diagnosis at the general

hospitals is probably even lower, especially in the

early stages of the disease when the symptoms are

indistinct. Therefore, biochemical tests that can

direct the physician rapidly to the correct

diagnosis should be able to detect a fundamental

feature of neuropathology. Furthermore, its

sensitivity for detection of AD as well as its

specificity for discrimination of AD from other

dementia disorders should exceed 80%. A marker

for AD should also be reliable, reproducible,

noninvasive, simple to perform in clinical routine

and inexpensive2. Measurement of single

biochemical markers in cerebrospinal fluid (CSF)

shows robust alterations that highly correlate with

the clinical diagnosis of AD but generally lack

sufficient diagnostic accuracy31

. So, in the present

study combined CSF measurements of T-tau (as a

marker for neuronal degeneration), Aβ42 (as a

marker for amyloid beta metabolism, and possibly

for the formation of senile plaques) and tTG (as a

marker for apoptosis) in 30 patients who under-

went diagnostic workup for dementia and in 10

healthy control subjects was done.

In the current study, there was a significant

increase in CSF activity of tTG in dementia groups

as compared with the control, with a significant

change on comparing probable AD with probable

VaD. This findings came in accordance with the

results Lesort et al., 11

who found that tTG level and

activity are elevated in both Alzheimer's and

Huntington's disease in post mortem. Jhonson and

coworkers 8

found that the levels of tTG, as

determined by quantitative immunoblotting, were

elevated approximately 3-folds in Alzheimer

disease prefrontal cortex, compared to control and

there were not significant differences in tTG levels

in the cerebellum between control and Alzheimer

disease cases. This elevated level of tTG may be

related to neurofibrillary pathology which is usually

abundant in the prefrontal cortex and not in the

cerebellum which is usually spared in Alzheimer

Egypt J. Neurol. Psychiat. Neurosurg. Vol. 43 (2) - July 2006

326

disease. They suggested that tTG could be a

contributing factor in neurofibrillary tangle

formation because tTG is calcium-activated, and

tau is an excellent substrate of this enzyme in vitro.

The increased intracellular calcium levels in AD

activate tTG which converts tau to neurofibrillary

tangles32,33

. Furthermore, Bonelli et al.,16

proposed

that the concentration of CSF tTG in relation CSF

tau and AB42 is an indicator for acute cell death in

vivo. The CSF tTG levels appears to be elevated in

AD patients due to the increased apoptotic process;

the protein seems to be released into the

extracellular space after cell disruption. Therefore,

inhibition of transglutaminase-induced cross-linking

may provide a novel strategy for treatment of AD.

The In the current study, the missing association

between CSF activity of tTG and MMSE shows

that tTG may not serve as an indicator for mental

decline.

It has been suggested that CSF T-tau

concentrations are a good reflection of the actual

degree of neurofibrillary degeneration in the brain,

and implying that CSF T-tau concentrations may

increase with increasing neurofibrillary tangles

(NFTs) load and thus with disease progression34

.

The data presented here in confirmed previous

findings of Andreasen et al., 35

; Galasko et al.36

, and

Rösler et al.37

, of a pronounced increase in CSF-T-

tau in Alzheimer’s disease and suggested that the

CSF T-tau levels reflect the degree of neuronal

(especially axonal) degeneration and damage 38

, as

evidenced by a transient increase in CSF T-tau after

acute stroke39

. This increase probably reflects

leakage of T-tau from damaged neurons to the

CSF29

. An increased level of CSF T-tau is indeed

not a specific marker for AD, but appears also in

other neurological diseases, such acute cerebral

stroke, Creutzfeldt-Jakob disease, frontotemporal

dementia, dementia with Lewy’s bodies or

Parkinson’s disease. However, CSF T-tau is

generally lower in these pathologies than in AD20

.

Also, Mulder et al.6, and Parnetti et al.

40, found

increase of CSF T-tau in AD in the earlier stages of

dementia, which makes this measurement useful for

early diagnosis of AD. In the present study there

was no correlation between CSF-T-tau and duration

of dementia which came in accordance with Isoe et

al.41

. These findings suggested that high CSF-T-tau

concentrations are present during the whole course

of the disease. It is possible that the same high CSF-

T-tau concentrations are also found before the onset

of clinical dementia. If so, CSF-T-tau may be useful

for selection of patients with early memory dis-

turbances for clinical drug trials29

.

Concomitantly it has been found that CSF-T-

tau has a high sensitivity for the diagnosis of AD29

.

In total, 41/43 (95%) patients with AD had a CSF-

T-tau concentration above the cut off level of 306

pg/ml in healthy controls. However, the specificity

was lower, as almost all (86%) patients with VaD

also had high CSF-T-tau concentrations. In the

current study, high CSF-T-tau concentrations were

also found in patients with VaD, resulting in a low

diagnostic specificity of CSF-T-tau for AD. The

high CSF-T-tau concentrations found in VaD may

in part be explained by the fact that, these patients

may, in addition to cerebro-vascular pathology,

have concomitant AD pathology, which is impos-

sible to be excluded clinically. Indeed, several

neuropathological studies found that a high

proportion (40–80%) of clinically diagnosed

patients with VaD have notable concomitant AD

pathology42,43

.

The central protein in SPs is Aβ42. It is

produced and secreted from human cells as a result

of normal cellular processing of the larger tran-

membrane protein APP44

. It is possible that Aβ42

accumulation triggers the hyperphosphorylation of

T-tau protein which precedes the assembly of these

molecules into filaments6. Previous studies came in

accordance with the results of the current study that

demonstrated a moderate to marked decrease in

CSF Aβ42 in AD with no significant correlation

with age, MMSE or duration of AD symptoms26,45

.

The possible cause of low CSF- Aβ42 levels, may

be, axonal degeneration and entrapment in narrow

interstitial and subarachnoid drainage pathways46,47

.

The lack of a clear relationship among CSF Aβ42

level, severity of dementia, and duration of

disease in this study is consistent with studies

showing that plaque accumulation and brain

amyloid burden do not correspond to duration and

Azza Ghali et al.

327

severity of AD48

. In contrast, Csernansky et al.49

,

found that increased severity of dementia was

correlated with increased CSF T-tau

concentrations and decreased Aβ42 concentrations.

The mean sensitivity of CSF Aβ42 for

discrimination between AD and normal aging is

approximately 86%, while the specificity is

approximately 91%. On the other-hand, the

specificity for discrimination of AD from other

disorders is moderate. Low levels of Aβ42 in CSF

have been found in other neurodegenerative

disorders50,47

. Therefore, in the present study

concomitant measurements of CSF T-tau and Aβ42

was performed which have been suggested to

increase the diagnostic precision of AD. These

biochemical markers seem to have clinical value

in the very early phase of probable AD and

patients with low CSF Aβ and high CSF T-tau

have a strong likelihood of having AD.

Conversely, patients who exhibit low T-tau and

elevated Aβ42 are free of AD51

. Andreasen and

his colleges35

found that, the sensitivity for the

diagnosis of mild cognitive impairment by using

the combination of T-tau and Aβ42 was 75%.

These results confirm the findings of aberrant CSF

T-tau and Aβ42 concentrations early in the course

of the disease, independent of disease progression.

Also, it has been deduced that the CSF markers

(T-tau and Aβ42) should be combined with the

clinical information and brain-imaging

techniques44

. Finally, the current study concluded

that, the sensitivity and specificity increased if

CSF-T-tau and CSF- Aβ42 were used together.

The level of CSF-T-tau has been suggested to

reflect the neuronal and axonal degeneration in

AD and/or the formation of neurofibrillary

tangles, while the level of CSF- Aβ42 has been

suggested to reflect the deposition of β-amyloid in

senile plaques, with lower levels excreted to the

CSF. Thus, both these analyses probably reflect

central pathogenic processes in the AD brain,

which, however, may vary in intensity between

patients. Therefore, it seems logical that the

combined use of these markers will increase the

sensitivity, specificity and adds to the accuracy of

an AD diagnosis19

.

Conclusion: the present results suggested

that tTG may be a powerful biochemical marker

of the degenerating process in vivo. It may serve

as completion of CSF analysis in the diagnosis of

dementing disorders and may be a simple way of

assessing the efficacy of possible new

antiapoptotic drugs. In addition, the diagnostic

usefulness of the CSF content of both T-tau and

Aβ42 is superior to either measure alone with high

sensitivity and specificity for prediction of AD,

and can be recommended as an aid to evaluating

individuals suspected of having dementia.

REEFRENCES

1. Ankarcrona M, Winblad B. (2005): Biomarkers

for apoptosis in Alzheimer's disease. Int J Geriatr

Psychiatry 20(2):101-5.

2. Sjogren M, Andreasen N, Blennow K. (2003):

Advances in the detection of Alzheimer's disease-

use of cerebrospinal fluid biomarkers. Clin Chim

Acta. 332(1-2):1-10.

3. Cummings JL. (2004). Alzheimer's disease. N

Engl J Med;1;351(1):56-67.

4. Ho GJ, Gregory EJ, Smirnova IV, Zoubine MN,

Festoff BW. (1994): Cross-linking of beta-

amyloid protein precursor catalyzed by tissue

transglutaminase. FEBS Lett; 349(1):151-4.

5. Verbeek MM, de Jong D, Kremer HPH. (2003):

Brain-specific proteins in cerebrospinal fluid for

the diagnosis of neurodegenerative diseases. Ann.

Clin. Biochem; 40:25-40.

6. Mulder C, Scheltens P, Visser JJ, Van Kamp GJ

and Schutgens RBH. (2000): Genetic and

biochemical markers for Alzheimer's disease:

recent developments. Ann. Clin. Biochem., 37:

593-607.

7. Guillozet-Bongaarts AL, Garcia-Sierra F,

Reynolds MR, Horowitz PM, Fu Y, Wang T,

Cahill ME, Bigio EH, Berry RW, Binder LI.

(2005): T-tau truncation during neurofibrillary

tangle evolution in Alzheimer's disease.

Neurobiol Aging. 26(7): 1015-22.

8. Johnson GV, Cox TM, Lockhart JP, Zinnerman

MD, Miller ML, Powers RE. (1997):

Transglutaminase activity is increased in

Alzheimer's disease brain. Brain Res.; 751(2):

323-9.

Egypt J. Neurol. Psychiat. Neurosurg. Vol. 43 (2) - July 2006

328

9. Tucholski J, Kuret J, Johnson GV. (1999): T-tau

is modified by tissue transglutaminase in situ:

possible functional and metabolic effects of

polyamination. J Neurochem.; 73(5): 1871-80.

10. Lesort M, Chun W, Tucholski J, Johnson GV.

(2002): Does tissue transglutaminase play a role

in Huntington's disease? Neurochem Int; 40(1):

37-52.

11. Lesort M, Tucholski J, Miller ML, Johnson GV.

(2000): Tissue transglutaminase: a possible role

in neurodegenerative diseases. Prog Neurobiol.;

61(5): 439-63.

12. Citron BA, Suo Z, SantaCruz K, Davies PJ, Qin

F, Festoff BW.(2002): Protein crosslinking, tissue

transglutaminase, alternative splicing and

neurodegeneration. Neurochem Int.; 40(1): 69-

78.

13. Cooper AJ, Jeitner TM, Gentile V, Blass JP.

(2002): Cross linking of polyglutamine domains

catalyzed by tissue transglutaminase is greatly

favored with pathological-length repeats: does

transglutaminase activity play a role in

(CAG)(n)/Q(n)-expansion diseases?. Neurochem

Int.; 40(1): 53-67.

14. Autuori F, Farrace MG, Oliverio S, Piredda L.

(1998): Piacentini M"Tissue" transglutaminase

and apoptosis. Adv Biochem Eng Biotechnol; 62:

129-36.

15. Chen JS, Mehta K (1999):Tissue

transglutaminase: an enzyme with a split

personality Int J Biochem Cell Biol;31(8):817-3.

16. Bonelli RM, Aschoff A, Niederwieser G,

Heuberger C, Jirikowski G. ( 2002 ):

Cerebrospinal fluid tissue transglutaminase as a

biochemical marker for Alzheimer's disease.

Neurobiol Dis.; 11(1):106-10.

17. Kim SY, Grant P, Lee JH, Pant HC, Steinert PM.

(1999): Differential expression of multiple

transglutaminases in human brain. Increased

expression and cross-linking by

transglutaminases 1 and 2 in Alzheimer's disease.

J Biol Chem; 22;274(43): 30715-21.

18. Kwak SJ, Kim SY, Kim YS, Song KY, Kim IG,

Park SC. (1998): Isolation and characterization of

brain-specific transglutaminases from rat. Exp

Mol Med; 31;30(4): 177-85.

19. Maccioni RB, Lavados M, Maccioni CB,

Mendoza-Naranjo A. (2004): Biological markers

of Alzheimer's disease and mild cognitive

impairment. Curr Alzheimer Res; 1(4):307-14.

20. Leszek J, Malyszczak K, Janicka B, Kiejna A,

Wiak A. (2003): Total T-tau in cerebrospinal

fluid differentiates Alzheimer's disease from

vascular dementia. Med Sci Monit.; 9(11):

CR484-8.

21. American Psychiatric Association (AMP) (1994):

Diagnostic and Statistical Manual of Mental

Disorders, 4 th edition DSM VI, Washinton D.C.

22. McKhann G, Drachman D, Folstein M, Katzman

R, Price D. and Stadlan EM. (1984): Clinical

diagnosis of Alzheimer’s disease: Report of the

NINCDS-ADRDA Work Group under the

auspices of Department of Health and Human

Services Task Force on Alzheimer’s Disease.

Neurology 34, 939–944.

23. Hachinski VC, Hiff LD, Zilhka E, Du Boulay

GH, McAllister VL, Marshall J., et al. (1975):

Cerebral blood flow in dementia. Arch. Neurol;

32: 632–637.

24. Roman GC, Tatemichi TK, Erkinjuntti T,

Cummings JL, Masdeu JC. and Garcia JH.

(1993): Vascular dementia: Diagnostic criteria for

research studies. Report of the NINDSAIREN

International Workshop. Neurology 43, 250–260.

25. Vandermeeren M, Mercken M, Vanmechelen E.

(1993): Detection of proteins in normal and

Alzheimer’s disease cerebrospinal fluid with a

sensitive sandwich enzyme-linked

immunosorbent assay. J Neurochem; 61: 1828–

34.

26. Mehta PD, Pirttila T, Mehta SP, Sersen EA,

Aisen PS, Wisniewski HM. (2000): Plasma and

cerebrospinal fluid levels of amyloid beta

proteins1–40 and 1–42 in Alzheimer disease.

Arch Neurol; 57:100–5.

27. De Macedo P, Marrano C. and Keillor J.

(2000) :A direct continuous spectrophotometric

assay for transglutaminase activity. Anal.

Biochem; 285, 16-20.

28. Lowry O, Rosebrough N, Farr A. and Randall R.

(1951): Protein measurement with the folin

phenol reagent. J. Biol. Chem., 193: 265-275.

29. Andreasen N, Minthon L, Vanmechelen E.

(1999): Cerebrospinal fluid T-tau and Aβ42 as

predictors of development of Alzheimer’s disease

in patients with mild cognitive impairment.

Neurosci Lett; 273: 5-8.

30. Andreasen N, Vanmechelen E, Van de Voorde E,

Davidsson P, Hesse C, Tarvonen S, RaÈ ihaÈ I.,

Sourander L, Winblad B. and Blennow K.

(1998): Cerebrospinal fluid T-tau protein as a

biochemical marker for Alzheimer's disease: a

community based follow up study. J. Neurol.

Neurosurg. Psychiatry 64 298-305.

Azza Ghali et al.

329

31. Maddalena A, Papassotiropoulos A, Muller-

Tillmanns B, Jung HH, Hegi T, Nitsch RM, Hock

C. (2003):Biochemical diagnosis of Alzheimer

disease by measuring the cerebrospinal fluid ratio

of phosphorylated T-tau protein to beta-amyloid

peptide42. Arch Neurol. ; 60(9):1202-6.

32. Norlund MA, Lee JM, Zainelli GM, Muma NA.

(1999): Elevated transglutaminase-induced bonds

in PHF T-tau in Alzheimer's disease. Brain Res

;851(1-2):154-63.

33. Case A, Stein RL. (2003): Kinetic analysis of the

action of tissue transglutaminase on peptide and

protein substrates. Biochemistry.42(31): 9466-81.

34. Tapiola T, Overmyer M, Lehtovirta M, Ramberg

J. (1997): The level of cerebrospinal fluid T-tau

correlates with neurofibrillary tangles in

Alzheimer's disease. Neuroreport; 8:3961-3.

35. Andreasen N, Minthon L, Davidsson P,

Vanmechelen E. (2001): Evaluation 0f CSF T-tau

and CSF A beta 42 as diagnostic markers for

Alzheimer's disease in clinical practice. Arch.

Neurol; 58:373-9

36. Galasko D, Clark C, Chang L. (1997):

Assessment of CSF levels of T-tau protein in

mildly demented patients with Alzheimer’s

disease. Neurology 48:632–5.

37. Rösler N, Wichart I, Jellinger KA. (1996): Total T-

tau protein immunoreactivity in lumbar

cerebrospinal fluid of patients with Alzheimer’s

disease. J Neurol Neurosurg Psychiatry 60: 237–8.

38. Blennow K, Wallin A, Agren H, Spenger C,

Siegfried J, Van-mechelen E. (1995): T-tau

protein in cerebrospinal fluid: a biochemical

marker for axonal degeneration in Alzheimer

disease? Mol Chem Neuropathol; 26:231–45.

39. Hesse C, Rosengren L, Vanmechelen E. (2000):

Cerebrospinal fluid markers for Alzheimer’s

disease evaluated after acute ischemic stroke. J

Alzheimer’sDis; 2 :199–206.

40. Parnetti L, Lanari A, Saggese E, Spaccatini C,

Gallai V. (2003): Cerebrospinal fluid biochemical

markers in early detection and in differential

diagnosis of dementia disorders in routine clinical

practice. Neurol Sci.; 24(3):199-200.

41. Isoe K, Urakami K, Shimomura T, Wakutani Y,

Ji Y, Adachi Y, Takahashi K. (1996): T-tau

proteins in cerebrospinal fluid from patients with

Alzhei-mer’s disease: a longitudinal study

[Letter]. Dementia 7:175– 6.

42. Jellinger KA. (1996): Diagnostic accuracy of

Alzheimer’s disease: a clinicopathological study.

Acta Neuropathol; 91:219–20.

43. Kosunen O, Soininen H, Paljärvi L. (1996):

Diagnostic accuracy of Alzheimer’s disease: a

neuropathological study. Acta Neuropathol;

91:185–93

44. Andreasen N, Sjogren M, Blennow K. (2003):

CSF markers for Alzheimer's disease: total T-tau,

phospho-T-tau and Abeta42. World J Biol

Psychiatry. 4(4):147-55.

45. Tamaoka A, Sawamura N, Fukushima T. (1997):

Amyloid beta protein 42(43)in cerebrospinal fluid

of patients with Alzheim-er’s disease.J Neurol

Sci;148:41–5.

46. Ichihara N, Wu J, Chui DH, Yamazaki K,

Wakabayashi T, Kikuchi T. (1995): Axonal

degeneration promotes abnormal accumulation of

amyloid beta-protein in ascending gracile tract of

gracile axonal dystrophy(GAD)mouse. Brain

Res;695:173–8

47. Sjogren M, Minthon L, Davidsson P. (2000):

CSF levels of T-tau, beta-amyloid(1–42)andGAP-

43 in fronto temporal dementia, other types of

dementia and normal aging. J Neural Transm;

107:563–79.

48. Southwick PC, Susan KY, Charles LE. (1996):

Assessment of Amyloid β protein in

cerebrospinal fluid as anaid in the diagnosis of

Alzheimer’s disease. J. Neurochem;66:259-65

49. Csernansky JG, Miller JP, McKeel D, Morris JC.

( 2002): Relationships among cerebrospinal fluid

biomarkers in dementia of the Alzheimer type.

Alzheimer Dis Assoc Disord. ; 16(3):144-9.

50. Kanemaru K, Kameda N, Yamanouchi H. (2000):

Decreased CSF amyloid beta 42 and normal T-tau

levels in dementia with Lewy bodies. Neurology

54:1875–6.

51. Kanai M, Matsubara E, Isoe K, Arai H. (1998):

Longitudinal study of cerebrospinal fluid levels

of T-tau , A beta 1-40, and A beta 1-42 in

Alzheimer's disease: a study in Japan. Ann.

Neurol; 44:17-26.

ــص العربـــىخالمل

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