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.

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.

Cerebral proliferative angiopathy in pediatric age presenting as neurological disorders:A case report

BACKGROUND Cerebral proliferative angiopathy(CPA)is a rare subtype of arteriovenous malformation.It is extremely rare in pediatric patients and has serious implications for developing children.However,reports of these disorders worldwide are limited,and no uniform reference for diagnosis and treatment options exists.We report the case of a 6-year-old with CPA having predominantly neurological dysfunction and review the literature on pediatric CPA.CASE SUMMARY We report the case of a pediatric patient with CPA analyzed using digital subtraction angiography(DSA)who presented initially with a neurological disorder as the main manifestation.This case is the basis for further discussion of the clinical presentation,pathogenesis,diagnosis,and treatment of CPA in children.After the cerebral DSA,the patient was treated conservatively with sedation,fluid replacement,and blood anticoagulation.She could not cooperate with the followup magnetic resonance imaging examination because of her young age,and her family declined further treatment because of the surgery’s high risk.She was followed up for 3 months;her symptoms did not worsen.CONCLUSION This report of rare pediatric CPA can inform and advance clinical research on congenital cerebrovascular diseases.

Cerebrospinal Fluid Biomarkers in Dementia Patients with Cerebral Amyloid Angiopathy

Objective To study the changes of biomarkers in cerebrospinal fluid(CSF) in cerebral amyloid angiopathy(CAA) dementia and Alzheimer's disease.Methods Levels of amyloid protein β(Aβ42,Aβ40) and phosphorylated Tau-protein(P-tau) in CSF and ratio of Aβ42/Aβ40 were tested in 5 cases with CAA dementia and 20 cases with Alzheimer's disease collected at Peking Union Medical College Hospital from December 2001 to March 2011.Results The levels of Aβ42,Aβ40,and P-tau in CSF and ratio of Aβ42/Aβ40 were(660.4±265.2) ng/L,(7111.0±1033.4) ng/L,(71.8±51.5) ng/L,and 0.077±0.033,respectively in CAA dementia and(663.6±365.6) ng/L,(5115.0±2931.1) ng/L,(47.7±38.8) ng/L,and 0.192±0.140,respectively in Alzheimer's disease patients.There were no statistically significant differences between CAA dementia and Alzheimer's disease in terms of these CSF biomarkers(all P>0.05).Conclusion Measurements of CSF biomarkers may not be helpful in differential diagnosis of CAA and Alzheimer's disease.

Endovascular Application of Low-Energy Laser in the Treatment of Dyscirculatory Angiopathy of Alzheimer’s Type

Purpose: We propose an analysis of dyscirculatory angiopathy of Alzheimer’s type (DAAT) endovascular treatment method based on transcatheter revascularization and recovery of collateral and microvascular bed of the brain by means of low-energy transluminal laser irradiation as well as its comparison with traditional Alzheimer’s disease (AD) treatment methods. Methods: The research involved 81 patients aged 34 - 79 (average age 67). 46 (46.8%) patients were treated using endovascular method—Test Group. 35 (43.2%) patients were given conventional treatment—Control Group. Patients were subdivided: Group (CDR-0): 9 (11.1%), pre-clinical stage or increased AD risk;Group (CDR-1): 24 (29.6%), mild dementia and cognitive impairment;Group (CDR-2): 31 (38.3%), moderate dementia and persistent cognitive impairment;Group (CDR-3): 17 (21.0%), severe dementia and cognitive impairment. Research plan included CT or MRI with subsequent temporal lobes volume calculation, brain scintigraphy (SG), rheoencephalography (REG), and cerebral MUGA. There were indications and contraindications for treatment in Test Group. In Group CDR-0, endovascular intervention was prophylactic, against the background of increasing memory impairment;in Groups CDR-1, CDR-2, CDR-3, it was conducted in 1 to 12 years period from AD symptoms appear-ance. Conservative treatment with Memantin and Rivastigmine was carried out in Control Group. Results: In Test Group, positive outcome accompanied by prolonged dementia decline, cognitive impairment decrease, and patients’ transition to CDR group of an earlier stage, was obtained in all cases. In Control Group, patients’ temporary stabilization in their own CDR group was achieved. Conclusions: Endovascular treatment of patients with AD different stages can not only reduce DAAT phenomena but can also cause AD regression possibly accompanied by regenerative processes in the cerebral tissue. Conservative treatment only allows stabilizing the patient’s condition for a while.

Hemorrhagic transformation of ischemic cerebral proliferative angiopathy: A case report

BACKGROUND Cerebral proliferative angiopathy(CPA)is a rare vascular disease characterized by the presence of diffuse vascular proliferation,progressive vascular hyperflow and vasodilation of multiple vessels in the normal brain parenchyma.Unlike cerebral arteriovenous malformations,CPA has a mixed appearance between that of lesions with cell proliferation and endothelial proliferation.To date,the pathogenesis of CPA is unclear,in which changes induced by cortical ischemia in the elastic layer of the blood supply artery and smooth muscle cells may be involved.CASE SUMMARY In this article,we retrospectively analyzed a case of hemorrhagic transformation of ischemic CPA diagnosed by digital subtraction angiography and reviewed the related literature for further exploration of its pathogenesis,diagnosis and treatment.CONCLUSION The information in the present case report may facilitate further clinical research on this cerebrovascular disease.

Dyscirculatory Angiopathy of Alzheimer's Type

Purpose: We assess the significance of dyscirculatory angiopathy of Alzheimer’s type (DAAT) in identify- ing the predisposition to the development and diagnosis of Alzheimer’s disease (AD) different stages. Meth- ods: 108 patients took part in the research:1) 49 aged 34-79 suffering from AD or running an increased risk of its development (those not diagnosed with AD but having growing memory disorders without any mani- festations of dementia or specific cognitive impairments, and having 2 or more immediate relatives with AD) - Test Group;2) 59 aged 28-78 suffering from different types of brain lesions accompanied by dementia but not suffering from AD or corresponding to their age norm - Control Group. All the patients underwent MRI, CT with subsequent calculation of the temporal lobes atrophy degree, brain scintigraphy (SG), rheoencepha- lography (REG), and MUGA. Results: Characteristic features of patients with an increased risk of AD as well as at its various stages are: 1) Temporal lobes and hippocampus atrophy ranging from 4% among those with an increased risk of AD to 62% among those at its advanced stages;2) DAAT manifestations: reduction of the capillary bed in the temporal and frontoparietal regions with the development of multiple arterioven- ous shunts of the same localization and correspondent early venous discharge accompanied by venous stasis on the border of the frontal and parietal region;3) DAAT phenomena equally develop both among those with an increased risk of developing AD and those at various AD stages. Similar changes are not observed among Control Group patients with other brain lesions, regardless of the severity of dementia, as well as among practically healthy people of the corresponding age group. Conclusion: Timely identification of the above- mentioned changes can reveal a predisposition to AD development long before its initial manifestations, and it allows differentiating AD from other diseases attended by dementia. In both cases, timely diagnosis allows beginning timely treatment and thus achieving more stable results.

Histopathological Evidence for Irradiation Angiopathy in Head and Neck Cancer

Objective: To evaluate the incidence of cervical angiopathy caused by radiation therapy for head and neck cancer. Methods: Segments of 57 cervical arteries were obtained during surgery for head and neck malignant tumors and divided into two groups (irradiated group and non-irradiated group) based on the treatment prior to vascular resection. In order to evaluate vascular injury after radiation therapy, we examined the degree of medial atrophy, medial fibrosis, smooth muscle cell (SMC) differentiation in the media and intima, intimal hyperplasia and endothelial cell (EC) injury. Sections of arterial segments were stained with hematoxylin-eosin, Elastica van Gieson and Masson’s trichrome, and immunohistochemistry for α-smooth muscle actin (α-SMA), smoothelin, S100A4 and CD31 in the resected vessels was conducted. Results: The median interval between the completion of radiation therapy and vascular resection was nine months. No significant differences were observed between the two groups in terms of medial atrophy, medial fibrosis and intimal hyperplasia. The ratio of the smoothelin-positive area per α-SMA-positive area in the media and the S100A4-positive proportion in the intima, indicating the degree of differentiation of the medial SMC and dedifferentiation of the intimal SMC, respectively, showed no significant differences, despite the tendency toward a lower smoothelin-positive area per α-SMA-positive area in the media of the irradiated arteries. The EC coverage revealed on CD31 immunohistochemistry was significantly decreased, with mural thrombus adhesion, in the irradiated group. Conclusions: The ECs of small arteries are damaged by irradiation. Although we did not confirm the statistical significance of medial SMC dedifferentiation, a decreased expression of smoothelin tended to be observed in the media of the irradiated arteries. Our findings provide histopathological evidence of irradiation angiopathy in head and neck cancer and may help to improve the surgical safety of microvascular anastomosis and determine the treatment strategy for head and neck tumors.

Cerebral amyloid angiopathy vs Alzheimer’s dementia:Diagnostic conundrum

BACKGROUND Diagnosis of a dementia subtype can be complex and often requires comprehensive cognitive assessment and dedicated neuroimaging.Clinicians are prone to cognitive biases when reviewing such images.We present a case of cognitive impairment and demonstrate that initial imaging may have resulted in misleading the diagnosis due to such cognitive biases.CASE SUMMARY A 76-year-old man with no cognitive impairment presented with acute onset word finding difficulty with unremarkable blood tests and neurological examination.Magnetic resonance imaging(MRI)demonstrated multiple foci of periventricular and subcortical microhaemorrhage,consistent with cerebral amyloid angiopathy(CAA).Cognitive assessment of this patient demonstrated marked impairment mainly in verbal fluency and memory.However,processing speed and executive function are most affected in CAA,whereas episodic memory is relatively preserved,unlike in other causes of cognitive impairment,such as Alzheimer’s dementia(AD).This raised the question of an underlying diagnosis of dementia.Repeat MRI with dedicated coronal views demonstrated mesial temporal lobe atrophy which is consistent with AD.CONCLUSION MRI brain can occasionally result in diagnostic overshadowing,and the application of artificial intelligence to medical imaging may overcome such cognitive biases.

Association of antithrombotic therapy with postoperative rebleeding in patients with cerebral amyloid angiopathy

Background Cerebral amyloid angiopathy is a common cause of subcortical hemorrhage in older adults.Although open hematoma removal may be performed for severe subcortical hemorrhage,its safety in patients with cerebral amyloid angiopathy has not been established,and postoperative rebleeding may occur.Therefore,this study aimed to investigate factors associated with postoperative rebleeding.Methods Out of 145 consecutive patients who had undergone craniotomy for surgical removal of subcortical intracerebral hemorrhage between April 2010 and August 2019 at a single institution in Japan,we examined 109 patients with subcortical hemorrhage who met the inclusion criteria.After excluding 30 patients whose tissue samples were unsuitable for the study,the final study cohort comprised 79 patients.Results Of the 79 patients,50(63%)were diagnosed with cerebral amyloid angiopathy(cerebral amyloid angiopathy group)and 29(37%)were not diagnosed with noncerebral amyloid angiopathy(noncerebral amyloid angiopathy group).Postoperative rebleeding occurred in 12 patients(24%)in the cerebral amyloid angiopathy group and in 2 patients(7%)in the noncerebral amyloid angiopathy group.Preoperative prothrombin time-international normalized ratio and intraoperative bleeding volume were significantly associated with postoperative rebleeding in the cerebral amyloid angiopathy group(odds ratio=42.4,95%confidence interval=1.14-1578;p=0.042 and odds ratio=1.005,95%confidence interval=1.001-1.008;p=0.007,respectively).Conclusions Patients with cerebral amyloid angiopathy-related cerebral hemorrhage who are receiving antithrombotic therapy,particularly warfarin therapy,are at a high risk of postoperative rebleeding.Trial registration Registry and Registration Number of the study:19-220,2019/12/23,retrospectively registered.

Multimodal comparison of plasma proteins associated with blood-brain barrier impairment in Alzheimer’s disease

Background:Vascular impairment is one of the major contributors to dementia.We aimed to identify blood biomarkers suggestive of potential impairment of the blood-brain barrier(BBB)in subjects with Alzheimer’s disease(AD).Methods:We used administrative data from the VA Informatics and Computing Infrastructure Resource Center to study both inpatients and outpatients with AD.Plasma samples from healthy control and AD individuals were analyzed using enzyme-linked immunosorbent assay and proteomics approaches to identify differentially expressed proteins.Bioinformatic analysis was applied to explore significantly enriched pathways.Results:In the same cohort of patients with AD,we found twice number of subjects with cerebral amyloid angiopathy in the two-year period after the onset of AD,compared to the number of subjects with cerebral amyloid angiopathy in the two-year period prior to AD onset.Different pathways related to BBB,like cell adhesion,extracellular matrix organization and Wnt signaling,were activated and differentially expressed proteins such as ADAM22,PDGFR-α,DKK-4,Neucrin and RSOP-1 were identified.Moreover,matrix metalloproteinase-9,which is implicated in causing degradation of basal lamina and BBB disruption,was significantly increased in the plasma of AD patients.Conclusions:Alteration of proteins found in AD subjects could provide new insights into biomarkers regulating permeability and BBB integrity.

Cerebral amyloid angiopathy-related inflammation: current status and future implications

Cerebral amyloid angiopathy-related inflammation (CAA-RI) is a rare but increasingly recognized subtype of CAA. CAA-RI consists of two subtypes: inflammatory cerebral amyloid angiopathy and amyloid β (Aβ)-related angiitis. Acute or subacute onset of cognitive decline or behavioral changes is the most common symptom of CAA-RI. Rapid progressive dementia, headache, seizures, or focal neurological deficits, with patchy or confluent hyperintensity on T2 or fluid-attenuated inversion recovery sequences and evidence of strictly lobar microbleeds or cortical superficial siderosis on susceptibility-weighted imaging imply CAA-RI. The gold standard for diagnosis is autopsy or brain biopsy. However, biopsy is invasive;consequently, most clinically diagnosed cases have been based on clinical and radiological data. Other diagnostic indexes include the apolipoprotein E ε4 allele, Aβ and anti-Aβ antibodies in cerebral spinal fluid and amyloid positron emission tomography. Many diseases with similar clinical manifestations should be carefully ruled out. Immunosuppressive therapy is effective both during initial presentation and in relapses. The use of glucocorticoids and immunosuppressants improves prognosis. This article reviews the pathology and pathogenesis, clinical and imaging manifestations, diagnostic criteria, treatment, and prognosis of CAA-RI, and highlights unsolved problems in the existing research.

Severe pathological manifestation of cerebral amyloid angiopathy correlates with poor outcome from cerebral amyloid angiopathy related intracranial hemorrhage

Background Cerebral amyloid angiopathy （CAA） is one of the main causes of spontaneous intracranial hemorrhage （ICH）. No established link is available between pathological scores of CAA and its outcome. This study aimed to identify the correlations between pathological severity and poor postoperative outcome in the Chinese population. Methods Between May 2006 and April 2011, 367 consecutive patients who underwent surgery for CAA-related ICH in 71 hospitals throughout the mainland of China were enrolled in this study. Twelve months after surgery, we evaluated these patients＇ outcomes according to the modified Rankin Scale （mRS） and statistically correlated risk factors （demographics, medical history, pathological results, and surgical details） that are associated with a favorable （mRS 〈3） and poor （mRS 〉3） outcome groups. Results Risk factors for poor postoperative outcome in 367 patients with CAA-related ICH included advanced age （OR 1.034, 95% CI 1.001-1.067, P=0.042）, CAA pathology severity （OR 2.074, 95% CI 7.140-16.25, P 〈0.001）, lobar hematoma （OR 0.225, 95% CI 0.104-0.486, P 〈0.001）, presence of intraventricular hemorrhage （OR 0.478, 95% CI 0.229-1.001, P=0.050）, and/or subarachnoid hemorrhage （OR 2.629, 95% CI, 1.051-6,577, P=0.039）. Conclusions Poor postoperative outcome of patients with CAA-related ICH was more related to the severe pathological manifestation instead of other factors. Prior ischemia may present an early stage of CAA.

Arterioles in cerebral amyloid angiopathy and vascular dementia

Background Small cerebrovascular lesions are one of the most important factors in cerebral amyloid angiopathy （CAA） and vascular dementia （VaD）. We analyzed the difference of arteriolar pathology between CAA patients （CAAs） and vascular dementia patients without CAA （VaDs）. Methods Ten deceased CAAs and twelve deceased VaDs were available for this study. Five deceased patients without known cerebrovascular diseases served as controls. These patients were all autopsy cases. All transversely cut arterioles in the gray matter and white matter with an external diameter equal to or larger than 30 um and with a maximum of 300 um were examined. The internal and external diameters of arterioles were measured. Results The external diameter of gray matter arterioles in the CAAs was significantly greater than in controls. In gray matter arterioles, the diameter of the lumen in VaDs was markedly smaller than in the CAAs, whereas there was no significant difference between CAAs and controls. CAAs and VaDs may cause remarkable thickening of the arteriolar walls in either white matter or gray matter. The sclerotic index of arterioles in VaDs was significantly greater than in CAAs and controls. Conclusions Stenosis of arterioles occurred in both CAA and VaD, but the tendency was greater in VaD. Arterioles of CAA were also expanded in gray matter, which may be related to lobar hemorrhage. The loss and/or degeneration of vascular smooth muscle cells was predominant in CAA, while the over-proliferation of vascular smooth muscle cells was areater in VaD.

Cerebral amyloid angiopathy with dementia: clinicopathological studies of 17 cases

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The role of amyloid beta clearance in cerebral amyloid angiopathy:more potential therapeutic targets

Cerebral amyloid angiopathy(CAA)is characterized by the deposition of amyloid β-protein(Aβ)in the leptomeningeal and cortical blood vessels,which is an age-dependent risk factor for intracerebral hemorrhage(ICH),ischemic stroke and contributes to cerebrovascular dysfunction leading to cognitive impairment.However clinical prevention and treatment of the disease is very difficult because of its occult onset and severity of the symptoms.In recent years,many anti-amyloid β immunotherapies have not demonstrated clinical efficacy in subjects with Alzheimer’s disease(AD),and the failure may be due to the deposition of Aβ in the cerebrovascular export pathway resulting in further damage to blood vessels and aggravating CAA.So decreased clearance of Aβ in blood vessels plays a crucial role in the development of CAA and AD,and identification of the molecular pathways involved will provide new targets for treatment.In this review,we mainly describe the mechanisms of Aβ clearance through vessels,especially in terms of some proteins and receptors involved in this process.

Does the advantage of transcutaneous oximetry measurements in diabetic foot ulcer apply equally to free flap reconstruction?

BACKGROUND Transcutaneous oxygen pressure(TcpO2)is a precise method for determining oxygen perfusion in wounded tissues.The device uses either electrochemical or optical sensors.AIM To evaluate the usefulness of TcpO2 measurements on free flaps(FFs)in diabetic foot ulcers(DFUs).METHODS TcpO2 was measured in 17 patients with DFUs who underwent anterolateral thigh(ALT)-FF surgery and compared with 30 patients with DFU without FF surgery.RESULTS Significant differences were observed in the ankle-brachial index;duration of diabetes;and haemoglobin,creatinine,and C-reactive protein levels between the two groups.TcpO2 values were similar between two groups except on postoperative days 30 and 60 when the values in the ALT-FF group remained<30 mmHg and did not increase>50 mmHg.CONCLUSION Even if the flap is clinically stable,sympathectomy due to adventitia stripping during anastomosis and arteriovenous shunt progression due to diabetic polyneuropathy could lead to low TcpO2 values in the ALT-FF owing to its thick fat tissues,which is supported by the slow recovery of the sympathetic tone following FF.Therefore,TcpO2 measurements in patients with DFU who underwent FF reconstruction may be less accurate than in those who did not.

The relationship between amyloid-beta and brain capillary endothelial cells in Alzheimer's disease

Neurovascular dysfunction,as an integral part of Alzheimer's disease,may have an important influence on the onset and progression of chronic neurodegenerative processes.The bloodbrain barrier(BBB)pathway is one of the main pathways that mediates the clearance of amyloidbeta(Aβ)in the brain parenchyma.A large number of studies have shown that receptors and ATPbinding cassette transporte rs expressed on endothelial cells play an important role in Aβtransport across the BBB,but the specific mechanism is not clear.In this review,we summarize the possible mechanisms of Aβproduction and clearance,and in particular the relationship between Aβand brain capillary endothelial cells.Aβis produced by abnormal cleavage of the amyloid precursor protein via amyloidogenic processing under pathological conditions.Dys regulation of Aβclearance is considered to be the main reason for the massive accumulation of Aβin the brain parenchyma.Several pathways mediating Aβclearance from the brain into the periphery have been identified,including the BBB pathway,the blood-cerebros pinal fluid barrier and arachnoid granule pathway,and the lymphoidrelated pathway.Brain ca pilla ry endothelial cells are the key components of Aβclearance mediated by BBB.Receptors(such as LRP1,RAGE,and FcRn)and ATP-binding cassette transporters(such as P-gp,ABCA1,and ABCC1)expressed on endothelial cells play a critical role in Aβtranscytosis across the BBB.The toxic effects of Aβcan induce dysregulation of receptor and transpo rter expression on endothelial cells.Excessive Aβexerts potent detrimental cerebrovascular effects by promoting oxidative stress,inducing chronic inflammation,and impairing endothelial structure and functions.All of these are main causes for the reduction in Aβclearance across the BBB and the accumulation of Aβin the brain parenchyma.Therefo re,studies on the intera ctions between Aβand brain capillary endothelial cells,including their receptors and transporters,studies on inhibition of the toxic effects of Aβon endothelial cells,and studies on promoting the ability of endothelial cells to mediate Aβclearance may provide new therapeutic strategies for Aβclearance in Alzheimer's disease.

Can mouse models mimic sporadic Alzheimer’s disease?

Alzheimer’s disease(AD)is a progressive neurodegenerative disorder and the most common form of dementia worldwide.As age is the main risk factor,>97%of all AD cases are of sporadic origin,potentiated by various risk factors associated with life style and starting at an age>60 years.Only<3%of AD cases are of genetic origin caused by mutations in the amyloid precursor protein or Presenilins 1 or 2,and symptoms already start at an age<30 years.In order to study progression of AD,as well as therapeutic strategies,mouse models are state-of-the-art.So far many transgenic mouse models have been developed and used,with mutations in the APP or presenilin or combinations(3×Tg,5×Tg).However,such transgenic mouse models more likely mimic the genetic form of AD and no information can be given how sporadic forms develop.Several risk genes,such as Apolipoprotein E4 and TREM-2 enhance the risk of sporadic AD,but also many risk factors associated with life style(e.g.,diabetes,hypercholesterolemia,stress)may play a role.In this review we discuss the current situation regarding AD mouse models,and the problems to develop a sporadic mouse model of AD.