ABSTRACT
The potentiation of antibiotics is a promising strategy for combatting antibiotic-resistant/tolerant bacteria. Herein, we report that a 5-min sublethal heat shock enhances the bactericidal actions of aminoglycoside antibiotics by six orders of magnitude against both exponential- and stationary-phase Escherichia coli. This combined treatment also effectively kills various E. coli persisters, E. coli clinical isolates, and numerous gram-negative but not gram-positive bacteria and enables aminoglycosides at 5% of minimum inhibitory concentrations to eradicate multidrug-resistant pathogens Acinetobacter baumannii and Klebsiella pneumoniae. Mechanistically, the potentiation is achieved comprehensively by heat shock-enhanced proton motive force that thus promotes the bacterial uptake of aminoglycosides, as well as by increasing irreversible protein aggregation and reactive oxygen species that further augment the downstream lethality of aminoglycosides. Consistently, protonophores, chemical chaperones, antioxidants, and anaerobic culturing abolish heat shock-enhanced aminoglycoside lethality. We also demonstrate as a proof of concept that infrared irradiation- or photothermal nanosphere-induced thermal treatments potentiate aminoglycoside killing of Pseudomonas aeruginosa in a mouse acute skin wound model. Our study advances the understanding of the mechanism of actions of aminoglycosides and demonstrates a high potential for thermal ablation in curing bacterial infections when combined with aminoglycosides.
Subject(s)
Aminoglycosides , Anti-Bacterial Agents , Mice , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Aminoglycosides/pharmacology , Aminoglycosides/chemistry , Reactive Oxygen Species/pharmacology , Protein Aggregates , Escherichia coli , Gram-Negative Bacteria , Bacteria , Heat-Shock Response , Microbial Sensitivity TestsABSTRACT
Cysteine (Cys) plays an indispensable role as an antioxidant in the maintenance of bioredox homeostasis. We have constructed an efficient fluorescent probe Mito-Cys based on the binding of indole and naphthol. The acrylic ester group serves as a recognition switch for specific detection of Cys, which undergoes Michael addition and intramolecular cyclization reactions, thereby ensuring the chemical kinetics priority of Cys compared to other biothiols. The probe has good water solubility, large Stokes shift (137 nm), with a detection limit of 21.81 nM. In addition, cell imaging experiments have shown that the probe has excellent mitochondrial targeting ability (R = 0.902). The probe can distinguish between Cys, homocysteine (Hcy) and glutathione (GSH), and can detect Cys specifically and quickly (100 s) to ensure accurate quantitative analysis of Cys changes in cells. More importantly, the probe confirms that ferroptosis inducing factors trigger thiol starvation in mitochondria, which helps to gain a deeper understanding of the physiological and pathological functions related to Cys and ferroptosis.
Subject(s)
Cysteine , Fluorescent Dyes , Mitochondria , Zebrafish , Zebrafish/metabolism , Cysteine/metabolism , Cysteine/chemistry , Mitochondria/metabolism , Mitochondria/chemistry , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Humans , Animals , Indoles/chemistry , Indoles/metabolism , Optical Imaging , Molecular Structure , Naphthols/chemistry , Naphthols/chemical synthesis , Naphthols/metabolismABSTRACT
BACKGROUND: Hemorrhage is a common complication of nephrostomy and percutaneous nephrolithotripsy, and it is caused by surgical factors. Here we report a rare case of hemorrhage caused by sepsis-related coagulation dysfunction. CASE PRESENTATION: A 72-years-old male patient with bilateral ureteral calculi accompanied by hydronephrosis and renal insufficiency developed sepsis and hemorrhage on the third day after bilateral nephrostomy. After vascular injury was excluded by DSA, the hemorrhage was considered to be sepsis-associated coagulopathy(SAC/SIC), finally the patient recovered well after active symptomatic treatment. CONCLUSIONS: In patients with sepsis and hemorrhage, SAC/SIC cannot be excluded even if coagulation function is slightly abnormal after surgical factors are excluded. For urologists who may encounter similar cases in their general urology practice, it is important to be aware of these unusual causes of hemorrhage.
Subject(s)
Blood Coagulation Disorders , Nephrostomy, Percutaneous , Sepsis , Humans , Male , Aged , Sepsis/etiology , Nephrostomy, Percutaneous/adverse effects , Blood Coagulation Disorders/etiology , Postoperative Hemorrhage/etiologyABSTRACT
BACKGROUND: Gibberellins (GAs) are widely involved in plant growth and development. DELLA proteins are key regulators of plant development and a negative regulatory factor of GA. Dendrobium officinale is a valuable traditional Chinese medicine, but little is known about D. officinale DELLA proteins. Assessing the function of D. officinale DELLA proteins would provide an understanding of their roles in this orchid's development. RESULTS: In this study, the D. officinale DELLA gene family was identified. The function of DoDELLA1 was analyzed in detail. qRT-PCR analysis showed that the expression levels of all DoDELLA genes were significantly up-regulated in multiple shoots and GA3-treated leaves. DoDELLA1 and DoDELLA3 were significantly up-regulated in response to salt stress but were significantly down-regulated under drought stress. DoDELLA1 was localized in the nucleus. A strong interaction was observed between DoDELLA1 and DoMYB39 or DoMYB308, but a weak interaction with DoWAT1. CONCLUSIONS: In D. officinale, a developmental regulatory network involves a close link between DELLA and other key proteins in this orchid's life cycle. DELLA plays a crucial role in D. officinale development.
Subject(s)
Dendrobium , Dendrobium/genetics , Dendrobium/metabolism , Gibberellins/metabolism , Plant Proteins/genetics , Plant Proteins/metabolismABSTRACT
BACKGROUND AND AIMS: The mechanisms involved in liver regeneration after partial hepatectomy (pHx) are complicated. Cellular senescence, once linked to aging, plays a pivotal role in wound repair. However, the regulatory effects of cellular senescence on liver regeneration have not been fully elucidated. APPROACH AND RESULTS: Mice subjected to pHx were analyzed 14 days after surgery. The incomplete remodeling of liver sinusoids affected shear stress-induced endothelial nitric oxide synthase (eNOS) signaling on day 14, resulting in the accumulation of senescent LSECs. Removing macrophages to augment LSEC senescence led to a malfunction of the regenerating liver. A dynamic fluctuation in Notch activity accompanied senescent LSEC accumulation during liver regeneration. Endothelial Notch activation by using Cdh5-CreERT NICeCA mice triggered LSEC senescence and senescence-associated secretory phenotype, which disrupted liver regeneration. Blocking the Notch by γ-secretase inhibitor (GSI) diminished senescence and promoted LSEC expansion. Mechanically, Notch-hairy and enhancer of split 1 signaling inhibited sirtuin 1 (Sirt1) transcription by binding to its promoter region. Activation of Sirt1 by SRT1720 neutralized the up-regulation of P53, P21, and P16 caused by Notch activation and eliminated Notch-driven LSEC senescence. Finally, Sirt1 activator promoted liver regeneration by abrogating LSEC senescence and improving sinusoid remodeling. CONCLUSIONS: Shear stress-induced LSEC senescence driven by Notch interferes with liver regeneration after pHx. Sirt1 inhibition accelerates liver regeneration by abrogating Notch-driven senescence, providing a potential opportunity to target senescent cells and facilitate liver repair after injury.
Subject(s)
Cellular Senescence , Liver Regeneration , Receptors, Notch , Signal Transduction/drug effects , Sirtuin 1/metabolism , Animals , Cellular Senescence/drug effects , Cellular Senescence/physiology , Gamma Secretase Inhibitors and Modulators/pharmacology , Hepatectomy/methods , Heterocyclic Compounds, 4 or More Rings/pharmacology , Liver Regeneration/drug effects , Liver Regeneration/physiology , Mice , Nitric Oxide Synthase Type III/metabolism , Receptors, Notch/antagonists & inhibitors , Receptors, Notch/metabolism , Senescence-Associated Secretory Phenotype/geneticsABSTRACT
BACKGROUND AND AIMS: Although NASH can lead to severe clinical consequences, including cirrhosis and hepatocellular carcinoma, no effective treatment is currently available for this disease. Increasing evidence indicates that LSECs play a critical role in NASH pathogenesis; however, the mechanisms involved in LSEC-mediated NASH remain to be fully elucidated. APPROACH AND RESULTS: In the current study, we found that LSEC homeostasis was disrupted and LSEC-specific gene profiles were altered in methionine-choline-deficient (MCD) diet-induced NASH mouse models. Importantly, Notch signaling was found to be activated in LSECs of NASH mice. To then investigate the role of endothelial Notch in NASH progression, we generated mouse lines with endothelial-specific Notch intracellular domain (NICD) overexpression or RBP-J knockout to respectively activate or inhibit Notch signaling in endothelial cells. Notably, endothelial-specific overexpression of the NICD accelerated LSEC maladaptation and aggravated NASH, whereas endothelial cell-specific inhibition of Notch signaling restored LSEC homeostasis and improved NASH phenotypes. Furthermore, we demonstrated that endothelial-specific Notch activation exacerbated NASH by inhibiting endothelial nitric oxide synthase (eNOS) transcription, whereas administration of the pharmacological eNOS activator YC-1 alleviated hepatic steatosis and lipid accumulation resulting from Notch activation. Finally, to explore the therapeutic potential of using Notch inhibitors in NASH treatment, we applied two gamma-secretase inhibitors-DAPT and LY3039478-in an MCD diet-induced mouse model of NASH, and found that both inhibitors effectively ameliorated hepatic steatosis, inflammation, and liver fibrosis. CONCLUSIONS: Endothelial-specific Notch activation triggered LSEC maladaptation and exacerbated NASH phenotypes in an eNOS-dependent manner. Genetic and pharmacological inhibition of Notch signaling effectively restored LSEC homeostasis and ameliorated NASH progression.
Subject(s)
Non-alcoholic Fatty Liver Disease , Animals , Disease Models, Animal , Endothelial Cells/pathology , Endothelium , Liver/pathology , Liver Cirrhosis/complications , Methionine , Mice , Mice, Inbred C57BL , Nitric Oxide Synthase Type III , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/pathologyABSTRACT
Social recognition and memory are critical for survival. The hippocampus serves as a central neural substrate underlying the dynamic coding and transmission of social information. Yet the molecular mechanisms regulating social memory integrity in hippocampus remain unelucidated. Here we report unexpected roles of Celsr2, an atypical cadherin, in regulating hippocampal synaptic plasticity and social memory in mice. Celsr2-deficient mice exhibited defective social memory, with rather intact levels of sociability. In vivo fiber photometry recordings disclosed decreased neural activity of dorsal CA1 pyramidal neuron in Celsr2 mutants performing social memory task. Celsr2 deficiency led to selective impairment in NMDAR but not AMPAR-mediated synaptic transmission, and to neuronal hypoactivity in dorsal CA1. Those activity changes were accompanied with exuberant apical dendrites and immaturity of spines of CA1 pyramidal neurons. Strikingly, knockdown of Celsr2 in adult hippocampus recapitulated the behavioral and cellular changes observed in knockout mice. Restoring NMDAR transmission or CA1 neuronal activities rescued social memory deficits. Collectively, these results show a critical role of Celsr2 in orchestrating dorsal hippocampal NMDAR function, dendritic and spine homeostasis, and social memory in adulthood.
ABSTRACT
Melasma is a common, relapsing, multifactorial disease for which the treatment decision remains extremely difficult. This study was designed to compare the efficacy and safety of the combination of tranexamic acid (TA) injection and electro-optical synergy (ELOS) versus TA injection alone in treating melasma. A retrospective study was undertaken for patients with facial epidermal or mixed-type melasma to compare clinical data between 15 patients receiving a combination regimen and 15 patients with TA injection only. The study administered TA through intravenous injection to the combination group (twice weekly for 12 weeks) followed by ELOS therapy (once a month for three times). The TA group, on the other hand, received only TA injection (twice weekly for 12 weeks). The evaluation of clinical effectiveness was based on comparing the Melasma Area Severity Index (MASI) scores before and one month after treatment (at 4 months). The Physician Global Assessment (PGA) and Patient satisfaction were documented, and adverse reactions were recorded. All patients were followed up for one year to observe the relapse. After treatment, the MASI scores and melasma severity were significantly reduced in both groups. The combination group showed better efficacy than the TA only group (P < 0.05). The Physician Global Assessment (PGA) and Patient satisfaction showed superior efficacies of the combination group. No significant difference was observed between the two groups in terms of treatment-related side effects. Both groups experienced a certain degree of recurrence during the one-year follow-up, but the TA only group had a significantly higher recurrence rate than the combination group (P < 0.01). Together, the combination of TA injection and ELOS is a safe and effective treatment strategy for melasma and should be promoted.
Subject(s)
Melanosis , Tranexamic Acid , Humans , Tranexamic Acid/adverse effects , Retrospective Studies , Treatment Outcome , Patient Satisfaction , Melanosis/drug therapyABSTRACT
The APETALA2 (AP2) transcription factors (TFs) play crucial roles in regulating development in plants. However, a comprehensive analysis of the AP2 family members in a valuable Chinese herbal orchid, Dendrobium officinale, or in other orchids, is limited. In this study, the 14 DoAP2 TFs that were identified from the D. officinale genome and named DoAP2-1 to DoAP2-14 were divided into three clades: euAP2, euANT, and basalANT. The promoters of all DoAP2 genes contained cis-regulatory elements related to plant development and also responsive to plant hormones and stress. qRT-PCR analysis showed the abundant expression of DoAP2-2, DoAP2-5, DoAP2-7, DoAP2-8 and DoAP2-12 genes in protocorm-like bodies (PLBs), while DoAP2-3, DoAP2-4, DoAP2-6, DoAP2-9, DoAP2-10 and DoAP2-11 expression was strong in plantlets. In addition, the expression of some DoAP2 genes was down-regulated during flower development. These results suggest that DoAP2 genes may play roles in plant regeneration and flower development in D. officinale. Four DoAP2 genes (DoAP2-1 from euAP2, DoAP2-2 from euANT, and DoAP2-6 and DoAP2-11 from basal ANT) were selected for further analyses. The transcriptional activation of DoAP2-1, DoAP2-2, DoAP2-6 and DoAP2-11 proteins, which were localized in the nucleus of Arabidopsis thaliana mesophyll protoplasts, was further analyzed by a dual-luciferase reporter gene system in Nicotiana benthamiana leaves. Our data showed that pBD-DoAP2-1, pBD-DoAP2-2, pBD-DoAP2-6 and pBD-DoAP2-11 significantly repressed the expression of the LUC reporter compared with the negative control (pBD), suggesting that these DoAP2 proteins may act as transcriptional repressors in the nucleus of plant cells. Our findings on AP2 genes in D. officinale shed light on the function of AP2 genes in this orchid and other plant species.
Subject(s)
Dendrobium/genetics , Plant Proteins/genetics , Transcription Factors/genetics , Dendrobium/growth & development , Gene Expression Regulation, Plant , Genome-Wide Association Study , Multigene Family , Phylogeny , Plant Leaves/genetics , Plant Proteins/metabolism , Plants, Genetically Modified , Promoter Regions, Genetic , Protein Interaction Maps , Regulatory Sequences, Nucleic Acid , Stress, Physiological/genetics , Nicotiana/genetics , Transcription Factors/metabolismABSTRACT
In this study, we investigated the effects of isorhamnetin on myocardial ischaemia reperfusion (I/R) injury in Langendorff-perfused rat hearts. Isorhamnetin treatment (5, 10 and 20 µg/mL) significantly alleviated cardiac morphological injury, reduced myocardial infarct size, decreased the levels of marker enzymes (LDH and CK) and improved the haemodynamic parameters, reflected by the elevated levels of the left ventricular developed pressure (LVDP), coronary flow (CF) and the maximum up/down velocity of left ventricular pressure (+dp/dtmax ). Moreover, isorhamnetin reperfusion inhibited apoptosis of cardiomyocytes in the rats subjected to cardiac I/R in a dose-dependent manner concomitant with decreased protein expression of Bax and cleaved-caspase-3, as well as increased protein expression of Bcl-2. In addition, I/R-induced oxidative stress was manifestly mitigated by isorhamnetin treatment, as showed by the decreased malondialdehyde (MDA) level and increased antioxidant enzymes activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). These results indicated that isorhamnetin exerts a protective effect against I/R-induced myocardial injury through the attenuation of apoptosis and oxidative stress.
Subject(s)
Apoptosis , Cardiotonic Agents/therapeutic use , Myocardial Reperfusion Injury/drug therapy , Myocardium/pathology , Quercetin/analogs & derivatives , Animals , Apoptosis/drug effects , Cardiotonic Agents/pharmacology , Caspase 3/metabolism , Male , Myocardial Infarction/drug therapy , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Myocardial Reperfusion Injury/physiopathology , Myocardium/enzymology , Oxidative Stress/drug effects , Quercetin/pharmacology , Quercetin/therapeutic use , Rats , Rats, Sprague-Dawley , bcl-2-Associated X Protein/metabolismABSTRACT
Liver sinusoidal endothelial cells (LSECs) critically regulate liver homeostasis and diseases through angiocrine factors. Notch is critical in endothelial cells (ECs). In the current study, Notch signaling was activated by inducible EC-specific expression of the Notch intracellular domain (NIC). We found that endothelial Notch activation damaged liver homeostasis. Notch activation resulted in decreased fenestration and increased basement membrane, and a gene expression profile with decreased LSEC-associated genes and increased continuous EC-associated genes, suggesting LSEC dedifferentiation. Consistently, endothelial Notch activation enhanced hepatic fibrosis (HF) induced by CCl4 . Notch activation attenuated endothelial nitric oxide synthase (eNOS)/soluble guanylate cyclase (sGC) signaling, and activation of sGC by 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1) reversed the dedifferentiation phenotype. In addition, Notch activation subverted the hepatocyte-supporting angiocrine profile of LSECs by down-regulating critical hepatocyte mitogens, including Wnt2a, Wnt9b, and hepatocyte growth factor (HGF). This led to compromised hepatocyte proliferation under both quiescent and regenerating conditions. Whereas expression of Wnt2a and Wnt9b was dependent on eNOS-sGC signaling, HGF expression was not rescued by the sGC activator, suggesting heterogeneous mechanisms of LSECs to maintain hepatocyte homeostasis. CONCLUSION: Endothelial Notch activation results in LSEC dedifferentiation and accelerated liver fibrogenesis through eNOS-sGC signaling, and alters the angiocrine profile of LSECs to compromise hepatocyte proliferation and liver regeneration (LR). (Hepatology 2018).
Subject(s)
Endothelial Cells/metabolism , Hepatocytes/metabolism , Liver Cirrhosis/metabolism , Liver Regeneration/genetics , Receptors, Notch/metabolism , Animals , Blotting, Western , Cell Culture Techniques , Cell Proliferation , Endothelial Cells/pathology , Enzyme-Linked Immunosorbent Assay , Gene Expression Profiling , Liver/metabolism , Liver/pathology , Liver Regeneration/physiology , Male , Mice , Mice, Inbred C57BL , Real-Time Polymerase Chain Reaction , Signal Transduction/geneticsABSTRACT
Optical surgical navigation system has been a hot research topic because of its high accuracy. This paper focuses on identifying and tracking multiple surgical instruments to meet the requirements of applying multiple surgical instruments in clinical medicine. The methods of instrument identification based on the marker's geometrical arrangement and instrument tracking based on markers' motion vector were applied in the proposed algorithm. The experiments of multiple instruments' identification and tracking, the instruments' stability, the space distance and rotation of a pair of instruments at the same tracking time were performed to verify the proposed algorithm. The stereoscopic camera is applied to capture images, and two 850 nm filters are added in front of the binocular camera. The tracking experiment shows that ten instruments can be fully and accurately identified, and then all of them can be quickly and accurately tracked at the same time. A pair of instruments is simultaneously measured in the stability test, such as the typical surgical instrument (TSI) and the miniature surgical instrument (MSI). The ranges of standard deviations (SD) of the stability test for the TSI in the X-, Y-, and Z- axes are from 0.016 mm to 0.127 mm, from 0.011 mm to 0.090 mm, and from 0.124 mm to 0.901 mm, respectively. And the ranges of SDs for the MSI's stability test are from 0.011 mm to 0.133 mm in the X-axis, from 0.010 mm to 0.106 mm in the Y-axis, and from 0.093 mm to 0.932 mm in the Z-axis. The sub-millimeter SDs show that the proposed algorithm has a high stability. Moreover, the space distance test and the rotation test were performed for simultaneously tracking TSI and MSI. All experimental results indicate the proposed algorithm is able to meet the clinical accuracy requirements.
ABSTRACT
Over-activation of beta-catenin/TCF signaling is very common in the progression of hepatocellular carcinoma (HCC). The molecular mechanisms leading to the aberrant activation of beta-catenin/TCF signaling are not fully understood. In this study, it was found that CDK7 was up-regulated in HCC tissues and its expression inversely correlated with the survival of HCC patients. Functional study showed that CDK7 promoted the growth and migration of HCC cells, and knocking down the expression of CDK7 inhibited the growth of HCC cells in both liquid culture and soft agar. Mechanistically, CDK7 interacted with beta-catenin, enhanced the interaction between beta-catenin and TCF4, and activated beta-catenin/TCF signaling. Taken together, this study demonstrated the oncogenic roles of CDK7 in HCC and suggested that CDK7 might be a promising therapeutic target.
Subject(s)
Carcinoma, Hepatocellular/metabolism , Cyclin-Dependent Kinases/metabolism , Liver Neoplasms/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Movement/physiology , Cell Proliferation/physiology , Gene Expression Regulation, Neoplastic/genetics , Humans , Liver Neoplasms/pathology , Signal Transduction/physiology , TCF Transcription Factors/metabolism , beta Catenin/metabolism , Cyclin-Dependent Kinase-Activating KinaseABSTRACT
Objective To explore the effects of cathepsin B(CTSB)on the activation of nucleotide-binding domain and leucine-rich-repeat-containing family and pyrin domain-containing 3(NLRP3)inflammasome via transient receptor potential mucolipin-1(TRPML1)in cell oxidative stress model and specific gene silencing cell model. Methods BV2 cells cultured in vivo were treated separately or simultaneously with hydrogen peroxide(H2O2),calcium-sensitive receptor agonist gadolinium trichloride(GdCl3),and CTSB inhibitor CA-074Me,and interleukin-1(IL-1)beta and caspase-1 protein were detected by enzyme-linked immunosorbent assay.The growth activity of BV2 cells in each group was measured by MTT.BV2 cells were treated with different concentrations of H2O2.Cystatin C mRNA and TRPML1 mRNA in BV2 cells were detected by real-time quantitative polymerase chain reaction and the proteins of TRPML1,CTSB,cathepsin D(CTSD),cathepsin L(CTSL)and cathepsin V(CTSV)were detected by Western blot.Specific small interfering RNA was designed for TRPML1 gene target sequence.TRPML1 gene silencing cell lines(named Tr-si-Bv2 cells)were established in BV2 cells and treated with or without H2O2.TRPML1,CTSB and transcription factor EB(TFEB)proteins in Tr-si-Bv2 cells or control cells were detected by Western blot. Results After treatment with H2O2,the expression of caspase-1 protein and NLRP3 mRNA in BV2 cells was increased,and IL-1beta protein in BV2 cells was significantly increased after treatment with GdCl3(P=0.0036).After treatment with CA-074Me,the doses of NLRP3 mRNA(P=0.037),caspase-1(P=0.021),and IL-1ß(P= 0.036)were significantly reduced.Cells in the H2O2 group and H2O2+GdCl3 group grew more slowly.The expressions of CTSB mRNA and TRPML1 mRNA,or CTSB and TRPML1 proteins in BV2 cells in the treatment group with 200 µmol/L of H2O2 concentration were similar.H2O2-induced CTSB protein expression was inhibited after silencing TRPML1 gene.The changes of other cathepsins were not affected for the different concentration of H2O2.In the BV2 cells treated with TRPML1 gene silencing,the expression of CTSB protein was significantly reduced and the difference was statistically significant(P=0.021)between the H2O2 +siRNA treatment group and the H2O2 treatment group.Conclusion CTSB regulates the activation of NLRP3 inflammasome in the oxidative stress model of microglia cells,probably mediated by calcium channel protein TRPML1.
Subject(s)
Cathepsin B/metabolism , Inflammasomes/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Oxidative Stress , Transient Receptor Potential Channels/metabolism , Animals , Cathepsin B/antagonists & inhibitors , Cell Line , Gene Silencing , Hydrogen Peroxide , Interleukin-1beta , Mice , Microglia , Pyrin DomainABSTRACT
The mechanism of substrate hydrolysis of New Delhi metallo-ß-lactamase 1 (NDM-1) has been reported, but the process in which NDM-1 captures and transports the substrate into its active center remains unknown. In this study, we investigated the process of the substrate entry into the NDM-1 activity center through long unguided molecular dynamics simulations using meropenem as the substrate. A total of 550 individual simulations were performed, each of which for 200 ns, and 110 of them showed enzyme-substrate binding events. The results reveal three categories of relatively persistent and noteworthy enzyme-substrate binding configurations, which we call configurations A, B, and C. We performed binding free energy calculations of the enzyme-substrate complexes of different configurations using the molecular mechanics Poisson-Boltzmann surface area method. The role of each residue of the active site in binding the substrate was investigated using energy decomposition analysis. The simulated trajectories provide a continuous atomic-level view of the entire binding process, revealing potentially valuable regions where the enzyme and the substrate interact persistently and five possible pathways of the substrate entering into the active center, which were validated using well-tempered metadynamics. These findings provide important insights into the binding mechanism of meropenem to NDM-1, which may provide new prospects for the design of novel metallo-ß-lactamase inhibitors and enzyme-resistant antibiotics.
Subject(s)
Molecular Dynamics Simulation , Thienamycins/metabolism , beta-Lactamases/metabolism , Binding Sites , Catalytic Domain , Meropenem , Protein Binding , Substrate Specificity , Thermodynamics , Thienamycins/chemistry , beta-Lactamases/chemistryABSTRACT
To study the differences and similarities in pharmaceutical characterization and pharmacodynamic characterization between the single decoction and merger decoction of Baihu and Guizhi. The same technology parameters were used to prepare Baihu and Guizhi single decoticon and merger decoction extracts, and then the differences and similarities in pharmaceutical characterization were analyzed based on their HPLC fingerprint, content of index components, and the extraction content. The pharmacodynamic differences and similarities were analyzed by inflammatory model and pain model. There was no significant difference in HPLC chromatographic peak, but the peak area value reflected the difference of quantity to some extent. It was found that the peak value of single Rhizoma anemarrhenae and Cassia twig decoction was less than the peak of their merger decoction, but the peak value of single honey-fried Licorice root decoction was greater than the peak of merger decoctionï¼ The contents of neomangiferin, mangiferin and timosaponin B â ¡ among index components as well as extraction content in merger decoction were higher than those in single decoctionï¼ The contents of liquiritin and glycyrrhizic acid as well as extraction content in merger decoction were lower than those in single decoctionï¼ There was no significant difference in the content of cinnamicacid and its extraction content between merger decoction and single decoction. According to the efficacy experiment, both of them showed significant anti-inflammatory and analgesic effects. However, the merger decoction showed faster anti-inflammation effect, and longer analgesic effect. It can be concluded that the merger decoction and single decoction of Baihu and Guizhi have the same material basis, and the merger decoction is better for the dissolution of the active ingredients in this recipe, and is more beneficial to the therapeutic effect.
Subject(s)
Cinnamomum aromaticum/chemistry , Drugs, Chinese Herbal/chemistry , Anemarrhena/chemistry , Cassia/chemistry , Chromatography, High Pressure Liquid , Glycyrrhiza/chemistry , Rhizome/chemistryABSTRACT
Although it has been suggested that Dll3, one of the Notch ligands, promotes the proliferation and inhibits the apoptosis of cancer cells, the role of Dll3 in cancers remains unclear. In this study, we found that in the murine Lewis lung carcinoma (LLC) cells, the level of Dll3 mRNA changed upon tumor microenvironment (TME) stimulation, namely, decreased under hypoxia or stimulated with tumor necrosis factor (TNF)-α. Dll3 was also expressed at higher level in human lung carcinoma tissues than in the para-carcinoma tissues. Overexpression of Dll3 in LLC cells promoted cell proliferation and reduced apoptosis in vitro, and enhanced tumor growth when inoculated in vivo in mice. The Dll3-mediated proliferation could be due to increased Akt phosphorylation in LLC cells, because an Akt inhibitor counteracted Dll3-induced proliferation. Moreover, Dll3 overexpression promoted PI3K/Akt signaling through inhibiting Notch signaling.
Subject(s)
Carcinoma, Lewis Lung/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Lung Neoplasms/metabolism , Membrane Proteins/metabolism , Receptors, Notch/metabolism , Animals , Carcinoma, Lewis Lung/pathology , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Hypoxia , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Intracellular Signaling Peptides and Proteins/genetics , Lung Neoplasms/pathology , Membrane Proteins/genetics , Mice, Inbred C57BL , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Tumor Cells, Cultured , Tumor Microenvironment/drug effects , Tumor Necrosis Factor-alpha/pharmacology , Xenograft Model Antitumor AssaysABSTRACT
AIM: To investigate the embryotoxicity of dihydroartemisinin (DHA), the main active metabolite of artemisinin, in zebrafish, and explore the corresponding mechanisms. METHODS: The embryos of wild type and TG (flk1:GFP) transgenic zebrafish were exposed to DHA. Developmental phenotypes of the embryos were observed. Development of blood vessels was directly observed in living embryos of TG (flk1:GFP) transgenic zebrafish under fluorescence microscope. The expression of angiogenesis marker genes vegfa, flk1, and flt1 in the embryos was detected using real-time PCR and RNA in situ hybridization assays. RESULTS: Exposure to DHA (1-10 mg/L) dose-dependently caused abnormal zebrafish embryonic phenotypes in the early developmental stage. Furthermore, exposure to DHA (10 mg/L) resulted in more pronounced embryonic angiogenesis in TG (flk1:GFP) zebrafish line. Exposure to DHA (10 mg/L) significantly increased the mRNA expression of vegfa, flk1, and flt1 in the embryos. Knockdown of the flk1 protein partially blocked the effects of DHA on embryogenesis. CONCLUSION: DHA causes abnormal embryonic phenotypes and promotes angiogenesis in zebrafish early embryonic development, demonstrating the potential embryotoxicity of DHA.
Subject(s)
Artemisia/toxicity , Artemisinins/toxicity , Embryo, Nonmammalian/drug effects , Embryo, Nonmammalian/embryology , Neovascularization, Pathologic/chemically induced , Zebrafish/embryology , Animals , Animals, Genetically Modified , Embryo, Nonmammalian/pathology , Embryonic Development/drug effects , Embryonic Development/physiology , Neovascularization, Pathologic/pathology , Zebrafish/geneticsABSTRACT
OBJECTIVE: To evaluate the safety, effectiveness, and outcomes of holmium laser enucleation of the prostate (HoLEP) for patients with symptomatic enlarged prostate after 11 years of experience. METHODS: The 3162 evaluable patients treated with holmium laser enucleation of the prostate at our institution between August 2001 and August 2011 were retrospectively analyzed. Study variables included International Prostate Symptom Score, quality of life, maximum urinary flow rate, and incidence of complications. RESULTS: HoLEP were performed successfully completed, not patients which occurs as electric cutting syndrome. The operation time was (60.8 ± 18.4) minutes; average resection of prostate quality was (45.4 ± 24.4) g. The hemoglobin reduce though surgery was (1.81 ± 0.93) g/L; percentage of red blood cell change was 1.24% ± 0.43%, and sodium blood drop was (1.14 ± 0.35) mmol/L. Postoperative patients of hospital stay (3.1 ± 1.1) days, average time of indwelling catheter time was (2.3 ± 0.8) days. Patients were followed up for 6-131 months time, an average of 32.4 months. Postoperative patients with international prostate symptom score progressive declined. The quality of life score was 2.2 ± 1.7, and it less than preoperative (5.7 ± 3.3, t = 2.447, P < 0.01). The time of follow-up droped further, and postoperative comparative differences have statistical significance (t = 2.179, 2.228, 2.306 and 2.365, P < 0.05). The maximum urinary flow rate also improved (P < 0.05). Postoperative complications included bladder neck contracture (4 cases), urinary tract infection (107 cases), urethral stricture (11 cases) and urinary incontinence (11 cases). The 11 patients reoperation. CONCLUSIONS: HoLEP treatment of benign prostatic hyperplasia could achieve the advantages of open surgery the same effect. It had fewer damage, faster recovery, fewer complications, and is a good treatment option.