Inhibitory Activity Against Rhizoctonia Solani and Chemical Composition of Extract from Moutan Cortex

Rice sheath blight (RSB), caused by Rhizoctonia solani, is a significant disease of rice. The negative effects of chemical fungicides have created an urgent need for low-toxicity botanical fungicides. Our previous research revealed that the ethanol crude extract of Moutan Cortex (MC) exhibited superior antifungal activity against R. solani at 1000 μg/mL, resulting in a 100 % inhibition rate. The antifungal properties were mainly found in the petroleum ether extract. However, the active ingredients of the extract are still unclear. In this study, gas chromatography-mass spectrometry (GC-MS) was utilised for the analysis of its chemical components. The mycelium growth rate method was utilized to detect the antifungal activity. The findings indicated that paeonol constituted the primary active component, with a content of more than 96 %. Meanwhile, paeonol was the most significant antifungal active ingredient, the antifungal activity of paeonol (EC50=44.83 μg/mL) was much higher than that of β-sitosterol and ethyl propionate against R. solani. Observation under an optical microscope revealed that paeonol resulted in abnormal mycelial morphology. This study provided theoretical support for identifying monomer antifungal compounds and developing biological fungicides for R. solani.

Investigation on the inhibition mechanism and binding behavior of paeonol to tyrosinase and its anti-browning property by multi-spectroscopic and molecular docking methods

Paeonol, as one effective tyrosinase inhibitor, had been used as food preservative and clinical medication for skin disorders. In this study, the inhibition mechanism and binding behavior of paeonol to tyrosinase and its anti-browning property were investigated using multi-spectroscopic and molecular docking methods. Activity assay and kinetic results confirmed paeonol as a reversible mixed-type tyrosinase inhibitor. Results of the mechanistic studies were clarified using fluorescence quenching, synchronous fluorescence, CD spectra and 3D fluorescence, and showed that the binding of paeonol to tyrosinase might change the chromophore microenvironment and conformation of tyrosinase to inhibit enzyme catalytic activity. Molecular docking results revealed the detailed binding between paeonol and tyrosinase. Moreover, paeonol could prevent the browning of fresh-cut apples, as well as inhibiting PPO and POD activities and increasing APX activity. All above findings established a reliable basis for the inhibitory mechanism of paeonol against tyrosinase and therefore contributed to its application in anti-browning.

In vitro-in vivo assessments of apocynin-hybrid nanoparticle-based gel as an effective nanophytomedicine for treatment of rheumatoid arthritis

Apocynin (APO), a well-known bioactive plant-based phenolic phytochemical with renowned anti-inflammatory and antioxidant pharmacological activities, has recently emerged as a specific nicotinamide adenine dinucleotide phosphate-oxidase (NADPH) oxidase inhibitor. As far as we know, no information has been issued yet regarding its topical application as a nanostructured-based delivery system. Herein, APO-loaded Compritol® 888 ATO (lipid)/chitosan (polymer) hybrid nanoparticles (APO-loaded CPT/CS hybrid NPs) were successfully developed, characterized, and optimized, adopting a fully randomized design (32) with two independent active parameters (IAPs), namely, CPT amount (XA) and Pluronic® F-68 (PF-68) concentration (XB), at three levels. Further in vitro-ex vivo investigation of the optimized formulation was performed before its incorporation into a gel base matrix to prolong its residence time with consequent therapeutic efficacy enhancement. Subsequently, scrupulous ex vivo-in vivo evaluations of APO-hybrid NPs-based gel (containing the optimized formulation) to scout out its momentous activity as a topical nanostructured system for beneficial remedy of rheumatoid arthritis (RA) were performed. Imperatively, the results support an anticipated effectual therapeutic activity of the APO-hybrid NPs-based gel formulation against Complete Freund's Adjuvant-induced rheumatoid arthritis (CFA-induced RA) in rats. In conclusion, APO-hybrid NPs-based gel could be considered a promising topical nanostructured system to break new ground for phytopharmaceutical medical involvement in inflammatory-dependent ailments.

Traveling across Life Sciences with Acetophenone-A Simple Ketone That Has Special Multipurpose Missions

Each metabolite, regardless of its molecular simplicity or complexity, has a mission or function in the organism biosynthesizing it. In this review, the biological, allelochemical, and chemical properties of acetophenone, as a metabolite involved in multiple interactions with various (mi-cro)organisms, are discussed. Further, the details of its biogenesis and chemical synthesis are provided, and the possibility of its application in different areas of life sciences, i.e., the status quo of acetophenone and its simple substituted analogs, is examined. In particular, natural and synthetic simple acetophenone derivatives are analyzed as promising agrochemicals and useful scaffolds for drug research and development.

Investigation on the antitumor effects of paeonol against renal cell carcinoma based on network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Renal cell carcinoma (RCC) is the most common cancer of the urinary system, the current treatments for RCC are unsatisfactory. Paeonol is the main pharmacologically active ingredient of the traditional Chinese medicine (TCM) moutan cortex (Paeonia suffruticosa Andrews) and Paeonia albiflora Pall, and has been used in TCM to treat various diseases including cancer. However, the underlying therapeutic mechanisms of paeonol in RCC have not been investigated yet.

AIM OF THE STUDY

This study aimed to explore the potential antitumor effects and mechanisms of paeonol on RCC based on network pharmacology and experimental validation.

MATERIALS AND METHODS

Network pharmacological analysis was performed to predict the potential targets and mechanism of paeonol against RCC. The antitumor effects and the priority targets of paeonol against RCC were further assessed by in vitro experiments.

RESULTS

104 intersection targets shared by paeonol and RCC were collected, 15 hub genes were obtained, among these genes, VEGFA expression was higher in RCC, and the higher expression of IL-6 or lower expression of AKT1, JUN, MAPK1, and MAPK8 were correlated to the shorter overall survival (OS) in RCC patients. GO and KEGG analyses suggested that the genes were mainly enriched in the positive regulation of cell death and apoptosis pathway. In vitro experiments showed that paeonol inhibited 786-O cell proliferation, migration, invasion, and promoted apoptosis. When 786-O cells were treated with paeonol, the expression of Bax increased while Bcl-2 and VEGFA decreased.

CONCLUSION

The present study demonstrated that paeonol might play an essential role in RCC by regulating cell proliferation, apoptosis, metastasis, and invasion through the Bcl-2/Bax signaling pathway and VEGFA, providing a theoretical and experimental scientific basis for future investigations of the antitumor effects of paeonol against RCC.

Lignin-Derived Syringol and Acetosyringone from Palm Bunch Using Heterogeneous Oxidative Depolymerization over Mixed Metal Oxide Catalysts under Microwave Heating

Biomass valorization to building block chemicals in food and pharmaceutical industries has tremendously gained attention. To produce monophenolic compounds from palm empty fruit bunch (EFB), EFB was subjected to alkaline hydrothermal extraction using NaOH or K2CO3 as a promotor. Subsequently, EFB-derived lignin was subjected to an oxidative depolymerization using Cu(II) and Fe(III) mixed metal oxides catalyst supported on γ-Al2O3 or SiO2 as the catalyst in the presence of hydrogen peroxide. The highest percentage of total phenolic compounds of 63.87 wt% was obtained from microwave-induced oxidative degradation of K2CO3 extracted lignin catalyzed by Cu-Fe/SiO2 catalyst. Main products from the aforementioned condition included 27.29 wt% of 2,4-di-tert-butylphenol, 19.21 wt% of syringol, 9.36 wt% of acetosyringone, 3.69 wt% of acetovanillone, 2.16 wt% of syringaldehyde, and 2.16 wt% of vanillin. Although the total phenolic compound from Cu-Fe/Al2O3 catalyst was lower (49.52 wt%) compared with that from Cu-Fe/SiO2 catalyst (63.87 wt%), Cu-Fe/Al2O3 catalyst provided the greater selectivity of main two value-added products, syringol and acetosyrigone, at 54.64% and 23.65%, respectively (78.29% total selectivity of two products) from the NaOH extracted lignin. The findings suggested a promising method for syringol and acetosyringone production from the oxidative heterogeneous lignin depolymerization under low power intensity microwave heating within a short reaction time of 30 min.

Semiochemical signatures associated with differential attraction of Anopheles gambiae to human feet

BACKGROUND

Several human-produced volatiles have been reported to mediate the host-seeking process under laboratory conditions, yet no effective lure or repellent has been developed for field application. Previously, we found a gradation of the attractiveness of foot odors of different malaria free individuals to Anopheles gambiae sensu stricto Giles. In this study, foot odor of the individual with the most attractive 'smelly' feet to the An. gambiae was collected, analyzed and attractive blend components identified.

METHODS

The foot odor of the individual with the most attractive 'smelly' feet to the An. gambiae was trapped on Porapak Q and analyzed by gas chromatography-linked mass spectrometry (GC-MS). Specific constituents perceived by the insect olfactory system were then identified by GC-linked to electro-antennography detector (GC-EAD) and characterized by GC-MS. The contribution of each constituent to the behavioral response of An. gambiae was assessed through subtractive assays under semi-field conditions in a screen-house using Counter Flow Geometry (CFG traps) baited with (i) the blend of all the EAD-active and (ii) other blends containing all components with exclusion of one component at a time. The number of mosquitoes trapped in the baited CFG traps were compared with those in the control traps.

RESULTS

Eleven major and minor constituents: 2 carboxylic acids, six aldehydes, two ketones and one phenolic compound, were confirmed to be EAD-active. The contribution of each constituent to the behavioral response of An. gambiae was assessed through subtractive assays under semi- field conditions. Exclusion/ subtraction of one of the following compounds: i-butyric acid, i-valeric acid, n-octanal, n-nonanal, n-decanal, n-dodecanal, undecanal or n-tridecanal, from each blend led to reduction in the attractiveness of all the resulting blends, suggesting that all of them are critical/important for the attractiveness of the foot odor to An. gambiae mosquitoes. However, exclusion/subtraction of 4-ethoxyacetophenone, 4-ethylacetophenone and/or 2-methylphenol, led to significant enhancements in the attractiveness of the resulting blends, suggesting that each of these compounds had repellent effect on An. gambiae ss. Undecanal exhibited kairomonal activity at low natural concentrations under semi-field conditions but repellent activity at high unnatural conditions in the laboratory. Furthermore, the comparison of the mean mosquito catches in traps baited with the nine-component blend without 4-ethoxyacetophenone, 4-ethylacetophenone and the complete foot odor collection revealed that the former is significantly more attractive and confirmed the repellent effect of the two carbonyl compounds at low natural concentration levels.

CONCLUSION

These results suggest that differential attractiveness of An. gambiae to human feet is due to qualitative and/or qualitative differences in the chemical compositions of the foot odors from individual human beings and relative proportions of the two chemical signatures (attractants versus repellents) as observed from the ratios of the bioactive components in the foot odors of the most attractive and least attractive individuals. Chemical signature means the ensemble of the compounds released by the organism in a specific physiological state. The chemical signature is emitter-dependent, but does not depend on receiver response. Thus, there is only one chemical signature for one individual or species that may eventually include inactive, attractive and repellent components for another organism. The nine-component attractive blend has a potential as an effective field bait for trapping of malaria vectors in human dwellings.

Regulation of Keap-1/Nrf2/AKT and iNOS/NF-κB/TLR4 signals by apocynin abrogated methotrexate-induced testicular toxicity: Mechanistic insights and computational pharmacological analysis

AIM

Male reproductive toxicity is becoming of growing significance due to clinical chemotherapy usage. Methotrexate (MTX) is an anti-folate used on a large scale for different tumors and autoimmune conditions. Despite its wide clinical use, MTX is associated with severe testicular intoxication. The exact underlying mechanism is unclear.

METHODS

Our study was conducted to explore the pathogenesis mechanism of MTX-induced testicular damage and the potential testicular protective effects of apocynin (APO) on testicular injury induced by single i.p. MTX (20 mg/kg). APO was administered orally (100 mg/kg) for ten days.

RESULTS

As compared to rats given MTX alone, co-administration of MTX with APO demonstrated multiple beneficial effects evidenced by a marked increase in testosterone, FSH, and LH and significantly restored testes histopathological alterations. Mechanistically, APO restored antioxidant status through up-regulation of Nrf2, cytoglobin, PPAR-γ, SIRT1, AKT, and p-AKT, while effectively lowering Keap-1. Moreover, APO significantly attenuated inflammation by down-regulating NF-κB-p65, iNOS, and TLR4 expressions confirmed by in-silico evidence. Additionally, network pharmacology analysis, a bioinformatics approach, was used to decipher various cellular processes' molecular mechanisms.

SIGNIFICANCE

The current investigation proves the beneficial effects of APO in MTX-associated testicular damage through activation of cytoglobin, Keap-1/Nrf2/AKT, PPAR-γ, SIRT1, and suppressing of TLR4/NF-κB-p65 signal. Our data collectively encourage extending the investigation to the clinical setting to explore APO effects in MTX-treated patients.

Neuroprotective Ability of Apocynin Loaded Nanoparticles (APO-NPs) as NADPH Oxidase (NOX)-Mediated ROS Modulator for Hydrogen Peroxide-Induced Oxidative Neuronal Injuries

Apocynin (APO) is a known multi-enzymatic complexed compound, employed as a viable NADPH oxidase (NOX) inhibitor, extensively used in both traditional and modern-day therapeutic strategies to combat neuronal disorders. However, its therapeutic efficacy is limited by lower solubility and lesser bioavailability; thus, a suitable nanocarrier system to overcome such limitations is needed. The present study is designed to fabricate APO-loaded polymeric nanoparticles (APO-NPs) to enhance its therapeutic efficacy and sustainability in the biological system. The optimized APO NPs in the study exhibited 103.6 ± 6.8 nm and -13.7 ± 0.43 mV of particle size and zeta potential, respectively, along with further confirmation by TEM. In addition, the antioxidant (AO) abilities quantified by DPPH and nitric oxide scavenging assays exhibited comparatively higher AO potential of APO-NPs than APO alone. An in-vitro release profile displayed a linear diffusion pattern of zero order kinetics for APO from the NPs, followed by its cytotoxicity evaluation on the PC12 cell line, which revealed minimal toxicity with higher cell viability, even after treatment with a stress inducer (H2O2). The stability of APO-NPs after six months showed minimal AO decline in comparison to APO only, indicating that the designed nano-formulation enhanced therapeutic efficacy for modulating NOX-mediated ROS generation.

Computational Structural Revision of a 4-Hydroxy-3-(1'-angeloyloxy-2',3'-epoxy-3'-methyl)butylacetophenone Compound from Ageratina grandifolia

The structure of the reported compound 4-hydroxy-3-((S)-1'-angeloyloxy-(R)-2',3'-epoxy-3'-methyl)butylacetophenone (1), isolated from Ageratina grandifolia, has been revised through the use of DFT computational predictions. Re-examination of the reported experimental and DFT computed chemical shifts has led to the proposal of a chromane skeleton rather than the original epoxide derivative. Empirical predictions of the ¹³C and ¹H NMR shifts showed a much better fit for the chromane structure than for the epoxide. The relative configuration of the molecule was established using CASE-3D methodology on the basis of new DFT chemical shielding and J-coupling predictions, allowing the proposal of a new rel-2,2-dimethyl-3R-hydroxy-4S-(1-angeloyloxy)chromane structure (2) for the isolated compound. However, DFT prediction of the optical rotation for the CASE-3D selected configuration/conformations did not provide a conclusive answer for the absolute configuration.

Synthesis and Antinociceptive Effect of Some Thiazole-Piperazine Derivatives: Involvement of Opioidergic System in the Activity

In this study, we aimed to design and synthesize novel molecules carrying both the thiazole and piperazine rings in their structures and to investigate their antinociceptive activity. Targeted compounds were obtained by reacting thiosemicarbazide derivative and appropriate 2-bromoacetophenone in ethanol. The structures of the obtained compounds were determined using data from various spectroscopic methods (IR, ¹H-NMR, ¹³C-NMR, and LCMSMS). Experimental data from in vivo tests showed that test compounds 3a–3c, 3f, and 3g (50 mg/kg) significantly prolonged reaction times of animals in tail-clip and hot-plate tests compared to the controls, indicating that these compounds possess centrally mediated antinociceptive activities. Furthermore, these compounds reduced the number of writhing behaviors in the acetic acid-induced writhing tests, showing that the compounds also possess peripheral antinociceptive activity. In the mechanistic studies, naloxone pre-treatments abolished the antinociceptive activities of compounds 3a–3c, 3f, and 3g, indicating that opioidergic mechanisms were involved in their antinociceptive effects. Molecular docking studies demonstrating significant interactions between the active compounds and µ- and δ-opioid receptor proteins supported the pharmacological findings. This study is the first showing that molecules designed to bear thiazole and piperazine moieties together on their structure exert centrally and peripherally mediated antinociceptive effects by activating the opioid system.

Chromoselective Photocatalysis Enables Stereocomplementary Biocatalytic Pathways*

Controlling the selectivity of a chemical reaction with external stimuli is common in thermal processes, but rare in visible-light photocatalysis. Here we show that the redox potential of a carbon nitride photocatalyst (CN-OA-m) can be tuned by changing the irradiation wavelength to generate electron holes with different oxidation potentials. This tuning was the key to realizing photo-chemo-enzymatic cascades that give either the (S)- or the (R)-enantiomer of phenylethanol. In combination with an unspecific peroxygenase from Agrocybe aegerita, green light irradiation of CN-OA-m led to the enantioselective hydroxylation of ethylbenzene to (R)-1-phenylethanol (99 % ee). In contrast, blue light irradiation triggered the photocatalytic oxidation of ethylbenzene to acetophenone, which in turn was enantioselectively reduced with an alcohol dehydrogenase from Rhodococcus ruber to form (S)-1-phenylethanol (93 % ee).

New Acetophenones and Chromenes from the Leaves of Melicope barbigera A. Gray

The dichloromethane extract from leaves of Melicope barbigera (Rutaceae), endemic to the Hawaiian island of Kaua'i, yielded four new and three previously known acetophenones and 2H-chromenes, all found for the first time in M. barbigera. The structures of the new compounds obtained from the dichloromethane extract after purification by chromatographic methods were unambiguously elucidated by spectroscopic analyses including 1D/2D NMR spectroscopy and HRESIMS. The absolute configuration was determined by modified Mosher's method. Compounds 2, 4 and the mixture of 6 and 7 exhibited moderate cytotoxic activities against the human ovarian cancer cell line A2780 with IC₅₀ values of 30.0 and 75.7 µM for 2 and 4, respectively, in a nuclear shrinkage cytotoxicity assay.

Lithium Hydroxide Hydrolysis Combined with MALDI TOF Mass Spectrometry for Rapid Sphingolipid Detection

Sphingolipids have diverse structural and bioactive functions that play important roles in many key biological processes. Factors such as low relative abundance, varied structures, and a dynamic concentration range provide a difficult analytical challenge for sphingolipid detection. To further improve mass-spectrometry-based sphingolipid analysis, lithium adduct consolidation was implemented to decrease spectral complexity and combine signal intensities, leading to increased specificity and sensitivity. We report the use of lithium hydroxide as a base in a routine hydrolysis procedure in order to effectively remove common ionization suppressants (such as glycolipids and glycerophospholipids) and introduce a source of lithium into the sample. In conjunction, an optimized MALDI matrix system, featuring 2',4',6'-trihydroxyacetophenone (THAP) is used to facilitate lithium adduct consolidation during the MALDI process. The result is a robust and high-throughput sphingolipid detection scheme, particularly of low-abundance ceramides. Application of our developed workflow includes the detection of differentially expressed liver sphingolipid profiles from a high-fat-induced obesity mouse model. We also demonstrate the method's effectiveness in detecting various sphingolipids in brain and plasma matrices. These results were corroborated with data from UHPLC HR MS/MS and MALDI FT-ICR, verifying the efficacy of the method application. Overall, we demonstrate a high-throughput workflow for sphingolipid analysis in various biological matrices by the use of MALDI TOF and lithium adduct consolidation.

Non-invasive intranasal administration route directly to the brain using dendrimer nanoplatforms: An opportunity to develop new CNS drugs

There are several routes of administration to the brain, including intraparenchymal, intraventricular, and subarachnoid injections. The blood-brain barrier (BBB) impedes the permeation and access of most drugs to the central nervous system (CNS), and consequently, many neurological diseases remain undertreated. For past decades, to circumvent this effect, several nanocarriers have been developed to deliver drugs to the brain. Importantly, intranasal (IN) administration can allow direct delivery of drugs into the brain through the anatomical connection between the nasal cavity and brain without crossing the BBB. In this regard, dendrimers may possess great potential to deliver drugs to the brain by IN administration, bypassing the BBB and reducing systemic exposure and side effects, to treat diseases of the CNS. In this original concise review, we highlighted the few examples advocated regarding the use of dendrimers to deliver CNS drugs directly via IN. This review highlighed the few examples of the association of dendrimer encapsulating drugs (e.g., small compounds: haloperidol and paeonol; macromolecular compounds: dextran, insulin and calcitonin; and siRNA) using IN administration. Good efficiencies were observed. In addition, we will present the in vivo effects of PAMAM dendrimers after IN administration, globally, showing no general toxicity.

An in vitro mechanistic approach towards understanding the distinct pathways regulating insulin resistance and adipogenesis by apocynin

Adipogenesis is a cascade of processes that entail the differentiation of fibroblasts into mature adipocytes, which results in the accumulation of triglycerides in the adipose cells due to high dietary supplements. This physiological condition increases the risk of type 2 diabetes. Apocynin (4-hydroxy-3-methoxyacetophenone), an organic compound from the root extracts of the medicinal herb Picrorhiza kurroa, has been used in various experimental studies. The current study focuses on deciphering the cellular and molecular mechanisms interlinking obesity and diabetes by validating the various key targets involved in insulin signaling and adipogenesis. Apocynin exhibited enhanced glucose uptake and decreased lipid accumulation in the adipocytes. Furthermore, the expression of molecular markers involved in the insulin signaling pathway, such as IRTK, IRS-1, PI3K, GLUT-4, and the adipogenic pathway, such as PPAR α, adiponectin, C/EBP-α and SREBP1C, by qPCR supported our hypothesis largely. Apocynin mimicked insulin in the insulin-signaling pathway by showing equivalent gene expression. It ameliorated adipogenesis by downregulating the key markers in the adipogenic pathway. Corroborating the hypothesis that Apocynin is antihyperlipidemic in nature, it reduced the expression of PPARα and adiponectin. These results substantiate that Apocynin exerts anti-diabetic and anti-adipogenic effects by regulating resistin and antioxidant enzyme levels in vitro.

Rotational Spectroscopy Meets Quantum Chemistry for Analyzing Substituent Effects on Non-Covalent Interactions: The Case of the Trifluoroacetophenone-Water Complex

The most stable isomer of the 1:1 complex formed by 2,2,2-trifluoroacetophenone and water has been characterized by combining rotational spectroscopy in supersonic expansion and state-of-the-art quantum-chemical computations. In the observed isomer, water plays the double role of proton donor and acceptor, thus forming a seven-membered ring with 2,2,2-trifluoroacetophenone. Accurate intermolecular parameters featuring one classical O-H···O hydrogen bond and one weak C-H···O hydrogen bond have been determined by means of a semi-experimental approach for equilibrium structure. Furthermore, insights on the nature of the established non-covalent interactions have been unveiled by means of different bond analyses. The comparison with the analogous complex formed by acetophenone with water points out the remarkable role played by fluorine atoms in tuning non-covalent interactions.

Enzyme-Inspired Assembly: Incorporating Multivariate Interactions to Optimize the Host-Guest Configuration for High-Speed Enantioselective Catalysis

To achieve a rapid asymmetry conversion, the substrate objects suffer from accelerated kinetic velocity and random rotation at the cost of selectivity. Inspired by natural enzymes, optimizing the host-guest configuration will realize the high-performance enantioselective conversion of chemical reactions. Herein, multivariate binding interactions were introduced into the 1D channel of a chiral catalyst to simulate the enzymatic action. An imidazolium group was used to electrophilically activate the C═O unit of a ketone substrate, and the counterion binds the hydrogen donor isopropanol. This binding effect around the catalytic center produces strong stereo-induction, resulting in high conversion (99.5% yield) and enantioselectivity (99.5% ee) for the asymmetric hydrogenation of biomass-derived acetophenone. In addition, the turnover frequency of the resulting catalyst (5160 h^-1 TOF) is more than 58 times that of a homogeneous Ru-TsDPEN catalyst (88 h^-1 TOF) under the same condition, which corresponds to the best performance reported till date among all existing catalysts for the considered reaction.

An improved and highly selective fluorescence assay for measuring phosphatidylserine decarboxylase activity

Phosphatidylserine decarboxylases (PSDs) catalyze the conversion of phosphatidylserine (PS) to phosphatidylethanolamine (PE), a critical step in membrane biogenesis and a potential target for development of antimicrobial and anti-cancer drugs. PSD activity has typically been quantified using radioactive substrates and products. Recently, we described a fluorescence-based assay that measures the PSD reaction using distyrylbenzene-bis-aldehyde (DSB-3), whose reaction with PE produces a fluorescence signal. However, DSB-3 is not widely available and also reacts with PSD's substrate, PS, producing an adduct with lower fluorescence yield than that of PE. Here, we report a new fluorescence-based assay that is specific for PSD and in which the presence of PS causes only negligible background. This new assay uses 1,2-diacetyl benzene/β-mercaptoethanol, which forms a fluorescent iso-indole-mercaptide conjugate with PE. PE detection with this method is very sensitive and comparable with detection by radiochemical methods. Model reactions examining adduct formation with ethanolamine produced stable products of exact masses (m/z) of 342.119 and 264.105. The assay is robust, with a signal/background ratio of 24, and can readily detect formation of 100 pmol of PE produced from Escherichia coli membranes, Candida albicans mitochondria, or HeLa cell mitochondria. PSD activity can easily be quantified by sequential reagent additions in 96- or 384-well plates, making it readily adaptable to high-throughput screening for PSD inhibitors. This new assay now enables straightforward large-scale screening for PSD inhibitors against pathogenic fungi, antibiotic-resistant bacteria, and neoplastic mammalian cells.

Tyrosinase-Targeting Gallacetophenone Inhibits Melanogenesis in Melanocytes and Human Skin-Equivalents

Demands for safe depigmentation compounds are constantly increasing in the pharmaceutical and cosmetic industry, since the numerous relevant compounds reported to date have shown undesirable side effects or low anti-melanogenic effects. In this study, we reported three novel inhibitors of tyrosinase, which is the key enzyme in melanogenesis, identified using docking-based high throughput virtual screening of an in-house natural compound library followed by mushroom tyrosinase inhibition assay. Of the three compounds, gallacetophenone showed high anti-melanogenic effect in both human epidermal melanocytes and a 3D human skin model, MelanoDerm. The inhibitory effect of gallacetophenone on tyrosinase was elucidated by computational molecular modeling at the atomic level. Binding of gallacetophenone to the active site of tyrosinase was found to be stabilized by hydrophobic interactions with His367, Ile368, and Val377; hydrogen bonding with Ser380 and a water molecule bridging the copper ions. Thus, our results strongly suggested gallacetophenone as an anti-melanogenic ingredient that inhibits tyrosinase.

Uncovering matrix effects on lipid analyses in MALDI imaging mass spectrometry experiments

The specific matrix used in matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) can have an effect on the molecules ionized from a tissue sample. The sensitivity for distinct classes of biomolecules can vary when employing different MALDI matrices. Here, we compare the intensities of various lipid subclasses measured by Fourier transform ion cyclotron resonance (FT-ICR) IMS of murine liver tissue when using 9-aminoacridine (9AA), 5-chloro-2-mercaptobenzothiazole (CMBT), 1,5-diaminonaphthalene (DAN), 2,5-Dihydroxyacetophenone (DHA), and 2,5-dihydroxybenzoic acid (DHB). Principal component analysis and receiver operating characteristic curve analysis revealed significant matrix effects on the relative signal intensities observed for different lipid subclasses and adducts. Comparison of spectral profiles and quantitative assessment of the number and intensity of species from each lipid subclass showed that each matrix produces unique lipid signals. In positive ion mode, matrix application methods played a role in the MALDI analysis for different cationic species. Comparisons of different methods for the application of DHA showed a significant increase in the intensity of sodiated and potassiated analytes when using an aerosol sprayer. In negative ion mode, lipid profiles generated using DAN were significantly different than all other matrices tested. This difference was found to be driven by modification of phosphatidylcholines during ionization that enables them to be detected in negative ion mode. These modified phosphatidylcholines are isomeric with common phosphatidylethanolamines confounding MALDI IMS analysis when using DAN. These results show an experimental basis of MALDI analyses when analyzing lipids from tissue and allow for more informed selection of MALDI matrices when performing lipid IMS experiments.

Paeonol alleviates primary dysmenorrhea in mice via activating CB2R in the uterus

BACKGROUND AND PURPOSE

Primary dysmenorrhea is the most common gynaecologic problem in menstruating women and is characterized by spasmodic uterine contraction and pain symptoms associated with inflammatory disturbances. Paeonol is an active phytochemical component that has shown anti-inflammatory and analgesic effects in several animal models. The aim of this study was to explore whether paeonol is effective against dysmenorrhea and to investigate the potential mechanism of cannabinoid receptor signalling.

EXPERIMENTAL APPROACH

Dysmenorrhea was established by injecting oestradiol benzoate into female mice. The effects of paeonol on writhing time and latency, uterine pathology and inflammatory mediators were explored. Isolated uterine smooth muscle was used to evaluate the direct effect of paeonol on uterine contraction.

KEY RESULTS

The oral administration of paeonol reduced dysmenorrhea pain and PGE2 and TNF-α expression in the uterine tissues of mice, and paeonol was found to be distributed in lesions of the uterus. Paeonol almost completely inhibited oxytocin-, high potassium- and Ca²⁺-induced contractions in isolated uteri. Antagonists of CB2R (AM630) and the MAPK pathway (U0126), but not of CB1R (AM251), reversed the inhibitory effect of paeonol on uterine contraction. Paeonol significantly blocked L-type Ca²⁺ channels and calcium influx in uterine smooth muscle cells via CB2R. Molecular docking results showed that paeonol fits well with the binding site of CB2R.

CONCLUSIONS AND IMPLICATIONS

Paeonol partially acts through CB2R to restrain calcium influx and uterine contraction to alleviate dysmenorrhea in mice. These results suggest that paeonol has therapeutic potential for the treatment of dysmenorrhea.

Asymmetric Transfer Hydrogenation of Arylketones Catalyzed by Enantiopure Ruthenium(II)/Pybox Complexes Containing Achiral Phosphonite and Phosphinite Ligands

A family of complexes of the formula trans-[RuCl₂(L)(R-pybox)] (R-pybox = (S,S)-ⁱPr-pybox, (R,R)-Ph-pybox, L = monodentate phosphonite, PPh(OR)₂, and phosphinite, L = PPh₂(OR), ligands) were screened in the catalytic asymmetric transfer hydrogenation of acetophenone, observing a strong influence of the nature of both the R-pybox substituents and the L ligand in the process. The best results were obtained with complex trans-[RuCl₂{PPh₂(OEt)}{(R,R)-Ph-pybox}] (2c), which provided high conversion and enantioselectivity (up to 96% enantiomeric excess, e.e.) for the reduction of a variety of aromatic ketones, affording the (S)-benzylalcohols.

Ultrasound and Radiation-Induced Catalytic Oxidation of 1-Phenylethanol to Acetophenone with Iron-Containing Particulate Catalysts

Iron-containing particulate catalysts of 0.1–1 µm size were prepared by wet and ball-milling procedures from common salts and characterized by FTIR, TGA, UV-Vis, PXRD, FEG-SEM, and XPS analyses. It was found that when the wet method was used, semi-spherical magnetic nanoparticles were formed, whereas the mechanochemical method resulted in the formation of nonmagnetic microscale needles and rectangles. Catalytic activity of the prepared materials in the oxidation of 1-phenylethanol to acetophenone was assessed under conventional heating, microwave (MW) irradiation, ultrasound (US), and oscillating magnetic field of high frequency (induction heating). In general, the catalysts obtained by wet methods exhibit lower activities, whereas the materials prepared by ball milling afford better acetophenone yields (up to 83%). A significant increase in yield (up to 4 times) was observed under the induction heating if compared to conventional heating. The study demonstrated that MW, US irradiations, and induction heating may have great potential as alternative ways to activate the catalytic system for alcohol oxidation. The possibility of the synthesized material to be magnetically recoverable has been also verified.

Targeting cellular microtubule by phytochemical apocynin exhibits autophagy-mediated apoptosis to inhibit lung carcinoma progression and tumorigenesis

BACKGROUND

Lung cancer is the leading cause of cancer-related deaths worldwide. Several targets have been identified for lung cancer therapy, amongst which 'Microtubule' and its dynamics are the most widely studied and used in therapy. Tubulin-microtubule polymer dynamics are highly sought after targets in the field of anti-cancer drug designing. Natural compounds are important sources for developing anticancer therapeutics owing to their efficacy and lower cytotoxicity. Evidence suggested that therapeutic targeting of microtubule by natural compounds is amongst the most widely used interventions in numerous cancer therapies including lung cancer.

PURPOSE

To determine the efficacy of apocynin (a natural compound) in suppressing the progression of lung carcinoma both in vitro and in vivo, along with the identification of targets and the underlying mechanism for developing a novel therapeutic approach.

METHODS

We have demonstrated themicrotubule depolymerizing role of apocynin by established protocols in cellular and cell-free system. The efficacy of apocynin to inhibit lung carcinoma progression was studied on A549 cells.The tumoricidal ability of apocynin was studied in BALB/c mice model as well.Mice were classified into 4 groups namely-group II mice as tumor control; group III-IV mice asalso tumor-induced but treated with differential apocynin doses whereas group I mice were kept as normal.

RESULTS

Apocynin, showed selective cytotoxicity towards lung cancer cells rather than normal lung fibroblast cells. Apocynin inhibited oncogenic properties including growth, proliferation (p < 0.05), colony formation (p < 0.05), invasion (p < 0.05) and spheroid formation (p < 0.05) in lung cancer cells. Apart from other established properties, apocynin was found to be a novel and potent component to bind with tubulin and depolymerize cellular microtubule network. Apocynin mediated cellular microtubule depolymerization was the driving mechanism to trigger autophagy-mediated apoptotic cell death (p < 0.05) which in turn retarded lung cancer progression. Furthermore, apocynin showed tumoricidal characteristics to inhibit lung tumorigenesis in mice as well.

CONCLUSION

Targeting tubulin-microtubule equilibrium with apocynin could be the key regulator to catastrophe cellular catabolic processes to mitigate lung carcinoma. Thus, apocynin could be a potential therapeutic agent for lung cancer treatment.

Electrochemical characteristics of the decolorization of three dyes by laccase mediator system (LMS) with synthetic and natural mediators

Laccase mediator system (LMS), a very attractive candidate for refractory organics biodegradation, harbors tremendous potential on industry application. However, the performance of LMS usually varies with the discrepancy of mediators and substrates in their chemical structures. Here, we adopt electrochemical analysis that is able to assess the degradation performance of various LMS on three different dyes by quantitative analysis of reaction outcome. Two mechanisms were suggested to explain the grafting of three mediators (1-Hydroxybenzotriazole, Violuric Acid and Acetosyringone), involving the transformation of proton or electron to produce active moieties, which subsequently react with target substrates. A thorough electrochemical insight into the redox features of mediators and its change in the presence of laccase and substrates were carried out using electrochemical analysis. The effectiveness of each kind of LMS on substrates was preliminarily evaluated by analyzing the change of the peak current and potential of mediators. The actual conversion rate of dyes was used to verify the analysis results, which confirms the important role of the stability of the oxidized form as well as their redox potential of the mediators in determining the mechanism of substrate oxidation. The application of electrochemical analysis in efficiency evaluation of LMS shed new light on effective selection of suitable mediators for degradation of refractory organics. It was therefore possible to prejudge the efficacy of LMS by analyzing the electrochemical parameters of target substances and mediators, which undoubtedly has broad further application prospects of LMS.

Prenylated Acetophloroglucinol Dimers from Acronychia trifoliolata: Structure Elucidation and Total Synthesis

The isolation of 12 secondary metabolites, including seven new acetophenone monomers, from the 50% CH₃OH/CH₂Cl₂ extract (N089419-L/6) of Acronychia trifoliolata was reported previously. In the present work, three new prenylated acetophenone dimers (1-3) and five known dimers (4-8) were isolated, and their structures were elucidated by using various NMR spectroscopic techniques and HRMS. Among the new dimers, an unprecedented 4-isobutyl-3-isopropyltetrahydro-2H-pyran ring was observed in the structure of 1. This study is the first to report the formation of a 2H-pyran ring between two prenylated acetophloroglucinols. Only four related dimers have been reported before, and they were formylated phloroglucinol dimers from the family Eucalypteae. Compounds 2 and 3 are acrovestone-like dimers, and the structure of 3 was confirmed by total synthesis. The evaluation of the antiproliferative activity of isolated and synthesized acrovestone-like dimers indicated that a double bond in the prenyl-like moiety as found in the more active compounds might be important for mediating activity, while the pendant isobutyl group seems to be less important.

Transient UV-vis absorption spectroscopic characterisation of 2'-methoxyacetophenone as a DNA photosensitiser

2'-Methoxyacetophenone (2M) presents improved UVA absorption as compared with other acetophenone derivatives. On the basis of transient infrared spectroscopy it has been previously claimed that 2M is an interesting photosensitiser for cyclobutane pyrimidine dimers (CPDs) formation. In the present paper, a complete UV-Vis transient absorption spectroscopic characterisation of this compound is provided, including triplet-triplet spectra, triplet lifetimes and rate constants for quenching of 2M by a dimeric thymine derivative. Furthermore, generation of singlet oxygen has been proven by time-resolved near IR phosphorescence measurements. Overall, the obtained results confirm the potential of 2M as a DNA photosensitiser, not only for CPDs formation, but also for oxidative damage.

Synthesis of 6,12-Disubstituted Methanodibenzo[b,f][1,5]dioxocins: Pyrrolidine Catalyzed Self-Condensation of 2′-Hydroxyacetophenones

The preparation of unprecedented 6,12-disubstituted methanodibenzo[b,f][1,5]dioxocins from pyrrolidine catalyzed self-condensation of 2′-hydroxyacetophenones is herein described. This method provides easy access to this highly bridged complex core, resulting in construction of two C–O and two C–C bonds, a methylene bridge and two quaternary centers in a single step. The intricate methanodibenzo[b,f][1,5]dioxocin compounds were obtained in up to moderate yields after optimization of the reaction conditions concerning solvent, reaction times and the use of additives. Several halide substituted methanodibenzo[b,f][1,5]dioxocins could be prepared from correspondent 2′-hydroxyacetophenones.

Isolation, Chiral-Phase Resolution, and Determination of the Absolute Configurations of a Complete Series of Stereoisomers of a Rearranged Acetophenone with Three Stereocenters

A synthesis-inspired chemical investigation of the leaves of Melicope ptelefolia led to the isolation of evodialones A-D (1-4), four rearranged acetophenone stereoisomers possessing a prenylated acylcyclopentenone skeleton with three stereogenic carbons. Evodialones C and D (3 and 4) are new minor constituents. The chiral-phase HPLC resolution gave (+)-1-4 and (-)-1-4, eight enantiomers forming a complete stereoisomer library. Their absolute configurations were elucidated via extensive spectroscopic data and a modified Mosher's method. The relationship between the chiral structures and their NMR and ECD data is discussed. Compounds (±)-1, -2, and -4 have significant protective effects on high-glucose-induced oxidative stress in human vein endothelial cells.

The Mosaic of Rottlerin: The Sequel

Rottlerin (1) is a potent protein kinase C δ inhibitor that possesses a wide range of biological activities. However, the potential of this molecule to be developed as a drug has been restricted by its limited availability. We report herein a gram scale quantity synthesis of rottlerin in a five-step synthetic route that can be completed within 2 days. The methodology was extended by the reaction of the key aminochromene intermediate (15) with various electron-rich arenes, forming novel unsymmetrical methylene-bridged compounds. The X-ray crystal structure revealed the boomerang shape of this kind of molecule for the first time. The direct transformation of rottlerin (1) into the natural product, isorottlerin (35), was observed for the first time, and we named this transformation the "isorottlerin change". In addition, the antibacterial activities of rottlerin (1) and new rottlerin analogues 32-34 were examined against Staphylococcus aureus. The compounds showed MIC values as low as 2.0 μM, which were comparable to the clinically used antibiotic gentamicin.

Rottlerin Reduces cAMP/CREB-Mediated Melanogenesis via Regulation of Autophagy

Melanogenesis is the sequential process of melanin production by melanocytes in order to protect the skin from harmful stimuli. Melanogenesis is disrupted by radiation exposure, which results in the differentiation of melanocytes into melanoma. Recently, some methods have been developed to maintain the instability of melanogenesis in melanoma by activating cellular autophagy. However, there is still a lack of knowledge about how autophagy is involved in the regulation of melanogenesis in melanoma cells. Here, we used rottlerin as an autophagy inducer to investigate the role of the cyclic adenosine monophosphate (cAMP)/cAMP response element binding (CREB) signaling pathway in melanogenesis. We found that rottlerin can inhibit melanin production by targeting cAMP, which is initially activated by alpha-melanocyte stimulating hormone (α-MSH). Our findings suggest that rottlerin has a pivotal role as an autophagy inducer in the regulation of melanogenesis by targeting the cAMP/CREB signaling pathway.

An Improved Method for the Quaternization of Nicotinamide and Antifungal Activities of Its Derivatives

The quaternization reactions of nicotinamide, with different electrophiles: methyl iodide and substituted 2-bromoacetophenones (4-Cl, 4-Br, 4-H, 4-CH₃, 4-F, 4-OCH₃, 4-Ph, 2-OCH₃, 4-NO₂) are reported. The preparations were carried out by conventional synthesis and under microwave irradiation in absolute ethanol and acetone. The synthesis performed by microwave dielectric heating significantly improved yield, up to 8 times, and shortened down the reaction time from ca. one day in conventional, to 10⁻20 min. The structures of the synthesized compounds were confirmed by IR, ¹H- and ¹³C-NMR spectroscopy, mass spectrometry and elemental analysis. The compounds have been screened for antifungal activities against Fusarium oxysporum, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiorum at concentrations of 10 µg/mL and 100 µg/mL. Six compounds showed the strong inhibition of mycelium growth at a concentration of 10 µg/mL. All tested compounds revealed the great inhibitory activities against S. sclerotiorum at a concentration of 100 µg/mL.

Stainless Steel Wire Mesh Supported Molecularly Imprinted Composite Membranes for Selective Separation of Ebracteolata Compound B from Euphorbia fischeriana

Stainless steel wire mesh supported molecularly imprinted composite membranes for selective separation of Ebracteolata Compound B (ECB) were prepared based on surface polymerization using ECB separated from Euphorbia fischeriana as a template, acrylamide as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, azodiisobutyronitrile as an initiator, and stainless steel wire mesh as support. Structure and purity of ECB were characterized by nuclear magenetic resonance (¹H-NMR, 13C-NMR) and ultra high performance liquid chromatography (UHPLC). The molecularly imprinted composite membranes were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). The membrane adsorbed on the ECB reached equilibrium about 30 min later, with a maximum adsorption amount of 3.39 μmol/cm². Adsorption behavior between ECB and the molecularly imprinted composite membranes followed pseudo-second-order kinetics equation and Freundlich isotherm model. The molecularly imprinted composite membranes that could selectively identify and transport ECB in similar structures have a permeation rate of 38.71% to ECB. The ECB content in the permeation solution derived from the extract of Euphorbia fischeriana through the imprinted membrane was 87%. Overall, the obtained results demonstrated that an efficient approach with the molecularly imprinted composite membranes for selective separation of ECB from Euphorbia fischeriana.

Hits-to-Lead Optimization of the Natural Compound 2,4,6-Trihydroxy-3-geranyl-acetophenone (tHGA) as a Potent LOX Inhibitor: Synthesis, Structure-Activity Relationship (SAR) Study, and Computational Assignment

A new series of 2,4,6-trihydroxy-3-geranyl-acetophenone (tHGA) analogues were synthesized and evaluated for their lipoxygenase (LOX) inhibitory activity. Prenylated analogues 4a⁻g (half maximal inhibitory concentration (IC50) values ranging from 35 μ M to 95 μ M) did not exhibit better inhibitory activity than tHGA (3a) (IC50 value: 23.6 μ M) due to the reduction in hydrophobic interaction when the alkyl chain length was reduced. One geranylated analogue, 3d, with an IC50 value of 15.3 μ M, exhibited better LOX inhibitory activity when compared to tHGA (3a), which was in agreement with our previous findings. Kinetics study showed that the most active analogue (3e) and tHGA (3a) acted as competitive inhibitors. The combination of in silico approaches of molecular docking and molecular dynamic simulation revealed that the lipophilic nature of these analogues further enhanced the LOX inhibitory activity. Based on absorption, distribution, metabolism, excretion, and toxicity (ADMET) and toxicity prediction by komputer assisted technology (TOPKAT) analyses, all geranylated analogues (3a⁻g) showed no hepatotoxicity effect and were biodegradable, which indicated that they could be potentially safe drugs for treating inflammation.

Significantly Accelerated Osteoblast Cell Growth on TiO2/SrHA Composite Mediated by Phenolic Compounds (BHM) from Hippocamp us kuda Bleeler

The microstructure of hydroxyapatite is known to influence cellular behavior, can be used as a substrate for osteoblast growth, and exploited as a drug-release platform. However, easy delamination and self-decomposition of hydroxyapatite caused by poor adhesion with substrates are the main problems currently. In this paper, we successfully fabricated titanium dioxide/strontium-doped hydroxyapatite (TiO₂/SrHA) composite scaffolds by self-generated strontium-substituted hydroxyapatite microspheres in TiO₂ nanotubes. Moreover, the active compound 1-(5-bromo-2-hydroxy-methoxyphenyl)-ethanone (BHM) from Seahorse ( Hippocampus kuda Bleeler) was loaded in this scaffold, and the controlled release kinetics of BHM was studied. It was found that in the first 5 h, the release concentration and time of BHM had a good linear relationship, and the correlation coefficient reached 0.98. TiO₂/SrHA/BHM composites exhibited favorable cytocompatibility at a given concentration of BHM (20 μmol/L). Compared to pure SrHA, TiO₂ nanotubes, and traditional TiO₂/SrHA composites, superior cytocompatibility (cell adhesion and proliferation) of MC3T3-E1 was obtained on TiO₂/SrHA/BHM composites. The expression levels of osteogenic marker genes such as alkaline phosphatase, osteopontin, osteocalcin, runt-related transcription factor 2, and collagen I are also upregulated to varying degrees. This TiO₂/SrHA composite scaffold-mediated phenolic compound BHM could be applied in bone tissue repair.

Surface modification of sludge-derived carbon by phosphoric acid as new electrocatalyst for degradation of acetophenone

Sludge-derived carbons (SCs) were modified by different acids and used as electrocatalyst for electrochemical oxidation degradation of acetophenone. The results showed that SC treated with phosphoric acid (H₃PO₄-SC) exhibited the highest catalytic activity. The degradation efficiency of acetophenone reached 87.0%, and TOC removal was 72.3% under the conditions of 100 mg L^-1 acetophenone, 90 mA cm^-2, and 180 min reaction time. The element content and chemical state of H₃PO₄-SC were measured by XRF, XRD, TGA, FTIR, and Mössbauer spectra, and the results indicated that ferric iron and phosphate on the surface of H₃PO₄-SC might play the main role in acetophenone degradation. The carbonyl-¹³C-labeled acetophenone was first used to investigate the degradation of acetophenone in electrochemical oxidation by NMR.

A New Pathway for the Synthesis of a New Class of Blue Fluorescent Benzofuran Derivatives

In this study an efficient and straightforward method for obtaining a new class of blue fluorescent bezofuran derivatives, under microwave irradiation, as well as under conventional thermal heating, is presented. Under conventional TH the reactions occur selectively, and a single type of benzofuran ester derivative was obtained. The synthesis under MW irradiation also led to benzofuran derivatives, but in a time-dependent manner. Irradiation for a short period of time led to a mixture of two types of benzofuran derivatives (3a⁻c and 4a⁻c), while MW irradiation for a longer period of time led to a single type of benzofuran (3-methylbenzofuran), the reaction becoming highly selective. Taking into consideration the advantages offered by MW irradiation in terms of a substantial decrease of solvent consumed, a substantial reduction in reaction time (from days to hours), and a consequent diminution in energy consumption, these methods could be considered environmentally friendly. Here, feasible reaction mechanisms for the benzofuran derivatives formation are described. The absorption and fluorescence emission of the obtained benzofuran derivatives were studied, with part of these compounds being intense blue emitters. A certain influence of the benzofuran substituents concerning absorption and fluorescent properties was observed. Only compounds anchored with a carbomethoxy group of furan ring have shown good quantum yields.

The Protective Effects of a Synthetic Geranyl Acetophenone in a Cellular Model of TNF-α-Induced Pulmonary Epithelial Barrier Dysfunction

Alveolar epithelial barrier dysfunction contributes to lung edema and can lead to acute lung injury (ALI). The features include increased epithelial permeability, upregulation of inflammatory mediators and downregulation of junctional complex molecules; these changes are often induced by inflammation. tHGA is an acetophenone analogue with therapeutic potential in asthma. Its therapeutic potential in ALI is presently unknown. Herein, the effects of tHGA on epithelial barrier dysfunction were determined in TNF-α-induced human alveolar epithelial cells. The anti-inflammatory properties of tHGA were assessed by monocyte adhesion assay and analysis of MCP-1 and ICAM-1 expression. The epithelial barrier function was assessed by paracellular permeability and transepithelial electrical resistance (TEER) assays, and analysis of junctional complex molecules expression. To elucidate the mechanism of action, the effects of tHGA on the NF-κB and MAPK pathways were determined. Gene and protein expression were analyzed by RT-PCR and Western blotting or ELISA, respectively. tHGA suppressed leukocyte adhesion to TNF-α-induced epithelium and reduced MCP-1 and ICAM-1 gene expression and secretion. tHGA also increased TEER readings, reduced epithelial permeability and enhanced expression of junctional complex molecules (zona occludens-1, occludin and E-cadherin) in TNF-α-induced cells. Correspondingly, the NF-κB, ERK and p38 MAPK pathways were also inhibited by tHGA. These findings suggest that tHGA is able to preserve alveolar epithelial barrier function in response to acute inflammation, via its anti-inflammatory activity and stabilization of epithelial barrier integrity, mediated by NF-κB, ERK and p38 MAPK signaling.

Hypouricemic Effect of 2,5-Dihydroxyacetophenone, a Computational Screened Bioactive Compound from Ganoderma applanatum, on Hyperuricemic Mice

Searching novel hypouricemic agents of high efficacy and safety has attracted a great attention. Previously, we reported the hypouricemic effect of Ganoderma applanatum, but its bioactives, was not referred. Herein, we report the hypouricemic effect of 2,5-dihydroxyacetophenone (DHAP), a compound screened from Ganoderma applanatum computationally. Serum parameters, such as uric acid (SUA), xanthine oxidase (XOD) activity, blood urea nitrogen (BUN), and creatinine were recorded. Real-time reverse transcription PCR (RT-PCR) and Western blot were exploited to assay RNA and protein expressions of organic anion transporter 1 (OAT1), glucose transporter 9 (GLUT9), uric acid transporter 1 (URAT1), and gastrointestinal concentrative nucleoside transporter 2 (CNT2). DHAP at 20, 40, and 80 mg/kg exerted excellent hypouricemic action on hyperuricemic mice, reducing SUA from hyperuricemic control (407 ± 31 μmol/L, p < 0.01) to 180 ± 29, 144 ± 13, and 139 ± 31 μmol/L, respectively. In contrast to the renal toxic allopurinol, DHAP showed some kidney-protective effects. Moreover, its suppression on XOD activity, in vivo and in vitro, suggested that XOD inhibition may be a mechanism for its hypouricemic effect. Given this, its binding mode to XOD was explored by molecular docking and revealed that three hydrogen bonds may play key roles in its binding and orientation. It upregulated OAT1 and downregulated GLUT9, URAT1, and CNT2 too. In summary, its hypouricemic effect may be mediated by regulation of XOD, OAT1, GLUT9, URAT1, and CNT2.

Suzuki-Miyaura Coupling of Simple Ketones via Activation of Unstrained Carbon-Carbon Bonds

Here, we describe that simple ketones can be efficiently employed as electrophiles in Suzuki-Miyaura coupling reactions via catalytic activation of unstrained C-C bonds. A range of common ketones, such as cyclopentanones, acetophenones, acetone and 1-indanones, could be directly coupled with various arylboronates in high site-selectivity, which offers a distinct entry to more functionalized aromatic ketones. Preliminary mechanistic study suggests that the ketone α-C-C bond was cleaved via oxidative addition.

Syntheses of 1-Aryl-5-nitro-1H-indazoles and a General One-Pot Route to 1-Aryl-1H-indazoles

An efficient route to substituted 1-aryl-1H-indazoles has been developed and optimized. The method involved the preparation of arylhydrazones from acetophenone or benzaldehyde substituted by fluorine at C2 and nitro at C5, followed by deprotonation and nucleophilic aromatic substitution (S_NAr) ring closure in 45–90%. Modification of this procedure to a one-pot domino process was successful in the acetophenone series (73–96%), while the benzaldehyde series (63–73%) required a step-wise addition of reagents. A general one-pot protocol for 1-aryl-1H-indazole formation without the limiting substitution patterns required for the S_NAr cyclization has also been achieved in 62–78% yields. A selection of 1-aryl-1H-indazoles was prepared in high yield by a procedure that requires only a single laboratory operation.

Preliminary Quality Evaluation and Characterization of Phenolic Constituents in Cynanchi Wilfordii Radix

A new phenolic compound, 2-O-β-laminaribiosyl-4-hydroxyacetophenone (1), was isolated from Cynanchi Wilfordii Radix (CWR, the root of Cynanchum wilfordii Hemsley), along with 10 known aromatic compounds, including cynandione A (2), bungeisides-C (7) and –D (8), p-hydroxyacetophenone (9), 2′,5′-dihydroxyacetophenone (10), and 2′,4′-dihydroxyacetophenone (11). The structure of the new compound (1) was elucidated using spectroscopic methods and chemical methods. The structure of cynandione A (2), including a linkage mode of the biphenyl parts that remained uncertain, was unambiguously confirmed using the 2D ¹³C–¹³C incredible natural abundance double quantum transfer experiment (INADEQUATE) spectrum. Additionally, health issues related to the use of Cynanchi Auriculati Radix (CAR, the root of Cynanchum auriculatum Royle ex Wight) instead of CWR have emerged. Therefore, constituents present in methanolic extracts of commercially available CWRs and CARs were examined using UV-sensitive high-performance liquid chromatography (HPLC), resulting in common detection of three major peaks ascribed to cynandione A (2), p-hydroxyacetophenone (9), and 2′,4′-dihydroxyacetophenone (11). Thus, to distinguish between these ingredients, a thin-layer chromatography (TLC) method, combined with only UV irradiation detection, focusing on wilfosides C1N (12) and K1N (13) as marker compounds characteristic of CAR, was performed. Furthermore, we propose this method as a simple and convenient strategy for the preliminary distinction of CWR and CAR to ensure the quality and safety of their crude drugs.

Deuterium-Labeling Studies Reveal the Mechanism of Cytochrome P450-Catalyzed Formation of 2-Aminoacetophenone from 3-Methylindole (Skatole) in Porcine Liver Microsomes

2-Aminoacetophenone, a product of the hepatic 3-methylindole (skatole) clearance in pigs, contributes to the specific aroma of fat from tainted boar meat. Surprisingly, high formation rates for 2-aminoacetophenone from skatole in microsomal preparations from Pietrain × Baden-Württemberg hybrid type boars have been previously demonstrated, but the mechanism of this cytochrome P450-mediated reaction remained unknown. Therefore, microsomal fractions from boars were incubated with deuterium-labeled skatole and with possible reaction intermediates. 3-Methyloxindole and 3-hydroxy-3-methyloxindole were identified as degradation products of skatole en route to 2-aminoacetophenone. Additionally, the labeling studies provided further evidence for a cytochrome P450-mediated lyase reaction that leads to the cleavage of the indole heterocyclic ring system in 3-hydroxy-3-methyloxindole and demonstrated the involvement of several cytochrome P450-isoforms by employing isotopically sensitive branching experiments.

Multi-Component One-Pot Reaction of Aromatic Carbonyl Compounds, Tosylhydrazide, and Arylboronic Acids

In this paper, we developed a new method using 4-bromoacetophenone as the starting material, with tosylhydrazide and two arylboronic acids using Barluenga and Suzuki couplings in a four-component one-pot reaction to afford the target product 4-benzyl-1,1′-biphenyls. This system that we have developed enables the use of easily accessible starting materials and can be employed on a wide variety of substrates with good functional group tolerance. In particular, this protocol can be applied to the synthesis of 4-(1-([1,1′-biphenyl]-4-yl)ethyl)pyridine derivatives, a class of potential analogs of CPY17 inhibitors of prostate cancer.

Multifunctional protein microparticles for medical applications

Micro- and nano-scale intelligent devices can revolutionize the medical field. Although proteins are promising materials for creating biocompatible miniature medical devices with biological functions, construction of complicated solid-state architectures, using inherently vulnerable proteins, remains challenging. Here, I present a sophisticated strategy for constructing a multifunctional microparticle for medical applications using multiple proteins; this strategy achieved the retention of function, increased stability, and orientation control of the proteins in the fabricated particle. As proof-of-concept, the particle, designed to cope with excess reactive oxygen species (ROS) involved in many diseases, was constructed by combining three proteins with different functions. The body of the particle was fabricated using albumin and superoxide dismutase (SOD), and the antibody was incorporated into the surface of the particle in an orientation-controlled manner. The constructed protein microparticle exhibited coordinated activities for coping with ROS, such as capture of the ROS-secreting cells by the incorporated antibody, followed by the elimination of 70% ROS, secreted from the captured cells, by the SOD in the particle. Additionally, diapocynin, loaded to the particle via the drug-binding ability of albumin, was released from the particle, preventing ROS production in the cells. This multifunctional microparticle, constructed from proteins, will profoundly impact the development of intelligent protein-based miniature devices used in medical fields.

New approach for the quantification of metallic species in healthcare products based on optical switching of a Schiff base possessing ONO donor set

A new method is reported for the quantification of some metallic components of healthcare products utilizing a Schiff base chelator derived from 2-hydroxyacetophenone and ethanolamine. The Schiff base chelator recognizes some metallic species such as iron, copper and zinc (important components of some healthcare products), and cadmium (common contaminant in healthcare products) giving colorimetric/fluorimetric response. It coordinates with Fe²⁺/Fe³⁺ and Cu²⁺ ions via ONO donor set and switches the colour to bright red, green and orange, respectively. Similarly, it switches 'ON' a fluorometric response when coordinates with Zn²⁺ and Cd²⁺ ions. In the present approach, detailed studies on the colorimetric and fluorimetric response of ONO Schiff base is investigated in detail. The Job plot for the complexation of ONO switch with various metal ions suggested formation of 1:1 (metal-chelator) complex with Fe²⁺, Fe³⁺, and Cu²⁺ while 1:2 (metal-chelator) for Zn²⁺ and Cd²⁺ ions. The limit of detection, limit of quantification are 6.73, 18.0, 25.0, 0.65, 1.10μM and 27.0, 72.0, 100.0, 2.60 and 4.40μM for Fe²⁺, Fe³⁺, Cu²⁺, Zn²⁺ and Cd²⁺ ions, respectively. Under the optimized conditions, chelator was used for the quantification of important metals present in healthcare products via direct dissolution and furnace treatment during sample preparation. The results were found precise and accurate for both sample preparation techniques using the developed method.

Evaluation of LPS-Induced Acute Lung Injury Attenuation in Rats by Aminothiazole-Paeonol Derivatives

Paeonol is a key phenolic compound in the root bark of Moutan Cortex Radicis that has been used in traditional Chinese Medicine to ameliorate inflammation. A series of aminothiazole-paeonol derivatives (APDs) were synthesized in this work and subjected to preliminary evaluation in cells followed by verification in animals. Quantification of monocyte chemotactic protein-1 (MCP-1) and interleukin-6 (IL-6) in culture media of LPS-activated A549 cells, a lung epithelial adenocarcinoma cell line, were used to investigate the anti-inflammatory capability of APDs. ALI-bearing rats were employed to verify therapeutic efficacy of APDs according to observations of total cells, protein amounts, MCP-1 and IL-6 in bronchoalveolar lavage fluid (BALF). Histopathological examinations of lung tissues were consequently applied for validation of APDs. Among these compounds, 2-(2-aminothiazol-4-yl)-5-methoxyphenol (4) had the most potent activity, showing comparable inhibition of MCP-1/IL-6 and superior elimination of neutrophil infiltration and protein exudation in lungs compared to others as well as dexamethasone. This study demonstrated a comprehensive strategy to evaluate APDs through integration of cell-based screening and animal-based verification. In order to fulfill unmet needs of treating acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), APDs introduced in this work could be promising lead compounds to develop high potent anti-inflammation agents.

Statin and rottlerin small-molecule inhibitors restrict colon cancer progression and metastasis via MACC1

MACC1 (Metastasis Associated in Colon Cancer 1) is a key driver and prognostic biomarker for cancer progression and metastasis in a large variety of solid tumor types, particularly colorectal cancer (CRC). However, no MACC1 inhibitors have been identified yet. Therefore, we aimed to target MACC1 expression using a luciferase reporter-based high-throughput screening with the ChemBioNet library of more than 30,000 compounds. The small molecules lovastatin and rottlerin emerged as the most potent MACC1 transcriptional inhibitors. They remarkably inhibited MACC1 promoter activity and expression, resulting in reduced cell motility. Lovastatin impaired the binding of the transcription factors c-Jun and Sp1 to the MACC1 promoter, thereby inhibiting MACC1 transcription. Most importantly, in CRC-xenografted mice, lovastatin and rottlerin restricted MACC1 expression and liver metastasis. This is-to the best of our knowledge-the first identification of inhibitors restricting cancer progression and metastasis via the novel target MACC1. This drug repositioning might be of therapeutic value for CRC patients.

Influence of Dimerization of Apocynin on Its Effects in Experimental Colitis

Apocynin has been widely used as an inhibitor of the nicotinamide adenine dinucleotide phosphate oxidase (NADPH-oxidase) system and shows promise as an anti-inflammatory drug. Diapocynin, the dimeric product generated by the oxidation of apocynin in the presence of myeloperoxidase (MPO), is supposed to be its active form. In this study, diapocynin has been chemically synthesized and its activity on several inflammatory mediators in LPS-stimulated RAW 264.7 macrophages and its anti-inflammatory effect on ulcerative colitis induced by dextran sodium sulfate (DSS) in mice analyzed. We found that diapocynin showed higher inhibitory activity than apocynin. The dimer reduced ROS production, TNF-α, IL-6, and IL-1β levels and inhibited iNOS and COX-2 expression as well as decreased NO and PGE₂ production induced in LPS-stimulated RAW 264.7 cells. The anti-inflammatory molecular mechanism of diapocynin was associated with the suppression of NF-κB activation. However, these results were not paralleled by in vivo studies. Oral administration of apocynin and diapocynin (100 mg/kg) three times a week exhibited similar protections against experimental inflammatory bowel disease induced by DSS; therefore, apocynin should not be considered a prodrug. However, it should be taken into account that the dimer is more potent because its dose (0.3 mmol/kg) is half that of apocynin.