Azimuthal polarized quasi-bound states in the continuum based on rotational symmetry breaking.

Bound states in the continuum (BICs) allow to obtain an ultrahigh-quality-factor optical cavity. Nevertheless, BICs must be extended in one or more directions, substantially increasing the device footprint. Although super-cavity mode quasi-BICs supported by single nanopillars have been demonstrated recently, their low-quality factor and localized electromagnetic field inside the dielectric nanopillar are insufficient for high-sensitivity refractive index sensing applications. We propose a ring structure rotated by a dielectric sectorial nanostructure, which can achieve a high quality factor by breaking the rotational symmetry of the ring structure with a footprint as small as 3 µm2. As a straightforward application, we demonstrate high performance local refractive index and nanoscale film thickness sensing based on rotational symmetry breaking induced BICs. These BICs reach quality factor and sensitivity of one order of magnitude better than those of conventional super-cavity mode BICs. The proposed method provides insights into the design of compact high quality factor photonic devices, opening up new possibilities for applications in refractive index and nanoscale film thickness sensing.

Inhibition of neutrophil extracellular trap formation ameliorates neuroinflammation and neuronal apoptosis via STING-dependent IRE1α/ASK1/JNK signaling pathway in mice with traumatic brain injury.

BACKGROUND: Neuroinflammation is one of the most important pathogeneses in secondary brain injury after traumatic brain injury (TBI). Neutrophil extracellular traps (NETs) forming neutrophils were found throughout the brain tissue of TBI patients and elevated plasma NET biomarkers correlated with worse outcomes. However, the biological function and underlying mechanisms of NETs in TBI-induced neural damage are not yet fully understood. Here, we used Cl-amidine, a selective inhibitor of NETs to investigate the role of NETs in neural damage after TBI. METHODS: Controlled cortical impact model was performed to establish TBI. Cl-amidine, 2'3'-cGAMP (an activator of stimulating Interferon genes (STING)), C-176 (a selective STING inhibitor), and Kira6 [a selectively phosphorylated inositol-requiring enzyme-1 alpha [IRE1α] inhibitor] were administrated to explore the mechanism by which NETs promote neuroinflammation and neuronal apoptosis after TBI. Peptidyl arginine deiminase 4 (PAD4), an essential enzyme for neutrophil extracellular trap formation, is overexpressed with adenoviruses in the cortex of mice 1 day before TBI. The short-term neurobehavior tests, magnetic resonance imaging (MRI), laser speckle contrast imaging (LSCI), Evans blue extravasation assay, Fluoro-Jade C (FJC), TUNEL, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), western blotting, and quantitative-PCR were performed in this study. RESULTS: Neutrophils form NETs presenting in the circulation and brain at 3 days after TBI. NETs inhibitor Cl-amidine treatment improved short-term neurological functions, reduced cerebral lesion volume, reduced brain edema, and restored cerebral blood flow (CBF) after TBI. In addition, Cl-amidine exerted neuroprotective effects by attenuating BBB disruption, inhibiting immune cell infiltration, and alleviating neuronal death after TBI. Moreover, Cl-amidine treatment inhibited microglia/macrophage pro-inflammatory polarization and promoted anti-inflammatory polarization at 3 days after TBI. Mechanistically, STING ligand 2'3'-cGAMP abolished the neuroprotection of Cl-amidine via IRE1α/ASK1/JNK signaling pathway after TBI. Importantly, overexpression of PAD4 promotes neuroinflammation and neuronal death via the IRE1α/ASK1/JNK signaling pathway after TBI. However, STING inhibitor C-176 or IRE1α inhibitor Kira6 effectively abolished the neurodestructive effects of PAD4 overexpression after TBI. CONCLUSION: Altogether, we are the first to demonstrate that NETs inhibition with Cl-amidine ameliorated neuroinflammation, neuronal apoptosis, and neurological deficits via STING-dependent IRE1α/ASK1/JNK signaling pathway after TBI. Thus, Cl-amidine treatment may provide a promising therapeutic approach for the early management of TBI.

2D Piezoelectric BiVO4 Artificial Nanozyme with Adjustable Vanadium Vacancy for Ultrasound Enhanced Piezoelectric/Sonodynamic Therapy.

Increasing the yield of reactive oxygen species (ROS) to enhance oxidative stress in cells is an eternal goal in cancer therapy. In this study, BiVO4 artificial nanozyme is developed with adjustable vanadium vacancy for ultrasound (US) enhanced piezoelectric/sonodynamic therapy. Under US excitation, the vanadium vacancy-rich BiVO4 nanosheets (abbreviated Vv -r BiVO4 NSs) facilitate the generation of a large number of electrons to improve the ROS yield. Meanwhile, the mechanical strain imposed by US irradiation makes the Vv -r BiVO4 NSs display a typical piezoelectric response, which tilts the conduction band to be more negative and the valance band more positive than the redox potentials of O2 /O2 •- and H2 O/·OH, boosting the efficiency of ROS generation. Both density functional theory calculations and experiments confirm that the introduction of cationic vacancy can improve the sonodynamic effect. As expected, Vv -r BiVO4 NSs have better peroxidase enzyme catalytic and glutathione depletion activities, resulting in increased intracellular oxidative stress. This triple amplification strategy of oxidative stress induced by US substantially inhibits the growth of cancer cells. The work may open an avenue to achieve a synergetic therapy by introducing cationic vacancy, broadening the biomedical use of piezoelectric materials.

Urchin-Like Structured MoO2 /Mo3 P/Mo2 C Triple-Interface Heterojunction Encapsulated within Nitrogen-Doped Carbon for Enhanced Hydrogen Evolution Reaction.

The development of highly efficient and cost-effective hydrogen evolution reaction (HER) catalysts is highly desirable to efficiently promote the HER process, especially under alkaline condition. Herein, a polyoxometalates-organic-complex-induced carbonization method is developed to construct MoO2 /Mo3 P/Mo2 C triple-interface heterojunction encapsulated into nitrogen-doped carbon with urchin-like structure using ammonium phosphomolybdate and dopamine. Furthermore, the mass ratio of dopamine and ammonium phosphomolybdate is found critical for the successful formation of such triple-interface heterojunction. Theoretical calculation results demonstrate that such triple-interface heterojunctions possess thermodynamically favorable water dissociation Gibbs free energy (ΔGH2O ) of -1.28 eV and hydrogen adsorption Gibbs free energy (ΔGH* ) of -0.41 eV due to the synergistic effect of Mo2 C and Mo3 P as water dissociation site and H* adsorption/desorption sites during the HER process in comparison to the corresponding single components. Notably, the optimal heterostructures exhibit the highest HER activity with the low overpotential of 69 mV at the current density of 10 mA cm-2 and a small Tafel slope of 60.4 mV dec-1 as well as good long-term stability for 125 h. Such remarkable results have been theoretically and experimentally proven to be due to the synergistic effect between the unique heterostructures and the encapsulated nitrogen-doped carbon.

Advanced glycation end products impair bone marrow mesenchymal stem cells osteogenesis in periodontitis with diabetes via FTO-mediated N6-methyladenosine modification of sclerostin.

BACKGROUND: Diabetes mellitus (DM) and periodontitis are two prevalent diseases with mutual influence. Accumulation of advanced glycation end products (AGEs) in hyperglycemia may impair cell function and worsen periodontal conditions. N6-methyladenosine (m6A) is an important post-transcriptional modification in RNAs that regulates cell fate determinant and progression of diseases. However, whether m6A methylation participates in the process of periodontitis with diabetes is unclear. Thus, we aimed to investigate the effects of AGEs on bone marrow mesenchymal stem cells (BMSCs), elucidate the m6A modification mechanism in diabetes-associated periodontitis. METHODS: Periodontitis with diabetes were established by high-fat diet/streptozotocin injection and silk ligation. M6A modifications in alveolar bone were demonstrated by RNA immunoprecipitation sequence. BMSCs treated with AGEs, fat mass and obesity associated (FTO) protein knockdown and sclerostin (SOST) interference were evaluated by quantitative polymerase chain reaction, western blot, immunofluorescence, alkaline phosphatase and Alizarin red S staining. RESULTS: Diabetes damaged alveolar bone regeneration was validated in vivo. In vitro experiments showed AGEs inhibited BMSCs osteogenesis and influenced the FTO expression and m6A level in total RNA. FTO knockdown increased the m6A levels and reversed the AGE-induced inhibition of BMSCs differentiation. Mechanically, FTO regulated m6A modification on SOST transcripts, and AGEs affected the binding of FTO to SOST transcripts. FTO knockdown accelerated the degradation of SOST mRNA in presence of AGEs. Interference with SOST expression in AGE-treated BMSCs partially rescued the osteogenesis by activating Wnt Signaling. CONCLUSIONS: AGEs impaired BMSCs osteogenesis by regulating SOST in an m6A-dependent manner, presenting a promising method for bone regeneration treatment of periodontitis with diabetes.

Elevated Interleukin-10 Levels Are Associated with Low Platelet Count and Poor Prognosis in 90 Adult Patients with Hemophagocytic Lymphohistiocytosis.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome characterized by excessive inflammatory responses. This study explored the association between laboratory characteristics and outcomes in adult patients with HLH. METHODS: The adult patients diagnosed with HLH at the Second Hospital of Shanxi Medical University from September 2016 to September 2021 were retrospectively analyzed in this study. RESULTS: A total of 90 HLH patients were included. Among them, 60% were males, with a median age at diagnosis of 54 years. More than 85% of HLH patients presented with fever, splenomegaly, and cytopenias. IL-10 and IL-6 were elevated in 93.3% and 91.1% of patients, respectively. Elevated IL-10 levels were associated with lower platelet counts (r = -0.37, p < 0.001). Infections were seen in 46.7% (42/90) of cases. 29 patients with malignancy-associated HLH had T- or NK-cell (n = 16) or B-cell (n = 12) lymphoma. Autoimmune diseases accounted for 21.1% (19/90). Treatment was variable. In total, 36 patients survived (40%). The median overall survival (OS) was 1.5 months (95% confidence intervals [CI]: 0.2-2.8 months), with a 1-year OS of 40.9%. Patients with autoimmune diseases had markedly longer survival than those triggered by infection and malignancy (p < 0.001). Multivariate Cox regression analysis indicated that treatment delays (hazard ratios 0.36, 95% CI: 0.14-0.94, p = 0.036), platelet count (2.33, 1.30-4.18, p = 0.005), and IL-10 (2.07, 1.16-3.68, p = 0.014) were independent risk factors for poor outcome. CONCLUSION: Infection and lymphoma are the leading causes of HLH in adult patients with heterogeneous clinical manifestations. Survival of adult HLH is frustrating, especially those associated with malignancies. Besides, elevated IL-10 levels were associated with lower platelet counts, and these two markers were independent risk factors for poor prognosis. Earlier treatment led to better outcomes.

Prognostic value of left atrial mechanics in cardiac light-chain amyloidosis with preserved ejection fraction: a cohort study.

BACKGROUND: Light-chain amyloidosis is a plasma cell disorder associated with poor outcomes, especially when the heart is involved. The characteristics of left atrial (LA) function and its prognostic implications in cardiac amyloidosis (CA) have not been fully investigated. METHODS: Between April 2014 and June 2019, 93 patients with a diagnosis of CA, normal left ventricular ejection fraction (LVEF) and sinus rhythm were included. Their clinical, baseline echocardiographic and follow-up data were investigated. LA function, including LA strain and strain rate, was assessed using 2D speckle tracking echocardiography in different LA functional phases. RESULTS: Among all patients, 38 (40.9%) died. Multivariate Cox regression analyses showed that LA mechanics regarding LA reservoir and booster pump functions were independent predictors for overall survival. Traditional echocardiographic parameters for LA structure like LA volume index and LA width were not associated with mortality. Moreover, LA strain and strain rate in reservoir and contractile phases improved the discrimination and goodness of fit of the conventional prognostic model, the Mayo criteria 2004 and 2012, in our study population. Decreased LA mechanics were associated with impaired left ventricular (LV) systolic and diastolic function, and LA reservoir and contractile functions were associated with LA structure. CONCLUSIONS: Assessment of LA reservoir and contractile functions via 2D speckle tracking echocardiographic LA mechanical indices provide clinical and prognostic insights into cardiac light-chain amyloidosis patients, especially those with preserved EF and sinus rhythm. Emphasizing the monitoring of LA function may be beneficial for the prognosis prediction of CA.

Electrophysiological, structural, and functional disorders in patients with inflammatory cardiomyopathy secondary to inflammatory myopathy.

BACKGROUND: Inflammatory cardiomyopathy (IC) is a syndrome with chronic myocarditis and cardiac remodeling. This study aimed to explore predicting factors of adverse outcomes in patients with IC secondary to idiopathic inflammatory myopathy (IIM-IC). METHODS: By means of a single-center retrospective study, 52 patients with IIM-IC at Peking Union Medical College Hospital were identified from January 1999 to June 2019. Electrocardiogram and echocardiography data were analyzed for the primary outcome (defined as all-cause death) and secondary outcomes (defined as re-hospitalization of heart failure and all-cause death), using regression and survival analysis. RESULTS: The prevalence of atrial fibrillation, ventricular tachycardia, Q-wave abnormality, left ventricular conduction abnormalities, and reduced left ventricular ejection fraction (LVEF) (≤40%) were 65.4%, 67.3%, 67.3%, 61.6%, and 50.5%. After a median follow-up of 2 years (IQR 0.8-3.0), 26 cases were readmitted due to heart failure. Twenty-two deaths were recorded, including 20 cardiogenic deaths. Among the patients with adverse events, the incidence of poor R-wave progression, low-voltage of the limb leads, Q-wave abnormality, QRS duration >130 ms, left ventricular enlargement, and impaired systolic function were higher. Kaplan-Meier analysis showed that Q-wave abnormality, limb leads low-voltage, LVEF ≤40%, and left ventricular end-diastolic dimension >60 mm were correlated with shorter survival. However, multivariate Cox regression analysis revealed that only Q-wave abnormality (HR = 12.315) and LVEF ≤40% (HR = 5.616) were independent risk factors for all-cause death. CONCLUSION: Q-wave abnormality and reduced LVEF are predictive of poor prognosis in patients with IIM-IC.

Most Analgesia Treatments Have No Clinical Significance for Anterior Cruciate Ligament Reconstruction: A Network Meta-analysis of 66 Randomized Controlled Trials.

PURPOSE: To assess the relative efficacy of several clinical treatments for postoperative analgesia of anterior cruciate ligament reconstruction through network meta-analysis based on multiple published randomized controlled trials. METHODS: We searched PubMed, the Cochrane library, EMBASE, and Web of Science, each from inception until February 15, 2021. Outcomes including pain scores at rest (visual analog scale, numerical rating scales, and other scales, which were converted to a standardized 0-10 scale), morphine consumption, and complications were meta-analyzed. Quality of the included studies was assessed using the Cochrane risk-of-bias tool. The authors defined the best choice for postoperative analgesia as the one that had significant difference in pain scores, morphine consumption, and had no significant difference in the risk of complications compared with placebo in the initial 48 postoperative hours. RESULTS: In total, 66 studies with 4,168 patients were included in this network meta-analysis. Only periarticular infiltration was significantly superior to placebo in pain scores and morphine consumption (pain at 2 hours: mean difference [MD] -0.74, 95% confidence interval [CI] -1.36 to -0.12; pain at 6 hours: MD -0.81, 95% CI -1.42 to -0.21; pain at 12 hours: MD -0.85, 95% CI -1.53 to -0.17; pain at 24 hours: MD -0.80, 95% CI -1.19 to -0.40; morphine consumption at 24 hours: MD -10.12, 95% CI -14.31 to -5.93; morphine consumption at 48 hours: MD -5.62, 95% CI -6.74 to -4.51). Periarticular infiltration did not increase the risk of complications compared with placebo (nausea and vomiting: odds ratio [OR] 0.63, 95% CI 0.34-1.16; pruritus: OR 0.74, 95% CI 0.35-1.58; urinary retention: OR 0.55, 95% CI 0.25-1.23). In addition, There was no significant difference between adductor canal block and femoral nerve block in pain scores and morphine consumption (pain at 2 hours: MD -0.01, 95% CI -1.44 to 1.42; pain at 6 hours: MD 0.29, 95% CI -0.28 to 0.86; pain at 12 hours: MD 0.36, 95% CI -0.44 to 1.16; pain at 24 hours: MD 0.26, 95% CI -0.22 to 0.75; pain at 48 hours: MD -0.36, 95% CI -0.97 to 0.24; morphine at 24 hours: MD 1.04, 95% CI -4.70 to 6.79; morphine at 48 hours: MD -0.32, 95% CI -0.70 to 0.07; postoperative nausea and vomiting: OR 1.07, 95% CI 0.55-2.09; pruritus: OR 1.36, 95% CI 0.66-2.79; urinary retention: OR 1.41, 95% CI 0.37-5.29). CONCLUSIONS: Based on current evidence, most analgesic methods could result in lower pain scores and decrease morphine consumption when compared with placebo; however, differences between methods were small and inconsistent. There seemed to be no significant difference between adductor canal block and femoral nerve block in pain score, morphine consumption and complications. LEVEL OF EVIDENCE: Level I, meta-analysis of Level I RCTs.

DEPP Deficiency Contributes to Browning of White Adipose Tissue.

Decidual protein induced by progesterone (DEPP) was originally identified as a modulator in the process of decidualization in the endometrium. Here, we define that DEPP is involved in adipose tissue thermogenesis, which contributes to metabolic regulation. Knockdown of DEPP suppressed adipocyte differentiation and lipid accumulation in 3T3-L1 cells, induced expression of brown adipose tissue (BAT) markers in primary brown adipocyte and induced mouse embryonic fibroblasts (MEFs) differentiation to brown adipocytes. Moreover, DEPP deficiency in mice induced white adipocyte browning and enhanced BAT activity. Cold exposure stimulated more browning of white adipose tissue (WAT) and maintained higher body temperature in DEPP knockout mice compared to that in wild-type control mice. DEPP deficiency also protected mice against high-fat-diet-induced insulin resistance. Mechanistic studies demonstrated that DEPP competitively binds SIRT1, inhibiting the interaction between peroxisome proliferator-activated receptor gamma (PPARγ) and Sirtuin 1 (SIRT1). Collectively, these findings suggest that DEPP plays a crucial role in orchestrating thermogenesis through regulating adipocyte programs and thus might be a potential target for the treatment of metabolic disorders.

High-Throughput Metabolic Soft-Spot Identification in Liver Microsomes by LC/UV/MS: Application of a Single Variable Incubation Time Approach.

CYP-mediated fast metabolism may lead to poor bioavailability, fast drug clearance and significant drug interaction. Thus, metabolic stability screening in human liver microsomes (HLM) followed by metabolic soft-spot identification (MSSID) is routinely conducted in drug discovery. Liver microsomal incubations of testing compounds with fixed single or multiple incubation time(s) and quantitative and qualitative analysis of metabolites using high-resolution mass spectrometry are routinely employed in MSSID assays. The major objective of this study was to develop and validate a simple, effective, and high-throughput assay for determining metabolic soft-spots of testing compounds in liver microsomes using a single variable incubation time and LC/UV/MS. Model compounds (verapamil, dextromethorphan, buspirone, mirtazapine, saquinavir, midazolam, amodiaquine) were incubated at 3 or 5 µM with HLM for a single variable incubation time between 1 and 60 min based on predetermined metabolic stability data. As a result, disappearances of the parents were around 20-40%, and only one or a few primary metabolites were generated as major metabolite(s) without notable formation of secondary metabolites. The unique metabolite profiles generated from the optimal incubation conditions enabled LC/UV to perform direct quantitative estimation for identifying major metabolites. Consequently, structural characterization by LC/MS focused on one or a few major primary metabolite(s) rather than many metabolites including secondary metabolites. Furthermore, generic data-dependent acquisition methods were utilized to enable Q-TOF and Qtrap to continuously record full MS and MS/MS spectral data of major metabolites for post-acquisition data-mining and interpretation. Results from analyzing metabolic soft-spots of the seven model compounds demonstrated that the novel MSSID assay can substantially simplify metabolic soft-spot identification and is well suited for high-throughput analysis in lead optimization.

Association between diabetes and dental implant complications: a systematic review and meta-analysis.

OBJECTIVES: The aim of this study was to explore the possible association between diabetes mellitus and dental implant complications. MATERIAL AND METHODS: A systematic literature review was conducted to answer the following PICO (Participants, Intervention, Comparison, and Outcome) question: Is there association between diabetes mellitus and dental implant complications? Two independent searchers performed a literature search of the PubMed/MEDLINE, Web of Science, Cochrane Library and EMBASE databases for studies published until February 2020, focussing on studies including continuous outcomes, marginal bone loss (primary outcome), probing depth, and bleeding upon probing (secondary outcomes). RESULTS AND CONCLUSIONS: A final total of 10 published studies were included in this systematic review. There were statistically significant differences between the groups with regard to marginal bone loss (p < .00001), probing depth (p < .00001) and bleeding around dental implants (p < .00001), and subjects without diabetes had lower complication rates. Additionally, in the subgroup analysis performed with loading time and HbA1c levels, a more evident association was found in immediate loading for probing depth. Moreover, the analysis results of bleeding around dental implants suggested that as HbA1c level increases, the bleeding of the tissues surrounding the implant will also increase. With regard to dental implant complications, there were statistically significant differences favouring patients without diabetes mellitus.

Combining Mass Spectrometry with Paternò-Büchi Reaction to Determine Double-Bond Positions in Lipids at the Single-Cell Level.

Single cell MS (SCMS) techniques are under rapid development for molecular analysis of individual cells among heterogeneous populations. Lipids are basic cellular constituents playing essential functions in energy storage and the cellular signaling processes of cells. Unsaturated lipids are characterized with one or multiple carbon-carbon double (C═C) bonds, and they are critical for cell functions and human diseases. Characterizing unsaturated lipids in single cells allows for better understanding of metabolomic biomarkers and therapeutic targets of rare cells (e.g., cancer stem cells); however, these studies remain challenging. We developed a new technique using a micropipette needle, in which Paternò-Büchi (PB) reactions at C═C bond can be induced, to determine locations of C═C bonds in unsaturated lipids at the single-cell level. The micropipette needle is produced by combining a pulled glass capillary needle with a fused silica capillary. Cell lysis solvent and PB reagent (acetone or benzophenone) are delivered into the micropipette needle (tip size ≈ 15 um) through a fused silica capillary. The capillary needle plays multiple functions (i.e., single cell sampling probe, cell lysis container, microreactor, and nano-ESI emitter) in the experiments. Both regular (no reaction) and reactive (with PB reaction) SCMS analyses of the same cell can be achieved. C═C bond locations were determined from MS scan and MS/MS of PB products assisted by Python programs. This technique can potentially be used for other reactive SCMS studies to enhance molecular analysis for broad ranges of single cells.

Clinical Characteristics, Treatment, and Outcomes in Patients with Idiopathic Inflammatory Myopathy Concomitant with Heart Failure.

This study sought to evaluate clinical features, treatment patterns, and outcomes of patients with idiopathic inflammatory myopathy (IIM) complicated by heart failure (HF). Thirty-two patients with IIM-HF admitted to the Peking Union Medical College Hospital between January 1999 and January 2018 were retrospectively reviewed, including 14 patients with polymyositis, 11 with dermatomyositis, and 7 with overlap syndrome. Survivors and no-survivors were compared on clinical characteristics and treatment. Although systemic symptoms were variable, all patients presented with elevated troponin I. Rapid atrial arrhythmia was the most frequent arrhythmia. Systolic dysfunction and restrictive diastolic dysfunction were typical presentations in echocardiography. Twenty-nine patients were followed up for a median of 2.8 years (0.1 month to 11 years). We recorded 13 deaths of cardiogenic cause, 1 of serious IIM, and 3 of infective complications. The median survival time from diagnosis of IIM-HF to all-cause mortality was 8.4 months (range from 1 month to 5 years). Both all-cause deaths and cardiogenic deaths were more reported in the methotrexate-alone group than in the combination therapy group (6/7 versus 3/10, P = 0.050; 5/6 versus 2/9, P = 0.041). Combination therapy including methotrexate (HR = 0.188, 95%CI 0.040-0.871, P = 0.033) and taking ß-receptor blockers (HR = 0.249, 95%CI 0.086-0.719, P = 0.010) was associated with reduced risk of all-cause deaths. In conclusion, elevated troponin I, atrial arrhythmia, and systolic and restrictive diastolic dysfunction are typical characteristics of IIM-HF. Combined immunosuppression that includes methotrexate and ß-receptor blockers seems to be important to improve survival.

Identification of an Oleanane-Type Triterpene Hedragonic Acid as a Novel Farnesoid X Receptor Ligand with Liver Protective Effects and Anti-inflammatory Activity.

Farnesoid X receptor (FXR) and G-protein-coupled bile acid receptor 1 (GPBAR1) are two important bile acid (BA) receptors. As non-BAs drug template for GPBAR1, none of the natural oleanane-type triterpenes have been reported as FXR ligands, despite FXR and GPBAR1 having similar binding pockets for BAs. Here, we report the natural triterpene hedragonic acid that has been isolated from the stem and root of Celastrus orbiculatus Thunb. (COT) as an effective agonist for FXR. Both biochemical amplified luminescent proximity homogeneous assay and cell-based reporter assays showed that hedragonic acid regulated the transcriptional activity of FXR. Circular dichroism spectroscopy further suggested the conformational changes of FXR upon the binding of hedragonic acid. Interestingly, the crystal structure of hedragonic acid-bound FXR revealed a unique binding mode with hedragonic acid occupying a novel binding pocket different from the classic binding position. The structural comparison between hedragonic acid-bound FXR and oleanolic acid-bound GPBAR1 explained the molecular basis for the selectivity of oleanane-type triterpenes for FXR. Moreover, hedragonic acid treatment protected mice from liver injury induced by acetaminophen overdose and decreased hepatic inflammatory responses in an FXR-dependent manner, suggesting that hedragonic acid might be one of the major components of COT for its multifunctional pharmaceutical uses. In conclusion, our results provide novel structure templates for drug design based on natural triterpenes by targeting FXR and/or GPBAR1 with pharmaceutical values.

T-Probe: An Integrated Microscale Device for Online In Situ Single Cell Analysis and Metabolic Profiling Using Mass Spectrometry.

The exploration of single cells reveals cell heterogeneity and biological principle of cellular metabolism. Although a number of mass spectrometry (MS) based single cell MS (SCMS) techniques have been dedicatedly developed with high efficiency and sensitivity, limitations still exist. In this work, we introduced a microscale multifunctional device, the T-probe, which integrates cellular contents extraction and immediate ionization, to implement online in situ SCMS analysis at ambient conditions with minimal sample preparation. With high sensitivity and reproducibility, the T-probe was employed for MS analysis of single HeLa cells under control and anticancer drug treatment conditions. Intracellular species and xenobiotic metabolites were detected, and changes of cellular metabolic profiles induced by drug treatment were measured. Combining SCMS experiments with statistical data analyses, including Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA) and two-sample t-test, we provided biological insights into cellular metabolic response to drug treatment. Online MS/MS analysis was conducted at single cell level to identify species of interest, including endogenous metabolites and the drug compound. Using the T-probe SCMS technique combined with comprehensive data analyses, we provide an approach to understanding cellular metabolism and evaluate chemotherapies at the single cell level.

Structural basis for the hepatoprotective effects of antihypertensive 1,4-dihydropyridine drugs.

BACKGROUND: The 1,4-dihydropyridines (DHPs) are one of the most frequently prescribed classes of antihypertensive monotherapeutic agents worldwide. In addition to treating hypertension, DHPs also exert other beneficial effects, including hepatoprotective effects. However, the mechanism underlying the hepatoprotection remains unclear. METHODS: Biochemical AlphaScreen and cell-based reporter assays were employed to detect the activities of DHPs towards FXR. A crystallographic analysis was adopted to study the binding modes of four DHPs in complex with FXR. Acetaminophen (APAP)-treated wild-type and FXR knockout mice were used to investigate the functional dependence of the effects of the selected DHPs on FXR. RESULTS: A series of DHPs were uncovered as FXR ligands with different activities for FXR, suggesting FXR might serve as an alternative drug target for DHPs. The structural analysis illustrated the specific three-blade propeller binding modes of four DHPs to FXR and explained the detailed mechanisms by which DHPs bind to and are recognized by FXR. The results in mice demonstrated that cilnidipine protected the liver from APAP-induced injury in an FXR-dependent manner. CONCLUSIONS: This study reports the crystal structures of FXR in complex with four DHPs, and confirms that DHPs exert hepatoprotection by targeting FXR. GENERAL SIGNIFICANCE: Our research not only reveals valuable insight for the design and development of next-generation Ca2+ blocker drugs to provide safer and more effective treatments for cardiovascular disorders but also provides a novel and safe structural template for the development of drugs targeting FXR. Moreover, DHPs might be potentially repurposed to treat FXR-mediated diseases other than hypertension.

A Novel Class of Natural FXR Modulators with a Unique Mode of Selective Co-regulator Assembly.

The farnesoid X receptor (FXR) is an important target for drug discovery. Small molecules induce a conformational change in FXR that modulates its binding to co-regulators, thus resulting in distinct FXR functional profiles. However, the mechanisms for selectively recruiting co-regulators by FXR remain elusive, partly because of the lack of FXR-selective modulators. We report the identification of two natural terpenoids, tschimgine and feroline, as novel FXR modulators. Remarkably, their crystal structures uncovered a secondary binding pocket important for ligand binding. Further, tschimgine or feroline induced dynamic conformational changes in the activation function 2 (AF-2) surface, thus leading to differential co-regulator recruiting profiles, modulated by both hydrophobic and selective hydrogen-bond interactions unique to specific co-regulators. Our findings thus provide a novel structure template for optimization for FXR-selective modulators of clinical value.

One-step production of bioactive proteins through simultaneous PEGylation and refolding.

Production of protein therapeutics often involves in vitro refolding from bacterial inclusion bodies and subsequent PEGylation to improve protein stability and plasma half-life. Here, we devised a novel strategy for one-step production of site-specific mono-PEGylated proteins with good bioactivity and improved biostability by integrating PEGylation and protein refolding (IPPR). Using lysozyme and recombinant human fibroblast growth factor 21 (rhFGF21) as model proteins, we showed that both PEGylation and refolding of denatured proteins have been simultaneously accomplished by IPPR with high efficiency of refolding yield and bioconjugation. PEGylated rhFGF21 by IPPR has a similar capacity as the native rhFGF21 to stimulate glucose uptake in 3T3-L1 cells, but exhibits prolonged blood glucose and triglyceride lowering activity levels in the ob/ob diabetic mouse model. Hence, IPPR will significantly facilitate the generation of protein therapeutics.

Amlodipine metabolism in human liver microsomes and roles of CYP3A4/5 in the dihydropyridine dehydrogenation.

Amlodipine is a commonly prescribed calcium channel blocker for the treatment of hypertension and ischemic heart disease. The drug is slowly cleared in humans primarily via dehydrogenation of its dihydropyridine moiety to a pyridine derivative (M9). Results from clinical drug-drug interaction studies suggest that CYP3A4/5 mediate metabolism of amlodipine. However, attempts to identify a role of CYP3A5 in amlodipine metabolism in humans based on its pharmacokinetic differences between CYP3A5 expressers and nonexpressers failed. Objectives of this study were to determine the metabolite profile of amlodipine (a racemic mixture and S-isomer) in human liver microsomes (HLM), and to identify the cytochrome P450 (P450) enzyme(s) involved in the M9 formation. Liquid chromatography/mass spectrometry analysis showed that amlodipine was mainly converted to M9 in HLM incubation. M9 underwent further O-demethylation, O-dealkylation, and oxidative deamination to various pyridine derivatives. This observation is consistent with amlodipine metabolism in humans. Incubations of amlodipine with HLM in the presence of selective P450 inhibitors showed that both ketoconazole (an inhibitor of CYP3A4/5) and CYP3cide (an inhibitor of CYP3A4) completely blocked the M9 formation, whereas chemical inhibitors of other P450 enzymes had little effect. Furthermore, metabolism of amlodipine in expressed human P450 enzymes showed that only CYP3A4 had significant activity in amlodipine dehydrogenation. Metabolite profiles and P450 reaction phenotyping data of a racemic mixture and S-isomer of amlodipine were very similar. The results from this study suggest that CYP3A4, rather than CYP3A5, plays a key role in metabolic clearance of amlodipine in humans.