Molecular characterization and structure basis of a malonyltransferase with both substrate promiscuity and catalytic regiospecificity from Cistanche tubulosa.

Enzymatic malonylation of natural glycosides provides a promising alternative method for drug-like malonylated glycosides supply. However, the catalytic potential and structural basis of plant malonyltransferase are far from being fully elucidated. This work identified a new malonyltransferase CtMaT1 from Cistanche tubulosa. It displayed unprecedented mono- and/or di-malonylation activity toward diverse glucosides with different aglycons. A "one-pot" system by CtMaT1 and a malonyl-CoA synthetase was established to biosynthesize nine new malonylated glucosides. Structural investigations revealed that CtMaT1 possesses an adequately spacious acyl-acceptor pocket capable of accommodating diverse glucosides. Additionally, it recognizes malonyl-CoA through strong electrotactic and hydrogen interactions. QM/MM calculation revealed the H167-mediated SN2 reaction mechanism of CtMaT1, while dynamic simulations detected the formation of stable hydrogen bonds between the glucose-6-OH group and H167, resulting in its high malonylation regiospecificity. Calculated energy profiles of two isomeric glycosides highlighted lower reaction energy barriers towards glucoside substrates, emphasizing CtMaT1's preference for glucosides. Furthermore, a mutant CtMaT1H36A with notably increased di-malonylation activity was obtained. The underlying molecular mechanism was illuminated through MM/GBSA binding free energy calculation. This study significantly advances the understanding of plant acyltransferases from both functional and protein structural perspectives, while also providing a versatile tool for enzymatic malonylation applications in pharmacology.

Methionine-choline deficient diet deteriorates DSS-induced murine colitis through disturbance of gut microbes and infiltration of macrophages.

Ulcerative colitis (UC) is associated with changed dietary habits and mainly linked with the gut microbiota dysbiosis, necroptosis of epithelial cells, and mucosal ulcerations. Liver dysfunction and abnormal level of liver metabolism indices were identified in UC patients, suggesting a close interaction between gut and liver disorders. Methionine-choline deficient diet (MCD) has been shown to induce persistent alterations of gut microbiota and metabolome during hepatitis. In this study we further explored the disease phenotypes in UC patients and investigated whether MCD functioned as a trigger for UC susceptibility. After assessing 88 serum specimens from UC patients, we found significant liver dysfunction and dyslipidemia including abnormal ALT, AST, TG, TC, LDL-c and HDL-c. Liver dysfunction and dyslipidemia were confirmed in DSS-induced colitis mice. We fed mice with MCD for 14 days to cause mild liver damage, and then treated with DSS for 7 days. We found that MCD intake significantly exacerbated the pathogenesis of mucosal inflammation in DSS-induced acute, progressive, and chronic colitis, referring to promotion of mucosal ulcers, colon shortening, diarrhea, inflammatory immune cell infiltration, cytokines release, and abnormal activation of inflammatory macrophages in colon and liver specimens. Intraperitoneal injection of clodronate liposomes to globally delete macrophages dramatically compromised the pathogenesis of MCD-triggering colitis. In addition, MCD intake markedly changed the production pattern of short-chain fatty acids (SCFAs) in murine stools, colons, and livers. We demonstrated that MCD-induced colitis pathogenesis largely depended on the gut microbes and the disease phenotypes could be transmissible through fecal microbiota transplantation (FMT). In conclusion, this study supports the concept that intake of MCD predisposes to experimental colitis and enhances its pathogenesis via modulating gut microbes and macrophages in mice.

Osteonectin bidirectionally regulates osteoblast mineralization.

OBJECTIVE: The aim of this study was to investigate whether Osteonectin/Secreted protein acidic and rich in cysteine (ON/SPARC) had a two-way dose-dependent regulatory effect on osteoblast mineralization and its molecular mechanism. METHODS: Initially, different concentrations of ON were added in osteoblasts, and the gene of bone sialoprotein (BSP), osteocalcin (OCN), osteopontin (OPN) and alkaline phosphatase (ALP) were detected using reverse-transcription quantitative polymerase chain reaction (RT-PCR). Secondly, based on the above results, the Optima and inhibitory concentration of ON for osteoblast mineralization were determined and regrouped, the Control group was also set up, and the gene detections of Collagen 1 (Col 1), Discoidin domain receptor 2 (DDR2) and p38 mitogen­activated protein kinase were added using RT-PCR. In the third stage of the experiment, osteoblasts were pretreated with 0.4Mm ethyl-3,4-dihydroxybenzoate (DHB) (a specific inhibitor of collagen synthesis) for 3 h before adding the optima SPARC, the gene and protein expressions of OCN, OPN, BSP, ALP, DDR2, ALP, Col 1, DDR2 and P38 were detected by RT­qPCR and western blot analysis, and the mineralized nodules were observed by alizarin red staining. RESULTS: The results showed that the expression of OCN, OPN, BSP, ALP, DDR2, ALP, Col 1, DDR2 and P38 genes and proteins in osteoblasts were significantly enhanced by 1 ug/ml ON, 100 ug/ml ON or 1 ug/ml ON added with 3,4 DHB significantly inhibited the expressions of DDR2, P38 and the above-mentioned mineralization indexes, and significantly reduced the formation of mineralized nodules. CONCLUSION: This study suggested that ON had a bidirectional dose-dependent regulatory effect on osteoblast mineralization, and the activation of P38 pathway by collagen binding to DDR2 was also an important molecular mechanism.

Identification of the key genes of tuberculosis and construction of a diagnostic model via weighted gene co-expression network analysis.

BACKGROUND: Tuberculosis (TB) is an infectious disease with high mortality, and mining key genes for TB diagnosis is vital to raise the survival rate of patients. METHODS: The whole microarray datasets GSE83456 (training set) and GSE19444 (validation set) of TB patients were downloaded from the Gene Expression Omnibus (GEO) database. Differential expression was conducted on genes between TB and normal samples (unconfirmed TB) in GSE83456 to yield TB-related differentially expressed genes (DEGs). DEGs were subjected to weighted gene co-expression network analysis (WGCNA) and clustered to form distinct gene modules. The immune scores of 25 kinds of immune cells were obtained by single-sample gene set enrichment analysis (ssGSEA) of TB samples, and Pearson correlation analysis was carried out between the 25 immune scores and diverse gene modules. The gene modules significantly associated with immune cells were retained as Target modules. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed on the genes in the modules (p-value <0.05). The protein-protein interaction (PPI) network was established utilizing the STRING database for genes in the Target module, and the selected key genes were intersected with immune-related genes in the ImmPort database. The obtained immune-related module genes were used for subsequent least absolute shrinkage and selection operator (LASSO) regression analysis and diagnostic models were constructed. Finally, the receiver operating characteristic (ROC) curve was utilized to validate the diagnostic model. RESULTS: The turquoise and yellow modules had a high correlation with macrophages. LASSO regression analysis of immune-related genes in TB was carried on to finally construct a 5-gene diagnostic model composed of C5, GRN, IL1B, IL23A, and TYMP. As demonstrated by the ROC curves, the diagnostic efficiency of this diagnostic model was 0.957 and 0.944 in the training and validation sets, respectively. Therefore, the immune-related 5-gene model had a good diagnostic function for TB. CONCLUSION: We identified 5 immune-related diagnostic markers that may play an important role in TB, and verified that this immune-related key gene model had a good diagnostic performance.

Enzymatic biosynthesis of novel 2-(2-phenylethyl)chromone glycosides catalyzed by UDP-glycosyltransferase UGT71BD1.

2-(2-Phenylethyl)chromones (PECs) are the main bioactive components of agarwood which showed diverse pharmaceutical activities. Glycosylation is a useful structural modification method to improve compounds' druggability. However, PEC glycosides were rarely reported in nature which largely limited their further medicinal investigations and applications. In this study, the enzymatic glycosylation of four naturally separated PECs 1-4 was achieved using a promiscuous glycosyltransferase UGT71BD1 identified from Cistanche tubulosa. It could accept UDP-Glucose, UDP-N-acetylglucosamine and UDP-xylose as sugar donors and conduct the corresponding O-glycosylation of 1-4 with high conversion efficiencies. Three O-glucosylated products 1a (5-hydroxy-2-(2-phenylethyl)chromone 8-O-ß-D-glucopyranoside), 2a (8-chloro-2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) and 3a (2-(2-phenylethyl)chromone 6-O-ß-D-glucopyranoside) were prepared and structurally elucidated as novel PEC glucosides based on NMR spectroscopic analyses. Subsequent pharmaceutical evaluation found that 1a showed remarkably improved cytotoxicity against HL-60 cells, whose cell inhibition rate was 19 times higher than that of its aglycon 1. The IC50 value of 1a was further determined to be 13.96 ± 1.10 µM, implying its potential as a promising antitumor-leading candidate. To improve the production of 1, docking, simulation and site-directed mutagenesis were performed. The important role of P15 in the glucosylation of PECs was discovered. Besides, a mutant K288A with a two-fold increased yield for 1a production was also afforded. This research reported the enzymatic glycosylation of PECs for the first time, and also provide an eco-friendly pathway for the alternative production of PEC glycosides for leading compounds discovery.

Identification of Diagnostic Markers in Synovial Tissue of Osteoarthritis by Weighted Gene Coexpression Network.

Osteoarthritis (OA) is a serious threat to human health. However, the etiology and pathogenesis of the disease are not fully understood. Most researchers believe that the degeneration and imbalance of articular cartilage, extracellular matrix, and subchondral bone are the fundamental causes of osteoarthritis. However, recent studies have shown that synovial lesions may precede cartilage, which may be an important precipitating factor in the early stage of OA and the whole course of the disease. This study aimed to conduct an analysis based on sequence data from the Gene Expression Omnibus (GEO) database to investigate the presence of effective biomarkers in the synovial tissue of osteoarthritis for the diagnosis and control of OA progression. In this study, the differentially expressed OA-related genes (DE-OARGs) in osteoarthritis synovial tissues were extracted in the GSE55235 and GSE55457 datasets using the Weighted Gene Co-expression Network Analysis (WGCNA) and limma. Least-Absolute Shrinkage and Selection Operator (LASSO) algorithm was used to select the diagnostic genes based on the DE-OARGs by glmnet package. 7 genes were selected as diagnostic genes including SAT1, RLF, MAFF, SIK1, RORA, ZNF529, and EBF2. Subsequently, the diagnostic model was constructed and the results of the Area Under the Curve (AUC) demonstrated that the diagnostic model had high diagnostic performance for OA. Additionally, among the 22 immune cells of the Cell type Identification By Estimating Relative Subsets Of RNA Transcripts (CIBERSORT) and the 24 immune cells of the single sample Gene Set Enrichment Analysis (ssGSEA), 3 immune cells and 5 immune cells were different between the OA and normal samples, respectively. The expression trends of the 7 diagnostic genes were consistent in the GEO datasets and the results of the real-time reverse transcription PCR (qRT-PCR). The results of this study demonstrate that these diagnostic markers have important significance in the diagnosis and treatment of OA, and will provide further evidence for the clinical and functional studies of OA.

Laryngeal contact granuloma after radiotherapy in patients with nasopharyngeal carcinoma: a case series.

Background: Laryngeal contact granuloma (LCG) is a benign hypertrophic lesion and phonatory injury after abnormal vocal behavior is regarded as its major etiology. Patients receiving radiation for non-laryngeal head and neck tumors are troubled by persistent voice impairment. The occurrence of LCG after radiotherapy for nasopharyngeal carcinoma (NPC) in our practice has implored us to re-exam their underlying etiology. We hypothesize that a proportion of LCG results from voice change caused by non-laryngeal head and neck cancer radiotherapy and firstly describe a distinct LCG population originated after radiotherapy for NPC with respect to the clinical profile, presentation, prognosis and response to treatment of patients. Methods: We retrospectively reviewed the laryngoscopic examination and tumor study findings to elucidate the common clinical features of patients who presented with LCG after radiotherapy for NPC. All patients were regularly monitored with telescopic examination until lesions disappeared. Data on age, sex, clinical presentation, telescopic findings, management, latency time of lesion formation, remission time and clinical outcome were reviewed. Results: The medical review identified 27 cases of LCG secondary to radiotherapy for NPC. All lesions had been diagnosed during routine endoscopy following radiation. The interval between radiation onset and endoscopic diagnosis was 3.77 months (range, 0.67-11 months). 20 cases were resolved through simple observation, 4 cases were resolved with the administration of proton pump inhibitors (PPIs), and 3 cases with a poor response to PPI therapy required subsequent surgical resection. The mean remission time in the observation and PPI groups was 4.42 months (range, 0.73-18.9 months) and 5.78 months (range, 2.17-14.63 months), respectively. All patients recovered completely and none experienced recurrence during a mean follow-up of 32.44 months (range, 5.6-71.67 months). Conclusions: Iatrogenic granulomas of vocal process are presenting after radiation for non-laryngeal head and neck cancers. In contrast with spontaneous granulomas, these granulomas can be cured at high remission rates and low recurrence trend without specific intervention. Thus, simple observation may be sufficient for radiation-induced LCG.

The clinical effect of trochanteric slide osteotomy combined with a cementless femoral conical stem in total hip replacement for the treatment of Crowe type IV developmental dysplasia of the hip.

BACKGROUND: Total hip replacement (THR) for Crowe type IV developmental dysplasia of the hip (DDH) is still challenging due to specific joint deformities and the high incidence of post-operative complications. OBJECTIVE: This study aimed to evaluate the clinical effect of trochanteric slide osteotomy (TSO) combined with a cementless femoral conical stem in THR for the treatment of Crowe type IV DDH. METHODS: Thirty-one total hip replacements (26 patients) with Crowe type IV DDH were performed using TSO combined with a cementless femoral conical stem. Surgical outcomes were evaluated using leg length discrepancy (LLD), Harris hip score, and post-operative complications. RESULTS: The average pre-operative LLD was 51 mm (range 46-58 mm), decreasing to an average of 10 mm (range 8-12 mm) post-operatively. As a result, the post-operative incidence of the Trendelenburg sign significantly decreased compared with the pre-operative incidence (P< 0.05). Bony union was identified in 26 hips (83.9%), fibrous union in four (12.9%), and non-union in one (3.2%). No acetabular or femoral component loosening, dislocation, or deep infection around the component was found in any of the patients during the follow-up period (27 to 39 months). The average Harris hip score improved from 63.0 ± 3.0 (range 58-69) to 93.3 ± 2.0 (range 91-96). CONCLUSION: TSO combined with a cementless conical stem in THR is an appropriate option for patients with high congenital hip dislocation.

Performance evaluation and clinical validation of optimized nucleotide MALDI-TOF-MS for mycobacterial identification.

Objective: To evaluate the performance and validate the diagnostic value of a nucleotide matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS) with the analysis process optimized in identification of mycobacterium species. Methods: The optimized analysis process was used for mycobacterial identification in the nucleic MALDI-TOF-MS. 108 samples were used for assessing the performance of nucleic MALDI-TOF-MS, including 25 reference standards, 37 clinical isolates, 37 BALF, and 9 plasmids. The BALF of 38 patients suspected of pulmonary mycobacterial infection was collected for validation. Clinical etiological diagnosis was used as the gold standard to evaluate the diagnostic value of nucleotide MALDI-TOF-MS. Results: The sensitivity, specificity, and accuracy of the nucleotide MALDI-TOF-MS in mycobacterial identification were 96.91%, 100% and 97.22%, respectively, and the limit of detection for mycobacterium tuberculosis (MTB) was 50 bacteria/mL. Among 38 patients suspected of pulmonary mycobacterial infection, 33 were diagnosed with pulmonary tuberculosis infection, and 5 with non-mycobacterial infection. In clinical validation, the positive rates of MALDI-TOF-MS, Xpert MTB/RIF, culture and AFS in BALF of patients diagnosed with tuberculosis infection were 72.7%, 63.6%, 54.5% and 27.3%, respectively. The sensitivity/specificity of MALDI-TOF-MS, Xpert, culture and AFS in diagnosing MTB were 72.7%/100%, 63.6%/100%, 54.5%/100%, 27.3%/100%, with the areas under the curve of 0.864, 0.818, 0.773, and 0.636, respectively. Conclusion: Optimized nucleotide MALDI-TOF-MS has satisfactory sensitivity, specificity and low LOD in the identification of mycobacteria, which may serve as a potential assay for mycobacterial identification.

Drill-and-prechop technique: modification of the drill-and-crack technique for mature cataracts.

BACKGROUND: There are some techniques for disassembly of hard nuclear. It is challenging in hard cataract surgery through microincision. The classic chop or prechop techniques often do not succeed,resulting in incomplete nuclear segmentation. The authors describe a new chop technique for removing hard nucleus cataracts in coaxial microincisional cataract surgery. METHODS: We create a deep hole (drill) in the central nucleus with the phaco tip and divide the nucleus (prechop) with the Nagahara chopper and the modified capsulorhexis forceps inside the hole. The chopper and the modified capsulorhexis forceps are spread apart laterally after they approach at the center of the nucleus, to create a complete fracture across the entire nucleus. Since January 2022, we have completed 27 eyes of 25 patients with hard nucleus cataract using this technique. RESULTS: Complete segmentation of the hard nuclear into two hemispheres was implemented with this drill and prechop technique in all cases. The effective phaco time and ultrasound energy decreased. No intraoperative complication such as iris injury, anterior capsule tears, zonulysis, or posterior capsule rupture with vitreous loss occurred during surgery. CONCLUSIONS: This technique simplifies the previous prechop techniques especially for hard nucleus in microincisional cataract surgery. The technique is efficient, safe and simple.

Acute toxicological study: EZY-1 with potent therapeutic effects of idiopathic pulmonary fibrosis and its mechanisms.

EZY-1 is an antifibrosis peptide purified from Eucheuma. In this study, we explored the acute toxicology of EZY-1 and the signaling pathways involved in its antifibrotic role. The mouse model of pulmonary fibrosis was induced by bleomycin. Pathological changes in lung tissue could be effectively inhibited by EZY-1. Acute toxicity and cell proliferation tests indicated that EZY-1 had no apparent toxicity to mice and cells. We identified proteins that could bind directly to EZY-1 in vitro on the basis of liquid chromatography-tandem mass spectrometry and bioinformatics analysis. EZY-1 inhibited pulmonary fibrosis via Wnt/ß-catenin, transforming growth factor (TGF)-ß/Smad, phosphoinositide 3-kinase/protein kinase B/ mammalian target of rapamycin, and activator of transcription 3 and Janus kinase 2/signal transducer pathways. A transwell micropore experiment showed that EZY-1 could inhibit cell migration and invasion. Western blotting analysis on transforming growth factor-ß1 (TGF-ß1)-induced A549 pulmonary fibrosis cell model suggested that EZY-1 could downregulate p-Smad3 (Ser423/Ser425), Smad4, ß-catenin, vimentin, and N-cadherin expression. ELISA showed that EZY-1 could inhibit collagen-I secretion. EZY-1 alleviated idiopathic pulmonary fibrosis (IPF) through regulating TGF-ß/Smad pathways, epithelial-mesenchymal transition processes, and collagen secretion, which provides a potential foundation for theoretical development of EZY-1 as a potential drug against IPF. PRACTICAL APPLICATIONS: We isolated a new 16-amino-acid peptide derived from the polypeptide extract of Eucheuma, named EZY-1. In vitro and in vivo assays show peptide EZY-1 is safe. The EZY-1 peptide alleviates IPF at lower doses than pirfenidone. EZY-1 alleviated idiopathic pulmonary fibrosis (IPF) through regulating TGF-ß/Smad pathways, epithelial-mesenchymal transition (EMT) processes, and collagen secretion, which provides a theoretical basis for the development of EZY-1 as a potential drug against IPF.

Differential gene expression analysis after DAPK1 knockout in hepatocellular carcinoma cells.

Background: The mechanism through which death-associated protein kinase 1 (DAPK1) causes hepatocellular carcinoma (HCC) progression remains unclear. In this study, we aimed to identify key proteins that were altered after DAPK1 knockout. Methods: Stable DAPK1 knockout HCC cell lines were established, then the differentially expressed genes (DEGs) of HCC were screened using the NetworkAnalyst database and enriched using the Metascape software. Protein-protein interaction networks (PPIs) were analyzed and visualized using the STRING database expansion. Results: In total, 732 differentially expressed genes were identified, including 415 upregulated genes and 317 downregulated genes. Through Cytoscape software scoring, 10 pivotal genes were found to be closely related to changes in DAPK1 expression; Kininogen-1 (KNG1), Complement C3 (C3), Metalloproteinase inhibitor 1 (TIMP1), and Alpha-2-HS-glycoprotein (AHSG) were the most strongly associated with DAPK1 expression changes. Moreover, western blot analysis results revealed that changes in the levels of proteins encoded by the four key genes after DAPK1 knockout were consistent with those seen in the database screening. Conclusions: These results provide a direction for further studies on the DAPK1 gene and on the mechanism through which DAPK1 leads to hepatocellular carcinoma development.

Glycosylation of Aromatic Glycosides by a Promiscuous Glycosyltransferase UGT71BD1 from Cistanche tubulosa.

Multiple-glycosylated glycosides are a major source of bioactive leads. However, most of the currently reported glycosyltransferases (GTases) mainly catalyze glycosylation of aglycones without sugar group substitution. GTases accepting diverse glycosides as substrates are rarely reported. In this article, a new GTase UGT71BD1 was identified from Cistanche tubulosa, a desert herb plant abundant with various phenylethanoid glycosides (PhGs). Interestingly, UGT71BD1 showed no activity toward the aglycone of PhGs. Instead, it could catalyze the further glycosylation of PhG compounds to produce new phenylethanoid multiglycosylated glycosides, including the natural rarely separated tetraglycoside PhGs. Extensive assays found the unprecedented substrate promiscuity of UGT71BD1 toward diverse glycosides including flavonoid glycosides, stilbene glycosides, and coumarin glycosides, performing further mono- or diglycosylation with efficient conversion rates. Using UGT71BD1, six multiglycosylated glycosides were prepared and structurally identified by NMR spectroscopy. These products showed enhanced pharmacological activities compared with the substrates. Docking, dynamic simulation, and mutagenesis studies identified key residues for UGT71BD1's activity and revealed that the sugar modules in glycosides play crucial roles in substrate recognition, thus partly illuminating the unusual substrate preference of UGT71BD1 toward diverse glycosides. UGT71BD1 could be a potential enzyme tool for glycosylation of diverse glycosides.

Proteomic Quantification of Lysine Acetylation and Succinylation Profile Alterations in Lung Adenocarcinomas of Non-Smoking Females.

Background: Epidemiological surveys in recent years have shown that the incidence of female lung adenocarcinomas has multiplied in both smoking and non-smoking populations. The cause of lung adenocarcinomas is still not clear. Protein post-translational modification is one of the causes of the development of cancer cells. Methods: Lung adenocarcinoma and paracancerous tissue samples were collected from female patients with no history of smoking. The differences in protein acetylation and succinylation of cancerous tissues and paracancerous tissues were analysed by LC-MS/MS with a TMT labelling method. We distinguished the differentially modified proteins and annotated these proteins in terms of Go annotation, protein domains, protein complex analysis and KEGG pathway analysis. Results: 972 acetylation sites on 556 proteins were identified, among which 875 Kac sites on 507 proteins were quantified, 2373 succinylation sites on 1205 proteins were identified, and 2205 Ksu sites on 1131 proteins were quantified. The acetylation levels of proteins, which contribute to DNA binding and gene expression regulation, were up-regulated. The proteins for which the succinylation levels were up-regulated were mainly involved in mitochondria carboxylic acid metabolism. We also identified simultaneously up-regulated or down-regulated acetylated and succinylated proteins and depicted their interaction network. Conclusion: This study provides insight into lung adenocarcinomas acetylation and succinylation profile alterations in carcinoma pathogenesis and provides a potential therapeutic target for lung adenocarcinomas.

Discoidin domain receptor 2 activation of p38 mitogen-activated protein kinase as an important pathway for osteonectin-regulating osteoblast mineralization.

OBJECTIVE: The present study aimed to determine the role of the discoidin domain receptor 2 (DDR2) in the osteonectin (ON) regulation of osteoblast mineralization through the activation of p38 mitogen-activated protein kinase (MAPK). METHODS: Four groups were established: the ON group, the inhibitor group, the Ddr2-small interfering ribonucleic acid (siRNA) group, and the control group. Osteoblasts from the parietal bones of neonatal Sprague-Dawley rats were isolated and cultured. In the ON group, 1 µg/mL ON was added to the osteoblasts. The gene expressions of collagen 1 (Col 1) and Ddr2 were detected using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In the inhibitor group, the osteoblasts were added to WRG-28 (a specific DDR2 inhibitor), and in the Ddr2-siRNA group, the osteoblasts were transfected with Ddr2-siRNA. The gene and protein expressions of DDR2, bone sialoprotein, osteocalcin, osteopontin, and p38 MAPK were determined using RT-qPCR and western blot analysis. Alizarin red staining and transmission electron microscopy were used to detect mineralization. RESULTS: The results showed that ON enhanced the osteoblast Col 1 and Ddr2 gene expressions, while the use of a Ddr2-siRNA/DDR2-blocker decreased the OPN, BSP, OCN, and P38 gene and protein expressions and reduced osteoblast cellular activity and mineralized nodules. CONCLUSION: The present study demonstrated that DDR2 activation of p38 MAPK is an important approach to ON-regulating osteoblast mineralization.

Programmable Engineering of Sunlight-Fueled, Full-Wavelength-Tunable, and Chirality-Invertible Helical Superstructures.

Dynamic control of motion at the molecular level is a core issue in promoting the bottom-up programmable modulation of sophisticated self-organized superstructures. Self-assembled artificial nanoarchitectures through subtle noncovalent interactions are indispensable for diverse applications. Here, the active solar renewable energy is used to harness cholesteric liquid crystal (CLC) superstructure devices via delicate control of the dynamic equilibrium between the concentrations of molecular motor molecules with opposite handedness. Thus, the spectral position and handedness of a photonic superstructure can be tuned continuously, bidirectionally, and reversibly within the entire working spectrum (from near-ultraviolet to the thermal infrared region, over 2 µm). With these unique horizons, three advanced photoresponsive chiroptical devices, namely, a mirrorless laser, an optical vortex generator, and an encrypted contactless photorewritable board, are successfully demonstrated. The sunlight-fueled chirality inversion prompts facile switching of functionalities, such as free-space optical communication, stereoscopic display technology, and spin-to-orbital angular momentum conversion. Motor-based chiroptic devices with dynamic and versatility controllability, fast response, ecofriendly characteristics, stability, and high efficiency have potential to replace the traditional elements with static functions. The inexhaustible natural power provides a promising means for outdoor-use optics and nanophotonics.

Control of Large-Area Orderliness of a 2D Supramolecular Chiral Microstructure by a 1D Interference Field.

Self-organized periodic micro/nanostructures caused by stimulus-responsive structural deformation often occur in anisotropic self-assembled supramolecular systems (e.g., liquid crystal systems). However, the long-range orderliness of these structures is often beyond control. In this article, we first demonstrate that a large-area disordered two-dimensional (2D) microgrid chiral structure appears in the cholesteric liquid crystal (CLC) reactive mixture because of the photopolymerization-induced Helfrich deformation effect under exposure to the single UV-laser beam. The result is attributed to the impact of an internal longitudinal strain, which is caused by the pitch contraction of the CLC-monomer region through the continuing compression of the thickening CLC polymer layer adhered on the illuminated substrate of the sample during photopolymerization. The experimental results further show that a one-dimensional (1D) UV-laser interference field can be used to effectively control the postformed 2D microgrid structure to arrange in an orderly manner throughout the large exposed area (an order of centimeter). The optimum ability for controlling the orderliness of the microgrid structure can be achieved if the spacing width of the interference field approximates the periodicity of the postformed 2D microgrids. Several factors, such as the pitch of the CLC mixture and the included angle and intensity of the two interfering laser beams, which influence the orderliness and properties of the 2D microgrid structure, are explored in this study. The result of this research opens a new page to improve the applicability of the Helfrich deformation phenomenon and further provides a reference platform for manipulating, modifying, and even tailoring periodic micro/nanostructures in self-organized supramolecular soft-matter systems for application in advanced optics/photonics.

Molecular cloning and biochemical characterization of a new coumarin glycosyltransferase CtUGT1 from Cistanche tubulosa.

UDP-glycosyltransferases (UGTs) are an important and functionally diverse family of enzymes involved in secondary metabolite biosynthesis. Coumarin is one of the most common skeletons of natural products with candidate pharmacological activities. However, to date, many reported GTs from plants mainly recognized flavonoids as sugar acceptors. Only limited GTs could catalyze the glycosylation of coumarins. In this study, a new UGT was cloned from Cistanche tubulosa, a valuable traditional tonic Chinese herb, which is abundant with diverse glycosides such as phenylethanoid glycosides, lignan glycosides, and iridoid glycosides. Sequence alignment and phylogenetic analysis showed that CtUGT1 is phylogenetically distant from most of the reported flavonoid UGTs and adjacent to phenylpropanoid UGTs. Extensive in vitro enzyme assays found that although CtUGT1 was not involved in the biosynthesis of bioactive glycosides in C. tubulosa, it could catalyze the glucosylation of coumarins umbelliferone 1, esculetine 2, and hymecromone 3 in considerable yield. The glycosylated products were identified by comparison with the reference standards or NMR spectroscopy, and the results indicated that CtUGT1 can regiospecifically catalyze the glucosylation of hydroxyl coumarins at the C7-OH position. The key residues that determined CtUGT1's activity were further discussed based on homology modeling and molecular docking analyses. Combined with site-directed mutagenesis results, it was found that H19 played an irreplaceable role as the crucial catalysis basis. CtUGT1 could be used in the enzymatic preparation of bioactive coumarin glycosides.