Discovery of a novel chemotype as DYRK1A inhibitors against Alzheimer's disease: Computational modeling and biological evaluation.

Dual-specificity tyrosine phosphorylation-regulated kinase 1 A (DYRK1A) plays an essential role in Tau and Aß pathology closely related to Alzheimer's disease (AD). Accumulative evidence has demonstrated DYRK1A inhibition is able to reduce the pathological features of AD. Nevertheless, there is no approved DYRK1A inhibitor for clinical use as anti-AD therapy. This is somewhat due to the lack of effective and safe chemotypes of DYRK1A inhibitors. To address this issue, we carried out in silico screening, in vitro assays and in vivo efficacy evaluation with the aim to discover a new class of DYRK1A inhibitors for potential treatment of AD. By in silico screening, we selected and purchased 16 potential DYRK1A inhibitors from the Specs chemical library. Among them, compound Q17 (Specs ID: AO-476/40829177) potently inhibited DYRK1A. The hydrogen bonds between compound Q17 and two amino acid residues named GLU239 and LYS188, were uncovered by molecular docking and molecular dynamics simulation. The cell-based assays showed that compound Q17 could protect the SH-SY5Y human neuroblastoma cell line from okadaic acid (OA)-induced injury by targeting DYRK1A. More importantly, compound Q17 significantly improved cognitive dysfunction of 3 × Tg-AD mice, ameliorated pathological changes, and attenuated Tau hyperphosphorylation as well as Aß deposition. In summary, our computational modeling strategy is effective to identify novel chemotypes of DYRK1A inhibitors with great potential to treat AD, and the identified compound Q17 in this study is worthy of further study.

Nickel-Catalyzed Cross-Coupling Reaction of Aryl Bromides/Nitriles with Imidazolium Salts Involving Inert C-N Bond Cleavage.

We herein present a nickel-catalyzed cross-coupling reaction of aryl halides and nitriles with imidazolium salts. A series of 2-arylated imidazoles could be obtained in moderate to good yields through inert C-N bond cleavage. The imidazolium salt in this reaction acts as both a coupling partner and N-heterocyclic carbene (NHC) ligand precursor. Mechanistic studies reveal that consecutive steps of migratory insertion of the NHC into the aryl C-Ni bond and ß-C elimination might be involved in the proposed reaction mechanism.

Biosynthesis of Epipyrone A Reveals a Highly Specific Membrane-Bound Fungal C-Glycosyltransferase for Pyrone Galactosylation.

Epipyrone A is a unique C-galactosylated 4-hydroxy-2-pyrone derivative with an antifungal potential from the fungus Epicoccum nigrum. We elucidated its biosynthesis via heterologous expression and characterized an unprecedented membrane-bound pyrone C-glycosyltransferase biochemically. Molecular docking and mutagenesis experiments suggested a possible mechanism for the heterocyclic C-glycosylation and the importance of a transmembrane helix for its catalysis. These results expand the repertoire of C-glycosyltransferases and provide new insights into the formation of C-glycosides in fungi.

Induced Self-Assembly of Vitamin E-Spermine/siRNA Nanocomplexes via Spermine/Helix Groove-Specific Interaction for Efficient siRNA Delivery and Antitumor Therapy.

Gene therapy has been one of potential strategies for the treatment of different diseases, where efficient and safe gene delivery systems are also extremely in need. Current lipid nanoparticles (LNP) technology highly depends on the packing and condensation of nucleic acids with amine moieties. Here, an attempt to covalently link two natural compounds, spermine and vitamin E, is made to develop self-assembled nucleic acid delivery systems. Among them, the spermine moieties specifically interact with the major groove of siRNA helix through salt bridge interaction, while vitamin E moieties are located around siRNA duplex. Such amphiphilic vitamin E-spermine/siRNA complexes can further self-assemble into nanocomplexes like multiblade wheels. Further studies indicate that these siRNA nanocomplexes with the neutrally charged surface of vitamin E can enter cells via caveolin/lipid raft mediated endocytosis pathway and bypass lysosome trapping. With these self-assembled delivery systems, efficient siRNA delivery is successfully achieved for Eg5 and Survivin gene silencing as well as DNA plasmid delivery. Further in vivo study indicates that VE-Su-Sper/DSPE-PEG2000/siSurvivin self-assembled nanocomplexes can accumulate in cancer cells and gradually release siRNA in tumor tissues and show significant antitumor effect in vivo. The self-assembled delivery system provides a novel strategy for highly efficient siRNA delivery.

Evaluation of A-ring hydroxymethylene-amino- triterpenoids as inhibitors of SARS-CoV-2 spike pseudovirus and influenza H1N1.

A set of triterpene A-ring hydroxymethylene-amino-derivatives was synthesized and their antiviral activity was studied. The synthesized compounds were tested for their potential inhibition of SARS-CoV-2 pseudovirus in BHK-21-hACE2 cells and influenza A/PuertoRico/8/34 (H1N1) virus in MDCK cell culture. Compounds 6, 8 and 19 showed significant anti-SARS-CoV-2 pseudovirus activity with EC50 value of 3.20-11.13 µM, which is comparable to the positive control amodiaquine (EC50 3.17 µM). Among them, 28-O-imidazolyl-azepano-betulin 6 and C3-hydroxymethylene-amino-glycyrrhetol-11,13-diene 19 were identified as the lead compounds with SI values of 7 and 10. The binding mode of compound 6 into the RBD domain of SARS-CoV-2 spike glycoprotein (PDB code: 7DK3) by docking and molecular dynamics simulation was investigated.

Antiviral opportunities of Mannich bases derived from triterpenic N-propargylated indoles.

Oleanolic and glycyrrhetic acids alkyne derivatives were synthesized as a result of propargylation of the indole NH-group condensed with the triterpene A-ring, the following aminomethylation led to a series of Mannich bases. The synthesized compounds were tested for their potential inhibition of influenza A/PuertoRico/8/34 (H1N1) virus in Madin-Darby canine kidney (MDCK) cell culture and SARS-CoV-2 pseudovirus in baby hamster kidney-21-human angiotensin-converting enzyme 2 (BHK-21-hACE2) cells. Mannich bases of oleanolic and glycyrrhetic acids N-propargylated indoles 7, 8, and 12 were the most efficacious against influenza virus A with IC50 7-10 µM together with a low toxicity (CC50 > 145 µM) and high selectivity index SI value 20. Indolo-oleanolic acid morpholine amide Mannich base holding N-methylpiperazine moiety 9 showed anti-SARS-CoV-2 pseudovirus activity with EC50 value of 14.8 µM. Molecular docking and dynamics modeling investigated the binding mode of the compounds 7 and 12 into the binding pocket of influenza A virus M2 protein and compound 9 into the RBD domain of SARS-CoV-2 spike glycoprotein.

Aryl boronic acid-controlled divergent ring-contraction and ring-opening/isomerization reaction of tert-cyclobutanols enabled by nickel catalysis.

In this work, we wish to present a nickel-catalyzed divergent ring-contraction and ring-opening/isomerization reaction of tert-cyclobutanols. The key to control these two different reaction pathways is to choose appropriate boronic acid, where the use of phenylboronic acid and pyrimidin-5-ylboronic acid enables a ring-contraction and ring-opening reaction/isomerization, respectively. Both cyclopropyl aryl methanones and 1-aryl butan-1-ones could be selectively obtained.

Structural characteristics and biological activity of lactic acid bacteria exopolysaccharides separated by ethanol/(NH4)2SO4 ATPS.

Exopolysaccharides (EPS) from lactic acid bacteria (LAB) as edible and safe bioproducts with health benefits have become an interesting topic. In this study, aqueous two-phase system (ATPS) was established using ethanol and (NH4)2SO4 as phase-forming substances to separate and purify LAB EPS from Lactobacillus plantarum 1.0665. The operating conditions were optimized by a single factor and response surface method (RSM). The results indicated that an effectively selective separation of LAB EPS was achieved by the ATPS consisted of 28 % (w/w) ethanol and 18 % (w/w) (NH4)2SO4 at pH 4.0. Under optimized conditions, the partition coefficient (K) and recovery rate (Y) were well matched with the predicted value of 3.83 ± 0.019 and 74.66 ± 1.05 %. The physicochemical properties of purified LAB EPS were characterized by various technologies. According to the results, LAB EPS was a complex polysaccharide with a triple helix structure mainly composed of mannose, glucose and galactose in the molar ratio of 1.00: 0.32: 0.14, and it proved that the ethanol/(NH4)2SO4 system had good selectivity for LAB EPS. In addition, LAB EPS displayed excellent antioxidant activity, antihypertension activity, anti-gout capacity and hypoglycemic activity in vitro analysis. The results suggested that LAB EPS could be a dietary supplement applied in functional foods.

Nickel-catalyzed divergent formylation and carboxylation of aryl halides with isocyanides.

Herein, we describe a nickel-catalyzed divergent formylation and carboxylation reaction of aryl halides with isocyanides. A rich array of aromatic aldehydes and carboxylic acids can be, respectively, accessed in moderate to good yields. Some sensitive functional groups such as hydroxyl, iodine, cyano, and indolyl are fairly tolerant of nickel catalysis. In the carboxylation reactions, the combination of isocyanide and H2O is first employed as a promising carbonyl surrogate instead of gaseous CO and CO2.

Immune checkpoints expression patterns in early-stage triple-negative breast cancer predict prognosis and remodel the tumor immune microenvironment.

Background: Currently, targeting immune checkpoint molecules holds great promise for triple-negative breast cancer (TNBC). However, the expression landscape of immune checkpoint genes (ICGs) in TNBC remains largely unknown. Method: Herein, we systematically investigated the ICGs expression patterns in 422 TNBC samples. We evaluated the ICGs molecular typing based on the ICGs expression profile and explored the associations between ICGs molecular subtypes and tumor immune characteristics, clinical significance, and response to immune checkpoint inhibitors (ICIs). Results: Two ICGs clusters and two ICGs-related gene clusters were determined, which were involved in different survival outcomes, biological roles and infiltration levels of immune cells. We established a quantification system ICGs riskscore (named IRS) to assess the ICGs expression patterns for individuals. TNBC patients with lower IRS were characterized by increased immune cell infiltration, favorable clinical outcomes and high sensitivity to ICIs therapy. We also developed a nomogram model combining clinicopathological variables to predict overall survival in TNBC. Genomic feature analysis revealed that high IRS group presented an increased tumor mutation burden compared with the low IRS group. Conclusion: Collectively, dissecting the ICGs expression patterns not only provides a new insight into TNBC subtypes but also deepens the understanding of ICGs in the tumor immune microenvironment.

The structure-based optimization of 3-substituted indolin-2-one derivatives as potent and isoform-selective c-Jun N-terminal kinase 3 (JNK3) inhibitors and biological evaluation.

An indolin-2-(4-thiazolidinone) scaffold was previously shown to be a novel chemotype for JNK3 inhibition. However, more in vivo applications were limited due to the unconfirmed configuration and poor physicochemical properties. Here, the indolin-2-(4-thiazolidinone) scaffold validated the absolute configuration; substituents on the scaffold were optimized. Extensive structure activity relationship (SAR) studies were performed using kinase activity assays, thus leading to potent and highly selective JNK3 inhibitors with neuroprotective activity and good oral bioavailability. One lead compound, A53, was a potent and selective JNK3 inhibitor (IC50 = 78 nM) that had significant inhibition (>80% at 1 µM) to only JNK3 in a 398-kinase panel. A53 had low inhibition against JNK3 and high stability (t1/2(α) = 0.98 h, t1/2(ß) = 2.74 h) during oral administration. A modeling study of A53 in human JNK3 showed that the indolin-2-(4-thiazolidinone)-based JNK3 inhibitor with a 5-position-substituted hydrophilic group offered improved kinase inhibition.

MiR-21-5p protects against ischemic stroke by targeting IL-6R.

Background: Ischemic stroke is a brain dysfunction disease caused by vascular obstruction. The expression of many kinds of microRNAs (miRNAs) is related to ischemic stroke. MiRNA has the ability to reduce or save ischemic injury. Therefore, we aimed to explore the protective miRNA in the ischemia-reperfusion process. Methods: The Gene Expression Omnibus (GEO) peripheral RNA sequencing (RNA-seq) datasets of ischemic stroke patients were analyzed to search for differentially expressed miRNAs in the ischemia-reperfusion process. The expression level of miRNA in 60 patients with ischemic stroke and 23 age-matched healthy control inpatients was tested by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The significantly changed miRNAs were verified through comparison of the peripheral blood of healthy people and patients of the hospital. The in-vitro ischemia-reperfusion model was established through oxygen-glucose deprivation (OGD) treated HEMC-1 cells. The cell viabilities and cell apoptosis are detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, respectively. Apoptosis-related proteins including Bcl-2, Bax, caspase-3, and caspase-9 expression levels were verified by western blot. Predict the combination of hsa-miR-21-5p and interleukin-6 receptor (IL-6R) through TargetScan database, clone the 2964-2961 site of IL-6R-3'-untranslated region (3'-UTR), establish IL-6R-3'-UTR and IL-6R-3'-UTR mutant plasmids, copy and clone wild type and mutant IL-6R-3'-UTR into luciferase report vector pGL3 respectively, and detect the activity of luciferase. The expression of hsa-miR-21-5p was regulated by using hsa-miR-21-5p mimic and hsa-miR-21-5p inhibitor. Results: Through RNA-seq analysis, it was revealed that "hsa-miR-548ar-3p", "hsa-miR-651-5p", "hsa-miR-142-3p", "hsa-miR-21-5p", and "hsa-miR-30e-5p" were notably lower in ischemia patients, and that "hsa-miR-21-5p" was significantly decreased in the peripheral blood of hospital patients. Luciferase assay showed that hsa-miR-21-5p could directly bind to the 3'-UTR of the IL-6R gene and inhibit IL-6R translation; the level of IL-6R was also elevated in patients. In the OGD-treated HMEC-1 cells, overexpressed hsa-miR-21-5p mimic could enhance cell viabilities and decrease cell apoptosis. Moreover, IL-6R overexpression could reduce the protective effects of hsa-miR-21-5p. Conclusions: In the peripheral blood of ischemia patients, hsa-miR-21-5p is significantly decreased and IL-6R is elevated. The "hsa-miR-21-5p" could bind to the IL-6R gene and suppress IL-6R expression, thus alleviating the damage of OGD treatment in HMEC-1 cells.

Dual degradation mechanism of GPX4 degrader in induction of ferroptosis exerting anti-resistant tumor effect.

Targeting Glutathione peroxidase 4 (GPX4) has become a promising strategy for drug-resistant cancer therapy via ferroptosis induction. It was found that the GPX4 inhibitors such as RSL3 have GPX4 degradation ability via not only autophagy-lysosome pathway but also ubiquitin-proteasome system (UPS). Proteolysis targeting chimeras (PROTACs) using small molecule with both inhibition and degradation ability as the ligand of protein of interest (POI) have not been reported. To obtain better compounds with effective disturbance of GPX4 activity, and compare the difference between GPX4 inhibitors with degradation ability and their related PROTACs, we designed and synthesized a series of GPX4 degraders using PROTAC technology in terms of its excellent characteristics such as high efficiency and selectivity and the capacity of overcoming resistance. Hence, 8e was discovered as a potent and highly efficacious GPX4 degrader based upon the inhibitor RSL3. It was 2-3 times more potent than RSL3 in all the in vitro anti-tumor assays, indicating the importance of the PROTAC ternary complex of GPX4, 8e and E3 ligase ligand. 8e revealed better potency in resistant tumor cells than in wide type cells. Furthermore, we discovered for the first time that degrader 8e exhibit GPX4 degradation activity via ubiquitin-proteasome system (UPS) and autophagy-lysosome pathway with UPS plays the major role in the process. Our data also suggested that 8e and RSL3 could potently induce ferroptosis of HT1080 cells via GPX4 inhibition and degradation. In summary, our data revealed that the GPX4 degrader 8e achieves better degradation and anti-tumor effects compared to its related GPX4 inhibitor RSL3. Thus, an efficient strategy to induce GPX4 degradation and subsequent ferroptosis was established in this study for malignant cancer treatment in the future.

Systematic Investigation of the Multifaceted Role of SOX11 in Cancer.

SRY-box transcription factor 11 (SOX11), as a member of the SOX family, is a transcription factor involved in the regulation of specific biological processes and has recently been found to be a prognostic marker for certain cancers. However, the roles of SOX11 in cancer remain controversial. Our study aimed to explore the various aspects of SOX11 in pan-cancer. The expression of SOX11 was investigated by the Genotype Tissue-Expression (GTEX) dataset and the Cancer Genome Atlas (TCGA) database. The protein level of SOX11 in tumor tissues and tumor-adjacent tissues was verified by human pan-cancer tissue microarray. Additionally, we used TCGA pan-cancer data to analyze the correlations among SOX11 expression and survival outcomes, clinical features, stemness, microsatellite instability (MSI), tumor mutation burden (TMB), mismatch repair (MMR) related genes and the tumor immune microenvironment. Furthermore, the cBioPortal database was applied to investigate the gene alterations of SOX11. The main biological processes of SOX11 in cancers were analyzed by Gene Set Enrichment Analysis (GSEA). As a result, aberrant expression of SOX11 has been implicated in 27 kinds of cancer types. Aberrant SOX11 expression was closely associated with survival outcomes, stage, tumor recurrence, MSI, TMB and MMR-related genes. In addition, the most frequent alteration of the SOX11 genome was mutation. Our study also showed the correlations of SOX11 with the level of immune infiltration in various cancers. In summary, our findings underline the multifaceted role and prognostic value of SOX11 in pan-cancer.

Nickel-catalyzed cascade hydrosilylation/cyclization of 1,7-enynes leading to silyl-containing quinolinones.

We herein describe a nickel-catalyzed cascade hydrosilylation/cyclization reaction of 1,7-enynes with bulky triphenylsilane. A series of silyl-containing quinolinone derivatives are obtained in good to excellent yields under mild reaction conditions. This reaction also features excellent chemoselectivity, broad functional group tolerance, and gram-scale synthesis.

Concise Biosynthesis of Tropone-Containing Spiromaterpenes by a Sesquiterpene Cyclase and a Multifunctional P450 from a Deep-Sea-Derived Spiromastix sp. Fungus.

Spiromaterpenes are a group of rare tropone-containing sesquiterpenes with antineuroinflammatory activity. Herein, we elucidate their biosynthetic pathway in a deep-sea-derived Spiromastix sp. fungus by heterologous expression, biochemical characterization, and incubation experiments. The sesquiterpene cyclase SptA was first characterized to catalyze the production of guaia-1(5),6-diene, and a multifunctional cytochrome P450 catalyzed the tropone ring formation. These results provide important clues for the rational mining of bioactive guaiane-type sesquiterpenes and expand the repertoire of P450 activities to synthesize unique building blocks of natural products.

Combination of Immune-Related Network and Molecular Typing Analysis Defines a Three-Gene Signature for Predicting Prognosis of Triple-Negative Breast Cancer.

Recent breakthroughs in immune checkpoint inhibitors (ICIs) have shown promise in triple-negative breast cancer (TNBC). Due to the intrinsic heterogeneity among TNBC, clinical response to ICIs varies greatly among individuals. Thus, discovering rational biomarkers to select susceptible patients for ICIs treatment is warranted. A total of 422 TNBC patients derived from The Cancer Genome Atlas (TCGA) database and Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) dataset were included in this study. High immunogenic gene modules were identified using weighted gene co-expression network analysis (WGCNA). Immune-related genes (IRGs) expression patterns were generated by consensus clustering. We developed a three-gene signature named immune-related gene panel (IRGP) by Cox regression method. Afterward, the associations of IRGP with survival outcomes, infiltration of immune cells, drug sensitivity, and the response to ICIs therapy were further explored. We found five high immunogenic gene modules. Two distinct IRGclusters and IRG-related genomic clusters were identified. The IRGP was constructed based on TAPBPL, FBP1, and GPRC5C genes. TNBC patients were then subdivided into high- and low-IRGriskscore subgroups. TNBC patients with low IRGriskscore had a better survival outcome, higher infiltration of immune cells, lower TP53 mutation rate, and more benefit from ICIs treatment than high IRGriskscore patients. These findings offer novel insights into molecular subtype of TNBC and provided potential indicators for guiding ICIs treatment.

Nickel-catalyzed cyanation reaction of aryl/alkenyl halides with alkyl isocyanides.

We herein describe a nickel-catalyzed cyanation reaction of aryl/alkenyl halides with alkyl isocyanides. Both aryl/alkenyl iodines and bromides were found to be competent electrophiles that reacted with alkyl isocyanides, affording nitrile compounds in moderate to good yields. A range of functional groups including halogens as well as hydroxyl, formyl, and acetamino groups were fairly compatible with the nickel catalysis. This protocol featured broad functional group tolerance, simple reaction conditions, and gram-scale synthesis.

Di(2-ethylhexyl) phthalate disturbs cholesterol metabolism through oxidative stress in rat liver.

Di(2-ethylhexyl) phthalate (DEHP) is widely used and has been implicated in hepatotoxicity, although the mechanism is unclear. Here, we investigated the effect of DEHP on hepatic cholesterol metabolism in SD rats exposed to 0 and 300 mg/kg/day DEHP for 12 weeks. An RNA-Seq analysis was performed to describe the hepatic responses to long-term DEHP exposure in combination with serological and oxidative stress parameter measurements. DEHP increased the serum levels of total cholesterol (TC), high-density lipoprotein (HDL), and alanine transaminase (ALT). Moreover, DEHP increased the content of malondialdehyde (MDA) and decreased antioxidant enzyme activities in the liver. Transcriptomic results revealed that DEHP dramatically changed the cholesterol metabolism pathway and oxidation-reduction process and depressed gene expression involved in cholesterol efflux and monooxygenase activity. Total antioxidant capacity (T-AOC) positively correlated with Abcg5 and Abcg8. Overall, this study showed the mechanisms underlying hepatotoxicity caused by DEHP, providing new insights into understanding DEHP poisoning.