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1.
J Virol ; 97(3): e0174322, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36877044

RESUMO

Type III interferons (IFNLs) have critical roles in the host's innate immune system, also serving as the first line against pathogenic infections of mucosal surfaces. In mammals, several IFNLs have been reported; however, only limited data on the repertoire of IFNLs in avian species is available. Previous studies showed only one member in chicken (chIFNL3). Herein, we identified a novel chicken IFNL for the first time, termed chIFNL3a, which contains 354 bp, and encodes 118 amino acids. The predicted protein is 57.1% amino acid identity with chIFNL. Genetic, evolutionary, and sequence analyses indicated that the new open reading frame (ORF) groups with type III chicken IFNs represent a novel splice variant. Compared to IFNs from different species, the new ORF is clustered within the type III IFNs group. Further study showed that chIFNL3a could activate a panel of IFN-regulated genes and function mediated by the IFNL receptor, and chIFNL3a markedly inhibited the replication of Newcastle disease virus (NDV) and influenza virus in vitro. These data collectively shed light on the repertoire of IFNs in avian species and provide useful information that further elucidate the interaction of the chIFNLs and viral infection of poultry. IMPORTANCE Interferons (IFNs) are critical soluble factors in the immune system, and are composed of 3 types (I, II, and III) that utilize different receptor complexes (IFN-αR1/IFN-αR2, IFN-γR1/IFN-γR2, and IFN-λR1/IL-10R2, respectively). Herein, we identified IFNL from the genomic sequences of chicken and termed it chIFNL3a, located on chromosome 7 of chicken. Phylogenetically clustered with all known types of chicken IFNs, the finding of this IFN is considered a type III IFN. To further evaluate the biological properties of chIFNL3a, the target protein was prepared by the baculovirus expression system (BES), which could markedly inhibit the replication of NDV and influenza viruses. In this study, we uncovered a new interferon lambda splice variant of chicken, termed chIFNL3a, which could inhibit viral replication in cells. Importantly, these novel findings may extend to other viruses, offering a new direction for therapeutic interventions.


Assuntos
Galinhas , Orthomyxoviridae , Animais , Interferon lambda , Antivirais/farmacologia , Interferons/metabolismo , Orthomyxoviridae/metabolismo , Vírus da Doença de Newcastle/metabolismo , Mamíferos
2.
J Virol ; 97(12): e0137623, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37991368

RESUMO

IMPORTANCE: Rotavirus (RV) is an important zoonosis virus, which can cause severe diarrhea and extra-intestinal infection. To date, some proteins or carbohydrates have been shown to participate in the attachment or internalization of RV, including HGBAs, Hsc70, and integrins. This study attempted to indicate whether there were other proteins that would participate in the entry of RV; thus, the RV VP4-interacting proteins were identified by proximity labeling. After analysis and verification, it was found that VIM and ACTR2 could significantly promote the proliferation of RV in intestinal cells. Through further viral binding assays after knockdown, antibody blocking, and recombinant protein overexpression, it was revealed that both VIM and ACTR2 could promote RV replication.


Assuntos
Proteína 2 Relacionada a Actina , Proteínas do Capsídeo , Mapas de Interação de Proteínas , Rotavirus , Vimentina , Animais , Humanos , Proteína 2 Relacionada a Actina/genética , Proteína 2 Relacionada a Actina/metabolismo , Proteínas do Capsídeo/metabolismo , Intestinos/citologia , Rotavirus/química , Rotavirus/metabolismo , Vimentina/genética , Vimentina/metabolismo , Internalização do Vírus , Replicação Viral , Ligação Proteica
3.
BMC Psychiatry ; 24(1): 144, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378492

RESUMO

BACKGROUND: Insomnia is a common health problem among cancer patients, which is not only a physical problem but also a psychological problem. Sleep plays an important role in the mental and somatic rehabilitation of cancer patients, and the sleep beliefs and attitudes of cancer patients are key factors in improving their sleep situation and quality of life. The aim of this study was to translate the Cancer-Related Dysfunctional Beliefs and Attitudes about Sleep (C-DBAS-14) scale into Chinese and to validate its reliability and validity in cancer patients. METHOD: The C-DBAS-14 scale was translated into Chinese using the backward and forward translation procedure. The reliability of the scale was measured by internal consistency, split-half reliability and retest reliability. The validity of the scale was assessed through the content validity indicators, exploratory factor analysis and validation factor analysis. RESULT: The Cronbach's ɑ coefficient of the Chinese version of the C-DBAS-14 was 0.932 while the McDonald's omega coefficient (ω t) was 0.934. The split-half reliability coefficient was 0.908, and the test-retest reliability was 0.857. The four-factor model was obtained using exploratory factor analysis, explaining 72.7% of the variance, with each item loading greater than 0.4 on the common factor. The results of the confirmatory factor analysis revealed that all indicators of model fit were within an acceptable range, indicating a well-fitting model. CONCLUSION: The Chinese version of the C-DBAS-14 has good reliability and validity among cancer patients. It can be used to measure the sleep beliefs and attitudes of Chinese cancer patients.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Sono , Neoplasias/complicações , Psicometria/métodos , China
4.
Pestic Biochem Physiol ; 202: 105890, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879289

RESUMO

Cytochrome P450 plays a crucial role in regulating insect growth, development, and resisting a variety of stresses. Insect metamorphosis and response to external stress are altered by deleting CYP450 genes. In this study, we identified and analyzed a novel gene of CYP450 family, AccCYP6A13, from Apis cerana cerana, and explored its role in the response of Apis cerana cerana to adverse external stressors. It was found that the expression of AccCYP6A13 was spatiotemporal specificity. The expression level increased with age and reached its highest value in the adult stage. The primarily expressiong location were legs, brain, and epidermis of honeybees. Stress conditions can affect the expression of AccCYP6A13 depending on treatment times. RNA interference experiments have shown that knocking down AccCYP6A13 reduces antioxidant activity and deactivates detoxification enzymes, resulting in oxidative damage accumulation and a decline in detoxification capability in bees, as well as inhibiting numerous antioxidant genes. Additionally, knockdown of the AccCYP6A13 gene in Apis cerana cerana resulted in increased sensitivity to pesticides and increased mortality when treated with neonicotinoid pesticides such as thiamethoxam. AccCYP6A13 overexpression in a prokaryotic system further confirmed its role in resistance to oxidative stress. To summarize, AccCYP6A13 may play an essential role in the normal development and response to environmental stress in Apis cerana cerana. Furthermore, this study contributed to the theoretical understanding of bee resistance biology.


Assuntos
Sistema Enzimático do Citocromo P-450 , Proteínas de Insetos , Estresse Fisiológico , Animais , Abelhas/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Estresse Fisiológico/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Inseticidas/toxicidade , Tiametoxam , Interferência de RNA , Neonicotinoides/toxicidade , Estresse Oxidativo
5.
J Women Aging ; 36(2): 93-106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37556738

RESUMO

OBJECTIVES: This cross-sectional study aims to consider the potential classification of depression and anxiety symptoms among older women, and identify the influencing factors of this classification. METHODS: This study examines Chinese women aged 65 years and older. Latent class analysis was used to explore the mental health subgroups of older women, and multivariate logistic regression was employed to examine the influencing factors based on the health ecological model among these subgroups. RESULTS: The results helped classify this population under three subgroups: the coexistence of depression and anxiety group, dominated depression group, and the low symptoms group. Moreover, class differences in terms of age, residence, education, income, assessment of current life and health status, sleep duration, and health behaviors, such as alcohol use and exercise were noted. CONCLUSIONS: These findings explain the heterogeneity among older women, and help illuminate their unique aspects of mental health. Accordingly, they are significant for scholars and policymakers to understand depression and anxiety among older women.


Assuntos
Ansiedade , Depressão , Humanos , Feminino , Idoso , Depressão/epidemiologia , Análise de Classes Latentes , Estudos Transversais , Ansiedade/epidemiologia , Ansiedade/psicologia , Saúde Mental
6.
Opt Express ; 31(10): 16213-16226, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157705

RESUMO

On the basis of computational ghost imaging (CGI), we present a new imaging technique, feature ghost imaging (FGI), which can convert the color information into distinguishable edge features in retrieved grayscale images. With the edge features extracted by different order operators, FGI can obtain the shape and the color information of objects simultaneously in a single-round detection using one single-pixel detector. The feature distinction of rainbow colors is presented in numerical simulations and the verification of FGI's practical performance is conducted in experiments. Furnishing a new perspective to the imaging of colored objects, our FGI extends the function and the application fields of traditional CGI while sustaining the simplicity of the experimental setup.

7.
Int J Mol Sci ; 25(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38203523

RESUMO

SARS-CoV-2 triggered the global COVID-19 pandemic, posing a severe threat to public health worldwide. The innate immune response in cells infected by SARS-CoV-2 is primarily orchestrated by type I interferon (IFN), with IFN-ß exhibiting a notable inhibitory impact on SARS-CoV-2 replication. FHL2, acting as a docking site, facilitates the assembly of multiprotein complexes and regulates the transcription of diverse genes. However, the association between SARS-CoV-2 and FHL2 remains unclear. In this study, we report for the first time that SARS-CoV-2 infection in Caco2 cells results in the upregulation of FHL2 expression, while the virus's N proteins can enhance FHL2 expression. Notably, the knockdown of FHL2 significantly amplifies SARS-CoV-2 replication in vitro. Conversely, the overexpression of FHL2 leads to a marked reduction in SARS-CoV-2 replication, with the antiviral property of FHL2 being independent of the cell or virus type. Subsequent experiments reveal that FHL2 supports IFN-ß transcription by upregulating the expression and phosphorylation of IRF-3, thereby impeding SARS-CoV-2 replication in cells. These findings highlight FHL2 as a potential antiviral target for treating SARS-CoV-2 infections.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Antivirais/farmacologia , Células CACO-2 , Proteínas com Homeodomínio LIM/genética , Proteínas Musculares/genética , Pandemias , Fatores de Transcrição , Interferon beta/metabolismo
8.
Geriatr Nurs ; 53: 212-217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37556920

RESUMO

AIMS: The mechanisms underlying how stressors affect family adaptation are unclear. This study determined the relationship between stressors and family adaptation among stroke patients, particularly the parallel mediating role of family function and family resilience. METHODS AND RESULTS: The study was conducted in the neurology ward of a tertiary hospital in China. A total of 335 stroke inpatients were interviewed face-to-face from August 2020 to March 2021. A questionnaire was administered that included demographic characteristics, the Family Inventory of Life Events and Changes, Family Apgar Index Scale, Family Hardiness Index Scale, and Family Adaptation Scale. The demographic data and correlations among the research variables were analyzed. A bootstrap method using the SPSS PROCESS macro was employed to test a mediation model. Family adaptation was negatively related to stressors (r = -0.291, p < 0.01) and positively related to family function (r = 0.531, p < 0.01) and family resilience (r = 0.393, p < 0.01). Furthermore, family function and family resilience played parallel mediating roles between stressors and family adaptation. CONCLUSIONS: This study elaborated how stressors interacted with family adaptation through the mediation of family function and family resilience. The findings suggest that enhancement of family function and family resilience may help to improve family adaptation among stroke patients.


Assuntos
Resiliência Psicológica , Humanos , Saúde da Família , Estudos Transversais , Inquéritos e Questionários , China
9.
Opt Express ; 30(20): 35923-35936, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258532

RESUMO

Single-pixel imaging (SPI) can perceive the world using only a single-pixel detector, but long sampling times with a series of patterns are inevitable for SPI, which is the bottleneck for its practical application. Developing new patterns to reduce the sampling times might provide opportunities to address this challenge. Based on the Kronecker product of Hadamard matrix, we here design a complete set of new patterns, called Gao-Boole patterns, for SPI. Compared to orthogonal Hadamard basis patterns with elements valued as +1 or -1, our Gao-Boole patterns are non-orthogonal ones and the element values are designed as +1 or 0. Using our Gao-Boole patterns, the reconstructed quality of a target image (N × N pixels) is as high as the Hadamard one but only with half pattern numbers of the Hadamard ones, for both full sampling (N2 for Gao-Boole patterns, 2N2 for Hadamard basis patterns) and undersampling cases in experiment. Effectively reducing the patterns numbers and sampling times without sacrificing imaging quality, our designed Gao-Boole patterns provide a superior option for structural patterns in SPI and help to steer SPI toward practical imaging application.

10.
Mol Pharm ; 19(5): 1647-1655, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35349292

RESUMO

One of the most significant barriers to the clinical transformation of nanomedicines is low drug distribution in solid tumors due to quick clearance of nanomedicine after injection. Studies have revealed that the distribution of nanomedicine in tumor sites can be considerably improved when the number of nanoparticles supplied in a short period surpasses the threshold. Most routinely employed nanomaterials have dose-related safety concerns. To resolve this problem, we use highly biocompatible albumin to construct blank nanoparticles and doxorubicin loading nanoparticles. Under the guidance of the threshold theory, when the quantity of drug loading nanoparticles is constant, the drug delivery effectiveness improves with the addition of blank nanoparticles. This enhanced impact was verified both in vitro and in vivo. The area under the curve of the high dose group (19.5 × 1011) is 2.5 times higher than that of the low dose group (6.5 × 1011). In addition, the drug distribution of the high dose group at the tumor site was also improved by 1.5 times compared with the low dose group. The results of histopathological sections also showed that the administration of excess blank nanoparticles within 24 h has no damage to the animals. This study contributes to the clinical transition of nanomedicine by providing fresh ideas for anticancer nanomedicine research.


Assuntos
Nanopartículas , Neoplasias , Animais , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Nanomedicina , Neoplasias/tratamento farmacológico , Neoplasias/patologia
11.
J Adv Nurs ; 78(4): 1012-1019, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34449912

RESUMO

AIMS: To explore whether the clinical learning environment (CLE) has an indirect effect on professional identity through the mediation of career self-efficacy (CSE) in nursing students. BACKGROUND: The shortage of nurses has become a universal problem worldwide. Improving nurses' professional identity is considered an effective way to reduce the turnover rate of nurses. However, little is known about the relationship between the CLE, CSE and professional identity. DESIGN: An observational, questionnaire-based, cross-sectional study. METHODS: A web-based survey was completed by 212 undergraduate nursing students from June to August 2018. Measures included Chinese translations of the CLE, the Career Self-Efficacy Scale, and the Professional Identity Scale. RESULTS: Both the CLE (r = 0.552, p < 0.01) and CSE (r = 0.868, p < 0.01) correlated positively with professional identity. The indirect effect of the CLE on professional identity through CSE was positive (ß = 0.342, p < 0.05) and the effect was 77.2%. CONCLUSIONS: A better CLE and higher scores in CSE were associated with professional identity in nursing students, and a better CLE had an indirect effect on the professional identity of students through CSE.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Estudos Transversais , Humanos , Aprendizagem , Autoeficácia , Inquéritos e Questionários
12.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430190

RESUMO

The pandemic of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has posed great threat to the world in many aspects. There is an urgent requirement for an effective preventive vaccine. The receptor binding domain (RBD), located on the spike (S) gene, is responsible for binding to the angiotensin-converting enzyme 2 (ACE2) receptor of host cells. The RBD protein is an effective and safe antigen candidate. The six-helix bundle (6HB) "molecular clamp" is a novel thermally-stable trimerization domain derived from a human immunodeficiency virus (HIV) gp41 protein segment. We selected the baculovirus system to fuse and express the RBD protein and 6HB for imitating the natural trimeric structure of RBD, named RBD-6HB. Recombinant RBD-6HB was successfully obtained from the cell culture supernatant and purified to high homogeneity. The purity of the final protein preparation was more than 97%. The results showed that the protein was identified as a homogeneous polymer. Further studies showed that the RBD-6HB protein combined with AL/CpG adjuvant could stimulate animals to produce sustained high-level antibodies and establish an effective protective barrier to protect mice from challenges. Our findings highlight the importance of trimerized SARS-CoV-2 S protein RBD in designing SARS-CoV-2 vaccines and provide a rationale for developing a protective vaccine through the induction of antibodies against the RBD domain.


Assuntos
COVID-19 , Vacinas Virais , Humanos , Camundongos , Animais , Vacinas contra COVID-19 , Camundongos Endogâmicos BALB C , SARS-CoV-2 , COVID-19/prevenção & controle , Anticorpos
13.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077060

RESUMO

Type III and type I interferon have similar mechanisms of action, and their different receptors lead to different distributions in tissue. On mucosal surfaces, type III interferon exhibits strong antiviral activity. Porcine epidemic diarrhea virus (PEDV) is an economically important enteropathogenic coronavirus, which can cause a high incidence rate and mortality in piglets. Here, we demonstrate that porcine interferon lambda 1 (pIFNL1) and porcine interferon lambda 3 (pIFNL3) can inhibit the proliferation of vesicular stomatitis virus with an enhanced green fluorescent protein (VSV-EGFP) in different cells, and also show strong antiviral activity when PEDV infects Vero cells. Both forms of pIFNLs were shown to be better than porcine interferon alpha (pIFNα), the antiviral activity of pIFNL1 is lower than that of pIFNL3. Therefore, our results provide experimental evidence for the inhibition of PEDV infection by pIFNLs, which may provide a promising treatment for the prevention and treatment of Porcine epidemic diarrhea (PED) in piglets.


Assuntos
Interferon Tipo I , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Chlorocebus aethiops , Interferon Tipo I/metabolismo , Vírus da Diarreia Epidêmica Suína/fisiologia , Suínos , Células Vero
14.
Public Health Nurs ; 39(6): 1204-1212, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35714655

RESUMO

OBJECTIVE: The purpose was to explore the alertness of premonitory symptoms in stroke patients with prehospital delay, and to analyze the influencing factors. DESIGN AND SAMPLE: A cross-sectional study using the convenience sampling method was conducted in the neurology department of a general hospital between November 2018 and July 2019. A total of 352 stroke patients were participated in the survey. MEASURES: A hierarchical multiple regression was performed to analyze the factors related to the alertness of premonitory symptoms (0-9 scores) in stroke patients with prehospital delay. RESULTS: The alertness score was 6.53 ± 2.377. The lowest score of 0.55 ± 0.498 was for "Continuous yawning occurs continuously despite no tiredness or lack of sleep is okay, and need not be treated." The hierarchical regression results revealed that symptom onset, symptom change before admission, knowledge, social support were the influencing factors delaying the alertness of premonitory symptoms. Knowledge and support from friends could improve the alertness, while support from family and other support had a notable negative impact. CONCLUSIONS: Stroke patients need to be more alert toward premonitory symptoms. This alertness is related to stroke knowledge and social support. Nurses should formulate interventions and advise stroke patients to improve their stroke knowledge and expand their social network.


Assuntos
Acidente Vascular Cerebral , Bocejo , Humanos , Estudos Transversais , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Fadiga , Hospitais
15.
Small ; 17(43): e2102408, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34337868

RESUMO

The catalysts for low-temperature selective catalytic reduction of NO with NH3 (NH3 -SCR) are highly desired due to the large demand in industrial furnaces. The characteristic of low-temperature requires the catalyst with rich active sites especially the redox sites. Herein, the authors obtain oxygen defect-rich ß-MnO2 from a crystal phase transformation process during air calcination, by which the as-prepared γ-MnO2 nanosheet and nanorod can be conformally transformed into the corresponding ß-MnO2 . Simultaneously, this transformation accompanies oxygen defects modulation resulted from lattice rearrangement. The most active ß-MnO2 nanosheet with plentiful oxygen defects shows a high efficiency of > 90% NO conversion in an extremely wide operation window of ≈120-350 °C. The detailed characterizations and density functional theory (DFT) calculations reveal that the introduction of oxygen defects enhances the adsorption properties for reactants and decreases the energy barriers of *NH2 formation more than 0.3 eV (≈0.32-0.37 eV), which contributes to a high efficiency of low-temperature SCR activity. The authors finding provides a feasible approach to achieve the oxygen defect engineering and gains insight into manganese-based catalysts for low-temperature NO removal or pre-oxidation.


Assuntos
Compostos de Manganês , Oxigênio , Amônia , Catálise , Oxirredução , Óxidos
16.
Int J Mol Sci ; 21(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948124

RESUMO

Pterostilbene (PTER), a natural dimethylated analog of resveratrol, has been demonstrated to produce anti-neoplastic or neuroprotective actions. However, how and whether this compound can entail any perturbations on ionic currents in electrically excitable cells remains unknown. In whole-cell current recordings, addition of PTER decreased the amplitude of macroscopic Ih during long-lasting hyperpolarization in GH3 cells in a concentration-dependent manner, with an effective IC50 value of 0.84 µM. Its presence also shifted the activation curve of Ih along the voltage axis to a more hyperpolarized potential, by 11 mV. PTER at a concentration greater than 10 µM could also suppress l-type Ca2+ and transient outward K+ currents in GH3 cells. With the addition of PTER, IK(Ca) amplitude was increased, with an EC50 value of 2.23 µM. This increase in IK(Ca) amplitude was attenuated by further addition of verruculogen, but not by tolbutamide or TRAM-39. Neither atropine nor nicotine, in the continued presence of PTER, modified the PTER-stimulated IK(Ca). PTER (10 µM) slightly suppressed the amplitude of l-type Ca2+ current and transient outward K+ current. The presence of PTER (3 µM) was also effective at increasing the open-state probability of large-conductance Ca2+-activated K+ (BKCa) channels identified in hippocampal mHippoE-14 neurons; however, its inability to alter single-channel conductance was detected. Our study highlights evidence to show that PTER has the propensity to perturb ionic currents (e.g., Ih and IK(Ca)), thereby influencing the functional activities of neurons, and neuroendocrine or endocrine cells.


Assuntos
Potenciais da Membrana/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Polaridade Celular/efeitos dos fármacos , Polaridade Celular/fisiologia , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiologia , Transporte de Íons/efeitos dos fármacos , Transporte de Íons/fisiologia , Potenciais da Membrana/fisiologia , Camundongos , Neurônios/química , Neurônios/metabolismo , Neurônios/fisiologia , Técnicas de Patch-Clamp , Hipófise/efeitos dos fármacos , Hipófise/fisiologia , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/fisiologia , Ratos
17.
Int J Mol Sci ; 21(2)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936301

RESUMO

Oxaliplatin (OXAL) is regarded as a platinum-based anti-neoplastic agent. However, its perturbations on membrane ionic currents in neurons and neuroendocrine or endocrine cells are largely unclear, though peripheral neuropathy has been noted during its long-term administration. In this study, we investigated how the presence of OXAL and other related compounds can interact with two types of inward currents; namely, hyperpolarization-activated cation current (Ih) and membrane electroporation-induced current (IMEP). OXAL increased the amplitude or activation rate constant of Ih in a concentration-dependent manner with effective EC50 or KD values of 3.2 or 6.4 µM, respectively, in pituitary GH3 cells. The stimulation by this agent of Ih could be attenuated by subsequent addition of ivabradine, protopine, or dexmedetomidine. Cell exposure to OXAL (3 µM) resulted in an approximately 11 mV rightward shift in Ih activation along the voltage axis with minimal changes in the gating charge of the curve. The exposure to OXAL also effected an elevation in area of the voltage-dependent hysteresis elicited by long-lasting triangular ramp. Additionally, its application resulted in an increase in the amplitude of IMEP elicited by large hyperpolarization in GH3 cells with an EC50 value of 1.3 µM. However, in the continued presence of OXAL, further addition of ivabradine, protopine, or dexmedetomidine always resulted in failure to attenuate the OXAL-induced increase of IMEP amplitude effectively. Averaged current-voltage relation of membrane electroporation-induced current (IMEP) was altered in the presence of OXAL. In pituitary R1220 cells, OXAL-stimulated Ih remained effective. In Rolf B1.T olfactory sensory neurons, this agent was also observed to increase IMEP in a concentration-dependent manner. In light of the findings from this study, OXAL-mediated increases of Ih and IMEP may coincide and then synergistically act to increase the amplitude of inward currents, raising the membrane excitability of electrically excitable cells, if similar in vivo findings occur.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Células Neuroendócrinas/efeitos dos fármacos , Oxaliplatina/efeitos adversos , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Cátions/farmacologia , Eletroporação , Humanos , Camundongos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Oxaliplatina/farmacologia , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/patologia
18.
Int J Mol Sci ; 21(7)2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-32235313

RESUMO

Mature mammalian hearts possess very limited regenerative potential. The irreversible cardiomyocyte loss after heart injury can lead to heart failure and death. Pluripotent stem cells (PSCs) can differentiate into cardiomyocytes for cardiac repair, but there are obstacles to their clinical application. Among these obstacles is their potential for post-transplant rejection. Although human amniotic fluid-derived stem cells (hAFSCs) are immune privileged, they cannot induce cardiac differentiation. Thus, we generated hAFSC-derived induced PSCs (hAFSC-iPSCs) and used a Wnt-modulating differentiation protocol for the cardiac differentiation of hAFSC-iPSCs. In vitro studies using flow cytometry, immunofluorescence staining, and patch-clamp electrophysiological study, were performed to identify the characteristics of hAFSC-iPSC-derived cardiomyocytes (hAFSC-iPSC-CMs). We injected hAFSC-iPSC-CMs intramuscularly into rat infarcted hearts to evaluate the therapeutic potential of hAFSC-iPSC-CM transplantation. At day 21 of differentiation, the hAFSC-iPSC-CMs expressed cardiac-specific marker (cardiac troponin T), presented cardiomyocyte-specific electrophysiological properties, and contracted spontaneously. Importantly, these hAFSC-iPSC-CMs demonstrated low major histocompatibility complex (MHC) class I antigen expression and the absence of MHC class II antigens, indicating their low immunogenicity. The intramyocardial transplantation of hAFSC-iPSC-CMs restored cardiac function, partially remuscularized the injured region, and reduced fibrosis in the rat infarcted hearts. Therefore, hAFSC-iPSCs are potential candidates for the repair of infarcted myocardium.


Assuntos
Líquido Amniótico/citologia , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Privilégio Imunológico , Células-Tronco Pluripotentes Induzidas/citologia , Desenvolvimento Muscular , Miócitos Cardíacos/citologia , Animais , Biomarcadores , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos , Humanos , Imuno-Histoquímica , Células-Tronco Pluripotentes Induzidas/imunologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Fenótipo , Ratos , Regeneração , Transplante de Células-Tronco/métodos , Resultado do Tratamento , Função Ventricular Esquerda
19.
Int J Mol Sci ; 20(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795416

RESUMO

Roxadustat (FG-4592), an analog of 2-oxoglutarate, is an orally-administered, heterocyclic small molecule known to be an inhibitor of hypoxia inducible factor (HIF) prolyl hydroxylase. However, none of the studies have thus far thoroughly investigated its possible perturbations on membrane ion currents in endocrine or heart cells. In our studies, the whole-cell current recordings of the patch-clamp technique showed that the presence of roxadustat effectively and differentially suppressed the peak and late components of IK(DR) amplitude in response to membrane depolarization in pituitary tumor (GH3) cells with an IC50 value of 5.71 and 1.32 µM, respectively. The current inactivation of IK(DR) elicited by 10-sec membrane depolarization became raised in the presence of roxadustatt. When cells were exposed to either CoCl2 or deferoxamine (DFO), the IK(DR) elicited by membrane depolarization was not modified; however, nonactin, a K+-selective ionophore, in continued presence of roxadustat, attenuated roxadustat-mediated inhibition of the amplitude. The steady-state inactivation of IK(DR) could be constructed in the presence of roxadustat. Recovery of IK(DR) block by roxadustat (3 and 10 µM) could be fitted by a single exponential with 382 and 523 msec, respectively. The roxadustat addition slightly suppressed erg-mediated K+ or hyperpolarization-activated cation currents. This drug also decreased the peak amplitude of voltage-gated Na+ current with a slowing in inactivation rate of the current. Likewise, in H9c2 heart-derived cells, the addition of roxadustat suppressed IK(DR) amplitude in combination with the shortening in inactivation time course of the current. In high glucose-treated H9c2 cells, roxadustat-mediated inhibition of IK(DR) remained unchanged. Collectively, despite its suppression of HIF prolyl hydroxylase, inhibitory actions of roxadustat on different types of ionic currents possibly in a non-genomic fashion might provide another yet unidentified mechanism through which cellular functions are seriously perturbed, if similar findings occur in vivo.


Assuntos
Glicina/análogos & derivados , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Transporte de Íons/efeitos dos fármacos , Isoquinolinas/farmacologia , Inibidores de Prolil-Hidrolase/farmacologia , Animais , Linhagem Celular Tumoral , Glicina/farmacologia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Potássio/metabolismo , Ratos , Sódio/metabolismo
20.
Molecules ; 24(23)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766737

RESUMO

The triterpenoid fraction of Ganoderma (Ganoderma triterpenoids, GTs) has been increasingly demonstrated to provide effective antioxidant, neuroprotective or cardioprotective activities. However, whether GTs is capable of perturbing the transmembrane ionic currents existing in electrically excitable cells is not thoroughly investigated. In this study, an attempt was made to study whether GTs could modify hyperpolarization-activated cation currents (Ih) in pituitary tumor (GH3) cells and in HL-1 atrial cardiomyocytes. In whole-cell current recordings, the addition of GTs produced a dose-dependent reduction in the amplitude of Ih in GH3 cells with an IC50 value of 11.7 µg/mL, in combination with a lengthening in activation time constant of the current. GTs (10 µg/mL) also caused a conceivable shift in the steady-state activation curve of Ih along the voltage axis to a more negative potential by approximately 11 mV. Subsequent addition of neither 8-cyclopentyl-1,3-dipropylxanthine nor 8-(p-sulfophenyl)theophylline, still in the presence of GTs, could attenuate GTs-mediated inhibition of Ih. In current-clamp voltage recordings, GTs diminished the firing frequency of spontaneous action potentials in GH3 cells, and it also decreased the amplitude of sag potential in response to hyperpolarizing current stimuli. In murine HL-1 cardiomyocytes, the GTs addition also suppressed the amplitude of Ih effectively. In DPCPX (1 µM)-treated HL-1 cells, the inhibitory effect of GTs on Ih remained efficacious. Collectively, the inhibition of Ih caused by GTs is independent of its possible binding to adenosine receptors and it might have profound influence in electrical behaviors of different types of electrically excitable cells (e.g., pituitary and heart cells) if similar in vitro or in vivo findings occur.


Assuntos
Ganoderma/química , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/efeitos dos fármacos , Miócitos Cardíacos/citologia , Neoplasias Hipofisárias/metabolismo , Triterpenos/farmacologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Técnicas de Patch-Clamp , Esporos Fúngicos/química
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