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1.
J Nanobiotechnology ; 22(1): 178, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38614985

RESUMO

BACKGROUND: Clearance of apoptotic cells by efferocytosis is crucial for prevention of atherosclerosis progress, and impaired efferocytosis contributes to the aggravated atherosclerosis. RESULTS: In this study, we found that diabetic ApoE-/- mice showed aggravated atherosclerosis as hyperglycemia damaged the efferocytosis capacity at least partially due to decreased expression of Mer tyrosine kinase (MerTK) on macrophages. To locally restore MerTK in the macrophages in the plaque, hybrid membrane nanovesicles (HMNVs) were thus developed. Briefly, cell membrane from MerTK overexpressing RAW264.7 cell and transferrin receptor (TfR) overexpressing HEK293T cell were mixed with DOPE polymers to produce nanovesicles designated as HMNVs. HMNVs could fuse with the recipient cell membrane and thus increased MerTK in diabetic macrophages, which in turn restored the efferocytosis capacity. Upon intravenous administration into diabetic ApoE-/- mice, superparamagnetic iron oxide nanoparticles (SMN) decorated HMNVs accumulated at the aorta site significantly under magnetic navigation, where the recipient macrophages cleared the apoptotic cells efficiently and thus decreased the inflammation. CONCLUSIONS:  Our study indicates that MerTK decrease in macrophages contributes to the aggravated atherosclerosis in diabetic ApoE-/- mice and regional restoration of MerTK in macrophages of the plaque via HMNVs could be a promising therapeutic approach.


Assuntos
Aterosclerose , Diabetes Mellitus , Humanos , Animais , Camundongos , Eferocitose , Células HEK293 , Membrana Celular , Proteínas Tirosina Quinases , Apolipoproteínas E/genética , Nanopartículas Magnéticas de Óxido de Ferro
2.
Lipids Health Dis ; 23(1): 115, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643148

RESUMO

BACKGROUND: The triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio and triglyceride-glucose (TyG) index are novel indexes for insulin resistance (IR). We aimed to evaluate associations of TG/HDL-C and TyG with arterial stiffness risk. METHODS: We enrolled 1979 participants from the Rural Chinese Cohort Study, examining arterial stiffness by brachial-ankle pulse wave velocity (baPWV). Logistic and linear regression models were employed to calculate effect estimates. For meta-analysis, we searched relevant articles from PubMed, Embase and Web of Science up to August 26, 2023. The fixed-effects or random-effects models were used to calculate the pooled estimates. We evaluated dose-response associations using restricted cubic splines. RESULTS: For cross-sectional studies, the adjusted ORs (95%CIs) for arterial stiffness were 1.12 (1.01-1.23) and 1.78 (1.38-2.30) for per 1 unit increment in TG/HDL-C and TyG. In the meta-analysis, the pooled ORs (95% CIs) were 1.26 (1.14-1.39) and 1.57 (1.36-1.82) for per 1 unit increment of TG/HDL-C and TyG. Additionally, both TG/HDL-C and TyG were positively related to PWV, with ß of 0.09 (95% CI 0.04-0.14) and 0.57 (95% CI 0.35-0.78) m/s. We also found linear associations of TG/HDL-C and TyG with arterial stiffness risk. CONCLUSIONS: High TG/HDL-C and TyG were related to increased arterial stiffness risk, indicating TG/HDL-C and TyG may be convincing predictors of arterial stiffness.


Assuntos
Resistência à Insulina , Rigidez Vascular , Humanos , Glucose , Triglicerídeos , Estudos de Coortes , Índice Tornozelo-Braço , Rigidez Vascular/fisiologia , HDL-Colesterol , Estudos Transversais , Análise de Onda de Pulso , Resistência à Insulina/genética , Glicemia , Biomarcadores
3.
Child Care Health Dev ; 50(2): e13237, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38410046

RESUMO

PURPOSE: This meta-analysis evaluated the relationship between overweight/obesity and depressive disorders in children and adolescents. METHODS: We examined the databases of PubMed, Embase and Web of Science for pertinent observational studies released up until 20 February 2022. The pooled relative risks (RRs) and 95% confidence intervals (CIs) of obesity and overweight with depressive disorder were calculated by means of random-effects models. The Newcastle-Ottawa Quality Assessment Scale and Agency for Healthcare Research and Quality scale were adopted to evaluate the study quality. RESULTS: Finally, for this meta-analysis, we evaluated 22 observational publications covering 175 135 participants (5 cohort study articles, 1 case-control study article and 16 cross-sectional study articles). A significant positive association was found between obesity and the risk of depression (RR 1.32, 95% CI 1.09-1.60, I2 = 79.90%, Pheterogeneity < 0.001) and in the association between obesity and depressive symptoms (RR 1.16, 95% CI: 1.00-1.35, I2 = 25.0%, Pheterogeneity = 0.247). On sensitivity analysis, the pooled RRs remained robust. Subgroup analysis indicated that obese children and teenagers in western countries were more prone to depression. CONCLUSION: Evidence from this meta-analysis, based on observational studies, supported the idea that obese children and adolescents are more likely to experience depression and depressive symptoms.


Assuntos
Transtorno Depressivo , Obesidade Infantil , Adolescente , Humanos , Criança , Sobrepeso , Obesidade Infantil/complicações , Obesidade Infantil/epidemiologia , Estudos de Coortes , Estudos Transversais , Estudos de Casos e Controles , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/etiologia , Estudos Observacionais como Assunto
4.
J Urban Health ; 100(4): 788-801, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37580544

RESUMO

While noise pollution from transportation has become an important public health problem, the relationships between different sources of traffic noise and cardiovascular diseases (CVDs) remain inconclusive. A comprehensive meta-analysis was therefore conducted to quantitatively assess the effects of long-term exposure to road traffic, railway, and aircraft noise on CVDs and relevant subtypes. We systematically retrieved PubMed, Embase, and Web of Science for articles published before April 4, 2022. Summary relative risks (RRs) and 95% confidence intervals (CIs) were estimated by the fixed- or random-effects models. In total, 23 articles were included in our meta-analysis. The risk of CVDs increased by 2% (RR 1.020, 95% CI 1.006-1.035) and 1.6% (RR 1.016, 95% CI 1.000-1.032) for every 10 dB increment of road traffic and aircraft noise. For CVD subtypes, the risk increased by 3.4% (1.034, 1.026-1.043) for stroke and 5% (1.050, 1.006-1.096) for heart failure with each 10 dB increment of road traffic noise; the risk of atrial fibrillation increased by 1.1% (1.011, 1.002-1.021) with each 10 dB increment of railway noise; and the risk increased by 1% (1.010, 1.003-1.017) for myocardial infarction, 2.7% (1.027, 1.004-1.050) for atrial fibrillation, and 2.3% (1.023, 1.016-1.030) for heart failure with each 10 dB increment in aircraft noise. Further, effects from road traffic, railway, and aircraft noise all followed positive linear trends with CVDs. Long-term exposure to traffic noise is positively related to the incidence risk of cardiovascular events, especially road traffic noise which significantly increases the risk of CVDs, stroke, and heart failure.


Assuntos
Fibrilação Atrial , Doenças Cardiovasculares , Insuficiência Cardíaca , Ruído dos Transportes , Acidente Vascular Cerebral , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Ruído dos Transportes/efeitos adversos , Fibrilação Atrial/complicações , Insuficiência Cardíaca/complicações , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Exposição Ambiental/efeitos adversos
5.
Scand J Med Sci Sports ; 33(7): 1168-1176, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36843531

RESUMO

OBJECTIVES: Sedentary behavior (SB) and physical inactivity have been associated with an increased risk of all-cause mortality. Evidence in China is scarce, and it is unclear whether physical activity (PA) attenuates or even eliminates the harmful effects of prolonged SB in the Chinese population. METHODS: We conducted a prospective cohort study of 17 084 Chinese adults. PA and sitting time (ST) were assessed using the IPAQ. Cox proportional hazards models were used to estimate the risk of PA and ST with all-cause mortality. Interaction plots were used to visualize the interaction effects. RESULTS: During a median follow-up of 6.01 years, a total of 1106 deaths occurred. PA level was inversely associated with the incidence of all-cause mortality, while ST showed a detrimental association (all ptrend < 0.05). In the stratified analysis, ST was associated with all-cause mortality in the low PA, while the association was attenuated in the moderate PA group: the HRs (95% CI) comparing ST of 4-8, 8-11, and ≥11 to <4 h/day were 1.15 (0.73-1.81), 1.55 (0.92-2.59), and 2.70 (1.52-4.80), respectively. In the high PA group, no significant association was found across all ST levels. In the joint analysis, compared with the high PA and ST <4 h/day, the harmful effect was found only in the combined low PA and moderate PA groups with ST ≥11 h/day (HR:2.71, 95% CI:1.69-4.35). In addition, a significant interaction association was found. CONCLUSION: Our study, based on a prospective cohort, suggests that the detrimental effect of ST on all-cause mortality is attenuated or eliminated by high PA levels in the Chinese population.


Assuntos
Exercício Físico , Comportamento Sedentário , Adulto , Humanos , Estudos Prospectivos , Modelos de Riscos Proporcionais , China/epidemiologia
6.
Environ Geochem Health ; 45(8): 6745-6759, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378736

RESUMO

We sought to explore the association between heavy metal exposure and coronary heart disease (CHD) based on data from the US National Health and Nutrition Examination Survey (NHANES, 2003-2018). In the analyses, participants were all aged > 20 and had participated in heavy metal sub-tests with valid CHD status. The Mann-Kendall test was employed to assess the trends in heavy metals' exposure and the trends in CHD prevalence over 16 years. Spearman's rank correlation coefficient and a logistics regression (LR) model were used to estimate the association between heavy metals and CHD prevalence. 42,749 participants were included in our analyses, 1802 of whom had a CHD diagnosis. Total arsenic, dimethylarsonic acid, monomethylarsonic acid, barium, cadmium, lead, and antimony in urine, and cadmium, lead, and total mercury in blood all showed a substantial decreasing exposure level tendency over the 16 years (all Pfor trend < 0.05). CHD prevalence varied from 3.53 to 5.23% between 2003 and 2018. The correlation between 15 heavy metals and CHD ranges from - 0.238 to 0.910. There was also a significant positive correlation between total arsenic, monomethylarsonic acid, and thallium in urine and CHD by data release cycles (all P < 0.05). The cesium in urine showed a negative correlation with CHD (P < 0.05). We found that exposure trends of total arsenic, dimethylarsonic acid, monomethylarsonic acid, barium, cadmium, lead, and antimony in urine and blood decreased. CHD prevalence fluctuated, however. Moreover, total arsenic, monomethylarsonic acid, and thallium in urine all showed positive relationships with CHD, while cesium in urine showed a negative relationship with CHD.


Assuntos
Arsênio , Doença das Coronárias , Metais Pesados , Adulto , Humanos , Cádmio/análise , Inquéritos Nutricionais , Arsênio/toxicidade , Arsênio/análise , Antimônio/análise , Bário/análise , Tálio/análise , Prevalência , Exposição Ambiental/análise , Metais Pesados/análise , Césio/análise , Doença das Coronárias/induzido quimicamente , Doença das Coronárias/epidemiologia
7.
Crit Rev Food Sci Nutr ; : 1-13, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36148848

RESUMO

Several epidemiological studies have suggested that flavonoid intake is associated with a decreased risk of cardiometabolic disease. However, the results remained inconsistent and there is no dose-response meta-analysis for specific outcomes. We conducted a meta-analysis to synthesize the knowledge about their associations and to explore their dose-response relationships. We comprehensively searched the PubMed, Embase, and Web of Science databases for prospective cohort studies published up to December 1, 2021. Summary relative risks (RR) and 95% confidence intervals (CI) were pooled for the association between flavonoid intake and cardiometabolic disease. Evaluations of linear or nonlinear dose-response were presented by restricted cubic splines. We identified 47 articles, including 1,346 676 participants and 127,507 cases in this meta-analysis. The summary of RR per 500 mg/d increase in flavonoid intake was 0.93 (95% CI 0.88-0.98) for cardiovascular disease, 0.89 (95% CI 0.84-0.94) for diabetes, and 0.97 (95% CI 0.94-0.99) for hypertension, respectively. We also found a linearity dose-response association between total flavonoid intake and cardiovascular disease (p nonlinearity = 0.541), and diabetes (p nonlinearity = 0.077). Our finding based on quantitative data suggested that a higher level of flavonoid intake is beneficial for the prevention of cardiometabolic diseases.

8.
Br J Nutr ; 128(6): 1029-1036, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34632975

RESUMO

To investigate the association between the Metabolic Score for Visceral Fat (METS-VF) and risk of type 2 diabetes mellitus (T2DM) and compare the predictive value of the METS-VF for T2DM incidence with other obesity indices in Chinese people. A total of 12 237 non-T2DM participants aged over 18 years from the Rural Chinese Cohort Study of 2007-2008 were included at baseline and followed up during 2013-2014. The cox proportional hazards regression was used to calculate hazard ratios (HR) and 95 % CI for the association between baseline METS-VF and T2DM risk. Restricted cubic splines were used to model the association between METS-VF and T2DM risk. Area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the ability of METS-VF to predict T2DM incidence. During a median follow-up of 6·01 (95 % CI 5·09, 6·06) years, 837 cases developed T2DM. After adjusting for potential confounding factors, the adjusted HR for the highest v. lowest METS-VF quartile was 5·97 (95 % CI 4·28, 8·32), with a per 1-sd increase in METS-VF positively associated with T2DM risk. Positive associations were also found in the sensitivity and subgroup analyses, respectively. A significant nonlinear dose-response association was observed between METS-VF and T2DM risk for all participants (Pnonlinearity = 0·0347). Finally, the AUC value of METS-VF for predicting T2DM was largest among six indices. The METS-VF may be a reliable and applicable predictor of T2DM incidence in Chinese people regardless of sex, age or BMI.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Humanos , Adulto , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Síndrome Metabólica/epidemiologia , Estudos de Coortes , Gordura Intra-Abdominal/metabolismo , Obesidade/metabolismo , Fatores de Risco , China/epidemiologia
9.
J Nanobiotechnology ; 20(1): 463, 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309712

RESUMO

BACKGROUND: Exosome mediated mRNA delivery is a promising strategy for the treatment of multiple diseases. However, the low yield of exosomes is a bottleneck for clinical translation. In this study, we boosted exosome production via simultaneously reducing the expression of genes inhibiting exosome biogenesis and supplementing the culture medium with red cell membrane components. RESULTS: Among the candidate genes, knocking down of Rab4 was identified to have the highest efficacy in promoting exosome biogenesis while without any obvious cytotoxicity. Additionally, supplementing red cell membrane particles (RCMPs) in the culture medium further promoted exosome production. Combination of Rab4 knockdown and RCMP supplement increased exosome yield up to 14-fold. As a proof-of-concept study, low-density lipoprotein receptor (Ldlr) mRNA was forced expressed in the exosome donor cells and passively encapsulated into the exosomes during biogenesis with this strategy. Though exosome production per cell increased, the booster strategy didn't alter the loading efficiency of therapeutic Ldlr mRNA per exosome. Consistently, the therapeutic exosomes derived by the strategy alleviated liver steatosis and atherosclerosis in Ldlr-/- mice, similar as the exosomes produced by routine methods. CONCLUSIONS: Together, the proposed exosome booster strategy conquers the low yield bottleneck to some extent and would certainly facilitate the clinical translation of exosomes.


Assuntos
Exossomos , Camundongos , Animais , Exossomos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Nano Lett ; 21(20): 8563-8570, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34647460

RESUMO

Extracellular vesicles (EV)-based delivery of therapeutic mRNAs is challenged by the low loading efficiency. In this study, we designed a DNA aptamer consisting of two parts: the single strand part recognized the AUG region of target mRNA, preventing mRNA from translation and ribosome assembly; and the double strand part containing the elements recognized by the CD9-ZF (zinc finger) motifs, sorting DNA aptamer-mRNA complex into CD9-ZF engineered EVs. In vitro and in vivo studies revealed that the system could efficiently load functional mRNAs to the EVs. Furthermore, adipose specific delivery of loaded Pgc1α mRNA via the strategy could efficiently induce white adipocyte browning. Similarly, delivery of interleukin-10 (Il-10) mRNA via the strategy had potent anti-inflammatory effect in inflammatory bowel disease (IBD) mouse model. Together, our study has proposed an efficient strategy to load therapeutic mRNAs of interest into EVs, which could be used as a promising strategy for gene therapy.


Assuntos
Aptâmeros de Nucleotídeos , Vesículas Extracelulares , Animais , Movimento Celular , Modelos Animais de Doenças , Camundongos , RNA Mensageiro/genética
11.
Opt Express ; 29(11): 16695-16709, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154227

RESUMO

Bound states in the continuum (BICs) are trapped or guided modes with frequencies in radiation continua. They are associated with high-quality-factor resonances that give rise to strong local field enhancement and rapid variations in scattering spectra, and have found many valuable applications. A guided mode of an optical waveguide can also be a BIC, if there is a lateral structure supporting compatible waves propagating in the lateral direction; i.e., there is a channel for lateral leakage. A BIC is typically destroyed (becomes a resonant or a leaky mode) if the structure is slightly perturbed, but some BICs are robust with respect to a large family of perturbations. In this paper, we show (analytically and numerically) that a typical BIC in optical waveguides with a left-right mirror symmetry and a single lateral leakage channel is robust with respect to any structural perturbation that preserves the left-right mirror symmetry. Our study improves the theoretical understanding on BICs and can be useful when applications of BICs in optical waveguides are explored.

12.
Cell Biol Int ; 45(4): 785-794, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33325083

RESUMO

Neuroinflammation mediated by microglia has been identified as vital pathogenesis in Parkinson's disease (PD). This study aimed to investigate the role and potential regulatory mechanism of microRNA-330 in the lipopolysaccharide (LPS)-induced chronic neuroinflammatory model. Primary microglia chronic inflammation model and PD animal model were established by LPS treatment. Bulged microRNA-330 sponges containing six microRNA binding sites were constructed and delivered by plasmid or recombinant adeno-associated virus (rAAV2)/5-green fluorescent protein (GFP) vector. The expression levels of microRNA-330 were assessed by a quantitative real-time polymerase chain reaction. Primary microglia polarization was determined by flow cytometry; meanwhile, dopamine and pro-(anti-)inflammatory cytokines were measured by enzyme-linked immunosorbent assay. Expression levels of GFAP, lba1, inducible nitric oxide synthase (iNOS), Arg1, SHIP1, cytoplasmic, and nuclear factor-κB (NF-κB) were analyzed by Western blot. The behavioral deficit was determined by the rotarod test. The expression of microRNA-330 increased in the first 4 days and reached a plateau subsequently after LPS treatment. The sponges-mediated repression effect on M1 polarization was gradually enhanced with time. Treatment of miR-330 sponges increased the SHIP1 and Arg1 expression, and decreased the translocation of NF-κB and iNOS expression, suggesting the repression of inflammation. In the LPS-induced PD mice, administration of rAAV-sponge-GFP suppressed activation of microglia, downregulated proinflammatory cytokines, resumed the secretion of dopamine, rescued the dopaminergic neurons, and alleviated motor dysfunction. Our results demonstrated that microRNA-330 sponges could sustainably suppress LPS-induced polarization of microglia both in vivo and in vitro probably by negatively regulating NF-κB activity via target SHIP1 in microglia, which might be a promising neuroprotective strategy in neurological diseases, such as PD.


Assuntos
MicroRNAs/metabolismo , NF-kappa B/metabolismo , Doença de Parkinson/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Microglia
13.
J Nanobiotechnology ; 19(1): 402, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863187

RESUMO

BACKGROUND: Efficient and topical delivery of drugs is essential for maximized efficacy and minimized toxicity. In this study, we aimed to design an exosome-based drug delivery platform endowed with the ability of escaping from phagocytosis at non-target organs and controllably releasing drugs at targeted location. RESULTS: The swtichable stealth coat CP05-TK-mPEG was synthesized and anchored onto exosomes through the interaction between peptide CP05 and exosomal surface marker CD63. Chlorin e6 (Ce6) was loaded into exosomes by direct incubation. Controllable removal of PEG could be achieved by breaking thioketal (TK) through reactive oxygen species (ROS), which was produced by Ce6 under ultrasound irradiation. The whole platform was called SmartExo. The stealth effects were analyzed in RAW264.7 cells and C57BL/6 mice via tracing the exosomes. To confirm the efficacy of the engineered smart exosomes, Bone morphogenetic protein 7 (Bmp7) mRNA was encapsulated into exosomes by transfection of overexpressing plasmid, followed by stealth coating, with the exosomes designated as SmartExo@Bmp7. Therapeutic advantages of SmartExo@Bmp7 were proved by targeted delivering Bmp7 mRNA to omental adipose tissue (OAT) of obese C57BL/6 mice for browning induction. SmartExo platform was successfully constructed without changing the basic characteristics of exosomes. The engineered exosomes effectively escaped from the phagocytosis by RAW264.7 and non-target organs. In addition, the SmartExo could be uptaken locally on-demand by ultrasound mediated removal of the stealth coat. Compared with control exosomes, SmartExo@Bmp7 effectively delivered Bmp7 mRNA into OAT upon ultrasound irradiation, and induced OAT browning, as evidenced by the histology of OAT and increased expression of uncoupling protein 1 (Ucp1). CONCLUSIONS: The proposed SmartExo-based delivery platform, which minimizes side effects and maximizing drug efficacy, offers a novel safe and efficient approach for targeted drug delivery. As a proof, the SmartExo@Bmp7 induced local white adipose tissue browning, and it would be a promising strategy for anti-obesity therapy.


Assuntos
Tecido Adiposo Branco , Proteína Morfogenética Óssea 7 , Sistemas de Liberação de Medicamentos/métodos , RNA Mensageiro , Terapia por Ultrassom , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Administração Tópica , Animais , Bioengenharia , Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/farmacocinética , Proteína Morfogenética Óssea 7/farmacologia , Exossomos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/farmacocinética , RNA Mensageiro/farmacologia
14.
J Physiol ; 598(15): 3173-3186, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32415785

RESUMO

KEY POINTS: Rapid alterations of gravitational stress during high-performance aircraft push-pull manoeuvres induce dramatic shifts in volume and pressure within the circulation system, which may result in loss of consciousness due to the rapid and significant reduction in cerebral perfusion. There are still no specific and effective countermeasures so far. We found that lower body negative pressure (LBNP), applied prior to and during -Gz and released at the subsequent transition to +Gz, could effectively counteract gravitational haemodynamic stress induced by a simulated push-pull manoeuvre and improve cerebral diastolic perfusion in human subjects. We developed a LBNP strategy that effectively protects cerebral perfusion at rapid -Gz to +Gz transitions via improving cerebral blood flow and blood pressure during push-pull manoeuvres and highlight the importance of the timing of the intervention. Our findings provide a systemic link of integrated responses between the peripheral and cerebral haemodynamic changes during push-pull manoeuvres. ABSTRACT: The acute negative (-Gz) to positive (+Gz) gravity stress during high-performance aircraft push-pull manoeuvres dramatically reduces transient cerebral perfusion, which may lead to loss of vision or even consciousness. The aim of this study was to explore a specific and effective counteractive strategy. Twenty-three healthy young male volunteers (age 21 ± 1 year) were subjected to tilting-simulated push-pull manoeuvres. Lower body negative pressure (LBNP) of -40 mmHg was applied prior to and during -Gz stress (-0.50 or -0.87 Gz) and released at the subsequent transition to +1.00 Gz stress. Beat-to-beat cerebral and systemic haemodynamics were continuously recorded during the simulated push-pull manoeuvre in LBNP bouts and corresponding control bouts. During the rapid gravitational transition from -Gz to +Gz, the mean cerebral blood flow velocity decreased significantly in control bouts, while it increased in LBNP bouts (control vs. LBNP bouts, -6.6 ± 4.6 vs. 5.1 ± 6.8 cm s-1 for -0.50 Gz, and -7.4 ± 4.8 vs. 3.4 ± 4.6 cm s-1 for -0.87 Gz, P < 0.01), which was attributed mainly to the elevation of diastolic flow. The LBNP bouts showed much smaller reduction of mean arterial blood pressure at the brain level than control bouts (control bouts vs. LBNP bouts, -38 ± 12 vs. -23 ± 10 mmHg for -0.50 to +1.00 Gz, and -62 ± 16 vs. -43 ± 11 mmHg for -0.87 to +1.00 Gz, P < 0.01). LBNP applied at -Gz and released at subsequent +Gz had biphasic counteractive effects against the gravitational responses to the push-pull manoeuvre. These data demonstrate that this LBNP strategy could effectively protect cerebral perfusion with dominant improvement of diastolic flow during push-pull manoeuvres.


Assuntos
Aviação , Pressão Negativa da Região Corporal Inferior , Adulto , Pressão Sanguínea , Encéfalo , Circulação Cerebrovascular , Gravitação , Humanos , Masculino , Perfusão , Adulto Jovem
15.
Biochem Biophys Res Commun ; 532(1): 60-67, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-32828538

RESUMO

Chemotherapy related cardiotoxicity is now becoming one of the biggest hurdles for the prognosis of cancer patients. Therapeutically delivering protective small RNAs holds promise for the cardiotoxicity prevention and therapy. However, heart is intrinsically refractory to the nanoparticle-mediated drug delivery. In this study, we found that the exosome-mediated miRNA delivery into the heart could be significantly augmented with the aid of ultrasound targeted microbubble destruction (UTMD). Moreover, we found that UTMD assisted exosomal miR-21 delivery into the heart significantly decreased the cell death, and restored the cardiac function in a doxorubicin induced cardiotoxicity mouse model. Our study here not only provides a promising strategy to protect the heart from the chemotherapy related cardiotoxicity, but also sheds light on gene therapy of other heart diseases.


Assuntos
Cardiotônicos/administração & dosagem , Cardiotoxicidade/prevenção & controle , MicroRNAs/administração & dosagem , Animais , Antibióticos Antineoplásicos/toxicidade , Apoptose , Cardiotoxicidade/patologia , Cardiotoxicidade/fisiopatologia , Morte Celular , Modelos Animais de Doenças , Doxorrubicina/toxicidade , Sistemas de Liberação de Medicamentos , Ecocardiografia Doppler de Pulso , Exossomos , Testes de Função Cardíaca , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Microbolhas , Ultrassom
16.
BMC Cardiovasc Disord ; 20(1): 355, 2020 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-32741356

RESUMO

BACKGROUND: Patients with chronic kidney disease (CKD) experience abnormality of intracardiac blood flow status during early-stages of disease. Left ventricular energy loss (EL) derived from vector flow mapping (VFM) represents fluid energy lost as heat in left ventricle and had been used to detect intracardiac blood flow efficiency. We aimed to evaluate the left ventricular EL in stage 1-3 CKD patients, and explored whether hypertension, a main cardiovascular risk, deteriorate the abnormality of intracardiac blood flow status. METHODS: Transthoracic echocardiography was performed in 41 controls and 48 patients with stages 1-3 CKD. CKD patients consisted a subgroup with no hypertension, a subgroup with well-controlled hypertension and a subgroup with poorly controlled hypertension. The EL were calculated in the left ventricle using VFM analysis from the apical 3-chamber view. Furthermore, the correlation and stepwise multiple regression analysis were used to explore the potential independent predictors of left ventricular EL. RESULTS: Compared with controls, stage 1-3 CKD patients showed increased left ventricular EL during total diastole, late diastole, total systole, isovolumic contraction and ejection. CKD patients with poorly controlled hypertension had higher left ventricular EL compared to the other CKD subgroups. Additionally, the ratio of mitral early filling wave peak velocity and early mitral annular peak velocity on septal side, mitral early filling wave peak velocity, and left ventricular mass index were independent predictors of the diastolic EL; whereas systolic blood pressure and left ventricular mass index were independent predictors of the systolic EL. CONCLUSIONS: Left ventricular EL was a useful echocardiographic parameter to evaluate the impaired intracardiac blood flow efficiency in patients with stages 1-3 CKD. Hypertension was a crucial contributor for intracardiac blood flow abnormality. This study might provide valuable clinical data to discern cardiac dysfunction and reduce the cardiovascular risk in early-stage CKD.


Assuntos
Ecocardiografia Doppler em Cores , Metabolismo Energético , Cardiopatias/diagnóstico por imagem , Insuficiência Renal Crônica/complicações , Função Ventricular Esquerda , Adulto , Pressão Sanguínea , Estudos de Casos e Controles , Estudos Transversais , Transferência de Energia , Feminino , Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Temperatura Alta , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Reprodutibilidade dos Testes
17.
Nano Lett ; 19(1): 19-28, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30517011

RESUMO

In vitro and in vivo delivery of RNAs of interest holds promise for gene therapy. Recently, exosomes are considered as a kind of rational vehicle for RNA delivery, especially miRNA and/or siRNA, while the loading efficiency is limited. In this study, we engineered the exosomes for RNA loading by constructing a fusion protein in which the exosomal membrane protein CD9 was fused with RNA binding protein, while the RNA of interest either natively harbors or is engineered to have the elements for the binding. By proof-of-principle experiments, we here fused CD9 with HuR, an RNA binding protein interacting with miR-155 with a relatively high affinity. In the exosome packaging cells, the fused CD9-HuR successfully enriched miR-155 into exosomes when miR-155 was excessively expressed. Moreover, miR-155 encapsulated in the exosomes in turn could be efficiently delivered into the recipient cells and recognized the endogenous targets. In addition, we also revealed that the CD9-HuR exosomes could enrich the functional miRNA inhibitor or CRISPR/dCas9 when the RNAs were engineered to have the AU rich elements. Taken together, we here have established a novel strategy for enhanced RNA cargo encapsulation into engineered exosomes, which in turn functions in the recipient cells.


Assuntos
Proteína Semelhante a ELAV 1/química , Exossomos/química , MicroRNAs/química , Tetraspanina 29/química , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Proteína Semelhante a ELAV 1/genética , Exossomos/genética , Técnicas de Transferência de Genes , Humanos , Camundongos , MicroRNAs/genética , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Tetraspanina 29/genética
18.
Am J Physiol Heart Circ Physiol ; 317(6): H1376-H1387, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31702970

RESUMO

There is still lack of a simple, accurate, and noninvasive method for rat aortic pulse wave velocity (PWV) measurement, especially the transit distance cannot be accurately measured. Thus, we aimed to derive an equation for aortic transit distance as a function of the nose-to-rump length (L) and to test the hypothesis that aortic PWV measured by new equation combined with Doppler ultrasound (the "equation method") may have stronger correlation with invasive measurements than traditional "body surface method." Two-hundred male Sprague-Dawley (SD) rats (age ranged 5-24 wk) were included in protocol 1, and the aortic transit distances were measured postmortem. In protocol 2, heart-femoral PWV and carotid-femoral PWV were measured by equation method (hfPWVE, cfPWVE) and also by traditional body surface method (hfPWVS, cfPWVS) in another 30 young and 28 old rats. These measurements were then validated against invasively measured hfPWVI and cfPWVI from the same animal. Protocol 1 showed that the heart-femoral transit distance could be calculated by 0.6086 × L - 1.6523, and the carotid-femoral transit distance by 0.4614 × L + 1.8335. In protocol 2, in young rats, the Pearson r between hfPWVE, cfPWVE, hfPWVS, and cfPWVS and their corresponding invasive measurement were 0.8962, 0.8509, 0.8387, and 0.7828, respectively (all P < 0.0001). In the old group, the results were 0.8718, 0.7999, 0.8330, and 0.7112, respectively (all P < 0.0001). The hfPWVE and cfPWVE showed better agreement with hfPWVI and cfPWVI and lower intra- and interobserver variability compared with hfPWVS and cfPWVS in both groups. These findings demonstrate that this novel methodology provides a simple and reliable method for rat noninvasive aortic PWV measurement.NEW & NOTEWORTHY First, when measuring aortic PWV in SD rat models, the heart-femoral transit distance can be estimated by 0.6086 × L - 1.6523, and the carotid-femoral distance transit distance can be estimated by 0.4614 × L + 1.8335, where L (in mm) is nose-to-rump length. Second, this novel methodology for aortic PWV measurement was validated with a closer correlation with the invasive measurements than traditional approach in young and old rats. Third, this study provides a simple and reliable method for rat noninvasive aortic PWV measurement.


Assuntos
Aorta/fisiologia , Velocidade da Onda de Pulso Carótido-Femoral/métodos , Ultrassonografia Doppler/métodos , Envelhecimento/fisiologia , Animais , Aorta/diagnóstico por imagem , Aorta/crescimento & desenvolvimento , Velocidade da Onda de Pulso Carótido-Femoral/normas , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Ultrassonografia Doppler/normas
19.
Rheumatol Int ; 39(10): 1711-1721, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31375887

RESUMO

The objective of this study is to investigate the relative impact of rheumatoid arthritis (RA) and other factors on arterial stiffness of different regions assessed by regional pulse wave velocity (PWV). Seventy-two patients with RA and 55 strictly matched healthy controls were included. Doppler ultrasound was used to measure the PWV of heart-carotid (hcPWV), heart-femoral (hfPWV), brachial-radial (brPWV), femoral-ankle (faPWV) and carotid-femoral segments (cfPWV) in all subjects. The reproducibility of regional PWV measurement was evaluated in 30 random RA patients. In RA patients, the hfPWV and cfPWV were significantly higher than that in controls (P = 0.0006, P = 0.0001, respectively), and the hcPWV, brPWV and faPWV only showed an increase trend without significance. The mean increase magnitude of hfPWV (17.5%) and cfPWV (18.5%) were greater than brPWV (7.2%) and faPWV (1.7%) in RA patients. The association between RA and both hfPWV, cfPWV remained significant after adjustments for other confounders (P < 0.001). However, the association between RA and brPWV (P = 0.199), faPWV (P = 0.599) was not significant. In addition, age and systolic blood pressure were also significant independent factors associated with hfPWV and cfPWV. The reproducibility analysis showed that hfPWV and cfPWV measurements had lower coefficient of variation than others. The stiffness of different arterial regions is not equally affected by RA. The stiffening of aorta is more preferentially associated with RA than that of the peripheral arteries in extremities. The discrepant stiffening between aorta and peripheral arteries may provide a new insight into the pathogenesis of cardiovascular and microvascular dysfunction frequently occurred in RA.


Assuntos
Doenças da Aorta/etiologia , Artérias/fisiopatologia , Artrite Reumatoide/complicações , Doença Arterial Periférica/etiologia , Rigidez Vascular , Adulto , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/fisiopatologia , Artérias/diagnóstico por imagem , Artrite Reumatoide/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Valor Preditivo dos Testes , Análise de Onda de Pulso , Fatores de Risco , Ultrassonografia Doppler
20.
Echocardiography ; 36(3): 567-576, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30677176

RESUMO

BACKGROUND: Intra-ventricular blood flow dynamics is considered as an important component of left ventricular (LV) function assessment. The purpose of this study was to evaluate the LV diastolic function in chronic kidney disease (CKD) with different degrees of LV diastolic dysfunction (LVDD) by using flow energetic parameters. METHODS: In this study, a total of 96 cases were recruited, including 58 CKD patients and 38 healthy controls. CKD patients were divided into 2 groups according to LVDD severity, named as DD1 and DD2. Vector flow-mapping (VFM) analysis was executed to calculate left ventricle average energy loss (EL) during early filling phase (E-EL_ave), atrial filling phase (A-EL_ave), diastole phase (D-EL_ave), and ejection phase (S-EL_ave). Moreover, the average vortex circulation during early filling phase (E-cir_ave) and atrial filling phase (A-cir_ave) was also assessed in the apical three-chamber view. The rate of average EL during early filling and atrial filling was expressed as E/A-EL. RESULT: Compared to the control group, A-EL_ave, S-EL_ave, and A-cir_ave in the DD1 group were higher (P < 0.05), and all parameters were obviously higher in the DD2 group (P < 0.05). In the control group and the DD2 subgroup, the E-EL_ave value was significantly higher than A-EL_ave value, which was opposite to the DD1 group. As diastolic dysfunction worsened, E-EL_ave and D-EL_ave risen gradually (P < 0.05), and A-EL_ave and S-EL_ave were slightly elevated with no significance. There were significant correlations between LV diastolic function and flow energetic parameters. Stepwise multiple regression analysis revealed that various LV function parameters could be regarded as independent predictors of average diastolic EL (all P < 0.01). CONCLUSIONS: For CKD patient with LVDD and LVEF > 50%, effective LV filling and systolic ejection with optimized energy consumption have been impaired. As a new flow-derived index, EL can quantitatively evaluate LV diastolic function in terms of blood fluid dynamics in CKD with various LVDD.


Assuntos
Ecocardiografia , Hemodinâmica/fisiologia , Insuficiência Renal Crônica/complicações , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos de Casos e Controles , Diástole/fisiologia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/fisiopatologia , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia
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