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1.
Circ Res ; 134(7): e17-e33, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420756

RESUMO

BACKGROUND: Microvascular complications are the major outcome of type 2 diabetes progression, and the underlying mechanism remains to be determined. METHODS: High-throughput RNA sequencing was performed using human monocyte samples from controls and diabetes. The transgenic mice expressing human CTSD (cathepsin D) in the monocytes was constructed using CD68 promoter. In vivo 2-photon imaging, behavioral tests, immunofluorescence, transmission electron microscopy, Western blot analysis, vascular leakage assay, and single-cell RNA sequencing were performed to clarify the phenotype and elucidate the molecular mechanism. RESULTS: Monocytes expressed high-level CTSD in patients with type 2 diabetes. The transgenic mice expressing human CTSD in the monocytes showed increased brain microvascular permeability resembling the diabetic microvascular phenotype, accompanied by cognitive deficit. Mechanistically, the monocytes release nonenzymatic pro-CTSD to upregulate caveolin expression in brain endothelium triggering caveolae-mediated transcytosis, without affecting the paracellular route of brain microvasculature. The circulating pro-CTSD activated the caveolae-mediated transcytosis in brain endothelial cells via its binding with low-density LRP1 (lipoprotein receptor-related protein 1). Importantly, genetic ablation of CTSD in the monocytes exhibited a protective effect against the diabetes-enhanced brain microvascular transcytosis and the diabetes-induced cognitive impairment. CONCLUSIONS: These findings uncover the novel role of circulatory pro-CTSD from monocytes in the pathogenesis of cerebral microvascular lesions in diabetes. The circulatory pro-CTSD is a potential target for the intervention of microvascular complications in diabetes.


Assuntos
Catepsina D , Diabetes Mellitus Tipo 2 , Monócitos , Animais , Humanos , Camundongos , Encéfalo/metabolismo , Catepsina D/metabolismo , Catepsina D/farmacologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Precursores Enzimáticos , Camundongos Transgênicos , Monócitos/metabolismo , Transcitose/fisiologia
2.
J Neuroinflammation ; 21(1): 125, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730470

RESUMO

BACKGROUND: Understanding the molecular mechanisms of Alzheimer's disease (AD) has important clinical implications for guiding therapy. Impaired amyloid beta (Aß) clearance is critical in the pathogenesis of sporadic AD, and blood monocytes play an important role in Aß clearance in the periphery. However, the mechanism underlying the defective phagocytosis of Aß by monocytes in AD remains unclear. METHODS: Initially, we collected whole blood samples from sporadic AD patients and isolated the monocytes for RNA sequencing analysis. By establishing APP/PS1 transgenic model mice with monocyte-specific cystatin F overexpression, we assessed the influence of monocyte-derived cystatin F on AD development. We further used a nondenaturing gel to identify the structure of the secreted cystatin F in plasma. Flow cytometry, enzyme-linked immunosorbent assays and laser scanning confocal microscopy were used to analyse the internalization of Aß by monocytes. Pull down assays, bimolecular fluorescence complementation assays and total internal reflection fluorescence microscopy were used to determine the interactions and potential interactional amino acids between the cystatin F protein and Aß. Finally, the cystatin F protein was purified and injected via the tail vein into 5XFAD mice to assess AD pathology. RESULTS: Our results demonstrated that the expression of the cystatin F protein was specifically increased in the monocytes of AD patients. Monocyte-derived cystatin F increased Aß deposition and exacerbated cognitive deficits in APP/PS1 mice. Furthermore, secreted cystatin F in the plasma of AD patients has a dimeric structure that is closely related to clinical signs of AD. Moreover, we noted that the cystatin F dimer blocks the phagocytosis of Aß by monocytes. Mechanistically, the cystatin F dimer physically interacts with Aß to inhibit its recognition and internalization by monocytes through certain amino acid interactions between the cystatin F dimer and Aß. We found that high levels of the cystatin F dimer protein in blood contributed to amyloid pathology and cognitive deficits as a risk factor in 5XFAD mice. CONCLUSIONS: Our findings highlight that the cystatin F dimer plays a crucial role in regulating Aß metabolism via its peripheral clearance pathway, providing us with a potential biomarker for diagnosis and potential target for therapeutic intervention.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Camundongos Transgênicos , Monócitos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Monócitos/metabolismo , Camundongos , Humanos , Peptídeos beta-Amiloides/metabolismo , Masculino , Feminino , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Idoso , Cistatinas/metabolismo , Cistatinas/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Idoso de 80 Anos ou mais , Camundongos Endogâmicos C57BL
3.
Skeletal Radiol ; 51(9): 1853-1863, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35347404

RESUMO

OBJECTIVE: To evaluate the performance and reliability of the single-energy metal artifact reduction (SEMAR) algorithm in patients with different orthopedic hardware at the hips. MATERIALS AND METHODS: A total of 153 patients with hip instrumentation who had undergone CT with adaptive iterative dose reduction (AIDR) 3D and SEMAR algorithms between February 2015 and October 2019 were included retrospectively. Patients were divided into 5 groups by the hardware type. Two readers with 21 and 13 years of experience blindly reviewed all image sets and graded the extent of artifacts and imaging quality using 5-point scales. To evaluate reliability, the mean densities and image noises were measured at the urinary bladder, veins, and fat in images with artifacts and the reference images. RESULTS: No significant differences were found in the mean densities of the urinary bladder, veins, and fat between the SEMAR images with artifacts (7.57 ± 9.49, 40.29 ± 23.07, 86.78 ± 38.34) and the reference images (7.77 ± 6.2, 40.27 ± 8.66, 89.10 ± 20.70) (P = .860, .994, .392). Image noises of the urinary bladder in the SEMAR images with artifacts (14.25 ± 4.50) and the SEMAR reference images (9.69 ± 1.29) were significantly higher than those in the AIDR 3D reference images (9.11 ± 1.12) (P < .001; P < .001). All AIDR 3D images were non-diagnostic (overall quality ≤ 3) and less than a quarter of the SEMAR images were non-diagnostic (16.7-23.7%), mainly in patients with prostheses [reader 1: 91.7% (22/24); reader 2: 92.6% (25/27)]. CONCLUSION: The SEMAR algorithm significantly reduces metal artifacts in CT images, more in patients with internal fixations than in patients with prostheses, and provides reliable attenuation of soft tissues.


Assuntos
Artefatos , Processamento de Imagem Assistida por Computador , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Metais , Reprodutibilidade dos Testes , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
4.
Foodborne Pathog Dis ; 19(5): 311-315, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35404143

RESUMO

Norovirus is a leading cause of acute gastroenteritis (AGE) in Taiwan. To improve diagnosis as part of laboratory surveillance, AGE surveillance was conducted using a new fluorescent probe hydrolysis-based insulated isothermal polymerase chain reaction (PCR) method, the POCKIT system, and the results were compared with those obtained from conventional methods. A total of 119 clinical stool samples from reported AGE outbreaks were collected for this study. From 83 real-time reverse transcription PCR (rRT-PCR) norovirus-positive cases, the POCKIT system identified 78 with a sensitivity of 90.3% in GI genogroup and 96.7% in GII genogroup. The specificity for both GI and GII genogroups was 100%. Overall, the POCKIT system is faster and easier to use than the conventional rRT-PCR method, and because of its high sensitivity and specificity, this system is a promising alternative for the detection of norovirus in patients with AGE, and would benefit public health laboratories for near real-time surveillance of AGE epidemic outbreaks.


Assuntos
Infecções por Caliciviridae , Norovirus , Infecções por Caliciviridae/diagnóstico , Infecções por Caliciviridae/epidemiologia , Diarreia/epidemiologia , Surtos de Doenças , Fezes , Genótipo , Humanos , Norovirus/genética , Patologia Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade
5.
Sensors (Basel) ; 22(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36146421

RESUMO

Vehicle fault detection and diagnosis (VFDD) along with predictive maintenance (PdM) are indispensable for early diagnosis in order to prevent severe accidents due to mechanical malfunction in urban environments. This paper proposes an early voiceprint driving fault identification system using machine learning algorithms for classification. Previous studies have examined driving fault identification, but less attention has focused on using voiceprint features to locate corresponding faults. This research uses 43 different common vehicle mechanical malfunction condition voiceprint signals to construct the dataset. These datasets were filtered by linear predictive coefficient (LPC) and wavelet transform(WT). After the original voiceprint fault sounds were filtered and obtained the main fault characteristics, the deep neural network (DNN), convolutional neural network (CNN), and long short-term memory (LSTM) architectures are used for identification. The experimental results show that the accuracy of the CNN algorithm is the best for the LPC dataset. In addition, for the wavelet dataset, DNN has the best performance in terms of identification performance and training time. After cross-comparison of experimental results, the wavelet algorithm combined with DNN can improve the identification accuracy by up to 16.57% compared with other deep learning algorithms and reduce the model training time by up to 21.5% compared with other algorithms. Realizing the cross-comparison of recognition results through various machine learning methods, it is possible for the vehicle to proactively remind the driver of the real-time potential hazard of vehicle machinery failure.


Assuntos
Condução de Veículo , Aprendizado Profundo , Algoritmos , Redes Neurais de Computação , Análise de Ondaletas
6.
Bioorg Med Chem Lett ; 31: 127715, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246109

RESUMO

The effects of 3 bufadienolides, namely kalantuboside B, kalantuboside A, and bryotoxin C, isolated from Kalanchoe tubiflora (Harvey) were evaluated and characterized in CL1-5 highly metastatic human lung cancer cells. In contrast to their apoptosis-promoting activity in other cancer cells, these bufadienolides only slight or did not induce apoptosis in CL1-5 cancer cells. Instead, they activated an autophagy pathway, as indicated by increased autophagosome formation. Autophagy induced by these bufadienolides was demonstrated to be linked to the down-regulation of p-mTOR and the up-regulation of LC3-II, ATG5, ATG7, and Beclin-1. Our findings revealed an autophagy as the alternative mechanism of drug action by bufadienolides in CL1-5 lung cancer cells and provided evidence that bufadienolides are a potential therapeutic strategy for highly metastatic human lung cancer.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Bufanolídeos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Bufanolídeos/síntese química , Bufanolídeos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
7.
BMC Geriatr ; 21(1): 590, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686133

RESUMO

OBJECTIVES: This research innovatively analyzed the marital transitions (i.e., divorce and widowhood) of older Taiwanese parents, their sleep problems and spousal specific characteristics (i.e., separate bedrooms for sleep and marital relationships) as well as their social and family connections, all of which were simultaneously reflected in emotional and social domains of loneliness. METHODS: Data are from 1645 older parents from Northern Taiwan. Loneliness was assessed by a De Jong-Gierveld short scale with emotional and social domains. We conducted multivariate logistic regression to examine the associations of marital transitions and family/social connections regarding sleep problems and psychological well-being with loneliness in social and emotional domains. Besides sleep problems and individual socioeconomic status, we included data on couples' sleeping arrangements and marital relationships. RESULTS: Social loneliness was significantly associated with being divorced (AOR = 1.80, 95% CI 1.13-2.86) and living alone (AOR = 1.50, 95% CI 1.02-2.23). In contrast, strong family cohesion and frequent weekly contact with friends were associated with lower social loneliness. Married parents who slept in separate bedrooms were more likely than bed-sharing couples to feel emotional and social loneliness, despite adjusting for their sleep problems. Furthermore, satisfactory spousal relationships significantly decreased the magnitude of associations in the social domain. DISCUSSION: Our findings support significant associations between loneliness in later life and major marital transitions, family and social connections and sleep problems which differ in social and emotional domains. Independent of relationship satisfaction, separate bedrooms relate to higher risks of emotional loneliness in older adults.


Assuntos
Solidão , Casamento , Idoso , Relações Familiares , Humanos , Pais , Sono , Apoio Social
8.
J Biol Chem ; 294(16): 6375-6386, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30792309

RESUMO

Contactin-associated protein 1 (CASPR1 or CNTNAP1) was recently reported to be expressed in brain microvascular endothelial cells (BMECs), the major component of the blood-brain barrier. To investigate CASPR1's physiological role in BMECs, here we used CASPR1 as a bait in a yeast two-hybrid screen to identify CASPR1-interacting proteins and identified the ß3 subunit of Na+/K+-ATPase (ATP1B3) as a CASPR1-binding protein. Using recombinant and purified CASPR1, RNAi, GST-pulldown, immunofluorescence, immunoprecipitation, and Na+/K+-ATPase activity assays, we found that ATP1B3's core proteins, but not its glycosylated forms, interact with CASPR1, which was primarily located in the endoplasmic reticulum of BMECs. CASPR1 knockdown reduced ATP1B3 glycosylation and prevented its plasma membrane localization, phenotypes that were reversed by expression of full-length CASPR1. We also found that the CASPR1 knockdown reduces the plasma membrane distribution of the α1 subunit of Na+/K+-ATPase, which is the major component assembled with ATP1B3 in the complete Na+/K+-ATPase complex. The binding of CASPR1 with ATP1B3, but not the α1 subunit, indicated that CASPR1 binds with ATP1B3 to facilitate the assembly of Na+/K+-ATPase. Furthermore, the activity of Na+/K+-ATPase was reduced in CASPR1-silenced BMECs. Interestingly, shRNA-mediated CASPR1 silencing reduced glutamate efflux through the BMECs. These results demonstrate that CASPR1 binds with ATP1B3 and thereby contributes to the regulation of Na+/K+-ATPase maturation and trafficking to the plasma membrane in BMECs. We conclude that CASPR1-mediated regulation of Na+/K+-ATPase activity is important for glutamate transport across the blood-brain barrier.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Membrana Celular/metabolismo , Células Endoteliais/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/metabolismo , Moléculas de Adesão Celular Neuronais/genética , Membrana Celular/genética , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Células Endoteliais/citologia , Deleção de Genes , Humanos , Microvasos/citologia , Microvasos/metabolismo , Ligação Proteica/fisiologia , Transporte Proteico/fisiologia , ATPase Trocadora de Sódio-Potássio/genética
9.
FASEB J ; 33(2): 1742-1757, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30183374

RESUMO

Small cell lung cancer (SCLC) is the most aggressive histologic subtype of lung cancer, with a strong predilection for early brain metastases. Despite efforts and advances in new therapeutics for SCLC, the prognosis of patients with SCLC with brain metastases is consistently poor. Therefore, a better understanding of the mechanisms of SCLC brain metastasis is important in improving current treatments. In this study, elevated S100A16 levels were associated with SCLC brain metastases, which was a possible secondary event arising from the brain metastatic microenvironment. Using an in vitro cell coculture system, we found that the coculturing of SCLC cells with human brain microvascular endothelial cells (HBMECs) led to an increased expression of S100A16 in SCLC cells. Conversely, treatment of HBMECs with GW4869, an inhibitor of exosome release, significantly blocked this effect in the cocultured SCLC cells. Alternatively, the results from Western blot analyses and immunofluorescence indicated that the HBMEC exosomes purified by ultracentrifugation also induced the elevation and translocation from the cytoplasm to the nucleus of S100A16 in the recipient SCLC cells. The inhibition experiments demonstrated that elevated S100A16 contributed a benefit of HBMEC exosomes for the survival of the recipient SCLC cells under stress. Moreover, the elevation of S100A16 in SCLC cells prevented the loss of mitochondrial membrane potential (Δψm) and enhanced resistance to apoptosis under stressful conditions, which were determined by Annexin V/propidium iodide and JC-1 assay. Further results showed that the S100A16-mediated protective effect was caused by the presence of an important element in Δψm, prohibitin (PHB)-1, a protein in the mitochondrial inner membrane. Conversely, the delivery of PHB-1 siRNAs into S100A16 overexpressing SCLC cells weakened these protective effects. Our findings suggest that elevated S100A16 plays an active role in facilitating the survival of SCLC cells through modulating the mitochondrial function, identifying S100A16 as an important potential target in SCLC brain metastasis.-Xu, Z.-H., Miao, Z.-W., Jiang, Q.-Z., Gan, D.-X., Wei, X.-G., Xue, X.-Z., Li, J.-Q., Zheng, F., Qin, X.-X., Fang, W.-G., Chen, Y.-H., Li. B. Brain microvascular endothelial cell exosome-mediated S100A16 up-regulation confers small cell lung cancer cell survival in brain.


Assuntos
Neoplasias Encefálicas/secundário , Encéfalo/irrigação sanguínea , Carcinoma de Células Pequenas/patologia , Sobrevivência Celular , Endotélio Vascular/metabolismo , Exossomos/fisiologia , Neoplasias Pulmonares/patologia , Proteínas S100/metabolismo , Regulação para Cima , Animais , Encéfalo/patologia , Neoplasias Encefálicas/metabolismo , Carcinoma de Células Pequenas/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proibitinas
10.
Med Microbiol Immunol ; 208(1): 59-68, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30171337

RESUMO

Escherichia coli K1 is the most common Gram-negative bacteria causing neonatal meningitis. Polymorphonuclear leukocyte (PMN) transmigration across the blood-brain barrier (BBB) is the hallmark of bacterial meningitis. Reportedly, the deletion of virulence factor cglD (E44:ΔcglD) from E44 is responsible for a less efficient PMN transendothelial migration ability. In the present study, we found that complementation of the cglD gene into E44:ΔcglD mutant strain might restore the PMN count and myeloperoxidase level in a neonatal mouse meningitis. Using human brain microvascular endothelial cells (HBMECs), the main model of the BBB in vitro, we found that E44:ΔcglD mutant strain induced a less efficient PMN adhesion to HBMECs and down-regulated chemokines CXCL1, CXCL6 and CXCL8 and adhesion molecule E-selectin, compared with the E44 strain. Complementation of cglD restored the PMN adhesion to HBMECs and the level of these proteins. E44:ΔcglD mutant strain also induced a less efficient NF-κB pathway activation in HBMECs and reduced the soluble p65 (sp65) level in the cerebral spinal fluid of newborn mice, compared with the E44 strain. Complementation of cglD restored the NF-κB pathway activation and increased the sp65 levels. This suggests that cglD in E44 contributes to NF-κB pathway activation in the brain endothelium to promote PMN adhesion to HBMECs and transendothelial migration. Our identified novel requirement of cglD for immune activation and subsequent PMN entry into the central nervous system suggests that therapies directed at neutralising this molecule will be beneficial in preventing bacterial meningitis progression.


Assuntos
Proteínas de Bactérias/metabolismo , Células Endoteliais/efeitos dos fármacos , Endotélio/efeitos dos fármacos , Escherichia coli/patogenicidade , Meningites Bacterianas/patologia , Neutrófilos/imunologia , Migração Transendotelial e Transepitelial , Fatores de Virulência/metabolismo , Animais , Animais Recém-Nascidos , Antígenos de Bactérias/análise , Adesão Celular , Células Cultivadas , Líquido Cefalorraquidiano/química , Modelos Animais de Doenças , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Feminino , Deleção de Genes , Teste de Complementação Genética , Humanos , Recém-Nascido , Masculino , Camundongos , Polissacarídeos Bacterianos/análise , Fator de Transcrição RelA/análise
11.
Zhonghua Nan Ke Xue ; 24(1): 50-54, 2018.
Artigo em Zh | MEDLINE | ID: mdl-30157360

RESUMO

OBJECTIVE: To investigate the clinical value of contrast-enhanced ultrasonography (CEUS) in the diagnosis of prostate cancer in patients with different concentrations of prostate-specific antigen (PSA). METHODS: Based on the PSA concentration, 186 patients were divided into three groups (PSA 4-10 µg/L, 11-20 µg/L, and >20 µg/L) and underwent transrectal CEUS and biopsy. We compared the pathological results with the CEUS features in different groups of patients and performed a statistical analysis on the characteristics of the CEUS manifestations of prostate cancer and benign prostatic lesions. RESULTS: Of the 186 patients, 118 (63.4%) were diagnosed by biopsy with prostate cancer and the other 68 (36.6%) with benign prostatic lesions. The positive rate of CEUS in the diagnosis of prostate cancer was above 95% in all the three groups, significantly higher than that of conventional ultrasound in the PSA 4-10 and >10-20 µg/L groups (P <0.01). CONCLUSIONS: Contrast-enhanced ultrasonography can achieve a high detection rate in the diagnosis of prostate cancer, especially for the patients with a low PSA concentration, and therefore can be used as one of the most valuable diagnostic techniques for this purpose.


Assuntos
Meios de Contraste , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Ultrassonografia/métodos , Biópsia , Humanos , Masculino , Próstata/diagnóstico por imagem , Próstata/patologia , Doenças Prostáticas/sangue , Doenças Prostáticas/diagnóstico por imagem , Doenças Prostáticas/patologia , Neoplasias da Próstata/patologia , Ultrassonografia/estatística & dados numéricos
12.
Nat Chem Biol ; 11(3): 189-91, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25622091

RESUMO

PAD4 has been strongly implicated in the pathogenesis of autoimmune, cardiovascular and oncological diseases through clinical genetics and gene disruption in mice. New selective PAD4 inhibitors binding a calcium-deficient form of the PAD4 enzyme have validated the critical enzymatic role of human and mouse PAD4 in both histone citrullination and neutrophil extracellular trap formation for, to our knowledge, the first time. The therapeutic potential of PAD4 inhibitors can now be explored.


Assuntos
Benzimidazóis/farmacologia , Inibidores Enzimáticos/farmacologia , Hidrolases/antagonistas & inibidores , Neutrófilos/efeitos dos fármacos , Animais , Benzimidazóis/síntese química , Ligação Competitiva , Cálcio/metabolismo , Citrulina/metabolismo , Inibidores Enzimáticos/síntese química , Células HEK293 , Histonas/metabolismo , Humanos , Técnicas In Vitro , Camundongos , Modelos Moleculares , Proteína-Arginina Desiminase do Tipo 4 , Desiminases de Arginina em Proteínas , Bibliotecas de Moléculas Pequenas , Especificidade por Substrato
13.
Int J Mol Sci ; 18(5)2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28467355

RESUMO

The formation of brain vasculature is an essential step during central nervous system development. The molecular mechanism underlying brain angiogenesis remains incompletely understood. The role of Atg7, an autophagy-related protein, in brain angiogenesis was investigated in this study. We found that the microvessel density in mice brains with endothelial-specific knockout of Atg7 (Atg7 EKO) was significantly decreased compared to wild-type control. Consistently, in vitro angiogenesis assays showed that Atg7 knockdown impaired angiogenesis in brain microvascular endothelial cells. Further results indicated that knockdown of Atg7 reduced interleukin-6 (IL-6) expression in brain microvascular endothelial cells, which is mediated by NF-κB-dependent transcriptional control. Interestingly, exogenous IL-6 restored the impaired angiogenesis and reduced cell motility caused by Atg7 knockdown. These results demonstrated that Atg7 has proangiogenic activity in brain angiogenesis which is mediated by IL-6 production in a NF-κB-dependent manner.


Assuntos
Proteína 7 Relacionada à Autofagia/metabolismo , Encéfalo/irrigação sanguínea , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Neovascularização Fisiológica/fisiologia , Análise de Variância , Animais , Proteína 7 Relacionada à Autofagia/genética , Movimento Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais , Humanos , Camundongos , Camundongos Knockout , Microvasos/crescimento & desenvolvimento , Microvasos/metabolismo , Neovascularização Fisiológica/genética
14.
Mol Genet Genomics ; 290(5): 1943-53, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25920486

RESUMO

In insects, cytochrome P450 monooxygenases (P450s) are involved in the metabolism of endogenous compounds such as steroid hormones and lipids. In this study, we measured the 20-hydroxyecdysone (20E)-induced transcriptional level of the CYP6ab4 gene using reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) with a dual spike-in strategy. We then probed possible physiological functions using RNAi experiments in the silkworm Bombyx mori. The activity of the CYP6ab4 promoter in various silkworm tissues was measured by firefly luciferase activity and normalized by Renilla luciferase activity. Our results showed that the activity of the CYP6ab4 promoter was highest in the malpighian tubule, followed by the fat body, the silk gland, the midgut, the epidermis, and the hemocyte. The essential region for basal and 20E-induced transcriptional activity was between -908 and -456 bp from the transcription start site. Through promoter truncation analysis using a dual-luciferase reporter assay in B. mori ovary cells (BmN), we showed that the region between -827 and -722 bp was essential for basal and 20E-induced transcriptional activity. Sequence analysis of this region revealed several potential transcriptional regulatory elements such as Hunchback (Hb) and BR-C Z. Mutation of the core bases of the BR-C Z binding site demonstrated that BR-C Z induces 20E-mediated CYP6ab4 transcription. Further identification of cis- and trans-elements and their roles in the upregulation of CYP6ab4 may be useful for elucidating the contribution of P450 to the response mechanism to 20E.


Assuntos
Bombyx/genética , Citocromos c/genética , Regiões Promotoras Genéticas , Interferência de RNA , Animais , Sequência de Bases , Bombyx/crescimento & desenvolvimento , DNA/genética , Técnicas de Silenciamento de Genes , Inativação Gênica , Larva/enzimologia , Dados de Sequência Molecular , Transcrição Gênica
15.
Alzheimer Dis Assoc Disord ; 29(1): 63-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24759545

RESUMO

The aim of this study was to investigate the changes in the protein, cholesterol, and ganglioside GM1 content of lipid rafts in platelets from patients with Alzheimer disease (AD), and identify potential blood biomarkers of the disease. A total of 31 Chinese patients with AD and 31 aged-matched control subjects were selected. Lipid rafts were isolated from platelets using Optiprep gradient centrifugation. The protein content of lipid rafts was evaluated using Micro BCA assay, the cholesterol content using molecular probes, ganglioside GM1 content using colorimetry and dot-blotting analysis. The results showed that the cholesterol and ganglioside GM1 content of lipid rafts from platelets was significantly higher in patients with AD than aged-matched control subjects, whereas the protein content of lipid rafts did not show any differences between the 2 groups. These results indicate that the increases in the cholesterol and ganglioside GM1 content of lipid rafts from the platelets of patients with AD might serve as a biochemical adjunct to the clinical diagnosis of AD.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Povo Asiático , Colesterol/sangue , Gangliosídeo G(M1)/sangue , Microdomínios da Membrana/metabolismo , Idoso , Doença de Alzheimer/psicologia , Povo Asiático/psicologia , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Neurochem Res ; 39(4): 700-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24526602

RESUMO

Bone marrow-derived mesenchymal stem cells (MSCs) transplant into the brain, where they play a potential therapeutic role in neurological diseases. However, the blood-brain barrier (BBB) is a native obstacle for MSCs entry into the brain. Little is known about the mechanism behind MSCs migration across the BBB. In the present study, we modeled the interactions between human MSCs (hMSCs) and human brain microvascular endothelial cells (HBMECs) to mimic the BBB microenvironment. Real-time PCR analysis indicated that the chemokine CXCL11 is produced by hMSCs and the chemokine receptor CXCR3 is expressed on HBMECs. Further results indicate that CXCL11 secreted by hMSCs may interact with CXCR3 on HBMECs to induce the disassembly of tight junctions through the activation of ERK1/2 signaling in the endothelium, which promotes MSCs transendothelial migration. These findings are relevant for understanding the biological responses of MSCs in BBB environments and helpful for the application of MSCs in neurological diseases.


Assuntos
Movimento Celular/fisiologia , Quimiocina CXCL11/metabolismo , Células Endoteliais/metabolismo , Células-Tronco Mesenquimais/metabolismo , Microvasos/metabolismo , Receptores CXCR3/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Medula Óssea/metabolismo , Células Cultivadas , Humanos , Masculino , Ligação Proteica/fisiologia , Ratos , Ratos Wistar
17.
Mol Biol Rep ; 41(3): 1607-16, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24415296

RESUMO

Carboxylesterase (CarE) is a multifunctional superfamily, and it plays important roles in xenobiotic detoxification, pheromone degradation, neurogenesis and regulating development. In this research, firstly, we measured the rutin-induced transcriptional level of BmCarE-10 gene by using real-time quantitative RT-PCR method, and dual spike-in strategy. Several possible physiological functions were certified preliminarily by RNAi experiments in silkworm. Promoter truncation analysis using a dual-luciferase reporter assay in Bombyx mori ovary cells (BmN) showed that the region -705 to -625 for BmCarE-10 gene was essential for basal and rutin-induced transcriptional activity. Sequence analysis of this region revealed several potential transcriptional regulatory elements such as Croc and Dfd. The activities of the BmCarE-10 promoter in various tissues of silkworm were also measured by firefly luciferase activity and normalized by the Renilla luciferase activity. Results showed that the activity of the BmCarE-10 promoter were highest in the Malpighian tubule, followed by fat body, silk gland, midgut, epidermis, and hemocyte. The essential region for basal and rutin-induced transcriptional activity was also -894 to -502 in Malpighian tubule and fat body of silkworm. The potential core promoters of BmCarE-10 gene in B. mori are reported for the first time in this research. Further identification of cis- and trans-elements and their role in upregulation of BmCarE-10 gene may be useful for elucidating the contribution of CarE protein to the response mechanism to rutin.


Assuntos
Bombyx/genética , Carboxilesterase/biossíntese , Ovário/metabolismo , Interferência de RNA , Animais , Bombyx/metabolismo , Carboxilesterase/genética , Clonagem Molecular , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Larva , Ovário/citologia , Regiões Promotoras Genéticas , Rutina/farmacologia
18.
Br J Pharmacol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38803135

RESUMO

The immunotherapy revolution with the use of immune checkpoint inhibitors (ICIs) started with the clinical use of the first ICI, ipilimumab, in 2011. Since then, the field of ICI therapy has rapidly expanded - with the FDA approval of 10 different ICI drugs so far and their incorporation into the therapeutic regimens of a range of malignancies. While ICIs have shown high anti-cancer efficacy, they also have characteristic side effects, termed immune-related adverse events (irAEs). These side effects hinder the therapeutic potential of ICIs and, therefore, finding ways to prevent and treat them is of paramount importance. The current protocols to manage irAEs follow an empirical route of steroid administration and, in more severe cases, ICI withdrawal. However, this approach is not optimal in many cases, as there are often steroid-refractory irAEs, and there is a potential for corticosteroid use to promote tumour progression. This review surveys the current alternative approaches to the treatments for irAEs, with the goal of summarizing and highlighting the best attempts to treat irAEs, without compromising anti-tumour immunity and allowing for rechallenge with ICIs after resolution of the irAEs.

19.
Heliyon ; 10(1): e23426, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38173512

RESUMO

Ischemia-reperfusion (I/R) injury constitutes a significant risk factor for a range of diseases, including ischemic stroke, myocardial infarction, and trauma. Following the restoration of blood flow post-tissue ischemia, oxidative stress can lead to various forms of cell death, including necrosis, apoptosis, autophagy, and necroptosis. Recent evidence has highlighted the crucial role of mitochondrial dysfunction in I/R injury. Nevertheless, there remains much to be explored regarding the molecular signaling network governing cell death under conditions of oxidative stress. Voltage-dependent anion channel 1 (VDAC1), a major component in the outer mitochondrial membrane, is closely involved in the regulation of cell death. In a cellular model of oxygen-glucose deprivation and reoxygenation (OGD/R), which effectively simulates I/R injury in vitro, our study reveals that OGD/R induces VDAC1 oligomerization, consequently exacerbating cell death. Furthermore, we have revealed the translocation of mixed lineage kinase domain-like protein (MLKL) to the mitochondria, where it interacts with VDAC1 following OGD/R injury, leading to an increased mitochondrial membrane permeability. Notably, the inhibition of MLKL by necrosulfonamide hinders the binding of MLKL to VDAC1, primarily by affecting the membrane translocation of MLKL, and reduces OGD/R-induced VDAC1 oligomerization. Collectively, our findings provide preliminary evidence of the functional association between MLKL and VDAC1 in the regulation of necroptosis.

20.
Chem Sci ; 15(20): 7659-7666, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38779171

RESUMO

The development of high-quality organic scintillators encounters challenges primarily associated with the weak X-ray absorption ability resulting from the presence of low atomic number elements. An effective strategy involves the incorporation of halogen-containing molecules into the system through co-crystal engineering. Herein, we synthesized a highly fluorescent dye, 2,5-di(4-pyridyl)thiazolo[5,4-d]thiazole (Py2TTz), with a fluorescence quantum yield of 12.09%. Subsequently, Py2TTz was co-crystallized with 1,4-diiodotetrafluorobenzene (I2F4B) and 1,3,5-trifluoro-2,4,6-triiodobenzene (I3F3B) obtaining Py2TTz-I2F4 and Py2TTz-I3F3. Among them, Py2TTz-I2F4 exhibited exceptional scintillation properties, including an ultrafast decay time (1.426 ns), a significant radiation luminescence intensity (146% higher than Bi3Ge4O12), and a low detection limit (70.49 nGy s-1), equivalent to 1/78th of the detection limit for medical applications (5.5 µGy s-1). This outstanding scintillation performance can be attributed to the formation of halogen-bonding between I2F4B and Py2TTz. Theoretical calculations and single-crystal structures demonstrate the formation of halogen-bond-induced rather than π-π-induced charge-transfer cocrystals, which not only enhances the X-ray absorption ability and material conductivity under X-ray exposure, but also constrains molecular vibration and rotation, and thereby reducing non-radiative transition rate and sharply increasing its fluorescence quantum yields. Based on this, the flexible X-ray film prepared based on Py2TTz-I2F4 achieved an ultrahigh spatial resolution of 26.8 lp per mm, underscoring the superiority of this strategy in developing high-performance organic scintillators.

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