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1.
Circ Res ; 131(5): 456-472, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35920168

RESUMO

BACKGROUND: Ischemic heart disease is a major global public health challenge, and its functional outcomes remain poor. Lysine crotonylation (Kcr) was recently identified as a post-translational histone modification that robustly indicates active promoters. However, the role of Kcr in myocardial injury is unknown. In this study, we aimed to clarify the pathophysiological significance of Kcr in cardiac injury and explore the underlying mechanism. METHODS: We investigated the dynamic change of both the Kcr sites and protein level in left ventricular tissues at 2 time points following sham or cardiac ischemia-reperfusion injury, followed by liquid chromatography-coupled tandem mass tag mass spectrometry. After validation of the enriched protein Kcr by immunoprecipitation and Western blot, the function and mechanism of specific Kcr sites were further investigated in vitro and in vivo by gain- or loss-of-function mutations targeting Kcr sites of selected proteins. RESULTS: We found that cardiac ischemia-reperfusion injury triggers preferential Kcr of proteins required for cardiomyocyte contractility, including mitochondrial and cytoskeleton proteins, which occurs largely independently of protein-level changes in the same proteins. Those exhibiting Kcr changes were associated not only with disruption of cardiomyocyte mitochondrial, sarcomere architecture, and gap junction but also with cardiomyocyte autophagy and apoptosis. Modulating site-specific Kcr of selected mitochondrial protein IDH3a (isocitrate dehydrogenase 3 [NAD+] alpha) at K199 and cytoskeletal protein TPM1 (tropomyosin alpha-1 chain) at K28/29 or enhancing general Kcr via sodium crotonate provision not only protects cardiomyocyte from apoptosis by inhibiting BNIP3 (Bcl-2 adenovirus E18 19-kDa-interacting protein 3)-mediated mitophagy or cytoskeleton structure rearrangement but also preserves postinjury myocardial function by inhibiting fibrosis and apoptosis. CONCLUSIONS: Our results indicate that Kcr modulation is a key response of cardiomyocytes to ischemia-reperfusion injury and may represent a novel therapeutic target in the context of ischemic heart disease.


Assuntos
Isquemia Miocárdica , Traumatismo por Reperfusão , Humanos , Lisina/metabolismo , Isquemia Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo
2.
BMC Pediatr ; 24(1): 252, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622583

RESUMO

BACKGROUND: Cystic fibrosis is a chronic genetic disease that can affect the function of the respiratory system. Previous reviews of the effects of respiratory muscle training in people with cystic fibrosis are uncertain and do not consider the effect of age on disease progression. This systematic review aims to determine the effectiveness of respiratory muscle training in the clinical outcomes of children and adolescents with cystic fibrosis. METHODS: Up to July 2023, electronic databases and clinical trial registries were searched. Controlled clinical trials comparing respiratory muscle training with sham intervention or no intervention in children and adolescents with cystic fibrosis. The primary outcomes were respiratory muscle strength, respiratory muscle endurance, lung function, and cough. Secondary outcomes included exercise capacity, quality of life and adverse events. Two review authors independently extracted data and assessed study quality using the Cochrane Risk of Bias Tool 2. The certainty of the evidence was assessed according to the GRADE approach. Meta-analyses where possible; otherwise, take a qualitative approach. RESULTS: Six studies with a total of 151 participants met the inclusion criteria for this review. Two of the six included studies were published in abstract form only, limiting the available information. Four studies were parallel studies and two were cross-over designs. There were significant differences in the methods and quality of the methodology included in the studies. The pooled data showed no difference in respiratory muscle strength, lung function, and exercise capacity between the treatment and control groups. However, subgroup analyses suggest that inspiratory muscle training is beneficial in increasing maximal inspiratory pressure, and qualitative analyses suggest that respiratory muscle training may benefit respiratory muscle endurance without any adverse effects. CONCLUSIONS: This systematic review and meta-analysis indicate that although the level of evidence indicating the benefits of respiratory muscle training is low, its clinical significance suggests that we further study the methodological quality to determine the effectiveness of training. TRIAL REGISTRATION: The protocol for this review was recorded in the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42023441829.

3.
Environ Res ; 219: 115004, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36481369

RESUMO

Aiming for treating decentralized domestic wastewater in rural China, this study evaluates the effects of ceramsite size and structure, and water recirculation parameters, upon the performance of recirculating biofilter (RBF). RBF shows stable capability of chemical oxygen demand (COD) remediation and ammonia nitrification. In addition, the microbial flora and structures of the various layers in the system are analyzed via high-throughput sequencing in order to study the microbial diversity. The results indicate that while the ceramic particle size has no significant influence on the COD remediation capacity, the ceramics with smaller particle sizes exhibit better ammonia nitrogen (NH4+-N) removal ability, with a first-order linear relationship between the influent ammonia nitrogen load and the effluent NH4+-N concentration in RBF (R2 > 0.64). An increased hydraulic load and intermittent operation are shown to deteriorate the water quality with respect to NH4+-N, while an increased recirculation ratio increases the removal rate of NH4+-N from the effluent. Further, the water distribution time has a stronger effect upon the NH4+-N concentration in the effluent than does the recirculation ratio. Moreover, the microbial structure of the multi-layer recirculating trickle biofilter varies significantly during the process. The results indicate that a high recirculation ratio, long water distribution time, and multi-layer structure will be beneficial for improving the pollutant treatment capacity of RBF.


Assuntos
Amônia , Esgotos , Reatores Biológicos , Águas Residuárias , Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos
4.
BMC Cardiovasc Disord ; 22(1): 461, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329408

RESUMO

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) are commonly used in regenerative medicine. However, it is not clear whether transplantation of BMSCs can improve cardiac function of the X-Linked Muscular Dystrophy Mice (mdx) and how to detect it. We aimed to investigate the role of speckle tracking echocardiography (STE) in detecting cardiac function of the BMSCs-transplanted mdx in comparison with the untreated mdx. METHODS: The experimental mice were divided into the BMSCs-transplanted mdx, untreated mdx, and control mice groups (n = 6 per group). The BMSCs were transplanted via tail vein injections into a subset of mdx at 20 weeks of age. After four weeks, the cardiac functional parameters of all the mice in the 3 groups were analyzed by echocardiography. Then, all the mice were sacrificed, and the cardiac tissues were harvested and analyzed by immunofluorescence. The serum biochemical parameters were also analyzed to determine the beneficial effects of BMSCs transplantation. RESULTS: Traditional echocardiography parameters did not show statistically significant differences after BMSCs transplantation for the three groups of mice. In comparison with the control group, mdx showed significantly lower left ventricular (LV) STE parameters in both the long-axis and short-axis LV images (P < 0.05). However, BMSCs-transplanted mdx showed improvements in several STE parameters including significant increases in a few STE parameters (P < 0.05). Immunofluorescence staining of the myocardium tissues showed statistically significant differences between the mdx and the control mice (P < 0.05), and the mdx transplanted with BMSCs demonstrated significantly improvement compared with the untreated mdx (P < 0.05). CONCLUSION: This study demonstrated that the early reduction in the LV systolic and diastolic function in the mdx were accurately detected by STE. Furthermore, our study demonstrated that the transplantation of BMSCs significantly improved myocardial function in the mdx.


Assuntos
Medula Óssea , Distrofia Muscular de Duchenne , Camundongos , Animais , Infusões Intravenosas , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/diagnóstico , Ecocardiografia/métodos , Miocárdio
5.
J Bone Miner Metab ; 38(5): 670-677, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32415375

RESUMO

INTRODUCTION: The periosteum has a bilayered structure that surrounds cortical bone. The outer layer is rich in connective tissue and fibroblasts, while the inner layer in contact with the cortical surface of the bone predominantly consists of osteoblasts and osteoblast progenitors. The identification of cell-specific surface markers of the bilayered structure of the periosteum is important for the purpose of tissue regeneration. MATERIALS AND METHODS: We investigated the expression of the discoidin domain tyrosine kinase receptor DDR2, fibroblast specific protein-1 (FSP-1) and alkaline phosphatase (ALP) in the periosteum of cortical bone by immunohistochemistry. Osteogenic differentiation was compared between DDR2- and FSP-1-expressing cells flow-sorted from the periosteum. RESULTS: We showed that DDR2 predominantly labeled osteogenic cells residing in the inner layer of the periosteum and that Pearson's coefficient of colocalization indicated a significant correlation with the expression of ALP. The mineralization of DDR2-expressing osteogenic cells isolated from the periosteum was significantly induced. In contrast, FSP-1 predominantly labeled the outer layer of periosteal fibroblasts, and Pearson's coefficient of colocalization indicated that FSP-1 was poorly correlated with the expression of DDR2 and ALP. FSP-1-expressing periosteal fibroblasts did not exhibit osteogenic differentiation for the induction of bone mineralization. CONCLUSION: DDR2 is a novel potential cell surface marker for identifying and isolating osteoblasts and osteoblast progenitors within the periosteum that can be used for musculoskeletal regenerative therapies.


Assuntos
Receptores com Domínio Discoidina/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Periósteo/citologia , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores/metabolismo , Calcificação Fisiológica , Diferenciação Celular , Camundongos Endogâmicos C57BL , Osteogênese , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo
6.
J Clin Lab Anal ; 34(9): e23402, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32557798

RESUMO

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy. The human G6PD gene is highly polymorphic, and over 200 mutations have been identified, many of which are associated with hemolytic anemia. Here, we analyzed the clinical genetics data of a Chinese girl with favism who developed acute hemolytic anemia after fava bean ingestion. METHODS: The clinical genetics data of the proband who developed acute hemolytic anemia were collected and analyzed, and G6PD gene exons were sequenced in the proband and her family. RESULTS: We reported for the first time a novel G6PD gene variant in a Chinese girl, which we named "G6PD Wuhan." This variant is localized exon 3 of the G6PD gene at genomic position 141G > C, that is a change from p.Lys47 to Asn. The bioinformatics analysis and protein modeling study indicated this variant may have negative effects on the enzyme activity of G6PD. CONCLUSIONS: Our results indicated that favism in the proband was caused by this novel heterozygous variant (c.141G > C) in G6PD. The variant in G6PD has implications for genetic counseling and could provide insights into the functional roles of G6PD mutations.


Assuntos
Povo Asiático/genética , Favismo/genética , Favismo/patologia , Glucosefosfato Desidrogenase/genética , Mutação , Pré-Escolar , Feminino , Humanos , Prognóstico
7.
Circ J ; 83(2): 295-303, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30518738

RESUMO

BACKGROUND: It has been suggested that protein directly activated by cAMP (Epac), one of the downstream signaling molecules of ß-adrenergic receptor (ß-AR), may be an effective target for the treatment of arrhythmia. However, there have been no reports on the anti-arrhythmic effects or cardiac side-effects of Epac1 inhibitors in vivo. Methods and Results: In this study, the roles of Epac1 in the development of atrial and ventricular arrhythmias are examined. In addition, we examined the usefulness of CE3F4, an Epac1-selective inhibitor, in the treatment of the arrhythmias in mice. In Epac1 knockout (Epac1-KO) mice, the duration of atrial fibrillation (AF) was shorter than in wild-type mice. In calsequestrin2 knockout mice, Epac1 deficiency resulted in a reduction of ventricular arrhythmia. In both atrial and ventricular myocytes, sarcoplasmic reticulum (SR) Ca2+ leak, a major trigger of arrhythmias, and spontaneous SR Ca2+ release (SCR) were attenuated in Epac1-KO mice. Consistently, CE3F4 treatment significantly prevented AF and ventricular arrhythmia in mice. In addition, the SR Ca2+ leak and SCR were significantly inhibited by CE3F4 treatment in both atrial and ventricular myocytes. Importantly, cardiac function was not significantly affected by a dosage of CE3F4 sufficient to exert anti-arrhythmic effects. CONCLUSIONS: These findings indicated that Epac1 is involved in the development of atrial and ventricular arrhythmias. CE3F4, an Epac1-selective inhibitor, prevented atrial and ventricular arrhythmias in mice.


Assuntos
Fibrilação Atrial/prevenção & controle , AMP Cíclico/antagonistas & inibidores , Fibrilação Ventricular/prevenção & controle , Animais , Fibrilação Atrial/etiologia , Cálcio/metabolismo , AMP Cíclico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/antagonistas & inibidores , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Camundongos , Camundongos Knockout , Quinolinas/uso terapêutico , Retículo Sarcoplasmático/metabolismo , Fibrilação Ventricular/etiologia
8.
Minerva Pediatr ; 71(4): 358-361, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26354415

RESUMO

BACKGROUND: To investigate the effect of frontal muscle aponeurosis flap suspension surgery for severe congenital ptosis in children. METHODS: Recent results of 30 cases (45 eyes) of children with severe congenital ptosis were evaluated and follow-up observation was conducted. RESULTS: One week after the surgery, the success rate was 97.7% and it was 95.5% after three months. CONCLUSIONS: The suspension of frontal muscle aponeurosis should be the first choice for children with severe congenital ptosis for its simplicity, safety and fewer complications.


Assuntos
Blefaroptose/cirurgia , Retalhos Cirúrgicos , Aponeurose , Blefaroptose/congênito , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Índice de Gravidade de Doença
9.
Pflugers Arch ; 470(6): 923-935, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29453615

RESUMO

Sympathetic activation causes clinically important arrhythmias including atrial fibrillation (AF) and ventricular tachyarrhythmia. Although the usefulness of ß-adrenergic receptor blockade therapy is widely accepted, its multiple critical side effects often prevent its initiation or continuation. The aim of this study is to determine the advantages of vidarabine, an adenylyl cyclase (AC)-targeted anti-sympathetic agent, as an alternative treatment for arrhythmia. We found that vidarabine, which we identified as a cardiac AC inhibitor, consistently shortens AF duration and reduces the incidence of sympathetic activation-induced ventricular arrhythmias. In atrial and ventricular myocytes, vidarabine inhibits adrenergic receptor stimulation-induced RyR2 phosphorylation, sarcoplasmic reticulum (SR) Ca2+ leakage, and spontaneous Ca2+ release from SR, the last of which has been considered as a potential arrhythmogenic trigger. Moreover, vidarabine also inhibits sympathetic activation-induced reactive oxygen species (ROS) production in cardiac myocytes. The pivotal role of vidarabine's inhibitory effect on ROS production with regard to its anti-arrhythmic property has also been implied in animal studies. In addition, as expected, vidarabine exerts an inhibitory effect on AC function, which is more potent in the heart than elsewhere. Indexes of cardiac function including ejection fraction and heart rate were not affected by a dosage of vidarabine sufficient to exert an anti-arrhythmic effect. These findings suggest that vidarabine inhibits catecholamine-induced AF or ventricular arrhythmia without deteriorating cardiac function in mice.


Assuntos
Inibidores de Adenilil Ciclases/farmacologia , Antiarrítmicos/farmacologia , Antivirais/farmacologia , Arritmias Cardíacas/tratamento farmacológico , Coração/efeitos dos fármacos , Vidarabina/farmacologia , Inibidores de Adenilil Ciclases/efeitos adversos , Inibidores de Adenilil Ciclases/uso terapêutico , Animais , Antiarrítmicos/efeitos adversos , Antiarrítmicos/uso terapêutico , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Arritmias Cardíacas/etiologia , Sinalização do Cálcio , Catecolaminas/toxicidade , Herpesviridae/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Vidarabina/efeitos adversos , Vidarabina/uso terapêutico
10.
J Food Sci Technol ; 55(5): 1816-1822, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29666534

RESUMO

Drip loss of fresh-cut watermelon has become a concern for both producers and consumers. The effect of visible light exposure on the drip loss of fresh-cut watermelon was evaluated. Visible light treatments of 3000 and 10 Lux were applied to fresh-cut watermelon at 4 °C during the shelf life for 5 days, with light exposure of 150 Lux as the control. The drip loss of the fresh-cut watermelon at 3000 Lux was 74.8% of that at 150 Lux on the fifth day, and the moisture evaporation at 3000 Lux was 1.89 times that at 150 Lux. Moreover, the light exposure of 3000 Lux reduced the activity of polygalacturonase, which is a key hydrolase related to cell wall degradation. The cell wall degradation ratio of the fresh-cut watermelon at 3000 Lux was 81.7% of that at 150 Lux on the fifth day. Overall, light exposure of 3000 Lux reduced drip loss by accelerating moisture evaporation in fresh-cut watermelon, as well as by reducing the activity of polygalacturonase and the ratio of cell wall degradation. Hence, exposing the fresh-cut watermelon to visible light of 3000 Lux during the shelf life was a feasible way of reducing drip loss.

11.
J Mol Cell Cardiol ; 108: 170-180, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28629760

RESUMO

Pro-inflammatory cytokines are released in septic shock and impair cardiac function via the Jak-STAT pathway. It is well known that sympathetic stimulation leads to coupling of the ß-adrenergic receptor/Gs/adenylyl cyclase, a membrane-bound enzyme that catalyzes the conversion of ATP to cAMP, thereby stimulating protein kinase A (PKA) and ultimately compensating for cardiac dysfunction. The mechanism of such compensation by catecholamine has been traditionally understood as PKA-mediated enforcement of cardiac contractility. We hypothesized that exchange protein activated by cyclic AMP (Epac), a new target of cAMP signaling that functions independently of protein kinase A, also plays a key role in protection against acute stresses or changes in hemodynamic overload. Lipopolysaccharide injection induced cytokine release and severe cardiac dysfunction in mouse. In mouse overexpressing Epac1 in the heart, however, the magnitude of such dysfunction was significantly smaller. Epac1 overexpression inhibited the Jak-STAT pathway, as indicated by decreased phosphorylation of STAT3 and increased SOCS3 expression, with subsequent inhibition of iNOS expression. In cultured cardiomyocytes treated with isoproterenol or forskolin, the increase of SOCS3 expression was blunted when Epac1 or PKCα was silenced with siRNA. Activation of the cAMP/Epac/PKCα pathway protected the heart against cytokine-induced cardiac dysfunction, suggesting a new role of catecholamine signaling in compensating for cardiac dysfunction in heart failure. Epac1 and its downstream pathways may be novel targets for treating cardiac dysfunction in endotoxemia.


Assuntos
Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/genética , Janus Quinases/metabolismo , Miócitos Cardíacos/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Disfunção Ventricular/etiologia , Disfunção Ventricular/metabolismo , Animais , Biomarcadores , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Catecolaminas/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Testes de Função Cardíaca , Humanos , Lipopolissacarídeos/efeitos adversos , Camundongos , Camundongos Transgênicos , Modelos Biológicos , Óxido Nítrico Sintase Tipo II/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Disfunção Ventricular/tratamento farmacológico , Disfunção Ventricular/fisiopatologia
13.
Biochem Biophys Res Commun ; 475(1): 1-7, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27117748

RESUMO

Type 5 adenylyl cyclase (AC5) plays an important role in the development of chronic catecholamine stress-induced heart failure and arrhythmia in mice. Epac (exchange protein activated by cAMP), which is directly activated by cAMP independent of protein kinase A, has been recently identified as a novel mediator of cAMP signaling in the heart. However, the role of Epac in AC5-mediated cardiac dysfunction and arrhythmias remains poorly understood. We therefore generated AC5 transgenic mice (AC5TG) with selective disruption of the Epac1 gene (AC5TG-Epac1KO), and compared their phenotypes with those of AC5TG after chronic isoproterenol (ISO) infusion. Decreased cardiac function as well as increased susceptibility to pacing-induced atrial fibrillation (AF) in response to ISO were significantly attenuated in AC5TG-Epac1KO mice, compared to AC5TG mice. Increased cardiac apoptosis and cardiac fibrosis were also concomitantly attenuated in AC5TG-Epac1KO mice compared to AC5TG mice. These findings indicate that Epac1 plays an important role in AC5-mediated cardiac dysfunction and AF susceptibility.


Assuntos
Adenilil Ciclases/metabolismo , Fibrilação Atrial/patologia , Catecolaminas/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Miocárdio/patologia , Animais , Apoptose , Fibrilação Atrial/etiologia , Fibrilação Atrial/genética , Fibrilação Atrial/metabolismo , Fibrose , Fatores de Troca do Nucleotídeo Guanina/genética , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Fisiológico
14.
Circ J ; 80(12): 2496-2505, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27818454

RESUMO

BACKGROUND: In heart failure patients, chronic hyperactivation of sympathetic signaling is known to exacerbate cardiac dysfunction. In this study, the cardioprotective effect of vidarabine, an anti-herpes virus agent, which we identified as a cardiac adenylyl cyclase inhibitor, in dogs with pacing-induced dilated cardiomyopathy (DCM) was evaluated. In addition, the adverse effects of vidarabine on basal cardiac function was compared to those of the ß-blocker, carvedilol.Methods and Results:Vidarabine and carvedilol attenuated the development of pacing-induced systolic dysfunction significantly and with equal effectiveness. Both agents also inhibited the development of cardiac apoptosis and fibrosis and reduced the Na+-Ca2+exchanger-1 protein level in the heart. Importantly, carvedilol significantly enlarged the left ventricle and atrium; vidarabine, in contrast, did not. Vidarabine-treated dogs maintained cardiac response to ß-AR stimulation better than carvedilol-treated dogs did. CONCLUSIONS: Vidarabine may protect against pacing-induced DCM with less suppression of basal cardiac function than carvedilol in a dog model. (Circ J 2016; 80: 2496-2505).


Assuntos
Antivirais/farmacologia , Cardiomiopatia Dilatada , Insuficiência Cardíaca , Vidarabina/farmacologia , Animais , Carbazóis/farmacologia , Cardiomiopatia Dilatada/tratamento farmacológico , Cardiomiopatia Dilatada/fisiopatologia , Carvedilol , Modelos Animais de Doenças , Cães , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Herpesviridae , Humanos , Propanolaminas/farmacologia
15.
Biochem Biophys Res Commun ; 458(3): 531-535, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25677623

RESUMO

Myocardial ß-adrenergic receptor (ß-AR) ß1- and ß2-subtypes are highly homologous, but play opposite roles in cardiac apoptosis and heart failure, as do cardiac adenylyl cyclase (AC) subtypes 5 (AC5) and 6 (AC6): ß1-AR and AC5 promote cardiac remodeling, while ß2-AR and AC6 activate cell survival pathways. However, the mechanisms involved remain poorly understood. We hypothesized that AC5 is coupled preferentially to ß1-AR rather than ß2-AR, and we examined this idea by means of pharmacological and genetic approaches. We found that selective inhibition of AC5 with 2'5'-dideoxyadenosine significantly suppressed cAMP accumulation and cardiac apoptosis induced by selective ß1-AR stimulation, but had no effect on cAMP accumulation and cardiac apoptosis in response to selective ß2-AR stimulation. The results of selective stimulation of ß1-AR and ß2-AR in neonatal cardiac myocytes prepared from wild-type and AC5-knockout mice were also consistent with the idea that ß1-AR selectively couples with AC5. We believe these results are helpful for understanding the mechanisms underlying the different roles of AR subtypes in healthy and diseased hearts.


Assuntos
Adenilil Ciclases/metabolismo , Miócitos Cardíacos/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Adenilil Ciclases/genética , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , AMP Cíclico/metabolismo , Camundongos , Camundongos Knockout , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos
16.
J Immunol ; 190(12): 6051-8, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23677469

RESUMO

Despite various suspected causes, ranging from endocrine and genetic to infectious and immunological aspects, the molecular mechanisms of miscarriage still remain enigmatic. This work provides evidence that downregulation of 11ß-hydroxysteroid dehydrogenase (HSD) type 2, the key enzyme inactivating glucocorticoid activities, insults the pregnant inflammatory milieu by inhibiting the biosynthesis of lipoxin A4 (LXA4), a metabolite of arachidonic acid, leading to an early loss of the pregnancy. Both LXA4 and its biosynthetic enzymes were found to be decreased in women with spontaneous miscarriages and in the murine miscarriage model. Replenishing LXA4 reversed LPS-induced miscarriages in mouse models, whereas blocking LXA4 signaling resulted in miscarriages in the pregnant mice. The protective effect of LXA4 might be explained by LXA4's role in regulating uterine and placental inflammatory factors and mast cells. The underlying molecular mechanism involved miscarriage-inducing infections or stresses that downregulate the expression of 11ß-HSD2, but not 11ß-HSD1, resulting in increases in glucocorticoid activity and decreases in LXA4. Together, these findings suggest that the stress/glucocorticoid/LXA4 axis might be a common pathway through which miscarriages occur.


Assuntos
11-beta-Hidroxiesteroide Desidrogenases/metabolismo , Aborto Espontâneo/fisiopatologia , Glucocorticoides/metabolismo , Lipoxinas/metabolismo , Estresse Fisiológico/fisiologia , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
17.
J Immunol ; 191(6): 3453-61, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23956429

RESUMO

Mechanisms by which tumor cells metastasize to distant organs still remain enigmatic. Immune cells have been assumed to be the root of metastasis by their fusing with tumor cells. This fusion theory, although interpreting tumor metastasis analogically and intriguingly, is arguable to date. We show in this study an alternative explanation by immune cell-derived microparticles (MPs). Upon stimulation by PMA or tumor cell-derived supernatants, immune cells released membrane-based MPs, which were taken up by H22 tumor cells, leading to tumor cell migration in vitro and metastasis in vivo. The underlying molecular basis was involved in integrin α(M)ß2 (CD11b/CD18), which could be effectively relayed from stimulated innate immune cells to MPs, then to tumor cells. Blocking either CD11b or CD18 led to significant decreases in MP-mediated tumor cell metastasis. This MP-mediated transfer of immune phenotype to tumor cells might also occur in vivo. These findings suggest that tumor cells may usurp innate immune cell phenotypes via MP pathway for their metastasis, providing new insight into tumor metastatic mechanism.


Assuntos
Carcinoma Hepatocelular/patologia , Micropartículas Derivadas de Células/metabolismo , Imunidade Inata , Neoplasias Hepáticas/patologia , Antígeno de Macrófago 1/metabolismo , Invasividade Neoplásica/patologia , Animais , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Micropartículas Derivadas de Células/imunologia , Modelos Animais de Doenças , Citometria de Fluxo , Imunidade Inata/imunologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal , Microscopia Eletrônica de Transmissão
18.
J Physiol ; 592(24): 5461-75, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25344550

RESUMO

The predominant isoform of ß-adrenoceptor (ß-AR) in skeletal muscle is ß2-AR and that in the cardiac muscle is ß1-AR. We have reported that Epac1 (exchange protein directly activated by cAMP 1), a new protein kinase A-independent cAMP sensor, does not affect cardiac hypertrophy in response to pressure overload or chronic isoproterenol (isoprenaline) infusion. However, the role of Epac1 in skeletal muscle hypertrophy remains poorly understood. We thus examined the effect of disruption of Epac1, the major Epac isoform in skeletal muscle, on masseter muscle hypertrophy induced by chronic ß2-AR stimulation with clenbuterol (CB) in Epac1-null mice (Epac1KO). The masseter muscle weight/tibial length ratio was similar in wild-type (WT) and Epac1KO at baseline and was significantly increased in WT after CB infusion, but this increase was suppressed in Epac1KO. CB treatment significantly increased the proportion of myosin heavy chain (MHC) IIb at the expense of that of MHC IId/x in both WT and Epac1KO, indicating that Epac1 did not mediate the CB-induced MHC isoform transition towards the faster isoform. The mechanism of suppression of CB-mediated hypertrophy in Epac1KO is considered to involve decreased activation of Akt signalling. In addition, CB-induced histone deacetylase 4 (HDAC4) phosphorylation on serine 246 mediated by calmodulin kinase II (CaMKII), which plays a role in skeletal muscle hypertrophy, was suppressed in Epac1KO. Our findings suggest that Epac1 plays a role in ß2-AR-mediated masseter muscle hypertrophy, probably through activation of both Akt signalling and CaMKII/HDAC4 signalling.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Músculo Masseter/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Histona Desacetilases/metabolismo , Hipertrofia/metabolismo , Músculo Masseter/efeitos dos fármacos , Músculo Masseter/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Cadeias Pesadas de Miosina/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
19.
Front Bioeng Biotechnol ; 12: 1400912, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720881

RESUMO

The rehabilitation robot can assist hemiplegic patients to complete the training program effectively, but it only focuses on helping the patient's training process and requires the rehabilitation therapists to manually adjust the training parameters according to the patient's condition. Therefore, there is an urgent need for intelligent training prescription research of rehabilitation robots to promote the clinical applications. This study proposed a decision support system for the training of upper limb rehabilitation robot based on hybrid reasoning with rule-based reasoning (RBR) and case-based reasoning (CBR). The expert knowledge base of this system is established base on 10 professional rehabilitation therapists from three different rehabilitation departments in Shanghai who are enriched with experiences in using desktop-based upper limb rehabilitation robot. The rule-based reasoning is chosen to construct the cycle plan inference model, which develops a 21-day training plan for the patients. The case base consists of historical case data from 54 stroke patients who underwent rehabilitation training with a desktop-based upper limb rehabilitation robot. The case-based reasoning, combined with a Random Forest optimized algorithm, was constructed to adjust the training parameters for the patients in real-time. The system recommended a rehabilitation training program with an average accuracy of 91.5%, an average AUC value of 0.924, an average recall rate of 88.7%, and an average F1 score of 90.1%. The application of this system in rehabilitation robot would be useful for therapists.

20.
Technol Health Care ; 32(4): 2293-2306, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38759031

RESUMO

BACKGROUND: Rehabilitation assessment is a critical component of rehabilitation treatment. OBJECTIVE: This study focuses on a comprehensive analysis of patients' movement performance using the upper limb rehabilitation robot. It quantitatively assessed patients' motor control ability and constructed an intelligent grading model of functional impairments. These findings contribute to a deeper understanding of patients' motor ability and provide valuable insights for personalized rehabilitation interventions. METHODS: Patients at different Brunnstrom stages underwent rehabilitation training using the upper limb rehabilitation robot, and data on the distal movement positions of the patients' upper limbs were collected. A total of 22 assessment metrics related to movement efficiency, smoothness, and accuracy were extracted. The performance of these assessment metrics was measured using the Mann-Whitney U test and Pearson correlation analysis. Due to the issue of imbalanced sample categories, data augmentation was performed using the Synthetic Minority Over-sampling Technique (SMOTE) algorithm based on weighted sampling, and an intelligent grading model of functional impairment based on the Extreme Gradient Boosting Tree (XGBoost) algorithm was constructed. RESULTS: Sixteen assessment metrics were screened. These metrics were effectively normalized to their maximum values, enabling the derivation of quantitative assessment scores for motor control ability across the three dimensions through a weighted fusion approach. Notably, when applied to the data-enhanced dataset, the intelligent grading model exhibited remarkable improvement, achieving an accuracy rate exceeding 0.98. Moreover, significant enhancements were observed in terms of precision, recall, and f1-score. CONCLUSION: The research findings demonstrate that this study enables the quantitative assessment of patients' motor control ability and intelligent grading of functional impairments, thereby contributing to the efficiency enhancement of clinical rehabilitation assessment. Moreover, this method resolves the issues associated with the subjectivity and prolonged periods of traditional rehabilitation assessment methods.


Assuntos
Extremidade Superior , Humanos , Extremidade Superior/fisiopatologia , Extremidade Superior/fisiologia , Fenômenos Biomecânicos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Robótica/métodos , Algoritmos , Idoso , Movimento/fisiologia
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