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Oxidative Medicine and Cellular... 2021Vinegar is good for health. Tetramethylpyrazine (TMP) is the main component of its flavor, quality, and function. We hypothesized that vinegar/TMP pretreatment could...
Vinegar is good for health. Tetramethylpyrazine (TMP) is the main component of its flavor, quality, and function. We hypothesized that vinegar/TMP pretreatment could induce myocardial protection of "nutritional preconditioning (NPC)" by low-dose, long-term supplementation and alleviate the myocardial injury caused by anoxia/reoxygenation (A/R). To test this hypothesis, TMP content in vinegar was detected by HPLC; A/R injury model was prepared by an isolated mouse heart and rat cardiomyocyte to evaluate the myocardial protection and mechanism of vinegar/TMP pretreatment by many enzymatic or functional, or cellular and molecular biological indexes. Our results showed that vinegar contained TMP, and its content was in direct proportion to storage time. Vinegar/TMP pretreatment could improve hemodynamic parameters, decrease lactate dehydrogenase (LDH) and creatine phosphokinase activities, and reduce infarct size and apoptosis in the isolated hearts of mice with A/R injury. Similarly, vinegar/TMP pretreatment could increase cell viability, decrease LDH activity, and decrease apoptosis against A/R injury of cardiomyocytes. Vinegar/TMP pretreatment could also maintain the mitochondrial function of A/R-injured cardiomyocytes, including improving oxygen consumption rate and extracellular acidification rate, reducing reactive oxygen species generation, mitochondrial membrane potential loss, mitochondrial permeability transition pore openness, and cytochrome c releasing. However, the protective effects of vinegar/TMP pretreatment were accompanied by the downregulation of VDAC1 expression in the myocardium and reversed by pAD/VDAC1, an adenovirus that upregulates VDAC1 expression. In conclusion, this study is the first to demonstrate that vinegar/TMP pretreatment could induce myocardial protection of NPC due to downregulating VDAC1 expression, inhibiting oxidative stress, and preventing mitochondrial dysfunction; that is, VDAC1 is their target, and the mitochondria are their target organelles. TMP is one of the most important myocardial protective substances in vinegar.
Topics: Acetic Acid; Animals; Cardiovascular Diseases; Humans; Male; Mice; Myocardium; Nutrition Assessment; Pyrazines; Rats; Voltage-Dependent Anion Channel 1
PubMed: 33995824
DOI: 10.1155/2021/6670088 -
Molecular Cancer Therapeutics Nov 2021Acute myeloid leukemia (AML) with an internal tandem duplication (-ITD) mutation is an aggressive hematologic malignancy associated with frequent relapse and poor...
Acute myeloid leukemia (AML) with an internal tandem duplication (-ITD) mutation is an aggressive hematologic malignancy associated with frequent relapse and poor overall survival. The tyrosine kinase inhibitor gilteritinib is approved for the treatment of relapse/refractory AML with mutations, yet its mechanism of action is not completely understood. Here, we sought to identify additional therapeutic targets that can be exploited to enhance gilteritinib's antileukemic effect. Based on unbiased transcriptomic analyses, we identified the glutamine transporter SNAT1 (SLC38A1) as a novel target of gilteritinib that leads to impaired glutamine uptake and utilization within leukemic cells. Using metabolomics and metabolic flux analyses, we found that gilteritinib decreased glutamine metabolism through the TCA cycle and cellular levels of the oncometabolite 2-hydroxyglutarate. In addition, gilteritinib treatment was associated with decreased ATP production and glutathione synthesis and increased reactive oxygen species, resulting in cellular senescence. Finally, we found that the glutaminase inhibitor CB-839 enhanced antileukemic effect of gilteritinib in studies using human primary -ITD-positive AML cells harboring mutations in the enzyme isocitrate dehydrogenase, which catalyzes the oxidative decarboxylation of isocitrate, producing α-ketoglutarate. Collectively, this work has identified a previously unrecognized, gilteritinib-sensitive metabolic pathway downstream of SLC38A1 that causes decreased glutaminolysis and disruption of redox homeostasis. These findings provide a rationale for the development and therapeutic exploration of targeted combinatorial treatment strategies for this subset of relapse/refractory AML.
Topics: Aniline Compounds; Animals; Female; Glutamine; Humans; Leukemia, Myeloid, Acute; Mice; Pyrazines; fms-Like Tyrosine Kinase 3
PubMed: 34518298
DOI: 10.1158/1535-7163.MCT-21-0071 -
The Journal of Antibiotics Aug 2016Photorhabdus luminescens is a bioluminescent entomopathogenic bacterium that undergoes phenotypic variation and lives in mutualistic association with nematodes of the...
Photorhabdus luminescens is a bioluminescent entomopathogenic bacterium that undergoes phenotypic variation and lives in mutualistic association with nematodes of the family Heterorhabditidae. The pair infects and kills insects, and during their coordinated lifecycle, the bacteria produce an assortment of specialized metabolites to regulate its mutualistic and pathogenic roles. As part of our search for new specialized metabolites from the Photorhabdus genus, we examined organic extracts from P. luminescens grown in an amino-acid-rich medium based on the free amino-acid levels found in the circulatory fluid of its common insect prey, the Galleria mellonella larva. Reversed-phase HPLC/UV/MS-guided fractionation of the culture extracts led to the identification of two new pyrazinone metabolites, lumizinones A (1) and B (2), together with two N-acetyl dipeptides (3 and 4). The lumizinones were produced only in the phenotypic variant associated with nematode development and insect pathogenesis. Their chemical structures were elucidated by analysis of 1D and 2D NMR and high-resolution ESI-QTOF-MS spectral data. The absolute configurations of the amino acids in 3 and 4 were determined by Marfey's analysis. Compounds 1-4 were evaluated for their calpain protease inhibitory activity, and lumizinone A (1) showed inhibition with an IC50 (half-maximal inhibitory concentration) value of 3.9 μm.
Topics: Amino Acids; Animals; Chromatography, High Pressure Liquid; Inhibitory Concentration 50; Lepidoptera; Magnetic Resonance Spectroscopy; Mass Spectrometry; Photorhabdus; Protease Inhibitors; Pyrazines; Spectrometry, Mass, Electrospray Ionization
PubMed: 27353165
DOI: 10.1038/ja.2016.79 -
Theranostics 2022Immunogenic cell death (ICD)-associated immunogenicity evoked through reactive oxygen species (ROS) is an efficient way to fight against the immune-dysfunctional...
Immunogenic cell death (ICD)-associated immunogenicity evoked through reactive oxygen species (ROS) is an efficient way to fight against the immune-dysfunctional microenvironment, so as to provoke potent anti-tumor immunity. However, the unknown ROS dose during cancer therapies may induce adverse immune responses (e.g., insufficient ICD, toxicity toward normal tissues or immune system). Herein, we developed a pyrido pyrazine - thiophene based semiconducting polymer as novel near-infrared (NIR) organic afterglow nanoparticles for the real-time visualization of self-generated ROS, during photodynamic-mediated immunogenic cell death. Specifically, we introduced the strong "acceptor" (pyrido pyrazine) into thiophene based semiconducting polymer to redshift emission wavelength, and further modulate the "donor" to afford more afterglow reaction sites and reducing ΔEst, so as to enhance luminescence intensity. The semiconducting polymer-based afterglow nanoparticles exhibit strong afterglow emission with longer-wavelength emission (> 800 nm), compared with the reported organic afterglow nanoparticles (e.g., MEHPPV, PFODBT or Chlorin, < 690 nm), which endows this afterglow nanoparticles with a greatly improvement of signal to noise ratio. Moreover, the photodynamic effect of this afterglow nanoparticles can induce immunogenic cell death of cancer cells and further cause immune responses in mice. The NIR afterglow signal presents a good relationship with ROS generation, immunogenic cell death and outcome of treatment. Therefore, it was able to provide a non-invasive tool for predicting the degree of ICD that occurs during ROS-mediated cancer therapy and may contribute to precise immunotherapy.
Topics: Mice; Animals; Reactive Oxygen Species; Nanoparticles; Polymers; Thiophenes; Pyrazines; Cell Line, Tumor; Neoplasms
PubMed: 36276646
DOI: 10.7150/thno.77457 -
The Lancet. Respiratory Medicine May 2023
Topics: Humans; Amides; Antiviral Agents; COVID-19; Pyrazines; Treatment Outcome
PubMed: 36528037
DOI: 10.1016/S2213-2600(22)00479-9 -
Molecules (Basel, Switzerland) May 2015A series of N-alkyl-3-(alkylamino)pyrazine-2-carboxamides and their N-alkyl-3-chloropyrazine-2-carboxamide precursors were prepared. All compounds were characterized by...
A series of N-alkyl-3-(alkylamino)pyrazine-2-carboxamides and their N-alkyl-3-chloropyrazine-2-carboxamide precursors were prepared. All compounds were characterized by analytical methods and tested for antimicrobial and antiviral activity. The antimycobacterial MIC values against Mycobacterium tuberculosis H37Rv of the most effective compounds, 3-(hexylamino)-, 3-(heptylamino)- and 3-(octylamino)-N-methyl-pyrazine-2-carboxamides 14‒16, was 25 μg/mL. The compounds inhibited photosystem 2 photosynthetic electron transport (PET) in spinach chloroplasts. This activity was strongly connected with the lipophilicity of the compounds. For effective PET inhibition longer alkyl chains in the 3-(alkylamino) substituent in the N-alkyl-3-(alkylamino)pyrazine-2-carboxamide molecule were more favourable than two shorter alkyl chains.
Topics: Antitubercular Agents; Bacterial Proteins; Chloroplasts; Electron Transport; Fatty Acid Synthases; Microbial Sensitivity Tests; Mycobacterium tuberculosis; Pyrazinamide; Pyrazines; Spinacia oleracea; Structure-Activity Relationship
PubMed: 26007174
DOI: 10.3390/molecules20058687 -
Sensors (Basel, Switzerland) Dec 2018Developing a controlled method for obtaining hybrid enzymatic-based interfaces for sensing application require the use of a multiuse, reusable sensor. By controlling the...
Developing a controlled method for obtaining hybrid enzymatic-based interfaces for sensing application require the use of a multiuse, reusable sensor. By controlling the interface characteristics in terms of the surface chemistry, thickness, and roughness, a tailored response toward various toxic compounds can be obtained, regarding both materials used as active surfaces and fabrication methods. Herein, we report a preliminary study on using a laser-based method (i.e., matrix-assisted pulsed laser evaporation, or MAPLE) for obtaining active polymeric⁻enzymatic interfaces as hybrid or layered coatings for detecting toxic vapors. The MAPLE fabrication consisted of the simultaneous alternating evaporation of layers of polyethylenimine (PEI) and acetylcholinesterase (AchE) in order to obtain active surfaces as both hybrid PEI-AchE and a PEI/AchE layered coating, respectively. The deposition processes of the polymer and enzyme were carried out using a double-target system and a Nd:YAG pulsed laser, operating at 0.45 J/cm² fluences with a wavelength of 266 nm and a repetition rate of 10 Hz. Fourier transform infrared spectroscopy revealed no significant changes in the functional groups of both hybrid and layered coatings compared with the initial material. The thickness and roughness, as well as the morphologies of the coatings revealed by atomic force microscopy and scanning electron microscopy showed coatings thicker than two μm that had smooth surfaces and average roughness values below six nm. The sensors were tested with simulants for nerve gases and pesticides containing phosphonate ester groups, namely dimethyl methylphosphonate (DMMP) and diisopropyl methylphosphonate (DIMP), and a different sensitivity was shown to the selected chemical agents for each of the sensors. The best sensitivities for DMMP and DIMP obtained by using a PEI-AchE coated sensor are 65 kHz and 200 kHz, respectively, whereas the best sensitivity when using multilayered interfaces is 30 kHz and 10 KHz for DIMP and DMMP, respectively.
Topics: Acetylcholinesterase; Biosensing Techniques; Gases; Organophosphorus Compounds; Polyethyleneimine; Pyrazines
PubMed: 30518102
DOI: 10.3390/s18124265 -
Animal Models and Experimental Medicine Feb 2024The maintenance dosage of selexipag is categorized as low, medium or high. In order to assess the efficacy and safety of different dosages of selexipag for the risk... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The maintenance dosage of selexipag is categorized as low, medium or high. In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypertension (PAH), we performed a systematic review and meta-analysis.
METHODS
Studies assessing PAH risk stratification indices, such as the World Health Organization functional class (WHO-FC), six-minute walk distance (6MWD), N-terminal pro-B-type natriuretic peptide (NT-proBNP) level, right atrial pressure (RAP), cardiac index (CI) and mixed venous oxygen saturation (SvO), were included.
RESULTS
Thirteen studies were included. Selexipag led to improvements in the 6MWD (MD: 24.20 m, 95% CI: 10.74-37.67), NT-proBNP (SMD: -0.41, 95% CI: -0.79-0.04), CI (MD: 0.47 L/min/m, 95% CI: 0.17-0.77) and WHO-FC (OR: 0.564, 95% CI: 0.457-0.697). Subgroup analysis demonstrated that all three dosages improved the 6MWD. A moderate dosage led to improvements in the CI (MD: 0.30 L/min/m, 95% CI: 0.15-0.46) and WHO-FC (OR: 0.589, 95% CI: 0.376-0.922). Within 6 months of treatment, only the WHO-FC and CI were significantly improved (OR: 0.614, 95% CI: 0.380-0.993; MD: 0.30 L/min/m, 95% CI: 0.16-0.45, respectively). More than 6 months of treatment significantly improved the 6MWD, WHO-FC and NT-proBNP (MD: 40.87 m, 95% CI: 10.97-70.77; OR: 0.557, 95% CI: 0.440-0.705; SMD: -0.61, 95% CI: -1.17-0.05, respectively).
CONCLUSIONS
Low, medium, and high dosages of selexipag all exhibited good effects. When treatment lasted for more than 6 months, selexipag exerted obvious effects, even in the low-dosage group. This finding is important for guiding individualized treatments.
Topics: Humans; Hypertension, Pulmonary; Pulmonary Arterial Hypertension; Acetamides; Pyrazines
PubMed: 37740617
DOI: 10.1002/ame2.12347 -
The New England Journal of Medicine Mar 2015The proteasome inhibitor bortezomib was initially approved for the treatment of relapsed mantle-cell lymphoma. We investigated whether substituting bortezomib for... (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND
The proteasome inhibitor bortezomib was initially approved for the treatment of relapsed mantle-cell lymphoma. We investigated whether substituting bortezomib for vincristine in frontline therapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) could improve outcomes in patients with newly diagnosed mantle-cell lymphoma.
METHODS
In this phase 3 trial, we randomly assigned 487 adults with newly diagnosed mantle-cell lymphoma who were ineligible or not considered for stem-cell transplantation to receive six to eight 21-day cycles of R-CHOP intravenously on day 1 (with prednisone administered orally on days 1 to 5) or VR-CAP (R-CHOP regimen, but replacing vincristine with bortezomib at a dose of 1.3 mg per square meter of body-surface area on days 1, 4, 8, and 11). The primary end point was progression-free survival.
RESULTS
After a median follow-up of 40 months, median progression-free survival (according to independent radiologic review) was 14.4 months in the R-CHOP group versus 24.7 months in the VR-CAP group (hazard ratio favoring the VR-CAP group, 0.63; P<0.001), a relative improvement of 59%. On the basis of investigator assessment, the median durations of progression-free survival were 16.1 months and 30.7 months, respectively (hazard ratio, 0.51; P<0.001), a relative improvement of 96%. Secondary end points were consistently improved in the VR-CAP group, including the complete response rate (42% vs. 53%), the median duration of complete response (18.0 months vs. 42.1 months), the median treatment-free interval (20.5 months vs. 40.6 months), and the 4-year overall survival rate (54% vs. 64%). Rates of neutropenia and thrombocytopenia were higher in the VR-CAP group.
CONCLUSIONS
VR-CAP was more effective than R-CHOP in patients with newly diagnosed mantle-cell lymphoma but at the cost of increased hematologic toxicity. (Funded by Janssen Research and Development and Millennium Pharmaceuticals; LYM-3002 ClinicalTrials.gov number, NCT00722137.).
Topics: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal, Murine-Derived; Antineoplastic Combined Chemotherapy Protocols; Boronic Acids; Bortezomib; Cyclophosphamide; Disease-Free Survival; Doxorubicin; Female; Follow-Up Studies; Hematologic Diseases; Humans; Infusions, Intravenous; Kaplan-Meier Estimate; Lymphoma, Mantle-Cell; Male; Middle Aged; Prednisone; Pyrazines; Rituximab; Vincristine
PubMed: 25738670
DOI: 10.1056/NEJMoa1412096 -
Oxidative Medicine and Cellular... 2022Postoperative peritoneal adhesion (PPA) is a major clinical complication after open surgery or laparoscopic procedure. Ligustrazine is the active ingredient extracted...
Postoperative peritoneal adhesion (PPA) is a major clinical complication after open surgery or laparoscopic procedure. Ligustrazine is the active ingredient extracted from the natural herb , which has promising antiadhesion properties. This study is aimed at revealing the underlying mechanisms of ligustrazine in preventing PPA at molecular and cellular levels. Both rat primary peritoneal mesothelial cells (PMCs) and human PMCs were used for analysis in vitro. Several molecular biological techniques were applied to uncover the potential mechanisms of ligustrazine in preventing PPA. And molecular docking and site-directed mutagenesis assay were used to predict the binding sites of ligustrazine with PPAR. The bioinformatics analysis was further applied to identify the key pathway in the pathogenesis of PPA. Besides, PPA rodent models were prepared and developed to evaluate the novel ligustrazine nanoparticles . Ligustrazine could significantly suppress hypoxia-induced PMC functions, such as restricting the production of profibrotic cytokines, inhibiting the expression of migration and adhesion-associated molecules, repressing the expression of cytoskeleton proteins, restricting hypoxia-induced PMCs to obtain myofibroblast-like phenotypes, and reversing ECM remodeling and EMT phenotype transitions by activating PPAR. The antagonist GW9662 of PPAR could restore the inhibitory effects of ligustrazine on hypoxia-induced PMC functions. The inhibitor KC7F2 of HIF-1 could repress hypoxia-induced PMC functions, and ligustrazine could downregulate the expression of HIF-1, which could be reversed by GW9662. And the expression of HIF-1 inhibited by ligustrazine was dramatically reversed after transfection with si-SMRT. The results showed that the benefit of ligustrazine on PMC functions is contributed to the activation of PPAR on the transrepression of HIF-1 in an SMRT-dependent manner. Molecular docking and site-directed mutagenesis tests uncovered that ligustrazine bound directly to PPAR, and Val 339/Ile 341 residue was critical for the binding of PPAR to ligustrazine. Besides, we discovered a novel nanoparticle agent with sustained release behavior, drug delivery efficiency, and good tissue penetration in PPA rodent models. Our study unravels a novel mechanism of ligustrazine in preventing PPA. The findings indicated that ligustrazine is a potential strategy for PPA formation and ligustrazine nanoparticles are promising agents for preclinical application.
Topics: Animals; Ligusticum; Molecular Docking Simulation; Pyrazines; Rats; Tissue Adhesions
PubMed: 35308169
DOI: 10.1155/2022/9226022