Phosphorylation-dependent deubiquitinase OTUD3 regulates YY1 stability and promotes colorectal cancer progression.

Yin Yang 1 (YY1) is a key transcription factor that has been implicated in the development of several malignancies. The stability of YY1 is regulated by the ubiquitin-proteasome system. The role of deubiquitinases (DUBs) and their impact on YY1 remain to be fully elucidated. In this study, we screened for ubiquitin-specific proteases that interact with YY1, and identified OTUD3 as a DUB for YY1. Over-expressed OTUD3 inhibited YY1 degradation, thereby increasing YY1 protein levels, whereas OTUD3 knockdown or knockout promoted YY1 degradation, thereby decreasing the proliferation of colorectal cancer (CRC). Furthermore, PLK1 mediates OTUD3 S326 phosphorylation, which further enhances OTUD3 binding and deubiquitination of YY1. In CRC tissues, elevated the expression level of OTUD3 and YY1 were significantly associated with poor prognostic outcomes. These findings suggest that the OTUD3-YY1 pathway has therapeutic potential in CRC, and OTUD3 plays a critical role in regulating YY1.

Facile fabrication of carbon nanotube hollow microspheres as a fiber coating for ultrasensitive solid-phase microextraction of phthalic acid esters in tea beverages.

The efficient extraction of phthalic acid esters (PAEs) is challenging due to their extremely low concentration, complicated matrices and hydrophilicity. Herein, hollow microspheres, as an ideal coating, possess significant potential for solid-phase microextraction (SPME) due to their fascinating properties. In this study, multiwalled carbon nanotube hollow microspheres (MWCNT-HMs) were utilized as a fiber coating for the SPME of PAEs from tea beverages. MWCNT-HMs were obtained by dissolving the polystyrene (PS) cores with organic solvents. Interestingly, MWCNT-HMs well maintain the morphology of the MWCNTs@PS precursors. The layer-by-layer (LBL) assembly of MWCNTs on PS microsphere templates was achieved through electrostatic interactions. Six PAEs, di-ethyl phthalate (DEP), di-iso-butyl phthalate (DIBP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP) and di-n-octyl phthalate (DOP), were selected as target analytes for assessing the efficiency of the coating for SPME. The stirring rate, sample solution pH and extraction time were optimized by using the Box-Behnken design. Under optimal working conditions, the proposed MWCNT-HMs/SPME was coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) to achieve high enrichment factors (118-2137), wide linearity (0.0004-10 µg L-1), low limits of detection (0.00011-0.0026 µg L-1) and acceptable recovery (80.2-108.5%) for the detection of PAEs. Therefore, the MWCNT-HM coated fibers are promising alternatives in the SPME method for the sensitive detection of PAEs at trace levels in tea beverages.

Sulfonated, oxidized pectin-based double crosslinked bioprosthetic valve leaflets for synergistically enhancing hemocompatibility and cytocompatibility and reducing calcification.

Clinically frequently-used glutaraldehyde (GA)-crosslinked bioprosthetic valve leaflets (BVLs) are still curbed by acute thrombosis, malignant immunoreaction, calcification, and poor durability. In this study, an anticoagulant heparin-like biomacromolecule, sulfonated, oxidized pectin (SAP) with a dialdehyde structure was first obtained by modifying citrus pectin with sulfonation of 3-amino-1-propane sulfonic acid and then oxidating with periodate. Notably, a novel crosslinking approach was established by doubly crosslinking BVLs with SAP and the nature-derived crosslinking agent quercetin (Que), which play a synergistic role in both crosslinking and bioactivity. The double crosslinked BVLs also presented enhanced mechanical properties and enzymatic degradation resistance owing to the double crosslinking networks formed via CN bonds and hydrogen bonds, respectively, and good HUVEC-cytocompatibility. The in vitro and ex vivo assay manifested that the double-crosslinked BVLs had excellent anticoagulant and antithrombotic properties, owing to the introduction of SAP. The subcutaneous implantation also demonstrated that the obtained BVLs showed a reduced inflammatory response and great resistance to calcification, which is attributed to quercetin with multiple physiological activities and depletion of aldehyde groups by hydroxyl aldehyde reaction. With excellent stability, hemocompatibility, anti-inflammatory, anti-calcification, and pro-endothelialization properties, the obtained double-crosslinked BVLs, SAP + Que-PP, would have great potential to substitute the current clinical GA-crosslinked BVLs.

Well-designed two-fold crosslinked biological valve leaflets with heparin-loaded hydrogel coating for enhancing anticoagulation, endothelialization, and anticalcification.

Commercial biological valve leaflets (BVLs) crosslinked with glutaraldehyde (GA) are at risk of accelerating damage and even failure, owing to the high cell toxicity of GA, acute thrombosis, and calcification in clinical applications. In this study, a novel joint strategy of double crosslinking agents (dialdehyde pectin (AP) and carbodiimide) and heparin-loaded hydrogel coating was developed, endowing BVLs with excellent mechanical properties and multiple performances. Herein, AP played two essential roles, the crosslinking agent and the main component of the hydrogel coating. Both experimental and theoretical results indicated that the mechanical properties and stability of double-crosslinked BVLs were comparable to those of GA, and heparin loaded in hydrogel coating could improve the hemocompatibility of AP + EDC/NHS-PP. Further, cytocompatibility and in vivo tests showed that compared with GA-PP, AP + EDC/NHS + CS + Hep-PP has exhibited good endothelialization ability, mild immune response and anti-calcification performance and therefore prompts it to be an extremely valuable candidate for more durable and multifunctional BVLs.

Dialdehyde pectin-crosslinked and hirudin-loaded decellularized porcine pericardium with improved matrix stability, enhanced anti-calcification and anticoagulant for bioprosthetic heart valves.

To conveniently and effectively cure heart valve diseases or defects, combined with transcatheter valve technology, bioprosthetic heart valves (BHVs) originated from the decellularized porcine pericardium (D-PP) have been broadly used in clinics. Unfortunately, most clinically available BHVs crosslinked with glutaraldehyde (GA) were challenged in their long-term tolerance, degenerative structural changes, and even failure, owing to the synergistic impact of multitudinous elements (cytotoxicity, calcification, immune responses, etc.). In this work, dialdehyde pectin (AP) was prepared by oxidizing the o-dihydroxy of pectin with sodium periodate. Hereafter, the AP-fixed PP model was obtained by crosslinking D-PP with AP with high aldehyde content (6.85 mmol g-1), for acquiring excellent mechanical properties and outstanding biocompatibility. To further improve the hemocompatibility of the AP-fixed PP, a natural and specific inhibitor of thrombin (hirudin) was introduced to achieve surface modification of the AP-fixed PP. The feasibility of crosslinking and functionalizing AP-fixed PP, which was a potential leaflet material of BHVs, was exhaustively and systematically evaluated. In vitro studies found that hirudin-loaded and AP-fixed PP (AP + Hirudin-PP) had synchronously achieved effective fixation of collagen, highly effective anticoagulation, and good HUVECs-cytocompatibility. In vivo results revealed that the AP + Hirudin-PP specimens recruited the minimum immune cells in the implantation experiment, and also presented an excellent anti-calcification effect. Overall, AP + Hirudin-PP was endowed with competitive collagen stability (compared with GA-fixed PP), excellent hemocompatibility, good HUVECs-cytocompatibility, low immunogenicity and outstanding anti-calcification, suggesting that AP + Hirudin-PP might be a promising alternative to GA-fixed PP and exhibited a bright prospect in the clinical applications of BHVs.

Natural alkaloid and polyphenol compounds targeting lipid metabolism: Treatment implications in metabolic diseases.

Once the balance between lipid anabolism and catabolism is broken, metabolic disorder will occur in the organism and finally lead to metabolic diseases, such as nonalcoholic fatty liver disease (NAFLD), obesity and cancer. No established therapeutic regimens for treating NAFLD and obesity exist yet. Many natural compounds are extracted from botany, fungi and marine organisms. Importantly, natural compounds are major sources of innovative medicine. In this review, we first elucidate the important roles of lipid metabolism in NAFLD, obesity and cancer. Next, we summarize the action mechanisms of natural compounds including alkaloid, polyphenol targeting lipid metabolism. Therefore, manipulating lipid metabolism to reduce fatty acid availability may be the starting point for improving or even curing lipid metabolism-related diseases. Alkaloid and polyphenol are promising candidates for metabolic diseases to ameliorate lipid metabolism abnormalities.

[Research progress on chemical compounds and pharmacological effects of Caesalpinia].

Consult literature, the chemical composition of the type of system Caesalpinia plants were summarized and discussed in detail its pharmacological effects. The genus contains major chemical components of high isoflavones, chalcones and diterpenoids, pharmacological effects inhibit melanin production, anti-inflammatory, antioxidant, antibacterial, immune regulation, and further research in this genus offer reference.

[Simultaneous determination of quercitrin, phloridzin and 3-hydroxyl phloridzin in leaves of Malus halliana by ultrasound-assisted ionic liquid-reversed phase liquid chromatography].

To establish a method for the simultaneous determination of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of Malus halliana by ultrasonic-assisted ionic liquid coupled with RP-HPLC. An Agilent TC-C18 (4.6 mm×250 mm, 5 µm) column was used, with the mobile phase of acetonitrile and 1% phosphoric acid-water (20∶80) by gradient elution at the detection wavelength of 270 nm. The flow rate was 0.8 mL•min⁻¹, and chromatographic column temperature was controlled at the room temperature. Under the optimized conditions, the linear ranges for phloridzin, 3-hydroxy phloridzin and quercitrin were 0.9-112.5 µg (r = 0.999 6), 0.093 2-11.65 µg (r = 0.999 1) and 0.097 2-12.15 µg (r = 0.999 8), respectively. The average recoveries of the three constituents were 99.35%, 98.80% and 98.19%, respectively. The method was environmental friendly, rapid, accurate and highly reproducible, and so suitable for the quantitative analysis of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of M. halliana.

[Effect of heating treatment on stability of two coumarins in Angelica dahurica and activity of tyrosinase].

To study the heating treatment of Angelica dahurica under different temperature and time conditions on the stability of coumarins and tyrosinase activity. HPLC method was used to determine the contents of imperatorin and isoimperatorin, and tyrosinase activity was assayed by measuring the oxidation rate of L-DOPA in vitro. After heated, the contents of imperatorin increased. Expect for being heated at 90 ℃ for 2 h, the content of isoimperatorin was higher than crude one. Before and after being heated, A. dahurica showed an activating effect on tyrosinase. In the same temperature and time conditions, the activation rate increased with the rise of concentration of tyrosinase extracts. Heating process for A. dahurica could change the contents of imperatorin and isoimperatorin, mainly increasing their concentrations.