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1.
Nature ; 603(7901): 470-476, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236988

RESUMO

Alzheimer's disease has a higher incidence in older women, with a spike in cognitive decline that tracks with visceral adiposity, dysregulated energy homeostasis and bone loss during the menopausal transition1,2. Inhibiting the action of follicle-stimulating hormone (FSH) reduces body fat, enhances thermogenesis, increases bone mass and lowers serum cholesterol in mice3-7. Here we show that FSH acts directly on hippocampal and cortical neurons to accelerate amyloid-ß and Tau deposition and impair cognition in mice displaying features of Alzheimer's disease. Blocking FSH action in these mice abrogates the Alzheimer's disease-like phenotype by inhibiting the neuronal C/EBPß-δ-secretase pathway. These data not only suggest a causal role for rising serum FSH levels in the exaggerated Alzheimer's disease pathophysiology during menopause, but also reveal an opportunity for treating Alzheimer's disease, obesity, osteoporosis and dyslipidaemia with a single FSH-blocking agent.


Assuntos
Doença de Alzheimer , Hormônio Foliculoestimulante , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Densidade Óssea , Cognição , Feminino , Hormônio Foliculoestimulante/metabolismo , Humanos , Camundongos , Termogênese
2.
Mol Cell ; 67(5): 812-825.e5, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28826672

RESUMO

Delta-secretase, a lysosomal asparagine endopeptidase (AEP), simultaneously cleaves both APP and tau, controlling the onset of pathogenesis of Alzheimer's disease (AD). However, how this protease is post-translationally regulated remains unclear. Here we report that serine-arginine protein kinase 2 (SRPK2) phosphorylates delta-secretase and enhances its enzymatic activity. SRPK2 phosphorylates serine 226 on delta-secretase and accelerates its autocatalytic cleavage, leading to its cytoplasmic translocation and escalated enzymatic activities. Delta-secretase is highly phosphorylated in human AD brains, tightly correlated with SRPK2 activity. Overexpression of a phosphorylation mimetic (S226D) in young 3xTg mice strongly promotes APP and tau fragmentation and facilitates amyloid plaque deposits and neurofibrillary tangle (NFT) formation, resulting in cognitive impairment. Conversely, viral injection of the non-phosphorylatable mutant (S226A) into 5XFAD mice decreases APP and tau proteolytic cleavage, attenuates AD pathologies, and reverses cognitive defects. Our findings support that delta-secretase phosphorylation by SRPK2 plays a critical role in aggravating AD pathogenesis.


Assuntos
Doença de Alzheimer/enzimologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Encéfalo/enzimologia , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Secretases da Proteína Precursora do Amiloide/genética , Animais , Comportamento Animal , Encéfalo/patologia , Encéfalo/fisiopatologia , Cognição , Modelos Animais de Doenças , Predisposição Genética para Doença , Células HEK293 , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Fenótipo , Fosforilação , Placa Amiloide , Proteínas Serina-Treonina Quinases/genética , Transporte Proteico , Interferência de RNA , Serina , Especificidade por Substrato , Fatores de Tempo , Transfecção , Proteínas tau/genética , Proteínas tau/metabolismo
3.
World J Surg Oncol ; 22(1): 230, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232702

RESUMO

BACKGROUND: Totally robotic distal gastrectomy (TRDG) is being used more and more in gastric cancer (GC) patients. The study aims to evaluate the short-term efficacy of TRDG and robotic-assisted distal gastrectomy (RADG) in the treatment of GC. METHODS: We retrospectively collected the clinical data of patients who underwent TRDG or RADG, of which 60 patients were included in the study: 30 cases of totally robotic and 30 cases of robotic-assisted. The short-term efficacy of the two groups was compared. RESULTS: There was no significant difference in the clinicopathological data between the two groups. Compared to RADG, TRDG had less intraoperative blood loss(P = 0.019), less postoperative abdominal drainage(P = 0.031), shorter time of exhaust( P = 0.001) and liquid diet(P = 0.001), shorter length of incision(P<0.01), shorter postoperative hospital stays(P = 0.033), lower postoperative C-reactive protein(CRP)(P = 0.024) and lower postoperative Visual Analogue Scale(VAS) scores(P = 0.048). However, no significant statistical differences were found in terms of total operation time(P = 0.108), number of lymph nodes retrieved(P = 0.307), time for anastomosis(P = 0.450), proximal resection margin(P = 0.210), distal resection margin(P = 0.202), postoperative complication(P = 0.506), total hospital cost(P = 0.286) and postoperative white blood cell(WBC)(P = 0.113). CONCLUSIONS: In terms of security and technology, TRDG could serve as a better treatment method for GC.


Assuntos
Gastrectomia , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Gastrectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/economia , Procedimentos Cirúrgicos Robóticos/estatística & dados numéricos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Seguimentos , Prognóstico , Idoso , Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Duração da Cirurgia , Resultado do Tratamento , Adulto
4.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34140411

RESUMO

The molecular mechanism of Alzheimer's disease (AD) pathogenesis remains obscure. Life and/or environmental events, such as traumatic brain injury (TBI), high-fat diet (HFD), and chronic cerebral hypoperfusion (CCH), are proposed exogenous risk factors for AD. BDNF/TrkB, an essential neurotrophic signaling for synaptic plasticity and neuronal survival, are reduced in the aged brain and in AD patients. Here, we show that environmental factors activate C/EBPß, an inflammatory transcription factor, which subsequently up-regulates δ-secretase that simultaneously cleaves both APP and Tau, triggering AD neuropathological changes. These adverse effects are additively exacerbated in BDNF+/- or TrkB+/- mice. Strikingly, TBI provokes both senile plaque deposit and neurofibrillary tangles (NFT) formation in TrkB+/- mice, associated with augmented neuroinflammation and extensive neuronal loss, leading to cognitive deficits. Depletion of C/EBPß inhibits TBI-induced AD-like pathologies in these mice. Remarkably, amyloid aggregates and NFT are tempospatially distributed in TrkB+/- mice brains after TBI, providing insight into their spreading in the progression of AD-like pathologies. Hence, our study revealed the roles of exogenous (TBI, HFD, and CCH) and endogenous (TrkB/BDNF) risk factors in the onset of AD-associated pathologies.


Assuntos
Doença de Alzheimer/metabolismo , Progressão da Doença , Meio Ambiente , Fatores de Crescimento Neural/metabolismo , Transdução de Sinais , Envelhecimento/metabolismo , Doença de Alzheimer/complicações , Amiloide/metabolismo , Animais , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/patologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Disfunção Cognitiva/complicações , Disfunção Cognitiva/patologia , Cisteína Endopeptidases/metabolismo , Dieta Hiperlipídica , Humanos , Camundongos Endogâmicos C57BL , Emaranhados Neurofibrilares/patologia , Placa Amiloide/patologia , Receptor trkB/metabolismo , Fatores de Risco
5.
Mol Psychiatry ; 27(7): 3034-3046, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35422468

RESUMO

Atherosclerosis (ATH) and Alzheimer's disease (AD) are both age-dependent inflammatory diseases, associated with infiltrated macrophages and vascular pathology and overlapping molecules. C/EBPß, an Aß or inflammatory cytokine-activated transcription factor, and AEP (asparagine endopeptidase) are intimately implicated in both ATH and AD; however, whether C/EBPß/AEP signaling couples ATH to AD pathogenesis remains incompletely understood. Here we show that C/EBPß/AEP pathway mediates ATH pathology and couples ATH to AD. Deletion of C/EBPß or AEP from primary macrophages diminishes cholesterol load, and inactivation of this pathway reduces foam cell formation and lesions in aorta in ApoE-/- mice, fed with HFD (high-fat-diet). Knockout of ApoE from 3xTg AD mouse model augments serum LDL and increases lesion areas in the aorta. Depletion of C/EBPß or AEP from 3xTg/ApoE-/- mice substantially attenuates these effects and elevates cerebral blood flow and vessel length, improving cognitive functions. Strikingly, knockdown of ApoE from the hippocampus of 3xTg mice decreases the cerebral blood flow and vessel length and aggravates AD pathologies, leading to cognitive deficits. Inactivation of C/EBPß/AEP pathway alleviates these events and restores cognitive functions. Hence, our findings demonstrate that C/EBPß/AEP signaling couples ATH to AD via mediating vascular pathology.


Assuntos
Doença de Alzheimer , Aterosclerose , Proteína beta Intensificadora de Ligação a CCAAT , Doença de Alzheimer/metabolismo , Animais , Aterosclerose/complicações , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Knockout para ApoE
6.
Mol Psychiatry ; 27(6): 2901-2913, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35318460

RESUMO

The central nervous system has evolved to coordinate the regulation of both the behavior response to the external environment and homeostasis of energy expenditure. Recent studies have indicated the dorsomedial ventromedial hypothalamus (dmVMH) as an important hub that regulates both innate behavior and energy homeostasis for coping stress. However, how dmVMH neurons control neuronal firing pattern to regulate chronic stress-induced anxiety and energy expenditure remains poorly understood. Here, we found enhanced neuronal activity in VMH after chronic stress, which is mainly induced by increased proportion of burst firing neurons. This enhancement of VMH burst firing is predominantly mediated by Cav3.1 expression. Optogenetically evoked burst firing of dmVMH neurons induced anxiety-like behavior, shifted the respiratory exchange ratio toward fat oxidation, and decreased food intake, while knockdown of Cav3.1 in the dmVMH had the opposite effects, suggested that Cav 3.1 as a crucial regulator. Interestingly, we found that fluoxetine (anxiolytics) could block the increase of Cav3.1 expression to inhibit the burst firing, and then rescued the anxiety-like behaviors and energy expenditure changes. Collectively, our study first revealed an important role of Cav3.1-driven bursting firing of dmVMH neurons in the control of anxiety-like behavior and energy expenditure, and provided potential therapeutic targets for treating the chronic stress-induced emotional malfunction and metabolism disorders.


Assuntos
Hipotálamo , Neurônios , Ansiedade , Metabolismo Energético , Neurônios/metabolismo
7.
World J Surg Oncol ; 21(1): 196, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403084

RESUMO

BACKGROUND: Surgery is becoming less invasive as technology advances. Natural orifice specimen extraction surgery (NOSES) ushered in a new era of minimally invasive techniques. At the same time, NOSES is gaining popularity in the world. With their distinct advantages, surgical robots have advanced the development of NOSES. The aim of current study was to compare the short-term outcomes between robotic-assisted NOSES and laparoscopic-assisted NOSES for the treatment of middle rectal cancer. METHODS: Patients with middle rectal cancer who underwent robotic-assisted or laparoscopic-assisted NOSES at the First Affiliated Hospital of Nanchang University between January 2020 and June 2022 had their clinicopathological data collected retrospectively. 46 patients were enrolled in the study: 23 in the robotic group and 23 in the laparoscopic group. Short-term outcomes and postoperative anal function in the two groups were compared. RESULTS: There was no significant difference in the clinicopathological data between the two groups. The robotic group had less intraoperative blood loss (p = 0.04), less postoperative abdominal drainage (p = 0.02), lower postoperative white blood cell counts (p = 0.024) and C-reactive protein levels (p = 0.017), and shorter catheter removal time when compared to the laparoscopic group (p = 0.003). Furthermore, there were no significant difference in mean operative time (159 ± 31 min vs 172 ± 41 min) between the robotic and laparoscopic groups (p = 0.235), but time to naked the rectum (86.4 ± 20.9 min vs. 103.8 ± 31.5 min p = 0.033) and time of digestive tract reconstruction (15.6 ± 3.88 min vs. 22.1 ± 2.81 min p < 0.01) in the robotic group were significantly shorter than laparoscopic group. The robotic group had lower postoperative Wexner scores than the laparoscopic group. CONCLUSIONS: This research reveals that combining a robotic surgical system and NOSES results in superior outcomes, with short-term outcomes preferable to laparoscopic-assisted NOSES.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Laparoscopia/métodos , Neoplasias Retais/cirurgia
8.
Neurodegener Dis ; 23(1-2): 1-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37666228

RESUMO

BACKGROUND: Although Alzheimer's disease (AD) is the most common form of dementia, the effective treatment of AD is not available currently. Multiple trials of drugs, which were developed based on the amyloid hypothesis of AD, have not been highly successful to improve cognitive and other symptoms in AD patients, suggesting that it is necessary to explore additional and alternative approaches for the disease-modifying treatment of AD. The diverse lines of evidence have revealed that lithium reduces amyloid and tau pathology, attenuates neuronal loss, enhances synaptic plasticity, and improves cognitive function. Clinical studies have shown that lithium reduces the risk of AD and deters the progress of mild cognitive impairment and early AD. SUMMARY: Our recent study has revealed that lithium stabilizes disruptive calcium homeostasis, and subsequently, attenuates the downstream neuropathogenic processes of AD. Through these therapeutic actions, lithium produces therapeutic effects on AD with potential to modify the disease process. This review critically analyzed the preclinical and clinical studies for the therapeutic effects of lithium on AD. We suggest that disruptive calcium homeostasis is likely to be the early neuropathological mechanism of AD, and the stabilization of disruptive calcium homeostasis by lithium would be associated with its therapeutic effects on neuropathology and cognitive deficits in AD. KEY MESSAGES: Lithium is likely to be efficacious for AD as a disease-modifying drug by acting on multiple neuropathological targets including disruptive calcium homeostasis.


Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Humanos , Doença de Alzheimer/patologia , Lítio/uso terapêutico , Cálcio , Peptídeos beta-Amiloides
9.
BMC Surg ; 23(1): 336, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940918

RESUMO

BACKGROUND: With the development of minimally invasive technology, the trauma caused by surgery get smaller, At the same time, the specimen extraction surgery through the natural orifice is more favored by experts domestically and abroad, robotic surgery has further promoted the development of specimen extraction surgery through the natural orifice. The aim of current study is to compare the short-term outcomes of robotic-assisted natural orifice specimen extraction (NOSES ) and transabdominal specimen extraction(TRSE ) in median rectal cancer surgery. METHODS: From January 2020 to January 2023, 87 patients who underwent the NOSES or TRSE at the First Affiliated Hospital of Nanchang University were included in the study, 4 patients were excluded due to liver metastasis. Of these, 50 patients were in the TRSE and 33 patients in the NOSES. Short-term efficacy was compared in the two groups. RESULTS: The NOSES group had less operation time (P < 0.001), faster recovery of gastrointestinal function (P < 0.001), shorter abdominal incisions (P < 0.001), lower pain scores(P < 0.001). lower Inflammatory indicators of the white blood cell count and C-reactive protein content at 1, 3, and 5 days after surgery (P < 0.001, P = 0.037). There were 9 complications in the NOSES group and 11 complications in the TRSE group(P = 0.583). However, there were no wound complications in the NOSES group. The number of postoperative hospital stays seems to be same in the two groups. And there was no significant difference in postoperative anus function (P = 0.591). CONCLUSIONS: This study shows that NOSES and TRSE can achieve similar radical treatment effects, NOSES is a feasible and safe way to take specimens for rectal cancer surgery in accordance with the indication for NOSES.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Estudos Retrospectivos , Neoplasias Retais/cirurgia , Reto , Resultado do Tratamento
10.
Alzheimers Dement ; 19(9): 4267-4269, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37485581

RESUMO

Our recent investigation revealed that deficiency of N-methyl-D-aspartate (NMDA) receptor subunit GluN3A (NR3A) is a trigger for chronic neuronal hyperactivity and disruptionFfepspof Ca2+ homeostasis, leading to sporadic Alzheimer's disease (AD) phenotypes. The identification of the amyloid-independent pathogenesis was a surprise considering that GluN3A is a much less known NMDA receptor subunit with obscure function in aging adulthood, while the new concept of degenerative excitotoxicity as a decade-long pathogenic mechanism of AD/dementia remains to be further delineated. With negative observations in GRIN3A-/- mouse, Verhaeghe et al. in their letter challenge the "odd" idea that lasting GluN3A deficiency is detrimental and responsible for the spontaneous progression of AD and cognitive decline. We now discuss the potential mouse strain hypothesis and experimental data in these two investigations, and provide additional evidence that further supports the validity and specificity of GluN3A deficiency in the development of AD and associated dementia.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/genética , Neurônios , Receptores de N-Metil-D-Aspartato/genética
11.
Mol Psychiatry ; 26(10): 6002-6022, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33339957

RESUMO

The apolipoprotein E ε4 (APOE4) allele is a major genetic risk factor for Alzheimer's disease (AD), and its protein product, ApoE4, exerts its deleterious effects mainly by influencing amyloid-ß (Aß) and Tau (neurofibrillary tangles, NFTs) deposition in the brain. However, the molecular mechanism dictating its expression during ageing and in AD remains incompletely clear. Here we show that C/EBPß acts as a pivotal transcription factor for APOE and mediates its mRNA levels in an age-dependent manner. C/EBPß binds the promoter of APOE and escalates its expression in the brain. Knockout of C/EBPß in AD mouse models diminishes ApoE expression and Aß pathologies, whereas overexpression of C/EBPß accelerates AD pathologies, which can be attenuated by anti-ApoE monoclonal antibody or deletion of ApoE via its specific shRNA. Remarkably, C/EBPß selectively promotes more ApoE4 expression versus ApoE3 in human neurons, correlating with higher activation of C/EBPß in human AD brains with ApoE4/4 compared to ApoE3/3. Therefore, our data support that C/EBPß is a crucial transcription factor for temporally regulating APOE gene expression, modulating ApoE4's role in AD pathogenesis.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Apolipoproteína E4/genética , Apolipoproteínas E , Encéfalo/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Camundongos , Camundongos Knockout
12.
Mol Psychiatry ; 26(2): 586-603, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-30382187

RESUMO

δ-Secretase, an age-dependent asparagine protease, cleaves both amyloid precursor protein (APP) and Tau and is required for amyloid plaque and neurofibrillary tangle pathologies in Alzheimer's disease (AD). However, whether δ-secretase activation is sufficient to trigger AD pathogenesis remains unknown. Here we show that the fragments of δ-secretase-cleavage, APP (586-695) and Tau(1-368), additively drive AD pathogenesis and cognitive dysfunctions. Tau(1-368) strongly augments BACE1 expression and Aß generation in the presence of APP. The Tau(1-368) fragment is more robust than full-length Tau in binding active STAT1, a BACE1 transcription factor, and promotes its nuclear translocation, upregulating BACE1 and Aß production. Notably, Aß-activated SGK1 or JAK2 kinase phosphorylates STAT1 and induces its association with Tau(1-368). Inhibition of these kinases diminishes stimulatory effect of Tau(1-368). Knockout of STAT1 abolishes AD pathologies induced by δ-secretase-generated APP and Tau fragments. Thus, we show that Tau may not only be a downstream effector of Aß in the amyloid hypothesis, but also act as a driving force for Aß, when cleaved by δ-secretase.


Assuntos
Doença de Alzheimer , Secretases da Proteína Precursora do Amiloide , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Humanos , Emaranhados Neurofibrilares , Fator de Transcrição STAT1 , Proteínas tau/metabolismo
13.
Proc Natl Acad Sci U S A ; 116(18): 9094-9102, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31004063

RESUMO

BDNF, an essential trophic factor implicated in synaptic plasticity and neuronal survival, is reduced in Alzheimer's disease (AD). BDNF deficiency's association with Tau pathology in AD is well documented. However, the molecular mechanisms accounting for these events remain incompletely understood. Here we show that BDNF deprivation triggers Tau proteolytic cleavage by activating δ-secretase [i.e., asparagine endopeptidase (AEP)], and the resultant Tau N368 fragment binds TrkB receptors and blocks its neurotrophic signals, inducing neuronal cell death. Knockout of BDNF or TrkB receptors provokes δ-secretase activation via reducing T322 phosphorylation by Akt and subsequent Tau N368 cleavage, inducing AD-like pathology and cognitive dysfunction, which can be restored by expression of uncleavable Tau N255A/N368A mutant. Blocking the Tau N368-TrkB complex using Tau repeat-domain 1 peptide reverses this pathology. Thus, our findings support that BDNF reduction mediates Tau pathology via activating δ-secretase in AD.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Receptor trkB/antagonistas & inibidores , Proteínas tau/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Linhagem Celular , Cognição/fisiologia , Disfunção Cognitiva/metabolismo , Cisteína Endopeptidases/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Emaranhados Neurofibrilares/metabolismo , Neurônios/metabolismo , Fosforilação , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor trkB/metabolismo , Transdução de Sinais
14.
Alzheimers Dement ; 18(2): 222-239, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34151525

RESUMO

The Ca2+ hypothesis for Alzheimer's disease (AD) conceives Ca2+ dyshomeostasis as a common mechanism of AD; the cause of Ca2+ dysregulation, however, is obscure. Meanwhile, hyperactivities of N-Methyl-D-aspartate receptors (NMDARs), the primary mediator of Ca2+ influx, are reported in AD. GluN3A (NR3A) is an NMDAR inhibitory subunit. We hypothesize that GluN3A is critical for sustained Ca2+ homeostasis and its deficiency is pathogenic for AD. Cellular, molecular, and functional changes were examined in adult/aging GluN3A knockout (KO) mice. The GluN3A KO mouse brain displayed age-dependent moderate but persistent neuronal hyperactivity, elevated intracellular Ca2+ , neuroinflammation, impaired synaptic integrity/plasticity, and neuronal loss. GluN3A KO mice developed olfactory dysfunction followed by psychological/cognitive deficits prior to amyloid-ß/tau pathology. Memantine at preclinical stage prevented/attenuated AD syndromes. AD patients' brains show reduced GluN3A expression. We propose that chronic "degenerative excitotoxicity" leads to sporadic AD, while GluN3A represents a primary pathogenic factor, an early biomarker, and an amyloid-independent therapeutic target.


Assuntos
Doença de Alzheimer , Receptores de N-Metil-D-Aspartato , Doença de Alzheimer/metabolismo , Animais , Humanos , Memantina/farmacologia , Memantina/uso terapêutico , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/genética
15.
Neurochem Res ; 46(4): 732-739, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33521906

RESUMO

Erythropoietin (EPO) is an exciting neurotherapeutic option. Despite its potential, concerns exist regarding the potential for thrombosis and adverse events with EPO administration in normonemic adults. Systematic review of literature using PRISMA guidelines to examine the application and risks of EPO as a treatment option for neuroprotection in normonemic adults. Independent, systematic searches were performed in July 2019. PubMed (1960-2019) and the Cochrane Controlled Trials Register (1960-2019) were screened. Search terms included erythropoietin, neuroprotection, and humans. The PubMed search resulted in the following search strategy: ("erythropoietin" [MeSH Terms] OR "erythropoietin" [All Fields] OR "epoetin alfa" [MeSH Terms] OR ("epoetin" [All Fields] AND "alfa" [All Fields]) OR "epoetin alfa" [All Fields]) AND ("neuroprotection" [MeSH Terms] OR "neuroprotection" [All Fields]) AND "humans" [MeSH Terms]. PubMed, Cochrane Controlled Trials Register, and articles based on prior searches yielded 388 citations. 50 studies were included, comprising of 4351 patients. There were 13 studies that noted adverse effects from EPO. Three attributed serious adverse effects to EPO and complications were statistically significant. Two of these studies related the adverse events to the co-administration of EPO with tPA. Minor adverse effects associated with the EPO group included nausea, pyrexia, headache, generalized weakness and superficial phlebitis. Most published studies focus on spinal cord injury, peri-surgical outcomes and central effects of EPO. We found no studies to date evaluating the role of EPO in post-operative pain. Future trials could evaluate this application in persistent post-surgical pain and in the peri-operative period.


Assuntos
Eritropoetina/uso terapêutico , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Doenças do Sistema Nervoso Central/tratamento farmacológico , Eritropoetina/efeitos adversos , Humanos , Fármacos Neuroprotetores/efeitos adversos , Neurite Óptica/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/tratamento farmacológico
16.
Luminescence ; 36(1): 66-72, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32706457

RESUMO

Tuberculosis is one of the main infectious diseases threatening public health, and the development of simple, rapid, and cost-saving methods for tuberculosis diagnosis is of profound importance for tuberculosis prevention and treatment. The bacterium Mycobacterium tuberculosis (MTB) is the pathogen that causes tuberculosis, and assaying for MTB is the only criterion for tuberculosis diagnosis. A new enzyme-free method based on strand displacement amplification and magnetic beads was developed for simple, rapid, and cost-saving MTB detection. Under optimum conditions, a good linear relationship could be observed between fluorescence and MTB specific DNA concentration ranging from 0.05 to 150 nM with a correlation coefficient of 0.993 (n = 8) and a detection limit of 47 pM (3σ/K). The present method also distinguished a one base mismatch from MTB specific DNA, showing great promise for MTB genome single base polymorphism analysis. MTB specific DNA content in polymerase chain reaction samples was successfully detected using the new method, and recoveries were 97.8-100.8%, indicating that the present method had high accuracy and shows good potential for the early diagnosis of tuberculosis.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Fenômenos Magnéticos , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
17.
J Neurosci ; 39(33): 6571-6594, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31263065

RESUMO

Cell transplantation therapy provides a regenerative strategy for neural repair. We tested the hypothesis that selective excitation of transplanted induced pluripotent stem cell-derived neural progenitor cells (iPS-NPCs) could recapitulate an activity-enriched microenvironment that confers regenerative benefits for the treatment of stroke. Mouse iPS-NPCs were transduced with a novel optochemogenetics fusion protein, luminopsin 3 (LMO3), which consisted of a bioluminescent luciferase, Gaussia luciferase, and an opsin, Volvox Channelrhodopsin 1. These LMO3-iPS-NPCs can be activated by either photostimulation using light or by the luciferase substrate coelenterazine (CTZ). In vitro stimulations of LMO3-iPS-NPCs increased expression of synapsin-1, postsynaptic density 95, brain derived neurotrophic factor (BDNF), and stromal cell-derived factor 1 and promoted neurite outgrowth. After transplantation into the ischemic cortex of mice, LMO3-iPS-NPCs differentiated into mature neurons. Synapse formation between implanted and host neurons was identified using immunogold electron microscopy and patch-clamp recordings. Stimulation of transplanted cells with daily intranasal administration of CTZ enhanced axonal myelination, synaptic transmission, improved thalamocortical connectivity, and functional recovery. Patch-clamp and multielectrode array recordings in brain slices showed that CTZ or light stimulation facilitated synaptic transmission and induced neuroplasticity mimicking the LTP of EPSPs. Stroke mice received the combined LMO3-iPS-NPC/CTZ treatment, but not cell or CTZ alone, showed enhanced neural network connections in the peri-infarct region, promoted optimal functional recoveries after stroke in male and female, young and aged mice. Thus, excitation of transplanted cells via the noninvasive optochemogenetics treatment provides a novel integrative cell therapy with comprehensive regenerative benefits after stroke.SIGNIFICANCE STATEMENT Neural network reconnection is critical for repairing damaged brain. Strategies that promote this repair are expected to improve functional outcomes. This study pioneers the generation and application of an optochemogenetics approach in stem cell transplantation therapy after stroke for optimal neural repair and functional recovery. Using induced pluripotent stem cell-derived neural progenitor cells (iPS-NPCs) expressing the novel optochemogenetic probe luminopsin (LMO3), and intranasally delivered luciferase substrate coelenterazine, we show enhanced regenerative properties of LMO3-iPS-NPCs in vitro and after transplantation into the ischemic brain of different genders and ages. The noninvasive repeated coelenterazine stimulation of transplanted cells is feasible for clinical applications. The synergetic effects of the combinatorial cell therapy may have significant impacts on regenerative approach for treatments of CNS injuries.


Assuntos
Células-Tronco Neurais/transplante , Optogenética/métodos , Recuperação de Função Fisiológica , Transplante de Células-Tronco/métodos , Acidente Vascular Cerebral , Animais , Diferenciação Celular/fisiologia , Feminino , Células-Tronco Pluripotentes Induzidas/transplante , Masculino , Camundongos , Remielinização/fisiologia , Transmissão Sináptica/fisiologia
18.
J Neurosci Res ; 98(3): 481-490, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31670406

RESUMO

Luminopsins (LMOs) are chimeric proteins consisting of a luciferase fused to an opsin that provide control of neuronal activity, allowing for less cumbersome and less invasive optogenetic manipulation. It was previously shown that both an external light source and the luciferase substrate, coelenterazine (CTZ), could modulate activity of LMO-expressing neurons, although the magnitudes of the photoresponses remained subpar. In this study, we created an enhanced iteration of the excitatory luminopsin LMO3, termed eLMO3, that has improved membrane targeting due to the insertion of a Golgi trafficking signal sequence. In cortical neurons in culture, the expression of eLMO3 resulted in significant reductions in the formation of intracellular aggregates, as well as in a significant increase in total photocurrents. Furthermore, we corroborated the findings with injections of adeno-associated viral vectors into the deep layers of the somatosensory cortex (the barrel cortex) of male mice. We observed greatly reduced numbers of intracellular puncta in eLMO3-expressing cortical neurons compared to those expressing the original LMO3. Finally, we quantified CTZ-driven behavior, namely whisker-touching behavior, in male mice with LMO3 expression in the barrel cortex. After CTZ administration, mice with eLMO3 displayed significantly longer whisker responses than mice with LMO3. In summary, we have engineered the superior LMO by resolving membrane trafficking defects, and we demonstrated improved membrane targeting, greater photocurrents, and greater functional responses to stimulate with CTZ.


Assuntos
Imidazóis/administração & dosagem , Luciferases/metabolismo , Substâncias Luminescentes/administração & dosagem , Neurônios/metabolismo , Opsinas/metabolismo , Optogenética/métodos , Transporte Proteico , Pirazinas/administração & dosagem , Córtex Somatossensorial/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Feminino , Medições Luminescentes , Masculino , Potenciais da Membrana , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Cultura Primária de Células , Córtex Somatossensorial/efeitos dos fármacos
19.
Opt Express ; 28(1): 676-684, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118990

RESUMO

A novel combined laser pulses (CLPs) consisting of a millisecond (ms) pulse and an assisted nanosecond (ns) pulse train was proposed for drilling alumina ceramic. The processing efficiency and quality were well improved by spatially and temporally superposing the ms and ns laser beams. As a result, due to the multi-reflection of keyhole and ejection of melt, the temporally superposed CLPs could decrease the energy consumption of the drilling by an order of magnitude compared with the conventional ms pulse. On the other hand, the spatial distribution of the ns laser on the focal plane was elliptical due to the off-axis distortion of the optical system. However, since the reflection of the laser in the keyhole was non-uniform, the spatially superposed CLPs showed no dependence on the shape of the focused elliptical ns laser spot in terms of the drilling quality. The research results have an important guiding for improving the efficiency and quality of laser processing, especially for the alumina ceramic laser processing.

20.
BMC Pregnancy Childbirth ; 20(1): 654, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33121473

RESUMO

BACKGROUND: Ectopic pregnancy is a major life- and fertility-threatening women's health concern. As a result of advances in examination technology, an increasing number of ectopic pregnancies can be diagnosed early and treated with medical methods instead of surgery. The aim of this study was to summarize the clinical features and identify the predictors of success of methotrexate (MTX) treatment of ectopic pregnancy. METHODS: This was a retrospective study of 238 ectopic pregnancies treated with MTX in the Department of Gynecology of Shaanxi Provincial People's Hospital from January 2017 to December 2017. RESULTS: Patients were divided into two groups: the successful treatment group (n = 166) and the failed treatment group (n = 72). The overall success rate of MTX therapy for ectopic pregnancy was 69.75%. The mean initial beta-human chorionic gonadotropin (ß-hCG) level was significantly lower in the successful treatment group than in the failed treatment group (2538.08 IU/L versus 3533.17 IU/L, P = 0.000). The treatment success rate of the group with an initial ß-hCG concentration less than 4000 IU/L was significantly higher than that of the group with an initial ß-hCG concentration greater than 4000 IU/L. However, the success rate of the group with an initial ß-hCG concentration greater than 4000 IU/L was still relatively high (54.55%). ß-hCG levels were significantly increased on the 4th day in the failed treatment group (P = 0.000). Compared to the initial ß-hCG level, the day-4 ß-hCG level increased by more than 8.21%, indicating that the treatment was effective. The diagnostic sensitivity was 88.6%, the specificity was 74.5%, and the area under the receiver operating characteristic (ROC) curve was 0.863 (95% confidence interval (CI): 0.805-0.920). CONCLUSIONS: MTX therapy as a treatment option is safe and effective for asymptomatic, hemodynamically stable patients with ectopic pregnancies who are interested in conservative treatment, regardless of the serum ß-hCG level or adnexal mass size. The change in the ß-hCG level between the initial day and the 4th day is an effective and early predictive tool for the success of MTX therapy for ectopic pregnancy.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Tratamento Conservador/métodos , Monitoramento de Medicamentos/métodos , Metotrexato/administração & dosagem , Gravidez Ectópica/tratamento farmacológico , Adulto , Doenças Assintomáticas/terapia , Feminino , Humanos , Metotrexato/efeitos adversos , Gravidez , Gravidez Ectópica/sangue , Gravidez Ectópica/diagnóstico , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento , Adulto Jovem
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