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1.
Arq. neuropsiquiatr ; 81(12): 1070-1076, Dec. 2023. tab
Article in English | LILACS-Express | LILACS | ID: biblio-1527915

ABSTRACT

Abstract Background Alzheimer's disease (AD) was described in 1907, and since then it changed from a relatively rare condition to one of the most prevalent diseases. Objective To describe the evolution of the notions of dementias and AD, and to investigate the reasons for the increase in scientific interest in AD. Methods A historical analysis was carried out on knowledge about dementia, the site of mental activity, the relationships between brain diseases and mental activity, and on the advances in research about AD, since its discovery until the publication of the amyloid cascade hypothesis in 1992. A search was carried out in the National Library of Medicine (PubMed) for scientific articles that included the terms dementia or AD over 50 years, from 1972 to 2021. Results The scientific research on AD increased from 615 papers with the term AD in the first decade (1972-1981), to 100,028 papers in the last decade (2012-2021): an increase of 162.6 times whereas publications with the term dementia increased 28.6 times in the same period. In the 1960s and 1970s, a consensus was reached that AD is responsible for the majority of cases of dementia previously known as senile dementia. In the 1980s, beta-amyloid peptide was identified in the core of the senile plaque, hyperphosphorylated tau protein was found in neurofibrillary tangles, and a mutation was discovered in a hereditary form of AD. Conclusion The expansion of the concept of AD to include senile dementia, and the discoveries that occurred in the 1980s greatly expanded research in AD.


Resumo Antecedentes A doença de Alzheimer (DA) foi descrita em 1907 e, desde então, deixou de ser relativamente rara para se tornar uma das doenças mais prevalentes. Objetivo Descrever a evolução das noções sobre demências e DA e investigar as razões do aumento do interesse científico pela DA. Métodos Foi realizada uma análise histórica dos conhecimentos sobre demência, o local da atividade mental, as relações entre doenças cerebrais e a atividade mental, e sobre os avanços na pesquisa sobre a DA, desde a sua descoberta até a publicação da hipótese da cascata amiloide em 1992. Foi realizada uma busca na Biblioteca Nacional de Medicina dos Estados Unidos da América (PubMed) por artigos científicos que incluíssem os termos demência ou DA nos 50 anos, de 1972 a 2021. Resultados A pesquisa científica sobre DA aumentou de 615 artigos com o termo doença de Alzheimer na primeira década (1972-1981), para 100.028 artigos na última década (2012-2021): um aumento de 162,6 vezes enquanto as publicações com o termo demência aumentaram 28,6 vezes no mesmo período. Nas décadas de 1960 e 1970, chegou-se a um consenso de que a DA é responsável pela maioria dos casos de demência, anteriormente conhecida como demência senil. Na década de 1980, o peptídeo beta-amiloide foi identificado no núcleo da placa senil, a proteína tau hiperfosforilada foi encontrada em emaranhados neurofibrilares e uma mutação foi descoberta em uma forma hereditária de DA. Conclusão A expansão do conceito de DA para incluir a demência senil e as descobertas ocorridas na década de 1980 ampliaram enormemente a pesquisa em DA.

2.
Rev. Hosp. Ital. B. Aires (En línea) ; 43(4): 209-213, dic. 2023.
Article in Spanish | LILACS, UNISALUD, BINACIS | ID: biblio-1537564

ABSTRACT

La amiloidosis siempre ha representado un desafío diagnóstico. En el año 2020, el Grupo de Estudio de Amiloidosis (GEA), confeccionó la Guía de Práctica Clínica para el Diagnóstico de Amiloidosis. Nuevas líneas de investigación se han desarrollado posteriormente. Esta revisión narrativa tiene como intención explorar el estado del arte en el diagnóstico de la amiloidosis. En pacientes con amiloidosis se recomienda la tipificación de la proteína mediante espectrometría de masa, técnica de difícil ejecución por requerir de microdisectores láser para la preparación de la muestra. Algunas publicaciones recientes proponen otros métodos para obtener la muestra de amiloide que se va a analizar, permitiendo prescindir de la microdisección. Por otra parte, en pacientes con Amiloidosis ATTR confirmada, la recomendación de secuenciar el gen amiloidogénico se encontraba destinada a los casos sospechosos de ATTR hereditaria (ATTRv,), pero actualmente esta se ha extendido a todos los pacientes sin importar la edad. En lo que respecta a los estudios complementarios orientados al diagnóstico de compromiso cardíaco, se ha propuesto el uso de la inteligencia artificial para su interpretación, permitiendo la detección temprana de la enfermedad y el correcto diagnóstico diferencial. Para el diagnóstico de neuropatía, las últimas publicaciones proponen el uso de la cadena ligera de neurofilamento sérica, que también podría resultar un indicador útil para seguimiento. Finalmente, con referencia a la amiloidosis AL, la comunidad científica se encuentra interesada en definir qué características determinan el carácter amiloidogénico de las cadenas livianas. La N-glicosilación de dichas proteínas impresiona ser uno de los determinantes en cuestión. (AU)


Amyloidosis has always represented a diagnostic challenge. In 2020, the Amyloidosis Study Group (ASG) developed the "Clinical Practice Guideline for the Diagnosis of Amyloidosis". New lines of research have subsequently emerged. This narrative review aims to explore the state of the art in the diagnosis of amyloidosis diagnosis. In patients with amyloidosis, protein typing by mass spectrometry is recommended, a technique hard to perform because it requires laser microdissection for sample preparation. Recent publications propose other methods to obtain the amyloid sample to be analyzed, making it possible to dispense with microdissection. On the other hand, in patients with confirmed TTR amyloidosis (aTTR), the recommendation to sequence the amyloidogenic gene was intended for suspected cases of hereditary aTTR but has now been extended to all patients regardless of age. (AU)


Subject(s)
Humans , Amyloid Neuropathies, Familial/diagnosis , Early Diagnosis , Amyloidosis/diagnosis , Mass Spectrometry , Biopsy , Glycosylation , Artificial Intelligence , Magnetic Resonance Imaging , Sequence Analysis, DNA , Practice Guidelines as Topic , Diagnosis, Differential , Electrocardiography , High-Throughput Nucleotide Sequencing
3.
Rev. gastroenterol. Perú ; 43(4)oct. 2023.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1536365

ABSTRACT

La amiloidosis intestinal es una enfermedad sistémica rara y subdiagnosticada, la cual se caracteriza por el depósito extracelular de proteínas que se agrupan en fibras amiloides. Esta entidad es infrecuente y suele ser una forma de presentación en el contexto de una amiloidosis sistémica, cuyo diagnóstico se basa en la presencia a amiloide en la histología. La clínica suele ser inespecífica; diarrea crónica, pérdida de peso, dolor y distensión abdominal; siendo la hemorragia digestiva una manifestación muy poco frecuente. Se presenta el caso de una mujer de 61 años con clínica de baja de peso, distención abdominal, náuseas, vómitos y melena. En la tomografía se evidenció un engrosamiento mural de asas yeyunales con captación de contraste, hallazgo que se corroboró con enteroscopia anterógrada a doble balón en el cual se evidenciaron múltiples úlceras en yeyuno, signos de atrofia, friabilidad y dilatación de luz yeyunal. En la anatomía patológica se aprecia arquitectura vellositaria distorsionada y ulcerada con histoquímica positiva a Rojo Congo e inmunohistoquímica lambda (+++). Además, se realizó aspirado de médula ósea y biopsia de hueso compatible con infiltración de mieloma múltiple monoclonal a cadena Lambda. Durante la estancia hospitalaria la paciente cursó con complicaciones como la desnutrición crónica, infección recurrente y varios episodios de suboclusión intestinal; caracterizada por neumatosis intestinal; debido a múltiples episodios de estas complicaciones la paciente fallece. Dentro de la práctica clínica en gastroenterología la amiloidosis intestinal como parte del diagnóstico diferencial de la hemorragia digestiva alta es infrecuente, por lo que los antecedentes de diagnóstico de mieloma múltiple u otras gammapatías monoclonales asociadas a cadenas ligeras es crucial para un diagnóstico precoz y tratamiento adecuado.


Intestinal amyloidosis is a rare and underdiagnosed systemic disease, which is characterized by the extracellular deposition of proteins that are grouped into amyloid fibers. This entity is rare and is usually a form of presentation in the context of systemic amyloidosis, the diagnosis of which is based on the presence of amyloid in histology. The clinic is usually non-specific; chronic diarrhea, weight loss, abdominal pain and bloating; Gastrointestinal bleeding is a very rare manifestation. The case of a 61-year-old woman with symptoms of weight loss, abdominal distension, nausea, vomiting and long hair is presented. Tomographically, a wall thickening of jejunal loops with contrast uptake was evidenced, a finding that was corroborated by a double-balloon anterograde stereoscopy in which multiple were evidenced. The pathology shows distorted and ulcerated villous architecture with positive histochemistry for Congo Red and LAMBDA (+++) immunohistochemistry. In addition, bone marrow aspirate and bone biopsy compatible with infiltration of Lambda chain monoclonal multiple myeloma were performed. During the hospital stay, the patient developed complications such as chronic malnutrition, recurrent infection and several episodes of intestinal subocclusion; characterized by intestinal pneumatosis; due to multiple episodes of these complications, the patient died. Within clinical practice in gastroenterology, intestinal amyloidosis as part of the differential diagnosis of upper gastrointestinal bleeding is infrequent, so a history of diagnosis of multiple myeloma or other monoclonal gammopathy associated with light chains is crucial for early diagnosis and adequate treatment.

4.
Article | IMSEAR | ID: sea-225533

ABSTRACT

Atraumatic Non-aneurysmal sulcal subarachnoid hemorrhage is very rare. Sulcal subarachnoid hemorrhage (sSAH) is characterized by isolated bleeding in one or a few adjacent sulci. Central sulcus hemorrhage is a rare imaging finding. There are many causes for sSAH. In older patients, sSAH is due to Cerebral Amyloid Angiopathy (CAA), while in younger patients, reversible cerebral vasoconstriction syndrome (RCVS) is the most frequent etiology. Imaging studies help in the evaluation of sSAH. We report a rare case of an isolated central sulcus hemorrhage on computed tomography. sSAH usually occur on the side with acute ischemic stroke, and it is unusual for sSAH to occur on the opposite side of the infarct territory, but in our case sSAH occurred on opposite side, but after a gap of 3 years.

5.
Article | IMSEAR | ID: sea-222298

ABSTRACT

Transient focal neurological episodes, also called amyloid spells occur as recurrent, transient episodes of spreading paresthesia seen in 14% of cerebral amyloid angiopathy (CAA) patients. An 81-year-old gentleman with coronary artery disease and a left ventricular clot was on anticoagulant treatment. He presented with three episodes of tingling in the left fingers spreading to the left arm and left leg, each lasting for 10 min. Magnetic resonance imaging of the brain with susceptibility imaging showed convexity hemorrhage, and curvilinear blooming in sulcal spaces of the right cerebral convexity and left precuneus. Warfarin was stopped. He was treated with clobazam, aspirin, and atorvastatin. He improved, so was discharged after 2 days. Amyloid spells can be confused with transient ischemic attack (TIA) or its mimics and the treatment given for TIA can lead to intracranial hemorrhage in CAA patients. Radiological features aid in the diagnosis of CAA and antiplatelets need to be administered cautiously in patients with suspected TIA.

6.
Arq. neuropsiquiatr ; 81(3): 308-321, Mar. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1439438

ABSTRACT

Abstract Hereditary transthyretin amyloidosis with peripheral neuropathy (ATTRv-PN) is an autosomal dominant inherited sensorimotor and autonomic polyneuropathy with over 130 pathogenic variants identified in the TTR gene. Hereditary transthyretin amyloidosis with peripheral neuropathy is a disabling, progressive and life-threatening genetic condition that leads to death in ~ 10 years if untreated. The prospects for ATTRv-PN have changed in the last decades, as it has become a treatable neuropathy. In addition to liver transplantation, initiated in 1990, there are now at least 3 drugs approved in many countries, including Brazil, and many more are being developed. The first Brazilian consensus on ATTRv-PN was held in the city of Fortaleza, Brazil, in June 2017. Given the new advances in the area over the last 5 years, the Peripheral Neuropathy Scientific Department of the Brazilian Academy of Neurology organized a second edition of the consensus. Each panelist was responsible for reviewing the literature and updating a section of the previous paper. Thereafter, the 18 panelists got together virtually after careful review of the draft, discussed each section of the text, and reached a consensus for the final version of the manuscript.


Resumo Polineuropatia amiloidótica familiar associada a transtirretina (ATTRv-PN) é uma polineuropatia sensitivo-motora e autonômica hereditária autossômica dominante com mais de 130 variantes patogênicas já identificadas no gene TTR. A ATTRv-PN é uma condição genética debilitante, progressiva e que ameaça a vida, levando à morte em ~ 10 anos se não for tratada. Nas últimas décadas, a ATTRv-PN se tornou uma neuropatia tratável. Além do transplante de fígado, iniciado em 1990, temos agora 3 medicamentos modificadores de doença aprovados em muitos países, incluindo o Brasil, e muitas outras medicações estão em desenvolvimento. O primeiro consenso brasileiro em ATTRv-PN foi realizado em Fortaleza em junho de 2017. Devido aos novos avanços nesta área nos últimos 5 anos, o Departamento Científico de Neuropatias Periféricas da Academia Brasileira de Neurologia organizou uma segunda edição do consenso. Cada panelista ficou responsável por rever a literatura e atualizar uma parte do manuscrito. Finalmente, os 18 panelistas se reuniram virtualmente após revisão da primeira versão, discutiram cada parte do artigo e chegaram a um consenso sobre a versão final do manuscrito.

7.
Indian Heart J ; 2023 Feb; 75(1): 73-76
Article | IMSEAR | ID: sea-220962

ABSTRACT

Limited data exists on patients with cardiac amyloidosis (CA) in India, due to underdiagnosis and late presentation. We present single centre data from 13 patients over a 4 year period with a median age of 65 years. A majority presented with symptomatic heart failure (69%) and eight patients had confirmed AL amyloidosis. At the end of the follow up period, 46% patients died, with 30% of the overall cohort dead within six months. Among the survivors, 71% continue to have NYHA grade III/IV symptoms. A suggested algorithm for earlier diagnosis in resource constrained settings is also presented.

8.
Chinese Journal of Postgraduates of Medicine ; (36): 706-710, 2023.
Article in Chinese | WPRIM | ID: wpr-991081

ABSTRACT

Objective:To investigate the effect of acupoint stimulation assisted anesthesia on the agitation during recovery and the levels of serum opioids (Opiorphin) and amyloid A (SAA) in elderly patients after hip fracture surgery.Methods:Eighty-six older patients who underwent hip fracture surgery in Shaoxing Second Hospital from February 2020 to September 2021 were randomly divided into the routine group and the research group, each with 43 patients. They were given acupoint sham stimulation and acupoint stimulation respectively, and the general indexes of the two groups, recovery quality, cognitive function and changes in serum Opiorphin and SAA levels were compared.Results:There were no differences in operation time, anesthesia time, recovery time and intraoperative blood transfusion between the two groups ( P>0.05). The dosage of remifentanil in the research group was significantly lower than that in the routine group: (270.64 ± 17.62) μg vs. (291.82 ± 23.34) μg, P<0.05. The incidence of agitation during the recovery period in the research group was significantly lower than that in the routine group: 13.95% (6/43) vs. 48.84% (21/43), P<0.05. The mini-mental state examination (MMSE) scores in the research group at 12, 24 and 48 h after operation were significantly higher than those in the routine group: (22.80 ± 2.04) scores vs. (19.31 ± 3.61) scores, (24.92 ± 2.44) scores vs. (21.49 ± 3.58) scores, (26.73 ± 2.57) scores vs. (24.23 ± 3.95) scores, there were statistical differences ( P<0.05). The serum Opiorphin level at 24 h after operation in the research group was higher than that in the routine group: (32.74 ± 8.57) mg/L vs. (25.40 ± 6.36) mg/L; and the SAA level was lower than that in the routine group: (157.36 ± 10.24) mg/L vs. (204.37 ± 15.56) mg/L, there were statistical differences ( P<0.05). Conclusions:Acupoint stimulation adjuvant anesthesia can reduce the occurrence of agitation during the recovery period of elderly patients with hip fracture, reduce the dosage of anesthetics, reduce postoperative cognitive impairment, regulate serum Opiorphin and SAA levels, and help early postoperative recovery.

9.
International Journal of Cerebrovascular Diseases ; (12): 378-383, 2023.
Article in Chinese | WPRIM | ID: wpr-989242

ABSTRACT

Cerebral amyloid angiopathy (CAA) is a common cerebral small vessel disease, mainly caused by β-amyloid deposition on the small vessels less than 200 μm in diameter in cortex and leptomeninges. CAA is a major cause of spontaneous intracerebral hemorrhage in the elderly, especially lobar location. Early symptoms are insidious, and as the disease progress, they manifest as cerebral hemorrhage, cognitive decline, transient focal neurological episodes, cerebral infarction, epilepsy, headache, etc. MRI revealed that CAA is a disease in which bleeding and ischemia coexist, and even inflammation and immune responses are involved. MRI findings of CAA include cerebral hemorrhage, cerebral microbleeds, convexity subarachnoid hemorrhage and cortical superficial siderosis, cortical microinfarcts, CAA-associated inflammation, white matter hyperintensities, enlarged perivascular spaces, cerebral atrophy and lacune, etc. The same patient often has several of the above manifestations, and each manifestation has different specificity for the diagnosis of CAA. The rapid development of MRI technology has led to the improvement of the diagnostic level of CAA, and it is of great clinical significance to understand these imaging findings. This article reviews the MRI findings of sporadic CAA.

10.
International Journal of Cerebrovascular Diseases ; (12): 292-297, 2023.
Article in Chinese | WPRIM | ID: wpr-989227

ABSTRACT

Optical coherence tomography-based angiography (OCTA) is a novel non-invasive technique for quantitatively evaluating retinal microvascular perfusion. Due to the similar embryonic origin, anatomical characteristics, and physiological characteristics of the retina and cerebral small vessels, changes in retinal microvasculature may provide a new perspective for studying the mechanisms of cerebral small vessel diseases. This article summarizes the application of OCTA in cerebrovascular diseases, aiming to evaluate whether OCTA can become an effective tool for early prediction of the occurrence of cerebrovascular disease and monitoring disease changes.

11.
International Journal of Cerebrovascular Diseases ; (12): 146-150, 2023.
Article in Chinese | WPRIM | ID: wpr-989204

ABSTRACT

Cerebral small vessel disease (CSVD) is an important cause of ischemic stroke and vascular dementia, which brings heavy burden to families and society. The prevention and treatment of CSVD has always been a research hotspot, but its pathogenesis is still not completely clear. This article reviews the pathogenesis of CSVD, including chronic cerebral hypoperfusion, blood-brain barrier dysfunction, vascular endothelial dysfunction, interstitial fluid reflux disorder, inflammatory response, and genetic factors, in order to provide more sufficient theoretical basis for early intervention and treatment of CSVD.

12.
Journal of Medical Biomechanics ; (6): E236-E241, 2023.
Article in Chinese | WPRIM | ID: wpr-987941

ABSTRACT

Objective To explore the cooperative effect from β-propensity of amyloidogenic peptides on amyloid nucleation and its related products. Methods Based on a coarse-grained model for amyloidogenic peptides containing two states ( a soluble state and a β-sheet-forming state), with the consideration of two kinds of cooperative effects on β-propensity of peptides ( inhibiting and promoting the conformational conversion of peptides), the regulation of cooperative effects from amyloidogenic peptides on amyloid nucleation was analyzed through Monte Carlo simulations. Results In the case of the cooperative effect inhibiting the conformational conversion of peptides, amyloid nucleation occurred only within a certain interval of the peptide concentration, as well as inside the oligomers with certain sizes. Besides, the coexistence of on-pathway and off-pathway oligomers was observed. In the case of the cooperative effect promoting the conformational conversion of peptides, the β-sheet protofibril could be observed at physiological concentration as low as 4 μmol / L. Conclusions In this study, a more realistic coarse-grained model for amyloidogenic peptides was developed by introducing the cooperative effects of local concentration on β-propensity of amyloidogenic peptides, with observation of some intriguing phenomena not reported in previous simulations. The research findings not only improve current understandings about the mechanism of amyloid formation, but also provide theoretic references for the therapeutic strategies for curing neurodegenerative diseases

13.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 195-202, 2023.
Article in Chinese | WPRIM | ID: wpr-964960

ABSTRACT

ObjectiveTo explore the amelioration of cognitive dysfunction in diabetes mellitus (DM) by Jianpi Qinghua prescription (JPQH) based on type 2 diabetes (T2DM) model rats. MethodFifty healthy male Wistar rats of SPF grade were randomly divided into control group (n=10) and experimental group (n=40). The rats in the control group were fed conventionally, while those in the experimental group were fed on a high-sugar, high-fat diet for six weeks and administered with streptozotocin (STZ) for the induction of the DM model. The model rats were randomly divided into model group, sitagliptin group (1.2 g·L-1), pioglitazone group (0.8 g·L-1), and JPQH group (1.3 g·mL-1), with 10 rats in each group. After six weeks of drug intervention, the changes in body weight, blood glucose, and other related indexes of each group were recorded. Enzyme-linked immunosorbent assay (ELISA) was performed to detect the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in the peripheral blood and brain. The Morris water maze test was used to evaluate the cognitive function in rats. Hematoxylin-eosin (HE) staining was used to observe the pathological morphology of the hippocampal CA region. The amyloid β-protein 40 (Aβ40) level was detected by immunohistochemistry. The protein expression of t-tau and p-tau in hippocampal neurons of rats was detected by Western blot. ResultCompared with blank group, the body weight of model group was significantly decreased (P<0.05), blood glucose level was significantly increased (P<0.01), inflammatory cytokines TNF-α and IL-1β were increased (P<0.05), learning and spatial ability were significantly decreased (P<0.01), the arrangement of hippocampal cells was loose and disordered, and the intercellular space was significantly increased. The number of cells decreased significantly, and the expression of Aβ40 increased significantly. and increased t-tau and p-tau protein content in the hippocampus (P<0.01). Compared with model group, the JPQH group showed reduced blood glucose (P<0.01), decreased TNF-α and IL-1β levels in the peripheral blood and cerebrospinal fluid (P<0.05), a downward trend of IL-6 without a statistical difference, improved learning and spatial memory ability (P<0.01), densely arranged cells in the hippocampal CA1 area, increased cell number, reduced Aβ40 expression, and decreased p-tau protein expression (P<0.05). ConclusionJPQH can prevent cognitive dysfunction in DM by reducing inflammatory factor levels, decreasing neurotoxicity caused by Aβ40 deposition, and inhibiting hyperphosphorylation of tau protein in DM rats.

14.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 216-221, 2023.
Article in Chinese | WPRIM | ID: wpr-962644

ABSTRACT

Based on the correlation between Qi and blood in traditional Chinese medicine, the collateral disease theory puts forward that the Qi-collateral go hand in hand with the vessel-collateral of the brain, and to be as close as lips to teeth in structure and function, which is an important basis for the function of brain governing mind. And this theory proposes that deficiency/stagnancy of collateral-Qi, stagnation of collaterals and loss of consciousness are the main pathogenesis of Alzheimer's disease(AD), which is different from the research strategy of modern medicine focusing on neurons. It is suggested that it is necessary to treat AD from two aspects, including neuronal protection(elimination of pathological products such as β-amyloid and phosphorylated tau protein) and cerebral microvascular protection(protection of cerebral microvascular structure and function, promotion of therapeutic angiogenesis and increase of cerebral blood flow. Tongxinluo capsules is a representative drug for dredging collaterals developed under the guidance of the therapeutic principle of collaterals need circulation, it can protect microvessels and play a neuroprotective role mediated by vascular protection. Clinical studies have confirmed that Tongxinluo capsules can effectively treat AD, vascular dementia and cognitive impairment related diseases, which can provide new ideas and effective treatment ways to prevent and treat AD from neurovascular protection in a comprehensive manner.

15.
Chinese Journal of Biotechnology ; (12): 1633-1643, 2023.
Article in Chinese | WPRIM | ID: wpr-981159

ABSTRACT

The multiple-step cleavage of amyloid precursor protein (APP) generates amyloid-β peptides (Aβ), highly toxic molecules causing Alzheimer's disease (AD). The nonspecific cleavage between the transmembrane region of APP (APPTM) and γ-secretase is the key step of Aβ generation. Reconstituting APPTM under physiologically-relevant conditions is crucial to investigate how it interacts with γ-secretase and for future AD drug discovery. Although producing recombinant APPTM was reported before, the large scale purification was hindered by the use of biological protease in the presence of membrane protein. Here, we expressed recombinant APPTM in Escherichia coli using the pMM-LR6 vector and recovered the fusion protein from inclusion bodies. By combining Ni-NTA chromatography, cyanogen bromide cleavage, and reverse phase high performance liquid chromatography (RP-HPLC), isotopically-labeled APPTM was obtained in high yield and high purity. The reconstitution of APPTM into dodecylphosphocholine (DPC) micelle generated mono dispersed 2D 15N-1H HSQC spectra in high quality. We successfully established an efficient and reliable method for the expression, purification and reconstruction of APPTM, which may facilitate future investigation of APPTM and its complex in more native like membrane mimetics such as bicelle and nanodiscs.


Subject(s)
Humans , Amyloid beta-Protein Precursor/chemistry , Micelles , Amyloid Precursor Protein Secretases/metabolism , Magnetic Resonance Spectroscopy , Recombinant Proteins
16.
Neuroscience Bulletin ; (6): 1117-1130, 2023.
Article in English | WPRIM | ID: wpr-982468

ABSTRACT

Resveratrol (RES), a natural polyphenolic phytochemical, has been suggested as a putative anti-aging molecule for the prevention and treatment of Alzheimer's disease (AD) by the activation of sirtuin 1 (Sirt1/Sir2). In this study, we tested the effects of RES and Sirt1/Sir2 on sleep and courtship memory in a Drosophila model by overexpression of amyloid precursor protein (APP), whose duplications and mutations cause familial AD. We found a mild but significant transcriptional increase of Drosophila Sir2 (dSir2) by RES supplementation for up to 17 days in APP flies, but not for 7 days. RES and dSir2 almost completely reversed the sleep and memory deficits in APP flies. We further demonstrated that dSir2 acts as a sleep promotor in Drosophila neurons. Interestingly, RES increased sleep in the absence of dSir2 in dSir2-null mutants, and RES further enhanced sleep when dSir2 was either overexpressed or knocked down in APP flies. Finally, we showed that Aβ aggregates in APP flies were reduced by RES and dSir2, probably via inhibiting Drosophila β-secretase (dBACE). Our data suggest that RES rescues the APP-induced behavioral deficits and Aβ burden largely, but not exclusively, via dSir2.


Subject(s)
Animals , Alzheimer Disease/metabolism , Amyloid beta-Peptides , Amyloid beta-Protein Precursor/metabolism , Drosophila/physiology , Drosophila Proteins/metabolism , Resveratrol/pharmacology , Sirtuin 1 , Sleep
17.
Chinese journal of integrative medicine ; (12): 448-458, 2023.
Article in English | WPRIM | ID: wpr-982293

ABSTRACT

OBJECTIVE@#To investigate the molecular mechanisms underlying the beneficial effect of electroacupuncture (EA) in experimental models of Alzheimer's disease (AD) in vivo.@*METHODS@#Senescence-accelerated mouse prone 8 (SAMP8) mice were used as AD models and received EA at Yingxiang (LI 20, bilateral) and Yintang (GV 29) points for 20 days. For certain experiments, SAMP8 mice were injected intravenously with human fibrin (2 mg). The Morris water maze test was used to assess cognitive and memory abilities. The changes of tight junctions of blood-brain barrier (BBB) in mice were observed by transmission electron microscope. The expressions of fibrin, amyloid- β (Aβ), and ionized calcium-binding adapter molecule 1 (IBa-1) in mouse hippocampus (CA1/CA3) were detected by reverse transcription-quantitative polymerase chain reaction (qRT-PCR), Western blot or immunohistochemical staining. The expression of fibrin in mouse plasma was detected by enzyme-linked immunosorbent assay. The expressions of tight junction proteins zonula occludens-1 and claudin-5 in hippocampus were detected by qRT-PCR and immunofluorescence staining. Apoptosis of hippocampal neurons was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining.@*RESULTS@#Fibrin was time-dependently deposited in the hippocampus of SAMP8 mice and this was inhibited by EA treatment (P<0.05 or P<0.01). Furthermore, EA treatment suppressed the accumulation of Aβ in the hippocampus of SAMP8 mice (P<0.01), which was reversed by fibrin injection (P<0.05 or P<0.01). EA improved SAMP8 mice cognitive impairment and BBB permeability (P<0.05 or P<0.01). Moreover, EA decreased reactive oxygen species levels and neuroinflammation in the hippocampus of SAMP8 mice, which was reversed by fibrin injection (P<0.05 or P<0.01). Mechanistically, EA inhibited the promoting effect of fibrin on the high mobility group box protein 1 (HMGB1)/toll-like receptor 4 (TLR4) and receptor for advanced glycation end products (RAGE)/nicotinamide adenine dinucleotide phosphate (NADPH) signaling pathways (P<0.01).@*CONCLUSION@#EA may potentially improve cognitive impairment in AD via inhibition of fibrin/A β deposition and deactivation of the HMGB1/TLR4 and RAGE/NADPH signaling pathways.


Subject(s)
Mice , Humans , Animals , NADP/metabolism , Toll-Like Receptor 4 , HMGB1 Protein/metabolism , Receptor for Advanced Glycation End Products/metabolism , Blood-Brain Barrier/metabolism , Neuroinflammatory Diseases , Electroacupuncture , Alzheimer Disease/therapy , Hippocampus/metabolism , Amyloid beta-Peptides/metabolism
18.
Rev. bras. oftalmol ; 82: e0068, 2023. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1529924

ABSTRACT

ABSTRACT Amyloidosis is a rare disease in which ocular involvement may occur as an isolated event or associated with a systemic disease. This paper describes two clinical cases of ophthalmologic manifestations of amyloidosis: a bilateral eyelid lesion similar to xanthelasma and tarsal conjunctival disease similar to follicular conjunctivitis. The anatomopathological analysis confirmed the diagnosis.


RESUMO A amiloidose é uma doença rara que pode ter o acometimento ocular como forma isolada ou estar associada a doenças sistêmicas. Neste relato, são descritos dois casos clínicos de alterações oftalmológicas da amiloidose: um que se manifestou por meio de lesão palpebral bilateral de aspecto similar ao xantelasma. O outro era uma afecção em conjuntiva tarsal, semelhante à conjuntivite folicular. O estudo anatomopatológico confirmou o diagnóstico.


Subject(s)
Humans , Male , Middle Aged
19.
Einstein (Säo Paulo) ; 21: eAO0251, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1440076

ABSTRACT

ABSTRACT Objective To compare serum amyloid A concentrations between overweight and eutrophic children and adolescents and to relate it to lipid profiles, glucose tolerance, and carotid intima-media thickness. Methods One hundred children and adolescents (mean age: 10.8±3.16 years) were included and divided into two groups: overweight and non-overweight. The following were evaluated: Z-score body mass index, carotid intima-media thickness, lipid metabolism biomarkers (lipid profile and apolipoproteins A1 and B), inflammatory biomarkers (ultra-sensitive C-reactive protein and serum amyloid A), and glucose homeostasis model assessment of insulin resistance. Results The groups were homogeneous in age, sex, and pubertal stage. Higher levels of triglycerides, apolipoprotein B, homeostasis model assessment of insulin resistance, ultrasensitive C-reactive protein, serum amyloid A, and carotid intima-media thickness were observed in the overweight group. In the multivariate analysis, age (OR=1.73; 95%CI: 1.16-2.60, p=0.007), Z-score body mass index (OR=3.76; 95%CI: 1.64-8.59, p=0.002), apolipoprotein-B (OR=1.1; 95%CI: 1.01-1.2, p=0.030), and carotid intima-media thickness (OR=5.00; 95%CI: 1.38-18.04, p=0.014) were independently associated with serum amyloid A levels above the fourth quartile of the studied sample (>9.4mg/dL). Conclusion Overweight children and adolescents had higher serum amyloid A concentrations than eutrophic children. There was an independent association between higher concentrations of serum amyloid A and Z-score, body mass index, apolipoprotein B, and carotid intima-media thickness, indicating the importance of this inflammatory biomarker in identifying the early risk of atherosclerosis.

20.
Braz. j. med. biol. res ; 56: e12443, 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1420763

ABSTRACT

Amyloid fibrils are characteristic of several disorders including Alzheimer's disease (AD), with no cure or preventive therapy. Diminishing amyloid deposits using aromatic compounds is an interesting approach toward AD treatment. The present study examined the anti-fibrillogenic effects of silibinin and trans-chalcone in vitro, in vivo, and in silico on insulin amyloids. In vitro incubation of insulin at 37°C for 24 h induced amyloid formation. Addition of trans-chalcone and silibinin to insulin led to reduced amounts of fibrils as shown by thioflavin S fluorescence and Congo red absorption spectroscopy, with a better effect observed for silibinin. In vivo bilateral injection of fibrils formed by incubation of insulin in the presence or absence of silibinin and trans-chalcone or insulin fibrils plus the compounds in rats' hippocampus was performed to obtain AD characteristics. Passive avoidance (PA) test showed that treatment with both compounds efficiently increased latency compared with the model group. Histological investigation of the hippocampus in the cornu ammonis (CA1) and dentate gyrus (DG) regions of the rat's brain stained with hematoxylin-eosin and thioflavin S showed an inhibitory effect on amyloid aggregation and markedly reduced amyloid plaques. In silico, a docking experiment on native and fibrillar forms of insulin provided an insight onto the possible binding site of the compounds. In conclusion, these small aromatic compounds are suggested to have a protective effect on AD.

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