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1.
Plant Cell Environ ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39262278

RESUMO

Plants have developed various resistance mechanisms against herbivorous insects through prolonged coevolution. Plant defence responses can be triggered by specific compounds present in insect saliva. Apyrase, a known enzyme that catalyzes the hydrolysis of adenosine triphosphate (ATP) and adenosine diphosphate (ADP) into adenosine monophosphate (AMP) and inorganic phosphorus, has recently been identified in some herbivorous insects. However, whether insect salivary apyrase induces or inhibits plant responses remains poorly understood. In this study, we identified an apyrase-like protein in the salivary proteome of the fall armyworm, Spodoptera frugiperda, named Sfapyrase. Sfapyrase was primarily expressed in the salivary gland and secreted into plants during insect feeding. Transient expression of Sfapyrase in tobacco and maize enhanced plant resistance and resulted in decreased insect feeding. Knockdown of Sfapyrase through RNA interference led to increased growth and feeding of S. frugiperda. Furthermore, we showed that Sfapyrase activates the jasmonic acid signalling pathway and promotes the synthesis of secondary metabolites, especially benzoxazinoids, thereby enhancing resistance to S. frugiperda. In summary, our findings demonstrated that Sfapyrase acts as a salivary elicitor, inducing maize jasmonic acid defence responses and the production of insect-resistant benzoxazinoids. This study provides valuable insights into plant-insect interactions and offers potential targets for developing innovative insect pest management strategies.

2.
Aging Clin Exp Res ; 36(1): 30, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334839

RESUMO

BACKGROUND: Widespread attention has been given to the detrimental effects of obesity on cognitive function. However, there is no evidence on the connection between low cognitive performance and the WWI (weight-adjusted waist index). This study looked into the connection between poor cognitive performance and the WWI in senior Americans. METHODS: A cross-sectional research study was carried out with information from the NHANES 2011-2014. With multivariate linear regression models, the pertinence between the WWI and low cognitive function in persons older than 60 years was examined. The nonlinear link was described using threshold effect analyses and fitted smoothed curves. Interaction tests and subgroup analysis were also conducted. RESULTS: The study had 2762 individuals in all, and subjects with higher WWI values were at greater risk for low cognitive function. In the completely adjusted model, the WWI was positively connected with low cognitive performance assessed by CERAD W-L (OR = 1.22, 95% CI 1.03-1.45, p = 0.0239), AFT (OR = 1.30, 95% CI 1.09-1.54, p = 0.0029), and DSST (OR = 1.59, 95% CI 1.30-1.94, p < 0.0001). The effect of each subgroup on the positive correlation between the WWI and low cognitive performance was not significant. The WWI and low cognitive performance as determined by CERAD W-L and AFT had a nonlinear connection (log-likelihood ratio < 0.05). CONCLUSION: Among older adults in the United States, the risk of low cognitive performance may be positively related to the WWI.


Assuntos
Cognição , Obesidade , Humanos , Idoso , Estudos Transversais , Inquéritos Nutricionais , Modelos Lineares , Obesidade/epidemiologia
3.
BMC Cardiovasc Disord ; 23(1): 293, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296380

RESUMO

BACKGROUND: In recent years, the incidence of diabetes mellitus has been increasing annually, and cardiovascular complications secondary to diabetes mellitus have become the leading cause of death in diabetic patients. Considering the high incidence of type 2 diabetes (T2DM) combined with cardiovascular disease (CVD), some new hypoglycemic agents with cardiovascular protective effects have attracted extensive attention. However, the specific role of these regimens in ventricular remodeling remains unknown. The purpose of this network meta-analysis was to compare the effects of sodium glucose cotransporter type 2 inhibitor (SGLT-2i), glucagon-like peptide 1 receptor agonist (GLP-1RA) and dipeptidyl peptidase-4 inhibitor (DPP-4i) on ventricular remodeling in patients with T2DM and/or CVD. METHODS: Articles published prior to 24 August 2022 were retrieved in four electronic databases: the Cochrane Library, Embase, PubMed, and Web of Science. This meta-analysis included randomized controlled trials (RCTs) and a small number of cohort studies. The differences in mean changes of left ventricular ultrasonic parameters between the treatment and control groups were compared. RESULTS: A total of 31 RCTs and 4 cohort studies involving 4322 patients were analyzed. GLP-1RA was more significantly associated with improvement in left ventricular end-systolic diameter (LVESD) [MD = -0.38 mm, 95% CI (-0.66, -0.10)] and LV mass index (LVMI) [MD = -1.07 g/m2, 95% CI (-1.71, -0.42)], but significantly decreased e' [MD = -0.43 cm/s 95% CI (-0.81, -0.04)]. DPP-4i was more strongly associated with improvement in e' [MD = 3.82 cm/s, 95% CI (2.92,4.7)] and E/e'[MD = -5.97 95% CI (-10.35, -1.59)], but significantly inhibited LV ejection fraction (LVEF) [MD = -0.89% 95% CI (-1.76, -0.03)]. SGLT-2i significantly improved LVMI [MD = -0.28 g/m2, 95% CI (-0.43, -0.12)] and LV end-diastolic diameter (LVEDD) [MD = -0.72 ml, 95% CI (-1.30, -0.14)] in the overall population, as well as E/e' and SBP in T2DM patients combined with CVD, without showing any negative effect on left ventricular function. CONCLUSION: The results of the network meta-analysis provided high certainty to suggest that SGLT-2i may be more effective in cardiac remodeling compared to GLP-1RA and DPP-4i. While GLP-1RA and DPP-4i may have a tendency to improve cardiac systolic and diastolic function respectively. SGLT-2i is the most recommended drug for reversing ventricular remodeling in this meta-analysis.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Humanos , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hipoglicemiantes/farmacologia , Metanálise em Rede , Inibidores de Proteases/farmacologia , Remodelação Ventricular
4.
Neurobiol Dis ; 134: 104648, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31676238

RESUMO

Accumulation of DNA damage has been detected in the spinal cord of patients as well as in the G93A mouse model of amyotrophic lateral sclerosis (ALS). Wild-type p53-induced phosphatase 1 (Wip1) is a p53-inducible serine/threonine phosphatase that terminates DNA-damage responses via dephosphorylation of DNA-damage response proteins, namely ataxia-telangiectasia mutated (ATM) kinase, checkpoint kinase 2, and p53, thus enhancing cell proliferation. However, the role of Wip1, DNA-damage responses, and their interaction in ALS development remains to be elucidated. Here, we showed that Wip1 expression levels were substantially decreased in ALS motor neurons compared with wild-type controls both in vivo and in vitro. The DNA-damage response was activated in superoxide dismutase 1 (SOD1) G93A-transfected cells. However, increased expression of Wip1 improved cell viability and inhibited the DNA-damage response in mutated SOD1G93A cells. Further studies demonstrated that decreased Wip1 expression reduced cell viability and further activated the DNA-damage response in chronic H2O2-treated NSC34 cells. In contrast, Wip1 promoted cell survival and suppressed DNA damage-induced apoptosis during persistent DNA damage conditions. Over-expression of Wip1 in the central nervous system (CNS) can delay the onset of disease symptoms, extended the survival, decreased MN loss improved motor function and inhibit the DNA-damage response in SOD1 G93A mice. Furthermore, homeodomain-interacting protein kinase 2 (HIPK2) promoted the degradation of Wip1 via the ubiquitin-proteasome system during chronic stress. These findings indicate that persistent accumulation of DNA damage and subsequent chronic activation of the downstream DNA damage-response ATM and p53 pro-apoptotic signaling pathways may trigger neuronal dysfunction and neuronal death in ALS. Wip1 may play a protective role by targeting the DNA-damage response in ALS motor neurons. Importantly, these findings provide a novel direction for therapeutic options for patients with ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Dano ao DNA/fisiologia , Neurônios Motores/metabolismo , Proteína Fosfatase 2C/metabolismo , Transdução de Sinais/fisiologia , Esclerose Lateral Amiotrófica/metabolismo , Animais , Apoptose/fisiologia , Regulação para Baixo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Motores/patologia
5.
Int J Mol Sci ; 17(12)2016 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-27999308

RESUMO

BACKGROUND: Mutations in the Cu/Zn superoxide dismutase (SOD1) gene have been linked to amyotrophic lateral sclerosis (ALS). However, the molecular mechanisms have not been elucidated yet. Homer family protein Homer1b/c is expressed widely in the central nervous system and plays important roles in neurological diseases. In this study, we explored whether Homer1b/c was involved in SOD1 mutation-linked ALS. RESULTS: In vitro studies showed that the SOD1 G93A mutation induced an increase of Homer1b/c expression at both the mRNA and protein levels in NSC34 cells. Knockdown of Homer1b/c expression using its short interfering RNA (siRNA) (si-Homer1) protected SOD1 G93A NSC34 cells from apoptosis. The expressions of Homer1b/c and apoptosis-related protein Bax were also suppressed, while Bcl-2 was increased by lithium and valproic acid (VPA) in SOD1 G93A NSC34 cells. In vivo, both the mRNA and protein levels of Homer1b/c were increased significantly in the lumbar spinal cord in SOD1 G93A transgenic mice compared with wild type (WT) mice. Moreover, lithium and VPA treatment suppressed the expression of Homer1b/c in SOD1 G93A mice. CONCLUSION: The suppression of SOD1 G93A mutation-induced Homer1b/c upregulation protected ALS against neuronal apoptosis, which is a novel mechanism of the neuroprotective effect of lithium and VPA. This study provides new insights into pathogenesis and treatment of ALS.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Proteínas de Arcabouço Homer/biossíntese , Lítio/uso terapêutico , Superóxido Dismutase/genética , Ácido Valproico/uso terapêutico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Apoptose/genética , Linhagem Celular , Predisposição Genética para Doença , Proteínas de Arcabouço Homer/antagonistas & inibidores , Proteínas de Arcabouço Homer/genética , Humanos , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética
6.
Metab Brain Dis ; 30(6): 1387-94, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26231886

RESUMO

Microcephalic osteodysplastic primordial dwarfism type II (MOPD II) is a highly detrimental human autosomal inherited recessive disorder. The hallmark characteristics of this disease are intrauterine and postnatal growth restrictions, with some patients also having cerebrovascular problems such as cerebral aneurysms. The genomic basis behind most clinical features of MOPD II remains largely unclear. The aim of this work was to identify the genetic defects in a Chinese family with MOPD II associated with multiple intracranial aneurysms. The patient had typical MOPD II syndrome, with subarachnoid hemorrhage and multiple intracranial aneurysms. We identified three novel mutations in the PCNT gene, including one single base alteration (9842A>C in exon 45) and two deletions (Del-C in exon 30 and Del-16 in exon 41). The deletions were co-segregated with the affected individual in the family and were not present in the control population. Computer modeling demonstrated that the deletions may cause drastic changes on the secondary and tertiary structures, affecting the hydrophilicity and hydrophobicity of the mutant proteins. In conclusion, we identified two novel mutations in the PCNT gene associated with MOPD II and intracranial aneurysms, and the mutations were expected to alter the stability and functioning of the protein by computer modeling.


Assuntos
Antígenos/genética , Nanismo/genética , Retardo do Crescimento Fetal/genética , Aneurisma Intracraniano/genética , Microcefalia/genética , Mutação/genética , Osteocondrodisplasias/genética , Adolescente , Adulto , Sequência de Aminoácidos , Antígenos/química , Povo Asiático , Criança , Simulação por Computador , Nanismo/complicações , Feminino , Retardo do Crescimento Fetal/etiologia , Deleção de Genes , Transtornos do Crescimento/etiologia , Transtornos do Crescimento/genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Aneurisma Intracraniano/etiologia , Masculino , Microcefalia/complicações , Modelos Moleculares , Dados de Sequência Molecular , Osteocondrodisplasias/complicações , Linhagem , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/genética
7.
Int J Biol Macromol ; 193(Pt A): 8-18, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34673107

RESUMO

Pheromone binding proteins (PBPs), a subfamily of the odorant binding proteins (OBPs), capture and transfer sex pheromones across the sensillum lymph to pheromone receptors and initiate insect courtship and mating. In this study, we functionally characterized ten OBPs from the black chafer, Holotrichia oblita (HoblOBPs), among which six HoblOBPs (HoblOBP2, 4, 5, 8, 9 and 24) were shown to recognize sex pheromones using electroantennography assays (EAG) and in vitro fluorescence competitive binding assays. Insect tropism to sex pheromones was significantly reduced after those genes were knocked down in vivo, e.g. HoblOBP24 RNAi reduced the tropism of H. oblita to methyl glycinate by 34%. Furthermore, molecular docking revealed key residues for the binding of the six HoblOBPs with sex pheromones. And hydrogen bonds and hydrophobic forces were shown to be the main forces in the binding of the six HoblOBPs and their sex pheromone ligands. Our study characterized six H. oblita PBPs and their binding abilities to sex pheromone ligands. The results will improve our understanding on the olfactory mechanisms that H. oblita utilizes to recognize sex pheromones, and will promote the development of novel strategies for controlling H. oblita and other insect pests.


Assuntos
Besouros/metabolismo , Proteínas de Insetos/metabolismo , Receptores Odorantes/metabolismo , Atrativos Sexuais/metabolismo , Animais , Ligantes , Ligação Proteica
8.
DNA Repair (Amst) ; 74: 51-62, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30630676

RESUMO

Increasing evidence indicates that DNA damage and p53 activation play major roles in the pathological process of motor neuron death in amyotrophic lateral sclerosis (ALS). Human SpeedyA1 (Spy1), a member of the Speedy/Ringo family, enhances cell proliferation and promotes tumorigenesis. Further studies have demonstrated that Spy1 promotes cell survival and inhibits DNA damage-induced apoptosis. We showed that the Spy1 expression levels were substantially decreased in ALS motor neurons compared with wild-type controls both in vivo and in vitro by qRT-PCR, western blotting, and Immunoassay tests. In addition, we established that over-expression of human SOD1 mutant G93A led to a decreased expression of Spy1. Furthermore, DNA damage response was activated in SOD1G93A-transfected cells (mSOD1 cells). Moreover, decreased Spy1 expression reduced cell viability and further activated the DNA damage response in mSOD1 cells. In contrast, increased Spy1 expression improved cell viability and inhibited the DNA damage response in mSOD1 cells. These results suggest that Spy1 plays a protective role in ALS motor neurons. Importantly, these findings provide a novel direction for therapeutic options for patients with ALS as well as for trial designs, such as investigating the role of oncogenic proteins in ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA/genética , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Mutação , Superóxido Dismutase-1/genética , Animais , Proteínas de Ciclo Celular/deficiência , Proteínas de Ciclo Celular/genética , Linhagem Celular , Sobrevivência Celular , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos
9.
Chin Med J (Engl) ; 121(14): 1307-12, 2008 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-18713553

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) research has mainly been focused on the therapeutic effect of psychiatric disorders and Parkinson's disease. A few studies have shown that rTMS might protect against delayed neuronal death induced by transient ischemia, enhance long-term potentiation in ischemic conditions and affect regional brain blood flow and metabolism. The aim of this study was to determine the effects of repetitive transcranial magnetic stimulation (rTMS) on adenosine triphosphate (ATP) content and microtubule associated protein-2 (MAP-2) expression in rat brain after middle cerebral artery occlusion (MCAO)/reperfusion. METHODS: To study the effects of different timecourses of rTMS on ATP content and MAP-2 expression, 90 rats were randomly divided into three groups (30 rats in each group). To study the effects of multiple rTMS parameters on ATP content and MAP-2 expression, the rats in each group were further divided into six subgroups (five rats each). The rats were sacrificed at 1-hour, 24-hour and 48-hour intervals after reperfusion, and the brain tissues were collected for the detection of ATP and MAP-2. RESULTS: rTMS could significantly increase ATP content and MAP-2 expression in the left brain following ischemic insult (P < 0.01) and different rTMS parameters had different effects on the ATP level and the MAP-2 expression in the left striatum. A high-frequency rTMS played an important role in MAP-2 expression and ATP preservation. CONCLUSIONS: This study revealed that rTMS induced significant increase of ATP content and MAP-2 expression in the injured area of the brain, suggesting that the regulation of both ATP and MAP-2 may be involved in the biological mechanism of the effect of rTMS on neural recovery. Therefore, rTMS may become a potential adjunctive therapy for ischemic cerebrovascular disease.


Assuntos
Trifosfato de Adenosina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Animais , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Cérebro/metabolismo , Cérebro/patologia , Imuno-Histoquímica , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Fatores de Tempo
10.
Chin Med Sci J ; 20(4): 226-30, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16422248

RESUMO

OBJECTIVE: To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitability and neurofunction after cerebral ischemia-reperfusion injury. METHODS: After determined awake resting motor threshold (MT) and motor evoked potentials (MEPs) of right hindlimbs, 20 Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) reperfusion injury, then rTMS were applied to rTMS group (n=10) at different time, while control group (n=10) received no stimulation. A week later, MT and MEPs were evaluated again, as well as neurological deficits and infarct volume. The effects of rTMS and MCAO reperfusion injury on these parameters were analyzed. RESULTS: After MCAO reperfusion, both MT level and neurological deficit scores increased, distinct focal infarction formed, and latency of MEP elongated. Compared with the control group, the increased extent of MT and neurological scores of rats receiving rTMS were significantly lower (P < 0.05), as well as the infarct volumes reduced significantly (P < 0.05). But MEP was not affected by rTMS obviously. There was a positive linear correlation between postinjury MT and infarct volume (r = 0.64, P < 0.05). CONCLUSION: rTMS may facilitate neurofunction recovery after cerebral ischemia-reperfusion. Postinjury MT could provide prognostic information after MCAO reperfusion injury.


Assuntos
Encéfalo/patologia , Potencial Evocado Motor , Infarto da Artéria Cerebral Média/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Estimulação Magnética Transcraniana , Animais , Comportamento Animal/fisiologia , Membro Posterior/fisiopatologia , Infarto da Artéria Cerebral Média/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia
11.
J Psychiatr Res ; 63: 10-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25748753

RESUMO

Individual structural neuroimaging studies of the corpus callosum (CC) in Alzheimer's disease (AD) and mild cognitive impairment (MCI) with the region of interest (ROI) analysis have yielded inconsistent findings. The aim of this study was to conduct a meta-analysis of structural imaging studies using ROI technique to measure the CC midsagittal area changes in patients with AD or MCI. Databases of PubMed, the Cochrane Library, the ISI Web of Science, and Science Direct from inception to June 2014 were searched with key words "corpus callosum" or "callosal", plus "Alzheimer's disease" or "mild cognitive impairment". Twenty-three studies with 603 patients with AD, 146 with MCI, and 638 healthy controls were included in this meta-analysis. Effect size was used to measure the difference between patients with AD or MCI and healthy controls. Significant callosal atrophy was found in MCI patients with an effect size of -0.36 (95% CI, -0.57 to -0.14; P = 0.001). The degree of the CC atrophy in mild AD was less severe than that in moderate AD with a mean effect size -0.69 (95% CI, -0.89 to -0.49) versus -0.92 (95% CI, -1.16 to -0.69), respectively. Comparing with healthy controls, patients with MCI had atrophy in the anterior portion of the CC (i.e., rostrum and genu). In contrast, patients with AD had atrophy in both anterior and posterior portions (i.e., splenium). These results suggest that callosal atrophy may be related to the degree of cognitive decline in patients with MCI and AD, and it may be used as a biomarker for patients with cognitive deficit even before meeting the criteria for AD.


Assuntos
Doença de Alzheimer/complicações , Disfunção Cognitiva/complicações , Corpo Caloso/patologia , Neuroimagem , Atrofia/etiologia , Atrofia/patologia , Feminino , Humanos , Masculino
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