RESUMO
High cholesterol is a major risk factor for cardiovascular disease1. Currently, no drug lowers cholesterol through directly promoting cholesterol excretion. Human genetic studies have identified that the loss-of-function Asialoglycoprotein receptor 1 (ASGR1) variants associate with low cholesterol and a reduced risk of cardiovascular disease2. ASGR1 is exclusively expressed in liver and mediates internalization and lysosomal degradation of blood asialoglycoproteins3. The mechanism by which ASGR1 affects cholesterol metabolism is unknown. Here, we find that Asgr1 deficiency decreases lipid levels in serum and liver by stabilizing LXRα. LXRα upregulates ABCA1 and ABCG5/G8, which promotes cholesterol transport to high-density lipoprotein and excretion to bile and faeces4, respectively. ASGR1 deficiency blocks endocytosis and lysosomal degradation of glycoproteins, reduces amino-acid levels in lysosomes, and thereby inhibits mTORC1 and activates AMPK. On one hand, AMPK increases LXRα by decreasing its ubiquitin ligases BRCA1/BARD1. On the other hand, AMPK suppresses SREBP1 that controls lipogenesis. Anti-ASGR1 neutralizing antibody lowers lipid levels by increasing cholesterol excretion, and shows synergistic beneficial effects with atorvastatin or ezetimibe, two widely used hypocholesterolaemic drugs. In summary, this study demonstrates that targeting ASGR1 upregulates LXRα, ABCA1 and ABCG5/G8, inhibits SREBP1 and lipogenesis, and therefore promotes cholesterol excretion and decreases lipid levels.
Assuntos
Receptor de Asialoglicoproteína , Colesterol , Metabolismo dos Lipídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Membro 5 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Membro 8 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Receptor de Asialoglicoproteína/antagonistas & inibidores , Receptor de Asialoglicoproteína/deficiência , Receptor de Asialoglicoproteína/genética , Receptor de Asialoglicoproteína/metabolismo , Assialoglicoproteínas/metabolismo , Atorvastatina/farmacologia , Proteína BRCA1 , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Colesterol/metabolismo , Sinergismo Farmacológico , Endocitose , Ezetimiba/farmacologia , Humanos , Lipídeos/análise , Lipídeos/sangue , Fígado/metabolismo , Receptores X do Fígado/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Proteína de Ligação a Elemento Regulador de Esterol 1 , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Hedgehog (Hh) signaling pathway plays a pivotal role in embryonic development. Hh binding to Patched1 (PTCH1) derepresses Smoothened (SMO), thereby activating the downstream signal transduction. Covalent SMO modification by cholesterol in its cysteine-rich domain (CRD) is essential for SMO function. SMO cholesterylation is a calcium-accelerated autoprocessing reaction, and STIM1-ORAI1-mediated store-operated calcium entry promotes cholesterylation and activation of endosome-localized SMO. However, it is unknown whether the Hh-PTCH1 interplay regulates the activity of the endoplasmic reticulum (ER)-localized SMO. Here, we found that PTCH1 inhibited the COPII-dependent export of SMO from the ER, whereas Hh promoted this process. The RRxWxR amino acid motif in the cytosolic tail of SMO was essential for COPII recognition, ciliary localization, and signal transduction activity. Hh and PTCH1 regulated cholesterol modification of the ER-localized SMO, and SMO cholesterylation accelerated its exit from ER. The GRAMD1/ASTER sterol transport proteins facilitated cholesterol transfer to ER from PM, resulting in increased SMO cholesterylation and enhanced Hh signaling. Collectively, we reveal a regulatory role of GRAMD-mediated cholesterol transport in ER-resident SMO maturation and Hh signaling.
Assuntos
Cálcio , Proteínas Hedgehog , Transporte Biológico , Cálcio/metabolismo , Colesterol/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/fisiologia , Receptor Smoothened/genética , Receptor Smoothened/metabolismo , Proteínas de Membrana/metabolismoRESUMO
Cholesterol is an essential lipid and its synthesis is nutritionally and energetically costly1,2. In mammals, cholesterol biosynthesis increases after feeding and is inhibited under fasting conditions3. However, the regulatory mechanisms of cholesterol biosynthesis at the fasting-feeding transition remain poorly understood. Here we show that the deubiquitylase ubiquitin-specific peptidase 20 (USP20) stabilizes HMG-CoA reductase (HMGCR), the rate-limiting enzyme in the cholesterol biosynthetic pathway, in the feeding state. The post-prandial increase in insulin and glucose concentration stimulates mTORC1 to phosphorylate USP20 at S132 and S134; USP20 is recruited to the HMGCR complex and antagonizes its degradation. The feeding-induced stabilization of HMGCR is abolished in mice with liver-specific Usp20 deletion and in USP20(S132A/S134A) knock-in mice. Genetic deletion or pharmacological inhibition of USP20 markedly decreases diet-induced body weight gain, reduces lipid levels in the serum and liver, improves insulin sensitivity and increases energy expenditure. These metabolic changes are reversed by expression of the constitutively stable HMGCR(K248R). This study reveals an unexpected regulatory axis from mTORC1 to HMGCR via USP20 phosphorylation and suggests that inhibitors of USP20 could be used to lower cholesterol levels to treat metabolic diseases including hyperlipidaemia, liver steatosis, obesity and diabetes.
Assuntos
Colesterol/biossíntese , Ingestão de Alimentos/fisiologia , Hidroximetilglutaril-CoA Redutases/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Ubiquitina Tiolesterase/metabolismo , Animais , Linhagem Celular , Glucose/metabolismo , Humanos , Insulina/metabolismo , Fígado/metabolismo , Masculino , Doenças Metabólicas/genética , Doenças Metabólicas/metabolismo , Metabolismo/genética , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Fosfosserina/metabolismo , Ubiquitina Tiolesterase/antagonistas & inibidores , Ubiquitina Tiolesterase/química , Ubiquitina Tiolesterase/deficiência , Ubiquitinação , Aumento de PesoRESUMO
Sterol-regulatory element binding proteins (SREBPs) are a conserved transcription factor family governing lipid metabolism. When cellular cholesterol level is low, SREBP2 is transported from the endoplasmic reticulum to the Golgi apparatus where it undergoes proteolytic activation to generate a soluble N-terminal fragment, which drives the expression of lipid biosynthetic genes. Malfunctional SREBP activation is associated with various metabolic abnormalities. In this study, we find that overexpression of the active nuclear form SREBP2 (nSREBP2) causes caspase-dependent lytic cell death in various types of cells. These cells display typical pyroptotic and necrotic signatures, including plasma membrane ballooning and release of cellular contents. However, this phenotype is independent of the gasdermin family proteins or mixed lineage kinase domain-like (MLKL). Transcriptomic analysis identifies that nSREBP2 induces expression of p73, which further activates caspases. Through whole-genome CRISPR-Cas9 screening, we find that Pannexin-1 (PANX1) acts downstream of caspases to promote membrane rupture. Caspase-3 or 7 cleaves PANX1 at the C-terminal tail and increases permeability. Inhibition of the pore-forming activity of PANX1 alleviates lytic cell death. PANX1 can mediate gasdermins and MLKL-independent cell lysis during TNF-induced or chemotherapeutic reagents (doxorubicin or cisplatin)-induced cell death. Together, this study uncovers a noncanonical function of SREBPs as a potentiator of programmed cell death and suggests that PANX1 can directly promote lytic cell death independent of gasdermins and MLKL.
Assuntos
Morte Celular , Conexinas , Proteínas do Tecido Nervoso , Proteína de Ligação a Elemento Regulador de Esterol 2 , Humanos , Caspase 3/metabolismo , Caspase 7/metabolismo , Morte Celular/efeitos dos fármacos , Conexinas/metabolismo , Conexinas/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismoRESUMO
The clinical treatment of hepatocellular carcinoma (HCC) is still a heavy burden worldwide. Intracellular microRNAs (miRNAs) commonly express abnormally in cancers, thus they are potential therapeutic targets for cancer treatment. miR-21 is upregulated in HCC whereas miR-122 is enriched in normal hepatocyte but downregulated in HCC. In our study, we first generated a reporter genetic switch compromising of miR-21 and miR-122 sponges as sensor, green fluorescent protein (GFP) as reporter gene and L7Ae:K-turn as regulatory element. The reporter expression was turned up in miR-21 enriched environment while turned down in miR-122 enriched environment, indicating that the reporter switch is able to respond distinctly to different miRNA environment. Furthermore, an AAT promoter, which is hepatocyte-specific, is applied to increase the specificity to hepatocyte. A killing switch with AAT promoter and an apoptosis-inducing element, Bax, in addition to miR-21 and miR-122 significantly inhibited cell viability in Huh-7 by 70 % and in HepG2 by 60 %. By contrast, cell viability was not affected in five non-HCC cells. Thus, we provide a novel feasible strategy to improve the safety of miRNA-based therapeutic agent to cancer.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Regiões Promotoras Genéticas , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Regiões Promotoras Genéticas/genética , Genes Reporter , Células Hep G2 , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genética , Especificidade de Órgãos/genéticaRESUMO
Thiols and thioesters play crucial roles in pharmaceuticals, biology, and material science as essential organosulfur compounds. Leveraging readily available and cost-effective inert alkanes through direct thioetherification holds promise for yielding high-value-added products. Herein, we present a photoinduced strategy for sulfur-containing modification of inert alkanes utilizing decatungstate as hydrogen atom transfer reagent, offering a straightforward and practical approach for synthesizing thioethers and thioesters.
RESUMO
Catalytic C(sp3)-H functionalization has provided enormous opportunities to construct organic molecules, facilitating the derivatization of complex pharmaceutical compounds. Within this framework, direct hydrogen atom transfer (HAT) photocatalysis becomes an appealing approach to this goal. However, the viable substrates utilized in these protocols are limited, and the site selectivity shows preference to activated and thermodynamically favored C(sp3)-H bonds. Herein, we describe the development of undirected iron-catalyzed C(sp3)-H borylation, thiolation, and sulfinylation reactions enabled by the photoinduced ligand-to-metal charge transfer (LMCT) process. These reactions exhibit remarkably broad substrate scope (>150 examples in total), and most importantly, all of these three reactions show unconventional regioselectivity, with the occurrence of C(sp3)-H borylation, thiolation, and sulfinylation preferentially at the distal methyl position. The procedures are operationally simple and readily scalable and provide access to high-value products from simple hydrocarbons in one step. Mechanistic studies and control experiments indicate that the afforded site selectivity is not only relevant to the HAT species but also largely affected by the use of boron- and sulfone-based radical acceptors.
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Laser-induced breakdown spectroscopy (LIBS) plays an increasingly important role in the classification and recycling of aluminum alloys owing to its outstanding elemental analysis performance. For LIBS measurements with sample surface fluctuations, consistently and exactly maintaining the laser and fiber focus points on the sample surface is difficult, and fluctuations in the focus severely affect the stability of the spectrum. In this study, a data transfer method is introduced to reduce the effect of spectral fluctuations on the model performance. During the experiment, a focal point is placed on the sample surface. Then, keeping experimental conditions unchanged, the three-dimensional platform is only moved up and down along the z-axis by 0.5 mm, 1 mm, 1.5 mm, 2 mm and 2.5 mm, respectively. Eleven spectral datasets at different heights are collected for analysis. The KNN model is used as the base classifier, and the accuracies of the 11 datasets, from the lowest to the highest, are 11.48%, 19.71%, 30.57%, 45.71%, 53.57%, 88.28%, 52.57%, 21.42%, 14.42%, 14.42%, and 14.42%. To improve predictive performance, the difference in data distribution between the spectra collected at the sample surface and those collected at other heights is reduced by data transfer. Feature selection is introduced and combined with data transfer, and the final accuracies are 78.14%, 82.28%, 80.14%, 89.71%, 91.85%, 98.42%, 94.28%, 92.42%, 82.14%, 78.57%, and 73.71%. It can be seen that the proposed method provides a new feasible and effective way for the classification of aluminum alloys in a real detection environment.
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This study explored the medication rules of Chinese herbal compound prescriptions for the treatment of angina based on the Chinese herbal compound patents in the patent database of the China National Intellectual Property Administration. The data of eligible Chinese herbal compound patents for the treatment of angina were collected from the patent database of the China National Intellectual Property Administration from database inception to November 10, 2022, and subjected to data modeling, analysis of main syndromes, medication frequency analysis, cluster analysis, association rule analysis, and data visualization by using Excel 2021, IBM SPSS Statistics 26.0, IBM SPSS Modeler 18.0, Cytoscape 3.9.1, and Rstudio R 4.2.2.2 to explore the medication rules for angina. The study included 636 pieces of patent data for angina that met the inclusion criteria, involving 815 drugs, with a total frequency of 6 586. The most common main syndromes were blood stasis obstructing the heart syndrome(222, 34.91%) and Qi deficiency and blood stasis syndrome(112, 17.61%). The top 10 most frequently used drugs were Salviae Miltiorrhizae Radix et Rhizoma, Chuanxiong Rhizoma, Notoginseng Radix et Rhizoma, Astragali Radix, Angelicae Sinensis Radix, Carthami Flos, Glycyrrhizae Radix et Rhizoma, Ginseng Radix et Rhizoma, Borneolum Syntheticum, and Corydalis Rhizoma. High-frequency drugs included blood-activating and stasis-resolving drugs(1 197, 18.17%) and deficiency-tonifying drugs(809, 12.28%). Cluster analysis identified eight drug combinations, including five new prescriptions suitable for clinical use and new drug development, and three drug pairs. The core drug combination of Salviae Miltiorrhizae Radix et Rhizoma-Chuanxiong Rhizoma-Carthami Flos was identified through the complex co-occurrence network analysis of Chinese medicines. Association rule analysis yielded a total of 17 rules, including 13 drug pairs and 4 tripartite combinations. Common drug pairs included Salviae Miltiorrhizae Radix et Rhizoma-Chuanxiong Rhizoma(support degree 25.79%, confidence coefficient 69.49%, lift 1.30) and Salviae Miltiorrhizae Radix et Rhizoma-Notoginseng Radix et Rhizoma(support degree 22.01%, confidence coefficient 61.95%, lift 1.16). Common tripartite combinations included Salviae Miltiorrhizae Radix et Rhizoma-Chuanxiong Rhizoma-Astragali Radix(support degree 10.85%, confidence coefficient 73.40%, lift 1.37) and Salviae Miltiorrhizae Radix et Rhizoma-Chuanxiong Rhizoma-Notoginseng Radix et Rhizoma(support degree 10.69%, confidence coefficient 79.07%, lift 1.48). The results showed that the underlying pathogenesis of angina involved blood stasis obstructing the heart and Qi deficiency and blood stasis. The overall nature of the disease was characterized as asthenia in origin and sthenia in superficiality. In the prescription formulation, blood-activating and stasis-resolving drugs, such as Salviae Miltiorrhizae Radix et Rhizoma, Chuanxiong Rhizoma, and Carthami Flos were often used to resolve the excess manifestation, which were combined with tonifying drugs such as Astragali Radix, Angelicae Sinensis Radix, Glycyrrhizae Radix et Rhizoma, and Ginseng Radix et Rhizoma to reinforce the deficiency. The syndrome, pathogenesis, disease nature, and medication were consistent with clinical practice. Additionally, the new compound prescriptions and drug combinations derived from the multiple data mining in this study could provide references and insights for the clinical diagnosis and treatment of angina and the development of new drugs.
Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Angina Pectoris/tratamento farmacológico , Prescrições , Mineração de Dados , Combinação de MedicamentosRESUMO
BACKGROUND: Small solitary lung cancer (≤2 cm) with extra-thoracic metastasis and no nodal metastasis or intra-thoracic metastasis is a rare situation in clinic. METHODS: Lung cancer patients with stage T1aN0M0 and T1aN0M1b from 2010 to 2015 were identified from the Surveillance, Epidemiology, and End Results database. The identified significant parameters were utilized to develop 2 nomogram to predict the extra-thoracic metastasis rates and the overall survival for the group of patients with stage T1aN0M1b. RESULTS: Small solitary lung cancers which occur in the males, younger patients, or locate in the main bronchus or left lung, or with histologic type as small cell lung cancer, or with undifferentiated type, tend to have extra-thoracic metastasis. Application of the nomogram in the intra-group still gave good discrimination and good calibration. Univariable and multivariable analysis identified several clinical data as the prognostic factors for lung cancer patients with stage T1aN0M1b, all the factors above were incorporated into the nomogram. ROC curve analysis showed that the nomogram had good discrimination, with AUC of .779, .786 and .77 for 1-, 3- and 5-year survival in the development group and validation group, respectively. Moreover, decision curve analysis has been implemented to evaluate and compare prediction and prognostic nomogram. CONCLUSIONS: Younger male patients whose lung cancer locates in main bronchus or left lung, or with undifferentiated type, or with histologic type as small cell lung cancer are more likely to have extra-thoracic metastasis. The proposed nomogram reliably predicted OS for lung cancer patients with stage T1aN0M1b, though further validation is needed, it may be a useful tool in clinical practice. These models can be wildly used for easy facilitate the lung cancer individualized prediction of extra-thoracic metastasis and OS.
Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Masculino , Nomogramas , Carcinoma de Pequenas Células do Pulmão/epidemiologia , Carcinoma de Pequenas Células do Pulmão/patologia , Incidência , Estadiamento de Neoplasias , Neoplasias Pulmonares/patologia , PrognósticoRESUMO
Simultaneous localization and mapping (SLAM) is the major solution for constructing or updating a map of an unknown environment while simultaneously keeping track of a mobile robot's location. Correlative Scan Matching (CSM) is a scan matching algorithm for obtaining the posterior distribution probability for the robot's pose in SLAM. This paper combines the non-linear optimization algorithm and CSM algorithm into an NLO-CSM (Non-linear Optimization CSM) algorithm for reducing the computation resources and the amount of computation while ensuring high calculation accuracy, and it presents an efficient hardware accelerator design of the NLO-CSM algorithm for the scan matching in 2D LiDAR SLAM. The proposed NLO-CSM hardware accelerator utilizes pipeline processing and module reusing techniques to achieve low hardware overhead, fast matching, and high energy efficiency. FPGA implementation results show that, at 100 MHz clock, the power consumption of the proposed hardware accelerator is as low as 0.79 W, while it performs a scan match at 8.98 ms and 7.15 mJ per frame. The proposed design outperforms the ARM-A9 dual-core CPU implementation with a 92.74% increase and 90.71% saving in computing speed and energy consumption, respectively. It has also achieved 80.3% LUTs, 84.13% FFs, and 20.83% DSPs saving, as well as an 8.17× increase in frame rate and 96.22% improvement in energy efficiency over a state-of-the-art hardware accelerator design in the literature. ASIC implementation in 65 nm can further reduce the computing time and energy consumption per scan to 5.94 ms and 0.06 mJ, respectively, which shows that the proposed NLO-CSM hardware accelerator design is suitable for resource-limited and energy-constrained mobile and micro robot applications.
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The digital transformation of the defence sector is not exempt from innovative requirements and challenges, with the lack of availability of reliable, unbiased and consistent data for training automatisms (machine learning algorithms, decision-making, what-if recreation of operational conditions, support the human understanding of the hybrid operational picture, personnel training/education, etc.) being one of the most relevant gaps. In the context of cyber defence, the state-of-the-art provides a plethora of data network collections that tend to lack presenting the information of all communication layers (physical to application). They are synthetically generated in scenarios far from the singularities of cyber defence operations. None of these data network collections took into consideration usage profiles and specific environments directly related to acquiring a cyber situational awareness, typically missing the relationship between incidents registered at the hardware/software level and their impact on the military mission assets and objectives, which consequently bypasses the entire chain of dependencies between strategic, operational, tactical and technical domains. In order to contribute to the mitigation of these gaps, this paper introduces CYSAS-S3, a novel dataset designed and created as a result of a joint research action that explores the principal needs for datasets by cyber defence centres, resulting in the generation of a collection of samples that correlate the impact of selected Advanced Persistent Threats (APT) with each phase of their cyber kill chain, regarding mission-level operations and goals.
Assuntos
Conscientização , Software , Algoritmos , Comunicação , Humanos , Aprendizado de MáquinaRESUMO
Gold nanoclusters (AuNCs) have shown promising applications in biotherapy owing to their ultrasmall size and unique molecular-like properties. In order to better guide the preparations and applications of AuNCs, dihydrolipoic acid-protected AuNCs (DHLA-AuNCs) and glutathione-protected AuNCs (GSH-AuNCs) were selected as models and the interactions between them and calf thymus DNA (ctDNA) were studied in detail. The results showed that there was a small difference in the binding mechanisms and forces between both AuNCs and ctDNA. The quenching mechanisms of both AuNCs to (ctDNA-HO) were completely different. The binding constants indicated that the binding strength between DHLA-AuNCs and ctDNA was greater than those of GSH-AuNCs. The conformation investigations showed that GSH-AuNCs had a greater impact on the conformation of ctDNA, and both AuNCs were more inclined to interact with the A-T base pairs of ctDNA. These results indicate that the surface ligand had a significant effect on the interactions between AuNCs and DNA and might also further affect the applications of AuNCs, and these results could guide the preparations of AuNCs. For DHLA-AuNCs, their good biocompatibility made them a potential candidate for application in imaging, drug treatment, sensing, and so on. The resulting base accumulation of ctDNA and weak interactions made GSH-AuNCs have great potential for application in gene therapy, which was consistent with the current reports on the applications of these two AuNCs. This work has pointed out the directions for the preparations and applications of AuNCs.
Assuntos
Nanopartículas Metálicas , Preparações Farmacêuticas , Glutationa , OuroRESUMO
OBJECTIVE: A high level of LDL-C (low-density lipoprotein cholesterol) is a major risk factor for cardiovascular disease. The E3 ubiquitin ligase named IDOL (inducible degrader of the LDLR [LDL receptor]; also known as MYLIP [myosin regulatory light chain interacting protein]) mediates degradation of LDLR through ubiquitinating its C-terminal tail. But the expression profile of IDOL differs greatly in the livers of mice and humans. Whether IDOL is able to regulate LDL-C levels in humans remains to be determined. Approach and Results: By using whole-exome sequencing, we identified a nonsynonymous variant rs149696224 in the IDOL gene that causes a G51S (Gly-to-Ser substitution at the amino acid site 51) from a Chinese Uygur family. Large cohort analysis revealed IDOL G51S carriers (+/G51S) displayed significantly higher LDL-C levels. Mechanistically, the G51S mutation stabilized IDOL protein by inhibiting its dimerization and preventing self-ubiquitination and subsequent proteasomal degradation. IDOL(G51S) exhibited a stronger ability to promote ubiquitination and degradation of LDLR. Adeno-associated virus-mediated expression of IDOL(G51S) in mouse liver decreased hepatic LDLR and increased serum levels of LDL-C, total cholesterol, and triglyceride. CONCLUSIONS: Our study demonstrates that IDOL(G51S) is a gain-of-function variant responsible for high LDL-C in both humans and mice. These results suggest that IDOL is a key player regulating cholesterol level in humans.
Assuntos
LDL-Colesterol/sangue , Regulação da Expressão Gênica , Hiperlipoproteinemias/genética , RNA/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Hiperlipoproteinemias/sangue , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Receptores de LDL/sangue , Ubiquitina-Proteína Ligases/biossíntese , Sequenciamento Completo do Genoma/métodosRESUMO
The transport of LDL-derived cholesterol from lysosomes to peroxisomes is facilitated by membrane contacts formed between the lysosomal protein synaptotagmin VII and the peroxisomal lipid phosphatidylinositol 4, 5-bisphosphate [PI(4,5)P2]. Here, we used RNA interference to search for regulators of PI(4,5)P2 and to study the effects of altered PI(4,5)P2 homeostasis on cholesterol transport. We found that knockdown of phosphatidylinositol 5-phosphate 4-kinase type-2 α (PIP4K2A) reduced peroxisomal PI(4,5)P2 levels, decreased lysosome-peroxisome membrane contacts, and increased accumulation of lysosomal cholesterol in human SV-589 fibroblasts. Forced expression of peroxisome-localized, kinase-active PIP4K2A in the knockdown cells reduced cholesterol accumulation, and in vitro addition of recombinant PIP4K2A restored membrane contacts. These results suggest that PIP4K2A plays a critical role in intracellular cholesterol transport by upregulating PI(4,5)P2 levels in the peroxisomal membrane. Further research into PIP4K2A activity may inform future therapeutic interventions for managing lysosomal storage disorders.
Assuntos
Colesterol/metabolismo , Homeostase , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transporte Biológico , Células Cultivadas , Células HEK293 , HumanosRESUMO
Magnetic nanoparticles (MNPs) are promising in tumor treatments due to their capacity for magnetic hyperthermia therapy (MHT), chemodynamic therapy (CDT), and immuno-related therapies, but still suffer from unsatisfactory tumor inhibition in the clinic. Insufficient hydrogen peroxide supply, glutathione-induced resistance, and high-density extracellular matrix (ECM) are the barriers. Herein, we hierarchically decorated MNPs with disulfide bonds (S-S), dendritic L-arginine (R), and glucose oxidase (GOx) to form a nanosystem (MNPs-SS-R-GOx). Its outer GOx layer not only enhanced the H2O2 supply to produce .OH by Fenton reaction, but also generated stronger oxidants (ONOO-) together with the interfaced R layer. The inner S-S layer consumed glutathione to interdict its reaction with oxidants, thus enhancing CDT effects. Importantly, the generated ONOO- tripled the MMP-9 expression to induce ECM degradation, enabling much deeper penetration of MNPs and benefiting CDT, MHT, and immunotherapy. Finally, the MNPs-SS-R-GOx demonstrated a remarkable 91.7% tumor inhibition in vivo. STATEMENT OF SIGNIFICANCE: Magnetic nanoparticles (MNPs) are a promising tumor therapeutic agent but with limited effectiveness. Our hierarchical MNP design features disulfide bonds (S-S), dendritic L-arginine (R), and glucose oxidase (GOx), which boosts H2O2 supply for ·OH generation in Fenton reactions, produces potent ONOO-, and enhances chemodynamic therapy via glutathione consumption. Moreover, the ONOO- facilitates the upregulation of matrix metalloprotein expression beneficial for extracellular matrix degradation, which in turn enhances the penetration of MNPs and benefits the antitumor CDT/MHT/immuno-related therapy. In vivo experiments have demonstrated an impressive 91.7% inhibition of tumor growth. This hierarchical design offers groundbreaking insights for further advancements in MNP-based tumor therapy. Its implications extend to a broader audience, encompassing those interested in material science, biology, oncology, and beyond.
Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Nanopartículas , Neoplasias , Humanos , Glucose Oxidase , Peróxido de Hidrogênio , Nanopartículas de Magnetita/uso terapêutico , Estresse Oxidativo , Arginina , Glutationa , Nanopartículas/uso terapêutico , Neoplasias/terapia , Oxidantes , Dissulfetos , Fenômenos Magnéticos , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
Herein, aryl decarboxylative allylation, thiolation, and bromination reactions via photoinduced ligand-to-copper charge transfer are described. Utilizing inexpensive copper metal, the transformations of various aryl carboxylic acids enable the rapid synthesis of the corresponding alkene, thioether, and aryl bromide derivatives under visible light irradiation, which offers significant synthetic value. The reaction conditions are mild and straightforward, exhibiting a broad substrate compatibility. Furthermore, this method can be applied for the late-stage modification of complex drug molecules.
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Pulmonary sarcomatoid carcinoma (PSC) represents a rare and highly aggressive variant of lung cancer, characterized by its recalcitrance to conventional therapeutic modalities and the attendant dismal prognosis it confers. Recent breakthroughs in immunotherapy have presented novel prospects for PSC patients; nevertheless, the utility of neoadjuvant/conversional immunotherapy in the context of PSC remains ambiguous. In this report, we present a middle-aged male presenting with Stage III PSC, notable for its high expression of the programmed death-ligand 1 (PD-L1), initially deemed as non-resectable for sizeable tumor mass and multiple lymph nodes metastases. The patient underwent a transformation to a resectable state after a regimen of three cycles of platinum-based chemotherapy plus immunotherapy. Following definitive surgical resection, the individual realized a pathological complete response (pCR), culminating in a significant prolongation of event-free survival (EFS). This case underscores the viability of employing immunochemotherapy as a neoadjuvant/conversional strategy for chosen cases of PSC.
Assuntos
Neoplasias Pulmonares , Humanos , Masculino , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Neoadjuvante/métodos , Imunoterapia/métodos , Resultado do Tratamento , Antígeno B7-H1/antagonistas & inibidores , Carcinossarcoma/terapia , Carcinossarcoma/patologia , Carcinossarcoma/tratamento farmacológicoRESUMO
Whole milk powder and skimmed milk powder are suitable for different groups of people due to their differences in composition. Therefore, a rapid classification method for whole milk powder and skimmed milk powder is urgently needed. In this paper, a novel strategy based on laser-induced breakdown spectroscopy (LIBS) and feature processing methods combined with logistic regression (LR) was constructed for the classification of milk powder. A LR classification model based on mini-batch gradient descent (MGD) was employed first. As indicated by the research results, the accuracy of the MGD-LR model for the milk powder samples in the test set is 96.33% and the modeling time is 33.07 s. The modeling efficiency is low and needs to be improved. Principal components analysis (PCA) and mutual information (MI) were used as feature processing methods to reduce the high dimensional LIBS data into fewer features for improving the modeling efficiency of the classification model. The research results indicate that the accuracy of the PCA-MGD-LR model and the MI-MGD-LR model for the test set of milk powder samples was 99.33% and 99.67%, respectively. Compared with MGD-LR model, the modeling efficiency of PCA-MGD-LR and MI-MGD-LR models has increased by 89.7% and 74.8%, respectively. The results fully demonstrate the feasibility of rapid milk powder classification based on LIBS and feature processing methods combined with LR, and it will provide a new technology for the identification and classification of milk powder.
Assuntos
Lasers , Leite , Humanos , Animais , Leite/química , Pós/análise , Modelos Logísticos , Análise Espectral/métodosRESUMO
Herein, we describe a novel photoinduced iron-catalyzed strategy for multicomponent C-H alkylation of in situ generated imines. By utilizing the alkyl radicals generated through iron-mediated photocatalytic C-H activation, the imines formed in situ are further subjected to addition reactions, resulting in the synthesis of various secondary and tertiary amine products. This method is simple to operate and does not require additional oxidants. It is applicable to inert alkane substrates such as cyclic alkanes, cyclic ethers, toluene, and ketones. The reaction is also compatible with various aromatic amines, alkyl amines, halogenated aromatic amines, as well as aromatic aldehydes, alkyl aldehydes, and cinnamaldehyde, among other different types of aldehydes.