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1.
Brain ; 146(8): 3373-3391, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36825461

RESUMO

GGC repeat expansion in the 5' untranslated region (UTR) of NOTCH2NLC is associated with a broad spectrum of neurological disorders, especially neuronal intranuclear inclusion disease (NIID). Studies have found that GGC repeat expansion in NOTCH2NLC induces the formation of polyglycine (polyG)-containing protein, which is involved in the formation of neuronal intranuclear inclusions. However, the mechanism of neurotoxicity induced by NOTCH2NLC GGC repeats is unclear. Here, we used NIID patient-specific induced pluripotent stem cell (iPSC)-derived 3D cerebral organoids (3DCOs) and cellular models to investigate the pathophysiological mechanisms of NOTCH2NLC GGC repeat expansion. IPSC-derived 3DCOs and cellular models showed the deposition of polyG-containing intranuclear inclusions. The NOTCH2NLC GGC repeats could induce the upregulation of autophagic flux, enhance integrated stress response and activate EIF2α phosphorylation. Bulk RNA sequencing for iPSC-derived neurons and single-cell RNA sequencing (scRNA-seq) for iPSC-derived 3DCOs revealed that NOTCH2NLC GGC repeats may be associated with dysfunctions in ribosome biogenesis and translation. Moreover, NOTCH2NLC GGC repeats could induce the NPM1 nucleoplasm translocation, increase nucleolar stress, impair ribosome biogenesis and induce ribosomal RNA sequestration, suggesting dysfunction of membraneless organelles in the NIID cellular model. Dysfunctions in ribosome biogenesis and phosphorylated EIF2α and the resulting increase in the formation of G3BP1-positive stress granules may together lead to whole-cell translational inhibition, which may eventually cause cell death. Interestingly, scRNA-seq revealed that NOTCH2NLC GGC repeats may be associated with a significantly decreased proportion of immature neurons while 3DCOs were developing. Together, our results underscore the value of patient-specific iPSC-derived 3DCOs in investigating the mechanisms of polyG diseases, especially those caused by repeats in human-specific genes.


Assuntos
DNA Helicases , RNA Helicases , Humanos , Proteínas de Ligação a Poli-ADP-Ribose , Proteínas com Motivo de Reconhecimento de RNA , Regiões 5' não Traduzidas , Corpos de Inclusão Intranuclear , Ribossomos , Expansão das Repetições de Trinucleotídeos/genética
2.
Mov Disord ; 38(12): 2258-2268, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37990409

RESUMO

BACKGROUND: Patients with Parkinson's disease (PD) have consistently demonstrated brain structure abnormalities, indicating the presence of shared etiological and pathological processes between PD and brain structures; however, the genetic relationship remains poorly understood. OBJECTIVE: The aim of this study was to investigate the extent of shared genetic architecture between PD and brain structural phenotypes (BSPs) and to identify shared genomic loci. METHODS: We used the summary statistics from genome-wide association studies to conduct MiXeR and conditional/conjunctional false discovery rate analyses to investigate the shared genetic signatures between PD and BSPs. Subsequent expression quantitative trait loci mapping in the human brain and enrichment analyses were also performed. RESULTS: MiXeR analysis identified genetic overlap between PD and various BSPs, including total cortical surface area, average cortical thickness, and specific brain volumetric structures. Further analysis using conditional false discovery rate (FDR) identified 21 novel PD risk loci on associations with BSPs at conditional FDR < 0.01, and the conjunctional FDR analysis demonstrated that PD shared several genomic loci with certain BSPs at conjunctional FDR < 0.05. Among the shared loci, 16 credible mapped genes showed high expression in the brain tissues and were primarily associated with immune function-related biological processes. CONCLUSIONS: We confirmed the polygenic overlap with mixed directions of allelic effects between PD and BSPs and identified multiple shared genomic loci and risk genes, which are likely related to immune-related biological processes. These findings provide insight into the complex genetic architecture associated with PD. © 2023 International Parkinson and Movement Disorder Society.


Assuntos
Estudo de Associação Genômica Ampla , Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/genética , Predisposição Genética para Doença/genética , Fenótipo , Encéfalo/diagnóstico por imagem , Polimorfismo de Nucleotídeo Único/genética , Loci Gênicos
3.
J Headache Pain ; 24(1): 111, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592229

RESUMO

BACKGROUND: While previous genome-wide association studies (GWAS) have identified multiple risk variants for migraine, there is a lack of evidence about how these variants contribute to the development of migraine. We employed an integrative pipeline to efficiently transform genetic associations to identify causal genes for migraine. METHODS: We conducted a proteome-wide association study (PWAS) by combining data from the migraine GWAS data with proteomic data from the human brain and plasma to identify proteins that may play a role in the risk of developing migraine. We also combined data from GWAS of migraine with a novel joint-tissue imputation (JTI) prediction model of 17 migraine-related human tissues to conduct transcriptome-wide association studies (TWAS) together with the fine mapping method FOCUS to identify disease-associated genes. RESULTS: We identified 13 genes in the human brain and plasma proteome that modulate migraine risk by regulating protein abundance. In addition, 62 associated genes not reported in previous migraine TWAS studies were identified by our analysis of migraine using TWAS and fine mapping. Five genes including ICA1L, TREX1, STAT6, UFL1, and B3GNT8 showed significant associations with migraine at both the proteome and transcriptome, these genes are mainly expressed in ependymal cells, neurons, and glial cells, and are potential target genes for prevention of neuronal signaling and inflammatory responses in the pathogenesis of migraine. CONCLUSIONS: Our proteomic and transcriptome findings have identified disease-associated genes that may give new insights into the pathogenesis and potential therapeutic targets for migraine.


Assuntos
Transtornos de Enxaqueca , Proteoma , Humanos , Proteoma/genética , Estudo de Associação Genômica Ampla , Proteômica , Transcriptoma , Transtornos de Enxaqueca/genética
4.
Acta Radiol ; 63(12): 1712-1720, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34859686

RESUMO

BACKGROUND: Isolated aortic brachiocephalic artery (IABA) is a rare congenital aortic arch anomaly. It is difficult to diagnose IABA prenatally and the prevalence in the prenatal population is unknown. PURPOSE: To evaluate the echocardiographic characteristics and associations in fetuses with IABA. MATERIAL AND METHODS: We retrospectively analyzed all cases of prenatal diagnosis of IABA from January 2012 to November 2020 and reviewed the follow-up results. Copy Number Variation Sequencing (CNV-Seq) was performed using the biological specimens of the of the fetuses and family members. RESULTS: Ten cases (10/45652, 0.022%) of IABA were identified in our center. The prevalence of the cases with isolated left subclavian artery (ILSCA) in the right aortic arch (RAA) population was 0.98% (6/613). The ILSCA was the most common isolated arch branch. All the isolated branches were on the opposite side of aortic arch in all the cases. The "ice stick" sign in the coronal section could be seen in most cases of IABA. Of the 10 cases, 8 (8/10, 80%) were associated with tetralogy of Fallot (TOF). Two cases of IABA were combined with 22q11.2 deletion syndrome. CONCLUSION: IABA is a rare aortic anomaly. ILSCA was the most common isolated arch branch and TOF was the most common associated intra-cardiac anomaly. The "ice stick" sign in the coronal section could indicate a diagnosis of the IABA.


Assuntos
Variações do Número de Cópias de DNA , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Aorta Torácica/diagnóstico por imagem , Tronco Braquiocefálico/diagnóstico por imagem , Diagnóstico Pré-Natal , Estudos Retrospectivos , Ultrassonografia Pré-Natal/métodos
5.
Echocardiography ; 35(4): 563-565, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29430703

RESUMO

Berry syndrome is a rare congenital cardiac malformation. We describe 4 cases of Berry syndrome diagnosed by fetal echocardiography. Based on our experience, the three-vessel view is important for diagnosing the aortopulmonary window and aortic origin of the right pulmonary artery. Furthermore, the true cross-sectional and sagittal views obtained by continuously scanning from the three-vessel-trachea view to the long-axis view of the aortic arch are required to image the interruption or coarctation of the aortic arch. An early and accurate prenatal diagnosis of Berry syndrome is feasible and helps to improve patient outcomes.


Assuntos
Ecocardiografia/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Adulto , Ecocardiografia Doppler em Cores , Evolução Fatal , Feminino , Coração Fetal/diagnóstico por imagem , Humanos , Gravidez , Síndrome
6.
Pharm Biol ; 52(3): 356-61, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24143857

RESUMO

CONTEXT: Polygonum cuspidatum Sieb et Zucc. (Polygonaceae) possesses various pharmacological activities and has been widely using as one of the most popular and valuable Chinese herbal medicines in clinics. Its usage has increasingly attracted much of our attention and urges investigation on its bioactive components. OBJECTIVE: To establish a rapid and valid approach for screening potential neuroprotective components from P. cuspidatum. MATERIALS AND METHODS: Potential neuroprotective components from P. cuspidatum were screened utilizing liposome equilibrium dialysis followed by high-performance liquid chromatography (HPLC) analysis. Their neuroprotective effects on modulation of protein expression of α7 nAChR, α3 nAChR and synaptophysin (SPY) on SH-SY5Y human neuroblastoma cell line (SH-SY5Y) were evaluated by means of Western blotting. RESULTS: Two potential compounds, polydatin (C1) and emodin-8-O-ß-D-glucoside (C2), were detected and identified in our study. The biological tests showed that both compounds C1 and C2, respectively, at concentrations of 0.1 and 0.25 mg/mL significantly increased protein expression of α7 and α3 nicotinic acetylcholine receptors (nAChRs) in SH-SY5Y cells. Moreover, C1 and C2 at 0.1 mg/mL significantly reversed the Aß1₋42-induced decrease of α7 and α3 nAChRs protein expression in SH-SY5Y cells. In addition, C2 at 0.1 mg/mL significantly increased protein expression of SPY in SH-SY5Y cells and Aß11₋42-induced SH-SY5Y cells whereas C1 did not provide any positive effects. DISCUSSION AND CONCLUSION: In conclusion, our approach utilizing liposome equilibrium dialysis combined with HPLC analysis and cell-based assays is a prompt and useful method for screening neuroprotective agents.


Assuntos
Fallopia japonica/química , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Antraquinonas/administração & dosagem , Antraquinonas/isolamento & purificação , Antraquinonas/farmacologia , Western Blotting , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Diálise/métodos , Relação Dose-Resposta a Droga , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosídeos/administração & dosagem , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Humanos , Lipossomos , Neuroblastoma/patologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/isolamento & purificação , Permeabilidade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Receptores Nicotínicos/genética , Estilbenos/administração & dosagem , Estilbenos/isolamento & purificação , Estilbenos/farmacologia , Receptor Nicotínico de Acetilcolina alfa7/genética
7.
Front Aging Neurosci ; 16: 1403077, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903900

RESUMO

Introduction: Alzheimer's disease (AD) is the most widespread neurodegenerative disease in the world. Previous studies have shown that peripheral immune dysregulation plays a paramount role in AD, but whether there is a protective causal relationship between peripheral immunophenotypes and AD risk remains ambiguous. Methods: Two-sample Mendelian randomization (MR) was performed using large genome-wide association study (GWAS) genetic data to assess causal effects between peripheral immunophenotypes and AD risk. Utilizing the genetic associations of 731 immune cell traits as exposures. We adopted the inverse variance weighted method as the primary approach. The Weighted median and MR-Egger regression methods were employed as supplements. Various sensitivity analyses were performed to assess the robustness of the outcomes. Results: Based on the IVW method, we identified 14 immune cell traits that significantly reduced the risk of AD, of which six demonstrated statistical significance in both IVW and Weighted median methods. Among the seven immune traits, four were related to regulatory T (Treg) cells : (1) CD25++ CD45RA- CD4 not regulatory T cell % T cell (odds ratio (OR) [95% confidence interval (CI)] = 0.96 [0.95, 0.98], adjusted P = 1.17E-02), (2) CD25++ CD45RA- CD4 not regulatory T cell % CD4+ T cell (OR [95% CI] = 0.97 [0.96, 0.99], adjusted P = 3.77E-02), (3) Secreting CD4 regulatory T cell % CD4 regulatory T cell (OR [95% CI] = 0.98 [0.97, 0.99], adjusted P = 7.10E-03), (4) Activated & secreting CD4 regulatory T cell % CD4 regulatory T cell(OR [95% CI] = 0.98 [0.97, 0.99], adjusted P = 7.10E-03). In addition, HLA DR++ monocyte % monocyte (OR [95% CI] = 0.93 [0.89, 0.98], adjusted P = 4.87E-02) was associated with monocytes, and HLA DR on myeloid Dendritic Cell (OR [95% CI] = 0.93 [0.89, 0.97], adjusted P = 1.17E-02) was related to dendritic cells (DCs). Conclusion: These findings enhance the comprehension of the protective role of peripheral immunity in AD and provide further support for Treg and monocyte as potential targets for immunotherapy in AD.

8.
Aging (Albany NY) ; 16(2): 1555-1580, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38240717

RESUMO

Genome-wide association studies (GWAS) have identified multiple risk variants for Parkinson's disease (PD). Nevertheless, how the risk variants confer the risk of PD remains largely unknown. We conducted a proteome-wide association study (PWAS) and summary-data-based mendelian randomization (SMR) analysis by integrating PD GWAS with proteome and protein quantitative trait loci (pQTL) data from human brain, plasma and CSF. We also performed a large transcriptome-wide association study (TWAS) and Fine-mapping of causal gene sets (FOCUS), leveraging joint-tissue imputation (JTI) prediction models of 22 tissues to identify and prioritize putatively causal genes. We further conducted PWAS, SMR, TWAS, and FOCUS using a multi-trait analysis of GWAS (MTAG) to identify additional PD risk genes to boost statistical power. In this large-scale study, we identified 16 genes whose genetically regulated protein abundance levels were associated with Parkinson's disease risk. We undertook a large-scale analysis of PD and correlated traits, through TWAS and FOCUS studies, and discovered 26 casual genes related to PD that had not been reported in previous TWAS. 5 genes (CD38, GPNMB, RAB29, TMEM175, TTC19) showed significant associations with PD at both the proteome-wide and transcriptome-wide levels. Our study provides new insights into the etiology and underlying genetic architecture of PD.


Assuntos
Doença de Parkinson , Transcriptoma , Humanos , Estudo de Associação Genômica Ampla , Proteoma/genética , Predisposição Genética para Doença , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único , Glicoproteínas de Membrana/genética
9.
NPJ Parkinsons Dis ; 10(1): 70, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548756

RESUMO

This study aimed to investigate the association between irritable bowel syndrome (IBS) and Parkinson's disease (PD) utilizing prospective cohort study and Mendelian randomization. The dataset contained a substantial cohort of 426,911 participants from the UK Biobank, discussing the association between IBS and PD with Cox proportional hazards models and case-control analysis while adjusting for covariates such as age, gender, ethnicity and education level. In univariate Cox regression model, the risk of PD was reduced in IBS patients (HR: 0.774, 95%CI: 0.625-0.956, P = 0.017), but the statistical significance diminished in the three models after adjusting for other variables. In a few subgroup analyses, IBS patients are less likely to develop into PD, and patients diagnosed with IBS after 2000 also had a lower risk (HR: 0.633, 95%CI: 0.403-0.994, P = 0.047) of subsequently developing PD. In addition, we matched five healthy control participants based on gender and age at the end of the study for each IBS patient diagnosed during the follow-up period, and logistic regression results (OR:1.239, 95%CI: 0.896-1.680, P = 0.181) showed that IBS was not associated with the risk of PD. Mendelian randomization did not find significant evidence of the causal relationship between IBS and Parkinson's disease (OR: 0.801, 95%CI: 0.570-1.278, P = 0.204). Overall, we suggest that IBS status is not associated with the risk of developing PD, and that these findings provide valuable insights into the clinical management and resource allocation of patients with IBS.

10.
Front Neurol ; 14: 1237847, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37830085

RESUMO

This report presents a case of pontine autosomal dominant microangiopathy with leukoencephalopathy (PADMAL) in a 35 year-old male patient. The patient exhibited a consistent history of recurrent ischemic strokes, concentrated primarily in the pons region, accompanied by concurrent manifestations of leukoencephalopathy and microbleeds. Genetic evaluation revealed a heterozygous missense mutation consistent with c.3431C>G, p. Thr1144Arg substitution within exon 40 of the COL4A1 gene. This mutation was also identified in the patient's mother, affirming an autosomal dominant inheritance model. Our findings serve as testament to the potential role of mutation in the exon 40 of COL4A1 in the pathogenesis and progression of PADMAL, contributing to ongoing efforts aimed at better understanding the genetic basis of this debilitating disorder.

11.
Int J Stroke ; 18(1): 109-116, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367219

RESUMO

BACKGROUND: Lacunar stroke accounts for a quarter of all strokes, but little is known about the underlying pathological mechanisms. Analysis of serum metabolites may allow better understanding of the underlying biological processes. Mendelian randomization (MR) can provide information on the causality of associations. AIMS: To identify causal relationships between serum metabolites and lacunar stroke. METHODS: We applied a two-sample MR analysis to evaluate relationships between 486 serum metabolites and lacunar stroke. The inverse-variance weighted (IVW) method was used to estimate the causal relationship of the exposure on the outcome, while sensitivity analyses were performed using MR-Egger, weighted median, and MR-PRESSO to eliminate the pleiotropy. We also performed a metabolic pathway analysis to identify potential metabolic pathways. RESULTS: We identified 15 known (8 risk and 7 protective) and 14 unknown serum metabolites associated with lacunar stroke. Among the known risk metabolites, two were lipids (1-linoleoylglycerophosphoethanolamine and dihomo-linolenate (20:3n3 or n6)), five amino acids (kynurenine, isobutyrylcarnitine, aspartate, trans-4-hydroxyproline, and 3-methyl-2-oxovalerate), and one peptide (ADSGEGDFXAEGGGVR). The known protective metabolites included four lipids (4-androsten-3beta,17beta-diol disulfate 1, 1-palmitoleoylglycerophosphocholine, adrenate (22:4n6), and glycodeoxycholate), one amino acid (methionine), and two exogenous metabolites (homostachydrine and 2-methoxyacetaminophen sulfate). Metabolic pathway analysis identified several pathways that might be involved in the disease. CONCLUSION: We identified eight risk and seven protective human serum metabolites associated with lacunar stroke. Isobutyrylcarnitine was positively associated with an increased risk of lacunar stroke. In addition, 3-methyl-2-oxovalerate and aspartate may be involved in the disease pathogenesis through metabolic pathways.


Assuntos
Acidente Vascular Cerebral Lacunar , Acidente Vascular Cerebral , Humanos , Ácido Aspártico , Análise da Randomização Mendeliana , Acidente Vascular Cerebral Lacunar/genética , Acidente Vascular Cerebral/genética , Lipídeos , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
12.
J Surg Res ; 178(2): 949-58, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22694937

RESUMO

BACKGROUND: OX40Ig and CTLA4Ig fusion proteins have been suggested to induce immune tolerance and prevent rejection in allografts. The present study aims to investigate and compare the effects of ex vivo combined OX40Ig and CTLA4Ig lentivirus-mediated gene transfer on the long-term survival of the graft, as well as potential underlying mechanisms. METHODS: We ex vivo transferred Brown Norway rats' superficial groin free flap with lentivirus vectors expressing OX40Ig or CTLA4Ig, or OX40Ig and CTLA4Ig combined, and transplanted the free flaps to Lewis rats. Short-course rapamycin was administered after transfection and transplantation. RT-PCR and Western blot were employed to evaluate expression of OX40Ig and CTLA4Ig. We assessed the survival time of the grafts and the degree of acute graft rejection after indicated treatment. Mixed lymphocyte reaction, flow cytometry, and ELISA were also used to evaluate systemic immune reactions. RESULTS: Ex vivo transfer of OX40Ig or CTLA4Ig lentivirus vectors led to local expression of corresponding mRNA and proteins in the donor flap without affecting other organs of the recipient. The graft survival time was significantly expanded and rejection was markedly attenuated after transfection. Mixed lymphocyte reaction, flow cytometry (CD4(+) and CD8(+) T lymphocyte proportions), and serum ELISA analysis (IL-2, IFN-γ, IL-4, and IL-10) also showed decreased immune response following transfection. Combined OX40Ig and CTLA4Ig transfer exerted superior effect on improving graft survival and preventing graft rejection, inhibiting the immune response and decreasing the production of proinflammatory cytokines, compared with singular transfer of either OX40Ig or CTLA4Ig. CONCLUSION: Combined ex vivo transfer of OX40Ig and CTLA4Ig lentivirus vectors provided superior benefits on long-term survival and restoration of the graft through inhibiting immune response and decreasing the production of proinflammatory cytokines.


Assuntos
Antígenos de Diferenciação/genética , Terapia Genética , Rejeição de Enxerto/prevenção & controle , Imunoconjugados/genética , Abatacepte , Animais , Citocinese , Técnicas de Transferência de Genes , Sobrevivência de Enxerto , Lentivirus/genética , Teste de Cultura Mista de Linfócitos , Masculino , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Retalhos Cirúrgicos , Transplante Homólogo
13.
Org Biomol Chem ; 10(10): 2113-8, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22278640

RESUMO

Functional imidazolium ionic liquids have been developed as a new class of versatile catalysts. C(2)-symmetric imidazolium-tagged bis(oxazoline) ligands were prepared, and the anions of the ligands were altered. The catalysts based on the new ligands and Cu(OAc)(2)·H(2)O were applied in asymmetric Henry reactions between various aldehydes 3 and CH(3)NO(2)4. The catalysts achieved a high level of enantioselectivity; product (R)-5n was attained at 94% ee in MeOH. Moreover, the catalyst could be recycled 6 times without an obvious loss of activity or enantioselectivity. In addition, a theoretical mechanistic study was conducted to explain the origin of the enantioselectivity.


Assuntos
Aldeídos/química , Imidazóis/química , Líquidos Iônicos/química , Oxazóis/química , Catálise , Estereoisomerismo
14.
Chirality ; 24(12): 1092-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23001750

RESUMO

Immobilized Cu(OAc)(2)-bis(oxazolines) via hydrogen bonding by SBA-15 was applied to asymmetric Henry reaction, and good enantioselectivities were obtained (up to 83% ee) between 2-methoxybenzaldehyde and CH(3)NO(2) in isopropyl alcohol (iPrOH). The catalyst could be reused seven times without any obvious loss in enantioselectivity. For the first time, this facile and clean immobilization method is applied to the use of bis(oxazolines) complexes.


Assuntos
Cobre/química , Compostos Organometálicos/química , Benzaldeídos/química , Catálise , Ligação de Hidrogênio , Metano/análogos & derivados , Metano/química , Nitroparafinas/química , Dióxido de Silício/química , Estereoisomerismo
15.
Int J Mol Sci ; 13(7): 8210-8218, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22942699

RESUMO

Through bioassay-guided fractionation of the extracts from the aerial parts of the Chinese herb Hypericum japonicum Thunb. Murray, Isojacareubin (ISJ) was characterized as a potent antibacterial compound against the clinical methicillin-resistant Staphylococcus aureus (MRSA). The broth microdilution assay was used to determine the minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of ISJ alone. The results showed that its MICs/MBCs ranged from 4/16 to 16/64 µg/mL, with the concentrations required to inhibit or kill 50% of the strains (MIC(50)/MBC(50)) at 8/16 µg/mL. Synergistic evaluations of this compound with four conventional antibacterial agents representing different types were performed by the chequerboard and time-kill tests. The chequerboard method showed significant synergy effects when ISJ was combined with Ceftazidime (CAZ), Levofloxacin (LEV) and Ampicillin (AMP), with the values of 50% of the fractional inhibitory concentration indices (FICI(50)) at 0.25, 0.37 and 0.37, respectively. Combined bactericidal activities were also observed in the time-kill dynamic assay. The results showed the ability of ISJ to reduce MRSA viable counts by log(10)CFU/mL at 24 h of incubation at a concentration of 1 × MIC were 1.5 (LEV, additivity), 0.92 (CAZ, indifference) and 0.82 (AMP, indifference), respectively. These in vitro anti-MRSA activities of ISJ alone and its synergy with conventional antibacterial agents demonstrated that ISJ enhanced their efficacy, which is of potential use for single and combinatory therapy of patients infected with MRSA.


Assuntos
Antibacterianos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Xantenos/farmacologia , Ampicilina/farmacologia , Ceftazidima/farmacologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Sinergismo Farmacológico , Genes Bacterianos , Hypericum/química , Concentração Inibidora 50 , Levofloxacino/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Componentes Aéreos da Planta/química
16.
Molecules ; 16(7): 5453-9, 2011 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-21712759

RESUMO

The antibacterial activity of 80% ethanol extracts of 10 medicinal plants collected in Yunnan (Southwest China), was tested against clinical isolates of extended-spectrum ß-lactamase (ESBL)-producing strains. Their MIC values ranged between 1.56-12.50 mg/mL. The most active plant extract was Chelidonium majus L. (MIC = 1.56 mg/mL). Two potent isoquinoline alkaloids, 8-hydroxydihydrosanguinarine and 8-hydroxydihydrochelerythrine, were identified as the major active principles through bioassay-guided fractionation and identification of the active ethyl acetate fraction from C. majus, with minimum MIC/MBC values of 15.63/62.50 mg/mL.


Assuntos
Extratos Vegetais/farmacologia , beta-Lactamases/metabolismo , Alcaloides/farmacologia , Chelidonium/efeitos dos fármacos , Chelidonium/enzimologia , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química
17.
Front Vet Sci ; 8: 661773, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235199

RESUMO

In sheep industry, hypothermia caused by insufficient brown adipose tissue (BAT) deposits is one of the major causes of lamb deaths. Enhancing the formation and function of BAT in neonatal lamb increases thermogenesis and hence reduces economic losses. The aim of the present study was to explore the effect and mechanism of melatonin on sheep brown adipocyte formation and function. Sheep brown adipocyte precursor cells (SBACs) isolated from perirenal BAT were treated with melatonin (1 and 10 nM). The SBACs subjected to melatonin exhibited a decreased proliferation ability, accompanied by down-regulated proliferating cell nuclear antigen, cyclin D1, and CDK4 protein contents in a melatonin dose-dependent manner. Melatonin promoted brown adipocyte formation and induced the expression of brown adipogenic markers, including uncoupling protein 1 and PR domain-containing 16 during differentiation of SBAC. Moreover, the AMP-activated protein kinase α1 (AMPKα1) activity was positively correlated with brown adipocyte formation potential. Importantly, melatonin effectively activated AMPKα1. Furthermore, promotional effects of melatonin were abolished by AMPKα1 knockout, suggesting the involvement of AMPKα1 in this process. Collectively, these results suggested that melatonin enhanced brown adipocyte formation in SBACs in vitro through activation of AMPKα1.

18.
Biosci Rep ; 40(5)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32342982

RESUMO

Cutaneous wound is a soft tissue injury that is difficult to heal during aging. It has been demonstrated that adipose-derived stem cells (ADSCs) and its secreted exosomes exert crucial functions in cutaneous wound healing. The present study aimed to elucidate the mechanism of exosomes derived from ADSCs (ADSC-Exos) containing MALAT1 in wound healing. ADSCs were isolated from human normal subcutaneous adipose tissues and identified by flow cytometry analysis. Exosomes were extracted from ADSC supernatants and MALAT1 expression was determined using qRT-PCR analysis. HaCaT and HDF cells were exposed to hydrogen peroxide (H2O2) for simulating the skin lesion model. Subsequently, CCK-8, flow cytometry, wound healing and transwell assays were employed to validate the role of ADSC-Exos containing MALAT1 in the skin lesion model. Besides, cells were transfected with sh-MALAT1 to verify the protective role of MALAT1 in wound healing. The binding relationship between MALAT1 and miR-124 were measured by dual-luciferase reporter assay. ADSC-Exos promoted cell proliferation, migration, and inhibited cell apoptosis of HaCaT and HDF cells impaired by H2O2. However, the depletion of MALAT1 in ADSC-Exos lose these protective effects on HaCaT and HDF cells. Moreover, miR-124 was identified to be a target of MALAT1. Furthermore, ADSC-Exos containing MALAT1 could mediate H2O2-induced wound healing by targeting miR-124 and activating Wnt/ß-catenin pathway. ADSC-Exos containing MALAT1 play a positive role in cutaneous wound healing possibly via targeting miR-124 through activating the Wnt/ß-catenin pathway, which may provide novel insights into the therapeutic target for cutaneous wound healing.


Assuntos
Exossomos/metabolismo , Fibroblastos/metabolismo , Queratinócitos/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Lesões dos Tecidos Moles/metabolismo , Células-Tronco/metabolismo , Gordura Subcutânea/citologia , Via de Sinalização Wnt , Cicatrização , Apoptose , Movimento Celular , Proliferação de Células , Exossomos/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Células HaCaT , Humanos , Peróxido de Hidrogênio/toxicidade , Queratinócitos/efeitos dos fármacos , Queratinócitos/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Lesões dos Tecidos Moles/genética , Lesões dos Tecidos Moles/patologia
19.
J Integr Plant Biol ; 51(7): 626-37, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19566641

RESUMO

The mature cotton (Gossypium hirsutum L.) fiber is a single cell with a typically thickened secondary cell wall. The aim of this research was to use molecular, spectroscopic and chemical techniques to investigate the possible occurrence of previously overlooked accumulation of phenolics during secondary cell wall formation in cotton fibers. Relative quantitative reverse transcription-polymerase chain reaction analysis showed that GhCAD6 and GhCAD1 were predominantly expressed among seven gene homologs, only GhCAD6 was up-regulated during secondary wall formation in cotton fibers. Phylogenic analysis revealed that GhCAD6 belonged to Class I and was proposed to have a major role in monolignol biosynthesis, and GhCAD1 belonged to Class III and was proposed to have a compensatory mechanism for monolignol biosynthesis. Amino acid sequence comparison showed that the cofactor binding sites of GhCADs were highly conserved with high similarity and identity to bona fide cinnamyl alcohol dehydrogenases. The substrate binding site of GhCAD1 is different from GhCAD6. This difference was confirmed by the different catalytic activities observed with the enzymes. Cell wall auto-fluorescence, Fourier transform infrared spectroscopy (FTIR), high-performance liquid chromatography (HPLC) and chemical analyses confirmed that phenolic compounds were bound to the cell walls of mature cotton fibers. Our findings may suggest a potential for genetic manipulation of cotton fiber properties, which are of central importance to agricultural, cotton processing and textile industries.


Assuntos
Parede Celular/metabolismo , Gossypium/citologia , Gossypium/metabolismo , Fenóis/metabolismo , Propanóis/metabolismo , Oxirredutases do Álcool/química , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/isolamento & purificação , Oxirredutases do Álcool/metabolismo , Sequência de Aminoácidos , Regulação da Expressão Gênica de Plantas , Gossypium/enzimologia , Gossypium/genética , Cinética , Lignina/análise , Dados de Sequência Molecular , Fenóis/análise , Filogenia , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia de Infravermelho com Transformada de Fourier
20.
J Pharm Pharm Sci ; 11(4): 90-4, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19183517

RESUMO

PURPOSE: This study describes the antibacterial effect of extracts and compounds isolated from the aerial part of Chelidonium majus Linn. (Papaveraceae) acting against clinical strains of methicillin-resistant Staphylococcus aureus (MRSA). METHODS: The activities were evaluated by using the macrobroth dilution method and reported as the MICs/MBCs. RESULTS: Bioassay-guided fractionation of the most active extract from the aerial parts (EtOAc) led to the isolation of benzo[c]phenanthridine-type alkaloids 8-hydroxydihydrosanguinarine (hhS), 8-hydroxydihydrochelerythrine (hhC), which were potently active against MRSA strains. CONCLUSIONS: The selective antibacterial activity reported in this paper for 8-hydroxylated benzo[c]phenanthridine-type alkaloids isolated from C.majus opens the possibility that they could be helpful for the developing of new antibacterial agents for treating the infection of MRSA which has created nosocomial problem worldwide.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Papaveraceae/química , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antibacterianos/isolamento & purificação , Quimioterapia Combinada , Testes de Sensibilidade Microbiana , Extratos Vegetais/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico
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