Benzimidazole drugs and modulation of biotransformation enzymes

Novel Benzimidazole-Oxadiazole Derivatives as Anticancer Agents with VEGFR2 Inhibitory Activity: Design, Synthesis, In Vitro Anticancer Evaluation, and In Silico Studies

The aim of this research is the synthesis of benzimidazole-1,3,4-oxadiazole derivatives that could be potential anticancer leads inhibiting VEGFR2. The compounds were evaluated for their cytotoxicity against cancer cell lines PANC-1, MCF-7, and A549 using the MTT assay. Two different normal cell lines (hTERT-HPNE and CCD-19Lu) were used to calculate the selectivity indices of the compounds. Compound 4r showed the highest anticancer activities, with IC50 = 5.5, 0.3, and 0.5 μM against the PANC-1, A549, and MCF-7 cell lines, respectively. Also, compounds 4r and 4s were further evaluated for their inhibitory activity against VEGFR2. VGFRA immunolocalizations of compounds 4r and 4s were visualized by the VEGFA immunofluorescent staining method. Molecular docking studies have proven that, as in sorafenib, compounds 4r and 4s show hydrogen bond formation with Asp1046 and Cys919 and hydrophobic interactions with other active site amino acids. Molecular dynamics simulations were carried out for compounds 4r and 4s to examine the stability and behavior of the protein-ligand complex obtained from molecular docking under in silico physiological conditions. An in silico ADME investigation was undertaken to confirm the druglikeness of the synthesized compounds. Furthermore, the stable geometries of the ligands were determined through the application of density functional theory (DFT). The optimized geometries were confirmed to correspond to true minima, as no imaginary frequencies were observed in the vibration frequency survey. The rotations of the thio and benzimidazole groups with respect to the 1,3,4-oxadiazole rings are 180 deg, and the molecules are planar.

Design, synthesis, and biological evaluation of novel imidazole derivatives as analgesic and anti-inflammatory agents: experimental and molecular docking insights

Imidazole moieties exhibit a broad range of biological activities, including analgesic, anti-depressant, anticancer, anti-fungal, anti-tubercular, anti-inflammatory, antimicrobial, antiviral, and antifungal properties. In this study, we explored the use of Schiff base for the synthesis of new imidazole derivatives as anti-inflammatory and pain-relieving agents. A series of eight novel imidazole analogues (2a-h) were prepared in three steps with excellent yields. All compounds were characterized using IR, NMR, and mass spectral data. Their analgesic and anti-inflammatory activities were evaluated using hot plate and paw oedema methods. Compound 2 g (1-(2,3-dichlorophenyl)-2-(3-nitrophenyl)-4,5-diphenyl-1H-imidazole) showed significant analgesic activity (89% at 100 mg/kg b.w.), while compounds 2a (2-(2,6-dichlorophenyl)-1-(4-ethoxyphenyl)-4,5-diphenyl-1H-imidazole) and 2b (2-(2,3-dichlorophenyl)-1-(2-chlorophenyl)-4,5-diphenyl-1H-imidazole) exhibited good anti-inflammatory activity (100% at 100 mg/kg b.w.), comparable to diclofenac salt (100% at 50 mg/kg b.w.). Molecular docking studies were conducted using Schrödinger software version 2021-2, employing the OPLS4 force field for both receptor and ligand preparation. The results were visualized using molecular visualization software such as PyMOL. These studies revealed that compound 2g exhibited the highest binding affinity with the COX-2 receptor (-5.516 kcal/mol). Compound 2g formed three conventional hydrogen bonds with residues GLN-242 (bond length: 2.3 Å) and ARG-343 (bond lengths: 2.2 Å & 2.4 Å). This binding affinity was comparable to that of Diclofenac salt, which showed the highest binding affinity of -5.627 kcal/mol with the COX-2 receptor. Diclofenac salt formed two conventional hydrogen bonds with the residues ARG-344 (bond length: 2.0 Å) and TRP-140 (bond length: 1.7 Å). Later, molecular dynamic simulations confirmed the stable binding affinity of compound 2g with the protein. Furthermore, other compounds also demonstrated potential binding to the receptor-binding pocket region. The anti-inflammatory potential of the synthesized compounds was evaluated using the carrageenan-induced rat hind paw oedema model, while the analgesic potential was assessed using the hot plate method. These evaluations were conducted in comparison with Diclofenac sodium, serving as the standard compound. However, compound 2g stood out for its superior analgesic activity, as confirmed by in-vivo examination. These findings suggest that these novel imidazole derivatives have potential as anti-inflammatory and analgesic agents.

Activation of the aryl hydrocarbon receptor improves allergen-specific immunotherapy of murine allergic airway inflammation: a novel adjuvant option?

Background

Allergen-specific immunotherapy (AIT) is able to restore immune tolerance to allergens in allergic patients. However, some patients do not or only poorly respond to current treatment protocols. Therefore, there is a need for deeper mechanistic insights and further improvement of treatment strategies. The relevance of the aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, has been investigated in several inflammatory diseases, including allergic asthma. However, its potential role in AIT still needs to be addressed.

Methods

A murine model of AIT in ovalbumin-induced allergic airway inflammation was performed in AhR-deficient (AhR-/-) and wild-type mice. Furthermore, AIT was combined with the application of the high-affinity AhR agonist 10-chloro-7H-benzimidazo[2,1-a]benzo[de]iso-quinolin-7-one (10-Cl-BBQ) as an adjuvant to investigate the effects of AhR activation on therapeutic outcome.

Results

Although AhR-/- mice suffer stronger allergic responses than wild-type mice, experimental AIT is comparably effective in both. Nevertheless, combining AIT with the administration of 10-Cl-BBQ improved therapeutic effects by an AhR-dependent mechanism, resulting in decreased cell counts in the bronchoalveolar fluid, decreased pulmonary Th2 and Th17 cell levels, and lower sIgE levels.

Conclusion

This study demonstrates that the success of AIT is not dependent on the AhR. However, targeting the AhR during AIT can help to dampen inflammation and improve tolerogenic vaccination. Therefore, AhR ligands might represent promising candidates as immunomodulators to enhance the efficacy of AIT.

Exploring precision-cut liver slices for comparative xenobiotic metabolism profiling in swine and cattle

In vitro systems are useful tools for unravelling species differences in xenobiotic metabolism.The current work aimed to validate the technique of precision-cut liver slices (PCLS) for comparative studies on xenobiotic metabolism in swine and cattle.PCLS from swine (n = 3) and cattle (n = 3) were produced using a Brendel-VitronTM Tissue Slicer and cultured for 6 h. Tissue viability was preserved throughout the whole culture period.Metabolic viability was evaluated using the anthelmintics albendazole (ABZ) and fenbendazole (FBZ) as model drugs, as well as other substrates of hepatic monooxygenases: benzydamine (BZ) N-oxygenase (FMO-dependent), and the O-dealkylations of 7-ethoxyresorufin (EROD, CYP1A1-dependent) and 7-methoxyresorufin (MROD, CYP1A2-dependent).ABZ S-oxygenation resulted 6-fold (cattle) and 13.6-fold (swine) higher (p = 0.001) compared to FBZ S-oxygenation.Similar BZ N-oxygenation and EROD activities were observed in PCLS cultures from both species. MROD was 2.5-fold higher (p = 0.033) in swine than in cattle. Similarly, ABZ S-oxygenation was 1.7-fold higher (p = 0.0002) in swine than in cattle. Conversely, a 82% higher (p = 0.0003) rate of FBZ S-oxygenation was evidenced in PCLS cultures from cattle compared to those from swine.Overall, this work shows that PCLS cultures are useful to obtain relevant information on species differences in xenobiotic metabolism.

Unravelling drug-drug interactions in pigs: Induction of hepatic cytochrome P450 1A (CYP1A) metabolism after the in-feed medication with the anthelmintic fenbendazole

The anthelmintic fenbendazole (FBZ) undergoes hepatic S‑oxygenation by monooxygenases belonging to the cytochrome P450 (CYP) and flavin-monooxygenase (FMO) families. The in-feed medication with FBZ induced CYP1A-dependent metabolism in pig liver. This fact may alter the metabolism of the anthelmintic itself, and of CYP1A substrates like aflatoxin B1 (AFB1). This work evaluated the effect of the in-feed administration of FBZ on CYP1A-dependent metabolism, on its own pattern of hepatic S‑oxygenation, and on the metabolism of AFB1. Landrace piglets remained untreated (n = 5) or received a pre-mix of FBZ (n = 6) in feed for 9 days. Pigs were slaughtered for preparation of liver microsomes used for: CYP content determination; monitoring the CYP1A-dependent enzyme activities, 7-ethoxyresorufin O-deethylase (EROD) and 7-methoxyresorufin O-demethylase (MROD); measurement of FBZ (50 μM) S‑oxygenation, and AFB1 (16 nM) disappearance from the incubation medium. In microsomes of FBZ-treated animals, EROD and MROD increased 19-fold (p = 0.002) and 14-fold (p = 0.003), respectively. An enhanced (3-fold, p = 0.004) participation of the CYP pathway in FBZ S‑oxygenation was observed in the liver of piglets treated with the anthelmintic (210 ± 69 pmol/min.nmol CYP) compared to untreated animals (68 ± 34 pmol/min.nmol CYP). AFB1 metabolism was 93% higher (p = 0.009) in the liver of FBZ-treated compared to untreated pigs. Positive and significant (p < 0.05) correlations were observed between CYP1A-dependent enzyme activities and FBZ or AFB1 metabolism. The sustained administration of FBZ caused an auto-induction of the CYP1A-dependent S‑oxygenation of this anthelmintic. The CYP1A induction triggered by the anthelmintic could amplify the production of AFB1 metabolites in pig liver, including the hepatotoxic AFB1-derived epoxide.+.

Identification of Photocatalytic Alkaloids from Coptidis Rhizome by an Offline HPLC/CC/SCD Approach

Natural products continue to be a valuable source of active metabolites; however, researchers of natural products are mostly focused on the biological effects, and their chemical utility has been less explored. Furthermore, low throughput is a bottleneck for classical natural product research. In this work, a new offline HPLC/CC/SCD (high performance liquid chromatography followed by co-crystallization and single crystal diffraction) workflow was developed that greatly expedites the discovery of active compounds from crude natural product extracts. The photoactive total alkaloids of the herbal medicine Coptidis rhizome were firstly separated by HPLC, and the individual peaks were collected. A suitable coformer was screened by adding it to the individual peak solution and observing the precipitation, which was then redissolved and used for co-crystallization. Seven new co-crystals were obtained, and all the single crystals were subjected to X-ray diffraction analysis. The molecular structures of seven alkaloids from milligrams of crude extract were resolved within three days. NDS greatly decreases the required crystallization amounts of alkaloids to the nanoscale and enables rapid stoichiometric inclusion of all the major alkaloids with full occupancy, typically without disorder, affording well-refined structures. It is noteworthy that anomalous scattering by the coformer sulfur atoms enables reliable assignment of absolute configuration of stereogenic centers. Moreover, the identified alkaloids were firstly found to be photocatalysts for the green synthesis of benzimidazoles. This study demonstrates a new and green phytochemical workflow that can greatly accelerate natural product discovery from complex samples.

Aromatic heterobicycle-fused porphyrins: impact on aromaticity and excited state electron transfer leading to long-lived charge separation

A new synthetic method to fuse benzo[4,5]imidazo[2,1-a]isoindole to the porphyrin periphery at the β,β-positions has been developed, and its impact on the aromaticity and electronic structures is investigated. Reactivity investigation of the fused benzoimidazo-isoindole component reveals fluorescence quenching of a zinc porphyrin (AMIm-2) upon treatment with a Brønsted acid. The reaction of the zinc porphyrin (AMIm-2) with methyl iodide initiated a new organic transformation, resulting in the ring-opening of isoindole with the formation of an aldehyde and dimethylation of the benzoimidazo component. The fused benzoimidazo-isoindole component acted as a good ligand to bind platinum(ii), forming novel homobimetallic and heterobimetallic porphyrin complexes. The fusion of benzoimidazo-isoindole on the porphyrin ring resulted in bathochromically shifted absorptions and emissions, reflecting the extended conjugation of the porphyrin π-system. Time-resolved emission and transient absorption spectroscopy revealed stable excited state species of the benzoimidazo-isoindole fused porphyrins. Zinc porphyrin AMIm-2 promoted excited state electron transfer upon coordinating with an electron acceptor, C60, generating a long-lived charge-separated state, in the order of 37.4 μs. The formation of the exceptionally long-lived charge-separated state is attributed to the involvement of both singlet and triplet excited states of AMIm-2, which is rarely reported in porphyrins.

Novel benzimidazole derivatives; synthesis, bioactivity and molecular docking study as potent urease inhibitors

BACKGROUND

Benzimidazole derivatives are widely used to design and synthesize novel bioactive compounds. There are several approved benzimidazole-based drugs on the market.

OBJECTIVES

In this study, we aimed to design and synthesize a series of novel benzimidazole derivatives 8a-n that are urease inhibitors.

METHODS

All 8a-n were synthesized in a multistep. To determine the urease inhibitory effect of 8a-n, the urease inhibition kit was used. The cytotoxicity assay of 8a-n was determined using MTT method. Molecular modelling was determined using autodock software.

RESULTS

All 8a-n were synthesized in high yield, and their structures were determined using 1H-NMR, 13C-NMR, MS, and elemental analyses. In compared to thiourea and hydroxyurea as standards (IC50: 22 and 100 µM, respectively), all 8a-n had stronger urease inhibition activity (IC50: 3.36-10.81 µM). With an IC50 value of 3.36 µM, 8e had the best enzyme inhibitory activity. On two evaluated cell lines, the MTT cytotoxicity experiment revealed that all 8a-n have IC50 values greater than 50 µM. Finally, a docking investigation revealed a plausible way of interaction between the 8e and 8d and the enzyme's active site's key residues.

CONCLUSION

The synthesized benzimidazole derivatives exhibit high activity, suggesting that further research on this family of compounds would be beneficial to finding a potent urease inhibitor.

Recent Advances in the Tandem Copper-Catalyzed Ullmann-Goldberg N-Arylation–Cyclization Strategies

N‒Aryl bond formation under copper catalysis has been playing a pivotal role and has been extensively used as a key step in the total syntheses of several therapeutic molecules. The...

In vitro study of chlorine dioxide on porcine intestinal epithelial cell gene markers

BACKGROUND

Chlorine dioxide (ClO₂ ) is an inorganic, potent biocide and is available in highly purified aqueous solution. It can be administered as an oral antiseptic in this form.

OBJECTIVES

Our aim is to determine the level of inflammatory markers and cytochrome genes expressed by enterocytes exposed to different concentrations of hyperpure chlorine dioxide solution.

METHODS

Porcine jejunal enterocyte cell (IPEC-J2) cultures were treated with the aqueous solution of hyper-pure chlorine dioxide of various concentrations. We determined the alterations in mRNA levels of inflammatory mediators, such as IL6, CXCL8/IL8, TNF, HSPA6 (Hsp70), CAT and PTGS2 (COX2); furthermore, the expression of three cytochrome genes (CYP1A1, CYP1A2, CYP3A29) were analysed by quantitative PCR method.

RESULTS

The highest applied ClO₂ concentration reduced the expression of all three investigated CYP genes. The gene expression of PTGS2 and CAT were not altered by most concentrations of ClO₂ . The expression of IL8 gene was reduced by all applied concentrations of ClO₂ . TNF mRNA level was also decreased by most ClO₂ concentrations used.

CONCLUSIONS

Different concentrations of chlorine dioxide exhibited immunomodulatory activity and caused altered transcription of CYP450 genes in porcine enterocytes. Further studies are needed to determine the appropriate ClO₂ concentration for oral use in animals.

Essential oil of Mentha pulegium induces anthelmintic effects and reduces parasite-associated oxidative stress in rodent model

Following the previous findings reported by the present authors on the anthelmintic effect of hydro-ethanolic extract of Mentha pulegium, the volatile constituents of M. pulegium are now assessed in the present study by exploring its anthelmintic and its antioxidant proprieties using in vitro and in vivo assays. Egg hatch assay (EHA) and adult worm's motility assays (AWMA) were used to assess the in vitro activity against Haemonchus. contortus. The in vivo anthelmintic potential was evaluated in mice infected with Heligmosomoides polygyrus using faecal egg count reduction (FECR) and total worm count reduction (TWCR). M. pulegium EO demonstrated 100% inhibition in the EHA at 200 μg/mL (IC50 = 56.36 μg/mL). In the AWM assay, EO achieved total worms paralysis 6 h after treatment exposure. This nematicidal effect was associated to morphological damages observed in the cuticular's worm using environmental scanning electron microscopy (ESEM). At 400 mg/kg, M. pulegium oil showed 75.66% of FECR and 80.23% of TWCR. The antioxidant potential of this plant was also monitored by several in vitro assays: total antioxidant capacity was 205.22 mg GAE/g DW, DPPH quenching effect was IC50 = 140 μg/mL, ABTS activity IC50 = 155 μg/mL and FRAP effect of 660 μg/mL. Regarding the in vivo assay, M. pulegium EO demonstrated a protective effect against oxidative stress by increasing the activity of the endogenous antioxidants (SOD, CAT and GPx) during H. polygyrus infection.

Benzylic Methylene Functionalizations of Diarylmethanes

Diarylmethanes are cardinal scaffolds by virtue of their unique structural feature including the presence of a benzylic CH2 group that can be easily functionalized to generate a variety of fascinating molecules holding immense importance in pharmaceutical, agrochemical, and material sciences. While the originally developed protocols for benzylic C-H functionalization in diarylmethanes employing base-mediated and metal-catalyzed strategies are still actively used, they are joined by a new array of metal-free conditions, offering milder and benign conditions. With the recent surge of interest towards the synthesis of functionalized diarylmethanes, numerous choices are now available for a synthetic organic chemist to transform the benzylic C-H bond to C-C or C-X bond offering the synthesis of any molecule of choice. This review highlights benzylic methylene (CH2 ) functionalizations of diaryl/heteroarylmethanes utilizing various base-mediated, transition-metal-catalyzed, and transition-metal free approaches for the synthesis of structurally diverse important organic molecules, often with a high chemo-, regio- and enantio-selectivity. This review also attempts to provide analysis of the scope and limitations, mechanistic understanding, and sustainability of the transformations.

tert-Amino Effect-Promoted Rearrangement of Aryl Isothiocyanate: A Versatile Approach to Benzimidazothiazepines and Benzimidazothioethers

A general and practical approach to benzimidazothiazepine and benzimidazothioether derivatives via an intramolecular nucleophilic addition/ring expansion rearrangement of aryl isothiocyanates promoted by the tert-amino effect has been developed. This reaction is catalyzed by low-cost camphorsulfonic acid and tolerates a broad substrate scope with complete atom economy. Structurally intriguing benzimidazothiazepine and benzimidazothioether products could be easily obtained by a simple operation in good to excellent yield (up to 98%).

Development of 2-(4-pyridyl)-benzimidazoles as PKN2 chemical tools to probe cancer

Kinases are signalling proteins which have proven to be successful targets for the treatment of a variety of diseases, predominantly in cancers. However, only a small proportion of kinases (<20%) have been investigated for their therapeutic viability, likely due to the lack of available chemical tools across the kinome. In this work we describe initial efforts in the development of a selective chemical tool for protein kinase N2 (PKN2), a relatively unexplored kinase of interest in several types of cancer. The most successful compound, 5, has a measured IC₅₀ of 0.064 μM against PKN2, with ca. 17-fold selectivity over close homologue, PKN1.

2-(3,4-Dimethoxyphenyl)-N-(4-methoxyphenyl)-1-propyl-1H-benzo[d]imidazole-5-carboxamide

2-(3,4-Dimethoxyphenyl)-N-(4-methoxyphenyl)-1-propyl-1H-benzo[d]imidazole-5-carboxamide was synthesized by the ‘one-pot’ reductive cyclization of N-(4-methoxyphenyl)-3-nitro-4-(propylamino)benzamide with 3,4-dimethoxybenzaldehyde, using sodium dithionite as a reductive cyclizing agent using DMSO as a solvent. The structure of newly synthesized compound was elucidated based on IR, 1H-NMR, 13C-NMR, and LC-MS data.

Synthesis, Antioxidant and Antiurease Activities of Some New 5,6- dichloro-2-(4-fluorobenzyl)-1H-benzimidazole Derivatives Containing Furan, Oxadiazole, Triazole and Thiadiazole Moieties

Background:

Benzimidazoles and its derivatives have been attracting interest for many years because of their biological activities. Benzimidazoles containing different heterocyclic moieties have wide range of biological activities such as antimicrobial, antioxidant, anticancer, antiviral, etc.

Methods:

In this study, some benzimidazole derivatives containing furan, oxadiazole, triazole and thiadiazole moieties have been synthesized and then evaluated for their antioxidant and antiurease activities.

Results:

The results showed that all the tested benzimidazoles indicated remarkable urease inhibitory potentials with IC50 values ranging between 0.303±0.03 to 0.591±0.08 µM.

Conclusion:

In conclusion, synthesized benzimidazole derivatives showed good antioxidant and antiurease activities. Heterocyclic groups on benzimidazole nucleus enhance the activities.

Oxibendazole induces apoptotic cell death in proliferating porcine trophectoderm and uterine luminal epithelial cells via mitochondria-mediated calcium disruption and breakdown of mitochondrial membrane potential

The well-known and effective anthelmintic oxibendazole was recently shown to have a broad spectrum of biological abilities, such as anti-cancer and anti-inflammation activities. In contrast, the mechanism of oxibendazole's anti-proliferative effect via cell signaling pathways and its role in pre-implantation has not been studied. Therefore, in this study we demonstrated the effects of oxibendazole on the proliferation of porcine trophectoderm (pTr) cells and porcine luminal epithelial (pLE) cells, a well-known in vitro model system of the fetal-maternal interface. Cell proliferation decreased in both pTr and pLE cells in response to oxibendazole, and we determined that this was modulated through intracellular cell signal transduction. Phosphorylation of ERK1/2, P90RSK, and S6 were downregulated by exposure to a 200 nM dose of oxibendazole in both types of cells, while the expression of phosphorylated JNK, AKT, and P70S6K was upregulated. Pre-treatment with a PI3K/AKT inhibitor (Wortmannin), ERK1/2 inhibitor (U0126), and JNK inhibitor (SP600125) induced the signaling interactions of these molecules, and oxibendazole co-treatment with each inhibitor resulted in even greater decreases in cell proliferation. Furthermore, intracellular and mitochondrial calcium ion accumulation was observed, which would mean that calcium ion homeostasis was disrupted, causing damage to the mitochondrial membrane potential. These deteriorated conditions ultimately led to apoptotic cell death. Taken together, the results of the present study identified that the apoptotic effect of oxibendazole on pTr and pLE cells is regulated by cell signaling pathways, and thus oxibendazole could influence the connection between the conceptus and the maternal uterus.

Proton transfer in the benzimidazolone and benzimidazolthione tautomerism process catalyzed by polar protic solvents

The tautomeric equilibrium of benzimidazolone and benzimidazolthione have been studied by the density functional theory method using the CAM-B3LYP functional together with the 6-311G(d,p) basis set. Two separate mechanisms have been investigated: a direct intramolecular transfer using the polarizable continuum model and an indirect proton transfer assisted by a molecule of solvent (C6H12, H2O, CH3OH, and H2O2). In both cases, the results obtained indicate that ketone and thione are the most stable forms. However, the enhanced height of the activation barrier for the four-center mechanisms describing the tautomerism reaction as a direct intramolecular transfer implicates a relatively disadvantaged process. The participation of a polar protic solvent molecule allows the lowering of the activation energy barrier. Potential energy profiles of keto-enol and thio-enol tautomerism assisted by methanol and water are very different. The former one describes a concerted mechanism but the latter does not because it is associated with asynchronous processes that take place during the thio-enol tautomerism.

Alteration in Inflammatory Responses and Cytochrome P450 Expression of Porcine Jejunal Cells by Drinking Water Supplements

The intestinal epithelium is the first determining barrier to the drugs administered per os. Cytochrome P450 (CYP) enzymes are substantial in the initial step of xenobiotic metabolism; therefore, intestinal CYP enzyme activities could be an important influencing factor of the oral utilization of xenobiotic substances. In this study, the effect of four drinking water supplements on CYP mRNA levels of porcine intestinal epithelial cells was examined. Further goal of the study is to describe the effect of these feed additives on the proinflammatory response of the LPS-treated enterocytes. The nontransformed porcine intestinal epithelial cells (IPEC-J2) were grown on six-well polyester membrane inserts. Cell cultures were treated with LPS (10 μg/ml), β-glucan (5 and 50 μg/ml), sanguinarine-containing additive (5 and 50 μg/ml), drinking water acidifier (0.1 and 1 μl/ml), and fulvic acid (25 and 250 μg/ml) for 1 hour. Cells were washed with culture medium and incubated for additional 1 h before total RNA isolation. IL-6, IL-8, TNF-α, HSP70, CYP1A1, CYP1A2, and CYP3A29 mRNA levels were measured. The LPS treatment upregulated the gene expression of IL-8 and TNF-α. The relative gene expression of IL-6 remained unchanged and TNF-α and HSP70 were downregulated after the treatment with each feed additive. CYP1A1 and CYP1A2 expressions increased after sanguinarine-containing solution, fulvic acid, and drinking water acidifier treatment. None of the treatments changed the gene expression of CYP3A29, responsible for the metabolism of the majority of drug substances used in swine industry. The feed additive substances inhibited the expression of proinflammatory mediators HSP70 and TNF-α; however, β-glucan and fulvic acid elevated the production of the chemokine IL-8 mRNA in endotoxin-treated enterocytes. All acidic supplements increased the expression of CYP1A1 gene; their constituents may serve as a ligand of CYP1A1 nuclear receptors.

CuI nanoparticle-catalyzed synthesis of tetracyclic benzo[e]benzo[4,5]imidazo[1,2-c][1,3]thiazin-6-imine heterocycles by SNAr-type C-S, C-N bond formation from isothiocyanatobenzenes and benzimidazoles

In this paper, a simple and practical synthesis of benzo[e]benzo[4,5]imidazo[1,2-c][1,3]thiazin-6-imine tetracyclic heterocycles via a CuI nanoparticle-catalyzed intramolecular C(sp2)-S coupling reaction is presented. This strategy provides a straightforward method for synthesizing analogs of the anti-HIV drug 3,4-dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182). The reaction rate and yield were increased by employing CuI nanoparticles.

Unprecedented chemosensing behavior of novel tetra-substituted benzimidazole zinc(II) phthalocynine for selective detection of Bi3+ ion: Synthesis, characterization and ROS generation

In this work, synthesis of novel symmetrical 4-(2-bromo-4-(5-bromo-1H-benzo[d] imidazol-2-yl) phenoxy) tetra substituted zinc phthalocyanine has been reported. The novel benzimidazole zinc phthlocynine compound (3) has been characterized by MALDI-TOF MS, FT-IR, UV-vis, and ¹H NMR spectroscopy. This new compound 3 displayed excellent selectivity towards Bi³⁺ ion in the presence of other competitive ions including Ca²⁺, Cd²⁺, Co²⁺ Cu²⁺, Fe³⁺, Hg²⁺, Sn²⁺, Mg²⁺, Na⁺, Ni²⁺ and Pb²⁺ respectively. Upon addition of Bi³⁺ into the solution of compound 3 in DMSO, dramatic change was observed in the Q- and the B-bands in UV-visible spectra as a result of donor acceptor interactions. Reactive oxygen species (ROS) were also studied using 2,7-dichlorofluorescin diacetate (DCFH-DA) a fluorescent probe which is converted to highly fluorescent dichlorofluorescein (DCF) in the presence of ROS. This property of non-aggregating zinc phthalocyanine is promising as a photosensitizer in photodynamic therapy of cancer.

In vitro and in vivo metabolite identification of a novel benzimidazole compound ZLN005 by LC-MS/MS

RATIONALE

A novel benzimidazole compound ZLN005 was previously identified as a transcriptional activator of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in certain metabolic tissues. Upregulation of PGC-1α by ZLN005 has been shown to have beneficial effect in a diabetic mouse model and in a coronary artery disease model in vitro. ZLN005 could also have therapeutic potential in neurodegenerative diseases involving down-regulation of PGC-1α. Given the phenotypic efficacy of ZLN005 in several animal models of human disease, its metabolic profile was investigated to guide the development of novel therapeutics using ZLN005 as the lead compound.

METHODS

ZLN005 was incubated with both rat and human liver microsomes and S9 fractions to identify in vitro metabolites. Urine from rats dosed with ZLN005 was used to identify in vivo metabolites. Extracted metabolites were analyzed by LC-MS/MS using a hybrid linear ion trap triple quadrupole mass spectrometer under full scan, enhanced product ion scan, neutral loss scan and precursor scan modes. Metabolites in plasma and brain of ZLN005-treated rats were also profiled using multiple reaction monitoring.

RESULTS

Identified in vitro transformations of ZLN005 include mono- and dihydroxylation, further oxidation to carboxylic acids, and mono-O-glucuronide and sulfate conjugation to hydroxy ZLN005 as well as glutathione conjugation. Identified in vivo metabolites are mainly glucuronide and sulfate conjugates of dihydroxyl, carboxyl, and hydroxy acid of the parent compound. The parent compound as well as several major phase I metabolites were found in rat plasma and brain.

CONCLUSIONS

Using both in vitro and in vivo methods, we elucidated the metabolic pathway of ZLN005. Phase I metabolites with hydroxylation and carboxylation, as well as phase II metabolites with glucuronide, sulfate and glutathione conjugation, were identified.

Sulfonated carbon-encapsulated iron nanoparticles as an efficient magnetic nanocatalyst for highly selective synthesis of benzimidazoles

Various benzimidazoles were obtained by applying sulfonated carbon-encapsulated iron nanoparticles as the nanocatalyst.

Oxibendazole inhibits prostate cancer cell growth

Prostate cancer (PCa) is one of the most common malignancies among men and is the second leading cause of cancer-associated mortality in the developed world. Androgen deprivation therapy (ADT) is the most common treatment for PCa. However, the majority of androgen-sensitive PCa patients will eventually develop resistance to ADT and the disease will become androgen-independent. There is, therefore, an immediate requirement to develop effective therapeutic techniques towards the treatment of recurrent PCa. Oxibendazole (OBZ) is an anthelmintic drug that has also shown promise in the treatment of malignancies. In the present study, the capability of OBZ to repress the growth of PCa cells was assessed in human androgen-independent PCa 22Rv1 and PC-3 cell lines. The growth of the 22Rv1 and PC-3 cell lines, as assessed with a trypan blue exclusion assay, was markedly inhibited by OBZ treatment in vitro, with half-maximal inhibitory concentration values of 0.25 and 0.64 µM, respectively. The mean size of 22Rv1 tumors in nude mice treated with OBZ (25 mg/kg/day) was 47.96% smaller than that of the control mice. Treatment with OBZ increased the expression of microRNA-204 (miR-204), as determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and the level of p53 as determined with western blotting, two well-characterized tumor suppressor genes. When miR-204 expression was knocked down by introduction of an miR-204 inhibitor, the inhibitory effect of OBZ was markedly reduced; however, when it was overexpressed, the inhibitory efficiency of OBZ was markedly higher, indicating that upregulation of miR-204 is key for the efficacy of OBZ. Additionally, OBZ was demonstrated with RT-qPCR to repress the expression of the androgen receptor, and by western blotting to reduce prostate-specific androgen in 22Rv1 cells. The results suggest that OBZ has potential for clinical use in the treatment of recurrent PCa.

Synthesis and molecular docking study of some 5,6-dichloro-2-cyclopropyl-1H-benzimidazole derivatives bearing triazole, oxadiazole, and imine functionalities as potent inhibitors of urease

A new series of benzimidazole compounds including hydrazinecarbothioamide, 1,2,4-triazole, 1,3,4-oxadiazole and imine function were synthesized starting from 5,6-dichloro-2-cyclopropyl-1H-benzimidazole. All of the benzimidazole derivatives exhibited good urease inhibitor activity. Compound 6a proved to be the most potent showing an enzyme inhibitory activity with an IC₅₀=0.06µM. Molecular docking studies were also conducted on enzyme extracted from Jack bean urease to identify the binding mode of the newly synthesized compounds.