Concurrent binding to DNA and RNA facilitates the pluripotency reprogramming activity of Sox2.

Some transcription factors that specifically bind double-stranded DNA appear to also function as RNA-binding proteins. Here, we demonstrate that the transcription factor Sox2 is able to directly bind RNA in vitro as well as in mouse and human cells. Sox2 targets RNA via a 60-amino-acid RNA binding motif (RBM) positioned C-terminally of the DNA binding high mobility group (HMG) box. Sox2 can associate with RNA and DNA simultaneously to form ternary RNA/Sox2/DNA complexes. Deletion of the RBM does not affect selection of target genes but mitigates binding to pluripotency related transcripts, switches exon usage and impairs the reprogramming of somatic cells to a pluripotent state. Our findings designate Sox2 as a multi-functional factor that associates with RNA whilst binding to cognate DNA sequences, suggesting that it may co-transcriptionally regulate RNA metabolism during somatic cell reprogramming.

Silver-Templated γ-Keggin Alkyltin-Oxo Cluster: Electronic Structure and Optical Limiting Effect.

As one of the most representative polyoxometalate (POM) structures, Keggin clusters have attracted considerable attention. Nevertheless, the noble-metal-templated Keggin structure has not been reported to date. In this work, for the first time, a Ag atom was successfully incorporated to template the formation of a γ-Keggin alkytin-oxo cluster. Moreover, the central Ag atom has brought a significant heavy atom effect, showing the important influence on the electronic structure and optical properties. Theoretical calculations demonstrate that the Ag atom affects the frontier molecular orbitals and excited states of the AgSn12 cluster, and also the process of electron transfer. The solid structure of the AgSn12 cluster exhibits a significant third-order nonlinear optical (NLO) response, and an excellent optical limiting effect has been experimentally verified. The success of this work opens the way for the construction and optical properties modulation of noble metal templated Keggin structures.

A novel nickel-modified nano-magnetite for isolation of histidine-tagged proteins expressed in Escherichia coli.

Nano-magnetite with superparamagnetism could be coated by some organic compounds or by nano Au or Pt via surface modifications with multi-step reactions for the applications of isolating histidine-tagged (His-tagged) proteins. Introducing active sites of binding histidine onto the surface of nano-magnetite was the ultimate task. However, multi-step treatments might result in departure of the coatings from the surface of the nano-magnetite, which led to loss of active sites. In this work, we reported a convenient and efficient way of treating nano-magnetites and applied them in isolating His-tagged proteins. Carboxylates were introduced on the surface of home-made nano-magnetite directly via ultrasonic mixing with sodium bitartrate rather than complicated surface modifications, which was proved by thermogravimetric analyses. Ni2+ was, therefore, caught by the carboxylates of the coating via the coordinate interaction, demonstrated by X-ray photoelectron spectra. The coated magnetic nanoparticles with the bonded Ni2+ were successfully employed to selectively bind and separate recombinant His-tagged proteins directly from the mixture of Escherichia coli cell lysate, and showed wonderful affinity for His-tagged proteins with the saturated adsorption amount being 556 mg g-1. Additionally, such functionalized nano-magnetite manifested the excellent recyclability in isolating His-tagged proteins.

Recent Trends in Potential Therapeutic Applications of the Dietary Flavonoid Didymin.

Didymin (isosakuranetin 7-O-rutinoside) is an orally bioactive dietary flavonoid glycoside first found in citrus fruits. Traditionally, this flavonoid has long been used in Asian countries as a dietary antioxidant. Recent studies have provided newer insights into this pleiotropic compound, which could regulate multiple biological activities of many important signaling molecules in health and disease. Emerging data also presented the potential therapeutic application of dietary flavonoid glycoside didymin against cancer, neurological diseases, liver diseases, cardiovascular diseases, and other diseases. In this review, we briefly introduce the source and extraction methods of didymin, and summarize its potential therapeutic application in the treatment of various diseases, with an emphasis on molecular targets and mechanism that contributes to the observed therapeutic effects. The dietary flavonoid didymin can be used to affect health and disease with multiple therapeutic targets, and it is anticipated that this review will stimulate the future development of this potential dietary medicine.

Oleanane triterpene saponins with cardioprotective activity from Clinopodium polycephalum.

Two new triterpene saponins, clinopodiside VI (1) and saikosaponin c (2), along with six known saikosaponins (3-8), were isolated from the plant of Clinopodium polycephalum. Compounds 1-3 showed moderate inhibition against H9c2 cell damage induced by H2O2.

Soulieoside O, a new cyclolanostane triterpenoid glycoside from Souliea vaginata.

A new cyclolanostane triterpenoid glycoside, soulieoside O (1), together with 25-O-acetylcimigenol-3-O-ß-d-xylopyranoside (2) and cimigenol-3-O-ß-d-xylopyranoside (3), was isolated from the rhizomes of Souliea vaginata. Their structures were characterized by spectroscopic analysis and chemical methods. The new compound showed moderate inhibitory activity against three human cancer cell lines with IC50 values of 9.3-22.5 µM.

Arenobufagin Induces Apoptotic Cell Death in Human Non-Small-Cell Lung Cancer Cells via the Noxa-Related Pathway.

Arenobufagin, an active component isolated from the traditional Chinese medicine Chan Su, exhibits anticancer influences in several human malignancies. However, the effects and action mechanisms of arenobufagin on non-small-cell lung cancer (NSCLC) are still unknown. In this study, we reported that arenobufagin acted through activation of Noxa-related pathways and promoted apoptotic cell death in human NSCLC cells. Our results revealed that arenobufagin-induced apoptosis was caspase-dependent, as evidenced by the fact that caspase-9, caspase-3 and poly (ADP-ribose) polymerase (PARP) were cleaved, and pretreatment with a pan-caspase inhibitor Z-VAD-FMK inhibited the pro-apoptosis effect of arenobufagin. Mechanistically, we further found that arenobufagin rapidly upregulated the expression of the pro-apoptosis protein Noxa, and abrogated the anti-apoptosis protein Mcl-1, a major binding partner of Noxa in the cell. More importantly, the knockdown of Noxa greatly blocked arenobufagin-induced cell death, highlighting the contribution of this protein in the anti-NSCLC effects of arenobufagin. Interestingly, arenobufagin also increased the expression of p53, a direct transcriptional activator for the upregulation of the Noxa protein. Taken together, our results suggest that arenobufagin is a potential anti-NSCLC agent that triggers apoptotic cell death in NSCLC cells through interfering with the Noxa-related pathway.

[Studies on chemical constituents of Clinopodium chinense].

Twenty-eight compounds were isolated and purified from Clinopodium chinense by Sephedax LH-20, ODS, MCI and preparative HPLC. Their structures were identified as apigenin (1), apigenin-7-O-ß-D-glucopyranoside (2), apigenin-7-O-ß-D-glucuronopyranoside (3), thellungianol (4), apigenin-7-O-ß-D-rutinoside (5), luteolin (6), luteolin-4'-O-ß-D-glucopyranoside (7), apigenin-7-O-ß-D-pyranglycuronate butyl ester (8), luteolin-7-O-ß-D-rutinoside (9), luteolin-7-O-ß-D-noehesperidoside (10), acacetin (11), acacetin-7-O-ß-D-glucuronopyranoside (12), buddleoside (13), naringenin (14), pruning (15), nairutin (16), isosakuranetin (17), isosakuranin (18), didymin (19), hesperidin (20), kaempferol (21), quercetin (22), kaempferol-3-O-α-L-rahmnoside (23), p-hydroxycinnamic acid (24), caffeic acid (25), cis-3-[2-[1-(3,4-dihydroxy-phenyl)-1 -hydroxymethyl]-1,3-ben-zodioxol-5-yl]-(E)-2-propenoic acid (26), mesaconic acid (27), gentisic acid 5-O-ß-D-(6'-salicylyl)-glucopyranoside (28). Among them, compounds 7, 9-10, 12, 23, 26-28 were isolated from the Clinopodium for the first time. The protective effects of compounds 1-6, 8-17 and 19 against H2O2-induced H9c2 cardiomyocyte injury were tested, compounds 15 exhibited significantly protective effects. Compared with the cell viability of (62.12±6.18)% in the model, pruning exhibited viabilities of (84.25±7.36)% at 25.0 mg•L⁻¹, respectively, using quercetin as a positive control [cell viability of (84.55±8.26)%, 20 mg•L⁻¹].

A new phenylethanoid glycoside from Incarvillea compacta.

A new phenylethanoid glycoside, 3'''-O-methylcampneoside I (1), was isolated from the 90% ethanolic extract of the roots of Incarvillea compacta, together with three known compounds, campneoside I (2), ilicifolioside A (3), and campneoside II (4). Their structures were determined spectroscopically and compared with previously reported spectral data. Compound 1 existed as epimers and displayed better 1,1-diphenyl-2-picrylhydrazyl (DPPH)-free radical scavenging activity using di-tert-butyl-4-methylphenol (BHT) as the positive control. In addition, pretreatment of human HepG2 cells with compound 1 significantly increased the viability on CCl4-induced cell death.

Compositions, Formation Mechanism, and Neuroprotective Effect of Compound Precipitation from the Traditional Chinese Prescription Huang-Lian-Jie-Du-Tang.

Compounds in the form of precipitation (CFP) are universally formed during the decocting of Chinese prescriptions, such as Huang-Lian-Jie-Du-Tang (HLJDT). The formation rate of HLJDT CFP even reached 2.63% ± 0.20%. The identification by liquid chromatography mass spectrometry (LC-MS(n)) proved that the main chemical substances of HLJDT CFP are baicalin and berberine, which is coincident with the theory that the CFP might derive from interaction between acidic and basic compounds. To investigate the formation mechanism of HLJDT CFP, baicalin and berberine were selected to synthesize a simulated precipitation and then the baicalin-berberine complex was obtained. Results indicated that the melting point of the complex interposed between baicalin and berberine, and the UV absorption, was different from the mother material. In addition, ¹H-NMR integral and high-resolution mass spectroscopy (HR-MS) can validate that the binding ratio was 1:1. Compared with baicalin, the chemical shifts of H and C on glucuronide had undergone significant changes by ¹H-, (13)C-NMR, which proved that electron transfer occurred between the carboxylic proton and the lone pair of electrons on the N atom. Both HLJDT CFP and the baicalin-berberine complex showed protective effects against cobalt chloride-induced neurotoxicity in differentiated PC12 cells. It is a novel idea, studying the material foundation of CFP in Chinese prescriptions.

Antimalarial and Antiproliferative Cassane Diterpenes of Caesalpinia sappan.

Bioassay-guided fractionation of a methanol extract of the seeds of Caesalpinia sappan led to the isolation of 12 new cassane-type diterpenes, caesalsappanins A-L (1-12). Their structures were elucidated on the basis of NMR and HRESIMS analysis, and the absolute configuration of compound 1 was determined by single-crystal X-ray crystallography. All isolated compounds were tested against a chloroquine-resistant Plasmodium falciparum strain for antiplasmodial activities and against a small panel of human cancer cell lines for antiproliferative activities. Compounds 7 and 8 displayed antimalarial activity against the chloroquine-resistant K1 strain of P. falciparum with IC50 values of 0.78 and 0.52 µM and selectivity indices of 17.6 and 16.4, respectively. Compound 10 showed antiproliferative activity against the KB cancer cell line with an IC50 value of 7.4 µM.

[A new bisabolane-type sesquiterpenoid from Coreopsis tinctoria].

To study the chemical constituents of the inflorescences of Coreopsis tinctoria from Xinjiang, isolation and purification of constituents were carried out by column chromatography on macroporous resin (D101) , MCI gel, MDS gel, silica gel, Sephadex LH-20 and semi-preparative HPLC. The structures of the compounds were identified by physicchemical properties and spectral data analysis. Fourteen compounds were isolated and identified as coretinterpenoid A (1), coretinphenol (2), quercetin (3), quercetin-3-O-ß-glucopyranoside (4), luteolin (5), taxifolin (6), 7, 3', 5'-trihydroxyflavanone (7), isookanin (8), isookanin-7-O-ß-D-glucopyranoside (9), 5, 7, 3', 5'-tetrahydroxyflavanone-7-O-ß-D-glucopyranoside (10), butein (11), okanin (12), sulfuretin (13), and linocinnamarin (14). Compound 1 was a new isabolane-type sesquiterpenoid and compounds 4, 10 and 13 were isolated from this plant for the first time.

Two new acylated flavonol glycosides from the seeds of Lepidium sativum.

Two new acylated flavonol glycosides named kaempferol-3-O-(2-O-sinapoyl)-ß-D-galactopyranosyl-(1 → 2)-ß-D-glucopyranoside-7-O-α-L-rhamnopyranoside (1) and quercetin-3-O-(6-O-benzoyl)-ß-D-glucopyranosyl-(1 → 3)-ß-D-galactopyranoside-7-O-α-L-rhamnopyranoside (2), were isolated together with six known compounds from the seeds of L. sativum. Their structures were elucidated on the basis of spectroscopic analysis and chemical methods. In vitro 1 and 2 inhibited nitric oxide production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, with IC50 values of 25.36 and 25.08 µM, respectively.

[Triterpene constituents from Rosa cymosa Tratt].

The constituents in 95% ethanol extract of the root of Rosa cymosa Tratt were purified by column chromatography techniques, leading to isolation of eleven triterpenes. Their structures were elucidated by spectroscopic data as pomolic acid (1), fupenzic acid (2), ursolic acid (3), euscaphic acid (4), arjunic acid (5), tomentic acid (6), 3ß-E-feruloyl corosolic acid (7), 1ß-hydroxyeuscaphic acid (8), myrianthic acid (9), cecropiacic acid (10), and ilexoside B (11). Among them, compounds 3, 6-8, 10 and 11 were obtained from this plant for the first time, and compounds 7 and 10 were obtained from this genus for the first time.

Comparison of chemical composition between imitation wild and transplanted Astragali Radix and their therapeutic effects on heart failure.

ETHNOPHARMACOLOGICAL RELEVANCE: Astragali Radix (AR) is a traditional Chinese herbal medicine, which has been widely used on treating chronic heart failure (CHF) in clinical practice. Two main types of AR in the market are the imitation wild AR (5YAR) and transplanted AR (2YAR). It remains unclear whether there are variations in the anti-heart failure effects of AR with different growth years. Further research is required to explore the material composition and mechanisms of AR in combating heart failure. AIM OF THE STUDY: The aim of the study was to compare the main chemical composition content and the protective effects of 2YAR and 5YAR on heart failure. MATERIALS AND METHODS: Ethanol extracts of 2YAR and 5YAR were prepared, and chemical composition analysis was conducted. C57BL/6 mice were subcutaneously injected with ISO to induce heart failure (HF) and were administrated with a corresponding dose of the extracts of 2YAR and 5YAR by gavage for 28 days. Cardiac function was evaluated using echocardiography. The serum levels of enzymes related to myocardial injury, oxidative stress, and inflammation were detected. The left ventricle was excised for hematoxylin-eosin, Masson, Sirius Red, wheat germ agglutinin, and TUNEL staining. Electron microscopy examination of mitochondrial structure in myocardial cells. Protein expression of monocarboxylate transporter 4 (MCT4), Peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α), phosphorylated AMP-activated protein kinase (p-AMPK), phosphorylated serine/threonine protein kinase (p-AKT), and phosphorylated insulin receptor substrates 1 (p-IRS-1) were detected by immunohistochemistry and western blot. RESULTS: The content of saponins and flavonoids in 5YAR was higher than that in the 2YAR. However, the content of polysaccharides in 5YAR is lower than in 2YAR. The treatment of 2YAR and 5YAR daily for 28 days prevented ISO-induced myocardial damage, including the decrease in serum cardiac enzymes and cardiomyocyte apoptotic index, and improvement in heart function and mitochondrial structure. Additionally, 2YAR and 5YAR reduced serum inflammatory factors and myocardial fibrosis levels. Treatment with 2YAR and 5YAR also decreased MCT4 expression and enhanced PGC-1α, p-AKT, p-AMPK, and p-IRS-1 expression in heart tissues. CONCLUSIONS: The 5YAR was better than 2YAR in anti-heart failure, which may be related to the increase in saponins and flavonoids content. AR exerts anti-heart failure effect by improving mitochondrial function and ameliorating cardiac insulin resistance through activation of the AMPK/PGC1α and IRS/AKT pathways.

Developing a prognostic signature: identifying differentially expressed genes in cardia and non-cardia gastric cancer for immunity and therapeutic sensitivity analysis.

Background: Gastric cancer (GC) can be anatomically categorized into two subtypes; that is, cardia gastric cancer (CGC) and non-cardia gastric cancer (NCGC), which have distinct molecular mechanisms and prognoses. At present, the majority of pharmacological interventions for GC adhere to non-specific treatment regimens. The stratification of GC based on molecular disparities between CGC and NCGC has important clinical guidance value and could help in the development of precision therapies tailored to individual patient needs. Nevertheless, research in this specialized field remains notably limited. This study aims to investigate the molecular differences between CGC and NCGC and to leverage these differences to develop a prognostic risk scoring model (PRSM). Methods: We used patient data from The Cancer Genome Atlas (TCGA) and performed a differentially expressed gene (DEG) analysis between CGC and NCGC. A PRSM was developed from the prognosis-associated DEGs identified through Cox regression analyses and was well validated using Gene Expression Omnibus (GEO) data. Results: A total of 339 DEGs were identified between CGC and NCGC, and four prognosis-associated genes were used to construct the PRSM. Using the risk coefficients and expression levels of signature genes, a median risk score (RS) was calculated to classify patients into high- and low-risk groups. The high-risk group had a significantly worse prognosis than the low-risk group. An in-depth analysis revealed that TP53 mutations were more prevalent in the high-risk group, and MUC16 mutations were more prevalent in the low-risk group. A gene set enrichment analysis (GSEA) and the CIBERSORT algorithm were used to assess the differences in the significantly enriched pathways and immune microenvironment in the high- and low-risk groups, respectively. The inhibitory concentration (IC50) values of the chemotherapy drugs for GC also varied between the two groups. Conclusions: This study elucidated the unique molecular characteristics of GC subtypes based on the anatomical site and provided a preliminary contribution for the development of precision medicine for GC.

Few-shot learning to identify atypical endometrial hyperplasia and endometrial cancer based on transvaginal ultrasonic images.

Objective: It is challenging to accurately distinguish atypical endometrial hyperplasia (AEH) and endometrial cancer (EC) under routine transvaginal ultrasonic (TVU) detection. Our research aims to use the few-shot learning (FSL) method to identify non-atypical endometrial hyperplasia (NAEH), AEH, and EC based on limited TVU images. Methods: The TVU images of pathologically confirmed NAEH, AEH, and EC patients (n = 33 per class) were split into the support set (SS, n = 3 per class) and the query set (QS, n = 30 per class). Next, we used dual pretrained ResNet50 V2 which pretrained on ImageNet first and then on extra collected TVU images to extract 1*64 eigenvectors from the TVU images in SS and QS. Then, the Euclidean distances were calculated between each TVU image in QS and nine TVU images of SS. Finally, the k-nearest neighbor (KNN) algorithm was used to diagnose the TVU images in QS. Results: The overall accuracy and macro precision of the proposed FSL model in QS were 0.878 and 0.882 respectively, superior to the automated machine learning models, traditional ResNet50 V2 model, junior sonographer, and senior sonographer. When identifying EC, the proposed FSL model achieved the highest precision of 0.964, the highest recall of 0.900, and the highest F1-score of 0.931. Conclusions: The proposed FSL model combining dual pretrained ResNet50 V2 eigenvectors extractor and KNN classifier presented well in identifying NAEH, AEH, and EC patients with limited TVU images, showing potential in the application of computer-aided disease diagnosis.

A novel antidepressant homogeneous polysaccharide YLP-1 from Millettia pulchra ameliorates tryptophan metabolism and SCFAs through modulating gut microbiota.

The root of Millettia pulchra (YLS) has been traditionally used as a folk medicine for the treatment of depression and insomnia in the Zhuang nationality of China, and its polysaccharides have potential antidepressant effect. In this study, a novel homogeneous polysaccharide (YLP-1) was purified from the crude polysaccharides of YLS, and it is mainly composed of glucose, arabinose and mannose with molar ratio of 87.25%, 10.77%, and 1.98%, respectively. YLP-1 is a novel α-glucan with the backbone of 1,4-Glcp and branched at C6 of 1,4,6-Glcp to combine 1,4-Manp and 1,5-Araf. The microstructure of YLP-1 displayed a uniform ellipsoidal-like chain morphology and dispersed uniformly in solution. YLP-1 effectively ameliorated depression-like ethological behaviors and restored the decreased catecholamine levels in chronic variable stress (CVS)-induced depression rats. Additionally, it significantly improved the disturbance of gut microbiota induced by CVS stimuli, particularly affecting bacteria that produce short-chain fatty acids (SCFAs), such as bacteria species Lactobacillus spp.. In vitro fermentation study further confirmed that YLP-1 intake could promote SCFAs production by Lactobacillus spp. YLP-1 also mitigated the disruption of tryptophan metabolites in urine and serum. These findings provide evidences for the further development of YLP-1 as a macromolecular antidepressant drug.

Preparative isolation and purification of five flavonoid glycosides and one benzophenone galloyl glycoside from Psidium guajava by high-speed counter-current chromatography (HSCCC).

Psidium guajava leaves have a diverse phytochemical composition including flavonoids, phenolics, meroterpenoids and triterpenes, responsible for the biological activities of the medicinal parts. In particular, flavonol glycosides show beneficial effects on type II diabetes mellitus. A simple and efficient HSCCC method has been developed for the preparative separation of five flavonoid glycosides and one diphenylmethane glycoside from P. guajava. A solvent system composed of n-hexane-ethyl acetate-methanol-water (0.7:4:0.8:4, v/v/v/v) was optimized for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. Under the optimized conditions, hyperoside (15.3 mg), isoquercitrin (21.1 mg), reynoutrin (65.2 mg), quercetin-3-O-ß-D-arabinopyranoside (71.7 mg), quercetin-3-O-α-L-arabinofuranoside (105.6 mg) and 2,4,6-trihydroxy-3,5-dimethylbenzophenone 4-O-(6''-O-galloyl)-ß-D-glucopyranoside (98.4 mg) were separated from crude sample (19.8 g). The structures of all the isolates were identified by ESI-MS, 1H- and 13C-NMR analyses and their purities (>95%) were determined using HPLC.

Two new cycloartane triterpenoid glycosides from the rhizomes of Actaea vaginata.

Two new cycloartane triterpenoid glycosides, soulieoside V (1) and 15-deacetylbeesioside O (2), together with one known compound, beesioside J (3), were isolated from the ethanolic extract of the rhizomes of Actaea vaginata. Their structures were elucidated by spectroscopic methods and by comparison with data reported in the literature. All the compounds were tested for their cytotoxic activities against human cancer cell lines.