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Magnesium hydroxide (MgH2) has a broad application prospect in solid hydrogen storage, but the associated higher dehydrogenation temperature and undesirable cycling capacity limit its large-scale application. In this study, a BaCrO4 nanocatalyst prepared via a wet chemistry method was added to MgH2 to achieve better kinetic and thermodynamic performances. Kinetic tests suggested that the onset hydrogen desorption temperature was decreased for milled MgH2 from 390 °C to below 280 °C after the introduction of a 5 wt% BaCrO4 nanocatalyst and the maximum dehydrogenation amount was up to 6.32 wt%. With regard to hydrogen absorption, MgH2 incorporated with 10 wt% BaCrO4 could fully absorb 5.78 wt% H2 within 10 min at 300 °C and recharge 3.1 wt% H2 at a low temperature of 250 °C. In comparison, the hydrogen uptake amounts for MgH2 under the same conditions were only 3.98 wt% and 1.52 wt%. With regard to hydrogen desorption, 5 wt% BaCrO4-modified MgH2 could discharge 4.25 wt% H2 within 10 min at 325 °C and 4.81 wt% H2 at 300 °C, while MgH2 could not dehydrogenate at 300 °C. Meanwhile, only 5% of the performance decayed for 5 wt% BaCrO4-modified MgH2 during ten cycles. Dehydrogenation E a reduced to 106.75 kJ mol-1 in contrast to 156.55 kJ mol-1 for MgH2. In addition, DFT results verified that the BaCrO4 nanocatalyst reduced the band gap from 2.78 eV to 2.16 eV to improve the thermodynamic property of MgH2 and contributed to the decrease in the dehydrogenation energy barrier from 2.27 eV to 1.54 eV. This work provides an insight into the performance of ternary transition metal nanocatalysts for MgH2 hydrogen storage systems.
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Self-stabilized precipitation (2SP) polymerization enables the facile synthesis of uniform polymer spheres with sizes ranging from 100 nm to 3 µm, without the need for stabilizers or cross-linkers, even at high monomer concentrations of up to 30%. While previous studies have extensively explored the influence of reaction conditions on the size and uniformity of microsphere products, their impact on particle morphology has received less attention. In this work, we demonstrate that particle growth in 2SP polymerization primarily occurs via the adsorption of polymers from the solution onto the particle surface, leading to an increase in particle circularity and a smoother surface. The surface roughness of the particles is controlled by the aggregation of primary particles and the subsequent polymer adsorption process during the growth stage. Smooth microspheres are obtained under conditions of moderate monomer concentration, high initiator concentration, and elevated temperature. Our findings highlight the significance of the particle growth process in determining particle morphology in addition to the well-established role of polymer-solvent interactions during precipitation polymerization.
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Idiopathic pulmonary fibrosis (IPF) is a lethal progressive fibrotic lung disease. The development of IPF involves different molecular and cellular processes, and recent studies indicate that lactate plays a significant role in promoting the progression of the disease. Nevertheless, the mechanism by which lactate metabolism is regulated and the downstream effects remain unclear. The molecular chaperone CCT6A performs multiple functions in a variety of biological processes. Our research has identified a potential association between CCT6A and serum lactate levels in IPF patients. Herein, we found that CCT6A was highly expressed in type 2 alveolar epithelial cells (AEC2s) of fibrotic lung tissues and correlated with disease severity. Lactate increases the accumulation of lipid droplets in epithelial cells. CCT6A inhibits lipid synthesis by blocking the production of lactate in AEC2s and alleviates bleomycin-induced pulmonary fibrosis in mice. In addition, our results revealed that CCT6A blocks HIF-1α-mediated lactate production by driving the VHL-dependent ubiquitination and degradation of HIF-1α and further inhibits lipid accumulation in fibrotic lungs. In conclusion, we propose that there is a pivotal regulatory role of CCT6A in lactate metabolism in pulmonary fibrosis, and strategies aimed at targeting these key molecules could represent potential therapeutic approaches for pulmonary fibrosis.
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BACKGROUND: Abnormal lipid metabolism has recently been reported as a crucial signature of idiopathic pulmonary fibrosis (IPF). However, the origin and biological function of the lipid and possible mechanisms of increased lipid content in the pathogenesis of IPF remains undetermined. METHODS: Oil-red staining and immunofluorescence analysis were used to detect lipid accumulation in mouse lung fibrosis frozen sections, Bleomycin-treated human type II alveolar epithelial cells (AECIIs) and lung fibroblast. Untargeted Lipid omics analysis was applied to investigate differential lipid species and identified LysoPC was utilized to treat human lung fibroblasts and mice. Microarray and single-cell RNA expression data sets identified lipid metabolism-related differentially expressed genes. Gain of function experiment was used to study the function of 3-hydroxy-3-methylglutaryl-Coa Synthase 2 (HMGCS2) in regulating AECIIs lipid metabolism. Mice with AECII-HMGCS2 high were established by intratracheally delivering HBAAV2/6-SFTPC- HMGCS2 adeno-associated virus. Western blot, Co-immunoprecipitation, immunofluorescence, site-directed mutation and flow cytometry were utilized to investigate the mechanisms of HMGCS2-mediated lipid metabolism in AECIIs. RESULTS: Injured AECIIs were the primary source of accumulated lipids in response to Bleomycin stimulation. LysoPCs released by injured AECIIs could activate lung fibroblasts, thus promoting the progression of pulmonary fibrosis. Mechanistically, HMGCS2 was decreased explicitly in AECIIs and ectopic expression of HMGCS2 in AECIIs using the AAV system significantly alleviated experimental mouse lung fibrosis progression via modulating lipid degradation in AECIIs through promoting CPT1A and CPT2 expression by interacting with PPARα. CONCLUSIONS: These data unveiled a novel etiological mechanism of HMGCS2-mediated AECII lipid metabolism in the genesis and development of pulmonary fibrosis and provided a novel target for clinical intervention.
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Regulación hacia Abajo , Fibroblastos , Hidroximetilglutaril-CoA Sintasa , Metabolismo de los Lípidos , Ratones Endogámicos C57BL , Animales , Humanos , Masculino , Ratones , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/patología , Bleomicina/toxicidad , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/patología , Hidroximetilglutaril-CoA Sintasa/metabolismo , Hidroximetilglutaril-CoA Sintasa/genética , Hidroximetilglutaril-CoA Sintasa/biosíntesis , Fibrosis Pulmonar Idiopática/metabolismo , Fibrosis Pulmonar Idiopática/patología , Fibrosis Pulmonar Idiopática/genética , Metabolismo de los Lípidos/fisiología , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/genéticaRESUMEN
Cowpea, Vigna unguiculata L. Walp., is a diploid warm-season legume of critical importance as both food and fodder in sub-Saharan Africa. This species is also grown in Northern Africa, Europe, Latin America, North America, and East to Southeast Asia. To capture the genomic diversity of domesticates of this important legume, de novo genome assemblies were produced for representatives of six subpopulations of cultivated cowpea identified previously from genotyping of several hundred diverse accessions. In the most complete assembly (IT97K-499-35), 26,026 core and 4963 noncore genes were identified, with 35,436 pan genes when considering all seven accessions. GO terms associated with response to stress and defense response were highly enriched among the noncore genes, while core genes were enriched in terms related to transcription factor activity, and transport and metabolic processes. Over 5 million single nucleotide polymorphisms (SNPs) relative to each assembly and over 40 structural variants >1 Mb in size were identified by comparing genomes. Vu10 was the chromosome with the highest frequency of SNPs, and Vu04 had the most structural variants. Noncore genes harbor a larger proportion of potentially disruptive variants than core genes, including missense, stop gain, and frameshift mutations; this suggests that noncore genes substantially contribute to diversity within domesticated cowpea.
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Fabaceae , Vigna , Vigna/genética , Genoma de Planta , Genes de Plantas , Fabaceae/genética , Sitios de Carácter CuantitativoRESUMEN
BACKGROUND: It has been demonstrated that circularRNA (circRNAs) plays a critical role in various cancers. While the potential molecular mechanism of circRNAs in the progression of colorectal cancer (CRC) remains uncertain. METHODS: Differentially expressed circRNAs were identified by RNA sequencing. RT-qPCR detected the expression of circ_0009092, miR-665, and NLK in CRC tissues and cells. Functions of circ_0009092 on tumor cell proliferation, migration, and invasion were investigated by a series of in vitro assays. The underlying mechanism of circ_0009092 was explored by bioinformatics analysis, RNA immunoprecipitation (RIP) and luciferase assays. A co-culture assay in vitro was performed to detect the affection of circ_0009092 on macrophage recruitment in the tumor microenvironment (TME). A xenograft mouse model was used to explore the effect of circ_0009092 on tumor growth. RESULTS: Circ_0009092 was downregulated in CRCand predicted a good prognosis. Overexpression of circ_0009092 reduced tumor cell EMT, proliferation, migration, and invasion in vitro and in vivo. Mechanistically, circ_0009092 elevated the NLK expression via sponging miR-665 and suppressed the Wnt/ß-catenin signaling pathway. EIF4EA3 induced circ_0009092 expression in CRC cells. In addition, NLK regulates phosphorylation and O-GlcNAcylation of STAT3 by binding to STAT3, thereby inhibiting CCL2 expression, in which it inhibits macrophage recruitment in the tumor microenvironment (TME). CONCLUSION: EIF4A3 suppressed circ_0009092 biogenesis, whichinhibits CRC progression by sponging miR-665 to downregulate NLK. Circ_0009092/miR-665/NLK suppressed tumor EMT, proliferation, migration, and invasion by acting on the Wnt/ß-catenin signaling pathway. NLK directly interacted with STAT3 and decreased the CCL2 expression, inhibiting the recruitment of tumor-associated macrophages (TAMs) in the TME. Our study provided novel insights into the roles of circ_0009092 as a novel promising prognostic and therapeutic target in CRC.
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Neoplasias Colorrectales , MicroARNs , Humanos , Animales , Ratones , ARN Circular/genética , ARN Circular/metabolismo , Macrófagos Asociados a Tumores/metabolismo , Microambiente Tumoral/genética , Línea Celular Tumoral , Neoplasias Colorrectales/patología , MicroARNs/genética , MicroARNs/metabolismo , Vía de Señalización Wnt , Proliferación Celular/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Factor 4A Eucariótico de Iniciación/metabolismo , ARN Helicasas DEAD-box/metabolismoRESUMEN
BACKGROUND: The molecular mechanism of the significant role of long noncoding RNAs (lncRNAs) in the progression and metastasis of gastric cancer (GC) remains largely elusive. Our objective is to detect overexpressed lncRNA in GC and investigate its role in promoting epithelial-mesenchymal transition and tumour microenvironment remodel. METHODS: LncRNA differential expression profile in GC was analysed using RNA microarrays. The level of LINC00501 was evaluated in both GC patient tissues and GC cell lines by quantitative reverse transcription PCR and large-scale (n = 304) tissue microarray. To explore the biological role and regulatory driver of LINC00501 in GC, various experimental techniques including Chromatin isolation by RNA purification (ChIRP), RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP) assay, dual luciferase assays were performed. RESULTS: Clinically, it was observed that LINC00501 level was abnormal overexpression in GC tissue and was associated with GC progression and distant metastasis. Gain and loss molecular biological experiments suggested that LINC00501, promoted EMT process and angiogenesis of GC. Mechanically, the enrichment of H3K27 acetylation in LINC00501 promoter region contributed to the increase of LINC00501 in GC. LINC00501 transactivated transcription of SLUG, by recruiting hnRNPR to its promoter. The growth of GC was inhibited both in vitro and in vivo by suppressing the level of LINC00501 using pharmacological intervention from the histone acetyltransferase (HAT) inhibitor -C646. CONCLUSIONS: This study suggests that LINC00501 promotes GC progression via hnRNPR/SLUG pathway, which indicates a promising biomarker and target for GC.
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ARN Largo no Codificante , Neoplasias Gástricas , Humanos , Regulación hacia Arriba/genética , Neoplasias Gástricas/patología , Transición Epitelial-Mesenquimal/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Acetilación , Microambiente TumoralRESUMEN
OBJECTIVE: To observe the effects of the Xingnao Kaiqiao (regaining consciousness and opening orifices) acupuncture on hemorrhagic transformation and limb motor function after intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) in stroke patients. METHODS: A total of 130 stroke patients after rt-PA thrombolytic were divided into an acupuncture group (58 cases, 1 case dropped off) and a non-acupuncture group (72 cases, 7 cases dropped off) according to whether they received acupuncture treatment. Propensity score matching (PSM) was used to match each group, with 38 patients in each group. The patients in the non-acupuncture group received rt-PA thrombolytic therapy and western medical basic treatment. In addition to the basic treatment, the patients in the acupuncture group received Xingnao Kaiqiao acupuncture at Shuigou (GV 26), bilateral Neiguan (PC 6), and ipsilateral Sanyinjiao (SP 6), Chize (LU 5), once a day for 14 days. The incidence of hemorrhagic transformation within 30 days after onset was compared between the two groups. The Fugl-Meyer assessment (FMA) score and activities of daily living (ADL) score were observed at baseline and 30 days, 6 months, 1 year after onset in the two groups. The disability rate at 6 months and 1 year after onset was recorded, and safety was evaluated in both groups. RESULTS: The incidence of hemorrhagic transformation in the acupuncture group was 5.3% (2/38), which was lower than 21.1% (8/38) in the non-acupuncture group (P<0.05). At 30 days, 6 month, and 1 year after onset, the FMA and ADL scores of both groups were higher than those at baseline (P<0.01), and the scores in the acupuncture group were higher than those in the non-acupuncture group (P<0.01). The disability rate in the acupuncture group at 1 year after onset was 10.5% (4/38), which was lower than 28.9% (11/38) in the non-acupuncture group (P<0.05). There was no significant difference in the incidence of adverse events between the two groups (P>0.05). CONCLUSION: The Xingnao Kaiqiao acupuncture method could reduce the incidence of hemorrhagic transformation in stroke patients after intravenous thrombolysis with rt-PA, improve their motor function and daily living ability, and reduce the long-term disability rate.
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Terapia por Acupuntura , Accidente Cerebrovascular , Humanos , Activador de Tejido Plasminógeno/efectos adversos , Actividades Cotidianas , Estudios Prospectivos , Terapia Trombolítica/efectos adversosRESUMEN
Pulmonary fibrosis (PF) is an interstitial lung disease characterized by the destruction of the pulmonary parenchyma caused by excessive extracellular matrix deposition. Despite the well-known etiological factors such as senescence, aberrant epithelial cell and fibroblast activation, and chronic inflammation, PF has recently been recognized as a metabolic disease and abnormal lipid signature was observed both in serum and bronchoalveolar lavage fluid (BALF) of PF patients and mice PF model. Clinically, observational studies suggest a significant link between high-fat diet (HFD) and PF as manifested by high intake of saturated fatty acids (SFAs) and meat increases the risk of PF and mice lung fibrosis. However, the possible mechanisms between HFD and PF remain unclear. In the current review we emphasize the diversity effects of the epigenetic dysregulation induced by HFD on the fibrotic factors such as epithelial cell injury, abnormal fibroblast activation and chronic inflammation. Finally, we discuss the potential ways for patients to improve their conditions and emphasize the prospect of targeted therapy based on epigenetic regulation for scientific researchers or drug developers.
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Fibrosis Pulmonar , Animales , Ratones , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/inducido químicamente , Dieta Alta en Grasa/efectos adversos , Epigénesis Genética , Pulmón/metabolismo , Inflamación/metabolismoRESUMEN
Immune checkpoint blockade (ICB) therapy targeting PD-1/PD-L1 has shown durable clinical benefits in lung cancer. However, many patients respond poorly to ICB treatment, underscoring an incomplete understanding of PD-L1 regulation and therapy resistance. Here, we find that MTSS1 is downregulated in lung adenocarcinoma, leading to PD-L1 upregulation, impairment of CD8+ lymphocyte function, and enhanced tumor progression. MTSS1 downregulation correlates with improved ICB efficacy in patients. Mechanistically, MTSS1 interacts with the E3 ligase AIP4 for PD-L1 monoubiquitination at Lysine 263, leading to PD-L1 endocytic sorting and lysosomal degradation. In addition, EGFR-KRAS signaling in lung adenocarcinoma suppresses MTSS1 and upregulates PD-L1. More importantly, combining AIP4-targeting via the clinical antidepressant drug clomipramine and ICB treatment improves therapy response and effectively suppresses the growth of ICB-resistant tumors in immunocompetent mice and humanized mice. Overall, our study discovers an MTSS1-AIP4 axis for PD-L1 monoubiquitination and reveals a potential combinatory therapy with antidepressants and ICB.
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The International Society of RNA Nanotechnology and Nanomedicine (ISRNN) serves to further the development of a wide variety of functional nucleic acids and other related nanotechnology platforms. To aid in the dissemination of the most recent advancements, a biennial discussion focused on biomotors, viral assembly, and RNA nanobiotechnology has been established where international experts in interdisciplinary fields such as structural biology, biophysical chemistry, nanotechnology, cell and cancer biology, and pharmacology share their latest accomplishments and future perspectives. The results summarized here highlight advancements in our understanding of viral biology and the structure-function relationship of frame-shifting elements in genomic viral RNA, improvements in the predictions of SHAPE analysis of 3D RNA structures, and the understanding of dynamic RNA structures through a variety of experimental and computational means. Additionally, recent advances in the drug delivery, vaccine design, nanopore technologies, biomotor and biomachine development, DNA packaging, RNA nanotechnology, and drug delivery are included in this critical review. We emphasize some of the novel accomplishments, major discussion topics, and present current challenges and perspectives of these emerging fields.
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Inducible degrader of low-density lipoprotein (LDL) receptor (Idol) is an E3 ubiquitin ligase coded by Idol, the target gene of liver X receptor (LXR), which primarily mediates the ubiquitination and lysosomal degradation of low-density lipoprotein receptor (LDLR). Previous studies from independent groups have shown that plasma cholesterol regulation by the LXR-Idol-LDLR axis is tissue- and species-specific, indicating that the precise molecular mechanism by which Idol modulates lipid metabolism has not been completely understood and needs to be further validated in other species. Hamster, a small rodent animal model expressing endogenous cholesterol ester transfer protein (CETP), possesses many metabolic characteristics that are different from mouse but similar to human. In this study, an Idol knockout (Idol-/-) hamster model was developed using CRISPR/Cas9 gene editing system to investigate the effect of Idol depletion on plasma lipid metabolism and atherosclerosis. Our results showed that there were no significant differences in hepatic LDLR protein and plasma cholesterol levels in Idol-/- hamsters compared with wild-type (WT) controls, which was consistent with the observation that LXR agonist treatment increased the expression of Idol mRNA in the small intestine but not in the liver of WT hamsters. However, we found that plasma triglyceride (TG) levels were significantly reduced in Idol-/- hamsters due to an enhancement of TG clearance. In addition, the morphological data demonstrated that inactivation of Idol significantly lowered plasma total cholesterol and TG levels and protected against spontaneous atherosclerotic lesions in aged LDLR knockout hamsters on a chow diet but had no effect on diet-induced atherosclerosis in hamsters lacking one copy of the Ldlr gene. In conclusion, our findings suggest that Idol can regulate plasma lipid metabolism and atherosclerosis independent of LDLR function.
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Aterosclerosis , Hiperlipoproteinemia Tipo II , Animales , Colesterol , Cricetinae , Modelos Animales de Enfermedad , Lipoproteínas LDL , Receptores X del Hígado , RatonesRESUMEN
Vascular smooth muscle cell (VSMC) subpopulations relevant to vascular disease and injury repair have been depicted in healthy vessels and atherosclerosis profiles. However, whether VSMC subpopulation associated with vascular homeostasis exists in the healthy artery and how are their nature and fate in vascular remodeling remains elusive. Here, using single-cell RNA-sequencing (scRNA-seq) to detect VSMC functional heterogeneity in an unbiased manner, we showed that VSMC subpopulations in healthy artery presented transcriptome diversity and that there was significant heterogeneity in differentiation state and development within each subpopulation. Notably, we detected an independent subpopulation of VSMCs that highly expressed regulator of G protein signaling 5 (RGS5), upregulated the genes associated with inhibition of cell proliferation and construction of cytoskeleton compared with the general subpopulation, and mainly enriched in descending aorta. Additionally, the proportion of RGS5high VSMCs was markedly decreased or almost disappeared in the vascular tissues of neointimal formation, abdominal aortic aneurysm and atherosclerosis. Specific spatiotemporal characterization of RGS5high VSMC subpopulation suggested that this subpopulation was implicated in vascular homeostasis. Together, our analyses identify homeostasis-relevant transcriptional signatures of VSMC subpopulations in healthy artery, which may explain the regional vascular resistance to atherosclerosis at some extent.
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Aterosclerosis , Músculo Liso Vascular , Proteínas RGS/metabolismo , Aterosclerosis/metabolismo , Proliferación Celular , Células Cultivadas , Proteínas de Unión al GTP/metabolismo , Humanos , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Neointima/metabolismoRESUMEN
Nanomotors in nanotechnology may be as important as cars in daily life. Biomotors are nanoscale machines ubiquitous in living systems to carry out ATP-driven activities such as walking, breathing, blinking, mitosis, replication, transcription, and trafficking. The sequential action in an asymmetrical hexamer by a revolving mechanism has been confirmed in dsDNA packaging motors of phi29, herpesviruses, bacterial dsDNA translocase FtsK, and Streptomyces TraB for conjugative dsDNA transfer. These elaborate, delicate, and exquisite ring structures have inspired scientists to design biomimetics in nanotechnology. Many multisubunit ATPase rings generate force via sequential action of multiple modules, such as the Walker A, Walker B, P-loop, arginine finger, sensors, and lid. The chemical to mechanical energy conversion usually takes place in sequential order. It is commonly believed that ATP binding triggers such conversion, but how the multimodule motor starts the sequential process has not been explicitly investigated. Identification of the starter is of great significance for biomimetic motor fabrication. Here, we report that the arginine finger is the starter of the motor. Only one amino acid residue change in the arginine finger led to the impediment and elimination of all following steps. Without the arginine finger, the motor failed to assemble, bind ATP, recruit DNA, or hydrolyze ATP and was eventually unable to package DNA. However, the loss of ATPase activity due to an inactive arginine finger can be rescued by an arginine finger from the adjacent subunit of Walker A mutant through trans-complementation. Taken together, we demonstrate that the formation of dimers triggered by the arginine finger initiates the motor action rather than the general belief of initiation by ATP binding.
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Biomimética , Empaquetamiento del ADN , Arginina , ADN Viral , Adenosina Trifosfatasas/química , Adenosina Trifosfato/metabolismo , Ensamble de VirusRESUMEN
Lung metastasis is the major cause of breast cancer-related mortality. The neutrophil-associated inflammatory microenvironment aids tumor cells in metastatic colonization in lungs. Here, we show that tumor-secreted protease cathepsin C (CTSC) promotes breast-to-lung metastasis by regulating recruitment of neutrophils and formation of neutrophil extracellular traps (NETs). CTSC enzymatically activates neutrophil membrane-bound proteinase 3 (PR3) to facilitate interleukin-1ß (IL-1ß) processing and nuclear factor κB activation, thus upregulating IL-6 and CCL3 for neutrophil recruitment. In addition, the CTSC-PR3-IL-1ß axis induces neutrophil reactive oxygen species production and formation of NETs, which degrade thrombospondin-1 and support metastatic growth of cancer cells in the lungs. CTSC expression and secretion are associated with NET formation and lung metastasis in human breast tumors. Importantly, targeting CTSC with compound AZD7986 effectively suppresses lung metastasis of breast cancer in a mouse model. Overall, our findings reveal a mechanism of how tumor cells regulate neutrophils in metastatic niches and support CTSC-targeting approaches for cancer treatment.
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Neoplasias de la Mama/metabolismo , Catepsina C/metabolismo , Trampas Extracelulares/metabolismo , Neoplasias Pulmonares/metabolismo , Infiltración Neutrófila/fisiología , Neutrófilos/metabolismo , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Humanos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neutrófilos/patología , Especies Reactivas de Oxígeno/metabolismo , Microambiente Tumoral/fisiologíaRESUMEN
BACKGROUND: Obesity is a fundamental factor in metabolic disorders such as hyperlipidemia, insulin resistance, fatty liver, and atherosclerosis. However, effective preventive measures are still lacking. This study aimed to investigate different surgical protocols for removing partial adipose tissue before the onset of obesity and determine whether, and by which protocol, preliminary adipose removal could exert potent preventive effects against diet-induced metabolic disorders. METHODS: Male low-density lipoprotein receptor (LDL-R) knockout (KO) mice were randomly divided into four groups and subjected to epididymal fat removal (Epi-FR) surgery, subcutaneous fat removal (suQ-FR) surgery, both subcutaneous and epididymal fat removal (Epi + suQ-FR) surgery, or sham-operation. After 1 week of recovery, all mice were given a high-fat diet (HFD) for 10 weeks to induce metabolic disorders. RESULTS: In the Epi-FR group and the sham-operated group, the mean numbers of the residual subcutaneous fat were 28.59 mg/g and 18.56 mg/g, respectively. The expression of relative genes such as Pparg, Cebpa, Dgat2, Fabp4 and Cd36 in the residual subcutaneous fat increased 2.62, 3.90, 3.11, 2.06, 1.78 times in the Epi-FR group compared with that in the sham-operated group. Whereas in the other fat-removal groups, the residual fat depots had no significant change in either size or gene expression, as compared with those of the sham-operated group. Plasma lipid and glucose levels and insulin sensitivity, as detected by the glucose tolerance test, were not significantly alleviated in the three fat removal groups. Liver mass or lipid content was not attenuated in any of the three fat removal groups. The atherosclerosis burdens in the entire inner aorta and aortic root did not decrease in any of the three fat removal groups. CONCLUSIONS: Our data suggest that removal of epididymal adipose or subcutaneous adipose alone or in combination before the onset of obesity did not protect against hyperlipidemia, insulin resistance, fatty liver, or atherosclerosis in LDL-R KO mice fed with a HFD. Hence, adipose removal possibly does not represent a potential approach in preventing obesity-related metabolic disorders in the obesity-susceptible population.
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Tejido Adiposo , Resistencia a la Insulina , Animales , Dieta Alta en Grasa/efectos adversos , Hígado , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad , Grasa SubcutáneaRESUMEN
Many years of fundamental studies on viral genome packaging motors have led to fruitful applications. The double-stranded DNA (dsDNA) viruses package their genomes into preformed protein shells via nanomotors including several elegant and meticulous coaxial modules. The motor is geared by the hexameric RNA ring. An open washer displayed as hexametric string of phi29 motor ATPase has been reported. The open washer linked into a filament as a queue with left-handed chirality along the dsDNA chain. It was found that a free 5'- and 3'-dsDNA end is not required for one gp16 dimer and four monomers to assemble into the hexametric washer on dsDNA. The above studies have inspired several applications in nanotechnology and nanomedicine. These applications include: (i) studies on the precision motor channels have led to their application in the single pore sensing; (ii) investigations into the hand-in-hand integration of the hexametric pRNA ring have resulted in the emergence of the new field of RNA nanotechnology; and (iii) the studies on the motor stoichiometry of homologous multi-subunits that subsequently have inspired the discovery of new methods in highly potent drug development. This review focuses on the structure and function of the viral DNA packaging motors and describes how fundamental studies inspired various applications. Given these advantages, more nanotechnological and biomedical applications using bacteriophage motor components are expected.
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Adenosina Trifosfatasas/metabolismo , Empaquetamiento del ADN , ADN Viral/metabolismo , Nanoporos , Ensamble de Virus , Secuencia de Bases , Genoma Viral , Conformación Molecular , Nanomedicina , Nanotecnología , ARN Viral/metabolismo , Transducción de Señal , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
This study investigated Janus particles (JPs) composed of an azo polymer and a pyrene-containing polymer, focusing on preparation, formation mechanism, photoinduced deformation behavior, and fluorescent properties as well as tunable colors of the dispersions. A methacrylate-based copolymer containing pyrenyl groups (P(MMA-co-PyMA)) and two azo polymers, i.e., a methacrylate-based polymer (PCNAZO) and an epoxy-based polymer (CH-TZ-NT) both bearing push-pull-type azo chromophores, were synthesized for this purpose. Two types of Janus particles, P(MMA-co-PyMA)/PCNAZO JPs and P(MMA-co-PyMA)/CH-TZ-NT JPs, were fabricated through microphase separation of the components in the droplets dispersed in aqueous media, induced by the evaporation of the organic solvent. The process of JP formation was thoroughly investigated by exploiting the function of pyrene moieties as a molecular probe through measuring the fluorescence emission spectra at different times during the structure evolution. The photoluminescent (PL) intensity, excimer emission, and vibrational fine structure of the fluorescence spectra were observed to give information about phase separation and solidification occurred in the dispersed droplets. The observations were rationalized by analysis with ternary phase diagrams calculated on the basis of the Flory-Huggins theory. Upon irradiation with a linearly polarized laser beam at 488 nm, the azo polymer parts in the P(MMA-co-PyMA)/PCNAZO JPs were observed to be elongated along the electric vibration direction of the polarized light and transformed into particles with unique morphologies. The dispersions of JPs with different compositions of the two types of the polymers showed highly tunable color changes originating from both fluorescence of the pyrenyl fluorophores and light absorption of the azo chromophores.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Lipodystrophy is a severe adipose dysfunction that can be classified as congenital or acquired lipodystrophy, in term of the etiology. Previous knowledge about the metabolic disorders and cardiovascular consequences were mostly obtained from lipodystrophic mice with genetic defects. To completely rule out the genetic influence, we established a mouse model of acquired generalized lipodystrophy by surgical removal of multiple fat depots, including subcutaneous fat in the inguinal, visceral fat in the epididymis and brown fat in the scapula, in atherosclerosis-prone LDLR-/- mice which were fed with a high-fat diet (HFD). It was observed that fat removal increased diet-induced hyperlipidemia, especially hypercholesteremia, as early as 2 weeks after HFD and till the end of HFD feeding. After 12 weeks on the HFD, the residual fats of fat-removed mice were found expanded. Although fat removal aggravated diet-induced lipid deposition in the liver and systemic insulin resistance, there was no significant difference in atherogenesis in fat-removed mice compared with sham-operated control mice. Acquired generalized lipodystrophy by surgical fat removal promoted metabolic disorders but not atherogenesis in LDLR-/- mice fed on HFD.