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Extracellular vesicles (EVs) such as ectosomes and exosomes have gained attention as promising natural carriers for drug delivery. Exosomes, which range from 30 to 100 nm in diameter, possess a lipid bilayer and are secreted by various cells. Due to their high biocompatibility, stability, and low immunogenicity, exosomes are favored as cargo carriers. The lipid bilayer membrane of exosomes also offers protection against cargo degradation, making them a desirable candidate for drug delivery. However, loading cargo into exosomes remains to be a challenge. Despite various strategies such as incubation, electroporation, sonication, extrusion, freeze–thaw cycling, and transfection that have been developed to facilitate cargo loading, inadequate efficiency still persists. This review offers an overview of current cargo delivery strategies using exosomes and summarizes recent approaches for loading small-molecule, nucleic acid, and protein drugs into exosomes. With insights from these studies, we provide ideas for more efficient and effective delivery of drug molecules by using exosomes. [ABSTRACT FROM AUTHOR]

Dengue fever is the most common mosquito-borne viral disease and is caused by the dengue virus (DENV). There is still a lack of efficient drugs against DENV infection, so it is urgent to develop new inhibitors for future clinical use. Our previous research indicated the role of VEGFR2/AMPK in regulating cellular metabolism during DENV infection, while acetyl-CoA carboxylase (ACC) is located downstream of AMPK and plays a crucial role in mediating cellular lipid synthesis; therefore, we speculated that an ACC inhibitor could serve as an antiviral agent against DENV. Luckily, we found that CP640186, a reported noncompetitive ACC inhibitor, significantly inhibited DENV proliferation, and CP640186 clearly reduced DENV2 proliferation at an early stage with an EC50 of 0.50 μM. A mechanism study indicated that CP640186 inhibited ACC activation and destroyed the cellular lipid environment for viral proliferation. In the DENV2 infection mice model, oral CP640186 administration (10 mg/kg/day) significantly improved the mice survival rate after DENV2 infection. In summary, our research suggests that lipid synthesis plays an important role during DENV2 proliferation and indicates that CP640186 is a promising drug candidate against DNEV2 in the future. [ABSTRACT FROM AUTHOR]

Introduction: Pancreatic β-cell dysfunction is largely regulated by TXNIP accumulation, we have previously disclosed the role of PKA in TXNIP degradation during β-cell dysfunction. However, whether other kinases (PKCs) still regulate TXNIP is unclear, which is beneficial to alleviate β-cell dysfunction. Methods: Thapsigargin (ER stress inducer) was used to induce β-cell dysfunction. PKC's inhibitors were screened by Western blotting indicated by TXNIP. Also RT-qPCR and Co-immunoprecipitation were applied for evaluating the β-cell improvement ability of PKC's inhibitors, and the insulin secretion ability was evaluated by glucose-stimulated insulin secretion assay. Results: PKC's pan-inhibitor, Ro31-8220, decreased β-cell apoptosis and improved insulin secretion under ER stress or high glucose (HG) conditions. Further studies showed that Ro31-8220 reduced ER stress or HG-induced TXNIP levels. On the other side, PKCβ activation or overexpression could reverse the effect of Ro31-8220 on TXNIP. Also, PKCβ selective inhibitor, ruboxistaurin, induced TXNIP degradation as significantly as Ro31-8220 did. Conclusion: This study reveals the regulating mechanism of PKCβ inhibitor on TXNIP degradation to improve β-cell dysfunction. These data indicated PKCβ inhibitor is a promising agent for ameliorating β-cell dysfunction through TXNIP. [ABSTRACT FROM AUTHOR]

A novel formal (4 + 1) annulation between N -(o -chloromethyl)aryl amides and 3-chlorooxindoles through in situ generated aza- ortho -QMs with 3-chlorooxindoles is reported for the synthesis of a series of 2,3′-spirobi (indolin)-2′-ones in high yields. Under structured illumination microscopy, compound 3a is found to change the mitochondrial morphology and induce mitophagy pathway, which might then trigger mitophagy in cancer cells. [ABSTRACT FROM AUTHOR]

We reported here a cobalt‐catalyzed [5+1] annulation with 1,5‐diarylpenta‐1,4‐dien‐3‐ones and 2‐methylquinolines. 3,4,5‐Triarylcyclohexanones were furnished in moderate to good yields and excellent diastereoselectivity under simple reaction conditions. Moreover, we preliminarily studied anticancer activities of the obtained products in vitro by MTT {3‐(4,5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide} assay. [ABSTRACT FROM AUTHOR]

Transient delivery of CRISPR‐based genome editing effectors is important to reduce off‐target effects and immune responses. Recently extracellular vesicles (EVs) have been explored for Cas9 ribonucleoprotein (RNP) delivery. However, lack of mechanisms to enrich RNPs into EVs limited the efficiency of EVs as a RNP delivery vehicle. Here we describe a mechanism to actively enrich RNPs into EVs. We used the specific interaction between RNA aptamer and aptamer‐binding protein (ABP) to enrich RNPs into EVs. We inserted RNA aptamer com into single guide RNA (sgRNA), and fused com‐binding ABP Com to both termini of tetraspan protein CD63 that is abundant in exosomes. We found that the Com/com interaction enriched Cas9 and adenine base editor (ABE) RNPs into EVs, via forming a three‐component complex including CD63‐Com fusion protein, com‐modified sgRNA and Cas9 or ABE. The RNP enriched EVs are efficient in genome editing and transiently expressed. The system is capable of delivering RNPs targeting multiple loci for multiplex genome editing. In addition, Cas9 from different species can be used together. The EV‐delivered RNPs are active in vivo. The data show that the aptamer and ABP interactions can be utilized to actively enrich RNPs into EVs for improved genome editing efficiency and safety. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum stress (ER stress) plays a main role in pancreatic β -cell dysfunction and death because of intracellular Ca 2 + turbulence and inflammation activation. Although several drugs are targeting pancreatic β -cell to improve β -cell function, there still lacks agents to alleviate β -cell ER stress conditions. Therefore we used thapsigargin (THAP) or high glucose (HG) to induce ER stress in β -cell and aimed to screen natural molecules against ER stress-induced β -cell dysfunction. Through screening the Traditional Chinese drug library (∼ 1 0 0 0 molecules), luteolin was finally discovered to improve β -cell function. Cellular viability results indicated luteolin reduced the THAP or HG-induced β -cell death and apoptosis through MTT and flow cytometry assay. Moreover, luteolin improved β -cell insulin secretion ability under ER stress conditions. Also ER stress-induced intracellular Ca 2 + turbulence and inflammation activation were inhibited by luteolin treatment. Mechanically, luteolin inhibited HNF4 α signaling, which was induced by ER stress. Moreover, luteolin reduced the transcriptional level of HNF4 α downstream gene, such as Asnk4b and HNF1 α. Conversely HNF4 α knockdown abolished the effect of luteolin on β -cell using siRNA. These results suggested the protective effect of luteolin on β -cell was through HNF4 α /Asnk4b pathway. In conclusion, our study discovered that luteolin improved β -cell function and disclosed the underlying mechanism of luteolin on β -cell, suggesting luteolin is a promising agent against pancreatic dysfunction. [ABSTRACT FROM AUTHOR]

Glucagon-like peptide 1 receptor (GLP-1R) agonist (Exendin-4) is a well-known agent used to improve β-cell dysfunctions via protein kinase A (PKA), but the detailed downstream molecular mechanisms are still elusive. We have now found that PKA Cα mediated- TXNIP phosphorylation and degradation played a vital role in the β-cell protective role of exendin-4. After PKA activator (Exendin-4 or FSK) treatment, PKA Cα could directly interact with TXNIP by bimolecular fluorescence complementation and Co-IP assays in INS-1 cells. And PKA Cα overexpression decreased TXNIP level, whereas TXNIP level was largely increased in PKA Cα-KO β-cells by CRISPR-Cas9. Interestingly, TXNIP overexpression or PKA Cα-KO has impaired β-cell functions, including loss of insulin secretion and activation of inflammation. PKA Cα directly phosphorylated TXNIP at Ser307 and Ser308 positions, leading to its degradation via activation of cellular proteasome pathway. Consistent with this observation, TXNIP (S307/308A) mutant resisted the degradation effects of PKA Cα. However, exendin-4 neither affected TXNIP level in TXNIP (S307/308A) mutant overexpressed β-cells nor in PKA Cα-KO β-cells. Moreover, exendin-4 treatment reduced the inflammation gene expression in TXNIP overexpressed β-cells, but exendin-4 treatment has no effect on the inflammation gene expression in TXNIP (S307/308A) overexpressed β-cells. In conclusion, our study reveals the integral role of PKA Cα/TXNIP signaling in pancreatic β-cells and suggests that PKA Cα-mediated TXNIP degradation is vital in β-cell protective effects of exendin-4. [ABSTRACT FROM AUTHOR]

An efficient and practical direct alkenylation of 2‐methylquinolines with aldehydes has been achieved through a novel synergistic organocatalysis. The HOAc‐ activated 2‐methylquiolines undergo a Michael addition to 1,3‐dimethylbarbituric acid‐activated aldehydes, followed by a retro‐Michael addition to release 1,3‐dimethylbarbituric acid and the target products. The transformation produced various 2‐alkenylquinolines with good to excellent yields and featured mild reaction conditions, atom‐ and step‐economy, good functional group tolerance, and operational simplicity. [ABSTRACT FROM AUTHOR]

In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: Improvement of glucose and lipid metabolic dysfunctions is a potent therapeutic strategy against type 2 diabetes mellitus, and identifying new functions for existing drugs may help accelerate the speed of new drug development. Here, we report that latanoprost, a clinical drug for treating primary open-angle glaucoma and intraocular hypertension, effectively ameliorated glucose and lipid disorders in two mouse models of type 2 diabetes. In addition, the glucose-lowering mechanisms of latanoprost were intensively investigated. Methods: A binding-affinity assay and enzymatic tests were used to determine the targets of latanoprost. Cell-based assays on 3T3-L1 adipocytes and C2C12 myotubes and animal model-based assays with db/db and ob/ob mice were further performed to clarify the mechanisms underlying latanoprost-regulated glucose and lipid metabolism. Results: Latanoprost functioned as both an indirect activator of AMP-activated protein kinase and a selective retinoid X receptor α (RXRα) antagonist able to selectively antagonise the transcription of a RXRα/peroxisome proliferator-activated receptor γ heterodimer. It promoted glucose uptake, inhibited pre-adipocyte differentiation and regulated the main genes responsible for glucose and lipid metabolism, including Fas, Scd1, Perilipin (also known as Plin1), Lpl and Pdk4. Chronic administration of latanoprost in mice potently decreased the levels of fasting blood glucose, HbA, fructosamine (FMN), NEFA and total cholesterol, and effectively improved glucose tolerance and glucose/lipid metabolism-related genes in vivo. Conclusions/interpretation: Our studies demonstrate that the existing eye drug latanoprost is both an indirect activator of AMP-activated protein kinase and a selective RXRα antagonist. Latanoprost effectively ameliorated glucose and lipid disorders in diabetic mice, which strongly highlights the potential of latanoprost in the treatment of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

It is demonstrated that natural product vindoline can enhance the glucose-stimulated insulin secretion (GSIS) in MIN6 cells with the EC 50 value of 50.2 μM. In order to improve the activities, a series of vindoline derivatives are synthesized and evaluated in MIN6 cells. Compounds 4 , 8 , 17 and 24 show about 4.5 times more effective stimulation insulin secretion ability (EC 50 : 10.4, 14.2, 11.0 and 12.7 μM, respectively) than vindoline. [ABSTRACT FROM AUTHOR]

Dengue virus (DENV) is the most prevalent arthropod-borne viral disease of humans and has a major impact on global public health. There is no clinically approved drugs for DENV infection. Since intracellular VEGFR2 is increased in DENV infected patients, we thus hypothesized that VEGFR2 participated DENV proliferation and its inhibitors could be served as antivirals against DENV. Actually our results showed that VEGFR2 was induced by DENV infection. Also the agonist of VEGFR2, VEGF-A, promoted DENV proliferation. Therefore, we screened the inhibitors of VEGFR2 and found that brivanib alaninate (brivanib) showed the best anti-DENV ability with the lowest cellular cytotoxicity. Mechanically, our results indicated VEGFR2 directly interacted with PTP1B to dephosphorylate AMPK to provide lipid environment for viral replication. However, this effect could be inhibited by brivanib, which significantly reversed the reduction of AMPK phosphorylation caused by DENV infection, thus improving the cellular lipid environment. Moreover, the antiviral effect of brivanib could be reversed by AMPK inhibitor, Compound C. In addition, oral administration of brivianib (20–50 mg/kg/day) clearly improved the survival rate of DENV2 infection, and this effect was abolished in accompanied with Compound C (10mg/kg/day). Collectively, our study disclosed the mechanism of VEGFR2 in DENV2 and evaluated the antiviral ability of brivanib, which deserved more attention for clinical usage in DENV infection. [Display omitted] [ABSTRACT FROM AUTHOR]