Rivastigmine interferes with the pharmacological activity of hydromethylthionine on presynaptic proteins in the line 66 model of frontotemporal dementia.

The negative interference of treatments between the acetylcholinesterase inhibitor rivastigmine and the tau aggregation inhibitor hydromethylthionine mesylate (HMTM) has been reported in Line 1 tau-transgenic mice, which overexpress a truncated species of tau protein that is found in the core of paired helical filaments in Alzheimer´s disease (AD). However, little is known about whether such interactions could affect synapses in mice overexpressing tau carrying pathogenic mutations. Here, we have used Line 66 (L66) mice which overexpress full-length human tau carrying the P301S mutation as a model in which tau accumulates in synapses.

Hydromethylthionine rescues synaptic SNARE proteins in a mouse model of tauopathies: Interference by cholinesterase inhibitors.

In clinical trials for Alzheimer's disease (AD), hydromethylthionine mesylate (HMTM) showed reduced efficacy when administered as an add-on to symptomatic treatments, while it produced a significant improvement of cognitive function when taken as monotherapy. Interference of cholinesterase inhibition with HMTM was observed also in a tau transgenic mouse model, where rivastigmine reduced the pharmacological activity of HMTM at multiple brain levels including hippocampal acetylcholine release, synaptosomal glutamate release and mitochondrial activity. Here, we examined the effect of HMTM, given alone or in combination with the acetylcholinesterase inhibitor, rivastigmine, at the level of expression of selected pre-synaptic proteins (syntaxin-1; SNAP-25, VAMP-2, synaptophysin-1, synapsin-1, α-synuclein) in brain tissue harvested from tau-transgenic Line 1 (L1) and wild-type mice using immunohistochemistry.

LETC inhibits α-Syn aggregation and ameliorates motor deficiencies in the L62 mouse model of synucleinopathy.

Alpha-Synuclein (α-Syn) aggregation is a pathological feature of synucleinopathies, neurodegenerative disorders that include Parkinson's disease (PD). Here, we explored the efficacy of N,N,N',N'-tetraethyl-10H-phenothiazine-3,7-diamine dihydrochloride (LETC), a protein aggregation inhibitor, on α-Syn aggregation. In both cellular models and transgenic mice, α-Syn aggregation was achieved by the overexpression of full-length human α-Syn fused with a signal sequence peptide.

Solubility of α-synuclein species in the L62 mouse model of synucleinopathy.

The accumulation of α-synuclein (α-Syn) into Lewy bodies is a hallmark of synucleinopathies, a group of neurological disorders that include Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Small oligomers as well as larger fibrils of α-Syn have been suggested to induce cell toxicity leading to a degenerative loss of neurones. A richer understanding of α-Syn aggregation in disease, however, requires the identification of the different α-Syn species and the characterisation of their biochemical properties.

A Meta-Analysis on Presynaptic Changes in Alzheimer's Disease.

Background: A key aspect of synaptic dysfunction in Alzheimer's disease (AD) is loss of synaptic proteins. Previous publications showed that the presynaptic machinery is more strongly affected than postsynaptic proteins. However, it has also been reported that presynaptic protein loss is highly variable and shows region- and protein-specificity.

Glutamatergic transmission and receptor expression in the synucleinopathy h-α-synL62 mouse model: Effects of hydromethylthionine.

The accumulation of alpha-synuclein (α-Syn) into Lewy bodies in cortical and subcortical regions has been linked to the pathogenesis of synucleinopathies such as Parkinson's disease (PD) and dementia with Lewy bodies (DLB). While there is a strong link between synuclein aggregates and the reduction in dopamine function in the emergence of PD, less is known about the consequences of α-Syn accumulation in glutamatergic neurons and how this could be exploited as a therapeutic target. Transgenic h-α-synL62 (L62) mice, in which synuclein aggregation is achieved through the expression of full-length human α-Syn fused with a signal sequence peptide, were used to characterise glutamatergic transmission using a combination of behavioural, immunoblotting, and histopathological approaches.

Proteomic Analysis of Hydromethylthionine in the Line 66 Model of Frontotemporal Dementia Demonstrates Actions on Tau-Dependent and Tau-Independent Networks.

Abnormal aggregation of tau is the pathological hallmark of tauopathies including frontotemporal dementia (FTD). We have generated tau-transgenic mice that express the aggregation-prone P301S human tau (line 66). These mice present with early-onset, high tau load in brain and FTD-like behavioural deficiencies.

Cu, Fe, and Zn isotope ratios in murine Alzheimer's disease models suggest specific signatures of amyloidogenesis and tauopathy.

Alzheimer's disease (AD) is characterized by accumulation of tau and amyloid-beta in the brain, and recent evidence suggests a correlation between associated protein aggregates and trace elements, such as copper, iron, and zinc. In AD, a distorted brain redox homeostasis and complexation by amyloid-beta and hyperphosphorylated tau may alter the isotopic composition of essential mineral elements. Therefore, high-precision isotopic analysis may reveal changes in the homeostasis of these elements.

Small sample sizes: A big data problem in high-dimensional data analysis.

In many experiments and especially in translational and preclinical research, sample sizes are (very) small. In addition, data designs are often high dimensional, i.e.

Differential compartmental processing and phosphorylation of pathogenic human tau and native mouse tau in the line 66 model of frontotemporal dementia.

Synapse loss is associated with motor and cognitive decline in multiple neurodegenerative disorders, and the cellular redistribution of tau is related to synaptic impairment in tauopathies, such as Alzheimer's disease and frontotemporal dementia. Here, we examined the cellular distribution of tau protein species in human tau overexpressing line 66 mice, a transgenic mouse model akin to genetic variants of frontotemporal dementia. Line 66 mice express intracellular tau aggregates in multiple brain regions and exhibit sensorimotor and motor learning deficiencies.

Mechanisms of Anticholinesterase Interference with Tau Aggregation Inhibitor Activity in a Tau-Transgenic Mouse Model.

Background: Symptomatic treatments of Alzheimer's Disease (AD) with cholinesterase inhibitors and/or memantine are relatively ineffective and there is a need for new treatments targeting the underlying pathology of AD. In most of the failed disease-modifying trials, patients have been allowed to continue taking symptomatic treatments at stable doses, under the assumption that they do not impair efficacy. In recently completed Phase 3 trials testing the tau aggregation inhibitor leuco-methylthioninium bis (hydromethanesulfonate) (LMTM), we found significant differences in treatment response according to whether patients were taking LMTM either as monotherapy or as an add-on to symptomatic treatments.

Multiplex LA-ICP-MS bio-imaging of brain tissue of a parkinsonian mouse model stained with metal-coded affinity-tagged antibodies and coated with indium-spiked commercial inks as internal standards.

Background: Immunohistochemistry techniques represent a powerful tool to detect and quantify disease related proteins. Improvements were accomplished by tagged antibodies using laser ablation and inductively coupled plasma mass spectrometry (LA-ICP-MS). However, these approaches are effected by day-to-variations due to instrumental drift.

Increased Cholinergic Response in α-Synuclein Transgenic Mice (h-α-synL62).

Pathological accumulation of misfolded α-synuclein (α-syn) in the brain plays a key role in the pathogenesis of Parkinson's disease, leading to neuronal dysfunction and motor disorders. The underlying mechanisms linking α-syn aggregations with neurotransmitter disturbance in Parkinson's brains are not well characterized. In the present study, we investigated transgenic mice expressing an aggregation-prone form of full-length human α-syn (h-α-synL62) linked to a signal sequence.

A Protein Aggregation Inhibitor, Leuco-Methylthioninium Bis(Hydromethanesulfonate), Decreases α-Synuclein Inclusions in a Transgenic Mouse Model of Synucleinopathy.

α-Synuclein (α-Syn) aggregation is a pathological feature of synucleinopathies, neurodegenerative disorders that include Parkinson's disease (PD). We have tested whether -tetramethyl-10-phenothiazine-3,7-diaminium bis(hydromethanesulfonate) (leuco-methylthioninium bis(hydromethanesulfonate); LMTM), a tau aggregation inhibitor, affects α-Syn aggregation and . Both cellular and transgenic models in which the expression of full-length human α-Syn (h-α-Syn) fused with a signal sequence peptide to promote α-Syn aggregation were used.

Sex differences in murine myocardium are not exclusively regulated by gonadal hormones.

Unlabelled: We investigated sex differences in cardiac protein patterns of intact and castrated mice using proteomics and 1D and 2D immunoblotting. To exclude differences concerning developmental aspects gonadectomy was conducted in mature mice at the age of three months. The main sex-related regulation in the protein pattern of the myocardium occurred for proteins involved in metabolic processes whereas only few proteins involved in other pathways underwent a regulation.

Alpha-Synuclein transgenic mice, h-α-SynL62, display α-Syn aggregation and a dopaminergic phenotype reminiscent of Parkinson's disease.

Alpha-Synuclein (α-Syn) accumulation is considered a major risk factor for the development of synucleinopathies such as Parkinson's disease (PD) and dementia with Lewy bodies. We have generated mice overexpressing full-length human α-Syn fused to a membrane-targeting signal sequence under the control of the mouse Thy1-promotor. Three separate lines (L56, L58 and L62) with similar gene expression levels, but considerably heightened protein accumulation in L58 and L62, were established.

Effects of oxidized and reduced forms of methylthioninium in two transgenic mouse tauopathy models.

Given the repeated failure of amyloid-based approaches in Alzheimer's disease, there is increasing interest in tau-based therapeutics. Although methylthioninium (MT) treatment was found to be beneficial in tau transgenic models, the brain concentrations required to inhibit tau aggregation in vivo are unknown. The comparative efficacy of methylthioninium chloride (MTC) and leucomethylthioninium salts (LMTX; 5-75 mg/kg; oral administration for 3-8 weeks) was assessed in two novel transgenic tau mouse lines.

Dietary genistein enhances phosphorylation of regulatory myosin light chain in the myocardium of ovariectomized mice.

There is evidence that isoflavones, such as genistein, can directly or indirectly improve lipid profile and lower blood pressure and hence exert cardiovascular protection. It is further believed, that genistein attenuates vascular contraction and thus vascular tone and blood pressure through altering the phosphorylation of the regulatory myosin light chain (MLC) probably via the myosin light chain kinase (MLCK) or the RhoA pathway. However, the direct role of genistein in the myocardium is poorly reviewed.

Endothelin-1 overexpression restores diastolic function in eNOS knockout mice.

Background: The cardiac nitric oxide and endothelin-1 (ET-1) systems are closely linked and play a critical role in cardiac physiology. The balance between both systems is often disturbed in cardiovascular diseases. To define the cardiac effect of excessive ET-1 in a status of nitric oxide deficiency, we compared left ventricular function and morphology in wild-type mice, ET-1 transgenic (ET(+/+)) mice, endothelial nitric oxide synthase knockout (eNOS(-/-)) mice, and ET(+/+)eNOS(-/-) mice.

Adaptation of proteomic techniques for the identification and characterization of protein species from murine heart.

Disturbed energy metabolism with impaired fatty acid oxidation, ATP synthesis and changing levels of contractile proteins has been observed during the development and manifestation of cardiovascular diseases, with the latter showing sexual differences in terms of onset, manifestation and progress. Estrogenic compounds, such as estrogens and phytoestrogens, are known to exert beneficial effects on several cardiovascular parameters. However, global studies implying the normal, non-failing myocardium are rare.

Dual feeding strategy for the production of alpha-amylase by Bacillus caldolyticus using complex media.

In this study, the objective was to investigate an exponential feeding strategy for fed-batch production of thermostable alpha-amylase (E.C. 3.