Carpal Tunnel Syndrome: A Marker for Amyloidosis

Introduction: Amyloidosis are systemic conditions and carpal tunnel syndrome (CTS) precedes the principal systemic complications and can be used as an early marker. Our objective was to determine the frequency of amyloid deposition in idiopathic CTS and its systemic impact. Methods: We retrospectively evaluated patients with CTS between September 2019 to January 2020. Samples from the anterior carpal ligament were pathologically evaluated and amyloid deposition was confirmed by apple-green birefringence on polarized light using Congo red stain. When amyloid was detected we performed genetic testing for transthyretin variants (ATTRv), immunofixation electrophoresis in serum and urine for light chains and multidisciplinary evaluation. Results: Thirty consecutive patients were included, 19 women, 11 men, mean age 70 years old (range 42 - 89 years). We identified 3 patients (10%) with amyloid deposits (mean age: 78.6 years, 2 men, 1 woman). Genetic testing for ATTRv and light chains studies were negative. During follow-up: The first patient required aortic valve replacement. The second patient developed progressive cardiac failure with syncopal episodes, atrioventricular block and atrial fibrillation and required a pacemaker and anticoagulation. The third patient had unexplained chronic edemas. The cardiac evaluation in all 3 patients revealed left ventricular hypertrophy and myocardial uptake (Perugini Score > 2) in their nuclear bone scintigraphies with technetium pyrophosphate. Two patients were treated with tafamidis and one patient died due to refractory cardiac insufficiency. Discussion: Our findings underline the importance of investigating amyloidosis in idiopathic CTS. The identification of deposits allows early diagnosis of cardiac amyloidosis leading to timely intervention and treatment.

Medin synergized with vascular amyloid-beta deposits accelerates cognitive decline in Alzheimer's disease:a potential biomarker

Brain vascular dysfunction in Alzheimer s disease(AD) pathogenesis has become increasingly clea r.Accumulating evidence shows that damaged vascular,including large or small vessels and even neurovascular unit,may accelerate the neuropathological process of AD via disrupting brain hypoperfusion,aberrant angiogenesis,and neuroinflammatory response,etc.Thus,vascular dysfunction makes a substantially contribution to the cognitive decline of AD patients.

Current perspective on amyloid aggregation accelerating properties of the artificial butter flavoring,diacetyl

The amyloid—what peptide can resist its entropic bliss?Without kinetic barricades and chaperones,most peptides would simply tumble down that precipice.The amyloid-β(Aβ) peptides are understood to underlie the hallmark pathology of Alzheimer's disease(AD) and are considered one of the causative factors for neurodegeneration and cognitive impairment.AD affects critical connected structures within the brain that are responsible for memory,language,and social behavior.

Transmission of amyloid-βpathology in humans:a perspective on clinical evidence

Transmission of misfolded amyloid-β(Aβ)aggregates between human subjects:Protein misfolding disorders are a family of diseases characterized by the accumulation of misfolded protein aggregates.These proteinaceous structures,also known as amyloids,are key drivers of fatal neurodegenerative disorders such as prion diseases,Alzheimer’s disease(AD),Parkinson’s disease,and others.

Smart electrochemical sensing of amyloid-beta to manage total Alzheimer's diseases

Need for Alzheimer's disease progression monitoring:Alzheimer's disease(AD)is an irreversible progressive brain disorder that causes severe and incurable neuro-impairment.The World Health Organization estimates that 55 million people are affected by AD dementia by 2020 which may exceed 78 million by 2030 and 139 in 2050.The estimated cost to manage AD is above US$1.3 trillion,which will further increase to US$2.8 trillion by 2030.

Role of peripheral amyloid-β aggregates in Alzheimer’s disease: mechanistic, diagnostic, and therapeutic implications

Compelling evidence demonstrates that the levels of peripheral amyloid-β(Aβ)fluctuate in Alzheimer’s disease(AD)patients.Moreover,Aβdeposits have been identified in peripheral tissues.However,the relevance of peripheral Aβ(misfolded or not)in pathological situations,and the temporal appearance of these pathological fluctuations,are not well understood.The presence of misfolded Aβin peripheral compartments raises concerns on potential inter-individual transmissions considering the well-reported prion-like properties of this disease-associated protein.The latter is supported by multiple reports demonstrating that Aβmisfolding can be transmitted between humans and experimental animals through multiple routes of exposure.In this mini-review,we discuss the potential implications of peripheral,disease-associated Aβin disease mechanisms,as well as in diagnostic and therapeutic approaches.

Design and redesign journey of a drug for transthyretin amyloidosis

The misfolding and subsequent aggregation of proteins into amyloid fibrils underlie the onset of a variety of human disorders collectively known as amyloidosis.Transthyretin(TTR)is one of the>30 amyloidogenic proteins identified to date and is associated with a group of highly debilitating and life-threatening disorders called TTR amyloidosis(ATTR).ATTR comprises senile systemic amyloidosis,which is linked to wild-type(WT)TTR aggregation,and hereditary ATTR,a dominantly inherited disorder caused by the deposition of one of over 130 TTR genetic variants.Senile systemic amyloidosis is a prevalent age-related amyloidosis,affecting up to 25%of the population over 80 years of age,and is characterized by the build-up of TTR fibrils in the myocardium.Regarding hereditary ATTR,the clinical presentation is highly heterogeneous,primarily affecting the peripheral nervous system(familial amyloid polyneuropathy-FAP)or the heart(familial amyloid cardiomyopathy).In rare cases,aggregation develops in the central nervous system,giving rise to a phenotype known as familial leptomeningeal amyloidosis(Carroll et al.,2022).

Corrigendum: Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease

In the article titled“Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease”published on pages 2467-2479,Issue 11,Volume 19 of Neural Regeneration Research(Tang et al.,2024),there are some errors in selecting the appropriate images in Figure 7 by authors during assembling the images.

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

Although many causes of Alzheimer’s disease(AD)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the pathology.However,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in AD,being able to precede and influence one another.Some researchers argue that these proteins are mere executors rather than primary causes of pathology.Therefore,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early AD.Moreover,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

Management of cerebral amyloid angiopathy and atrial fibrillation:We are still far from precision medicine

The use of anticoagulation therapy could prove to be controversial when trying to balance ischemic stroke and intracranial bleeding risks in patients with concurrent cerebral amyloid angiopathy(CAA)and atrial fibrillation(AF).In fact,CAA is an age-related cerebral vasculopathy that predisposes patients to intracerebral hemorrhage.Nevertheless,many AF patients require oral systemic dose-adjusted warfarin,direct oral anticoagulants(such as factor Xa inhibitors)or direct thrombin inhibitors to control often associated with cardioembolic stroke risk.The prevalence of both CAA and AF is expected to rise,due to the aging of the population.This clinical dilemma is becoming increasingly common.In patients with coexisting AF and CAA,the risks/benefits profile of anticoagulant therapy must be assessed for each patient individually due to the lack of a clear-cut consensus with regard to its risks in scientific literature.This review aims to provide an overview of the management of patients with concomitant AF and CAA and proposes the implementation of a risk-based decision-making algorithm.

Recurrent Transient Ischemic Attacks Revealing Cerebral Amyloid Angiopathy: A Comprehensive Case

This case report investigates the manifestation of cerebral amyloid angiopathy (CAA) through recurrent Transient Ischemic Attacks (TIAs) in an 82-year-old patient. Despite initial diagnostic complexities, cerebral angiography-MRI revealed features indicative of CAA. Symptomatic treatment resulted in improvement, but the patient later developed a fatal hematoma. The discussion navigates the intricate therapeutic landscape of repetitive TIAs in the elderly with cardiovascular risk factors, emphasizing the pivotal role of cerebral MRI and meticulous bleeding risk management. The conclusion stresses the importance of incorporating SWI sequences, specifically when suspecting a cardioembolic TIA, as a diagnostic measure to explore and exclude CAA in the differential diagnosis. This case report provides valuable insights into these challenges, highlighting the need to consider CAA in relevant cases.

Diagnostic significance of serum levels of serum amyloid A,procalcitonin,and high-mobility group box 1 in identifying necrotising enterocolitis in newborns

BACKGROUND Necrotising enterocolitis(NEC)is a critical gastrointestinal emergency affecting premature and low-birth-weight neonates.Serum amyloid A(SAA),procalcitonin(PCT),and high-mobility group box 1(HMGB1)have emerged as potential biomarkers for NEC due to their roles in inflammatory response,tissue damage,and immune regulation.AIM To evaluate the diagnostic value of SAA,PCT,and HMGB1 in the context of NEC in newborns.METHODS The study retrospectively analysed the clinical data of 48 newborns diagnosed with NEC and 50 healthy newborns admitted to the hospital.Clinical,radiological,and laboratory findings,including serum SAA,PCT,and HMGB1 Levels,were collected,and specific detection methods were used.The diagnostic value of the biomarkers was evaluated through statistical analysis,which was performed using chi-square test,t-test,correlation analysis,and receiver operating characteristic(ROC)analysis.RESULTS The study demonstrated significantly elevated levels of serum SAA,PCT,and HMGB1 Levels in newborns diagnosed with NEC compared with healthy controls.The correlation analysis indicated strong positive correlations among serum SAA,PCT,and HMGB1 Levels and the presence of NEC.ROC analysis revealed promising sensitivity and specificity for serum SAA,PCT,and HMGB1 Levels as potential diagnostic markers.The combined model of the three biomarkers demonstrating an extremely high area under the curve(0.908).CONCLUSION The diagnostic value of serum SAA,PCT,and HMGB1 Levels in NEC was highlighted.These biomarkers potentially improve the early detection,risk stratification,and clinical management of critical conditions.The findings suggest that these biomarkers may aid in timely intervention and the enhancement of outcomes for neonates affected by NEC.

Primary imaging features and recent application of PET tracers in cerebral amyloid angiopathy

Cerebral amyloid angiopathy(CAA)is a small vessel disease of the brain characterized by the progressive deposition of amyloid-β(Aβ)plaques in the walls of cerebral blood vessels.It presents with a subtle course and sudden onset,and currently,there are no specific therapeutic interventions available.Accurate diagnosis of CAA could enable targeted interventions in the early stages of the disease,potentially mitigating the disease’s effects.Herein,we review the primary imaging biomarkers used in the diagnosis of CAA,including their mechanisms,imaging characteristics,and significance.We also provide an interpretation of the latest version(v2.0)of the Boston criteria,which are commonly used in the clinical diagnosis of CAA.Additionally,this study introduces various positron emission tomography(PET)tracers for CAA and reviews their application values in the diagnosis of CAA.

Dysfunction of blood-brain barrier in cerebral amyloid angiopathy

Increasing evidence demonstrated that the blood-brain barrier(BBB)was involved in developing cerebral amyloid angiopathy(CAA).The BBB participates in the neurovascular coupling and regulates the transport of substances,which is closely related to neurodegenerative diseases.In CAA,the deposition of amyloid beta(Aβ)in arteries,capillaries,and arterioles of meninges and cerebral cortex results in the destruction of the BBB,chronic inflammatory response,chronic cerebral hypoperfusion,and dysfunction of the neurovascular unit,which eventually leads to neurodegeneration.At the same time,CAA is an age-related disease.Patients with CAA often have some risk factors for cerebrovascular diseases,such as hypertension and diabetes,which can further aggravate the damage to the BBB.Thus,it is of great significance to pay attention to the BBB in the pathogenesis and future intervention targets of CAA.Therefore,this manuscript reviewed the dysfunction of the BBB in CAA.

The expanding amyloid family:Structure,stability,function,and pathogenesis

The hidden world of amyloid biology has suddenly snapped into atomic-level focus,revealing over 80 amyloid protein fibrils,both pathogenic and functional.Unlike globular proteins,amyloid proteins flatten and stack into unbranched fibrils.Stranger still,a single protein sequence can adopt wildly different two-dimensional conformations,yielding distinct fibril polymorphs.

A pancreatic player in dementia:pathological role for islet amyloid polypeptide accumulation in the brain

Type 2 diabetes mellitus patients have a markedly higher risk of developing dementia.While multiple factors contribute to this predisposition,one of these involves the increased secretion of amylin,or islet amyloid polypeptide,that accompanies the pathophysiology of type 2 diabetes mellitus.Islet amyloid polypeptide accumulation has undoubtedly been implicated in various forms of dementia,including Alzheimer’s disease and vascular dementia,but the exact mechanisms underlying islet amyloid polypeptide’s causative role in dementia are unclear.In this review,we have summarized the literature supporting the various mechanisms by which islet amyloid polypeptide accumulation may cause neuronal damage,ultimately leading to the clinical symptoms of dementia.We discuss the evidence for islet amyloid polypeptide deposition in the brain,islet amyloid polypeptide interaction with other amyloids implicated in neurodegeneration,neuroinflammation caused by islet amyloid polypeptide deposition,vascular damage induced by islet amyloid polypeptide accumulation,and islet amyloid polypeptide-induced cytotoxicity.There are very few therapies approved for the treatment of dementia,and of these,clinical responses have been controversial at best.Therefore,investigating new,targetable pathways is vital for identifying novel therapeutic strategies for treating dementia.As such,we conclude this review by discussing islet amyloid polypeptide accumulation as a potential therapeutic target not only in treating type 2 diabetes mellitus but as a future target in treating or even preventing dementia associated with type 2 diabetes mellitus.

Cannabidiol-Mediated Sequestration of Alzheimer’s Amyloid-β Peptides in ADDL Oligomers

Cannabidiol (CBD), one of the most studied phytocannabinoids, is non-psychotropic and can induce protective effects on the central nervous system against acute and chronic brain injury. Interestingly, CBD inhibits processes relating to amyloid beta (Aβ)-induced neurotoxicity in mouse models of Alzheimer’s disease, though the detailed molecular mechanism underlying the CBD neurotoxicity modulation is not fully understood. In this study, using atomic force microscopy, we find that CBD promotes the aggregation of Aβ peptides, enhancing the formation of Aβ oligomers, also known as Aβ-derived diffusible ligands (ADDLs). The CBD-mediated sequestration of Aβ monomers in soluble ADDLs could reduce neurotoxicity. This study highlights a possible role of CBD in modulating the formation of ADDL aggregates and provides insight into potentially neuroprotective properties of CBD in Alzheimer’s disease.

Clinical features of retinal amyloid angiopathy with transthyretin Gly83Arg variant

AIM:To report on the clinical features of patients with retinal amyloid angiopathy(RAA)who were identified to be caused by the transthyretin(TTR)Gly83Arg variant.METHODS:Case series of five patients diagnosed with RAA was collected at Affiliated Hospital of Zunyi Medical University from January 2010 to December 2021.The clinical features,therapeutic strategies,and prognoses of all patients were reviewed.RESULTS:Five patients with a mean age of 52.00±7.23y were diagnosed as RAA.These patients were previously diagnosed with hereditary transthyretin amyloidosis caused by the TTR Gly83Arg variant.Vitreous opacity was found in all 10 eyes,and 7 eyes developed RAA 2 to 20y after the onset of hereditary transthyretin amyloidosis.The clinical manifestations were recurrent vitreous hemorrhage in 2 eyes(29%),neovascular glaucoma in 2 eyes(29%),and iris neovascularization in 1 eye(14%).Microangioma lesions were found in all affected eyes that underwent fundus fluorescein angiography(FFA)in this group of cases,and the incidence of the retinal non-perfusion area was 67%.Although no cases of retinal neovascularization were found,the prognosis of visual acuity was not ideal.CONCLUSION:This is the first report of RAA in patients with the TTR Gly83Arg variant.Complications such as RAA and glaucoma will seriously affect the visual prognosis of patients.Thereafter,regular ophthalmic follow-up of patients with hereditary transthyretin amyloidosis is essential.And FFA after vitrectomy is very important,which can help ophthalmologists detect RAA earlier and treat it in time.

Impaired autophagy in amyloid-beta pathology:A traditional review of recent Alzheimer's research

Alzheimer’s disease(AD) is the most prevalent neurodegenerative disorder. The major pathological changes in AD progression are the generation and accumulation of amyloid-beta(Aβ) peptides as well as the presence of abnormally hyperphosphorylated tau proteins in the brain. Autophagy is a conserved degradation pathway that eliminates abnormal protein aggregates and damaged organelles. Previous studies have suggested that autophagy plays a key role in the production and clearance of Aβ peptides to maintain a steady-state of Aβ peptides levels.However, a growing body of evidence suggests that autophagy is significantly impaired in the pathogenesis of AD, especially in Aβ metabolism. Therefore, this article reviews the latest studies concerning the mechanisms of autophagy, the metabolism of Aβ peptides, and the defective autophagy in the production and clearance of Aβpeptides. Here, we also summarize the established and new strategies for targeting autophagy in vivo and through clinical AD trials to identify gaps in our knowledge and to generate further questions.

Regional differences in islet amyloid deposition in the residual pancreas with new-onset diabetes secondary to pancreatic ductal adenocarcinoma

BACKGROUND Islet amyloid deposition and reducedβ-cell mass are pathological hallmarks in type 2 diabetes mellitus subjects.To date,the pathological features of the islets in diabetes secondary to pancreatic ductal adenocarcinoma(PDAC)have not been specifically addressed.AIM To provide further insight into the relationship between islet amyloid deposition of the residual pancreas in PDAC patients and to explore whether regional differences(proximal vs distal residual pancreas)are associated with islet amyloid deposition.METHODS We retrospectively collected clinical information and pancreatic tissue removed from tumors of 45 PDAC patients,including 14 patients with normal glucose tolerance(NGT),16 patients with prediabetes and 15 new-onset diabetes(NOD)patients diagnosed before surgery by an oral glucose tolerance test at West China Hospital from July 2017 to June 2020.Pancreatic volume was calculated by multiplying the estimated area of pancreatic tissue on each image slice by the interval between slices based on abdominal computer tomography scans.Several sections of paraffin-embedded pancreas specimens from both the proximal and/or distal regions remote from the tumor were stained as follows:(1)Hematoxylin and eosin for general histological appearance;(2)hematoxylin and insulin for the determination of fractionalβ-cell area(immunohistochemistry);and(3)quadruple insulin,glucagon,thioflavin T and DAPI staining for the determination ofβ-cell area,α-cell area and amyloid deposits.RESULTS Screening for pancreatic histologic features revealed that duct obstruction with islet amyloid deposition,fibrosis and marked acinar atrophy were robust in the distal pancreatic regions but much less robust in the proximal regions,especially in the prediabetes and NOD groups.Consistent with this finding,the remnant pancreatic volume was markedly decreased in the NOD group by nearly one-half compared with that in the NGT group(37.35±12.16 cm^(3) vs 69.79±18.17 cm^(3),P<0.001).As expected,islets that stained positive for amyloid(islet amyloid density)were found in the majority of PDAC cases.The proportion of amyloid/islet area(severity of amyloid deposition)was significantly higher in both prediabetes and NOD patients than in NGT patients(P=0.002;P<0.0001,respectively).We further examined the regional differences in islet amyloid deposits.Islet amyloid deposit density was robustly increased by approximately 8-fold in the distal regions compared with that in the proximal regions in the prediabetes and NOD groups(3.98%±3.39%vs 0.50%±0.72%,P=0.01;12.03%vs 1.51%,P=0.001,respectively).CONCLUSION In conclusion,these findings suggest that robust alterations of the distal pancreas due to tumors can disturb islet function and structure with islet amyloid formation,which may be associated with the pathogenesis of NOD secondary to PDAC.