The Self-Specific Activation Receptor SLAM Family Is Critical for NK Cell Education.

NK cell education, a term describing a process for NK cell acquisition of functional competence, is primarily achieved by self-MHC-I-specific inhibitory receptors. In this study, we have demonstrated that SLAM family receptors (SFRs) redundantly expressed on hematopoietic cells function as self-specific activation receptors critical for NK cell education. To overcome gene redundancy, we generated mice simultaneously lacking seven SFRs, revealing that NK-cell-mediated rejection of semi-allogeneic hematopoietic cells largely depended on the presence of SFRs on target cells. This stimulatory effect was determined by the presence of SFR-coupled adaptors; however, SFR-deficient mice displayed enhanced reactivity to hematopoietic cells. These findings demonstrate that SFRs endow NK cells with an ability to kill hematopoietic cells during the effector phase; however, the sustained engagement of SFRs can desensitize NK cell responses during an education process. Therefore, self-specific activating ligands may be "tolerogens" for NK cells, akin to self-antigens that induce T cell tolerance.

Hierarchical-Bioinspired MOFs Enhanced Electromagnetic Wave Absorption.

Proteins exhibit complex and diverse multi-dimensional structures, along with a wide range of functional groups capable of binding metal ions. By harnessing the unique characteristics of proteins, it is possible to enhance the synthesis of metal-organic frameworks (MOFs) and modify their morphology. Here, the utilization of biomineralized bovine serum albumin (BSA) protein as a template for synthesizing Mil-100 with superior microwave absorption (MA) properties is investigated. The multi-dimensional structure and abundant functional groups of biomineralized BSA protein make it an ideal candidate for guiding the synthesis of Mil-100 with intricate network structures. The BSA@Mil-100 synthesized using this method exhibits exceptional uniformity and monodispersity of nanocrystals. The findings suggest that the BSA protein template significantly influences the regulation of nanocrystal and microstructure formation of Mil-100, resulting in a highly uniform and monodisperse structure. Notably, the synthesized 2-BSA@Mil-100 demonstrates a high reflection loss value of -58 dB at 8.85 GHz, along with a maximum effective absorption bandwidth value of 6.79 GHz, spanning from 6.01 to 12.8 GHz. Overall, this study highlights the potential of utilizing BSA protein as a template for MOF synthesis, offering an effective strategy for the design and development of high-performance MA materials.

Remnant cholesterol and the risk of aortic valve calcium progression: insights from the MESA study.

BACKGROUND: Remnant cholesterol (RC) is implicated in the risk of cardiovascular disease. However, comprehensive population-based studies elucidating its association with aortic valve calcium (AVC) progression are limited, rendering its precise role in AVC ambiguous. METHODS: From the Multi-Ethnic Study of Atherosclerosis database, we included 5597 individuals (61.8 ± 10.1 years and 47.5% men) without atherosclerotic cardiovascular disease at baseline for analysis. RC was calculated as total cholesterol minus high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), as estimated by the Martin/Hopkins equation. Using the adjusted Cox regression analyses, we examined the relationships between RC levels and AVC progression. Furthermore, we conducted discordance analyses to evaluate the relative AVC risk in RC versus LDL-C discordant/concordant groups. RESULTS: During a median follow-up of 2.4 ± 0.9 years, 568 (10.1%) participants exhibited AVC progression. After adjusting for traditional cardiovascular risk factors, the HRs (95% CIs) for AVC progression comparing the second, third, and fourth quartiles of RC levels with the first quartile were 1.195 (0.925-1.545), 1.322 (1.028-1.701) and 1.546 (1.188-2.012), respectively. Notably, the discordant high RC/low LDL-C group demonstrated a significantly elevated risk of AVC progression compared to the concordant low RC/LDL-C group based on their medians (HR, 1.528 [95% CI 1.201-1.943]). This pattern persisted when clinical LDL-C threshold was set at 100 and 130 mg/dL. The association was consistently observed across various sensitivity analyses. CONCLUSIONS: In atherosclerotic cardiovascular disease-free individuals, elevated RC is identified as a residual risk for AVC progression, independent of traditional cardiovascular risk factors. The causal relationship of RC to AVC and the potential for targeted RC reduction in primary prevention require deeper exploration.

A new preparation method of covalent annular nanodiscs based on MTGase.

The preservation of the native conformation and functionality of membrane proteins has posed considerable challenges. While detergents and liposome reconstitution have been traditional approaches, nanodiscs (NDs) offer a promising solution by embedding membrane proteins in phospholipids encircled by an amphipathic helical protein MSP belt. Nevertheless, a drawback of commonly used NDs is their limited homogeneity and stability. In this study, we present a novel approach to construct covalent annular nanodiscs (cNDs) by leveraging microbial transglutaminase (MTGase) to catalyze isopeptide bond formation between the side chains of terminal amino acids, specifically Lysine (K) and Glutamine (Q). This methodology significantly enhances the homogeneity and stability of NDs. Characterization of cNDs and the assembly of membrane proteins within them validate the successful reconstitution of membrane proteins with improved homogeneity and stability. Our findings suggest that cNDs represent a more suitable tool for investigating interactions between membrane proteins and lipids, as well as for analyzing membrane protein structures.

Chemoproteomic Profiling of Erastin-Interacting Proteins.

Ferroptosis is an iron-related cell death caused by irregular lipid peroxidation that has been implicated with a variety of disease. Erastin is a canonical ferroptosis inducer that is known to function by inhibiting system Xc- and cystine transport; however, the global interactome of erastin in cells remains unexplored. In this work, we employed a quantitative chemoproteomic approach to profile direct interacting proteins of erastin in living cells using a multifunctional photo-cross-linking probe. A number of novel erastin-interacting proteins were identified, including a serine hydrolase, ABHD6, whose overexpression showed a potentiating impact on ferroptosis. Further biochemical experiments revealed that erastin can allosterically activate ABHD6's activity to produce more arachidonic acids and elevate the level of lipid reactive oxygen species. Collectively, our work provided a global portrait of erastin-interacting proteins and discovered ABHD6 as a new ferroptosis regulator.

Fabrication of Uniform Anionic Polymeric Nanoplatelets as Building Blocks for Constructing Conductive Hydrogels with Enhancing Conductive and Mechanical Properties.

Conductive hydrogels play a crucial role in advancing technologies like implantable bioelectronics and wearable electronic devices, owing to their favorable conductivity and appropriate mechanical properties. Here, a novel bottom-up approach is reported for crafting conductive nanocomposite hydrogels to achieve enhancing conductive and mechanical properties. In this approach, new poly(ɛ-caprolactone)-based block copolymers with sulfonic groups are first synthesized and self-assembled into uniform polyanionic nanoplatelets. Subsequently, these negatively charged nanoplatelets, with sulfonic groups on the surface, are employed as nanoadditives for the polymerization of 3,4-ethylenedioxythiophene (EDOT), resulting in poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/nanoplatelet complex with 3.8 times enhanced electrical conductivity compared with their counterparts prepared using block copolymers (BCPs). Blending the (PEDOT:PSS)/nanoplatelet complex with calcium alginate, nanocomposite hydrogels are successfully prepared. In comparison with hydrogels with (PEDOT:PSS)/BCP complexes prepared by a top-down method, the nanocomposite hydrogels are found to show twice as strong mechanical strength and 1.6 times higher conductivity. This work provides valuable insights into the bottom-up construction of conductive hydrogels for bioelectronics using well-controlled polymeric nanoplatelets.

Unraveling cadmium-driven liver inflammation with a focus on arachidonic acid metabolites and TLR4/ IκBα /NF-κB pathway.

Epidemiological studies have demonstrated exposure to cadmium ion (Cd2+) is significantly associated with the incidence and aggravation of nonalcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH). Cd2+ exposure could alter lipid metabolism, and changed lipid metabolites are significantly associated with NASH. Arachidonic acid (ArA) is an omega-6 polyunsaturated fatty acid. Promotion of ArA synthesis and profile changes by Cd2+ exposure potentially to cause NAFLD. ArA metabolism pathway has been identified to enrich in Cd2+ exposure-facilitated NASH. ArA could be generation an impressive metabolic profile through mainly three pathways, including Cyclooxygenases (COX), Lipoxygenases (LOX) and Cytochrome P450 (CYP450) pathway. However, the functions of these metabolites and underlying mechanism in hepatic inflammation are still not clear. In present study, by integrative transcriptomics and metabolomics analysis, we identified that the fatty acid metabolic process and the pro-inflammatory NF-κB signaling pathway were enriched in Cd2+-regulated differentially expressed genes (DEGs) and Cd2+-altered differential metabolites, such as, fatty acid biosynthesis, degradation, and ArA metabolism. The metabolites levels of LOX pathway products 5-HETE and leukotriene C4 (LTC4), and COX catalytic product prostaglandin D2 (PGD2) were significantly elevated in Cd2+ exposed mouse livers. 5-HETE, LTC4, and PGD2 were significantly positive correlated with NF-κB signaling. In addition, the synthase of 20-Hydroxyeicosatetraenoic acid (20-HETE), CYP450 gene 4 family (CYP4A32), was also involved in NF-κB signaling network. Results from both in vitro and in vivo proved that Cd2+ exposure increased ArA metabolite to PGD2 and 20-HETE, and upregulated the mRNA level of their catalytic enzyme PGDS and CYP4A32. Cd2+-induced ArA metabolite to PGD2 and 20-HETE promoted activation of TLR4/IκBα/NF-κB signaling and pro-inflammatory of hepatocytes. Our study explores novel molecular mechanism of Cd2+ exposure-aggravated liver diseases and provides potential novel targets for in hepatic inflammatory treatments and prevention.

Cadmium promoted LPS-induced inflammation through TLR4/IκBα/NFκ-B signaling by increasing ROS-mediated incomplete autophagy.

Cadmium (Cd) exposure is considered as non-infectious stressor to human and animal health. Recent studies suggest that the immunotoxicity of low dose Cd is not directly apparent, but disrupts the immune responses when infected with some bacteria or virus. But how Cd alters the adaptive immunity organ and cells remains unclear. In this study, we applied lipopolysaccharide (LPS, infectious stressor) to induced inflammation in spleen tissues and T cells, and investigated the effects after Cd exposure and the underlying mechanism. Cd exposure promoted LPS-induced the expressions of the inflammatory factors, induced abnormal initiation of autophagy, but blocked autophagic flux. The effects Cd exposure under LPS activation were reversed by the autophagy promoter Rapamycin. Under LPS activation conditions, Cd also induced oxidative stress by increasing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and reducing total antioxidant capacity (T-AOC) activity. The increased superoxide dismutase (SOD) activity after Cd exposure might be a negative feedback or passive adaptive regulation of oxidative stress. Cd-increased autophagic flux inhibition and TNF-α expression were reversed by ROS scavenger α-tocopherol (TCP). Furthermore, under LPS activation condition, Cd promoted activation of toll-like receptor 4 (TLR4)/IκBα/NFκ-B signaling pathway and increased TLR4 protein stability, which were abolished by the pretreatment of Rapamycin. The present study confirmed that, by increasing ROS-mediated inhibiting autophagic degradation of TLR4, Cd promoted LPS-induced inflammation in spleen T cells. This study identified the mechanism of autophagy in Cd-aggravated immunotoxicity under infectious stress, which could arouse public attention to synergistic toxicity of Cd and bacterial or virus infection.

Boosting SARS-CoV-2 Enrichment with Ultrasmall Immunomagnetic Beads Featuring Superior Magnetic Moment.

The isolation and enrichment efficiency of SARS-CoV-2 virus in complex biological environments is often relatively low, presenting challenges in direct detection and an increased risk of false negatives, particularly during the early stages of infection. To address this issue, we have developed a novel approach using ultrasmall magnetosome-like nanoparticles (≤10 nm) synthesized via biomimetic mineralization of the Mms6 protein derived from magnetotactic bacteria. These nanoparticles are surface-functionalized with hydrophilic carboxylated polyethylene glycol (mPEG2000-COOH) to enhance water solubility and monodispersity. Subsequently, they are coupled with antibodies targeting the receptor-binding domain (RBD) of the virus. The resulting magnetosome-like immunomagnetic beads (Mal-IMBs) exhibit high magnetic responsiveness comparable to commercial magnetic beads, with a saturation magnetization of 90.6 emu/g. Moreover, their smaller particle size provides a significant advantage by offering a higher specific surface area, allowing for a greater number of RBD single-chain fragment variable (RBD-scFv) antibodies to be coupled, thereby enhancing immune capture ability and efficiency. To validate the practicality of Mal-IMBs, we evaluated their performance in recognizing the RBD antigens, achieving a maximum capture ability of 83 µg/mg per unit mass. Furthermore, we demonstrated the binding capability of Mal-IMBs to SARS-CoV-2 pseudovirus using fluorescence microscopy. The Mal-IMBs effectively enriched the pseudovirus at a low copy concentration of 70 copies/mL. Overall, the small Mal-IMB exhibited excellent magnetic responsiveness and binding efficiency. By employing a multisite virus binding mechanism, it significantly improves the enrichment and separation of SARS-CoV-2 in complex environments, facilitating rapid detection of COVID-19 and contributing to effective measures against its spread.

Identification evidence unraveled by strict proteomics rules toward forensic samples.

Snake venom is a complex mixture of proteins and peptides secreted by venomous snakes from their poison glands. Although proteomics for snake venom composition, interspecific differences, and developmental evolution has been developed for a decade, current diagnosis or identification techniques of snake venom in clinical intoxication and forensic science applications are mainly dependent on morphological and immunoassay. It could be expected that the proteomics techniques directly offer great help. This work applied a bottom-up proteomics method to identify proteins' types and species attribution in suspected snake venom samples using ultrahigh-performance liquid chromatography-quadrupole-electrostatic field Orbitrap tandem mass spectrometric technique, and cytotoxicity assay was amended to provide a direct evidence of toxicity. Toward the suspicious samples seized in the security control, sample pretreatment (in-sol and in-gel digestion) and data acquisition (nontargeted and targeted screening) modes complemented and validated each other. We have implemented two consequent approaches in identifying the species source of proteins in the samples via the points of venom proteomics and strict forensic identification. First, we completed a workflow consisting of a proteomics database match toward an entire SWISS-PROT (date 2018-11-22) database and a result-directed specific taxonomy database. The latter was a helpful hint to compare master protein kinds and reveal the insufficiency of specific venom proteomics characterization rules. Second, we suggested strict rules for protein identification to meet the requirements of forensic science on improved identification correctness, that is, (1) peptide spectrum matches confidence, peptide confidence, and protein confidence were both high (with the false-discovery ratio less than 1%); (2) the number of unique peptides was more than or equal to two in one protein, and (3) within unique peptides, which at least 75% of the ∆m/z of the matched y and b ions were less than 5 ppm. We identified these samples as cobra venom containing 10 highly abundant proteins (P00597, P82463, P60770, Q9YGI4, P62375, P49123, P80245, P60302, P01442, and P60304) from two snake venom protein families (acid phospholipase A2 and three-finger toxins), and the most abundant proteins were cytotoxins.

Masked face recognition with convolutional visual self-attention network.

With the global outbreak of COVID-19, wearing face masks has been actively introduced as an effective public measure to reduce the risk of virus infection. This measure leads to the failure of face recognition in many cases. Therefore, it is very necessary to improve the recognition performance of masked face recognition (MFR). Inspired by the successful application of self-attention in computer vision, we propose a Convolutional Visual Self-Attention Network (CVSAN), which uses self-attention to augment the convolution operator. Specifically, this is achieved by connecting a convolutional feature map, which enforces local features, to a self-attention feature map that is capable of modeling long-range dependencies. Since there is currently no publicly available large-scale masked face data, we generate a Masked VGGFace2 dataset based on the face detection algorithm to train the CVSAN model. Experiments show that the CVSAN algorithm significantly improves the performance of MFR compared to other algorithms.

Enzymatic Electrosynthesis of Glycine from CO2 and NH3.

Enzymatic electrosynthesis has gained more and more interest as an emerging green synthesis platform, particularly for the fixation of CO2 . However, the simultaneous utilization of CO2 and a nitrogenous molecule for the enzymatic electrosynthesis of value-added products has never been reported. In this study, we constructed an in vitro multienzymatic cascade based on the reductive glycine pathway and demonstrated an enzymatic electrocatalytic system that allowed the simultaneous conversion of CO2 and NH3 as the sole carbon and nitrogen sources to synthesize glycine. Through effective coupling and the optimization of electrochemical cofactor regeneration and the multienzymatic cascade reaction, 0.81 mM glycine was yielded with a highest reaction rate of 8.69 mg L-1 h-1 and faradaic efficiency of 96.8 %. These results imply a promising alternative for enzymatic CO2 electroreduction and expand its products to nitrogenous chemicals.

In Vitro Evaluation of DNA Damage Effect Markers toward Five Nitrogen Mustards Based on Liquid Chromatography-Tandem Mass Spectrometry.

Endogenous DNA lesions frequently occur due to internal effects such as oxidative stress, inflammation, endogenous alkylation, and epigenetic modifications. However, exposure to chemical toxicants from the environment, diet, or drugs can also induce significant endogenous DNA damage. The quantification of endogenous DNA damage effect markers might reflect the actual DNA damage level of chemical toxicants. Herein, we report a liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ MS/MS) method for simultaneous determination of eight representative endogenous DNA damage biomarkers, including five endogenous DNA damage effect markers (oxidative damage, 8-oxo-dG; lipid peroxidation, εdA and N2-Et-dG; inflammation, 5-Cl-dC; and endogenous alkylation, O6-Me-dG), and three epigenetic modifications (5-m-dC, 5-hm-dC, and N6-Me-dA). The method validation was performed, and the linear range was 0.05 pg to 2 ng (on-column), the limit of detection was 0.02 pg (on-column), and the precision, accuracy, matrix effect, and recovery were all between 85 and 115%. We then applied this method to evaluate endogenous DNA damage to human embryonic lung fibroblast cells exposed to five nitrogen mustards [NMs, i.e., HN1, HN2, HN3, chlorambucil (CB), and cyclophosphamide (CTX)], where curcumin exposure was used as a control due to its inability to induce the formation of endogenous DNA adducts. The amounts of eight DNA adducts in the low-, middle-, and high-concentration exposure groups of five NMs were almost all significantly different from those in the blank group (P < 0.05). We obtained a positive correlation between the contents of eight DNA damage biomarkers and the inhibition dose of five NMs, except for N2-Et-dG and 5-Cl-dC. Via further principal component analysis and partial least squares discriminant analysis, we clustered all NMs into three units with different cytotoxicity levels, that is, HN2 and HN1 (highly toxic), HN3 and CB (moderately toxic), and CTX (less toxic). Moreover, for the same concentration of HN1/2/3 exposure groups, as the cytotoxicity increased according to the order of HN3 < HN1 < HN2, the contents of 8-oxo-dG, 5-m-dC, 5-hm-dC, and N6-Me-dA increased, whereas the content of O6-Me-dG decreased. Therefore, the contents of these DNA damage effect markers were somewhat related to the cytotoxicity and concentration of NMs. We hope that this method will provide an alternative evaluation approach for the toxicological effects of NMs and the safety of the medication.

Thermal desorption bridged the gap between dielectric barrier discharge ionization and dried plasma spot samples for sensitive and rapid detection of fentanyl analogs in mass spectrometry.

The urgent threat of new psychoactive substances worldwide promotes rapid detection and identification demand for public security. Ambient ionization mass spectrometry (AIMS) has become mainstream among various detection techniques. Still, scant successful applications have been fulfilled toward dried blood spot (DBS) or plasma spot (DPS) as an easy-to-implement sampling format in AIMS. This work bridged the gap between dielectric barrier discharge ionization mass spectrometry (DBDI-MS) and DPS/DBS samples by thermal desorption (TD) assistance. It made the impossible mission of direct DBDI-MS measurement on DPS/DBS samples containing fentanyl analogs (FTNs) possible. Guided by finite element simulations and a customized three-dimensional printing interface, we constructed a semi-covered flat-TD surface for sufficient desorption and ionization of FTNs from DPS/DBS samples without any sample pretreatment or sample separation. We successfully quantified eight FTNs in DPS samples using deuterated fentanyl as internal standard by triple quadrupole tandem mass spectrometry (MS/MS) and proved its practical applicability in the fentanyl-exposed rat plasma samples. This DBDI-TD-MS method also fits well with DBS samples, and it only took 20 s to analyze each sample. Further, based on summarized fragmentation characteristics of twenty FTNs, we established a backbone alerting ion-guided screening rule for suspect screening of FTNs in DPS samples via quadrupole time-of-flight MS/MS and built a chemometric approach for convenient mutual verification of screening "unknown" artificial samples. We hope this ideal DBDI-TD-MS method finds its valuable role in national security, doping control, and public health for routine large-scale analysis or on-site detection.

Dual effects of bisphenol A on wound healing, involvement of estrogen receptor ß.

Bisphenol A (BPA) is a ubiquitous environmental pollutant that can specifically induce estrogen receptor ß (ERß) expression, and the latter plays a crucial role during wound healing. However, no study has investigated the association between BPA exposure and skin regeneration. This study aimed to explore the impacts of BPA on wound repair using mice models. C57BL/6 mice were administrated with BPA in two different ways during the process of wound healing-dietary intake (5 and 50 mg/kg) and wound application (1 and 100 nM). Mice primary fibroblasts were exposed to BPA to verify the role of BPA on the function of fibroblasts. We also applied BPA in diabetic mice to evaluate its therapy value. BPA showed dual effects on wound healing, which were dependent on the application routes. Dietary intake of BPA delayed wound healing by suppressing ovarian estrogen secretion, whereas wound application of BPA accelerated skin regeneration via up-regulating wound localized ERß expression. Highly expressed ERß enhanced the function of fibroblasts and promoted the transformation from fibroblasts to myofibroblasts. Impacts of BPA on wound healing were dismissed when ERß was blocked. Moreover, wound application of BPA significantly accelerated wound repair in diabetic mice, but has no significant adverse effect on ovarian hormones levels. The current study indicates that although BPA disrupts the function of the endocrine system when administrated by diet, local application of BPA on wounds shows a superior role in promoting wound repair, and this may provide a novel approach for the therapy of pathologic wound healing.

JMJD8 Functions as a Novel AKT1 Lysine Demethylase.

JMJD8 is a protein from the JMJD family that only has the JmjC domain. Studies on the function of JMJD8 indicate that JMJD8 is involved in signaling pathways, including AKT/NF-κB, and thus affects cell proliferation and development. Here, we reported the activity of JMJD8 as a non-histone demethylase. We investigated the demethylation of JMJD8 on trimethylated lysine of AKT1 in vivo and in vitro using trimethylated AKT1 short peptide and AKT1 protein, and we tracked the regulation of JMJD8 on AKT1 activity at the cellular level. The results showed that JMJD8, a mini lysine demethylase, altered AKT1 protein function via changing its degree of methylation.

Design of Low Bandgap CsPb1- x Snx I2 Br Perovskite Solar Cells with Excellent Phase Stability.

Novel all-inorganic Sn-Pb alloyed perovskites are developed aiming for low toxicity, low bandgap, and long-term stability. Among them, CsPb1- x Snx I2 Br is predicted as an ideal perovskite with favorable band gap, but previously is demonstrated unable to convert to perovskite phase by thermal annealing. In this report, a series of CsPb1- x Snx I2 Br perovskites with tunable bandgaps from 1.92 to 1.38 eV are successfully prepared for the first time via low annealing temperature (60 °C). Compared to the pure CsPbI2 Br, these Sn-Pb alloyed perovskites show superior stability. Furthermore, a novel α-phase-stabilization mechanism of the inorganic Sn-Pb alloyed perovskite by reconfiguring the perovskite crystallization process with chloride doping is provided. Simultaneously, a dense protection layer is formed by the coordination reaction between the surface lead dangling bonds and sulfate ion to retard the permeation of external oxygen and moisture, leading to less oxidation of Sn2+ in perovskite film. As a result, the fabricated all-inorganic Sn-Pb perovskite solar cells (PSCs) show a champion power conversion efficiency of 10.39% with improved phase stability and long-term ambient stability against light, heat, and humidity. This work provides a viable strategy in fabricating high-performance narrow-bandgap all-inorganic PSCs.

Dihydromyricetin ameliorates vascular calcification in chronic kidney disease by targeting AKT signaling.

Vascular calcification is highly prevalent in chronic kidney disease (CKD), and is characterized by transdifferentiation from contractile vascular smooth muscle cells (VSMCs) into an osteogenic phenotype. However, no effective and therapeutic option to prevent vascular calcification is yet available. Dihydromyricetin (DMY), a bioactive flavonoid isolated from Ampelopsis grossedentata, has been found to inhibit VSMCs proliferation and the injury-induced neointimal formation. However, whether DMY has an effect on osteogenic differentiation of VSMCs and vascular calcification is still unclear. In the present study, we sought to investigate the effect of DMY on vascular calcification in CKD and the underlying mechanism. DMY treatment significantly attenuated calcium/phosphate-induced calcification of rat and human VSMCs in a dose-dependent manner, as shown by Alizarin Red S staining and calcium content assay, associated with down-regulation of osteogenic markers including type I collagen (COL I), Runt-related transcription factor 2 (RUNX2), bone morphogenetic protein 2 (BMP2) and osteocalcin (OCN). These results were further confirmed in aortic rings ex vivo. Moreover, DMY ameliorated vascular calcification in rats with CKD. Additionally, we found that AKT signaling was activated during vascular calcification, whereas significantly inhibited by DMY administration. DMY treatment significantly reversed AKT activator-induced vascular calcification. Furthermore, inhibition of AKT signaling efficiently attenuated calcification, which was similar to that after treatment with DMY alone, and DMY had a better inhibitory effect on calcification as compared with AKT inhibitor. The present study demonstrated that DMY has a potent inhibitory role in vascular calcification partially by inhibiting AKT activation, suggesting that DMY may act as a promising therapeutic candidate for patients suffering from vascular calcification.

Trimethylamine-N-Oxide Promotes Vascular Calcification Through Activation of NLRP3 (Nucleotide-Binding Domain, Leucine-Rich-Containing Family, Pyrin Domain-Containing-3) Inflammasome and NF-κB (Nuclear Factor κB) Signals.

OBJECTIVES: Vascular calcification is highly prevalent in patients with chronic kidney disease. Increased plasma trimethylamine N-oxide (TMAO), a gut microbiota-dependent product, concentrations are found in patients undergoing hemodialysis. However, a clear mechanistic link between TMAO and vascular calcification is not yet established. In this study, we investigate whether TMAO participates in the progression of vascular calcification using in vitro, ex vivo, and in vivo models. Approach and Results: Alizarin red staining revealed that TMAO promoted calcium/phosphate-induced calcification of rat and human vascular smooth muscle cells in a dose-dependent manner, and this was confirmed by calcium content assay. Similarly, TMAO upregulated the expression of bone-related molecules including Runx2 (Runt-related transcription factor 2) and BMP2 (bone morphogenetic protein-2), suggesting that TMAO promoted osteogenic differentiation of vascular smooth muscle cells. In addition, ex vivo study also showed the positive regulatory effect of TMAO on vascular calcification. Furthermore, we found that TMAO accelerated vascular calcification in rats with chronic kidney disease, as indicated by Mico-computed tomography analysis, alizarin red staining and calcium content assay. By contrast, reducing TMAO levels by antibiotics attenuated vascular calcification in chronic kidney disease rats. Interestingly, TMAO activated NLRP3 (nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3) inflammasome and NF-κB (nuclear factor κB) signals during vascular calcification. Inhibition of NLRP3 inflammasome and NF-κB signals attenuated TMAO-induced vascular smooth muscle cell calcification. CONCLUSIONS: This study for the first time demonstrates that TMAO promotes vascular calcification through activation of NLRP3 inflammasome and NF-κB signals, suggesting the potential link between gut microbial metabolism and vascular calcification. Reducing the levels of TMAO could become a potential treatment strategy for vascular calcification in chronic kidney disease.

NCAPG, mediated by miR-378a-3p, regulates cell proliferation, cell cycle progression, and apoptosis of oral squamous cell carcinoma through the GSK-3ß/ß-catenin signaling.

Exploring the molecular mechanism of oral squamous cell carcinoma (OSCC) pathogenesis is of great significance for its improvement and therapy. Non-structural maintenance of chromatin condensin I complex subunit G (NCAPG) is responsible for chromatin condensation and is associated with the progression of many malignant tumors. This study was aimed to investigate the role of NCAPG on OSCC pathogenesis. NCAPG mRNA expression data in OSCC tissues were obtained from the Gene Expression Omnibus (GEO) database and NCAPG protein expression in OSCC cell lines was determined by western blotting analysis. The results demonstrated that NCAPG expression in OSCC tissues and cells was higher than that of normal control. Following the short interfering RNA (siRNA) knockdown of NCAPG in two OSCC cell lines, we observed that NCAPG depletion notably inhibited OSCC proliferation and cell cycle progression, as well as promoted apoptosis in vitro. Besides, silencing of NCAPG specifically inhibited the GSK-3ß/ß-catenin signaling. Furthermore, we demonstrated that NCAPG was a downstream target of miR-378a-3p. NCAPG silencing counteracted the effect of the miR-378a-3p inhibitor on cell proliferation/cycle induction. Collectively, these findings suggest that NCAPG is crucial in OSCC progression and development, and may serve as a potential therapeutic target for OSCC.