RESUMEN
Plastic-crystal-embedded elastomer electrolytes (PCEEs), produced through polymerization-induced phase separation (PIPS), are gaining popularity as solid polymer electrolytes (SPEs). However, it remains to be investigated whether all monomer molecules can achieve polymerization-induced phase separation and the corresponding differences in lithium metal battery performance. Herein, we prepared PCEEs with different functional groups (OH, CN, F) through in situ polymerization. Research findings show that PCEE containing - CN or - F achieves the separation of the plastic crystalline phase and succinonitrile (SN) phase, whereas PCEE containing OH cannot due to hydrogen bonding with the SN phase. Notably, the PCEE synthesized with the F monomer (FBA-PCEE) exhibited exceptional interfacial stability with lithium metal anodes and lithium iron phosphate (LFP) cathodes, due to its unique coordination mechanism with lithium ions. The FBA-PCEE demonstrated a high ionic conductivity (2.02 × 10-3 S cm-1) and lithium-ion migration number ( [Formula: see text] = 0.75). Moreover, lithium symmetric cells incorporating FBA-PCEE demonstrated stable cycling performance for more than 1000 h at a current density of 0.1 mA cm-2, resulting in the development of a solid electrolyte interphase (SEI) rich in LiF, Li3N, and Li2CO3 over time. Additionally, incorporating FBA-PCEE facilitated the stable cycling of LPF over 1000 cycles at 0.5C, maintaining a capacity retention of 77.38 % after 500 cycles. When coupled with high-voltage Nickel Cobalt Manganese Oxide (NCM-622) cathodes and lithium metal anodes, a discharge capacity of 119.70 mAh g-1 at 0.1C was sustained after 100 cycles, exhibiting a capacity retention of 78.95 %. This study elucidates the critical role of monomer design in achieving PIPS, offering valuable insights into developing high-performance polymer composite electrolytes for advanced lithium metal batteries.
RESUMEN
AIMS: Sepsis pathophysiology is complex and identifying effective treatments for sepsis remains challenging. The study aims to identify effective drugs and targets for sepsis through transcriptomic analysis of sepsis patients, repositioning analysis of compounds, and validation by animal models. MAIN METHODS: GSE185263 obtained from the GEO database that includes gene expression profiles of 44 healthy controls and 348 sepsis patients categorized by severity. Bioinformatic algorithms revealed the molecular, function, and immune characteristics of the sepsis, and constructed sepsis-related protein-protein interaction networks. Subsequently, Random Walk with Restart analysis was applied to identify candidate drugs for sepsis, which were tested in animal models for survival, inflammation, coagulation, and multi-organ damage. KEY FINDINGS: Our analysis found 1862 genes linked to sepsis development, enriched in functions like neutrophil extracellular trap formation (NETs) and complement/coagulation cascades. With disease progression, immune activation-associated cells were inhibited, while immune suppression-associated cells were activated. Next, the drug repositioning method identified candidate drugs, such as alpha-1 antitrypsin, that may play a therapeutic role by targeting neutrophil elastase (NE) to inhibit NETs. Animal experiments proved that alpha-1 antitrypsin treatment can improve the survival rate, reduce sepsis score, reduce the levels of inflammation markers in serum, and alleviate muti-organ morphological damage in mice with sepsis. The further results showed that α-1 antitrypsin can inhibit the NETs by suppressing the NE for the treatment of sepsis. SIGNIFICANCE: Alpha-1 antitrypsin acted on the NE to inhibit NETs thereby protecting mice from sepsis-induced inflammation and coagulation.
Asunto(s)
Coagulación Sanguínea , Trampas Extracelulares , Inflamación , Elastasa de Leucocito , Sepsis , alfa 1-Antitripsina , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Sepsis/metabolismo , Animales , Elastasa de Leucocito/metabolismo , Trampas Extracelulares/efectos de los fármacos , Trampas Extracelulares/metabolismo , Ratones , alfa 1-Antitripsina/farmacología , alfa 1-Antitripsina/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Coagulación Sanguínea/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos C57BL , Neutrófilos/metabolismo , Neutrófilos/efectos de los fármacos , Modelos Animales de EnfermedadRESUMEN
Ammonium vanadate with stable bi-layered structure and superior mass-specific capacity have emerged as competitive cathode materials for aqueous rechargeable zinc-ion batteries (AZIBs). Nevertheless, fragile NH O bonds and too strong electrostatic interaction by virtue of excessive NH4+ will lead to sluggish Zn2+ ion mobility, further largely affects the electro-chemical performance of ammonium vanadate in AZIBs. The present work incorporates polypyrrole (PPy) to partially replace NH4+ in NH4V4O10 (NVO), resulting in the significantly enlarged interlayers (from 10.1 to 11.9 Å), remarkable electronic conductivity, increased oxygen vacancies and reinforced layered structure. The partial removal of NH4+ will alleviate the irreversible deammoniation to protect the laminate structures from collapse during ion insertion/extraction. The expanded interlayer spacing and the increased oxygen vacancies by the virtue of the introduction of polypyrrole improve the ionic diffusion, enabling exceptional rate performance of NH4V4O10. As expected, the resulting polypyrrole intercalated ammonium vanadate (NVOY) presents a superior discharge capacity of 431.9 mAh g-1 at 0.5 A g-1 and remarkable cycling stability of 219.1 mAh g-1 at 20 A g-1 with 78 % capacity retention after 1500 cycles. The in-situ electrochemical impedance spectroscopy (EIS), in-situ X-ray diffraction (XRD), ex-situ X-ray photoelectron spectroscopy (XPS) and ex-situ high resolution transmission electron microscopy (HR-TEM) analysis investigate a highly reversible intercalation Zn-storage mechanism, and the enhanced the redox kinetics are related to the combined effect of interlayer regulation, high electronic conductivity and oxygen defect engineering by partial substitution NH4+ of PPy incorporation.
RESUMEN
Autophagy is closely related to the aging of various organ systems, including ovaries. Quercetin has a variety of biological activities, including potential regulation of autophagy. However, whether quercetin-regulated autophagy activity affects the process of ovarian aging and injury has not been clarified yet. This study explores whether quercetin can resist H2O2-induced aging and injury of granulosa cells by regulating autophagy and its related molecular mechanisms in vitro experiments. The cell viability, endocrine function, cell aging, and apoptosis were detected to evaluate the effects of quercetin and autophagy regulators like 3-methyladenine and rapamycin. The levels of autophagy markers Atg5, Atg12, Atg16L, Lc3B II/I, and Beclin1 were determined by Western blot to assess the effects of quercetin, 3-methyladenine and rapamycin on autophagy. Our results showed quercetin resisted H2O2-induced granulosa cell aging and injury by activating protective autophagy. The treatment of 3-methyladenine and rapamycin confirmed the protective function of autophagy in H2O2-induced granulosa cells. 3-methyladenine treatment inhibited the expression of autophagy markers Atg5, Atg12, Atg16L, Lc3B II/I, and Beclin1 and abolished the positive effects on cell viability, estradiol secretion, and cell apoptosis activated by quercetin. In conclusion, quercetin activates autophagy by upregulating the expression of autophagy-related proteins to resist H2O2-induced aging and injury, which is crucial for stabilizing the function of granulosa cells under oxidative injury conditions and delaying aging. This study may explain the protective effects of quercetin on ovarian aging and injury from the perspective of regulating autophagy.
Asunto(s)
Peróxido de Hidrógeno , Quercetina , Femenino , Ratas , Animales , Quercetina/farmacología , Peróxido de Hidrógeno/toxicidad , Peróxido de Hidrógeno/metabolismo , Beclina-1/metabolismo , Células de la Granulosa , Envejecimiento , Apoptosis , Autofagia , Sirolimus/farmacologíaRESUMEN
Impacts of Mn alloying on lattice stabilities, magnetic properties, electronic structures of the bcc and fcc phases and the fccâbcc phase transition in Fe16-xMnx (x = 0, 1 and 2) alloys are studied by first-principles calculations. Results show that the doped Mn atom prefers ferromagnetic and antiferromagnetic interaction with the host Fe atoms in the bcc and fcc phases, respectively. In these two phases, the magnetic moment of Mn is smaller and larger than Fe, respectively. The local moment of Fe is decided by the Fe-Mn distance in the bcc phase, whereas in the fcc phase, it is determined by spatial orientation with Mn. In the different phases, Mn prefers different site occupations, which can be understood from the electronic density of states near Fermi energy, implying a possibility of element redistribution during phase transition. The driving force of phase transition decreases with Mn alloying. Both destabilized bcc phase and stabilized fcc phase contribute to the inhibited phase transition, but the latter plays a dominant role. Antiferromagnetism is recognized as the key reason for the enhanced stability of the fcc phase by Mn alloying.
RESUMEN
Achieving practical applications of PEO-based composite solid electrolyte (CPE) batteries requires the precise design of filler structures at the molecular level to form stable composite interfacial phases, which in turn improve the conductivity of Li+ and inhibit the nucleation growth of lithium dendrites. Some functional fillers suffer from severe agglomeration due to poor compatibility with the polymer base or grain boundary migration, resulting in limited improvement in cell performance. In this paper, ILs@KAP1 is reported as a filler to enhance the performance of PEO-based batteries. Thereinto, the hypercrosslinked phosphorus ligand polymer-containing KAP1, designed at the molecular level, has an abundant porous structure, hydrogen bonding network, and a rigid skeleton structure of benzene rings. These can be used both to improve the flammability with PEO-based and to reduce the crystallinity of the polymer electrolyte. Ionic liquids (ILs) are encapsulated in the nanochannels of KAP1, and thus a 3D Li+ conducting framework could be formed. In this case, it could not only facilitate the wettability of the contact interface with the electrode, significantly promoting its compatibility and providing a fast Li+ transport path, but also facilitate the formation of LiF, Li3N and Li2O rich SEI components, further fostering the uniform deposition/exfoliation of lithium. The LFP||CPE||Li battery assembled with ILs@KAP1-PEO-CPE has a high initial discharge specific capacity about 156 mAh/g at 1C and a remaining capacity about 121.8 mAh/g after 300 cycles (capacity retention of 78.07%).
RESUMEN
Resveratrol performs a variety of biological activities, including the potential regulation of autophagy. However, it is unclear whether resveratrol protects against luteal dysfunction and whether autophagy involves the regulation of resveratrol. This study aims to investigate whether resveratrol can regulate autophagy to resist H2O2-induced luteinized granulosa cell dysfunction in vitro. Our results showed that resveratrol can enhance cell viability, stimulate the secretion of progesterone and estradiol, and resist cell apoptosis in H2O2-induced luteinized granulosa cell dysfunction. Resveratrol can activate autophagy by stimulating the expression of autophagy-related genes at the transcriptional and translational levels and increasing the formation of autophagosomes and autophagolysosomes. Rapamycin, 3-methyladenine, and bafilomycin A1 regulated the levels of autophagy-related genes in H2O2-induced luteinized granulosa cell dysfunction and further confirmed the protective role of autophagy activated by resveratrol. In conclusion, resveratrol activates autophagy to resist H2O2-induced oxidative dysfunction, which is crucial for stabilizing the secretory function of luteinized granulosa cells and inhibiting apoptosis. This study may contribute to revealing the protective effects of resveratrol on resisting luteal dysfunction from the perspective of regulating autophagy.
Asunto(s)
Células de la Granulosa , Peróxido de Hidrógeno , Femenino , Ratas , Animales , Resveratrol/farmacología , Resveratrol/metabolismo , Peróxido de Hidrógeno/metabolismo , Células de la Granulosa/metabolismo , Progesterona/metabolismo , Autofagia , Células CultivadasRESUMEN
Free-falling cubic Test Masses (TMs) are a key component of the interferometer used for low-frequency gravitational wave (GW) detection in space. However, exposure to energetic particles in the environment can lead to electrostatic charging of the TM, resulting in additional electrostatic and Lorentz forces that can impact GW detection sensitivity. To evaluate this effect, the high-energy proton data set of the Geostationary Operational Environmental Satellite (GOES) program was used to analyze TM charging due to Solar Proton Events (SPEs) in the 24th solar cycle. Using the Geant4 Monte Carlo toolkit, the TM charging process is simulated in a space environment for SPEs falling into three ranges of proton flux: (1) greater than 10 pfu and less than 100 pfu, (2) greater than 100 pfu and less than 1000 pfu, and (3) greater than 1000 pfu. It is found that SPEs charging can reach the threshold within 535 s to 18.6 h, considering a reasonable discharge threshold of LISA and Taiji. We demonstrate that while there is a somewhat linear correlation between the net charging rate of the TM and the integrated flux of [Formula: see text] 10 MeV SPEs, there are many cases in which the integrated flux is significantly different from the charging rate. Therefore, we investigate the difference between the integral flux and the charging rate of SPEs using the charging efficiency assessment method. Our results indicate that the energy spectrum structure of SPEs is the most important factor influencing the charging rate. Lastly, we evaluate the charging probability of SPEs in the 24th solar cycle and find that the frequency and charging risk of SPEs are highest in the 3rd, 4th, 5th, 6th, and 7th years, which can serve as a reference for future GW detection spacecraft.
RESUMEN
INTRODUCTION: This paper aims to reveal the molecular mechanism of resveratrol against oxidative stress and cell injury. The ovarian granulosa-lutein cell injury and apoptosis induced by oxidative stress may be responsible for female luteal phase deficiency. The antioxidant function of resveratrol has been confirmed; however, its effect on the expression of antioxidant enzymes and regulatory mechanisms in ovarian granulosa-lutein cells remains unclear. OBJECTIVE: This study aimed to investigate the role of the SIRT1/Nrf2/ARE signaling pathway in the effect of resveratrol on the hydrogen peroxide-induced injury of rat ovarian granulosa-lutein cells. METHODS: In this study, ovarian granulosa-lutein cells extracted from 3-week female SD rats were treated with 200 µM H2O2 in the presence or absence of 20 µM resveratrol. siRNA-SIRT1 and siRNA-Nrf2 were used to inhibit the expression of SIRT1 and Nrf2, respectively. Cell counting kit 8 (CCK-8), cellular morphology, progesterone secretion, and estradiol were used to evaluate cell injury. Hoechst 33258 staining was used to measure cell apoptosis. DHE staining, DCFH-DA staining, malondialdehyde content, protein carbonyl content, total antioxidant capacity and SOD viability were used to estimate the levels of oxidative stress. Western blot analysis was used to detect the levels of apoptosis-related proteins, and SIRT1/Nrf2/ARE signaling pathway-related proteins. RESULTS: The H2O2 treatment-induced rat ovarian granulosa-lutein cells injury was shown as decreased cell viability, impaired cellular morphology, and decreased levels of progesterone and estradiol. The H2O2 treatment also exacerbated cell apoptosis demonstrated as more apoptotic cells stained by Hoechst staining, decreased level of anti-apoptosis protein Bcl-2 and increased level of pro-apoptosis protein Bax. These effects of cell injury and apoptosis induced by H2O2 can be ameliorated by resveratrol. Resveratrol also alleviated oxidative stress induced by H2O2, supported by decreased superoxide anion and cellular total ROS, decreased malondialdehyde and protein carbonyl levels, and increased total antioxidant capacity and SOD viability. Western blot results demonstrated resveratrol reversed the H2O2-induced decrease in levels of antioxidant enzymes containing ARE sequences and activated SIRT1/Nrf2 pathway. Further treatment by siRNA-Nrf2 suggested resveratrol could not activate the expression of antioxidant enzymes under a condition of inhibition of Nrf2. CONCLUSION: This study demonstrates that resveratrol attenuated oxidative stress to protect H2O2-induced rat ovarian granulosa-lutein cell injury and apoptosis via SIRT1/Nrf2/ARE signaling pathway.
Asunto(s)
Antioxidantes , Células Lúteas , Ratas , Femenino , Animales , Resveratrol/farmacología , Antioxidantes/farmacología , Antioxidantes/metabolismo , Peróxido de Hidrógeno/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Células Lúteas/metabolismo , Progesterona/metabolismo , Progesterona/farmacología , Sirtuina 1/metabolismo , Carbonilación Proteica , Ratas Sprague-Dawley , Estrés Oxidativo , Transducción de Señal , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/farmacología , ARN Interferente Pequeño/farmacología , Estradiol/farmacología , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/farmacología , Malondialdehído/metabolismo , Malondialdehído/farmacología , Especies Reactivas de Oxígeno/metabolismoRESUMEN
BACKGROUND: The flipped classroom approach has gained increasing popularity in medical education. Physiology is a basic medical course that studies the phenomena and laws of human life activities, and is a crucial link course connecting preclinical courses and clinical courses. However, there is a paucity of data showing the effectiveness of the flipped classroom model for the entirety of physiology course in medical undergraduate students. METHOD: 131 sophomore students with clinical medicine major at Harbin Medical University were recruited and they were randomly allocated into two groups: the control group which was subjected to traditional lecture teaching (n = 69), and the experimental group which was subjected to flipped classroom teaching (n = 62). To assess the effect of flipped teaching, the usual performance and final exam scores were used to evaluate the physiology learning effectiveness of students. The correlation between the usual performance and final exam scores by Pearson method was also conducted in the two teaching groups. After course completion, an anonymous questionnaire survey was conducted among the subjects of flipped classroom group to assess students' opinion regarding the flipped classroom teaching. RESULTS: Our results showed that the usual performance and final exam scores of students in the flipped classroom were both significantly higher than that in the traditional teaching class (P < 0.05). Moreover, our results also showed that the usual performance of students was significantly correlated with the final exam scores in the flipped classroom (r = 0.3945, P < 0.01), but not in the traditional teaching group (r = 0.1522, P = 0.2119). The results of questionnaire survey showed that 77.58% of the students believed flipped classroom teaching improved their knowledge acquisition. 70%~86% of students perceived that flipped classroom enhanced their learning abilities, including self-study ability, collaborative learning and problem-solving skills, and clinical thinking ability. In addition, about 60% of students acknowledged the teaching design and teaching environment, more students' engagement and presentation of group learning in the flipped classroom. CONCLUSION: The flipped classroom teaching significantly improved students' learning effectiveness in physiology course, as indicated by final exam score and usual performance. It also promoted higher-order ability-set acquisition and allowed a rationalized formative evaluation system.
Asunto(s)
Educación Médica , Estudiantes de Medicina , Humanos , Curriculum , Aprendizaje , Aprendizaje Basado en Problemas/métodos , Encuestas y CuestionariosRESUMEN
Three-dimensional (3D) heterotypic multicellular spheroid models play important roles in researches of the proliferation and remodeling phases in wound healing. This study aimed to develop a sessile drop array to cultivate 3D spheroids and simulate wound healing stage in vitro using NIH-3T3 fibroblasts and M2-type macrophages. By the aid of the offset of surface tension and gravity, the sessile drop array is able to transfer cell suspensions to spheroids via the superhydrophobic surface of each microwell. Meanwhile, each microwell has a cylinder hole at its bottom that provides adequate oxygen to the spheroid. It demonstrated that the NIH-3T3 fibroblast spheroid and the 3T3 fibroblast/M2-type macrophage heterotypic multicellular spheroid can form and maintain physiological activities within nine days. In order to further investigate the structure without destroying the entire spheroid, we reconstructed its 3D morphology using transparent processing technology and the Z-stack function of confocal microscopy. Additionally, a nano antibody-based 3D immunostaining assay was used to analyze the proliferation and differentiation characteristics of these cells. It found that M2-type macrophages were capable of promoting the differentiation of 3T3 fibroblast spheroid. In this study, a novel, inexpensive platform was constructed for developing spheroids, as well as a 3D immunofluorescence method for investigating the macrophage-associated wound healing microenvironment.
Asunto(s)
Técnicas Biosensibles , Técnicas de Cocultivo , Macrófagos , Esferoides Celulares , FibroblastosRESUMEN
Primary spontaneous pneumothorax (PSP) or pulmonary cyst is one of the manifestations of Birt-Hogg-Dubé syndrome, which is caused by pathogenic variants in FLCN gene. Genetic testing in patients with PSP identifies a certain number of missense or intronic variants. These variants are usually considered as variants of uncertain significance, whose functional interpretations pose a challenge in clinical genetics. To improve recognition of pathogenic splice-altering variants in FLCN gene, computational tools are used to prioritize potential splice-altering variants and then a hybrid minigene assay is performed to verify the RNA splicing pattern. Herein, variants in FLCN exon 11 and its flanking sequence are focused. Eight variants detected in 11 patients with PSP are evaluated, and six variants are prioritized by in silico tools as potential splice-altering variants of uncertain significance. Four variants (c.1177-5_1177-3delCTC, c.1292_1300+4del, c.1300+4C>T, and c.1300+5G>A) are demonstrated by minigene assay to alter RNA splicing of FLCN, and the last three of them are novel. RT-PCR of patient-derived RNA gives consistent results. Genotype-phenotype correlation analysis in patients with PSP with these variants demonstrates good concordance. Our results underline the importance of RNA analysis, which could provide molecular evidence for pathogenicity of a variant, and provide essential information for the clinical interpretation of variants. Combining the clinical information, a definitive diagnosis could be made.
Asunto(s)
Patología Molecular , Proteínas Supresoras de Tumor , Genes Supresores de Tumor , ARN , Proteínas Supresoras de Tumor/genética , Virulencia , HumanosRESUMEN
Correction for 'First-principles insights into hydrogen trapping in interstitial-vacancy complexes in vanadium carbide' by Shuai Tang et al., Phys. Chem. Chem. Phys., 2022, DOI: https://doi.org/10.1039/d2cp02425j.
RESUMEN
Hydrogen trapping is a key factor in designing advanced vanadium alloys and steels, where the influence of carbon vacancies is still elusive. Herein we have investigated the effect of carbon vacancies on the hydrogen trapping of defect-complexes in vanadium carbide using first-principles calculations. When a carbon vacancy is present, the second nearest neighboring trigonal interstitial is a stable hydrogen trapping site. A C vacancy enhances the hydrogen trapping ability by reducing the chemical and mechanical effects on H atom solution energy. Electronic structure analysis shows that C vacancies increase the charge density and the Bader atomic volume, leading to a lower H atom solution energy. The strength of the V-H bond is predominant in determining the hydrogen trapping ability in the presence of a C vacancy, in contrast to that of a C-H bond when the C vacancy is absent.
RESUMEN
INTRODUCTION: Group A Streptococcus (GAS) can produce streptococcal secreted esterase (Sse), which inhibits neutrophil recruitment to the site of infection and is crucial for GAS pathogenesis. As an effective esterase, Sse hydrolyzes the sn-2 ester bond of human platelet-activating factor, inactivating it and abolishing its ability to recruit neutrophils. OBJECTIVES: The purpose of this study was to investigate the effects of sse deletion on the virulence of multiple serotypes of GAS. METHODS: Isogenic strains that lack the sse gene (Δsse) were derived from the parent strains MGAS5005 (serotype M1, CovRS mutant), MGAS2221 (serotype M1, wild-type CovRS), MGAS315 (serotype M3, CovRS mutant) and MGAS6180 (serotype M28, wild-type CovRS) and were used to study the differences in virulence and pathogenicity of GAS serotypes. RESULTS: In a subcutaneous infection model, mice infected with MGAS5005Δsse exhibited higher survival rates but decreased dissemination to the organs compared with mice infected with MGAS5005. When mice were infected with the four Δsse mutants, the MPO activity and IFN-γ, TNF-α, IL-2 and IL-6 levels increased, but the skin lesion sizes decreased. In an intraperitoneal infection model, the absence of Sse significantly reduced the virulence of GAS, leading to increased mouse survival rates and decreased GAS burdens in the organs in most of the challenge experiments. In addition, the numbers of the four Δsse mutants were greatly reduced 60 min after incubation with isolated rat neutrophils. CONCLUSION: Our results suggest that Sse participates in the pathogenesis of multiple GAS serotypes (MGAS5005, MGAS2221, MGAS315 and MGAS6180), particularly the hypervirulent CovS mutant strains MGAS5005 and MGAS315. These strain differences were positively correlated with the virulence of the serotype.
Asunto(s)
Esterasas , Infecciones Estreptocócicas , Animales , Proteínas Bacterianas , Humanos , Ratones , Ratas , Serogrupo , Streptococcus pyogenes , VirulenciaRESUMEN
BACKGROUND: The increased risk of cardiovascular disease (CVD) in postmenopausal women and ovariectomized patients suggests that estrogen has a protective effect on cardiac function. Oxidative stress is the main cause of CVD, and the cellular defensive Nrf2 antioxidant pathway plays a protective role in various pathologies. However, the regulation of Nrf2 by estrogen has received little attention. OBJECTIVE: The present study aimed to investigate the role of Nrf2 in the effect of estrogen on cardiac function. METHODS: In the present study, female SD rats were divided into three groups as follows: sham operation (SHAM), bilateral ovariectomy (OVX) and bilateral ovariectomy with estradiol valerate (EV) supplementation (OVX+EV). Vaginal smears and E2 concentrations were used to confirm the success of the model. We compared cardiac morphology and function by echocardiography and HE staining. The levels of oxidative stress markers and antioxidant enzymes as well as protein expression of antioxidant genes were evaluated by Western blotting and immunohistochemistry. RESULTS: Our results showed that supplementation with estrogen restored the parameters to some extent. Left ventricular end diastolic diameter at diastolic (LVID;d) and left ventricular volume at diastolic (LV vol;d) increased but MV E wave/A wave (E/A) significantly decreased. The oxidative stress indicators (malondialdehyde) increased, and the antioxidant activity indicators, such as superoxide dismutase (SOD) and catalase (CAT), decreased. Further, the expression of most Nrf2 antioxidant pathway-related proteins in the heart decreased after ovariectomy. CONCLUSION: The present study demonstrated that estrogen may protect cardiac function by regulating antioxidant capacity through the Nrf2 pathway.
Asunto(s)
Factor 2 Relacionado con NF-E2 , Estrés Oxidativo , Animales , Estradiol/farmacología , Femenino , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Ovariectomía , Ratas , Ratas Sprague-Dawley , Transducción de SeñalRESUMEN
Birt-Hogg-Dubé syndrome (BHDS, MIM #135150), caused by germline mutations of FLCN gene, is a rare autosomal dominant inherited disorder characterized by skin fibrofolliculomas, renal cancer, pulmonary cysts and spontaneous pneumothorax. The syndrome is considered to be under-diagnosed due to variable and atypical manifestations. Herein we present a BHDS family. Targeted next generation sequencing (NGS) and multiplex ligation-dependent probe amplification (MLPA) revealed a novel FLCN intragenic deletion spanning exons 10-14 in four members including the proband with pulmonary cysts and spontaneous pneumothorax, one member with suspicious skin lesions and a few pulmonary cysts, as well as two asymptomatic family members. In addition, a linkage analysis further demonstrated one member with pulmonary bullae to be a BHDS-ruled-out case, whose bullae presented more likely as an aspect of paraseptal emphysema. Furthermore, the targeted NGS and MLPA data including our previous and present findings were reviewed and analyzed to compare the advantages and disadvantages of the two methods, and a brief review of the relevant literature is included. Considering the capability of the targeted NGS method to detect large intragenic deletions as well as determining deletion junctions, and the occasional false positives of MLPA, we highly recommend targeted NGS to be used for clinical molecular diagnosis in suspected BHDS patients.
RESUMEN
Streptococcal secreted esterase (Sse) is a platelet-activating factor acetylhydrolase that is critical for Group A Streptococcus (GAS) skin invasion and innate immune evasion. There are two Sse variant complexes that share >98% identity within each complex but display about 37% variation between the complexes in amino acid sequences. Sse immunization protects mice against lethal infection and skin invasion in subcutaneous infection with the hypervirulent CovRS mutant strain, MGAS5005. However, it is not known whether Sse immunization provides significant protection against infection of GAS with functional CovRS and whether immunization with Sse of one variant complex provides protection against infection of GAS that produces Sse of another variant complex. This study was designed to address these questions. Mice were immunized with recombinant Sse of M1 GAS (SseM1) and challenged with MGAS5005 (serotype M1, CovS mutant, and Sse of variant complex I), MGAS315 (M3, CovS mutant, and Sse of variant complex I), MGAS2221 (M1, wild-type CovRS, and Sse of variant complex I), and MGAS6180 (M28, wild-type CovRS, and Sse of variant complex II). SseM1 immunization significantly increased survival rates of mice in subcutaneous MGAS5005 and intraperitoneal MGAS6180 challenges and showed consistently higher or longer survival in the other challenges. Immunized mice had smaller skin lesion and higher neutrophil responses in subcutaneous infections and lower GAS burdens in spleen, liver, and kidney in most of the challenge experiments than control mice. SseM1 immunization enhanced proinflammatory responses. These data suggest that Sse immunization has a broad benefit against GAS infections that can vary in extent from strain to strain and that the benefit may be due to the immunization-enhanced proinflammatory responses. In particular, immunization with SseM1 can provide protection against M28 GAS infection even though its Sse and SseM1 have significant variations.
RESUMEN
Alterations in placental transport may contribute to abnormal fetal intrauterine growth in pregnancies complicated by diabetes, but it is not clear whether the placental amino acid transport system is altered in diabetic pregnancies. We therefore studied the changes in the expressions of placental amino acid transporters in a rat model of diabetes induced by streptozotocin, and tested the effects of hyperglycemia on trophoblast amino acid transporter in vitro. Our results showed that the expressions for key isoforms of system L amino acid transporters were significantly reduced in the placentas of streptozotocin-induced diabetic pregnant rats, which was associated with the decreased birthweight in the rats. A decreased placental efficiency and decreased placental mammalian target of rapamycin (mTOR) complex 1 (mTORC1) activity were also found in the rat model. In addition, hyperglycemia in vitro could inhibit amino acid transporter expression and mTORC1 activity in human trophoblast. Inhibition of mTORC1 activity led to reduced amino acid transporter expression in placental trophoblast. We concluded that reduced placental mTORC1 activity during pregnancy resulted in decreased placental amino acid transporter expression and, subsequently, contributed to fetal intrauterine growth restriction in pregnancies complicated with diabetes.
Asunto(s)
Sistema de Transporte de Aminoácidos A/metabolismo , Sistema de Transporte de Aminoácidos L/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Retardo del Crecimiento Fetal/fisiopatología , Diana Mecanicista del Complejo 1 de la Rapamicina/biosíntesis , Placenta/fisiopatología , Animales , Línea Celular , Femenino , Retardo del Crecimiento Fetal/genética , Humanos , Embarazo , Ratas , Ratas Sprague-Dawley , EstreptozocinaRESUMEN
BACKGROUND: Degeneration of ovarian function is an obvious feature of female aging. In addition, studies have shown that autophagy decreases with age, and DNA methylation is a hallmark epigenetic pattern during aging. However, it is not clear whether the expression and DNA methylation of autophagy genes are involved in the declines in ovarian function that occur during aging. RESULTS: Three groups of rats were used: 6-month-old (6 M) rats, 12-month-old (12 M) rats and 24-month-old (24 M) rats. Serum E2 levels and the mRNA and protein expression levels of Atg5, Atg12, Atg16L, Beclin1 and Lc3B were significantly decreased in aged rats. In addition, the methylation levels of the Atg5 gene were significantly increased in aged rats. The expression of the Dnmt1 and Dnmt2 genes decreased with aging; however, the expression of the Dnmt3A and Dnmt3B genes gradually increased with aging. CONCLUSIONS: Decreased autophagic activity was involved in the declines in ovarian function in aging rats. Upregulation of the DNA methyltransferases Dnmt3A and Dnmt3B may have led to methylation of the autophagy genes Atg5 and Lc3B to ultimately cause the observed decreases in autophagic activity.