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1.
J Ethnopharmacol ; 329: 118157, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38588987

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus mongholicus Bunge (AMB) is a herb with wide application in traditional Chinese medicine, exerting a wealth of pharmacological effects. AMB has been proven to have an evident therapeutic effect on ischemic cerebrovascular diseases, including cerebral ischemia-reperfusion injury (CIRI). However, the specific mechanism underlying AMB in CIRI remains unclear. AIM OF THE STUDY: This study aimed to investigate the potential role of AMB in CIRI through a comprehensive approach of network pharmacology and in vivo experimental research. METHODS: The intersection genes of drugs and diseases were obtained through analysis of the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database and Gene Expression Omnibus (GEO) database. The protein-protein interaction (PPI) network was created through the string website. Meanwhile, the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was carried out using R studio, and thereafter the key genes were screened. Then, the molecular docking prediction was made between the main active ingredients and target genes, and hub genes with high binding energy were obtained. In addition, molecular dynamic (MD) simulation was used to validate the result of molecular docking. Based on the results of network pharmacology, we used animal experiments to verify the predicted hub genes. First, the rat middle cerebral artery occlusion and reperfusion (MACO/R) model was established and the effective dose of AMB in CIRI was determined by behavioral detection and 2,3,5-Triphenyltetrazolium chloride (TTC) staining. Then the target proteins corresponding to the hub genes were measured by Western blot. Moreover, the level of neuronal death was measured using hematoxylin and eosin (HE) and Nissl staining. RESULTS: Based on the analysis of the TCMSP database and GEO database, a total of 62 intersection target genes of diseases and drugs were obtained. The KEGG enrichment analysis showed that the therapeutic effect of AMB on CIRI might be realized through the advanced glycation endproduct-the receptor of advanced glycation endproduct (AGE-RAGE) signaling pathway in diabetic complications, nuclear factor kappa-B (NF-κB) signaling pathway and other pathways. Molecular docking results showed that the active ingredients of AMB had good binding potential with hub genes that included Prkcb, Ikbkb, Gsk3b, Fos and Rela. Animal experiments showed that AWE (60 g/kg) could alleviate CIRI by regulating the phosphorylation of PKCß, IKKß, GSK3ß, c-Fos and NF-κB p65 proteins. CONCLUSION: AMB exerts multi-target and multi-pathway effects against CIRI, and the underlying mechanism may be related to anti-apoptosis, anti-inflammation, anti-oxidative stress and inhibiting calcium overload.


Asunto(s)
Planta del Astrágalo , Medicamentos Herbarios Chinos , Simulación del Acoplamiento Molecular , Farmacología en Red , Mapas de Interacción de Proteínas , Ratas Sprague-Dawley , Daño por Reperfusión , Animales , Daño por Reperfusión/tratamiento farmacológico , Planta del Astrágalo/química , Masculino , Ratas , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Simulación de Dinámica Molecular
2.
Zool Res ; 45(2): 355-366, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38485505

RESUMEN

Testosterone is closely associated with lipid metabolism and known to affect body fat composition and muscle mass in males. However, the mechanisms by which testosterone acts on lipid metabolism are not yet fully understood, especially in teleosts. In this study, cyp17a1-/- zebrafish ( Danio rerio) exhibited excessive visceral adipose tissue (VAT), lipid content, and up-regulated expression and activity of hepatic de novo lipogenesis (DNL) enzymes. The assay for transposase accessible chromatin with sequencing (ATAC-seq) results demonstrated that chromatin accessibility of DNL genes was increased in cyp17a1-/- fish compared to cyp17a1+/+ male fish, including stearoyl-CoA desaturase ( scd) and fatty acid synthase ( fasn). Androgen response element (ARE) motifs in the androgen signaling pathway were significantly enriched in cyp17a1+/+ male fish but not in cyp17a1-/- fish. Both androgen receptor ( ar)-/- and wild-type (WT) zebrafish administered with Ar antagonist flutamide displayed excessive visceral adipose tissue, lipid content, and up-regulated expression and activity of hepatic de novo lipogenesis enzymes. The Ar agonist BMS-564929 reduced the content of VAT and lipid content, and down-regulated acetyl-CoA carboxylase a ( acaca), fasn, and scd expression. Mechanistically, the rescue effect of testosterone on cyp17a1-/- fish in terms of phenotypes was abolished when ar was additionally depleted. Collectively, these findings reveal that testosterone inhibits lipid deposition by down-regulating DNL genes via Ar in zebrafish, thus expanding our understanding of the relationship between testosterone and lipid metabolism in teleosts.


Asunto(s)
Andrógenos , Lipogénesis , Masculino , Animales , Andrógenos/farmacología , Lipogénesis/genética , Pez Cebra/genética , Testosterona , Lípidos , Transducción de Señal , Cromatina
3.
Cancer Immunol Res ; 12(3): 350-362, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38113030

RESUMEN

The existing T cell-centered immune checkpoint blockade therapies have been successful in treating some but not all patients with cancer. Immunosuppressive myeloid cells, including myeloid-derived suppressor cells (MDSC), that inhibit antitumor immunity and support multiple steps of tumor development are recognized as one of the major obstacles in cancer treatment. Leukocyte Ig-like receptor subfamily B3 (LILRB3), an immune inhibitory receptor containing tyrosine-based inhibitory motifs (ITIM), is expressed solely on myeloid cells. However, it is unknown whether LILRB3 is a critical checkpoint receptor in regulating the activity of immunosuppressive myeloid cells, and whether LILRB3 signaling can be blocked to activate the immune system to treat solid tumors. Here, we report that galectin-4 and galectin-7 induce activation of LILRB3 and that LILRB3 is functionally expressed on immunosuppressive myeloid cells. In some samples from patients with solid cancers, blockade of LILRB3 signaling by an antagonistic antibody inhibited the activity of immunosuppressive myeloid cells. Anti-LILRB3 also impeded tumor development in myeloid-specific LILRB3 transgenic mice through a T cell-dependent manner. LILRB3 blockade may prove to be a novel approach for immunotherapy of solid cancers.


Asunto(s)
Células Supresoras de Origen Mieloide , Neoplasias , Ratones , Animales , Humanos , Células Mieloides , Neoplasias/terapia , Linfocitos T , Receptores Inmunológicos , Microambiente Tumoral , Antígenos CD
4.
Microvasc Res ; 151: 104600, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37666318

RESUMEN

Atrial fibrillation (AF) is a cardiac disease characterized by disordered atrial electrical activity. Atrial inflammation and fibrosis are involved in AF progression. Costunolide (COS) is a sesquiterpene lactone containing anti-inflammatory and anti-fibrotic activities. This study aims to explore the underlying mechanisms by which COS protects against AF. Male C57BL/6 mice (8- to 10-week-old) were infused with angiotensin (Ang) II for 3 weeks. Meanwhile, different doses of COS (COS-L: 10 mg/kg, COS-H: 20 mg/kg) were administered to mice by intragastric treatment. The results showed irregular and rapid heart rates in Ang II-treated mice. Moreover, the levels of inflammatory cytokines and fibrotic factors were elevated in mice. COS triggered a reduction of Ang II-induced inflammation and fibrosis, which conferred a protective effect. Mechanistically, mitochondrial dysfunction with mitochondrial respiration inhibition and aberrant ATP levels were observed after Ang II treatment. Moreover, Ang-II-induced excessive reactive oxygen species caused oxidative stress, which was further aggravated by inhibiting Nrf2 nuclear translocation. Importantly, COS diminished these Ang-II-mediated effects in mice. In conclusion, COS attenuated inflammation and fibrosis in Ang-II-treated mice by alleviating mitochondrial dysfunction and oxidative stress. Our findings represent a potential therapeutic option for AF treatment.


Asunto(s)
Fibrilación Atrial , Enfermedades Mitocondriales , Sesquiterpenos , Ratones , Masculino , Animales , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/prevención & control , Angiotensina II/farmacología , Ratones Endogámicos C57BL , Sesquiterpenos/efectos adversos , Estrés Oxidativo , Mitocondrias/metabolismo , Fibrosis , Inflamación/tratamiento farmacológico , Inflamación/prevención & control
5.
Int Wound J ; 21(3): e14515, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38009983

RESUMEN

Proximal humerus fractures are common in clinical practice, and there are relatively a few studies on postoperative incision infections of such fractures. The purpose of this study was to explore the risk factors for surgical site infection (SSI) after internal fixation in patients with closed proximal humerus fractures. Patients with closed proximal humerus fractures who underwent surgery from January 2016 to January 2022 were retrospectively analysed. Cases with superficial or deep infections within 3 months after surgery were in the infection group and the remaining cases were in the non-infection group. The types of pathogenic bacteria in the infection group were analysed. The potential risk factors for SSI in all patients were recorded: (1) patient-related factors: gender, age, body mass index (BMI), smoking, comorbidities; (2) trauma-related factors: mechanism of injury, Injury Severity Score, visual analogue scale, fracture type, soft tissue condition and combined dislocation; (3) laboratory-related indexes: haemoglobin, albumin; (4) surgery-related factors: time from injury to surgery, American Society of Anesthesiologists anaesthesia classification, surgical time, fixation mode, intraoperative blood loss, suture method, bone graft and postoperative drainage. The risk factors for the occurrence of SSI were analysed using univariate analysis and multivariate logistic regression. The incidence of SSI was 15.7%. The most common bacterium in the infection group was Staphylococcus aureus. High BMI (p = 0.033), smoking (p = 0.030), an increase in mean time from injury to definitive surgery (p = 0.013), and prolonged surgical time (p = 0.044) were independent risk factors for the development of SSI after closed proximal humeral fractures. In patients with closed proximal humerus fractures, weight loss, perioperative smoking cessation, avoidance of delayed surgery, and shorter surgical time may be beneficial in reducing the incidence of SSI.

6.
J Cardiovasc Pharmacol Ther ; 28: 10742484231185252, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37403470

RESUMEN

Purpose: The molecular etiology of atrial fibrillation (AF) and its treatment are poorly understood. AF involves both electrical and structural features. Vericiguat can ameliorate cardiac remodeling in heart failure. The effects of vericiguat on AF, however, are unclear. Here, the actions of vericiguat on atrial structural and electrical remodeling in AF and its possible mechanisms were investigated. Methods and Results: Thirty-six rabbits were randomly allocated to four groups, namely, sham, RAP (pacing with 600 beats/min over three weeks), vericiguat-treated (three weeks' pacing plus daily oral dose of 1.5 mg/kg of vericiguat), and vericiguat-treated only. HL-1 cells received rapid pacing with or without vericiguat. Parameters including electrophysiology, echocardiography, histology, Ca2+ levels, and ICaL density, as well as levels of TRPC6, CaN, NFAT4, p-NFAT4, Cav1.2, collagen I, collagen III, and ST2 were measured. Significant changes of above proteins expression level, circulating biochemical indices, Ca2+ concentrations, and ICaL density in both animals and cell models, these effects were significantly restored by vericiguat. Vericiguat also reversed the enlarged atrium and significantly reduced myocardial fibrosis, together with preventing reduced atrial effective refractory periods (AERPs) and AF induction rate. Conclusion: Vericiguat thus ameliorated AF-associated structural and electrical remodeling. These findings suggest the potential of vericiguat for treating AF.


Asunto(s)
Fibrilación Atrial , Remodelación Atrial , Animales , Conejos , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/prevención & control , Fibrilación Atrial/etiología , Atrios Cardíacos , Colágeno/metabolismo , Modelos Animales de Enfermedad , Estimulación Cardíaca Artificial/efectos adversos , Estimulación Cardíaca Artificial/métodos
7.
Front Med (Lausanne) ; 10: 1171463, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37359012

RESUMEN

Background: The coexistence of Crohn's disease (CD) and acute appendicitis (AA) is rare. In this situation, therapeutic experience is lacking and the strategy is paradoxical and intractable. Appendectomy is the gold standard for the treatment of AA whereas a nonsurgical approach is recommended for CD. Case summary: A 17-year-old boy was hospitalized for right lower abdominal pain with fever of 3 days. He had the CD for 8 years. Two years ago, he underwent surgery for anal fistula with the complication of CD. His temperature was elevated at 38.3°C at admission. On physical examination, there was McBurney tenderness with mild rebound tenderness. Abdominal ultrasonography showed that the appendix was notably enlarged and dilated at 6.34 cm long and 2.76 cm wide. These findings were suggestive of uncomplicated AA in this patient with active CD. Endoscopic retrograde appendicitis therapy (ERAT) was performed. The patient had complete pain relief immediately after the procedure without tenderness in the right lower abdomen. During 18 mo follow-up, he had no more attacks in his right lower abdomen. Conclusion: ERAT was effective and safe in a CD patient with coexisting AA. Such cases can avoid surgery and its-related complications.

8.
Zhongguo Gu Shang ; 36(5): 459-64, 2023 May 25.
Artículo en Chino | MEDLINE | ID: mdl-37211940

RESUMEN

OBJECTIVE: To investigate the outcome of lateral femoral notch (LFN) after early anterior cruciate ligament (ACL) reconstruction and evaluate the recovery of knee joint function after the operation. METHODS: The clinical data of 32 patients who underwent early ACL reconstruction from December 2015 to December 2019 were retrospectively analyzed. The study included 18 males and 14 females, aged 16 to 54 years old, with an average age of (25.39±2.82) years. The body mass index (BMI) of the patients ranged from 20 to 30 kg/cm2, with an average of (26.15±3.09) kg/cm2. Among them, 6 cases were caused by traffic accidents, 19 by exercise, and 7 by the crush of heavy objects. MRI of all patients showed LFN depth was more than 1.5 mm after injury, and no intervention for LFN was performed during surgery. Preoperative and postoperative depth, area, and volume of LFN defects were observed by MRI data. International Cartilage Repair Society (ICRS) score, Lysholm score, Tegner activity levels, and knee injury and osteoarthritis outcome score (KOOS) were analyzed before and after the operation. RESULTS: All patients were followed up from 2 to 6 years with an average of (3.28±1.12) years. There was no significant difference in the defect depth of LFN from (2.31±0.67) mm before the operation to (2.53±0.50) mm at follow-up (P=0.136). The defect area of LFN was decreased from (207.55±81.01)mm2 to (171.36±52.69)mm2 (P=0.038), and the defect volume of LFN was decreased from (426.32±176.54) mm3 to (340.86±151.54)mm3 (P=0.042). The ICRS score increased from (1.51±0.34) to (2.92±0.33) (P<0.001), the Lysholm score increased from (35.37±10.54) to (94.46±8.45) (P<0.001), and the Tegner motor score increased from (3.45±0.94) to (7.56±1.28), which was significantly higher than that of the preoperative data (P<0.001). The KOOS score of the final follow-up was 90.42±16.35. CONCLUSION: With the increase of recovery time after anterior cruciate ligament reconstruction, the defect area and volume of LFN decreased gradually, but the defect depth remained unchanged. The knee joint function of the patients significantly improved. The cartilage of the LFN defect improved, but the repair effect was not good.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Masculino , Femenino , Humanos , Adulto Joven , Adulto , Adolescente , Persona de Mediana Edad , Lesiones del Ligamento Cruzado Anterior/cirugía , Estudios Retrospectivos , Imagen por Resonancia Magnética , Fémur/cirugía , Resultado del Tratamiento , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía
9.
Int J Nanomedicine ; 18: 2447-2463, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37192892

RESUMEN

Introduction: Benzalkonium chloride (BAC) is widely employed as a preservative in eye drops, which will cause the death of corneal epithelial cells due to ROS production, DNA strand breakage, and mitochondrial dysfunction, resulting in dry eye disease (DED)-like changes in ocular surface tissues. In this study, Melatonin (MT) liposomes (TAT-MT-LIPs) designed by loading MT into TAT-modified liposomes have been developed, characterized, and used for inhibiting BAC-induced DED (BAC-DED). Methods: The TAT was chemically grafted onto the Mal-PEG2000-DSPE by Michael's addition between the sulfhydryl group in TAT and the maleimide group in Mal-PEG2000-DSPE. TAT-MT-LIPs were prepared using film dispersion followed by the extrusion method and topically treated in rats once a day. BAC-DED was induced in rats by topical administration with 0.2% BAC twice daily. Defects, edema, and inflammation of the corneas, as well as IOP, were examined. Histologic analyses of corneas were performed to assess the change of mitochondrial DNA oxidation and NLRP3/Caspase-1/GSDMD signaling transduction. Results: After topical administration, TAT-MT-LIPs significantly alleviated DED-clinical symptoms of experimental animals by inhibiting tissue inflammation and preventing the loss of the corneal epithelium and conjunctival goblet cells. Our data suggested continuous ocular surface exposure of BAC-induced NLRP3/Caspase-1/GSDMD mediated corneal epithelium pyroptosis, which was not reported before. BAC caused substantial mt-DNA oxidation, which promoted the transduction of NLRP3/Caspase-1/GSDMD and consequent corneal epithelium pyroptosis. TAT-MT-LIPs could efficiently suppress the BAC-induced corneal epithelium pyroptosis and inflammation by inhibiting mt-DNA oxidation and the subsequent signal transmission. Conclusion: NLRP3/Caspase-1/GSDMD mediated corneal epithelium pyroptosis is involved in the development of BAC-DED. The present study provided new insights into the adverse effects of BAC, which can serve as a new target for protecting corneal epithelium when applying BAC as a preservative in eye drops. The developed TAT-MT-LIPs can efficiently inhibit BAC-DED and give great potential to be developed as a new DED treatment.


Asunto(s)
Síndromes de Ojo Seco , Epitelio Corneal , Melatonina , Ratas , Animales , Epitelio Corneal/patología , Compuestos de Benzalconio/toxicidad , Caspasa 1 , Piroptosis , Proteína con Dominio Pirina 3 de la Familia NLR , Liposomas/farmacología , Melatonina/farmacología , Inflamación/patología , Síndromes de Ojo Seco/inducido químicamente , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/patología , Soluciones Oftálmicas/farmacología
12.
Adv Healthc Mater ; 12(15): e2202826, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36871175

RESUMEN

″Nano-metamaterials″, rationally designed novel class metamaterials with multilevel microarchitectures and both characteristic sizes and whole sizes at the nanoscale, are introduced into the area of drug delivery system (DDS), and the relationship between release profile and treatment efficacy at the single-cell level is revealed for the first time. Fe3+ -core-shell-corona nano-metamaterials (Fe3+ -CSCs) are synthesized using a dual-kinetic control strategy. The hierarchical structure of Fe3+ -CSCs, with a homogeneous interior core, an onion-like shell, and a hierarchically porous corona. A novel polytonic drug release profile occurred, which consists of three sequential stages: burst release, metronomic release, and sustained release. The Fe3+ -CSCs results in overwhelming accumulation of lipid reactive oxygen species (ROS), cytoplasm ROS, and mitochondrial ROS in tumor cells and induces unregulated cell death. This cell death modality causes cell membranes to form blebs, seriously corrupting cell membranes to significantly overcome the drug-resistance issues. It is first demonstrated that nano-metamaterials of well-defined microstructures can modulate drug release profile at the single cell level, which in turn alters the downstream biochemical reactions and subsequent cell death modalities. This concept has significant implications in the drug delivery area and can serve to assist in designing potential intelligent nanostructures for novel molecular-based diagnostics and therapeutics.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanoestructuras , Liberación de Fármacos , Especies Reactivas de Oxígeno/metabolismo , Nanoestructuras/química
13.
Adv Sci (Weinh) ; 10(4): e2205595, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36377475

RESUMEN

Increasingly intricate in their multilevel multiscale microarchitecture, metamaterials with unique physical properties are challenging the inherent constraints of natural materials. Their applicability in the nanomedicine field still suffers because nanomedicine requires a maximum size of tens to hundreds of nanometers; however, this size scale has not been achieved in metamaterials. Therefore, "nano-metamaterials," a novel class of metamaterials, are introduced, which are rationally designed materials with multilevel microarchitectures and both characteristic sizes and whole sizes at the nanoscale, investing in themselves remarkably unique and significantly enhanced material properties as compared with conventional nanomaterials. Microarchitectural regulation through conventional thermodynamic strategy is limited since the thermodynamic process relies on the frequency-dependent effective temperature, Teff (ω), which limits the architectural regulation freedom degree. Here, a novel dual-kinetic control strategy is designed to fabricate nano-metamaterials by freezing a high-free energy state in a Teff (ω)-constant system, where two independent dynamic processes, non-solvent induced block copolymer (BCP) self-assembly and osmotically driven self-emulsification, are regulated simultaneously. Fe3+ -"onion-like core@porous corona" (Fe3+ -OCPCs) nanoparticles (the products) have not only architectural complexity, porous corona and an onion-like core but also compositional complexity, Fe3+ chelating BCP assemblies. Furthermore, by using Fe3+ -OCPCs as a model material, a microstructure-biological performance relationship is manifested in nano-metamaterials.

14.
J Mol Histol ; 54(1): 55-65, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36417034

RESUMEN

Circular RNAs (circRNAs) have been shown to be associated with cardiac fibrosis. Atrial fibrosis is an important pathophysiological event in the progression of atrial fibrillation (AF). Although a novel circRNA calmodulin binding transcription activator 1 (circCAMTA1) has been reported to be related with the development of AF, the detailed molecular mechanisms remain largely unknown. In this study, we found that circCAMTA1 was upregulated in atrial muscle tissues of AF patients and angiotensin-II (Ang-II)-treated human atrial fibroblasts (HAFs). Moreover, circCAMTA1 expression was positively correlated with the expression of collagen (I and III) and α-SMA in atrial muscle tissues of AF patients. In vitro experiments, knockdown of circCAMTA1 significantly suppressed Ang-II-induced HAFs proliferation and reduced the expression of atrial fibrosis-associated genes, but overexpression of circCAMTA1 exhibited opposite results. In vivo experiments, circCAMTA1 knockdown ameliorated Ang-II-induced atrial fibrosis by reducing AF incidence, AF duration, and collagen synthesis. Functionally, circCAMTA1 facilitated Ang-II-induced atrial fibrosis in vitro and in vivo via downregulating the inhibitory effect of miR-214-3p on transforming growth factor ß receptor 1 (TGFBR1) expression. In conclusions, circCAMTA1 knockdown alleviated atrial fibrosis through downregulating TGFBR1 expression intermediated by miR-214-3p in AF, suggesting circCAMTA1/miR-214-3p/TGFBR1 axis may be a novel therapeutic target for AF treatment in clinic.


Asunto(s)
Fibrilación Atrial , MicroARNs , Humanos , Fibrilación Atrial/genética , Fibrilación Atrial/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , MicroARNs/metabolismo , Fibrosis , Colágeno/metabolismo , Fibroblastos/metabolismo , Angiotensina II/farmacología , Angiotensina II/metabolismo
15.
J Phys Chem Lett ; 13(51): 12082-12089, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36546645

RESUMEN

How to resolve contradictions between the nanoscale size and high saturation magnetization (Ms) remains one of the scientific challenges in nanoscale magnetism as the theoretical optimal Ms of nanocrystals is compromised by the surface spin disorder. Here, we proposed a novel nanotechnology solution, heterointerface constructions of exchange-coupling core-shell nanocrystals, to rearrange the surface spin for the enhancement of Ms of nanomagnetic materials. As a demonstration of this principle, single-interface coupling FePt@Fe3-δO4 core/shell nanocrystals and multi-interface coupling FePt@Fe3-δO4@MFe2O4 (M = Mn or Co) core/shell/shell nanocrystals were synthesized. The simulated and experimental results demonstrated that constructing coupling heterointerfaces orientates the overall magnetic moment, ultimately enhancing the Ms of nanomagnetic materials. Moreover, this work first demonstrated that the origin of coupling heterointerfaces arose from mismatched lattices rather than chemical composition mismatch at the core-shell interfaces, thus providing both a solution to unite different mechanisms and an explanation to explain the exchange coupling at heterointerfaces.

16.
Biomater Adv ; 138: 212936, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35913229

RESUMEN

Traumatic optic neuropathy (TON) is the major contributor to optic nerve damage, where the retinal ganglion cells (RGCs) are substantially lost. However, the underlying pathological mechanisms for these conditions remain largely elusive. Present work conducted a study on TON rat model, where the iron-dependent cyclooxygenase-2 (COX-2) overexpression and lipid peroxidation were observed in RGCs, suggesting ferroptosis, an iron-dependent non-apoptotic cell death, is involved in TON-induced death of RGCs. Hence, the newly formulated hyaluronic acid (HA)-based deferoxamine (DFO) nanoparticles (DFO-NPs) were intravitreally administrated in the rat model. It was hypothesized that the effective delivery of DFO, iron chelator, to the RGCs might rescue RGC ferroptosis from TON-induced injury. Also, since DFO is poor in bioavailability and of very short half-life in vivo, its safe and efficient intravitreal delivery is critical. Therefore, DFO-NPs were prepared by chemical grafting DFO onto HA molecules, and then crosslinking them in microemulsion bubbles for nanoparticles formulation. The nanoparticles were highly accumulated around the ganglionic cells and DFO uptake was increased in RGCs, accompanied by the significantly inhibited the overexpression of COX-2 and inactivation of glutathione peroxidase 4 (GPX4). These results indicate that DFO-NPs acted as an effective ferroptosis inhibitor, for the prevention of TON-induced RGC death. The current study provides new insights into the underlying mechanism of TON-induced RGC death, which may help to explore a novel strategy for the treatment of TON.


Asunto(s)
Ferroptosis , Nanopartículas , Traumatismos del Nervio Óptico , Animales , Ciclooxigenasa 2/metabolismo , Deferoxamina/farmacología , Hierro/metabolismo , Nanopartículas/uso terapéutico , Traumatismos del Nervio Óptico/tratamiento farmacológico , Ratas , Células Ganglionares de la Retina
17.
Front Genet ; 13: 887217, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35783267

RESUMEN

The NB-ARC (nucleotide-binding adaptor shared by APAF-1, R proteins, and CED-4) gene family plays a critical role in plant development. However, our understanding of the mechanisms of how NB-ARC genes regulate plant development in the plant panicle is still limited. Here, we subjected 258 NB-ARC genes in rice to genome-wide analysis to characterize their structure, function, and expression patterns. The NB-ARC genes were classified into three major groups, and group II included nine subgroups. Evolutionary analysis of NB-ARC genes in a dicotyledon plant (Arabidopsis thaliana) and two monocotyledonous plants (Oryza sativa L. and Triticum aestivum) indicated that homologous genome segments were conserved in monocotyledons and subjected to weak positive selective pressure during evolution. Dispersed and proximal replication events were detected. Expression analysis showed expression of most NB-ARC genes in roots, panicles, and leaves, and regulation at the panicle development stage in rice Ce253. The GNP12 gene encodes RGH1A protein, which regulates rice yield according to panicle length, grain number of panicle, and grain length, with eight major haplotypes. Most members of NB-ARC protein family are predicted to contain P-loop conserved domains and localize on the membrane. The results of this study will provide insight into the characteristics and evolution of NB-ARC family and suggest that GNP12 positively regulates panicle development.

18.
Angew Chem Int Ed Engl ; 61(33): e202202559, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35607251

RESUMEN

The heterogeneity in biofilms is a major challenge in biofilm therapies due to different susceptibility of bacteria and extracellular polymeric substances (EPS) to antibacterial agents. Here, we describe a therapeutic strategy that overcame biofilm heterogeneity, where antibacterial agent (NO) and EPS dispersant (reactive oxygen species (ROS)-inducing Fe3+ ) were separately loaded in the yolk and shell compartment of a yolk-shell nanoplatform. Compared with traditional combinational chemotherapies which suffer from inconsistent pharmacokinetics profiles, this strategy drew on the pharmacokinetic complementarity of ROS and NO, where ROS with a short diffusion distance and a high redox potential corrupted the EPS, facilitating NO, which has a long diffusion distance and a broad antimicrobial spectrum, to penetrate the biofilm and eliminate the resident bacteria. Additionally, the construction of a three-dimensional spherical biofilm model is novel and clinically relevant.


Asunto(s)
Antiinfecciosos , Biopelículas , Bacterias , Matriz Extracelular de Sustancias Poliméricas , Especies Reactivas de Oxígeno
19.
Front Pharmacol ; 13: 813272, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35370645

RESUMEN

Background and Purpose: Atrial metabolic remodeling plays a critical role in the pathogenesis of atrial fibrillation (AF). Sirtuin3 (Sirt3) plays an important role in energy homeostasis. However, the effect of Sirt3 agonist Honokiol (HL) on AF is unclear. Therefore, the aim of this study is to determine the effect of HL on atrial metabolic remodeling in AF and to explore possible mechanisms. Experimental Approach: irt3 and glycogen deposition in left atria of AF patients were examined. Twenty-one rabbits were divided into sham, P (pacing for 3 weeks), P + H treatment (honokiol injected with pacing for 3 weeks). The HL-1 cells were subjected to rapid pacing at 5 Hz for 24 h, in the presence or absence of HL and overexpression or siRNA of Sirt3 by transfection. Metabolic factors, circulating metabolites, atrial electrophysiology, ATP level, and glycogens deposition were detected. Acetylated protein and activity of its enzymes were detected. Key Results: Sirt3 was significantly down-regulated in AF patients and rabbit/HL-1cell model, resulting in the abnormal expression of its downstream metabolic key factors, which were significantly restored by HL. Meanwhile, AF induced an increase of the acetylation level in long-chain acyl-CoA dehydrogenase (LCAD), AceCS2 and GDH, following decreasing of activity of it enzymes, resulting in abnormal alterations of metabolites and reducing of ATP, which was inhibited by HL. The Sirt3 could regulate acetylated modification of key metabolic enzymes, and the increase of Sirt3 rescued AF induced atrial metabolic remodeling. Conclusion and Implications: HL inhibited atrial metabolic remodeling in AF via the Sirt3 pathway. The present study may provide a novel therapeutical strategy for AF.

20.
Blood ; 139(21): 3204-3221, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35259210

RESUMEN

Bone marrow-derived mesenchymal stem cells (BMSCs) support bone formation and constitute the stromal niche in regulating hematopoietic stem cells (HSCs). Stromal niche dysfunction affects HSC engraftment during transplantation; however, the underlying mechanisms remain elusive. In the present study, we found that all-trans retinoic acid (ATRA) and inflammation stress upregulated retinoic acid-inducible gene I (RIG-I) in BMSCs. Excess RIG-I expression damaged the clonogenicity, bone-forming ability of BMSCs and particularly their stromal niche function that supports HSC expansion in vitro and engraftment in vivo. Mechanistically, RIG-I elevation promoted the degradation of NRF2, a checkpoint for antioxidant cellular response, by altering the RIG-I-Trim25-Keap1-NRF2 complex, leading to reactive oxygen species (ROS) accumulation and BMSC damage. Genetic inhibition of RIG-I sustained NRF2 protein levels and reduced ROS levels in ATRA-treated BMSCs, thus preserving their clonogenicity, bone-forming ability, and stromal niche function in supporting HSC engraftment in mice. More importantly, RIG-I inhibition recovered the ATRA-treated stromal niche function to enhance HSC engraftment and emergency myelopoiesis for innate immunity against the bacterium Listeria monocytogenes during transplantation. Overall, we identified a noncanonical role of RIG-I in the regulation of the stromal niche for HSC transplantation.


Asunto(s)
Trasplante de Médula Ósea , Proteína 58 DEAD Box/metabolismo , Factor 2 Relacionado con NF-E2 , Animales , Células Madre Hematopoyéticas/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ratones , Especies Reactivas de Oxígeno/metabolismo , Nicho de Células Madre/fisiología
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