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1.
ANZ J Surg ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101372

RESUMO

PURPOSE: Hounsfield unit density of biliary fluid on CT may be a useful clinical marker that has not been described in the literature. This method has been used to differentiate pyonephrosis from hydronephrosis in obstructed collecting systems of the kidney. We aimed to create a user-friendly technique to measure the density of the distal bile duct using CT. The bile duct density of cases with proven choledocholithiasis at ERCP were compared with those of a control group (no biliary pathology). METHODS: A total of 106 patients with proven choledocholithiasis at ERCP and 50 control patients were analysed. The distal bile duct density was calculated using the 4-point and max ellipse methods. Two blinded, independent investigators calculated the bile duct density. RESULTS: The HU is significantly higher in the presence of choledocholithiasis (P < 0.0001). Using the Youden index a cut-off value of 28.6 HU for the 4-point technique is useful to predict the presence of choledocholithiasis (Sensitivity 58%, Specificity 86%). CONCLUSION: Calculation of the distal bile duct density can differentiate choledocholithiasis from a control population. It may be useful alone or as a component of a scoring system to select patients more effectively for intervention. The improved use of CT may also decrease use of MRCP and reduce time to ERCP, which have potential cost benefits.

2.
J Infect Dis ; 230(1): e4-e16, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052718

RESUMO

BACKGROUND: Mutations present in emerging SARS-CoV-2 variants permit evasion of neutralization with prototype vaccines. A novel Omicron BA.1 subvariant-specific vaccine (NVX-CoV2515) was tested alone or as a bivalent preparation with the prototype vaccine (NVX-CoV2373) to assess antibody responses to SARS-CoV-2. METHODS: Participants aged 18 to 64 years immunized with 3 doses of prototype mRNA vaccines were randomized 1:1:1 to receive a single dose of NVX-CoV2515, NVX-CoV2373, or the bivalent mixture in a phase 3 study investigating heterologous boosting with SARS-CoV-2 recombinant spike protein vaccines. Immunogenicity was measured 14 and 28 days after vaccination for the SARS-CoV-2 Omicron BA.1 sublineage and ancestral strain. Safety profiles of vaccines were assessed. RESULTS: Of participants who received trial vaccine (N = 829), those administered NVX-CoV2515 (n = 286) demonstrated a superior neutralizing antibody response to BA.1 vs NVX-CoV2373 (n = 274) at day 14 (geometric mean titer ratio, 1.6; 95% CI, 1.33-2.03). Seroresponse rates were 73.4% (91/124; 95% CI, 64.7-80.9) for NVX-CoV2515 vs 50.9% (59/116; 95% CI, 41.4-60.3) for NVX-CoV2373. All formulations were similarly well tolerated. CONCLUSIONS: NVX-CoV2515 elicited a superior neutralizing antibody response against the Omicron BA.1 subvariant as compared with NVX-CoV2373 when administered as a fourth dose. Safety data were consistent with the established safety profile of NVX-CoV2373. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov (NCT05372588).


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/efeitos adversos , Adulto , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Masculino , Feminino , COVID-19/prevenção & controle , COVID-19/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos
3.
Lancet Infect Dis ; 24(6): 581-593, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460525

RESUMO

BACKGROUND: SARS-CoV-2 variants evade immunity despite vaccination with prototype COVID-19 vaccines or previous infection. The 2019nCoV-311 (part 2) study is evaluating immune responses after two booster doses of a vaccine containing the omicron BA.5 subvariant spike protein in adults previously vaccinated with a prototype mRNA vaccine. This interim analysis reports on day 28 immunogenicity and safety outcomes after one booster dose. METHODS: In this phase 3, randomised, observer-blinded study conducted at 35 sites in Australia, medically stable, previously COVID-19-vaccinated (mRNA-based; ≥three doses) adults aged 18 years or older were enrolled and randomly allocated (1:1:1; via an interactive web response system) to receive two doses of bivalent (NVX-CoV2373 + NVX-CoV2540; bivalent group), authorised prototype (NVX-CoV2373; prototype group), or BA.5 (NVX-CoV2540; BA.5 group) vaccine. Only blinded personnel performed study assessments or had participant contact to collect data after study vaccination. Participants received vaccines containing 5 µg SARS-CoV-2 recombinant spike protein and 50 µg Matrix-M adjuvant, administered via a 0·5 mL intramuscular injection (2·5 µg of NVX-CoV2373 plus 2·5 µg of NVX-CoV2540 for the bivalent vaccine, prepared on-site as a 1:1 mixture). The coprimary endpoints include day 28 neutralising antibody geometric mean titre (GMT) ratios (GMTRs) to omicron BA.5 and the ancestral strain, and seroresponse rates to BA.5, in the bivalent and prototype groups. These endpoints were calculated in the per-protocol analysis set, which was defined as participants who had received a vaccine dose, had baseline and day 28 immunogenicity data, and were PCR-negative for SARS-CoV-2, with no major protocol deviations. The primary objective was to determine the primary outcome (antibody responses), which consisted of three comparisons: superiority of the bivalent versus prototype vaccine for neutralising antibody GMT to BA.5 (ie, lower bound of the GMTR 95% CI >1·0); non-inferiority of neutralising antibody seroresponse rate to BA.5 (ie, lower bound of the seroresponse rate 95% CI >-5%); and non-inferiority of neutralising antibody GMT to the ancestral strain (ie, lower bound of GMTR 95% CI >0·67). This trial was registered at ClinicalTrials.gov, number NCT05372588. FINDINGS: Between March 22, 2023 and May 2, 2023, 837 participants were screened for eligibility and 766 were randomly allocated to receive the BA.5 (n=255), prototype (n=252), or bivalent (n=259) vaccine. After accounting for exclusions due to participants being baseline SARS-CoV-2-positive, having previous infection, or protocol deviations, the per-protocol analysis set included 694 participants (236 in BA.5 group, 227 in prototype group, and 231 in bivalent group). In this interim analysis (maximum follow-up 35 days after the first dose), the bivalent group, compared with the prototype group, had superior neutralising antibody responses to BA.5 (GMT 1017·8 [95% CI 891·0-1162·6] vs 515·1 [450·4-589·0]; GMTR 2·0 [1·69-2·33]) and a non-inferior seroresponse rate to BA.5 at day 28 (39·8% [33·5-46·5] vs 12·3% [8·4-17·3]; difference 27·5% [19·8-35·0]). The bivalent group also had non-inferior neutralising antibody responses to the ancestral strain (GMTR 1·0 [0·84-1·20]), compared with the prototype group. All vaccines were similarly well tolerated. INTERPRETATION: All three coprimary endpoints were met in part 2 of the ongoing 2019nCoV-311 study. These data support the development of monovalent and/or bivalent vaccines for the most currently circulating variants, to optimise protection. With no new safety findings, further investigation of omicron-based subvariant vaccines is supported by the evidence. FUNDING: Novavax.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunização Secundária , Imunogenicidade da Vacina , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Glicoproteína da Espícula de Coronavírus/imunologia , Masculino , COVID-19/prevenção & controle , COVID-19/imunologia , SARS-CoV-2/imunologia , Feminino , Imunização Secundária/métodos , Pessoa de Meia-Idade , Adulto , Anticorpos Antivirais/sangue , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Idoso , Austrália , Adulto Jovem
4.
Acta Pharmacol Sin ; 45(5): 900-913, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225393

RESUMO

Autophagy impairment is a key factor in Alzheimer's disease (AD) pathogenesis. TFEB (transcription factor EB) and TFE3 (transcription factor binding to IGHM enhancer 3) are nuclear transcription factors that regulate autophagy and lysosomal biogenesis. We previously showed that corynoxine (Cory), a Chinese medicine compound, protects neurons from Parkinson's disease (PD) by activating autophagy. In this study, we investigated the effect of Cory on AD models in vivo and in vitro. We found that Cory improved learning and memory function, increased neuronal autophagy and lysosomal biogenesis, and reduced pathogenic APP-CTFs levels in 5xFAD mice model. Cory activated TFEB/TFE3 by inhibiting AKT/mTOR signaling and stimulating lysosomal calcium release via transient receptor potential mucolipin 1 (TRPML1). Moreover, we demonstrated that TFEB/TFE3 knockdown abolished Cory-induced APP-CTFs degradation in N2aSwedAPP cells. Our findings suggest that Cory promotes TFEB/TFE3-mediated autophagy and alleviates Aß pathology in AD models.


Assuntos
Doença de Alzheimer , Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Modelos Animais de Doenças , Canais de Potencial de Receptor Transitório , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Autofagia/efeitos dos fármacos , Camundongos , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Humanos , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Camundongos Endogâmicos C57BL , Serina-Treonina Quinases TOR/metabolismo , Masculino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Transdução de Sinais/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/genética
5.
J Infect Dis ; 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37970668

RESUMO

BACKGROUND: Mutations present in emerging SARS-CoV-2 variants permit evasion of neutralization with prototype vaccines. A novel Omicron BA.1 subvariant-specific vaccine (NVX-CoV2515) was tested alone, or as a bivalent preparation in combination with the prototype vaccine (NVX-CoV2373), to assess antibody responses to SARS-CoV-2. METHODS: Participants aged 18 to 64 years immunized with 3 doses of prototype mRNA vaccines were randomized 1:1:1 to receive a single dose of NVX-CoV2515, NVX-CoV2373, or bivalent mixture in a phase 3 study investigating heterologous boosting with SARS-CoV-2 recombinant spike protein vaccines. Immunogenicity was measured 14 and 28 days after vaccination for the SARS-CoV-2 Omicron BA.1 sublineage and ancestral strain. Safety profiles of vaccines were assessed. RESULTS: Of participants who received trial vaccine (N = 829), those administered NVX-CoV2515 (n = 286) demonstrated superior neutralizing antibody response to BA.1 versus NVX-CoV2373 (n = 274) at Day 14 (geometric mean titer ratio [95% CI]: 1.6 [1.33, 2.03]). Seroresponse rates [n/N; 95% CI] were 73.4% [91/124; 64.7, 80.9] for NVX-CoV2515 versus 50.9% [59/116; 41.4, 60.3] for NVX-CoV2373. All formulations were similarly well-tolerated. CONCLUSIONS: NVX-CoV2515 elicited a superior neutralizing antibody response against the Omicron BA.1 subvariant compared with NVX-CoV2373 when administered as a fourth dose. Safety data were consistent with the established safety profile of NVX-CoV2373.

6.
Radiology ; 309(2): e222049, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38015082

RESUMO

HISTORY: A 7-year-old Chinese girl presented to a local hospital with a 5-day history of progressive right-sided hemiplegia, expressive aphasia, mild bulbar palsy, and reduced general responsiveness. At presentation, her Glasgow Coma Scale was 11/15 (E4 V1M6). Notably, she had two strokelike episodes approximately 7 and 3 months prior to the current episode, with headache, reduced movement, and numbness in the left hand. She also had an extensive medical history at a young age, including congenital mydriasis, patent ductus arteriosus with ligation, dysautonomia, low blood pressure, hypotonic bladder requiring intermittent catheterization, poor bowel transit, and gallstones. Her immunization record was up to date, and her development was otherwise unremarkable. Her parents and younger sibling were healthy. Her blood tests revealed a mildly increased venous lactate level at 2.3 mmol/L (normal range, 0.7-2.1 mmol/L), without acidosis. Results of a coagulopathy work-up (clotting profile and protein C, protein S, antithrombin 3, and fibrinogen levels) were normal. MRI and MR angiography of the brain were performed at presentation.


Assuntos
Permeabilidade do Canal Arterial , Doenças Musculares , Humanos , Feminino , Criança , Angiografia , Anticoagulantes , Músculo Liso
7.
Signal Transduct Target Ther ; 8(1): 404, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37867176

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the predominant impairment of neurons in the hippocampus and the formation of amyloid plaques, hyperphosphorylated tau protein, and neurofibrillary tangles in the brain. The overexpression of amyloid-ß precursor protein (APP) in an AD brain results in the binding of APP intracellular domain (AICD) to Fe65 protein via the C-terminal Fe65-PTB2 interaction, which then triggers the secretion of amyloid-ß and the consequent pathogenesis of AD. Apparently, targeting the interaction between APP and Fe65 can offer a promising therapeutic approach for AD. Recently, exosome, a type of extracellular vesicle with diameter around 30-200 nm, has gained much attention as a potential delivery tool for brain diseases, including AD, due to their ability to cross the blood-brain barrier, their efficient uptake by autologous cells, and their ability to be surface-modified with target-specific receptor ligands. Here, the engineering of hippocampus neuron cell-derived exosomes to overexpress Fe65, enabled the development of a novel exosome-based targeted drug delivery system, which carried Corynoxine-B (Cory-B, an autophagy inducer) to the APP overexpressed-neuron cells in the brain of AD mice. The Fe65-engineered HT22 hippocampus neuron cell-derived exosomes (Fe65-EXO) loaded with Cory-B (Fe65-EXO-Cory-B) hijacked the signaling and blocked the natural interaction between Fe65 and APP, enabling APP-targeted delivery of Cory-B. Notably, Fe65-EXO-Cory-B induced autophagy in APP-expressing neuronal cells, leading to amelioration of the cognitive decline and pathogenesis in AD mice, demonstrating the potential of Fe65-EXO-Cory-B as an effective therapeutic intervention for AD.


Assuntos
Doença de Alzheimer , Exossomos , Camundongos , Animais , Doença de Alzheimer/patologia , Exossomos/genética , Exossomos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Cognição , Neurônios/patologia
8.
J Neuroimmune Pharmacol ; 18(3): 509-528, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37682502

RESUMO

The autophagy-lysosomal pathway (ALP) is a major cellular machinery involved in the clearance of aggregated proteins in Alzheimer disease (AD). However, ALP is dramatically impaired during AD pathogenesis via accumulation of toxic amyloid beta (Aß) and phosphorylated-Tau (phospho-Tau) proteins in the brain. Therefore, activation of ALP may prevent the increased production of Aß and phospho-Tau in AD. Peroxisome proliferator-activated receptor alpha (PPARα), a transcription factor that can activate autophagy, and transcriptionally regulate transcription factor EB (TFEB) which is a key regulator of ALP. This suggests that targeting PPARα, to reduce ALP impairment, could be a viable strategy for AD therapy. In this study, we investigated the anti-AD activity of Caudatin, an active constituent of Cynanchum otophyllum (a traditional Chinese medicinal herb, Qing Yang Shen; QYS). We found that Caudatin can bind to PPARα as a ligand and augment the expression of ALP in microglial cells and in the brain of 3XTg-AD mice model. Moreover, Caudatin could activate PPARα and transcriptionally regulates TFEB-augmented lysosomal degradation of Aß and phosphor-Tau aggregates in AD cell models. Oral administration of Caudatin decreased AD pathogenesis and ameliorated the cognitive dysfunction in 3XTg-AD mouse model. Conclusively, Caudatin can be a potential AD therapeutic agent via activation of PPARα-dependent ALP.

9.
Int J Mol Sci ; 24(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37511539

RESUMO

Neuroinflammation is the precursor for several neurodegenerative diseases (NDDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Targeting neuroinflammation has emerged as a promising strategy to address a wide range of CNS pathologies. These NDDs still present significant challenges in terms of limited and ineffective diagnosis and treatment options, driving the need to explore innovative and novel therapeutic alternatives. Aptamers are single-stranded nucleic acids that offer the potential for addressing these challenges through diagnostic and therapeutic applications. In this review, we summarize diagnostic and therapeutic aptamers for inflammatory biomolecules, as well as the inflammatory cells in NDDs. We also discussed the potential of short nucleotides for Aptamer-Based Targeted Brain Delivery through their unique features and modifications, as well as their ability to penetrate the blood-brain barrier. Moreover, the unprecedented opportunities and substantial challenges of using aptamers as therapeutic agents, such as drug efficacy, safety considerations, and pharmacokinetics, are also discussed. Taken together, this review assesses the potential of aptamers as a pioneering approach for target delivery to the CNS and the treatment of neuroinflammation and NDDs.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doenças Neuroinflamatórias , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/patologia , Doença de Alzheimer/tratamento farmacológico , Encéfalo/patologia , Oligonucleotídeos/uso terapêutico
10.
Radiology ; 308(1): e222048, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37489988

RESUMO

HISTORY: A 7-year-old Chinese girl presented to a local hospital with a 5-day history of progressive right-sided hemiplegia, expressive aphasia, mild bulbar palsy, and reduced general responsiveness. At presentation, her Glasgow Coma Scale was 11/15 (E4 V1M6). Notably, she had two strokelike episodes approximately 7 and 3 months prior to the current episode, with headache, reduced movement, and numbness in the left hand. She also had an extensive medical history at a young age, including congenital mydriasis, patent ductus arteriosus with ligation, dysautonomia, low blood pressure, hypotonic bladder requiring intermittent catheterization, poor bowel transit, and gallstones. Her immunization record was up to date, and her development was otherwise unremarkable. Her parents and younger sibling were healthy. Her blood tests revealed a mildly increased venous lactate level at 2.3 mmol/L (normal range, 0.7-2.1 mmol/L), without acidosis. Results of a coagulopathy work-up (clotting profile and protein C, protein S, antithrombin 3, and fibrinogen levels) were normal. MRI (Fig 1) and MR angiography of the brain (Fig 2) were performed at presentation.


Assuntos
Permeabilidade do Canal Arterial , Cálculos Biliares , Humanos , Feminino , Criança , Angiografia , Anticoagulantes , Encéfalo
11.
Biomed Pharmacother ; 164: 114935, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37245337

RESUMO

Asthma is a chronic inflammatory disease characterized by airway hypersensitivity and remodeling. The current treatments provide only short-term benefits and may have undesirable side effects; thus, alternative or supplementary therapy is needed. Because intracellular calcium (Ca2+) signaling plays an essential role in regulating the contractility and remodeling of airway smooth muscle cells, the targeting of Ca2+ signaling is a potential therapeutic strategy for asthma. Houttuynia cordata is a traditional Chinese herb that is used to treat asthma due to its anti-allergic and anti-inflammatory properties. We hypothesized that H. cordata might modulate intracellular Ca2+ signaling and could help relieve asthmatic airway remodeling. We found that the mRNA and protein levels of inositol trisphosphate receptors (IP3Rs) were elevated in interleukin-stimulated primary human bronchial smooth muscle cells and a house dust mite-sensitized model of asthma. The upregulation of IP3R expression enhanced intracellular Ca2+ release upon stimulation and contributed to airway remodeling in asthma. Intriguingly, pretreatment with H. cordata essential oil rectified the disruption of Ca2+ signaling, mitigated asthma development, and prevented airway narrowing. Furthermore, our analysis suggested that houttuynin/2-undecanone could be the bioactive component in H. cordata essential oil because we found similar IP3R suppression in response to the commercially available derivative sodium houttuyfonate. An in silico analysis showed that houttuynin, which downregulates IP3R expression, binds to the IP3 binding domain of IP3R and may mediate a direct inhibitory effect. In summary, our findings suggest that H. cordata is a potential alternative treatment choice that may reduce asthma severity by targeting the dysregulation of Ca2+ signaling.


Assuntos
Antiasmáticos , Asma , Houttuynia , Humanos , Sinalização do Cálcio , Houttuynia/metabolismo , Antiasmáticos/farmacologia , Antiasmáticos/uso terapêutico , Brônquios/metabolismo , Asma/tratamento farmacológico , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Cálcio/metabolismo
12.
Front Mol Biosci ; 9: 1030534, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387280

RESUMO

Emerging evidence from Alzheimer's disease (AD) patients suggests that reducing tau pathology can restore cognitive and memory loss. To reduce tau pathology, it is critical to find brain-permeable tau-degrading small molecules that are safe and effective. HDAC6 inhibition has long been considered a safe and effective therapy for tau pathology. Recently, we identified protopine as a dibenzazecine alkaloid with anti-HDAC6 and anti-AD activities. In this study, we synthesized and tested novel protopine derivatives for their pharmacological action against AD. Among them, bromo-protopine (PRO-Br) demonstrated a two-fold increase in anti-HDAC6 activity and improved anti-tau activities compared to the parent compound in both in vitro and in vivo AD models. Furthermore, molecular docking results showed that PRO-Br binds to HDAC6, with a ∆G value of -8.4 kcal/mol and an IC50 value of 1.51 µM. In neuronal cell lines, PRO-Br reduced pathological tau by inducing chaperone-mediated autophagy (CMA). In 3xTg-AD and P301S tau mice models, PRO-Br specifically decreased the pathogenic hyperphosphorylated tau clumps and led to the restoration of memory functions. In addition, PRO-Br treatment promoted the clearance of pathogenic tau by enhancing the expression of molecular chaperones (HSC70) and lysosomal markers (LAMP2A) via CMA in AD models. Our data strongly suggest that administration of the brain-permeable protopine derivative PRO-Br, could be a viable anti-tau therapeutic strategy for AD.

13.
J Biomed Sci ; 29(1): 85, 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273169

RESUMO

BACKGROUND: Tauopathies are neurodegenerative diseases that are associated with the pathological accumulation of tau-containing tangles in the brain. Tauopathy can impair cognitive and motor functions and has been observed in Alzheimer's disease (AD) and frontotemporal dementia (FTD). The aetiology of tauopathy remains mysterious; however, recent studies suggest that the autophagic-endolysosomal function plays an essential role in the degradation and transmission of pathological tau. We previously demonstrated that tetrandrine could ameliorate memory functions and clear amyloid plaques in transgenic AD mice by restoring autophagic-endolysosomal function. However, the efficacy of tetrandrine and the associated therapeutic mechanism in tauopathies have not been evaluated and elucidated. METHODS: Novel object recognition, fear conditioning and electrophysiology were used to evaluate the effects of tetrandrine on memory functions in transgenic tau mice. Western blotting and immunofluorescence staining were employed to determine the effect of tetrandrine on autophagy and tau clearance in vivo. Calcium (Ca2+) imaging and flow cytometry were used to delineate the role of pathological tau and tetrandrine in lysosomal Ca2+ and pH homeostasis. Biochemical BiFC fluorescence, Western blotting and immunofluorescence staining were used to evaluate degradation of hyperphosphorylated tau in vitro, whereas coculture of brain slices with isolated microglia was used to evaluate tau clearance ex vivo. RESULTS: We observed that tetrandrine treatment mitigated tau tangle development and corrected memory impairment in Thy1-hTau.P301S transgenic mice. Mechanistically, we showed that mutant tau expression disrupts lysosome pH by increasing two-pore channel 2 (TPC2)-mediated Ca2+ release, thereby contributing to lysosome alkalinization. Tetrandrine inhibits TPC2, thereby restoring the lysosomal pH, promotes tau degradation via autophagy, and ameliorates tau aggregation. Furthermore, in an ex vivo assay, we demonstrated that tetrandrine treatment promotes pathological tau clearance by microglia. CONCLUSIONS: Together, these findings suggest that pathological tau disturbs endolysosomal homeostasis to impair tau clearance. This impairment results in a vicious cycle that accelerates disease pathogenesis. The success of tetrandrine in reducing tau aggregation suggests first, that tetrandrine could be an effective drug for tauopathies and second, that rescuing lysosomal Ca2+ homeostasis, thereby restoring ALP function, could be an effective general strategy for the development of novel therapies for tauopathies.


Assuntos
Doença de Alzheimer , Tauopatias , Animais , Camundongos , Proteínas tau/genética , Cálcio , Modelos Animais de Doenças , Tauopatias/tratamento farmacológico , Tauopatias/patologia , Camundongos Transgênicos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Cognição
14.
Int J Mol Sci ; 23(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35408965

RESUMO

Eukaryotic cells possess a plethora of regulatory mechanisms to maintain homeostasis and ensure proper biochemical functionality. Autophagy, a central, conserved self-consuming process of the cell, ensures the timely degradation of damaged cellular components. Several studies have demonstrated the important roles of autophagy activation in mitigating neurodegenerative diseases, especially Alzheimer's disease (AD). However, surprisingly, activation of macroautophagy has not shown clinical efficacy. Hence, alternative strategies are urgently needed for AD therapy. In recent years, selective autophagy has been reported to be involved in AD pathology, and different subtypes have been identified, such as aggrephagy, mitophagy, reticulophagy, lipophagy, pexophagy, nucleophagy, lysophagy and ribophagy. By clarifying the underlying mechanisms governing these various subtypes, we may come to understand how to control autophagy to treat AD. In this review, we summarize the latest findings concerning the role of selective autophagy in the pathogenesis of AD. The evidence overwhelmingly suggests that selective autophagy is an active mechanism in AD pathology, and that regulating selective autophagy would be an effective strategy for controlling this pathogenesis.


Assuntos
Doença de Alzheimer , Macroautofagia , Doença de Alzheimer/patologia , Autofagia/fisiologia , Humanos , Mitofagia/fisiologia
15.
Redox Biol ; 51: 102280, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35286997

RESUMO

Accumulation of amyloid-ß (Aß) oligomers and phosphorylated Tau aggregates are crucial pathological events or factors that cause progressive neuronal loss, and cognitive impairments in Alzheimer's disease (AD). Current medications for AD have failed to halt, much less reverse this neurodegenerative disorder; therefore, there is an urgent need for the development of effective and safe drugs for AD therapy. In the present study, the in vivo therapeutic efficacy of an Aß-oligomer-targeted fluorescent probe, F-SLOH, was extensively investigated in 5XFAD and 3XTg-AD mouse models. We have shown that F-SLOH exhibits an efficient inhibitory activity against Aß aggregation in vivo, and acts as an effective theranostic agent for the treatment of multiple neuropathological changes in AD mouse models. F-SLOH has been found to significantly reduce not only the levels of Aß oligomers, Tau aggregates and plaques but also the levels of amyloid precursor protein (APP) and its metabolites via autophagy lysosomal degradation pathway (ALP) in the brains of 5XFAD and 3XTg-AD mice. It also reduces astrocyte activation and microgliosis ultimately alleviating neuro-inflammation. Furthermore, F-SLOH mitigates hyperphosphorylated Tau aggregates, synaptic deficits and ameliorates synaptic memory function, and cognitive impairment in AD mouse models. The mechanistic studies have shown that F-SLOH promotes the clearance of C-terminal fragment 15 (CTF15) of APP and Paired helical filaments of Tau (PHF1) in stable cell models via the activation of transcription factor EB (TFEB). Moreover, F-SLOH promotes ALP and lysosomal biogenesis for the clearance of soluble, insoluble Aß, and phospho Tau. Our results unambiguously reveal effective etiological capabilities of theranostic F-SLOH to target and intervene multiple neuropathological changes in AD mouse models. Therefore, F-SLOH demonstrates tremendous therapeutic potential for treating AD in its early stage.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Cognição , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Nanomedicina Teranóstica , Proteínas tau/metabolismo
16.
Acta Pharmacol Sin ; 43(10): 2511-2526, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35217810

RESUMO

Increasing evidence shows that autophagy impairment is involved in the pathogenesis and progression of neurodegenerative diseases including Parkinson's disease (PD). We previously identified a natural alkaloid named corynoxine B (Cory B) as a neuronal autophagy inducer. However, its brain permeability is relatively low, which hinders its potential use in treating PD. Thus we synthesized various derivatives of Cory B to find more potent autophagy inducers with improved brain bioavailability. In this study, we evaluated the autophagy-enhancing effect of CB6 derivative and its neuroprotective action against PD in vitro and in vivo. We showed that CB6 (5-40 µM) dose-dependently accelerated autophagy flux in cultured N2a neural cells through activating the PIK3C3 complex and promoting PI3P production. In MPP+-treated PC12 cells, CB6 inhibited cell apoptosis and increased cell viability by inducing autophagy. In MPTP-induced mouse model of PD, oral administration of CB6 (10, 20 mg· kg-1· d-1, for 21 days) significantly improved motor dysfunction and prevented the loss of dopaminergic neurons in the striatum and substantia nigra pars compacta. Collectively, compound CB6 is a brain-permeable autophagy enhancer via PIK3C3 complex activation, which may help the prevention or treatment of PD.


Assuntos
Alcaloides , Fármacos Neuroprotetores , Doença de Parkinson , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Alcaloides/farmacologia , Animais , Autofagia , Classe III de Fosfatidilinositol 3-Quinases/farmacologia , Neurônios Dopaminérgicos , Indóis , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/patologia , Ratos , Compostos de Espiro
17.
J Surg Educ ; 79(3): 655-660, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35123911

RESUMO

INTRODUCTION: To evaluate the operation time and surgical outcomes of elective laparoscopic cholecystectomy performed by surgical trainees at different levels of training at Eastern health and hence, to establish the efficacy and safety of elective laparoscopic cholecystectomy as an Entrustable Professional Activity for surgical trainees in general surgery. OBJECTIVE: Elective laparoscopic cholecystectomies performed at our institution between January 2018 and January 2019 were included. Analyses were divided among three groups - consultants (C), fellows (F) and registrars (R). Standard technique with critical view of safety was used. RESULTS: A total of 592 patients was included, with a mean age of 54 ± 63 years old. The average operation time was 84 ± 51 minutes. Surgical education and training (SET) 2 trainees took significantly longer when compared to their SET3 and above counterparts as a primary operator (SET2: 131 ± 32 min, Reference; SET3: 78 ± 21 min, p = 0.003; SET4: 80 ± 33 min, p = 0.004; SET5: 77 ± 28 min, p = 0.003; F: 93 ± 77 min, p = 0.036; C: 85 ± 59 min; p = 0.007). Consultant primary operators took an average of 15 minutes longer to complete the operation when assisted by a SET trainee compared to the non-SET registrars (p = 0.03). The overall complication rate was 3.2% and was not significantly different among all three groups (p = 0.17). No death was recorded during the study period. The readmission and return to theatre rates were 7.8% and 0.8% respectively and were not significantly different among the groups (p-values = 0.61 and 0.69). All conversion to open were performed by the consultant primary operator. CONCLUSIONS: Elective laparoscopic cholecystectomy can be safely performed by surgical trainees at all SET levels when under appropriate supervision, although junior surgical trainees that is SET 2 took longer to complete the procedure. This operation seems to have a steep, but relatively short, learning curve and it may be broken down into various components. These components, with the addition of time, may be suitable as an Entrustable Professional Activity tool for assessing the competency of early SET trainees.


Assuntos
Colecistectomia Laparoscópica , Idoso , Idoso de 80 Anos ou mais , Austrália , Colecistectomia Laparoscópica/educação , Consultores , Humanos , Curva de Aprendizado , Pessoa de Meia-Idade , Duração da Cirurgia
18.
Autophagy ; 18(3): 624-642, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34313551

RESUMO

ABBREVIATIONS: Aß: ß-amyloid; AD: Alzheimer disease; AIF1/IBA1: allograft inflammatory factor 1; ALP: autophagy-lysosomal pathway; APP: amyloid beta precursor protein; ATP6V1B1/V-ATPase V1b1: ATPase H+ transporting V1 subunit B1; AVs: autophagy vacuoles; BAF: bafilomycin A1; CFC: contextual/cued fear conditioning assay; CHX: Ca2+/H+ exchanger; CTF-ß: carboxy-terminal fragment derived from ß-secretase; CTSD: cathepsin D; fAD: familial Alzheimer disease; GFAP: glial fibrillary acidic protein; LAMP1: lysosomal associated membrane protein 1; LTP: long-term potentiation; MCOLN1/TRPML1: mucolipin 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAPT: microtubule associated protein tau; MWM: Morris water maze; NFT: neurofibrillary tangles; PFC: prefrontal cortex; PSEN1: presenilin 1; SQSTM1/p62: sequestosome 1; TBS: theta burst stimulation; TEM: transmission electronic microscopy; TPCN2/TPC2: two pore segment channel 2; WT: wild-type; V-ATPase: vacuolar type H+-ATPase.


Assuntos
Doença de Alzheimer , ATPases Vacuolares Próton-Translocadoras , Adenosina Trifosfatases/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Autofagia/fisiologia , Humanos , Lisossomos/metabolismo , Transtornos da Memória/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo
19.
Phytomedicine ; 96: 153887, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34936968

RESUMO

BACKGROUND: Collective evidences have indicated that intracellular accumulation of hyperphosphorylated tau forms neurofibrillary tangles in the brain, which impairs memory, cognition and affects social activities in Alzheimer's disease (AD). PURPOSE: To investigate the tau-reducing, and memory-enhancing properties of protopine (PRO), a natural alkaloid isolated from Chinese herbal medicine Corydalis yanhusuo (Yanhusuo in Chinese). STUDY DESIGN: By using Histone deacetylase 6 (HDAC6) profiling and immunoprecipitation assays, we assessed that PRO mediated the heat shock protein 90 (HSP90) chaperonic activities for the degradation of pathological tau in AD cell culture models. To study the efficacy of PRO in vivo, we employed 3xTg-AD and P301S tau mice models. METHODS: Liquid chromatography/quadrupole time-of-flight mass spectrometry was used to analyze the pharmacokinetic profile of PRO. Seven-month-old 3xTg-AD mice and 1.5-month-old P301S mice were administered PRO (1 and 2.5 mg/kg) orally every day. Morris water maze, contextual fear conditioning and rotarod assays were applied for studying memory functions. Sarkosyl differential centrifugation was used to analyze soluble and insoluble tau. Immunohistochemical analysis were performed to determine tau deposits in AD mice's brain sections. Molecular docking, binding affinity studies and primary cell culture studies were performed to demonstrate the mechanism of action of PRO in silico and in vitro. RESULTS: Our pharmacokinetic profiling demonstrated that PRO significantly entered the brain at a concentration of 289.47 ng/g, and specifically attenuated tau pathology, improved learning and memory functions in both 3xTg-AD and P301S mice. Docking, binding affinity studies, and fluorometric assays demonstrated that PRO directly bound to the catalytic domain 1 (CD1) of HDAC6 and down-regulated its activity. In primary cortical neurons, PRO enhanced acetylation of α-tubulin, indicating HDAC6 inhibition. Meanwhile, PRO promoted the ubiquitination of tau and recruited heat shock protein 70 (HSP70) and heat shock cognate complex 71 (HSC70) for the degradation of pathological tau via the ubiquitin-proteasomal system (UPS). CONCLUSION: We identified PRO as a natural HDAC6 inhibitor that attenuated tau pathology and improved memory dysfunctions in AD mice. The findings from this study provides a strong justification for future clinical development of plant-derived protopine as a novel agent for the treatment of tau-related neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Desacetilase 6 de Histona , Doença de Alzheimer/tratamento farmacológico , Animais , Benzofenantridinas , Alcaloides de Berberina , Modelos Animais de Doenças , Desacetilase 6 de Histona/antagonistas & inibidores , Camundongos , Camundongos Transgênicos , Simulação de Acoplamento Molecular , Proteínas tau
20.
Acta Pharmacol Sin ; 43(5): 1251-1263, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34417577

RESUMO

Transcriptional factor EB (TFEB), a master regulator of autophagy and lysosomal biogenesis, is generally regarded as a pro-survival factor. Here, we identify that besides its effect on autophagy induction, TFEB exerts a pro-apoptotic effect in response to the cyclopentenone prostaglandin 15-deoxy-∆-12,14-prostaglandin J2 (15d-PGJ2). Specifically, 15d-PGJ2 promotes TFEB translocation from the cytoplasm into the nucleus to induce autophagy and lysosome biogenesis via reactive oxygen species (ROS) production rather than mTORC1 inactivation. Surprisingly, TFEB promotes rather than inhibits apoptosis in response to 15d-PGJ2. Mechanistically, ROS-mediated TFEB translocation into the nucleus transcriptionally upregulates the expression of ATF4, which is required for apoptosis elicited by 15d-PGJ2. Additionally, inhibition of TFEB activation by ROS scavenger N-acetyl cysteine or inhibition of protein synthesis by cycloheximide effectively compromises ATF4 upregulation and apoptosis in response to 15d-PGJ2. Collectively, these results indicate that ROS-induced TFEB activation exerts a novel role in promoting apoptosis besides its role in regulating autophagy in response to 15d-PGJ2. This work not only evidences how TFEB is activated by 15d-PGJ2, but also unveils a previously unexplored role of ROS-dependent activation of TFEB in modulating cell apoptosis in response to 15d-PGJ2.


Assuntos
Prostaglandina D2 , Prostaglandinas , Apoptose , Autofagia , Ciclopentanos , Prostaglandina D2/análogos & derivados , Prostaglandina D2/farmacologia , Prostaglandinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
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