Abnormal Protein Deposition Research Articles

On Multicell-Interaction Chip: In Situ Observing the Interactions between the Astrocytes with Lysosomal Dysfunction and BBB Cells.

Lysosomes in astrocytes play vital roles in toxic protein degradation in the brain. Lysosomal dysfunction can lead to abnormal protein deposits, which further induce damage to neurons and the blood-brain barrier (BBB), and thereby affect the interaction between the nervous and vascular systems. Therefore, investigating the interactions between astrocytes with lysosomal dysfunction and BBB cells is of significant importance. However, the lack of effective in vitro models hinders the study of this complex system. Herein, an 8-well arrayed microfence multicell interculture chip (AMMIC) with a hydrophilically optimized surface is introduced for investigating the interactions between astrocytes and BBB cells. Then, a novel lysosome-targeted photosensitizer, IVQ-2Br, is synthesized for inducing controllable oxidative stress damage in the lysosomes of astrocytes. By the combination of the 8-well AMMIC and IVQ-2Br, a model for studying the interactions between astrocytes with lysosomal dysfunction and BBB cells has been constructed. Particularly, severe secondary injuries to BBB cells brought about by oxidative stress, including alterations in cell morphology and activity as well as notable DNA damage, are in situ observed on the 8-well AMMIC. The mediators involved in this oxidative stress injury-mediated intercellular communication are validated to be reactive oxygen species (ROS) and exosomes. This work not only presents an in vitro modeling method for studying cell-cell interactions but also demonstrates the potential of in vitro models constructed through the integration of complex microfluidic chip techniques and photosensitizers for advancing biomedical research.

Inhibition of Bone Morphogenetic Protein Signaling Prevents Tau Pathology in iPSC Derived Neurons and PS19 Mice.

Many neurodegenerative disorders share a common pathologic feature involving the deposition of abnormal tau protein in the brain (tauopathies). This suggests that there may be some shared pathophysiologic mechanism(s). The largest risk factor for the majority of these disorders is aging, suggesting involvement of the aging process in the shared pathophysiology. We test the hypothesis that an increase in bone morphogenetic protein (BMP) signaling that occurs during aging contributes to the onset and progression of tauopathies. Human induced pluripotent stem cell (iPSC)-derived neurons from patients with Alzheimer's disease (AD) were used to investigate the effects of BMP signaling on tau phosphorylation and release and the mechanisms underlying these effects. Wildtype mice were used to examine effects of BMP signaling in vivo. P301S (PS19) mice were examined for the effects of BMP signaling in a model of tauopathy. Here, we show that BMP signaling, mediated by non-canonical p38 signaling, increases tau phosphorylation and release of p-tau in human iPSC-derived AD neurons. Further, there is an interaction between BMP signaling and apolipoprotein E4 (ApoE4) that significantly increases tau phosphorylation and release compared with ApoE3 neurons. Inhibiting BMP signaling reduces the changes in tau in the cultured human neurons, and it limits tau pathology and prevents cognitive decline in PS19 mice. Our study suggests that the age-related increase in BMP signaling may participate in the onset and progression of tau pathology. Thus, therapeutic interventions that reduce BMP signaling in the aging brain could potentially slow or prevent development of diseases involving tau hyperphosphorylation. ANN NEUROL 2024.

Exploring the Therapeutic Role of Rab8a in 4R‐Tauopathy

AbstractBackgroundProgressive Supranuclear Palsy (PSP) and Corticobasal Degeneration (CBD) are characterized by abnormal aggregation and deposition of tau proteins in neurons and supporting brain cells. The underlying pathophysiology of these 4R‐tauopathy disorders remains unclear. In Alzheimer’s disease (AD), a related tauopathy, vesicle trafficking deficits, and impaired protein clearance are observed early in disease progression. Rab GTPase proteins play an important role in vesicular trafficking, endocytosis, and endosomal‐lysosomal pathways and have been implicated in Parkinson’s disease (PD) and AD pathology. In AD, the normal function of specific Rab proteins is disrupted early and may contribute to abnormal tau accumulation and neurofibrillary tangle formation. Among various Rabs GTPases, Rab8a’s role in AD pathology is explored and shown to accelerate endocytosed Aβ trafficking to the lysosomes and has expression found to decrease in PS1 mutant expressing cells. In contrast, Rab proteins, including Rab8a, and their contribution to 4R tauopathies such as PSP and CBD are little known.MethodIn the postmortem tissues from AD, PSP, and CBD, Rab8a protein expression was determined using western blot analysis. Further, human neuroglioma H4 cells were co‐transfected with wild‐type or mutant Rab8a and 4R0N or self‐aggregating mutant tau[P301L/S320F].ResultIn H4 cells, overexpression of Rab8a resulted in a marked reduction of total and phospho‐tau. The reduction in total and p‐tau was not observed with mutant (non‐functional) Rab8a overexpression. The Rab8a protein expression was found to be decreased in postmortem brain tissues (frontal cortex) from PSP and CBD compared to control tissue.ConclusionThe study demonstrates the Rab GTPase, Rab8a, expression in neuropathological tissues from 4R‐tauopathy disorders (PSP and CBD) and AD. In addition, the study provides evidence that Rab8a may regulate tau and associated pathology.

Higher detectability of amyloid with phenol Congo red compared with alkaline Congo red.

Amyloidosis is a heterogeneous group of conditions associated with tissue deposition of insoluble abnormal proteins that damage vital organs. Early diagnosis, when the deposits are minimal, determines the prognosis and requires histological confirmation. The commonly adopted gold standard technique is alkaline Congo red (ACR) staining, though its sensitivity is limited. There is a need for a simple and inexpensive screening method offering a better chance of detecting minimal amyloid deposits. The aim of this study was to compare amyloid detectability with ACR and phenol Congo red (PHCR) staining techniques for early detection of minimal deposits. We assessed 452 tissue specimens (including adipose tissue, gastrointestinal mucosa, labial salivary gland, myocardium, and bone marrow) from 425 patients with clinically suspected systemic or local amyloidosis, which had been sent to the Pathology Laboratory of the National Institute of Geriatrics, Rheumatology and Rehabilitation in Warsaw. Adjacent sections from each specimen were stained with ACR and PHCR. If amyloid was detected, immunohistochemical typing was conducted. The consistency of the two staining methods was expressed as Cohen's κ coefficient. A total of 169 tissue specimens (37%) yielded positive readings, with 93 cases ACR(+) and PHCR(+); 75 cases ACR(-) and PHCR(+), and 1 case ACR(+) and PHCR(-). The percentage agreement between the staining methods was 83%, with the Cohen's κ coefficient value of 0.60 (95% CI: 0.52-0.69), which corresponds to moderate agreement according to Fleiss. Additional immunohistochemical amyloid typing, conducted in ACR(-) and PHCR(+) specimens, yielded conclusive results in 82% of cases. The use of PHCR staining as a screening method in suspected amyloidosis improves amyloid (light chain, transthyretin, and amyloid A protein) detectability in various tissues. The PHCR staining specificity should be verified via electron microscopy and/or mass spectrometry.

Pathophysiology of Normal Pressure Hydrocephalus

The current perspective for the pathophysiology of normal pressure hydrocephalus is focusing on stiffness of the central nervous tissue, especially on a type of cerebrovascular disorder. Rigid intracranial vessels and tissues derived by either vascular risk factors or aging may lead into impaired dynamics of the cerebrospinal fluid such as increased pulsatility and decreased absorption of the cerebrospinal fluid. Enlarged ventricle may result in a decrease of blood perfusion in brain parenchyma, and in turn global hypoxia and neuro-inflammation along with a breakdown of the blood-brain-barrier. Deterioration of the glymphatic pathway, the crucial disposal pathway of the waste product of the brain, also might contribute to the irreversible injury of the nervous tissue by deposition of abnormal toxic proteins including amyloid beta. Of note, the pathophysiology of the normal pressure hydrocephalus is moving to a type of cerebrovascular disorder instead of the etiology of idiopathic.

Delays in diagnosis and treatment initiation of ATTR cardiac amyloidosis: a real-world data analysis

Abstract Introduction Cardiac amyloidosis (CA) is a serious condition characterized by the accumulation of abnormal protein deposits in the heart muscle, leading to functional impairments and, ultimately, heart failure. Transthyretin amyloid cardiomyopathy (ATTR-CM) is the most common form encountered in CA diagnosis with previously underestimated prevalence. ATTR-CM poses a diagnostic challenge, with a substantial number of cases diagnosed late and at advanced stages. The availability of specific pharmacological treatment using the transthyretin-stabilizer tafamidis further emphasizes the need for timely diagnosis. Here, we aim to assess delays in diagnosis and initiation of therapy in a real-world collective of patients with ATTR-CM. Methods All individuals diagnosed from 01/2018 to 05/2023 with ATTR-CM at our university hospital, Germany, were systematically assessed for eligibility in this study. Specifically, we enrolled patients who were undergoing transthyretin stabilizer therapy. The investigation aimed to determine the duration, in days, from the initial suspicion of heart disease to the definitive diagnosis of ATTR-CM. It was also investigated whether the diagnosis of ATTR-CM was made more quickly over time as awareness increased. Additionally, the study assessed the time elapsed until patients received pharmacological therapy following the confirmed diagnosis. The study was approved by the local ethics committee (23-11500-BO). Results After screening of 194 consecutive patients, 154 were included in the analysis, while 40 patients were excluded due to insufficient records. The results of this study reveal that a median of 300 (113-962) days elapsed from the initial suspicion of amyloidosis to the final confirmation. Initial indications of CA often presented as nonspecific symptoms such as unclear dyspnea (16.2% n=25), abnormal echocardiography (75.3% n=116), or, in rare cases, incidental findings (8.4% n=13). Following the diagnosis, an additional median of 84 (46-163.5) days passed before the first prescription of a transthyretin stabilizer. To assess an improvement of ATTR-CM diagnosis over time, we stratified the data into tertiles by date of first diagnosis. The results showed a gradually decrease in medium time to diagnosis of 466 (181-1035) days in the earliest tertile (2018-2019) to 389 (141-1508) days in the most recent tertile (2022-2023) (p<0.001). Conclusion This study shows a major healthcare deficit and underscores the medical need for improved screening procedures and diagnostic modalities to expedite the timely diagnosis of CA, as early identification of the condition is crucial for enhancing the quality of life for patients and preventing life-threatening complications.

A Hydroxyquinoline Polymer with Excellent Amyloidosis Inhibition and Protein Delivery Ability to Combat Amyloid-β-Mediated Neurotoxicity.

The accumulation of abnormal protein deposits known as amyloid-β (Aβ) plaques contributes to the development and progression of Alzheimer's disease. Aggregated Aβ exacerbates oxidative stress by stimulating the production of reactive oxygen species (ROS) in a detrimental feedback loop. 8-Hydroxyquinoline (8-HQ) is recognized for its ability to inhibit or reverse Aβ aggregation and reduce neurotoxicity. Here, an 8-HQ-based polymer, DHQ, was developed to combat Aβ-mediated neurotoxicity by delivering an antioxidant enzyme. DHQ efficiently delivers superoxide dismutase into targeted cells, thereby downregulating the intracellular ROS level. Additionally, the polymer effectively inhibits the fibrillization of three proteins involved in fibrosis, β-lactoglobulin (BLG), insulin, and Aβ1-40, at nanomolar concentrations. Cell culture models demonstrated that DHQ reduces ROS levels induced by Aβ1-40 aggregation, rescuing cell viability and preventing apoptosis. Intracellular delivery of SOD further enhanced the ability to maintain the ROS homeostasis. This polymer offers a multifaceted approach to treating diseases associated with amyloidosis.

Blood diagnostic and prognostic biomarkers in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely limited. The principal pathological alterations of the disease include the selective degeneration of motor neurons in the brain, brainstem, and spinal cord, as well as abnormal protein deposition in the cytoplasm of neurons and glial cells. The biological markers under extensive scrutiny are predominantly located in the cerebrospinal fluid, blood, and even urine. Among these biomarkers, neurofilament proteins and glial fibrillary acidic protein most accurately reflect the pathologic changes in the central nervous system, while creatinine and creatine kinase mainly indicate pathological alterations in the peripheral nerves and muscles. Neurofilament light chain levels serve as an indicator of neuronal axonal injury that remain stable throughout disease progression and are a promising diagnostic and prognostic biomarker with high specificity and sensitivity. However, there are challenges in using neurofilament light chain to differentiate amyotrophic lateral sclerosis from other central nervous system diseases with axonal injury. Glial fibrillary acidic protein predominantly reflects the degree of neuronal demyelination and is linked to non-motor symptoms of amyotrophic lateral sclerosis such as cognitive impairment, oxygen saturation, and the glomerular filtration rate. TAR DNA-binding protein 43, a pathological protein associated with amyotrophic lateral sclerosis, is emerging as a promising biomarker, particularly with advancements in exosome-related research. Evidence is currently lacking for the value of creatinine and creatine kinase as diagnostic markers; however, they show potential in predicting disease prognosis. Despite the vigorous progress made in the identification of amyotrophic lateral sclerosis biomarkers in recent years, the quest for definitive diagnostic and prognostic biomarkers remains a formidable challenge. This review summarizes the latest research achievements concerning blood biomarkers in amyotrophic lateral sclerosis that can provide a more direct basis for the differential diagnosis and prognostic assessment of the disease beyond a reliance on clinical manifestations and electromyography findings.

Dopaminergic neurodegeneration in Gerstmann-Sträussler-Scheinker (P102L) disease: insights from imaging and pathological examination.

Gerstmann-Sträussler-Scheinker (GSS) disease is an inherited prion disease characterized by dementia, cerebellar ataxia, and painful sensory disturbances. GSS is pathologically defined by the presence of amyloid plaques comprised of prion protein predominantly localized in the cerebral cortex, cerebellar cortex, and basal ganglia, resulting from mutations in the prion protein gene. This study investigated five cases of GSS P102L [GSS caused by a leucine (L) substitution of proline (P) at position 102 of the prion protein gene] with L-dopa-resistant extrapyramidal symptoms and reduced dopamine transporter single-photon emission computed tomography (DAT-SPECT) uptake. Clinical findings revealed diverse manifestations, with all cases exhibiting parkinsonism, and four patients had a vertical gaze palsy. Notably, all patients showed reduced striatal DAT-SPECT uptake, indicating neurodegeneration of the nigrostriatal system. Autopsy findings in one case confirmed prion protein plaques and dopaminergic neuron loss in the substantia nigra of a patient with GSS P102L. Additionally, reduced DAT immunostaining was observed in the putamen compared with a control. While previous studies have identified reduced DAT-SPECT and positron emission tomography uptake in Creutzfeldt-Jakob disease and fatal familial insomnia owing to nigrostriatal neurodegeneration induced by abnormal prion protein deposition, similar phenomena in GSS P102L have not been reported. This study provides support for a correlation between abnormal prion protein deposition and nigrostriatal system degeneration in GSS P102L. Our results reveal the importance of considering GSS P102L in cases of atypical Parkinsonism and abnormal DAT-SPECT results, which would serve as a valuable indicator for subsequent prion genetic testing.

Challenges in the approach to a patient with aortic stenosis and cardiac amyloidosis with ATTR mutation associated with negative scintigraphy - A case report

Cardiac amyloidosis (CA) poses significant diagnostic and therapeutic challenges. In this case report, we detail a patient with CA due to a rare transthyretin (CA-TTR) mutation, manifesting with negative myocardial scintigraphy and requiring genetic testing for diagnosis. The patient also had severe aortic stenosis (AS), necessitating discussion with a heart team to determine the optimal treatment strategy. A 70-year-old male with a family history of sudden death was previously diagnosed with third-degree atrioventricular block and treated with a pacemaker. He presented with worsening exertional dyspnoea, and examination revealed a third heart sound, a systolic murmur indicative of AS and bilateral muscular atrophy in the thenar region. Transthoracic echocardiography indicated severe AS and moderate left ventricular dysfunction, with images suggesting infiltrative disease. Pyrophosphate scintigraphy revealed no abnormal cardiac tracer uptake. Cardiac magnetic resonance imaging (MRI) revealed extensive, heterogeneous, subendocardial late gadolinium enhancement in both the atria and ventricles, which was consistent with CA. Genetic testing identified the Phe84Leu mutation in the TTR gene. Following heart team discussions, the patient underwent successful transcatheter aortic valve implantation (TAVI) and remained asymptomatic in follow-up, being monitored at an outpatient clinic specializing in CA and using tafamidis. CA-TTR can be an autosomal dominant disease with variable penetrance involving abnormal amyloid protein deposition in tissues and can often be diagnosed noninvasively via myocardial scintigraphy. However, some TTR mutations do not affect scintigraphy results, necessitating genetic testing when clinical suspicion is high, potentially avoiding endomyocardial biopsy. Moreover, AS occurs in up to 16% of TTR amyloidosis patients, with the conditions mutually exacerbating each other. Recent consensus suggests that TAVI reduces mortality in patients with severe AS and amyloidosis. Various diagnostic algorithms emphasize the use of myocardial scintigraphy for suspected CA-TTR. Genetic testing is crucial when scintigraphy results are negative, but clinical suspicion remains high, potentially circumventing invasive procedures. Compared with medical management alone, TAVI has been shown to improve quality of life and survival in patients with concurrent severe AS and CA.

Enhancing Classification of Alzheimer’s Disease using Spatial Attention Mechanism

Aim This study aims to enhance the precision of Alzheimer's disease (AD) detection by integrating Spatial Attention Mechanism into a Convolutional Neural Network (CNN) architecture. Background Alzheimer's disease is a progressive neurodegenerative disorder characterized by abnormal protein deposits in the brain, leading to nerve cell loss and posing a significant global health challenge. Early and accurate detection is crucial for disease management and treatment due to the lack of a cure and the disease's severe progression. Objective The objective of this research is to improve the accuracy of Alzheimer's disease classification using MRI data by implementing a Spatial Attention Mechanism in a CNN architecture. Methods The study utilized T1-weighted MRI data from the OASIS 1 and OASIS 2 datasets. The key innovation is the Spatial Attention layer incorporated within a CNN model, which computes the average of each channel in the input feature map. This layer guides subsequent layers to focus on critical brain regions, enhancing the model's accuracy in differentiating between Alzheimer's disease stages. Results The model achieved a validation accuracy of 99.69% with a sensitivity and specificity of 1.0000, demonstrating its reliability in distinguishing between different stages of Alzheimer's disease. The adaptability of the Spatial Attention layer allows the model to assign higher weights to crucial brain regions, improving its discriminative power. Conclusion The integration of the Spatial Attention Mechanism into the CNN architecture significantly contributes to the early detection of Alzheimer's disease, enabling timely interventions. This innovative approach has the potential to revolutionize Alzheimer's diagnosis by enhancing accuracy and offering a robust solution for classification.

A Case Report on Renal Amyloidosis

Amyloidosis involves the deposition of abnormal proteins in various tissue and result in progressive organ dysfunction, commonly affecting multiple organs. Two types of systemic amyloidosis are AA and AL, the former is associated with acute phase reaction and the later is composed of light chain immunoglobulin. This disease commonly affects the kidneys and is evidenced by massive proteinuria. A biopsy is the gold standard of diagnosis, with Congo Red staining revealing an apple green birefringence under polarized light microscope. We are presenting a 45 years old male who presented with rapid rising serum creatinine with history of multiple myeloma (non secretory). There was also history of spine tuberculosis.

Inhibition of tartrate-resistant acid phosphatase 5 can prevent cardiac fibrosis after myocardial infarction

BackgroundMyocardial infarction (MI) leads to enhanced activity of cardiac fibroblasts (CFs) and abnormal deposition of extracellular matrix proteins, resulting in cardiac fibrosis. Tartrate-resistant acid phosphatase 5 (ACP5) has been shown to promote cell proliferation and phenotypic transition. However, it remains unclear whether ACP5 is involved in the development of cardiac fibrosis after MI. The present study aimed to investigate the role of ACP5 in post-MI fibrosis and its potential underlying mechanisms.MethodsClinical blood samples were collected to detect ACP5 concentration. Myocardial fibrosis was induced by ligation of the left anterior descending coronary artery. The ACP5 inhibitor, AubipyOMe, was administered by intraperitoneal injection. Cardiac function and morphological changes were observed on Day 28 after injury. Cardiac CFs from neonatal mice were extracted to elucidate the underlying mechanism in vitro. The expression of ACP5 was silenced by small interfering RNA (siRNA) and overexpressed by adeno-associated viruses to evaluate its effect on CF activation.ResultsThe expression of ACP5 was increased in patients with MI, mice with MI, and mice with Ang II-induced fibrosis in vitro. AubipyOMe inhibited cardiac fibrosis and improved cardiac function in mice after MI. ACP5 inhibition reduced cell proliferation, migration, and phenotypic changes in CFs in vitro, while adenovirus-mediated ACP5 overexpression had the opposite effect. Mechanistically, the classical profibrotic pathway of glycogen synthase kinase-3β (GSK3β)/β-catenin was changed with ACP5 modulation, which indicated that ACP5 had a positive regulatory effect. Furthermore, the inhibitory effect of ACP5 deficiency on the GSK3β/β-catenin pathway was counteracted by an ERK activator, which indicated that ACP5 regulated GSK3β activity through ERK-mediated phosphorylation, thereby affecting β-catenin degradation.ConclusionACP5 may influence the proliferation, migration, and phenotypic transition of CFs, leading to the development of myocardial fibrosis after MI through modulating the ERK/GSK3β/β-catenin signaling pathway.

Stable ubiquitin conjugation for biological interrogation of ubiquitinated tau repeat domain

Protein semisynthesis approaches are key for gaining insights into the effects of post-translational modifications (PTMs) on the structure and function of modified proteins. Among PTMs, ubiquitination involves the conjugation of a small protein modifier to a substrate amino acid residue and is unique in controlling a variety of cellular processes. Interest has grown in understanding the role of ubiquitination in neurodegenerative conditions, including tauopathies. The latter are characterized by the accumulation of the intrinsically disordered protein tau in the form of neurofibrillary tangles in the brains of patients. The presence of ubiquitinated tau in the pathological aggregates suggests that ubiquitination might play a role in the formation of abnormal protein deposits. In this study, we developed a new strategy, based on dehydroalanine chemistry, to install wild type ubiquitin on a tau repeat domain construct with site-specificity. We optimized a three-step reaction which yielded a good amount of highly pure tau repeat domain ubiquitinated in position 353. The structural features of the conjugate were examined by circular dichroism and NMR spectroscopy. The ubiquitinated tau was challenged in a number of assays: fibrils formation under aggregating conditions in vitro, chemical stability upon exposure to a variety of biological media including cell extracts, and internalization into astrocytes. The results demonstrated the wide applicability of the new semisynthetic strategy for the investigation of ubiquitinated substrates in vitro or in cell, and in particular for studying if ubiquitination has a role in the molecular mechanisms that underlie the aberrant transition of tau into pathological aggregates.

Anticoagulation in Atrial Fibrillation Associated With Cardiac Amyloidosis: A Narrative Review.

Cardiac amyloidosis (CA) involves the abnormal deposition and accumulation of amyloid proteins in the heart muscle. A hallmark of disease progression is declining heart function, which can lead to structural irregularities, arrhythmias, and ultimately heart failure. Atrial fibrillation (AF) is the most common arrhythmia that presents in CA patients, and this arrhythmia is significant because it can moderately increase the risk of patients developing intracardiac thrombi, thereby putting them at risk for thromboembolic events. The management of this complication entails the use of anticoagulants like vitamin K antagonists and direct oral anticoagulants to reduce the risk of thrombus formation. This article seeks to review AF in CA and the use of anticoagulation therapy for the management and reduction of thromboembolic risk. The major conclusions of this review are centered around the need for safe administration of anticoagulant therapy to CA patients, regardless of their CHA2DS2-VASc risk score. This review highlights the importance of taking a multidisciplinary or collaborative approach to CA treatment to ensure that all aspects of this multifaceted disease can be properly managed while minimizing adverse events like bleeding risk and drug-drug interactions.

A Rare Case of Cardiac Amyloidosis Secondary to Multiple Myeloma in A Young Male Presenting with Shortness of Breath

Introduction: Multiple myeloma (MM) is a haematological malignancy associated with various systemic manifestations, including AL amyloidosis.AL amyloidosis is a systemic condition arising from abnormal protein misfolding and deposition, leading to organ dysfunction. Cardiorenal involvement is characteristic. Cardiac amyloidosis causes significant morbidity and mortality, particularly in MM patients. Case Report: A 40-year-old previously well male presented with exertional dyspnoea, lower limb swelling, and frothy urine. Clinical examination and investigations were consistent with an MM complicated by AL amyloidosis affecting the heart and kidneys. The diagnosis of amyloidosis was confirmed through renal biopsies revealing Congo red positivity, along with cardiac imaging showing typical amyloidosis findings. The presence of bone marrow plasma cells 72% confirmed myeloma. Conclusion: This case highlights the challenges in managing MM-associated AL amyloidosis with cardiac and renal involvement. It underscores the importance of comprehensive diagnostic approaches, multidisciplinary collaboration, and tailored treatment strategies. Despite the poor prognosis, diligent management can lead to favourable outcomes and improved quality of life for affected individuals.

Management of Arrhythmias and Conduction Disorders in Amyloid Cardiomyopathy.

Cardiac amyloidosis, a condition characterized by abnormal protein deposition in the heart, leads to restrictive cardiomyopathy and is notably associated with an increased risk of arrhythmias and conduction disorders. This article reviews the current understanding and management strategies for these cardiac complications, with a focus on recent advancements and clinical challenges. The prevalence and impact of atrial arrhythmias, particularly atrial fibrillation, are examined, along with considerations for stroke risk and anticoagulation therapy. The article also addresses the complexities of managing rate and rhythm control, outlining the utility and limitations of pharmacological agents and interventions such as catheter ablation. Furthermore, it reviews the challenges in the treatment of ventricular arrhythmias, including the contentious use of implantable cardioverter-defibrillators for primary and secondary prevention. Individualized approaches, considering the unique characteristics of cardiac amyloidosis, are paramount. Continuous research and clinical exploration are essential to refine treatment strategies and improve outcomes in this challenging patient population.

Misfolded protein deposits in Parkinson’s disease and Parkinson’s disease-related cognitive impairment, a [11C]PBB3 study

Parkinson’s disease (PD) is associated with aggregation of misfolded α-synuclein and other proteins, including tau. We designed a cross-sectional study to quantify the brain binding of [11C]PBB3 (a ligand known to bind to misfolded tau and possibly α-synuclein) as a proxy of misfolded protein aggregation in Parkinson’s disease (PD) subjects with and without cognitive impairment and healthy controls (HC). In this cross-sectional study, nineteen cognitively normal PD subjects (CN-PD), thirteen cognitively impaired PD subjects (CI-PD) and ten HC underwent [11C]PBB3 PET. A subset of the PD subjects also underwent PET imaging with [11C](+)DTBZ to assess dopaminergic denervation and [11C]PBR28 to assess neuroinflammation. Compared to HC, PD subjects showed higher [11C]PBB3 binding in the posterior putamen but not the substantia nigra. There was no relationship across subjects between [11C]PBB3 and [11C]PBR28 binding in nigrostriatal regions. [11C]PBB3 binding was increased in the anterior cingulate in CI-PD compared to CN-PD and HC, and there was an inverse correlation between cognitive scores and [11C]PBB3 binding in this region across all PD subjects. Our results support a primary role of abnormal protein deposition localized to the posterior putamen in PD. This suggests that striatal axonal terminals are preferentially involved in the pathophysiology of PD. Furthermore, our findings suggest that anterior cingulate pathology might represent a significant in vivo marker of cognitive impairment in PD, in agreement with previous neuropathological studies.

Sleep disturbance in clinical and preclinical scrapie-infected sheep measured by polysomnography

Neurodegenerative diseases are characterised by neuronal loss and abnormal deposition of pathological proteins in the nervous system. Among the most common neurodegenerative diseases are Alzheimer’s disease (AD), Parkinson’s disease (PD), Huntington’s disease and transmissible spongiform encephalopathies (TSEs). Sleep and circadian rhythm disturbances are one of the most common symptoms in patients with neurodegenerative diseases. Currently, one of the main objectives in the study of TSEs is to try to establish an early diagnosis, as clinical signs do not appear until the damage to the central nervous system is very advanced, which prevents any therapeutic approach. In this paper, we provide the first description of sleep disturbance caused by classical scrapie in clinical and preclinical sheep using polysomnography compared to healthy controls. Fifteen sheep classified into three groups, clinical, preclinical and negative control, were analysed. The results show a decrease in total sleep time as the disease progresses, with significant changes between control, clinical and pre-clinical animals. The results also show an increase in sleep fragmentation in clinical animals compared to preclinical and control animals. In addition, sheep with clinical scrapie show a total loss of Rapid Eye Movement sleep (REM) and alterations in Non Rapid Eyes Movement sleep (NREM) compared to control sheep, demonstrating more shallow sleep. Although further research is needed, these results suggest that prion diseases also produce sleep disturbances in animals and that polysomnography could be a diagnostic tool of interest in clinical and preclinical cases of prion diseases.

The role of the Pin1-cis P-tau axis in the development and treatment of vascular contribution to cognitive impairment and dementia and preeclampsia.

Tauopathies are neurodegenerative diseases characterized by deposits of abnormal Tau protein in the brain. Conventional tauopathies are often defined by a limited number of Tau epitopes, notably neurofibrillary tangles, but emerging evidence suggests structural heterogeneity among tauopathies. The prolyl isomerase Pin1 isomerizes cis P-tau to inhibit the development of oligomers, tangles and neurodegeneration in multiple neurodegenerative diseases such as Alzheimer's disease, traumatic brain injury, vascular contribution to cognitive impairment and dementia (VCID) and preeclampsia (PE). Thus, cis P-tau has emerged as an early etiological driver, blood marker and therapeutic target for multiple neurodegenerative diseases, with clinical trials ongoing. The discovery of cis P-tau and other tau pathologies in VCID and PE calls attention for simplistic classification of tauopathy in neurodegenerative diseases. These recent advances have revealed the exciting novel role of the Pin1-cis P-tau axis in the development and treatment of vascular contribution to cognitive impairment and dementia and preeclampsia.