Project description:Amyloid-ß (Aß) plaques are pathological hallmarks of Alzheimer disease. However, the precise neuropathological changes that occur in brain in response to amyloid deposition are largely unknown. To study the molecular mechanism(s) responsible for Aß-mediated neuropathology, we performed a gene expression analysis on laser-microdissected brain tissue of Tg2576 mice compared to their littermate controls.
Project description:Extracellular senile plaques of amyloid beta (Abeta) are a pathological hallmark in brain of patients with Alzheimer`s Disease (AD). Abeta is generated by the amyloidogenic processing of the amyloid precursor protein (APP). Concomitant to Abeta load, AD brain is characterized by an increase in protein level and activity of the angiotensin-converting enzyme (ACE). ACE inhibitors are a widely used class of drugs with established benefits for patients with cardiovascular disease. However, the role of ACE and ACE inhibition in the development of Abeta plaques and the process of AD-related neurodegeneration is not clear since ACE was reported to degrade Abeta. To investigate the effect of ACE inhibition on AD-related pathomechanisms, we used Tg2576 mice with neuron-specific expression of APPSwe as AD model. From 12 months of age, substantial Abeta plaque load accumulates in the hippocampus of Tg2576 mice as a brain region, which is highly vulnerable to AD-related neurodegeneration. The effect of central ACE inhibition was studied by treatment of 12 month-old Tg2576 mice for six months with the brain penetrating ACE inhibitor captopril. At an age of 18 months, hippocampal gene expression profiling was performed of captopril-treated Tg2576 mice relative to untreated 18 month-old Tg2576 controls with high Abeta plaque load. As an additional control, we used 12 month-old Tg2576 mice with low Abeta plaque load. Whole genome microarray gene expression profiling revealed gene expression changes induced by the brain-penetrating ACE inhibitor captopril, which could reflect the neuro-regenerative potential of central ACE inhibition. Microarray gene expression profiling was performed of hippocampi isolated from aged, 18 month-old Tg2576 (APPSwe-transgenic) AD mice with high Abeta plaque load relative to age-matched Tg2576 mice, which were treated for 6 months with the centrally active ACE inhibitor captopril. Another study group consisted of 12 month-old Tg2576 mice with low Abeta plaque load. In total, three study groups were analyzed, i.e. (i) 18 month-old untreated Tg2576 mice with high Abeta plaque load, (ii) age-matched Tg2576 mice treated for 6 months with the brain-penetrating ACE inhibitor captopril (20 mg/kg body weight/day in drinking water), and (iii) untreated 12 month-old Tg2576 mice with low Abeta plaque load reflecting the time point when captopril treatment was initiated. Two biological replicates were made of each group, and total hippocampal RNA of four mice was pooled for one gene chip.
Project description:Olfaction is often deregulated in Alzheimer's disease (AD) patients, being also impaired in transgenic Tg2576 AD mouse model, which overexpress the Swedish mutated form of human amyloid precursor protein (APP). However, little is known about the molecular mechanisms that accompany the neurodegeneration of olfactory structures in Tg2576 mice. For that, we have applied proteome- and transcriptome-wide approaches to probe molecular disturbances in the olfactory bulb (OB) dissected from Tg2576 mice (2, and 6 months of age) respect to age-matched wild-type (WT) littermates.
Project description:Amyloid-M-CM-^_ (AM-CM-^_) plaques are pathological hallmarks of Alzheimer disease. However, the precise neuropathological changes that occur in brain in response to amyloid deposition are largely unknown. To study the molecular mechanism(s) responsible for AM-CM-^_-mediated neuropathology, we performed a gene expression analysis on laser-microdissected brain tissue of Tg2576 mice compared to their littermate controls. 4 samples; 2 biological replicates of each condition = 2 transgenic versus 2 non-transgenic mice; double amplification of total RNA; only Cy3; no dye-swaps
Project description:While mouse models of ß-amyloidopathy recapitulate aspects of Alzheimer's disease pathology, including plaque formation and synapse loss, most progress at a speed such that outcomes are studied in the mature mouse, rather than the aged mouse. Here we investigated Aß-dependent changes to astrocytes in a knock-in model of ß-amyloidopathy (APP NL-F) that is known to progress more slowly.
Project description:Extracellular senile plaques of amyloid beta (Abeta) are a pathological hallmark in brain of patients with Alzheimer`s Disease (AD). Abeta is generated by the amyloidogenic processing of the amyloid precursor protein (APP). Concomitant to Abeta load, AD brain is characterized by an increase in protein level and activity of the angiotensin-converting enzyme (ACE). ACE inhibitors are a widely used class of drugs with established benefits for patients with cardiovascular disease. However, the role of ACE and ACE inhibition in the development of Abeta plaques and the process of AD-related neurodegeneration is not clear since ACE was reported to degrade Abeta. To investigate the effect of ACE inhibition on AD-related pathomechanisms, we used Tg2576 mice with neuron-specific expression of APPSwe as AD model. From 12 months of age, substantial Abeta plaque load accumulates in the hippocampus of Tg2576 mice as a brain region, which is highly vulnerable to AD-related neurodegeneration. The effect of central ACE inhibition was studied by treatment of 12 month-old Tg2576 mice for six months with the brain penetrating ACE inhibitor captopril. At an age of 18 months, hippocampal gene expression profiling was performed of captopril-treated Tg2576 mice relative to untreated 18 month-old Tg2576 controls with high Abeta plaque load. As an additional control, we used 12 month-old Tg2576 mice with low Abeta plaque load. Whole genome microarray gene expression profiling revealed gene expression changes induced by the brain-penetrating ACE inhibitor captopril, which could reflect the neuro-regenerative potential of central ACE inhibition.
Project description:Olfaction is often deregulated in Alzheimer´s disease (AD) patients, being also impaired in transgenic Tg2576 AD mouse model, which overexpress the Swedish mutated form of human amyloid precursor protein (APP). However, little is known about the molecular mechanisms that accompany the neurodegeneration of olfactory structures in Tg2576 mice. For that, we have applied proteome-wide approaches to probe molecular disturbances in the olfactory bulb (OB) dissected from Tg2576 mice respect to age matched wild-type littermates (2 and 6 months of age).
Project description:Liquid chromatography mass spectrometry was used to study tumor matrisome from laser capture microdissected FFPE tissue sections of human neck and squamous cell carcinoma (HnSCC) xenograft grown in mouse.