Comparative transcriptomic and metabolomics analysis of modified atmosphere responses in Tribolium castaneum (Coleoptera: Tenebrionidae).

Modified atmosphere is effective in controlling Tribolium castaneum Herbst, but it has adaptations. Comprehending the potential mechanism of resistance to T. castaneum in a modified atmosphere will help advance related management methods. This study conducted a comparative transcriptomic and metabolomic analysis to understand the physiological mechanism of T. castaneum in adapting to CO2 stress. Results showed that there were a large number of differentially expressed genes (DEGs) in T. castaneum treated with different concentrations of CO2. Gene ontology (GO) analysis revealed significant enrichment of DEGs mainly in binding, catalytic activity, cell, membrane, membrane part, protein-containing complex, biological regulation, and cellular and metabolic process. Kyoto Encyclopedia of Genes and Genomes analysis showed that different treatments had different effects on the metabolic pathways of T. castaneum. DEGs induced by 25% CO2 were involved in arginine and proline metabolism, and 50% air + 50% CO2 treatment affected most kinds of metabolic pathways, mainly the signal transduction pathway, including PI3K-Akt signaling pathway, AMPK signaling pathway, neurotrophin signaling pathway, insulin signaling pathway, and thyroid hormone signaling. Ribosome and DNA replication were enriched under high CO2 stress (75% and 95%). The metabolomics revealed that different concentrations of CO2 treatments might inhibit the growth of T. castaneum through acidosis, or they may adapt to anoxic conditions through histamine and N-acetylhistamine. Multiple analyses have shown significant changes in histamine and N-acetylhistamine levels, as well as their associated genes, with increasing CO2 concentration. In conclusion, this study comprehensively revealed the molecular mechanism of T. castaneum responding to CO2 stress and provided the basis for an effectively modified atmosphere in the T. castaneum.

Targeting the chemokine receptor CXCR4 with histamine analog to reduce inflammation in juvenile arthritis.

Introduction: Among immune cells, activated monocytes play a detrimental role in chronic and viral-induced inflammatory pathologies, particularly in Juvenile Idiopathic Arthritis (JIA), a childhood rheumatoid arthritis (RA) disease. The uncontrolled activation of monocytes and excessive production of inflammatory factors contribute to the damage of bone-cartilage joints. Despite the moderate beneficial effect of current therapies and clinical trials, there is still a need for alternative strategies targeting monocytes to treat RA. Methods: To explore such an alternative strategy, we investigated the effects of targeting the CXCR4 receptor using the histamine analog clobenpropit (CB). Monocytes were isolated from the blood and synovial fluids of JIA patients to assess CB's impact on their production of key inflammatory cytokines. Additionally, we administered daily intraperitoneal CB treatment to arthritic mice to evaluate its effects on circulating inflammatory cytokine levels, immune cell infiltrates, joints erosion, and bone resorption, as indicators of disease progression. Results: Our findings demonstrated that CXCR4 targeting with CB significantly inhibited the spontaneous and induced-production of key inflammatory cytokines by monocytes isolated from JIA patients. Furthermore, CB treatment in a mouse model of collagen-induce arthritis resulted in a significant decrease in circulating inflammatory cytokine levels, immune cell infiltrates, joints erosion, and bone resorption, leading to a reduction in disease progression. Discussion: In conclusion, targeting CXCR4 with the small amino compound CB shows promise as a therapeutic option for chronic and viral-induced inflammatory diseases, including RA. CB effectively regulated inflammatory cytokine production of monocytes, presenting a potential targeted approach with potential advantages over current therapies. These results warrant further research and clinical trials to explore the full therapeutic potential of targeting CXCR4 with CB-like molecules in the management of various inflammatory diseases.

Intervention for Hepatic and Pulmonary Metastases in Breast Cancer Patients: Prospective, Multi-institutional Registry Study-IMET, Protocol MF 14-02.

BACKGROUND: One fourth of early-stage breast cancer cases become metastatic during the follow-up period. Limited metastasis is a metastatic disease condition in which the number of metastatic sites and the extent of the disease both are limited, and the disease is amenable to metastatic intervention. This prospective study aimed to evaluate intervention for limited metastases in the lung, liver, or both. METHODS: The study enrolled luminal A/B and/or human epidermal growth factor receptor 2 (HER2)-neu+ patients with operable lung and/or liver metastases in the follow-up assessment after completion of primary breast cancer treatment and patients with a diagnosis of metastasis after 2014. Demographic, clinical, tumor-specific, and metastasis detection-free interval (MDFI) data were collected. Bone metastasis in addition to lung and liver metastases also was included in the analysis. The patients were divided into two groups according to the method of treatment for metastases: systemic therapy alone (ST) group or intervention (IT) group. RESULTS: Until June 2020, 200 patients were enrolled in the study. The demographic data were similar between the two groups. The median follow-up time was 77 months (range 55-107 months) in the IT group (n = 119; 59.5%) and 57 months (range 39-84) in the ST-only group (n = 81; 40.5%). The median MDFI was 40 months (range 23-70 months) in the IT group, and 35 months (range 13-61 months) in the ST-only group (p = 0.47). The groups had similar surgeries for the primary tumor and axilla. Most of the patients had liver metastases (49.5%, n = 99), and 42% (n = 84) of the patients had lung metastases. Both lung and liver metastases were found in 8.5% (n = 17) of the patients. The primary tumor was estrogen receptor/progesterone receptor-positive in 75% (n = 150) of the patients, and 32% (n = 64) of the patients had HER2-neu+ tumors. Metastatic-site resection was performed for 32% (n = 64) of the patients, and 27.5% (n = 55) of the patients underwent metastatic ablative interventions. In the Kaplan-Meier survival analysis, the hazard of death (HoD) was 56% lower in the IT group than in the ST-only group (hazard ratio [HR], 0.44; 95% confidence interval [CI] 0.26-0.72; p = 0.001). The HoD was lower in the IT group than in the ST-only group for the patients younger than 55 years (HR, 0.32; 95% CI 0.17-0.62; p = 0.0007). In the multivariable Cox regression model, HoD was significantly lower for the patients who underwent intervention for metastases and had an MDFI longer than 24 months, but their liver metastases doubled the risk of death compared with lung metastases. CONCLUSION: Metastasis-directed interventions have reduced the risk of death for patients with limited lung/liver metastases who are amenable to interventions after completion of primary cancer treatment. For a select group of patients, such as those with luminal A/B or HER2-neu+ breast cancer who are younger than 55 years with limited metastases to the lung and liver or an MDFI longer than 24 months, surgical or ablative therapy for metastases should be considered and discussed on tumor boards.

New Histamine-Related Five-Membered N-Heterocycle Derivatives as Carbonic Anhydrase I Activators.

A series of histamine (HST)-related compounds were synthesized and tested for their activating properties on five physiologically relevant human Carbonic Anhydrase (hCA) isoforms (I, II, Va, VII and XIII). The imidazole ring of HST was replaced with different 5-membered heterocycles and the length of the aliphatic chain was varied. For the most interesting compounds some modifications on the terminal amino group were also performed. The most sensitive isoform to activation was hCA I (KA values in the low micromolar range), but surprisingly none of the new compounds displayed activity on hCA II. Some derivatives (1, 3a and 22) displayed an interesting selectivity for activating hCA I over hCA II, Va, VII and XIII.

Herb pair of Ephedrae Herba-Armeniacae Semen Amarum alleviates airway injury in asthmatic rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Ephedrae Herba (EH, Ephedra sinica Stapf.) and Armeniacae Semen Amarum (ASA, Prunus armeniaca L. var. ansu Maxim.) have been used to treat asthma, cold, fever, and cough in China for thousands of years. AIM OF THE STUDY: In this study, we aimed to investigate the optimal ratio of EH and ASA compatibility (EAC) to reduce airway injury in asthmatic rats and its possible mechanism. METHODS: Rats were sensitized with a mixture of acetylcholine chloride and histamine bisphosphate 1 h before sensitization by intragastric administration of EAC or dexamethasone or saline for 7 days. Subsequently, the ultrastructure of rat airway epithelial tissue changes, apoptosis of the airway epithelial cells, and the expression of mRNA and protein of EGRF and Bcl-2 were detected. RESULTS: Transmission electron microscope: EAC (groups C and E) had the most prominent effect on repairing airway epithelial cells' ultrastructural changes in asthmatic rats. TUNEL: dexamethasone and EAC (groups B、C、E and F) inhibited the apoptosis of airway epithelial cells in asthmatic rats (P < 0.05). In situ hybridization: EAC (group E) inhibited the overexpression of EGFR and Bcl-2 mRNA (P < 0.05).Western Blotting: EAC (groups A、B、C、E and F) inhibited the upregulation of airway epithelial EGFR and Bcl-2 protein expression (P < 0.01). CONCLUSIONS: Our findings indicate that EAC can inhibit abnormal changes in airway epithelial structure and apoptosis of airway epithelial cells, thereby alleviating airway injury. In this study, the best combination of EH and ASA to alleviate airway epithelial injury in asthmatic rats was group E (EH: ASA = 8: 4.5).

Safety, pharmacokinetics and pharmacodynamics of a novel anti-asthmatic drug, XC8, in healthy probands.

INTRODUCTION: XC8 (histamine glutarimide) is a novel agent which targets eosinophilic migration and mast cell degranulation and has shown anti-asthmatic effects in animal studies. OBJECTIVE: The objective of this placebo-controlled phase 1 study was to assess the safety of oral XC8 and to evaluate its pharmacokinetic and pharmacodynamic properties. METHODS: 32 healthy volunteers in three dose-escalation treatment groups (10 mg [n = 8], 50 mg [n = 8] and 200 mg [n = 16]) were randomized in a 3:1 ratio to XC8 or placebo respectively. The subjects received a single dose of the drug at Day 1 and then once-daily for 14 days (Days 8-21). RESULTS: No severe adverse events occurred. The number of adverse events was similar in the treatment arms compared to placebo and all subjects completed the study as planned. No clinically significant changes occurred in hematologic and biochemical blood tests in subjects receiving XC8. The pharmacokinetic data showed similar dose and time dependent mean plasma XC8 concentrations after single (Day 1) and multiple (Day 21) dosing. The mean maximum concentrations were 114-1993 ng/mL after single and 115-2089 ng/mL after multiple dosing. The mean times to maximum concentration were 0.68-1.01 and 0.67-0.98 h, respectively. There was no evidence for accumulation of XC8 after multiple dosing. CONCLUSION: XC8 was safe and well tolerated. A phase 2 study is being performed to further evaluate the potential role of XC8 in asthma treatment. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02882217.

Identification and biosynthesis of 2-(1H-imidazol-5-yl) ethan-1-ol (histaminol) in methanogenic archaea.

Histaminol is a relatively rare metabolite most commonly resulting from histidine metabolism. Here we describe histaminol production and secretion into the culture broth by the methanogen Methanococcus maripaludis S2 as well as a number of other methanogens. This work is the first identification of this compound as a natural product in methanogens. Its biosynthesis from histidine was confirmed by the incorporation of 2H3-histidine into histaminol by growing cells of M. maripaludis S2. Possible functions of this molecule could be cell signaling as observed with histamine in eukaryotes or uptake of metal ions.

The efficacy and safety of mivacurium in pediatric patients.

BACKGROUND: Mivacurium is the shortest acting nondepolarizing muscle relaxant currently available; however, the effect of different dosages and injection times of intravenous mivacurium administration in children of different ages has rarely been reported. This study was aimed to evaluate the muscle relaxant effects and safety of different mivacurium dosages administered over different injection times in pediatric patients. METHODS: Six hundred forty cases of pediatric patients, aged 2 m-14 years, ASA I or II, were divided into four groups (Groups A, B, C, D) according to the age class (2-12 m, 13-35 m, 3-6 years and 7-14 years) respectively, also each group were divided into four subgroups by induction dose (0.15, 0.2 mg/kg in 2-12 m age class; 0.2, 0.25 mg/kg in other three age classes), and mivacurium injection time (20 s, 40 s), totally 16 subgroups. Neuromuscular transmission was monitored with supramaximal train-of-four stimulation of the ulnar nerve. Radial artery blood (1 ml) was sampled to quantify plasma histamine concentrations before and 1, 4, and 7 min after mivacurium injection (P0, P1, P2 and P3). RESULTS: Five hundred sixty-two cases completed the study. There were no demographic differences within the four groups. The onset time of 0.2 mg/kg groups in 2-12 m aged patients were shorter than those of 0.15 mg/kg groups (189 ± 64 s vs. 220 ± 73 s, 181 ± 60 s vs. 213 ± 71 s, P <0.05), and the recovery times were no statistical differences. The T1 25% recovery time of 0.2 mg/kg in 3-6 years aged patients was shorter than that of 0.25 mg/kg group (693 ± 188 s vs. 800 ± 206 s, P <0.05). The onset and recovery times of mivacurium were not different in 13-35 m and 7-14 years aged patients. The plasma concentrations of histamine at P0, P1, P2 and P3 were not different within four groups. CONCLUSIONS: The induction dose and injection time of mivacurium had mostly insignificant effects on onset and recovery times. The main exception to this was that in 2-12 m aged patients, increasing the dose of mivacurium from 0.15 to 0.2 mg/kg accelerated the onset time by about 30 s. Mivacurium produced no significant release of histamine in any age group at the doses studied. TRIAL REGISTRATION: ClinicalTrials.gov Identifier- NCT02117401 , July 14, 2014. (Retrospectively registered).

Metabolomics analysis of anaphylactoid reaction reveals its mechanism in a rat model.

BACKGROUND: Anaphylactoid reactions, accounting for more than 77% of all immune-mediated immediate hypersensitivity reactions, have become a serious threat to public health, but their effect mechanism is not clear and diagnostic tests are limited. Comprehensive metabolite analysis may reveal the anaphylactoid effect mechanism systematically and provide reference for future diagnostic purposes. METHODS: Plasma from Brown Norway rats given intravenous injection of saline, compound 48/80 (2.5 mL/kg) or ovalbumin (20 mL/kg) in 20 s for the first time was used to study the effect mechanism of anaphylactoid reactions through metabolomics (UPLC-qTOF-MS/MS). Metabolomics integrated with proteomics data were used to analyze the anaphylactoid pathways by MetaboAnalyst followed by integrated pathway analysis. RESULTS: Thirty metabolites were identified through the METLIN database by MS/MS and 18 of them were confirmed by authentic standards. The results showed that adenosine, histamine, N-acetylhistamine, N(α)-γ-glutamylhistamine, malate and xanthine are important indices for anaphylactoid reactions. It could be concluded that the effect mechanism is mainly composed of histidine metabolism, arachidonic acid metabolism, energy metabolism, purine metabolism and other small molecules through 30 metabolites. Multiple linear regression analysis indicated that not only histamine but also N(α)-γ-glutamylhistamine and arachidonic acid could be used to evaluate anaphylactoid symptoms of animals. Furthermore, the citrate cycle, histidine metabolism and arachidonic acid metabolism could be the main pathways of anaphylactoid reactions as determined by MetaboAnalyst. CONCLUSION: The results may provide a reference to improve diagnostic accuracy and predict and monitor treatment efficacy in anaphylactoid reactions in the clinical setting.

Transferrin-inspired vehicles based on pH-responsive coordination bond to combat multidrug-resistant breast cancer.

A novel biomimetic drug delivery system (BDDS) inspired by the pH-dependent ferric ion-transport and release manner of transferrin (Tf) was developed for combating multidrug-resistant breast cancer. Tf-inspired carrier was synthesized by modifying bovine serum albumin (BSA) with histamine (HA) through amide reaction to provide superior specific coordination sites for ferric ion-drug complexes, and self-assembled into nanoparticles (NPs) induced by coordination bond. Tf-inspired NPs were prepared via environment-friendly method, and well redispersed in saline after lyophilization. When internalized into tumor cells by SPARC (secreted protein acidic and rich in cysteine) mediated endocytosis, Tf-inspired NPs bypassed and decreased the P-glycoprotein-mediated drug efflux and led to more effective treatment of multidrug-resistant breast cancer compared with free drugs both in vitro and in vivo due to the enhanced cellular uptake and rapid pH-responsive drug release. Moreover, Tf-inspired NPs exhibited good biocompatibility and low systemic toxicity. Thus, our results demonstrate that Tf-inspired NPs based on coordination bond represent as a smart drug delivery strategy to combat multidrug-resistant cancer and have great potential for clinical applications in cancer therapy.

Comparison of different local and imported histamine concentrations used as a skin prick test positive control.

BACKGROUND: The skin prick test (SPT) is a valid and approved tool that is used to diagnose atopic diseases. The SPT is accurate, safe, simple and inexpensive. However, the histamine concentration used as a positive control in the SPT varies among centers. OBJECTIVE: To compare SPT results using different concentrations of locally-prepared and imported histamine solutions. METHOD: This prospective, randomized, double-blind, self-controlled study was performed in healthy adult volunteers. The SPT was performed using 4 concentrations of histamine solutions (imported, 1 mg/mL; locally-prepared, 1, 5 and 10 mg/mL). Locally-prepared histamine positive controls were prepared from histamine biphosphate monohydrate using sterile technique. RESULTS: Seventy-five adult volunteers (mean age, 36 years) were included in the study. Eight volunteers were male and 9 had a history of atopy. Mean wheal diameter (MWD) for imported histamine was 3.49 mm for a concentration of 1 mg/mL, and that of locally-prepared histamine was 2.94 mm, 5.05 mm and 5.52 mm for concentrations of 1, 5 and 10 mg/mL histamine, respectively. Negative SPT results (MWD <3 mm) were found in 11 subjects (14.7%) who received imported histamine and 26 subjects (34.7%) who received the locally-prepared histamine at concentration of 1 mg/mL. All subjects tested with locally-prepared histamine at concentrations of 5 and 10 mg/mL had a MWD > 3 mm. CONCLUSIONS: Locally-prepared histamine base at concentrations of 5 and 10 mg/mL yielded better positive results than both imported and locally-prepared histamine at a concentration of 1 mg/mL.

[Active sites of N-acetylhexosamine 1-kinase from Bifidobacterium longum].

OBJECTIVE: To study the active sites of N-acetylhexosamine 1-kinase (NahK) from Bifidobacterium longum JCM12 17. METHODS: We obtained expression strains of 10 single-mutants at 4 sites of NahK by site-directed mutagenesis, and expressed and purified both wild-type (WT) and mutant enzymes. Then, their optimum pH and optimum concentration of Mg²âº were determined by DNS assay and NADH-coupled microplate photometric assay, and their kinetic parameters were measured. RESULTS: Four mutants (D208A, D208N, D208E and I24A) lost most part of the catalytic activity. The optimum pH of mutants H31A, H31V, F247A and I24V switched from pH 7.5 (for WT) to pH 7.0, and the optimum concentration of Mg²âº of mutants H31A and F247A increased to 10 mmol/L from 5 mmol/L (for WT). The kinetic parameters of WT and mutants indicate that mutant F247Y had higher enzymatic activity toward GlcNAc, GalNAc and ATP than WT. CONCLUSION: The key amino acids that affect the catalytic activity of NahK were determined by site-directed mutagenesis, and together with the mutant that has higher catalytic efficiency, this has laid a foundation for further modification and evolution of NahK.

Factors influencing the formation of histaminol, hydroxytyrosol, tyrosol, and tryptophol in wine: Temperature, alcoholic degree, and amino acids concentration.

The validation of a HPLC-PDA-MS/MS chromatographic method for the quali/quantitative characterization of histaminol, hydroxytyrosol, tyrosol, and tryptophol in wine has been described and discussed. Four standards showed a good linearity with high correlation coefficient values (over 0.9989) and LOD and LOQ were 0.001-0.015 mg/L and 0.004-0.045 mg/L, respectively. Furthermore, this study reported how factors such as temperature, alcoholic degree, and amino acids concentration are able to influence the formation of these four alcohols in Monastrell wines. The quantification values of these alcohols has been detected both at the half and end of alcoholic fermentation, and at the end of malolactic fermentation. In relation to interactions between factors, several significant variations emerged (p ⩽ 0.001). The impact of amino acids supplementation in Monastrell must it has been demonstrated, mainly in regards to histaminol and tryptophol.

Mechanistic and Structural Analysis of a Drosophila melanogaster Enzyme, Arylalkylamine N-Acetyltransferase Like 7, an Enzyme That Catalyzes the Formation of N-Acetylarylalkylamides and N-Acetylhistamine.

Arylalkylamine N-acetyltransferase like 7 (AANATL7) catalyzes the formation of N-acetylarylalkylamides and N-acetylhistamine from acetyl-CoA and the corresponding amine substrate. AANATL7 is a member of the GNAT superfamily of >10000 GCN5-related N-acetyltransferases, many members being linked to important roles in both human metabolism and disease. Drosophila melanogaster utilizes the N-acetylation of biogenic amines for the inactivation of neurotransmitters, the biosynthesis of melatonin, and the sclerotization of the cuticle. We have expressed and purified D. melanogaster AANATL7 in Escherichia coli and used the purified enzyme to define the substrate specificity for acyl-CoA and amine substrates. Information about the substrate specificity provides insight into the potential contribution made by AANATL7 to fatty acid amide biosynthesis because D. melanogaster has emerged as an important model system contributing to our understanding of fatty acid amide metabolism. Characterization of the kinetic mechanism of AANATL7 identified an ordered sequential mechanism, with acetyl-CoA binding first followed by histamine to generate an AANATL7·acetyl-CoA·histamine ternary complex prior to catalysis. Successive pH-activity profiling and site-directed mutagenesis experiments identified two ionizable groups: one with a pKa of 7.1 that is assigned to Glu-26 as a general base and a second pKa of 9.5 that is assigned to the protonation of the thiolate of the coenzyme A product. Using the data generated herein, we propose a chemical mechanism for AANATL7 and define functions for other important amino acid residues involved in substrate binding and regulation of catalysis.

Poly(amido amine)-based multilayered thin films on 2D and 3D supports for surface-mediated cell transfection.

Two linear poly(amido amine)s, pCABOL and pCHIS, prepared by polyaddition of cystamine bisacrylamide (C) with 4-aminobutanol (ABOL) or histamine (HIS), were explored to form alternating multilayer thin films with DNA to obtain functionalized materials with transfection capacity in 2D and 3D. Therefore, COS-7 cells were cultured on top of multilayer films formed by layer-by-layer dipcoating of these polymers with GFP-encoded pDNA, and the effect of the number of layers and cell seeding density on the transfection efficiency was evaluated. Multilayer films with pCABOL were found to be superior to pCHIS in facilitating transfection, which was attributed to higher incorporation of pDNA and release of the transfection agent. High amounts of transfected cells were obtained on pCABOL films, correlating proportionally over a wide range with seeding density. Optimal transfection efficiency was obtained with pCABOL films composed of 10 bilayers. Further increase in the number of bilayers only marginally increased transfection efficiency. Using the optimal multilayer and cell seeding conditions, pCABOL multilayers were fabricated on poly(ε-caprolactone) (PCL), heparinized PCL (PCL-HEP), and poly(lactic acid) (PLA) disks as examples of common biomedical supports. The multilayers were found to completely mask the properties of the original substrates, with significant improvement in cell adhesion, which is especially pronounced for PCL and PLA disks. With all these substrates, transfection efficiency was found to be in the range of 25-50% transfected cells. The pCABOL/pDNA multilayer films can also conveniently add transfection capability to 3D scaffolds. Significant improvement in cell adhesion was observed after multilayer coating of 3D-plotted fibers of PCL (with and without an additional covalent heparin layer), especially for the PCL scaffold without heparin layer and transfection was observed on both 3D PCL and PCL-HEP scaffolds. These results show that layer-by-layer dip-coating of pCABOL with functional DNA is an easy and inexpensive method to introduce transfection capability to biomaterials of any nature and shape, which can be beneficially used in various biomedical and tissue engineering applications.

Effect of defatting on quality of meat and bone meal.

Meat and bone meal (MBM), a type of protein feed source, with high nutritional value, has been widely used as feed in China. In order to study the effect of defatting on the quality of MBM, MBM were defatted by hexane, and their basic nutritional components, color, flavor, protein characteristics, freshness indexes before and after defatting, were investigated. The crude protein content of the defatted MBM was increased from 54.5% to 61.2%, lysine content increased from 1.83 to 1.96%, pure protein content and in vitro digestibility of MBM were increased to 50.7% and 90.45%, respectively. Acid value decreased from 9.0 to 2.6 mg potassium hydroxide/g, and the color and flavor were also improved after defatting. Furthermore, volatile basic nitrogen content decreased from 60 to 40 mg/100 g and histamine content did not change significantly (decreasing from 20.1 to 19.6 mg/kg). Therefore, defatting treatment was good for the quality improvement of MBM.

Mono- and di-halogenated histamine, histidine and carnosine derivatives are potent carbonic anhydrase I, II, VII, XII and XIV activators.

Mono- and di-halogenated histamines, l-histidine methyl ester derivatives and carnosine derivatives incorporating chlorine, bromine and iodine were prepared and investigated as activators of five carbonic anhydrase (CA, EC 4.2.1.1) isoforms, the cytosolic hCA I, II and VII, and the transmembrane hCA XII and XIV. All of them were activated in a diverse manner by the investigated compounds, with a distinct activation profile.

Simple and sensitive analysis of histamine and tyramine in Japanese soy sauces and their intermediates using the stable isotope dilution HILIC-MS/MS method.

We established a simple, sensitive, and reproducible method to analyze the histamine and tyramine levels in Japanese soy sauce and its mash (called moromi) using hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC-MS/MS). Histamine and tyramine quantification was performed using their stable isotopes for electrospray ionization-tandem mass spectrometry in the selected reaction monitoring mode. The sample pretreatment process was a simple, one-step liquid-liquid extraction. HILIC separation was performed with a gradient elution of aqueous ammonium formate and acetonitrile. Because of validation tests, the linearity, the accuracies, and precisions were sufficient. The limit of detection and the limit of quantification were 0.09 and 0.29 ppm for histamine and 0.13 and 0.42 ppm for tyramine, respectively. We successfully applied this method to histamine and tyramine determination in four kinds of commercial Japanese soy sauces and also in moromi samples during soy sauce production.

Luminescent ruthenium complexes for theranostic applications.

The water-soluble and visible luminescent complexes cis-[Ru(L-L)2(L)2](2+) where L-L = 2,2-bipyridine and 1,10-phenanthroline and L= imidazole, 1-methylimidazole, and histamine have been synthesized and characterized by spectroscopic techniques. Spectroscopic (circular dichroism, saturation transfer difference NMR, and diffusion ordered spectroscopy NMR) and isothermal titration calorimetry studies indicate binding of cis-[Ru(phen)2(ImH)2](2+) and human serum albumin occurs via noncovalent interactions with K(b) = 9.8 × 10(4) mol(-1) L, ΔH = -11.5 ± 0.1 kcal mol(-1), and TΔS = -4.46 ± 0.3 kcal mol(-1). High uptake of the complex into HCT116 cells was detected by luminescent confocal microscopy. Cytotoxicity of cis-[Ru(phen)2(ImH)2](2+) against proliferation of HCT116p53(+/+) and HCT116p53(-/-) shows IC50 values of 0.1 and 0.7 µmol L(-1). Flow cytometry and western blot indicate RuphenImH mediates cell cycle arrest in the G1 phase in both cells and is more prominent in p53(+/+). The complex activates proapoptotic PARP in p53(-/-), but not in p53(+/+). A cytostatic mechanism based on quantification of the number of cells during the time period of incubation is suggested.

Synthesis and functional characterization of imbutamine analogs as histamine H3 and H4 receptor ligands.

Imbutamine (4-(1H-imidazol-4-yl)butanamine) is a potent histamine H3 (H3R) and H4 receptor (H4R) agonist (EC50 values: 3 and 66 nM, respectively). Aiming at improved selectivity for the H4R, the imidazole ring in imbutamine was methyl-substituted or replaced by various differently substituted heterocycles (1,2,3-triazoles, 1,2,4-triazoles, pyridines, pyrimidines) as potential bioisosteres. Investigations in [(35)S]GTPγS binding assays using membranes of Sf9 insect cells expressing the respective human histamine receptor subtype revealed only very weak activity of most of the synthesized hetarylalkylamines at both receptors. By contrast, the introduction of substituents at the 4-imidazolyl ring was most effective regarding H4R selectivity. This holds for methyl substitution in position 2 and, especially, in position 5. 5-Methylimbutamine (H4R: EC50 = 59 nM, α = 0.8) was equipotent with imbutamine at the hH4R, but revealed about 16-fold selectivity for the hH4R compared to the hH3R (EC50 980 nM, α = 0.36), whereas imbutamine preferred the hH3R. The functional activities were in agreement with radioligand binding data. The results support the hypothesis that, by analogy with histamine, methyl substitution in histamine homologs offers a way to shift the selectivity in favor of the H4R.