eISSN: 1509-572x
ISSN: 1641-4640
Folia Neuropathologica
Current issue Archive Manuscripts accepted About the journal Journal's reviewers Abstracting and indexing Subscription Contact Instructions for authors
SCImago Journal & Country Rank
vol. 56
Original paper

Vitamin E can compensate the density of M1 receptors in the hippocampus of scopolamine-treated rats

Ali Sayyahi, Mehrdad Jahanshahi, Hossein Amini, Hamid Sepehri

Folia Neuropathol 2018; 56 (3): 215-228
Online publish date: 2018/09/28
Article file
- Vitamin E.pdf  [0.67 MB]
Get citation
JabRef, Mendeley
Papers, Reference Manager, RefWorks, Zotero


One kind of G-protein coupled receptors is muscarinic acetylcholine receptors [16,68,95]. So far, five muscarinic acetylcholine receptor subtypes (M1-M5) have been known [13,14,27] and among them, the M1 subtype makes up more than a half of the total and mainly exists in all major zones of the forebrain, such as the cortex, the hippocampal formation, corpus striatum of basal nuclei, and thalamus [30,36,65]. Indeed, M1 muscarinic receptors are highly concentrated in the brain areas related to Alzheimer’s disease (AD) but less in the periphery [59,60]. Cognitive deficits and damage in long-term potentiation were shown in M1 muscarinic receptor-knockout mice, indicating that this receptor is physiologically related to multiple roles such as neuronal excitability, synaptic plasticity, and differentiation of neurons during early development, and memory [3,41,65,83,84,94,96]. Because M1 muscarinic receptor plays a critical role in memory and is closely linked with AD, it has long been guessed as a target for therapy [28]. Previous studies reported the precognitive effects of M1 muscarinic receptor activators and have used models in which the cholinergic function is damaged with scopolamine, a non-selective muscarinic receptor antagonist [78]. Scopolamine is well known for interfering with the methods of learning acquisition, memory performance and short-term memory in animals and humans [32,47,63]. The post-training scopolamine dose-dependently decreased the step-through latency in the inhibitory avoidance task; it shows scopolamine-induced amnesia [42]. Also, scopolamine reduced dose-dependently the number of M1 muscarinic receptor-immunoreactive (ir) neurons in the male rats’ hippocampus [44]. Moreover, scopolamine directly caused damage to the hippocampal circuits that might predominantly be responsible for cognitive and memory deficits [18]. The chronic systemic treatment with scopolamine significantly disrupted cell proliferation, differentiation and maturation, especially, impaired the dendrite maturation and complexity of neuronal progenitor cells in the mouse hippocampal dentate gyrus (DG) [100]. A common way for a large number of degenerative routes in AD is the neuronal loss [87,93] and may be prompted by some factors, such as perturbed calcium regulation, inflammatory routes or oxidative stress, ischemia, amyloid- plaques and glutamate [8,19,72]. Additionally, most researches have concentrated broadly on amyloid- deposits and neurofibrillary pathology in AD, while neuronal loss has been more difficult to assess [86]. In the AD hippocampus, the neuronal loss can describe the memory disorders which are clinical signs, even in the preclinical stages [53]. The loss of neurons is commonly prominent in the hippocampus, mainly the CA1 region, and is further noticed throughout the cerebral cortex, increasing with disease progression [15]. Also, in both AD and normal aging, the distribution of the neuronal loss in the hippocampus is not very well understood [97]. This selective loss of neurons could locally be related to understanding the complicated mechanism of AD [73]. Also, a neuronal loss in the hippocampus in microvascular dementia patients was described in 2002 by Kril et al. [55]. This could have essential suggestions in the design of therapeutic and investigative strategies in AD [73]. Drugs currently used for AD only controlled the symptoms and slow the progression of the cognitive decline. There is no effective treatment to delay or stop the progressive brain damage [22].
Numerous studies have documented increased oxidative stress in the plasma and cerebro-spinal fluid of AD patients, which can be observed as an increase in lipid peroxidation [9,80]. Therefore, antioxidants, such as vitamin E, have frequently been discussed as a potential therapeutic option in AD [5,58]. Health benefits of vitamin E include antioxidant, neuroprotective, and anti-inflammatory properties [70]. Vitamin E can reduce or prevent memory deficiencies that accompany several disorders for example mental stress [67], ischemic injury of cerebrum [1], AD [50,79], stroke [88] and aging [48]. The effect of vitamin E supplements on memory damage has been studied in aged rats, it caused marked retention of their memory function [90]. Moreover, when vitamin E was given to moderately severe AD patients, those patients showed delayed beginning of severe dementia [79]. It has been shown that long-term, high-dose vitamin E supplementation in the elderly significantly develops the cognitive function [34]. Although trials examining the efficacy of vitamin E supplementation in the AD treatment have yielded inconclusive results [25,61,76,79], a combination of -tocopherol and inhibitors of angiotensin-converting-enzyme have been newly confirmed as effective in attenuating the cognitive decay in AD patients [21]. Taken together, these findings and others [17,54,69,82] determine a crucial role for vitamin E in preserving emotional responses, learning and memory. Importantly, vitamin E has been described to have more interaction with the cholinergic system in processes of memory retention [23]. Since vitamin E decreased scopolamine-induced damage on memory retention; it may act through activation of the cholinergic system on memory retention [23]. However, to the best of our knowledge, there have been no reports on the density of M1 muscarinic neurons that contain receptors in the hippocampus after administration of vitamin E.
Therefore, the present study examined the effect of chronic administration of vitamin E on scopolamine-induced AD-like impairment memory and the changes of M1 muscarinic receptor-ir neurons number in the male rat hippocampus.

Material and methods


Forty-two male adult Wistar rats (8 weeks old; 200 ±20 g) were provided by the Pasteur Institute (Tehran, Iran). The animals were maintained in individual cages with a 12 : 12 hour light and dark cycle (light beginning at 7:00 a.m.) and also they had free access to water and food. The temperature of the animal house was 22 ±3ºC. All experiments were performed during the light phase between 8:00 a.m. and 14:00 p.m. The Ethics Committee in Golestan University of Medical Sciences approved all procedures described in the method. We tried to use the minimum number of rats and we tried to minimize the suffering of animals.

Inhibitory avoidance apparatus

The inhibitory avoidance task, step-through, consisted of the same size (20 × 20 × 30 cm3) light and dark boxes. Between two boxes, a guillotine door (7.9 cm2) could be lifted manually. The floor of the dark box was made by stainless steel bars with 1 cm intervals. An isolated stimulator produced sporadic electric shocks (50 Hz, 3 s, and 1.5 mA intensity) to the grid floor of the dark chamber.

Behavioral procedures

Our previous studies [62,81] explained passive avoidance memory as follows: for 1 h before the start of the tests, rats were allowed to habituate in the testing room. Then, one rat was placed in the light box; after 5 s, the guillotine door was opened. The animal can enter the dark chamber. The latency was recorded to entrance the dark compartment. After waiting more than 120 s to enter the dark box, this rat was excluded from the experiments.
When all four-paws of the animal entered the next compartment, the guillotine door was closed. This trial was repeated after 30 min. In the acquisition trial, when the animal entered the dark (shock) box, the door was closed. Immediately a foot shock (50 Hz, 1.5 mA and 3 s) was sent to the grid floor of the dark chamber. After this shock, the rat was removed from the Shuttle Box. Two minutes later, the test was repeated and if the rat did not enter the dark box during 120 s, positive acquisition of inhibitory avoidance response was recorded. The rat was backed to the cage, if it learned inhibitory avoidance response successfully.
Each animal on the test day was gently placed in the light box for the retention trial and the latency time to enter the dark box was recorded and termed as step through latency. The retention trial was set a limit of 300s as cut-off time.

Experimental design

We distributed the rats randomly to the following groups (n = 7):
Control group: had no any drugs and behavioral tests;
Scopolamine-saline group: receiving scopolamine (Tocris, UK) with a single dose of 3 mg/kg (i.p.) for a day [45], and then an injection of 0.9% sterile saline (1 ml/kg, i.p.) for fourteen days, and with a behavioral test;
Scopolamine-sesame oil group: receiving a single dose of scopolamine 3 mg/kg for a day and then receiving sesame oil (1 ml/kg, i.p.) for fourteen days, and with the behavioral test;
Three scopolamine-vitamin E treated groups: receiving a single dose of scopolamine 3 mg/kg for a day and then an injection of vitamin E (Darou Pakhsh Pharmaceutical Mfg Co., Iran) with different doses (25, 50, and 100 mg/kg/day, i.p.) [7,23,38] for fourteen days, and with the behavioral test.
Scopolamine, a muscarinic receptor antagonist, was dissolved in 0.9% sterile saline and vitamin E was dissolved in sesame oil. Twenty four hours after the scopolamine injection and the last injection of drugs, the rats were tested for the retention trial in inhibitory avoidance apparatus.

Perfusion and sectioning

Twenty-four hours after the end of the behavioral test, the rats were transcardially perfused with normal saline and then with 4% paraformaldehyde solution (Scharlau, Spain). The brains were removed and fixed in 4% paraformaldehyde for a week. After dehydration and clarification with xylene, the paraffin blocks of brains were prepared. Coronal serial sections (6-µm thick) of the brain with an interval of 20 µm were processed for immunohistochemical and cresyl violet staining [66].

Immunohistochemical staining

The process of staining with the antibody against M1 muscarinic receptor was as follows [44]:
1. Incubation of the brain slices at 37°C for 30 minutes.
2. Deparaffinization and hydration of slices embedded in xylene and a graded series of ethanol.
3. Washing with distilled water.
4. After incubation at 60°C for 5 minutes, the sections were covered with an epitope retrieval solution (IHC World, USA) at 90°C for 15 minutes.
5. For cooling, they were endorsed for 20 minutes at room temperature.
6. Washing with washing buffer (PBS/Tween 20 in 0.1% Triton X-100).
7. For 10 minutes at room temperature, the peroxidase blocking solution (IHC World, USA) was used.
8. For 30 minutes at room temperature, the slices were incubated with the avidin/biotin blocking solution (IHC World, USA) and rinsed with PBS.
9. For 60 minutes at 37°C, sections were covered with the Anti-Muscarinic Acetylcholine Receptor 1 Rabbit polyclonal antibody (1 : 200, Abcam Inc., USA) and then the washing buffer.
10. After this step, slices must be incubated for 60 minutes with immunoglobulin G (IgG) (Abcam Inc., USA) at 37°C and washed with the washing buffer.
11. Incubation with Streptavidin HRP protein (1 : 5000, Abcam Inc., USA) at room temperature for 30 minutes and the washing buffer.
12. By using DAB (Dako, Denmark), the M1 muscarinic receptors were visualized.
13. Finally, the brain slices were cover-slipped with entellan (Merck, Germany).

Cresyl violet staining

The brain slices were deparaffinized in xylene and hydrated with ethanol and washed with distilled water. Then, the sections were stained for 5 min in 0.02% cresyl violet (Sigma, USA) solution and washed quickly in distilled water. Finally, the slices were cover-slipped with entellan [81].

Image processing and cell counting

Using a BX51light microscope (Olympus, Japan) and DP 72 digital camera (Olympus, Japan), images were taken. 40× magnification for hippocampal CA1 and CA3 areas (30 000 µm2) and 100× magnifications for DG area (4800 µm2) in all sections were selected randomly. To count the number of M1 muscarinic receptor-ir neurons in the hippocampus, OLYSIA Autobioreport software (Olympus, Japan) was used, the M1 muscarinic receptor-ir neurons were counted manually [43,46,49] and counting was performed blind to treatment.

Statistical analysis

All of our data were expressed as mean ± SD. SPSS v.16 (Armonk, NY, USA) was used for statistical analysis. For normal distribution of data, the Shapiro-Wilk test was approved for the statistical evaluation. We analyzed the data with the one-way analysis of variance (ANOVA) followed by post-hoc LSD (least significance difference) test for over-all various comparisons between groups and p < 0.05 was considered to be statistically significant.


During the memory retention test, the latency to enter the dark box was reduced after scopolamine treatment compared to the training day, indicating memory impairment (Fig. 1). Vitamin E administration (25, 50, and 100 mg/kg/day) increased significantly the step-through time of latency when compared to the scopolamine-saline group (p < 0.01, p < 0.001 and p < 0.001, respectively, Fig. 1), showing improved memory retention. There is a significant difference in step-through latency time between the 50 mg/kg/day dose of vitamin E compared to the 25 mg/kg/day dose of vitamin E (p < 0.001, Fig. 1). These results reveal that vitamin E, only at an intermediate dose (50 mg/kg/day), inhibited the harmful effects of scopolamine. In Figure 2, coronal sections of the hippocampus for CA1 area stained by immunohistochemistry anti-M1 muscarinic receptor was shown.
Furthermore, Figure 3 shows the number of neurons contained in the M1 muscarinic receptor-ir in the rat hippocampus. An injection of scopolamine caused the hippocampal M1 muscarinic receptor-ir neuron loss in the CA1, CA3 and dentate gyrus. Comparison of the mean number of M1 muscarinic receptor-ir neurons in control and scopolamine-saline groups of rats revealed that scopolamine significantly reduced the number of M1 muscarinic receptors in different areas of the hippocampus (p < 0.001, Figs. 3A and B). In the scopolamine-saline group, the mean number of neurons with the M1 muscarinic receptors in the CA1 area was 25.52 ±9.05, and in the CA3 area it was 20.30 ±5.54, respectively.
We found that vitamin E significantly raised the amount of M1 muscarinic receptor-ir neurons in all areas of the hippocampus compared to the scopolamine-saline group (Figs. 3A-C). According to our findings, a 50 mg/kg/day dose of vitamin E appears to attenuate the scopolamine-induced M1 muscarinic receptor-ir neuron loss in all areas of the hippocampus (Figs. 3A-C). The higher mean number of M1 muscarinic receptor-ir neurons for the vitamin E-treated group with a dose of 50 mg/kg/day was 38.12 ±14.54 in the CA1 area of the hippocampus (Fig. 3C).
Figure 4 shows a representative cresyl violetstained coronal section of the hippocampal CA1 area. In the scopolamine-treated groups, CA1 and CA3 pyramidal neuron numbers (25.62 ±7.27, 24.60 ±8.36 respectively) were significantly decreased as compared to the control group (40.20 ±13.52, 31.82 ±7.79, respectively) (Figs. 5A, B, p < 0.001). Indeed, an intraperitoneal injection of scopolamine caused the hippocampal cell loss. Vitamin E treatment significantly increased the number of pyramidal neurons in the CA1 and CA3 areas. Comparison of the mean number of neurons in vitamin E-treated groups revealed that vitamin E (50 mg/kg/day dose) has a significant neuroprotective effect on the scopolamine-induced neuron loss (Figs. 5A, B). The mean number of neurons in CA1 and CA3 for the vitamin E-treated group (with a dose of 50 mg/kg/day) was 38.80 ±8.14 and 31.20 ±8.39, respectively.
The mean number of DG granular neurons (19.42 ±4.86) after scopolamine treatment was significantly decreased (Fig. 5C, p < 0.001) as compared to the control group (36.15 ±12.01). The comparison between scopolamine-saline and vitamin E-treated groups revealed that vitamin E increases significantly the scopolamine-induced neuron reduction (Fig. 5C, p < 0.001). The most effective dose of vitamin E was 50 mg/kg/day and it protects hippocampal DG granular neurons against scopolamine. The mean number of granular neurons for the vitamin E-treated group with a dose of 50 mg/kg/day was 34.15 ±9.42 neurons.


The present study suggested that vitamin E could increase M1 muscarinic receptor-ir neuron density in the hippocampus of scopolamine-treated rats. Also, vitamin E treatment could improve the scopolamine-induced neuronal loss and memory impairment. Vitamin E seems to have a significant neuroprotective effect on scopolamine.
In this study, we found that a single dose of scopolamine, as an antagonist of muscarinic receptors, could impair passive avoidance memory. Similarly, several lines of evidence have shown that scopolamine can cause a very potent impairment on tests of memory [20,37,40]. Moreover, an intrahippocampal [6] or intra-peritoneal [56,81] injection of scopolamine impairs the passive avoidance memory. Some previous studies indicate that both subtypes, M1 and M2, of muscarinic receptors were important for memory association of inhibitory avoidance [77].
In the present study, vitamin E treatment significantly improves the passive avoidance memory. Consistently with our findings, some studies demonstrated that vitamin E potentiated memory retention [23,38,51]. Also vitamin E has been reported to avoid the aging-induced memory deficits [29,90]. It has been reported that vitamin E with activation of the cholinergic system could help the memory maintenance [23].
According to our findings, our previous research confirms that a scopolamine injection causes cell loss in hippocampal neurons [81]. Also, another study has reported a significant loss of hippocampal neurons especially in both CA1 and CA3 areas in AD [73]. Besides, previous studies have shown that neuronal loss has occurred in many mouse models of AD [10,12,39,99] and AD patients [98].
Also, we found that vitamin E can increase hippocampal pyramidal and granular neuron numbers after the scopolamine injection. Vitamin E can cause delay or inhibit a clinical diagnosis of AD in elderly people with mild cognitive impairment [35]. Also, Nishida et al. indicated that chronic lipid peroxidation due to vitamin E depletion enhances the AD phenotype in a mouse model [71]. Moreover, memory weakening was slowed in moderately severe AD patients when they took vitamin E supplements [2]. Furthermore, it has been shown that long-term high dose vitamin E supplementation in the elderly patients significantly increases the cognitive function [34].
Consistently with earlier findings [44], our results revealed that treatment of Wistar rats with scopolamine led to decrease M1 muscarinic receptor-ir neuron numbers in the hippocampus. Similarly, after an injection of scopolamine to dogs, the older dogs showed a significant decrease in the density of the muscarinic receptor in some areas of cortex [4]. Similarly to our study, Araujo et al. found a decrease in muscarinic neurons. Furthermore, the M1 immunoreactivity was markedly decreased in AD brains [85] and also an age-related decrease in the M1 receptor has been reported [91]. Some other researches confirm a scopolamine injection, severe cell losses in hippocampal cholinergic neurons [44,57].
The present study showed that vitamin E treatment increases the hippocampal M1 muscarinic receptor-ir neuron numbers in scopolamine-treated rats. Recent studies have shown many useful health effects of vitamin E such as antioxidant and anti-inflammatory properties [52]. Many studies reported that vitamin E can act as an antioxidant in opposition to oxidative factors [74,75,89]. Some studies have revealed that vitamin E can decrease the levels of brain lipid peroxidation and protects it against neuronal damage [11,64,92]. Similarly, we have found that vitamin E compensates the reduction of M1 muscarinic receptor-ir neuron numbers in scopolamine-treated rats. Nevertheless, there are a few studies along the mechanisms to describe the effects of vitamin E. Moreover, vitamin E could have different roles distant from being an antioxidant in cellular mechanisms [24].
The role of vitamin E in protection against AD pathology has also described [31]. Experiments in vitro and in vivo confirmed a mechanism of vitamin E protection against the formation of the hyperphosphorylated tau. In this case, vitamin E was able to inhibit the activation of p 38 mitogen-activated protein kinases, whose activity is critical for the phosphorylation of neuronal tau molecules [31]. Therefore, further research is required to verify the evidence that vitamin E as a nutritional compound can endorse healthy brain ageing and helps to delay the AD-related functional decline [26].
Antioxidative effects of vitamin E, under certain conditions, may also be useful in the brain. However, beside these helpful roles, vitamin E potentially can increase amyloid-. -tocopherol which differs among vitamin E types, has the weakest amyloidogenic potency. So, further researches are suggested to explain the potential role of these various vitamin E species with respect to AD and to detect which form has antioxidative properties without having an amyloidogenic potential [33].
In conclusion, our results reveal that vitamin E can compensate the neuronal loss and it can increase the number of M1 muscarinic receptor-ir neurons in the hippocampus after exposure to scopolamine. Therefore, vitamin E may have a therapeutic significance for AD.


This article resulted from a thesis by Ali Sayyahi as a part of the Master’s degree in the field of Anatomical Sciences at the Neuroscience Research Center of Gorgan School of Medicine, Golestan University of Medical Sciences, Gorgan, Iran. The authors are thankful to the Research Deputy of the Golestan University of Medical Sciences for the financial support and also the Neuroscience Research Center for helping with the experiments.


The authors report no conflict of interest.


1. Abd-El-Fattah AA, El-Sawalhi MM, Rashed ER, El-Ghazaly MA. Possible role of vitamin E, coenzyme Q10 and rutin in protection against cerebral ischemia/reperfusion injury in irradiated rats. Int J Radiat Biol 2010; 86: 1070-1078.
2. Alzoubi KH, Khabour OF, Salah HA, Hasan Z. Vitamin E prevents high-fat high-carbohydrates diet-induced memory impairment: the role of oxidative stress. Physiol Behav 2013; 119: 72-78.
3. Anagnostaras SG, Murphy GG, Hamilton SE, Mitchell SL, Rahnama NP, Nathanson NM, Silva AJ. Selective cognitive dysfunction in acetylcholine M1 muscarinic receptor mutant mice. Nat Neurosci 2003; 6: 51-58.
4. Araujo JA, Studzinski CM, Milgram NW. Further evidence for the cholinergic hypothesis of aging and dementia from the canine model of aging. Prog Neuropsychopharmacol Biol Psychiatry 2005; 29: 411-422.
5. Arlt S, Beisiegel U, Kontush A. Lipid peroxidation in neurodegeneration: new insights into Alzheimer’s disease. Curr Opin Lipidol 2002; 13: 289-294.
6. Azami NS, Piri M, Oryan S, Jahanshahi M, Babapour V, Zarrindast MR. Involvement of dorsal hippocampal α-adrenergic receptors in the effect of scopolamine on memory retrieval in inhibitory avoidance task. Neurobiol Learn Mem 2010; 93: 455-462.
7. Babahajian A, Rasouli H, Katebi M, Sarveazad A, Soleimani M, Nobakht M. Effect of human chorionic gonadotropin and vitamine E on cellular density of CA1 hippocampal area, learning ability and memory, following ischemia – reperfusion injury in mice. J Gorgan Uni Med Sci 2014; 15: 23-28.
8. Baloyannis SJ. Mitochondrial alterations in Alzheimer’s disease. J Alzheimers Dis 2006; 9: 119-126.
9. Bassett CN, Neely MD, Sidell KR, Markesbery WR, Switt LL, Montine TJ. Cerebrospinal fluid lipoproteins are more vulnerable to oxidation in Alzheimer’s disease and are neurotoxic when oxidized ex vivo. Lipids 1999; 34: 1273-1280.
10. Billings LM, Oddo S, Green KN, McGaugh JL, Laferla FM. Intraneuronal Abeta causes the onset of early Alzheimer’s disease-related cognitive deficits in transgenic mice. Neuron 2005; 45: 675-688.
11. Bist R, Bhatt DK. The evaluation of effect of alpha-lipoic acid and vitamin E on the lipid peroxidation, gamma-amino butyric acid and serotonin level in the brain of mice (Mus musculus) acutely intoxicated with lindane. J Neurol Sci 2009; 276: 99-102.
12. Blanchard V, Moussaoui S, Czech C, Touchet N, Bonici B, Planche M, Canton T, Jedidi I, Gohin M, Wirths O, Bayer TA, Langui D, Duyckaerts C, Tremp G, Pradier L. Time sequence of maturation of dystrophic neurites associated with A deposits in APP/PS1 transgenic mice. Exp Neurol 2003; 184: 247-263.
13. Bonner TI, Buckley NJ, Young AC, Brann MR. Identification of a family of muscarinic acetylcholine receptor genes. Science 1987; 237: 527-532.
14. Bonner TI, Young AC, Bran MR, Buckley NJ. Cloning and expression of the human and rat m5 muscarinic acetylcholine receptor genes. Neuron 1988; 1: 403-410.
15. Brun A, Englund E. Regional pattern of degeneration in Alzheimer’s disease: neuronal loss and histopathological grading. Histopathology 1981; 5: 549-564.
16. Caulfield MP. Muscarinic receptors-characterization, coupling and function. Pharmacol Ther 1993; 58: 319-379.
17. Chen K, Zhang X, Wei Xp, Qu P, Liu Yx, Li Ty. Antioxidant vitamin status during pregnancy in relation to cognitive development in the first two years of life. Early Hum Dev 2009; 85: 421-427.
18. Chen W, Cheng X, Chen J, Yi X, Nie D, Sun X, Qin J, Tian M, Jin G, Zhang X. Lycium barbarum polysaccharides prevent memory and neurogenesis impairments in scopolamine-treated rats. PLoS One 2014; 9: e88076.
19. Ciobica A, Padurariu M, Bild W, Stefanescu C. Cardiovascular risk factors as potential markers for mild cognitive impairment and Alzheimer’s disease. Psychiatr Danub 2011; 23: 340-346.
20. Deb D, Bairy KL, Nayak V, Rao M. Comparative effect of lisinopril and fosinopril in mitigating learning and memory deficit in scopolamine-induced amnesic rats. Adv Pharmacol Sci 2015; 2015: 1-11.
21. Dysken MW, Sano M, Asthana S, Vertrees JE, Pallaki M, Llorente M, Love S, Schellenberg GD, McCarten JR, Malphurs J, Prieto S, Chen P, Loreck DJ, Trapp G, Bakshi RS, Mintzer JE, Heidebrink JL, Vidal-Cardona A, Arroyo LM, Cruz AR, Zachariah S, Kowall NW, Chopra MP, Craft S, Thielke S, Turvey CL, Woodman C, Monnell KA, Gordon K, Tomaska J, Segal Y, Peduzzi PN, Guarino PD. Effect of vitamin e and memantine on functional decline in Alzheimer disease: The TEAM-AD VA cooperative randomized trial. JAMA 2014; 311: 33-44.
22. Eftekharzadeh M, Nobakht M, Alizadeh A, Soleimani M, Hajghasem M, Kordestani Shargh B, Karkuki Osguei N, Behnam B, Samadikuchaksaraei A. The effect of intrathecal delivery of bone marrow stromal cells on hippocampal neurons in rat model of Alzheimer’s disease. Iran J Basic Med Sci 2015; 18: 520-525.
23. Eidi A, Eidi M, Mahmoodi G, Oryan S. Effect of vitamin E on memory retention in rats: possible involvement of cholinergic system. Eur Neuropsychopharmacol 2006; 16: 101-106.
24. Engin KN. Alpha-tocopherol: Looking beyond an antioxidant. Mol Vis 2009; 15: 855-860.
25. Farina N, Isaac MG, Clark AR, Rusted J, Tabet N. Vitamin E for Alzheimer’s dementia and mild cognitive impairment. Cochrane Database Syst Rev 2012; 11: CD002854.
26. Fata GL, Weber P, Mohajeri MH. Effects of vitamin E on cognitive performance during ageing and in Alzheimer’s disease. Nutrients 2014; 6: 5453-5472.
27. Felder CC, Bymaster FP, Ward J, DeLapp N. Therapeutic opportunities for muscarinic receptors in the central nervous system. J Med Chem 2000; 43: 4333-4353.
28. Fisher A. Cholinergic treatments with emphasis on m1 muscarinic agonists as potential disease-modifying agents for Alzheimer’s disease. Neurotherapeutics 2008; 5: 433-442.
29. Fukui K, Omoi NO, Hayasaka T, Shinnkai T, Suzuki S, Abe K, Urano S. Cognitive impairment of rats caused by oxidative stress and aging, and its prevention by vitamin E. Ann N Y Acad Sci 2002; 959: 275-284.
30. Gerber DJ, Sotnikova TD, Gainetdinov RR, Huang SY, Caron MG, Tonegawa S. Hyperactivity, elevated dopaminergic transmission, and response to amphetamine in M1 muscarinic acetylcholine receptor-deficient mice. Proc Natl Acad Sci 2001; 98: 15312-15317.
31. Giraldo E, Lloret A, Fuchsberger T, Vińa J. A and tau toxicities in Alzheimer’s are linked via oxidative stress-induced p38 activation: Protective role of vitamin E. Redox Biol 2014; 2: 873-877.
32. Grasby PM, Frith CD, Paulesu E, Friston KJ, Frackowiak RSJ, Dolan RJ. The effect of the muscarinic antagonist scopolamine on regional cerebral blood flow during the performance of a memory task. Exp Brain Res 1995; 104: 337-348.
33. Grimm MOW, Stahlmann CP, Mett J, Haupenthal VJ, Zimmer VC, Lehmann J, Hundsdörfer B, Endres K, Grimm HS, Hartmann T. Vitamin E: Curse or benefit in Alzheimer’s disease? A systematic investigation of the impact of -, - and -tocopherol on A generation and degradation in neuroblastoma cells. J Nutr Health Aging 2015; 19: 646-654.
34. Grodstein F, Chen J, Willett WC. High-dose antioxidant supplements and cognitive function in community-dwelling elderly women. Am J Clin Nutr 2003; 77: 975-984.
35. Grundman M. Vitamin E and Alzheimer disease: the basis for additional clinical trials. Am J Clin Nutr 2000; 71: 630s-636s.
36. Hamilton SE, Loose MD, Qi M, Levey AI, Hille B, McKnight GS, Idzerda RL, Nathanson NM. Disruption of the m1 receptor gene ablates muscarinic receptor-dependent M current regulation and seizure activity in mice. Proc Natl Acad Sci 1997; 94: 13311-13316.
37. Hasanein P, Kazemian Mahtaj A. Ameliorative effect of rosmarinic acid on scopolamine-induced memory impairment in rats. Neurosci Lett 2015; 585: 23-27.
38. Hasanein P, Shahidi S. Effects of combined treatment with vitamins C and E on passive avoidance learning and memory in diabetic rats. Neurobiol Learn Mem 2010; 93: 472-478.
39. Heneka MT, Sastre M, Dumitrescu-Ozimek L, Dewachter I, Walter J, Klockgether T, Van Leuven F. Focal glial activation coincides with increased BACE1 activation and precedes amyloid plaque deposition in APP [V717I] transgenic mice. J Neuroinflammation 2005; 2: 22.
40. Hodges Jr DB, Lindner MD, Hogan JB, Jones KM, Markus EJ. Scopolamine induced deficits in a battery of rat cognitive tests: comparisons of sensitivity and specificity. Behav Pharmacol 2009; 20: 237-251.
41. Hohmann CF, Potter ED, Levey AI. Development of muscarinic receptor subtypes in the forebrain of the mouse. J Comp Neurol 1995; 358: 88-101.
42. Jahanshahi M, Azami NS, Nickmahzar EG. Effect of scopolamine-based amnesia on the number of astrocytes in the rat’s hippocampus. Int J Morphol 2012; 30: 388-393.
43. Jahanshahi M, Nickmahzar EG, Babakordi F. The effect of Ginkgo biloba extract on scopolamine-induced apoptosis in the hippocampus of rats. Anat Sci Int 2013; 88: 217-222.
44. Jahanshahi M, Nickmahzar EG, Seif-hoseini S, Babakordi F, Moharreri A. Scopolamine reduces the density of M1 muscarinic neurons in rats’ hippocampus. Int J Morphol 2013; 31: 1227-1232.
45. Jahanshahi M, Nikmahzar E, Yadollahi N, Ramazani K. Protective effects of Ginkgo biloba extract (EGB 761) on astrocytes of rat hippocampus after exposure with scopolamine. Anat Cell Biol 2012; 45: 92-96.
46. Jahanshahi M, Sadeghi Y, Hosseini A. Estimation of astrocyte number in different subfield of rat hippocampus. Pak J Biol Sci 2006; 9: 1595-1597.
47. Jeong EJ, Lee KY, Kim SH, Sung SH, Kim YC. Cognitive-enhancing and antioxidant activities of iridoid glycosides from Scrophularia buergeriana in scopolamine-treated mice. Eur J Pharmacol 2008; 588: 78-84.
48. Jolitha AB, Subramanyam MVV, Devi SA. Age-related responses of the rat cerebral cortex: influence of vitamin E and exercise on the cholinergic system. Biogerontology 2009; 10: 53-63.
49. Karimi S, Jahanshahi M, Golalipour MJ. The effect of MDMA-induced anxiety on neuronal apoptosis in adult male rats’ hippocampus. Folia Biol (Praha) 2014; 60: 187-191.
50. Keltner NL, Zielinski AL, Hardin MS. Biological perspectives: Drugs used for cognitive symptoms of Alzheimer’s disease. Perspect Psychiatr Care 2001; 37: 31-34.
51. Khodamoradi N, Komaki A, Salehi I, Shahidi S, Sarihi A. Effect of vitamin E on lead exposure-induced learning and memory impairment in rats. Physiol Behav 2015; 144: 90-94.
52. Komaki A, Karimi SA, Salehi I, Sarihi A, Shahidi S, Zarei M. The treatment combination of vitamins E and C and astaxanthin prevents high-fat diet induced memory deficits in rats. Pharmacol Biochem Behav 2015; 131: 98-103.
53. Korbo L, Amrein I, Lipp HP, Wolfer D, Regeur L, Oster S, Pakkenberg B. No evidence for loss of hippocampal neurons in non-Alzheimer dementia patients. Acta Neurol Scand 2004; 109: 132-139.
54. Koscik RL, Lai HJ, Laxova A, Zaremba KM, Kosorok MR, Douglas JA, Rock MJ, Splaingard ML, Farrell PM. Preventing early, prolonged vitamin E deficiency: an opportunity for better cognitive outcomes via early diagnosis through neonatal screening. J Pediatr 2005; 147: 51-56.
55. Kril JJ, Patel S, Harding AJ, Halliday GM. Patients with vascular dementia due to microvascular pathology have significant hippocampal neuronal loss. J Neurol Neurosurg Psychiatry 2002; 72: 747-751.
56. Kwon SH, Kim HC, Lee SY, Jang CG. Loganin improves learning and memory impairments induced by scopolamine in mice. Eur J Pharmacol 2009; 619: 44-49.
57. Lee B, Park J, Kwon S, Park MW, Oh SM, Yeom MJ, Shim I, Lee HJ, Hahm DH. Effect of wild ginseng on scopolamine-induced acetylcholine depletion in the rat hippocampus. J Pharm Pharmacol 2010; 62: 263-271.
58. Lee HP, Zhu X, Casadesus G, Castellani RJ, Nunomura A, Smith MA, Lee HG, Perry G. Antioxidant approaches for the treatment of Alzheimer’s disease. Expert Rev Neurother 2010; 10: 1201-1208.
59. Levey AI. Immunological localization of m1-m5 muscarinic acetylcholine receptors in peripheral tissues and brain. Life Sci 1993; 52: 441-448.
60. Levey AI, Kitt CA, Simonds WF, Price DL, Brann MR. Identification and localization of muscarinic acetylcholine receptor proteins in brain with subtype-specific antibodies. J Neurosci 1991; 11: 3218-3226.
61. Lloret A, Badía MC, Mora NJ, Pallardó FV, Alonso MD, Vińa J. Vitamin e paradox in Alzheimer’s disease: It does not prevent loss of cognition and may even be detrimental. J Alzheimers Dis 2009; 17: 143-149.
62. Mahakizadeh S, Jahanshahi M, Haidari K, Shahbazi M. Dopamine receptors gene expression in male rat hippocampus after administration of MDMA (ecstasy). Int J Morphol 2015; 33: 301-308.
63. Marisco PC, Carvalho FB, Rosa MM, Girardi BA, Gutierres JM, Jaques JA, Salla AP, Pimentel VC, Schetinger MR, Leal DB, Mello CF, Rubin MA. Piracetam prevents scopolamine-induced memory impairment and decrease of NTPDase, 5’-nucleotidase and adenosine deaminase activities. Neurochem Res 2013; 38: 1704-1714.
64. Milgram NW, Head E, Zicker SC, Ikeda-Douglas CJ, Murphey H, Muggenburg B, Siwak C, Tapp D, Cotman CW. Learning ability in aged beagle dogs is preserved by behavioral enrichment and dietary fortification: a two-year longitudinal study. Neurobiol Aging 2005; 26: 77-90.
65. Miyakawa T, Yamada M, Duttaroy A, Wess J. Hyperactivity and intact hippocampus-dependent learning in mice lacking the M1 muscarinic acetylcholine receptor. J Neurosci 2001; 21: 5239-5250.
66. Moghadami S, Jahanshahi M, Sepehri H, Amini H. Gonadectomy reduces the density of androgen receptor-immunoreactive neurons in male rat’s hippocampus: testosterone replacement compensates it. Behav Brain Funct 2016; 12: 5.
67. Nagata K, Nakashima-Kamimura N, Mikami T, Ohsawa I, Ohta S. Consumption of molecular hydrogen prevents the stress-induced impairments in hippocampus-dependent learning tasks during chronic physical restraint in mice. Neuropsychopharmacology 2009; 34: 501-508.
68. Nathanson NM. Molecular properties of the muscarinic acetylcholine receptor. Annu Rev Neurosci 1987; 10: 195-236.
69. Navarro A, Bandez MJ, Lopez-Cepero JM, Gómez C, Boveris A. High doses of vitamin E improve mitochondrial dysfunction in rat hippocampus and frontal cortex upon aging. Am J Physiol Regul Integr Comp Physiol 2011; 300: R827-R834.
70. Nesaretnam K. Multitargeted therapy of cancer by tocotrienols. Cancer Lett 2008; 269: 388-395.
71. Nishida Y, Yokota T, Takahashi T, Uchihara T, Jishage K-i, Mizusawa H. Deletion of vitamin E enhances phenotype of Alzheimer disease model mouse. Biochem Biophys Res Commun 2006; 350: 530-536.
72. Padurariu M, Ciobica A, Hritcu L, Stoica B, Bild W, Stefanescu C. Changes of some oxidative stress markers in the serum of patients with mild cognitive impairment and Alzheimer’s disease. Neurosci Lett 2010; 469: 6-10.
73. Padurariu M, Ciobica A, Mavroudis I, Fotiou D, Baloyannis S. Hippocampal neuronal loss in the CA1 and CA3 areas of Alzheimer’s disease patients. Psychiatr Danub 2012; 24: 152-158.
74. Palozza P, Simone R, Picci N, Buzzoni L, Ciliberti N, Natangelo A, Manfredini S, Vertuani S. RETRACTED: Design, synthesis, and antioxidant potency of novel -tocopherol analogues in isolated membranes and intact cells. Free Radic Biol Med 2008; 44: 1452-1464.
75. Palozza P, Verdecchia S, Avanzi L, Vertuani S, Serini S, Iannone A, Manfredini S. Comparative antioxidant activity of tocotrienols and the novel chromanyl-polyisoprenyl molecule FeAox-6 in isolated membranes and intact cells. Mol Cell Biochem 2006; 287: 21-32.
76. Petersen RC, Thomas RG, Grundman M, Bennett D, Doody R, Ferris S, Galasko D, Jin S, Kaye J, Levey A, Pfeiffer E, Sano M, van Dyck CH, Thal LJ; Alzheimer’s Disease Cooperative Study Group.. Vitamin E and donepezil for the treatment of mild cognitive impairment. N Engl J Med 2005; 352: 2379-2388.
77. Power AE, McIntyre CK, Litmanovich A, McGaugh JL. Cholinergic modulation of memory in the basolateral amygdala involves activation of both m1 and m2 receptors. Behav Pharmacol 2003; 14: 207-213.
78. Puri V, Wang X, Vardigan JD, Kuduk SD, Uslaner JM. The selective positive allosteric M1 muscarinic receptor modulator PQCA attenuates learning and memory deficits in the Tg2576 Alzheimer’s disease mouse model. Behav Brain Res 2015; 287: 96-99.
79. Sano M, Ernesto C, Thomas RG, Klauber MR, Schafer K, Grundman M, Woodbury P, Growdon J, Cotman CW, Pfeiffer E, Schneider LS, Thal LJ. A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer’s disease. N Engl J Med 1997; 336: 1216-1222.
80. Schippling S, Kontush A, Arlt S, Buhmann C, Stürenburg HJ, Mann U, Müller-Thomsen T, Beisiegel U. Increased lipoprotein oxidation in Alzheimer’s disease. Free Radic Biol Med 2000; 28: 351-360.
81. Seifhosseini S, Jahanshahi M, Moghimi A, Aazami NS. The effect of scopolamine on avoidance memory and hippocampal neurons in male Wistar rats. Basic Clin Neurosci 2011; 3: 9-15.
82. Shichiri M, Yoshida Y, Ishida N, Hagihara Y, Iwahashi H, Tamai H, Niki E.-Tocopherol suppresses lipid peroxidation and behavioral and cognitive impairments in the Ts65Dn mouse model of Down syndrome. Free Radic Biol Med 2011; 50: 1801-1811.
83. Shideler KK, Yan J. M1 muscarinic receptor for the development of auditory cortical function. Mol Brain 2010; 3: 29.
84. Shinoe T, Matsui M, Taketo MM, Manabe T. Modulation of synaptic plasticity by physiological activation of M1 muscarinic acetylcholine receptors in the mouse hippocampus. J Neurosci 2005; 25: 11194-11200.
85. Shiozaki K, Iseki E, Hino H, Kosaka K. Distribution of M1 muscarinic acetylcholine receptors in the hippocampus of patients with Alzheimer’s disease and dementia with Lewy bodies – an immunohistochemical study. J Neurol Sci 2001; 193: 23-28.
86. Simic G, Kostovic I, Winblad B, Bogdanovic N. Volume and number of neurons of the human hippocampal formation in normal aging and Alzheimer’s disease. J Comp Neurol 1997; 379: 482-494.
87. Spires TL, Orne JD, SantaCruz K, Pitstick R, Carlson GA, Ashe KH, Hyman BT. Region-specific dissociation of neuronal loss and neurofibrillary pathology in a mouse model of tauopathy. Am J Pathol 2006; 168: 1598-1607.
88. Tagami M, Yamagata K, Ikeda K, Nara Y, Fujino H, Kubota A, Numano F, Yamori Y. Vitamin E prevents apoptosis in cortical neurons during hypoxia and oxygen reperfusion. Lab Invest 1998; 78: 1415-1429.
89. Tagliari B, Scherer EB, Machado FR, Ferreira AGK, Dalmaz C, Wyse ATS. Antioxidants prevent memory deficits provoked by chronic variable stress in rats. Neurochem Res 2011; 36: 2373-2380.
90. Takatsu H, Owada K, Abe K, Nakano M, Urano S. Effect of vitamin E on learning and memory deficit in aged rats. J Nutr Sci Vitaminol 2009; 55: 389-393.
91. Tayebati SK, Amenta F, El-Assouad D, Zaccheo D. Muscarinic cholinergic receptor subtypes in the hippocampus of aged rats. Mech Ageing Dev 2002; 123: 521-528.
92. Thomé GR, Spanevello RM, Mazzanti A, Fiorenza AM, Duarte MM, da Luz SC, Pereira ME, Morsch VM, Schetinger MR, Mazzanti CM. Vitamin E decreased the activity of acetylcholinesterase and level of lipid peroxidation in brain of rats exposed to aged and diluted sidestream smoke. Nicotine Tob Res 2011; 13: 1210-1219.
93. Van de Pol LA, Hensel A, Barkhof F, Gertz HJ, Scheltens P, Van Der Flier WM. Hippocampal atrophy in Alzheimer disease: age matters. Neurology 2006; 66: 236-238.
94. VanDeMark KL, Guizzetti M, Giordano G, Costa LG. The activation of M1 muscarinic receptor signaling induces neuronal differentiation in pyramidal hippocampal neurons. J Pharmacol Exp Ther 2009; 329: 532-542.
95. Wess J. Molecular biology of muscarinic acetylcholine receptors. Crit Rev Neurobiol 1996; 10: 69-99.
96. Wess J. Muscarinic acetylcholine receptor knockout mice: novel phenotypes and clinical implications. Annu Rev Pharmacol Toxicol 2004; 44: 423-450.
97. West MJ, Coleman PD, Flood DG, Troncoso JC. Differences in the pattern of hippocampal neuronal loss in normal ageing and Alzheimer’s disease. Lancet 1994; 344: 769-772.
98. Wirths O, Bayer TA. Neuron loss in transgenic mouse models of Alzheimer’s disease. Int J Alzheimers Dis 2010; 2010: 723782.
99. Wirths O, Breyhan H, Marcello A, Cotel MC, Brück W, Bayer TA. Inflammatory changes are tightly associated with neurodegeneration in the brain and spinal cord of the APP/PS1KI mouse model of Alzheimer’s disease. Neurobiol Aging 2010; 31: 747-757.
100. Yan BC, Park JH, Chen BH, Cho JH, Kim IH, Ahn JH, Lee JC, Hwang IK, Cho JH, Lee YL, Kang IJ, Won MH. Long-term administration of scopolamine interferes with nerve cell proliferation, differentiation and migration in adult mouse hippocampal dentate gyrus, but it does not induce cell death. Neural Regen Res 2014; 9: 1731-1739.
Copyright: © 2018 Mossakowski Medical Research Centre Polish Academy of Sciences and the Polish Association of Neuropathologists. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) License (http://creativecommons.org/licenses/by-nc-sa/4.0/), allowing third parties to copy and redistribute the material in any medium or format and to remix, transform, and build upon the material, provided the original work is properly cited and states its license.
Quick links
© 2019 Termedia Sp. z o.o. All rights reserved.
Developed by Bentus.
PayU - płatności internetowe