Zinc-alpha2-glycoprotein modulates blood pressure by regulating renal lipid metabolism reprogramming - mediated urinary Na+ excretion in hypertension.

AIMS: Organs modulating blood pressure are associated with a common cytokine known as adipokines. We chose Zinc-alpha2-glycoprotein (ZAG) due to its prioritized transcriptional level in the database. Previous studies showed that ZAG is involved in metabolic disorders. The aim of this study was to investigate its role in hypertension. METHODS AND RESULTS: Serum ZAG levels were assessed in hypertensive and healthy participants. Blood pressure was monitored in Azgp1-/- mice and other animal models by 24-hour ambulatory implanted telemetric transmitters and tail-cuff method. Multi-omics analysis of proteomics and metabolomics were performed to explore possible mechanisms. Serum ZAG levels were significantly decreased and associated with morning urine Na+ excretion in hypertensive participants in a cross-sectional study. This study firstly reported that Azgp1-/- mice exhibited increased blood pressure and impaired urinary Na+ excretion, which were restored by AAV9-mediated renal tubule Azgp1 rescue. Azgp1 knockout caused the reprogramming of renal lipid metabolism, and increased Na+/H+-exchanger (NHE) activity in the renal cortex. Administration with a NHE inhibitor EIPA reversed the impaired urinary Na+ excretion in Azgp1-/- mice. Moreover, the activity of carnitine palmitoyltransferase 1 (CPT1), a key enzyme of fatty acid ß-oxidation, was decreased, and the levels of malonyl-CoA, an inhibitor of CPT1, were increased in renal cortex of Azgp1-/- mice. Renal Cpt1 rescue improved urinary Na+ excretion and blood pressure in Azgp1-/- mice, accompanied by decreased renal fatty acid levels and NHE activity. Finally, administration of recombinant ZAG protein improved blood pressure and urinary Na+ excretion in SHRs. CONCLUSIONS: Deficiency of Azgp1 increased the malonyl CoA-mediated inhibition of CPT1 activity, leading to renal lipid metabolism reprogramming, resulting in accumulated fatty acids and increased NHE activity, subsequently decreasing urinary Na+ excretion and causing hypertension. These findings may provide a potential kidney-targeted therapy in the prevention and treatment of hypertension.

Clusterin-carrying extracellular vesicles derived from human umbilical cord mesenchymal stem cells restore the ovarian function of premature ovarian failure mice through activating the PI3K/AKT pathway.

BACKGROUND: Emerging evidence has highlighted the therapeutic potential of human umbilical cord mesenchymal stem cells (UC-MSCs) in chemotherapy-induced premature ovarian failure (POF). This study was designed to investigate the appropriate timing and molecular mechanism of UC-MSCs treatment for chemotherapy-induced POF. METHODS: Ovarian structure and function of mice were assessed every 3 days after injections with cyclophosphamide (CTX) and busulfan (BUS). UC-MSCs and UC-MSCs-derived extracellular vesicles (EVs) were infused into mice via the tail vein, respectively. Ovarian function was analyzed by follicle counts, the serum levels of hormones and ovarian morphology. The apoptosis and proliferation of ovarian granulosa cells were analyzed in vitro and in vivo. Label-free quantitative proteomics was used to detect the differentially expressed proteins in UC-MSC-derived EVs. RESULTS: After CTX/BUS injection, we observed that the ovarian function of POF mice was significantly deteriorated on day 9 after CTX/BUS infusion. TUNEL assay indicated that the number of apoptotic cells in the ovaries of POF mice was significantly higher than that in normal mice on day 3 after CTX/BUS injection. Transplantation of UC-MSCs on day 6 after CTX/BUS injection significantly improved ovarian function, enhanced proliferation and inhibited apoptosis of ovarian granulosa cells, whereas the therapeutic effect of UC-MSCs transplantation decreased on day 9, or day 12 after CTX/BUS injection. Moreover, EVs derived from UC-MSCs exerted similar therapeutic effects on POF. UC-MSCs-derived EVs could activate the PI3K/AKT signaling pathway and reduce ovarian granulosa cell apoptosis. Quantitative proteomics analysis revealed that clusterin (CLU) was highly expressed in the EVs of UC-MSCs. The supplementation of CLU proteins prevented ovarian granulosa cells from chemotherapy-induced apoptosis. Further mechanistic analysis showed that CLU-knockdown blocked the PI3K/AKT signaling and reversed the protective effects of UC-MSCs-derived EVs. CONCLUSIONS: Administration of UC-MSCs and UC-MSCs-derived EVs on day 6 of CTX/BUS injection could effectively improve the ovarian function of POF mice. UC-MSCs-derived EVs carrying CLU promoted proliferation and inhibited apoptosis of ovarian granulosa cells through activating the PI3K/AKT pathway. This study identifies a previously unrecognized molecular mechanism of UC-MSCs-mediated protective effects on POF, which pave the way for the use of cell-free therapeutic approach for POF.

α-Ketoglutarate promotes cardiomyocyte proliferation and heart regeneration after myocardial infarction.

The neonatal mammalian heart can regenerate following injury through cardiomyocyte proliferation but loses this potential by postnatal day 7. Stimulating adult cardiomyocytes to reenter the cell cycle remains unclear. Here we show that cardiomyocyte proliferation depends on its metabolic state. Given the connection between the tricarboxylic acid cycle and cell proliferation, we analyzed these metabolites in mouse hearts from postnatal day 0.5 to day 7 and found that α-ketoglutarate ranked highest among the decreased metabolites. Injection of α-ketoglutarate extended the window of cardiomyocyte proliferation during heart development and promoted heart regeneration after myocardial infarction by inducing adult cardiomyocyte proliferation. This was confirmed in Ogdh-siRNA-treated mice with increased α-ketoglutarate levels. Mechanistically, α-ketoglutarate decreases H3K27me3 deposition at the promoters of cell cycle genes in cardiomyocytes. Thus, α-ketoglutarate promotes cardiomyocyte proliferation through JMJD3-dependent demethylation, offering a potential approach for treating myocardial infarction.

High-throughput screening identifies ibuprofen as an sEV PD-L1 inhibitor for synergistic cancer immunotherapy.

Programmed death-ligand 1 (PD-L1) on tumor-derived small extracellular vesicles (sEVs) limits therapeutic effectiveness by interacting with the PD-1 receptor on host immune cells. Targeting the secretion of sEV PD-L1 has emerged as a promising strategy to enhance immunotherapy. However, the lack of small-molecule inhibitors poses a challenge for clinical translation. In this study, we developed a target and phenotype dual-driven high-throughput screening strategy that combined virtual screening with nanoflow-based experimental verification. We identified ibuprofen (IBP) as a novel inhibitor that effectively targeted sEV PD-L1 secretion. IBP disrupted the biogenesis and secretion of PD-L1+ sEVs in tumor cells by physically interacting with a critical regulator of sEV biogenesis, hepatocyte growth factor-regulated tyrosine kinase substrate. Notably, the mechanism of action of IBP is distinct from its commonly known targets, cyclooxygenases. Administration of IBP stimulated antitumor immunity and enhanced the efficacy of anti-PD-1 therapy in melanoma and oral squamous cell carcinoma mouse models. To address potential adverse effects, we further developed an IBP gel for topical application, which demonstrated remarkable therapeutic efficacy when combined with anti-PD-1 treatment. The discovery of this specific small inhibitor provides a promising avenue for establishing durable, systemic antitumor immunity.

4-Octyl itaconate attenuates renal tubular injury in db/db mice by activating Nrf2 and promoting PGC-1α-mediated mitochondrial biogenesis.

Objectives: The aim of this study was to investigate the mechanism of itaconate's potential effect in diabetic kidney disease.Methods: Renal immune responsive gene 1 (IRG1) levels were measured in db/db mice and streptozotocin (STZ) + high-fat diet (HFD)-induced diabetic mice. Irg1 knockout mice were generated. db/db mice were treated with 4-octyl itaconate (4-OI, 50 mg/kg), a derivative of itaconate, for 4 weeks. Renal function and morphological changes were investigated. Ultrastructural alterations were determined by transmission electron microscopy.Results: Renal IRG1 levels were reduced in two diabetic models. STZ+HFD-treated Irg1 knockout mice exhibited aggravated renal tubular injury and worsened renal function. Treatment with 4-OI lowered urinary albumin-to-creatinine ratio and blood urea nitrogen levels, and restored renal histological changes in db/db mice. It improved mitochondrial damage, increased expressions of peroxisome-proliferator-activated receptor γ coactivator-1α (PGC-1α) and mitochondrial transcription factor A (TFAM) in the renal cortex of db/db mice. These were confirmed in vitro; 4-OI improved high glucose-induced abnormal mitochondrial morphology and TFAM expression in HK-2 cells, effects that were inhibited by PGC-1α silencing. Moreover, 4-OI reduced the number of apoptotic cells in the renal cortex of db/db mice. Further study showed that 4-OI increased renal Nrf2 expression and decreased oxidative stress levels in db/db mice. In HK-2 cells, 4-OI decreased high glucose-induced mitochondrial ROS production, which was reversed by Nrf2 silencing. Nrf2 depletion also inhibited 4-OI-mediated regulation of PGC-1α, TFAM, and mitochondrial apoptotic protein expressions.Conclusions: 4-OI attenuates renal tubular injury in db/db mice by activating Nrf2 and promoting PGC-1α-mediated mitochondrial biogenesis.

Selective Generation of Reactive Oxygen Species in Photocatalytic Oxidation by Tuning Porphyrin-Based COFs' Dimensionality.

Regulating the selective generation of reactive oxygen species (ROS) is a significant challenge in the field of photocatalytic oxidation, with successful approaches still being limited. Herein, we present a strategy to selectively generate singlet oxygen (1O2) and superoxide radicals (O2•-) by tuning the dimensionality of porphyrin-based covalent organic frameworks (COFs). The transformation of COFs from three-dimensional (3D) solids to two-dimensional (2D) sheets was achieved through the reversible protonation of the imine bond. Upon irradiation, both bulk and thin-layer COF-367 can transfer energy to O2 to generate 1O2. However, thin-layer COF-367 exhibited a superior performance compared to its bulk counterpart in activating O2 to form the O2•- radicals via electron transfer. After excluding the influences of the band structure, O2 adsorption energy, and frontier orbital composition attributed to the dimensionality of the COFs, it is reasonably speculated that the variance in ROS generation arises from the differential exposure ratios of the active surfaces, leading to distinct reaction pathways between the carrier and O2. This study is the first to explore the modulation mechanism of COF dimensionality on the activation of the O2 pathway, underscoring the importance of considering COF dimensionality in photocatalytic reactions.

Efficient photocatalytic oxidative coupling of amines under visible light using a trioporphyrins-based covalent triazine framework.

Porphyrins-based porous organic polymers were widely used in photocatalytic oxidation under visible light owing to their superiority in the activation of oxygen. In contrast, the efficiency is usually limited due to the fast recombination and slow electron transfer. Herein, we report the use of a trioporphyrins-based covalent triazine framework (Por-CTF) as visible-light-active photocatalyst for the coupling oxidative of amines to imines at room temperature. By incorporating the π-conjugated porphyrin building block led to the enhanced electron transport between molecules, and the extended recombination time of excited electrons. The photocatalytic efficiency of Por-CTF is superior to that of polymer in absence of triazine framework (POP-TSP), which was prepared by radical polymerization using tetra-(4-vinylphenyl) porphyrin as monomer. Por-CTF catalyst presented excellent efficiency for various primary amines and stability. This work provides a reasonable guidance of catalyst molecular structure design for enhancing efficiency in the photocatalytic oxidation.

Role of hsa_circ_0007482 in pterygium development: insights into proliferation, apoptosis, and clinical correlations.

AIM: To investigate the impact of hsa_circ_0007482 on the proliferation and apoptosis of human pterygium fibroblasts (HPFs) and its correlation with the severity grades of pterygium. METHODS: Pterygium and normal conjunctival tissues were collected from the superior area of the same patient's eye (n=33). The correlation between pterygium severity and hsa_circ_0007482 expression using quantitative reverse-transcription polymerase chain reaction (RT-qPCR) were analyzed. Three distinct siRNA sequences targeting hsa_circ_0007482, along with a negative control sequence, were transfected into HPFs. Cell proliferation was assessed using the cell counting kit-8. Expression levels of Ki67, proliferating cell nuclear antigen (PCNA), Cyclin D1, Bax, B-cell lymphoma-2 (Bcl-2), and Caspase-3 were measured via RT-qPCR. Immunofluorescence staining was employed to detect Ki67 and vimentin expressions. Apoptosis was evaluated using flow cytometry. RESULTS: Hsa_circ_0007482 expression was significantly higher in pterygium tissues compared to normal conjunctival tissues (P<0.001). Positive correlations were observed between hsa_circ_0007482 expression and pterygium severity, thickness, and vascular density. Knockdown of hsa_circ_0007482 inhibited cell proliferation, reducing the mRNA expression of Ki67, PCNA, and Cyclin D1 in HPFs. Hsa_circ_0007482 knockdown induced apoptosis, increasing mRNA expression levels of Bax and Caspase-3, while decreasing Bcl-2 expression in HPFs. Additionally, hsa_circ_0007482 knockdown attenuated vimentin expression in HPFs. CONCLUSION: The downregulation of hsa_circ_0007482 effectively hampers cell proliferation and triggers apoptosis in HPFs. There are discernible positive correlations detected between the expression of hsa_circ_0007482 and the severity of pterygium.

A sophisticated mechanism governs Pol ζ activity in response to replication stress.

DNA polymerase ζ (Pol ζ) plays an essential role in replicating damaged DNA templates but contributes to mutagenesis due to its low fidelity. Therefore, ensuring tight control of Pol ζ's activity is critical for continuous and accurate DNA replication, yet the specific mechanisms remain unclear. This study reveals a regulation mechanism of Pol ζ activity in human cells. Under normal conditions, an autoinhibition mechanism keeps the catalytic subunit, REV3L, inactive. Upon encountering replication stress, however, ATR-mediated phosphorylation of REV3L's S279 cluster activates REV3L and triggers its degradation via a caspase-mediated pathway. This regulation confines the activity of Pol ζ, balancing its essential role against its mutations causing potential during replication stress. Overall, our findings elucidate a control scheme that fine tunes the low-fidelity polymerase activity of Pol ζ under challenging replication scenarios.

Structural basis of tolvaptan binding to the vasopressin V2 receptor.

The vasopressin V2 receptor (V2R) is a validated therapeutic target for autosomal dominant polycystic kidney disease (ADPKD), with tolvaptan being the first FDA-approved antagonist. Herein, we used Gaussian accelerated molecular dynamics simulations to investigate the spontaneous binding of tolvaptan to both active and inactive V2R conformations at the atomic-level. Overall, the binding process consists of two stages. Tolvaptan binds initially to extracellular loops 2 and 3 (ECL2/3) before overcoming an energy barrier to enter the pocket. Our simulations result highlighted key residues (e.g., R181, Y205, F287, F178) involved in this process, which were experimentally confirmed by site-directed mutagenesis. This work provides structural insights into tolvaptan-V2R interactions, potentially aiding the design of novel antagonists for V2R and other G protein-coupled receptors.

Potential Urine and Serum Biomarkers in Patients with Bladder Pain Syndrome/Interstitial Cystitis.

BACKGROUND: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a common chronic disease, and its aetiology and pathogenesis remain unclear. This study aimed to identify potential urine and serum biomarkers in patients with IC/BPS to further understand the pathogenesis and diagnosis of the disease. METHODS: Patients with IC/BPS diagnosed and treated in the First Hospital of Hebei Medical University from 1 July 2021 to 30 July 2023 were selected. The urine and serum biomarkers of 50 patients with IC/BPS were investigated and compared with the urine and serum samples of 50 healthy controls. IBM SPSS Statistics 26.0 was used for statistical analysis of the recorded data by using chi-square test, T-test and logistic regression analysis. RESULTS: Overall, 50 patients with IC/BPS (mean age, 54.20 ± 8.15 years) were included in the study. Those with history of urinary diseases, anxiety or depression were susceptible to IC/BPS. Levels of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), nerve growth factor, and prostaglandin E2 (PGE2) in urine, as well as IL-8, TNF-α, and PGE2 in serum, were found to significantly increase in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). These differences were statistically significant (p < 0.05). Multifactor analysis showed that anxiety, depression, IL-6, IL-8, TNF-α and PEG2 are risk factors for patients with IC/BPS. CONCLUSIONS: Multiple biomarkers were identified in the urine and serum of patients with IC/BPS, suggesting a potential close relationship to the pathogenesis of IC/BPS.

Comparison of conventional (basketing + dusting) and Moses (pop-dusting) holmium lasers during flexible ureteroscopy in the treatment of renal stones between 2 and 3 cm: a randomized clinical trial.

To investigate the feasibility of conventional (basketing + dusting) and Moses (pop-dusting) holmium lasers during flexible ureteroscopy (FURS) in the treatment of 2-3 cm renal calculi and to compare the efficiency and safety of the two methods, a total of 230 patients with 2-3 cm kidney stones who underwent FURS were randomly divided into the conventional group and the Moses group. The mode of lithotripsy in the conventional group was fragmentation and dusting. The mode of lithotripsy in the Moses group was dusting and pop-dusting. Clinical and perioperative variables and complications were compared between the two cohorts. Multivariate analyses of factors contributing to the stone-free rate (SFR) and operation time were performed. No statistically significant differences were found in the demographics, renal stone-related data, SFR, or complications between the cohorts. The laser energy was higher in the Moses cohort than in the conventional cohort (119.3 ± 15.2 vs. 92.8 ± 15.1 kJ; P < 0.001), and the operation time was shorter in the Moses cohort than in the conventional cohort (99.5 ± 18.9 vs. 105.3 ± 13.7 min; P = 0.009). When there was isolated stone, the operation time was shorter in the Moses cohort than in the conventional cohort (99.6 ± 17.5 vs. 111.4 ± 10.7 min; P < 0.001), while there was no significant difference between the two cohorts when there were multiple stones (99.5 ± 20 vs. 101.2 ± 14 min; P = 0.415). Multivariate analyses found that an increase in stone volume can decrease the SFR and prolong the operation time, and use of a Moses laser can shorten the operation time. Both holmium laser modes during FURS can effectively treat 2-3 cm renal calculi. The Moses mode is recommended as the first choice for the treatment of isolated 2-3 cm renal stones. When treating multiple stones, the efficiency of these two laser modalities is the same. TRIAL REGISTRATION: ChiCTR2200056091.

2D Exfoliation Chemistry Towards Covalent Pseudo-Layered Phosphate Framework Derived by Radical/Strain-Synergistical Process.

2D compounds exfoliated from weakly bonded bulk materials with van der Waals (vdW) interaction are easily accessible. However, the strong internal ionic/covalent bonding of most inorganic crystal frameworks greatly hinders 2D material exfoliation. Herein, we first proposed a radical/strain-synergistic strategy to exfoliate non-vdW interacting pseudo-layered phosphate framework. Specifically, hydroxyl radicals (⋅OH) distort the covalent bond irreversibly, meanwhile, H2O molecules as solvents, further accelerating interlayered ionic bond breakage but mechanical expansion. The innovative 2D laminar NASICON-type Na3V2(PO4)2O2F crystal, exfoliated by ⋅OH/H2O synergistic strategy, exhibits enhanced sodium-ion storage capacity, high-rate performance (85.7 mAh g-1 at 20 C), cyclic life (2300 cycles), and ion migration rates, compared with the bulk framework. Importantly, this chemical/physical dual driving technique realized the effective exfoliation for strongly coupled pseudo-layered frameworks, which accelerates 2D functional material development.

CXCR2/Snail-1-Induced Epithelial-Mesenchymal Transition in the Formation and Progression of RCC with Inferior Vena Cava Tumour Thrombus.

BACKGROUND: Renal cell carcinoma (RCC), a common and highly invasive malignant tumour, presents clinical challenges due to its propensity for easy metastasis. Inferior vena cava tumour thrombus is a common RCC complication significantly impacting patient prognosis. This study investigates C-X-C chemokine receptor type 2 (CXCR2)/Snail-1-induced epithelial-mesenchymal transition (EMT) in RCC with inferior vena cava tumour thrombus. METHODS: Tissues from 51 RCC patients were analysed for CXCR2 and Snail-1 Messenger Ribonucleic Acid (mRNA) levels using Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). Elevated levels of both were observed in tumour and inferior vena cava tumour thrombus tissues. Using Short Hairpin RNA (shRNA) technology, we inhibited CXCR2 and Snail-1 expression to investigate their impact on EMT, invasiveness, and metastatic potential in RCC cells. RESULTS: Compared with that in the Short Hairpin RNA-Negative Control (ShNC) group, inhibition of CXCR2 and Snail-1 suppressed the degree of EMT, invasiveness, and metastatic ability of RCC cells (p < 0.01). Further mechanistic studies showed that CXCR2/Snail-1 participated in the formation and progression of RCC by regulating the extracellular signal-regulated kinase 1/2 (ERK1/2) signalling pathways. Additionally, compared with that in the ShNC group, knockdown of CXCR2 and Snail-1 significantly inhibited the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9; p < 0.01), thereby regulating the metastasis of RCC. CONCLUSIONS: Our findings suggest that CXCR2/Snail-1-induced EMT plays an important role in the formation and progression of RCC with inferior vena cava tumour thrombus. CXCR2/Snail-1 participates in the invasion and metastasis of RCC by regulating the expression of multiple signalling pathways and related genes. These results provide new insights and directions for the treatment of RCC.

Rare earth elements induced electronic engineering in Rh cluster toward efficient alkaline hydrogen evolution reaction.

The unique electronic and crystal structures of rare earth metals (RE) offer promising opportunities for enhancing the hydrogen evolution reaction (HER) properties of materials. In this work, a series of RE (Sm, Nd, Pr and Ho)-doped Rh@NSPC (NSPC stands for N, S co-doped porous carbon nanosheets) with sizes less than 2 nm are prepared, utilizing a simple, rapid and solvent-free joule-heat pyrolysis method for the first time. The optimized Sm-Rh@NSPC achieves HER performance. The high-catalytic performance and stability of Sm-Rh@NSPC are attributed to the synergistic electronic interactions between Sm and Rh clusters, leading to an increase in the electron cloud density of Rh, which promotes the adsorption of H+, the dissociation of Rh-H bonds and the release of H2. Notably, the overpotential of the Sm-Rh@NSPC catalyst is a mere 18.1 mV at current density of 10 mAcm-2, with a Tafel slope of only 15.2 mV dec-1. Furthermore, it exhibits stable operation in a 1.0 M KOH electrolyte at 10 mA cm-2 for more than 100 h. This study provides new insights into the synthesis of composite RE hybrid cluster nanocatalysts and their RE-enhanced electrocatalytic performance. It also introduces fresh perspectives for the development of efficient electrocatalysts.

HOXB9 promotes osteosarcoma cell survival and malignancy under glucose starvation via upregulating SPP1 expression.

Homeobox B9 (HOXB9) has been shown to play a critical role in several tumors. However, the precise biological mechanisms and functions of HOXB9 in osteosarcoma remain largely unknown. In this study, we found that HOXB9 was increased upon glucose starvation. Elevated HOXB9 suppressed osteosarcoma cell death and supported cell growth and migration under glucose starvation. Further mechanistic studies demonstrated that HOXB9 directly bound to the promoter of secreted phosphoprotein 1 (SPP1) and transcriptionally upregulated SPP1 expression which then led cell death decrease and cell growth increase under glucose deprivation environment. Clinically, HOXB9 was significantly upregulated in osteosarcoma compared with normal tissues and increase of HOXB9 expression was positively associated with the elevation of SPP1 in osteosarcoma. Overall, our study illustrates that HOXB9 contributes to malignancy in osteosarcoma and inhibits cell death through transcriptional upregulating SPP1 under glucose starvation.

NUCB2 inhibition antagonizes osteosarcoma progression and promotes anti-tumor immunity through inactivating NUCKS1/CXCL8 axis.

The oncogenic properties of Nucleobindin2 (NUCB2) have been observed in various cancer types. Nevertheless, the precise understanding of the biological functions and regulatory mechanisms of NUCB2 in osteosarcoma remains limited. This investigation reported that NUCB2 was significantly increased upon glucose deprivation-induced metabolic stress. Elevated NUCB2 suppressed glucose deprivation-induced cell death and reactive oxygen species (ROS) increase. Depletion of NUCB2 resulted in a reduction in osteosarcoma cell proliferation as well as metastatic potential in vitro and in vivo. Mechanically, NUCB2 ablation suppressed C-X-C Motif Chemokine Ligand 8 (CXCL8) expression which then reduced programmed cell death 1 ligand 1 (PD-L1) expression and stimulated anti-tumor immunity mediated through cytotoxic T cells. Importantly, a combination of NUCB2 depletion with anti-PD-L1 treatment improved anti-tumor T-cell immunity in vivo. Moreover, we further demonstrated that NUCB2 interacted with NUCKS1 to inhibit its degradation, which is responsible for the transcriptional regulation of CXCL8 expression. Altogether, the outcome emphasizes the function of NUCB2 in osteosarcoma and indicates that NUCB2 elevates osteosarcoma progression and immunosuppressive microenvironment through the NUCKS1/CXCL8 pathway.

Neutrophil Elastase Degrades Histone Deacetylases and Sirtuin 1 in Primary Human Monocyte Derived Macrophages.

Neutrophil elastase (NE) is taken up by macrophages, retains intracellular protease activity, and induces a pro-inflammatory phenotype. However, the mechanism of NE-induced pro-inflammatory polarization of macrophages is not well understood. We hypothesized that intracellular NE degrades histone deacetylases (HDAC) and Sirtuins, disrupting the balance of lysine acetylation and deacetylation and resulting in nuclear to cytoplasmic translocation of a major alarmin, High Mobility Group Box 1 (HMGB1), a pro-inflammatory response in macrophages. Human blood monocytes were obtained from healthy donors or from subjects with cystic fibrosis (CF) or chronic obstructive pulmonary disease (COPD). Monocytes were differentiated into blood monocyte derived macrophages (BMDMs) in vitro. Human BMDMs were exposed to NE or control vehicle, and the abundance of HDACs and Sirtuins was determined by Western blotting of total cell lysates or nuclear extracts or determined by ELISA. HDAC, Sirtuin, and Histone acetyltransferase (HAT) activities were measured. NE degraded most HDACs and Sirtuin (Sirt)1, resulting in decreased HDAC and sirtuin activities, with minimal change in HAT activity. We then evaluated whether the NE-induced loss of Sirt activity or loss of HDAC activities would alter the cellular localization of HMGB1. NE treatment or treatment with Trichostatin A (TSA), a global HDAC inhibitor, both increased HMGB1 translocation from the nucleus to the cytoplasm, consistent with HMGB1 activation. NE significantly degraded Class I and II HDAC family members and Sirt 1, which shifted BMDMs to a pro-inflammatory phenotype.

Biomass-derived cellulose nanocrystals modified nZVI for enhanced tetrabromobisphenol A (TBBPA) removal.

Nano zero-valent iron (nZVI) is an advanced environmental functional material for the degradation of tetrabromobisphenol A (TBBPA). However, high surface energy, self-agglomeration and low electron selectivity limit degradation rate and complete debromination of bare nZVI. Herein, we presented biomass-derived cellulose nanocrystals (CNC) modified nZVI (CNC/nZVI) for enhanced TBBPA removal. The effects of raw material (straw, filter paper and cotton), process (time, type and concentration of acid hydrolysis) and synthesis methods (in-situ and ex-situ) on fabrication of CNC/nZVI were systematically evaluated based on TBBPA removal performance. The optimized CNC-S/nZVI(in) was prepared via in-situ liquid-phase reduction using straw as raw material of CNC and processing through 44 % H2SO4 for 165 min. Characterizations illustrated nZVI was anchored to the active sites at CNC interface through electrostatic interactions, hydrogen bonds and FeO coordinations. The batch experiments showed 0.5 g/L CNC-S/nZVI(in) achieved 96.5 % removal efficiency at pH = 7 for 10 mg/L initial TBBPA. The enhanced TBBPA dehalogenation by CNC-S/nZVI(in), involving in initial adsorption, reduction process and partial detachment of debrominated products, were possibly attributed to elevated pre-adsorption capacity and high-efficiency delivery of electrons synergistically. This study indicated that fine-tuned fabrication of CNC/nZVI could potentially be a promising alternative for remediation of TBBPA-contaminated aquatic environments.