alzheimers-disease

Laursen B, Mork A, Plath N, Kristiansen U, Bastlund JF (2013) Cholinergic degeneration is associated with increased plaque deposition and cognitive impairment in APPswe/PS1dE9 mice. Behav Brain Res 240:146-152. doi: 10.1016/j.bbr.2012.11.012

Summary: Extracellular plaques containing amyloid β-peptides (Aβ) and cholinergic dysfunction are two of the main hallmarks of Alzheimer’s disease. Using a transgenic mouse line that displays an age-related increase in plaque deposition, the authors examined the relationship between cholinergic degeneration and Aβ overexpresssion. Mice received 0.9-μg bilateral icv injections of mu p75-SAP (Cat. #IT-16). Working memory was significantly impaired in lesioned mice with plaques, and the plaque burden was increased as compared to wild-type mice that also received a lesion.

Related Products: mu p75-SAP (Cat. #IT-16)

Brayda-Bruno L, Mons N, Yee BK, Micheau J, Abrous DN, Nogues X, Marighetto A (2013) Partial loss in septo-hippocampal cholinergic neurons alters memory-dependent measures of brain connectivity without overt memory deficits. Neurobiol Dis 54:372-381. doi: 10.1016/j.nbd.2013.01.010

Summary: The authors examined whether partial degeneration of septo-hippocampal neurons alters brain activity patterns even without overt memory loss. Mice received 45 ng of mu p75-SAP (Cat. #IT-16) into the medial septal area. Lesioned animals had significantly altered functional activities in the brain, despite lack of an overt behavioral deficit. Some changes observed are also altered with the initial signs of Alzheimer’s disease.

Related Products: mu p75-SAP (Cat. #IT-16)

Szigeti C, Bencsik N, Simonka AJ, Legradi A, Kasa P, Gulya K (2013) Long-term effects of selective immunolesions of cholinergic neurons of the nucleus basalis magnocellularis on the ascending cholinergic pathways in the rat: A model for Alzheimer’s disease. Brain Res Bull 94C:9-16. doi: 10.1016/j.brainresbull.2013.01.007

Summary: 192-IgG-SAP (Cat. #IT-01) has been used extensively to generate models of Alzheimer’s disease in rats. In this work, the authors detailed the time course of neuronal loss with an eye on potential recovery from the lesion. The nucleus basalis magnocellularis of rats was injected with 75 ng of 192-IgG-SAP (Cat. #IT-01) and long-term changes were tracked by immunohistochemistry. While some acetylcholinesterase neurons, considered cholinoceptive, were lost, choline acetyltransferase (cholinergic) neurons sustained a massive irreversible reduction in number.

Related Products: 192-IgG-SAP (Cat. #IT-01)

Hamlin AS, Windels F, Boskovic Z, Sah P, Coulson EJ (2013) Lesions of the basal forebrain cholinergic system in mice disrupt idiothetic navigation. PLoS One 8(1):e53472. doi: 10.1371/journal.pone.0053472

Summary: Alzheimer’s disease patients perform poorly on spatial navigation tests requiring either distal cues (allothetic) or body-centered cues (idiothetic). The authors used 0.2 μg bilateral infusions of mu p75-SAP (Cat. #IT-16) into the lateral ventricles of mice to examine the hypothesis that the cholinergic medial septo-hippocampal circuit is important for idiothetic navigation. Rabbit IgG-SAP (Cat. #IT-35) was used as a control. Lesioned animals were similar to controls in contextual fear conditioning, spatial working memory, as well as several other parameters. But exploratory behavior requiring idiothetic signals was very disorganized, indicating that cholinergic cells are vital to idiothetic navigation.

Related Products: mu p75-SAP (Cat. #IT-16), Rabbit IgG-SAP (Cat. #IT-35)

Kerbler GM, Hamlin AS, Pannek K, Kurniawan ND, Keller MD, Rose SE, Coulson EJ (2013) Diffusion-weighted magnetic resonance imaging detection of basal forebrain cholinergic degeneration in a mouse model. Neuroimage 66C:133-141. doi: 10.1016/j.neuroimage.2012.10.075

Summary: The authors examined the effectiveness of diffusion MRI using diffusion tensor imaging (DTI) and probabilistic tractography in detecting cholinergic loss in a mouse model. Mice received bilateral 0.2-μg icv injections of mu p75-SAP (Cat. #IT-16). Rabbit IgG-SAP (Cat. #IT-35) was used as control. The animals were then examined using DTI. The data indicate that DTI is a valid technique for assessment of cholinergic loss in septo-hippocampal tracts as a result of Alzheimer’s disease.

Related Products: mu p75-SAP (Cat. #IT-16), Rabbit IgG-SAP (Cat. #IT-35)

Ortiz-Barajas O, Ramos-Rodriguez J, Berrocoso E, Garcia Alloza M (2012) Limited effect of serotonergic denervation on beta-amyloid and cognitive impairment in APPswe/PS1dE9 mice. Neuroscience 2012 Abstracts 751.12. Society for Neuroscience, New Orleans, LA.

Summary: Alzheimer’s Disease (AD) is a neurodegenerative disease characterized by progressive cognitive and memory impairment. Amyloid-beta (Aβ) deposition, as senile plaques (SP), seems to play a key role in the development and progression of the illness. Moreover SP tend to accumulate in cortex and hippocampus, relevant areas in learning and memory. On the other hand neuronal loss is the pathological feature that best correlates with duration and severity of the illness and at present animal available animal models hardly reproduce the complexity of the disease. We have previously seen that selective cortical and hipocampal cholinergic denervation, using murine p-75 saporin, may worsen cognitive abilities in APPswe/PS1dE9 mice as well as increase SP deposition in denervated areas. In the present work we lesioned 7 months old APPswe/PS1dE9 mice with 1 µl of 5,7-dyhidroxytiptamine (0.16 µg/µl) injected in the raphe nucleus (RN). In order to guarantee selective removal of cortical and hipocampal serotonergic inervation, and protect noardernergic and dopaminergic neurons, animals were i.p. injected with desipramine and nomifensine before surgery. We observed a clear reduction of tryptophan hydroxilase staining in the RN. In the Morris water maze test we observed learning and memory impairment in APPswe/Ps1dE9 mice, without a synergistic effect of the serotonergic lesion. When we assessed SP deposition we did not observe a significant increase of SP in cortex or hipocampus 14 days after the lesion, as we observed after selective cholinergic denervation. Altogether our data suggest that cognitive impairment and induced SP depositioin observed after cholinergic denervation is not achieved when serotonergic system is affected, supporting a selective effect mediated by different neurotransmitter systems. Acknowledgements: MG-A: RYC-2008-02333, ISCIII-Subdirección General de Evaluación y Fomento de la Investigación (PS09/00969), Fundación Dr. Eugenio Rodriguez Pascual, Junta Andalucia Excelencia (CTS-7847).

Related Products: mu p75-SAP (Cat. #IT-16)

Jeong D, Lee J, Lee S, Kim S, Chang J (2012) Spatial memory facilitation by electrical stimulation of the medial septum in rats. Neuroscience 2012 Abstracts 851.01. Society for Neuroscience, New Orleans, LA.

Summary: Recently, deep brain stimulation has been used to treat various neurological disorders. Some studies support that DBS can be a strategy to treat Alzheimer’s disease. The aim of this study was to evaluate the effect of electrical stimulation in the medial septum using rat model mimicking basal forebrain cholinergic deficits of Alzheimer’s disease. Four experimental groups were composed of normal, lesion, lesion + implantation and lesion + stimulation. 192 IgG-saporin (Selective cholinergic toxin, 8ul of 0.63ug/ul) were bilaterally injected into the lateral ventricle. Electrode was stereotactically implanted into the left medial septum (AP +0.6, ML 0.16, DV -6). Stimulation parameters are 50Hz, 120us pulse width and 1 volt. One week after implantation, Stimulation started for 2 weeks. Two weeks after surgery, water maze was performed for 1 week and rats were sacrificed immediately after behavioral test. Features were verified by immunochemistry and AChE assay. During the training trials, latencies of lesion and implantation significantly increased in day3 and day4. In contrast, latency of stimulation group had no differences as compared to normal group but it decreased significantly when compared to lesion group in day4. In the probe test, lesion group had decreases in time in target quadrant, time in platform zone and the number of platform crossing. Although they did not perform as normal group, stimulation group showed tendency of recovery. IHC and AChE assay are ongoing. Spatial memory is associated with hippocampus. We had expected activation of hippocampus by stimulation of the medial septum. We confirmed that stimulation of the medial septum facilitates acquisition and recall of spatial memory. Currently we are studying the effects of medial septal stimulation on the hippocampus.

Related Products: 192-IgG-SAP (Cat. #IT-01)

Anderson ML, Govindaraju KP, Shors TJ (2012) Acetylcholine and Learning: Are they related and does it matter for associating events across time?. Neuroscience 2012 Abstracts 600.12. Society for Neuroscience, New Orleans, LA.

Summary: Decades ago, acetylcholine was considered intrinsic to processes related to attention and/or learning and memory. Much of this was based on its presumed role in dementia associated with Alzheimer’s disease. However, in the last decade or so, this relationship has been questioned and with good reason (Parent & Baxter, 2004). That said, only a few studies have addressed the involvement of acetylcholine in tasks that require an animal to associate stimuli separated in time, such as trace eyeblink conditioning. This type of task is dependent on the hippocampus and is severely disrupted in both patients with Alzheimer’s disease and animal models of the disorder (Kishimoto, 2012; Waddell et al., 2008; Woodruff-Pak & Papka, 1996). In the present study, we hypothesized that animals with minimal Ach input to both hippocampi would not learn whereas those with input into one hippocampus could. The immunotoxin 192 IgG-Saporin was infused into the MSDB to selectively kill cholinergic neurons in Sprague-Dawley rats and then trained with either delay or trace eyeblink conditioning. Delay conditioning requires that the stimuli during training are contiguous in time and is not dependent on the hippocampus. Animals were given 200 trials for four days for 800 trials in total. A complete bilateral MSDB-cholinergic lesion was considered complete if the number of neurons that express choline acetyltransferase was reduced by 75 %. A bilateral lesion of this magnitude prevented early acquisition of the trace response (p<.05). Indeed, none of the animals so far trained reached a learning criterion of 60 % CRs during any session of training. In contrast, animals with a loss of ACh in just one hemisphere were able to learn the CR. Furthermore, preliminary data suggest delay conditioning was unaffected by the loss of ACh from the septum. Finally, animals with half the number of cholinergic neurons were still able to learn trace eyeblink conditioning regardless of whether the damage was bilateral or unilateral. Thus, it would appear that the progressive loss of ACh coincides with the loss of learning potential, especially when that learning requires associations across time. This approach and the experimental results may model the progressive nature of Alzheimer’s disease, in which the loss of neuronal function is slow but cumulative.

Related Products: 192-IgG-SAP (Cat. #IT-01)

Nichols TW (2012) Emerging roles of pathogens in alzheimer’s and moderate magnetic field therapy: dc emf 0.5 tesla. Neuroscience 2012 Abstracts 438.10. Society for Neuroscience, New Orleans, LA.

Summary: Chronic spirochetal infection can cause slowly progressive dementia, cortical atrophy and amyloid deposition in the atrophic form of general paresis. There is a significant association between Alzheimer disease (AD) and various types of spirochete (including the periodontal pathogen Treponemas and Borrelia burgdorferi), and other pathogens such as Chlamydophyla pneumoniae and herpes simplex virus type-1 (HSV-1). (Miklossy 2011 Exp Rev Mol Med) Miklossy’s lab exposed mammalian glia & neuronal cells in vitro to Borrelia burgdorferi spirochetes and bacterial lipopolysaccharides (LPS). Morphological changes analogous to amyloid deposits were observed at 2-8 wks exposure. Increased levels of ß-amyloid precursor protein and hyperphosphorylated tau were detected by WB.The frequency of spirochetes is significantly higher in the brains of Alzheimer patients compared to controls.The statistical analysis is based on the cumulative data of the literature. (P=1.5×10-17,OR=20, 95%CI=8-60! Seven out of ten brains from the Harvard McLean Brain bank were positive for Borrelia DNA. Alan Mac Donald MD. “Borrelia Infection is the root cause of at least 70% of Alzheimer’s disease, based on the detection of positive In situ DNA hybridization results in the cytoplasic GVB sites of hippocampal neurons ( with no positive signals detected in the nucleus) for flagellin B DNA sequences of Borrelia burgdorferi.” Antibiotics in Alzheimer’s disease: A randomized controlled trial of doxycycline and rifampin for patients with Alzheimer’s disease 2004. Cognitive decline was statically improved in treatment over placebo. Minocycline protects basal forebrain cholinergic neurons from mu p 75-saporin immunotoxic lesioning 2004 in animal model. Minocycline attenuates neuronal cell death and improves cognitive impairment in Alzheimer’s disease models 2007. Minocycline does not affect amyloid ß phagocytosis by human microglia cells. (Minocycline attenuates the release of TNF-α by human microglia upon exposure to Abeta, SAP and C1q) 2007. Moderate Magnetic Field Therapy (0.5 Tesla) in 15 Alzheimer’s patients. Results; Cognition Improved: group average hours = 184.Mechanism hypothesis: Overview of crosstalk between SMF & IL-6.Wang, Z, Sarje A, Che PL, Yarema K. Moderate strength (0.23-0.28T) static magnetic fields (SMF) modulate signaling and differentiation in human embryonic cells. BMC Genomic 2009;10:356

Related Products: mu p75-SAP (Cat. #IT-16)

Lee J, Jeong D, Chang J (2012) The effects of basal forebrain cholinergic neuron of recognition tests. Neuroscience 2012 Abstracts 345.10. Society for Neuroscience, New Orleans, LA.

Summary: The cholinergic neurons of the Medial septum and the basal nucleus areas of the basal forebrain project to the frontal cortex and the Hippocampus, and degeneration of the cholinergic basal forebrain neuron is a common feature of Alzheimer’s disease(AD) and vascular dementia and it has been correlated with cognitive decline. This research studied to verify the effects of cholinergic neuron in basal forebrain and the role of hippocampus and frontal cortex on recognition through recognition test and immunohistochemistry after damaging cholinergic neuron of the basal forebrain by intraventricular injection of 192 IgG-saporin. 192 IgG-saporin of 8ul (0.63ug/ul) was injected to the bilateral lateral ventricle of rats. After 2 weeks, Novel object recognition (NOR) test and Object in place (OIP) test was conducted to elucidate damage of cholinergic neuron. After completing the behavioral test, the ChAT cholinergic neuron in the brain was ascertained to confirm with immunohistochemistry if cholinergic neuron was damaged. In NOR test, the lesion group with 192 IgG-saporin showed 10% lower novel object preference than normal group. In OIP test, the normal group showed 50% novel object preference and the lesion group with 192 IgG-saporin showed 30% novel object preference in an hour delay test. On the other hand, the normal group and the lesion group with 192 IgG-saporin shoed 33% and 35% novel object preference respectively in a day delay test. However, this rate is not that significant value enough to elucidate behavioral difference between normal group and lesion group. In immunohistochemistry, the number of cholinergic neuron was remarkably decreased in basal forebrain. According to both of the behavioral tests, lesion group seem to less remember novel object than normal group. Also, they searched less the novel object that changed its location than normal group in the short term condition. However, there was no significant difference in the long term condition. These results suggest that the lesion with 192 IgG-saporin can damage spatial working memory.In the Immunohistochemistry result of the lesion condition, cholinergic input to hippocampus in basal forebrain affects recognition. However, the effect is not so essential.

Related Products: 192-IgG-SAP (Cat. #IT-01)