N-substituted benzamides inhibit nuclear factor-kappaB and nuclear factor of activated T cells activity while inducing activator protein 1 activity in T lymphocytes

N,N′-(Ethane-1,2-diyl)bis(2-chlorobenzamide)

The title compound, C16H14Cl2N2O2, crystallized with one half-molecule in the asymmetric unit; the whole molecule is generated by inversion symmetry, the center of inversion being situated at the middle of the bridging –CH2—CH2– bond. The dihedral angle between the amide group and the benzene ring is 52.4 (2)°. In the crystal, molecules are linked by two pairs of N—H...O hydrogen bonds forming a ladder-like structure propagating along thea-axis direction and enclosingR22(14) ring motifs. The compound was refined as a two-component twin [BASF = 0.18 (1)].

5-Aminosalicylic Acid Azo-Linked to Procainamide Acts as an Anticolitic Mutual Prodrug via Additive Inhibition of Nuclear Factor kappaB

To improve the anticolitic efficacy of 5-aminosalicylic acid (5-ASA), a colon-specific mutual prodrug of 5-ASA was designed. 5-ASA was coupled to procainamide (PA), a local anesthetic, via an azo bond to prepare 5-(4-{[2-(diethylamino)ethyl]carbamoyl}phenylazo)salicylic acid (5-ASA-azo-PA). 5-ASA-azo-PA was cleaved to 5-ASA and PA up to about 76% at 10 h in the cecal contents while remaining stable in the small intestinal contents. Oral gavage of 5-ASA-azo-PA and sulfasalazine, a colon-specific prodrug currently used in clinic, to rats showed similar efficiency in delivery of 5-ASA to the large intestine, and PA was not detectable in the blood after 5-ASA-azo-PA administration. Oral gavage of 5-ASA-azo-PA alleviated 2,4,6-trinitrobenzenesulfonic acid-induced rat colitis. Moreover, combined intracolonic treatment with 5-ASA and PA elicited an additive ameliorative effect. Furthermore, combined treatment with 5-ASA and PA additively inhibited nuclear factor-kappaB (NFκB) activity in human colon carcinoma cells and inflamed colonic tissues. Finally, 5-ASA-azo-PA administered orally was able to reduce inflammatory mediators, NFκB target gene products, in the inflamed colon. 5-ASA-azo-PA may be a colon-specific mutual prodrug acting against colitis, and the mutual anticolitic effects occurred at least partly through the cooperative inhibition of NFκB activity.

2-Methyl-N-p-tolyl-benzamide: a second monoclinic polymorph

The title compound, C₁₅H₁₅NO, (I), is a polymorph of the structure (II) reported by Gowda et al. [Acta Cryst. (2008), E64, o1494]. Compound (II) crystalllizes in the space group C2/c (Z = 8), whereas the title compound occurs in space group P2₁/c (Z = 4). The two mol­ecular structures differ slightly in the relative orientations of their central amide group with respect to the benzoyl ring [dihedral angles of 55.99 (7) for (I) and 59.96 (11)° for (II)] and in the inclination of the benzoyl and aniline rings [88.67 (8) for (I) and 81.44 (5)° for (II)]. In the crystal structure of (I), mol­ecules are linked by N—H⋯O hydrogen bonds, forming C(4) chains, which are augmented by weak C—H⋯O inter­actions. The structure is further stabilized by C—H⋯π contacts involving both of the aromatic rings.

N-(4-Nitro-phen-yl)cinnamamide

In the mol-ecule of the title compound, C(15)H(12)N(2)O(3), the dihedral angle between the rings is 3.04 (8)°. The central NOC(3) fragment is planar [maximum deviation = 0.005 (3) Å] and is oriented at dihedral angles of 8.23 (8) and 7.29 (9)° with respect to the phenyl and nitro-phenyl rings, respectively. In the crystal structure, inter-molecular N-H⋯O and C-H⋯O inter-actions link the mol-ecules into a two-dimensional network. π-π contacts between rings [centroid-centroid distance = 3.719 (1) Å] may further stabilize the structure.

4-Chloro-N-(2,6-dichloro-phen-yl)benzamide

The title compound, C₁₃H₈Cl₃NO, crystallizes with four mol­ecules in the asymmetric unit. In the mol­ecular structure, the conformations of the central amide –CONH group show a wide range of dihedral angles with respect to the attached aromatic rings (benzoyl and anilino). The dihedral angles between the amide group and the benzoyl ring are 8.1 (3), 4.3 (3), 27.8 (1) and 32.7 (2)° in the four mol­ecules. The amide group is twisted out of the plane of the anilino ring, as shown by the dihedral angles of 85.4 (1), 74.3 (1), 88.1 (1) and 77.6 (1)° in the four mol­ecules. The aromatic rings are oriented at dihedral angles of 86.6 (1), 78.0 (1), 60.3 (1) and 69.8 (1)° in the four mol­ecules. The crystal structure is stabilized via inter­molecular N—H⋯O hydrogen bonds, aromatic aromatic inter­actions, short Cl⋯Cl contacts and C—H⋯Cl hydrogen bonds. Inter­molecular hydrogen bonds connect the mol­ecules into two distinct chains running along the c axis of the crystal. One mol­ecule forms an inversion dimer in which the main inter­actions are π–π stacking [centroid–centroid distances = 3.749 (1) and 3.760 (1) Å] and a short Cl⋯Cl contact of 3.408 (1) Å.

4-Chloro-N-cyclo-hexyl-benzamide

In the title compound, C₁₃H₁₆ClNO, the cyclo­hexyl ring adopts a chair conformation, with puckering parameters Q = 0.576 (3) Å, θ = 0.1 (3) and ϕ = 8 (15)°. In the crystal structure, inter­molecular N—H⋯O hydrogen bonds link mol­ecules into one-dimensional chains propagating in [010].

4-Chloro-N-m-tolylbenzamide

In the title compound, C₁₄H₁₂ClNO, the dihedral angle between the two aromatic rings is 11.29 (15)°. The crystal packing is stabilized by N—H⋯O hydrogen bonds linking the mol­ecules into chains running along the c axis.

N-Butyl-4-chloro-benzamide

In the title benzamide derivative, C(11)H(14)ClNO, the chloro-benzene and butyl-amine groups are each planar, with mean deviations from the planes of 0.013 and 0.030 Å, respectively, and a dihedral angle of 2.54 (9)° between the two planes. In the crystal structure, N-H⋯O hydrogen bonds link mol-ecules in rows along a. Short inter-molecular Cl⋯Cl inter-actions [3.4225 (5) Å] link these rows into sheets in the ac plane. Additional weak C-H⋯O and C-H⋯π inter-actions generate a three-dimensional network.

N-substituted 4-aminobenzamides (procainamide analogs): an assessment of multiple cellular effects concerning ion trapping

Procainamide and related triethylamine-substituted 4-aminobenzamides, such as metoclopramide and declopramide, exert cellular effects potentially exploitable in oncology at millimolar concentrations (DNA demethylation, nuclear factor-kappaB inhibition, apoptosis) and display anti-inflammatory properties. However, these drugs induce massive cell vacuolization at similar concentrations, a response initiated by vacuolar (V-) ATPase-dependent ion trapping into and osmotic swelling of acidic organelles. We have examined whether this overlooked response might be related to the effects on cell proliferation and viability using cultured vascular smooth muscle cells and tumor-derived cell lines (Morris 7777 hepatoma, HT-1080 fibrosarcoma). Giant vacuole formation, of confirmed trans-Golgi origin (labeled with C5-ceramide, p230, golgin-97), is a cellular response to all tested amines in the series (> or = 2.5 mM), including triethylamine. These drugs and the V-ATPase inhibitor bafilomycin A1 inhibited smooth muscle cell proliferation, suggesting that acidification of a cellular compartment is essential to cell division. The cytotoxicity was maximal with metoclopramide, and this effect was minimally influenced by bafilomycin A1; furthermore, metoclopramide (2.5 mM) induced apoptosis in tumor cells as judged by poly(ADP-ribose)polymerase (PARP) cleavage. Triethylamine and procainamide exhibit a low level of cytotoxicity variably reduced by bafilomycin co-treatment. In Morris cells, the secretion of alpha-fetoprotein is inhibited by amines, consistent with the impairment of the secretory pathway. The most highly substituted 4-aminobenzamides are significant NF-kappaB inhibitors in smooth muscle cells. Although some effects of 4-aminobenzamides are independent of V-ATPase-driven ion trapping (inhibition of NF-kappaB nuclear translocation, agent-specific cytotoxicity, PARP cleavage), other effects are dependent on this phenomenon (vacuolization, a component of the cytotoxicity, inhibition of secretion).

A new pharmacological effect of salicylates: inhibition of NFAT-dependent transcription

The anti-inflammatory effects of salicylates, originally attributed to inhibition of cyclooxygenase activity, are currently known to involve additional mechanisms. In this study we investigated the possible modulation by salicylates of NFAT-mediated transcription in lymphocytic and monocytic cell lines. RNase protection assays showed that 2-acetoxy-4-trifluoromethylbenzoic acid (triflusal) inhibited, in a dose-dependent manner, mRNA expression of several cytokine genes, most of which are NFAT-regulated and cyclosporin A (CsA)-sensitive. In Jurkat cells, the expression of IL-3, GM-CSF, TNF-alpha, TGF-beta1, IL-2, lymphotactin, MIP-1alpha, and MIP-1beta was inhibited to different extents. In THP-1 cells, inhibition of the expression of M-CSF, G-CSF, stem cell factor, IFN-gamma, TNF-alpha, TGF-beta1, lymphotoxin-beta1, MIP-1alpha, MIP-1beta, and IL-8 was observed. Sodium salicylate and aspirin only showed significant effects at 5 mM. The transcriptional activity of two genes that contain NFAT sites, a GM-CSF full promoter and a T cell-specific enhancer from the IL-3 locus, was also inhibited by salicylates. Transactivation experiments performed with several NFAT-dependent and AP-1-dependent reporter genes showed that triflusal strongly inhibited NFAT-dependent transcription at concentrations as low as 0.25 mM. Sodium salicylate and aspirin were less potent. The triflusal inhibitory effect was reversible and synergized with suboptimal doses of CsA. Experiments to address the mechanism of action of salicylates in the NFAT activation cascade disclosed a mechanism different from that of CsA, because salicylates inhibited DNA-binding and NFAT-mediated transactivation without affecting phosphorylation or subcellular localization of NFAT. In summary, these data describe a new pharmacological effect of salicylates as inhibitors of NFAT-dependent transcription.

Differential expression of proteins in rat plasma exposed to benzene

Benzene, a ubiquitous environmental contaminant, is an important solvent in the chemical industry and is also known as a constituent of petroleum. It has been reported that benzene is associated with hematotoxicity including leukemia in humans and cancer in laboratory animals. To study protein expression alterations in rat plasma exposed to benzene, rats were exposed to levels of 1, 10, 100 ppm benzine for 6 h/day and 5 d/week for 2 or 6 weeks. Two-dimensional gel electrophoresis of rat plasma was carried out, and approximately 1000 protein spots were detected on the gels. The 11 spots which showed significantly different expression were selected and identified with matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. Analyzing the targeted 11 spots, there was no correlation between the 2 and 6 weeks benzene-inhaled groups on up-regulated proteins (zinc finger protein, and tristetraprolin) and on down-regulated proteins (cAMP-regulated guanine nucleotide exchange factor II, protein kinase and unknown protein). The overexpressed proteins (inhibitor of kappaB-like protein, GTP-binding protein rab14, T-cell receptor alpha chain, and somatostatin transactivating factor-1) were detected only in groups inhaling benzene for 6 weeks. Among them the expression level of T-cell receptor alpha chain was confirmed by Western blot.

Differential usage of IkappaBalpha and IkappaBbeta in regulation of apoptosis versus gene expression

In this study we use the N-substituted benzamides declopramide (3-CPA) and N-acetyl declopramide (Na-3-CPA) to investigate the involvement of the transcription factor NF-kappaB in the induction of apoptosis and surface immunoglobulin kappa (Igkappa) expression in the mouse pre-B cell line 70Z/3. We first showed that 3-CPA-induced apoptosis at doses around 500 microM and that the 3-CPA-induced apoptosis could be suppressed by over-expression of the Bcl-2 protein. Na-3-CPA was shown to be non-apoptotic at doses up to 1-2 mM. On the other hand, Na-3-CPA inhibited LPS-induced Igkappa expression while 3-CPA had no effect. Further analysis showed that while 3-CPA inhibited breakdown of IkappaBalpha, Na-3-CPA inhibited breakdown of IkappaBbeta. In addition, we used a 70Z/3 cell line expressing a dominant negative IkappaBalpha (70Z/3(deltaNIkappaBalpha)). The 70Z/3(deltaNIkappaBalpha) cell line was shown to be more sensitive to apoptosis and cytotoxicity induced by 3-CPA as well as by LPS, probably due to a defect in NF-kappaB rescue mechanism. Taken together, our data implicate distinct roles for IkappaBalpha and IkappaBbeta in regulating various NF-kappaB activities.

Arylamine N-acetyltransferases and drug response

Arylamine N-acetyltransferases (NATs) play an important role in the interaction of competing metabolic pathways determining the fate of and response to xenobiotics as therapeutic drugs, occupational chemicals and carcinogenic substances. Individual susceptibility for drug response and possible adverse drug reactions are modulated by the genetic predisposition (manifested for example, by polymorphisms) and the phenotype of these enzymes. For all drugs metabolized by NATs, the impact of different in vivo enzyme activities is reviewed with regard to therapeutic use, prevention of side effects and possible indications for risk assessment by phenotyping and/or genotyping. As genes of NATs are susceptibility genes for multifactorial adverse effects and xenobiotic-related diseases, risk prediction can only be made possible by taking the complexity of events into consideration.

Mechanism of action for N-substituted benzamide-induced apoptosis

We have analysed the mechanism of action for induction of apoptosis by N-substituted benzamides using declopramide as a lead compound. We show here that declopramide at doses above 250 microM in the mouse 70Z/3 pre-B cell line or in the human promyeolocytic cancer cell line HL60 induced cytochrome c release into the cytosol and caspase-9 activation. The broad spectrum caspase inhibitor zVADfmk and caspase-9 inhibitor zLEDHfmk inhibited apoptosis and improved cell viability when administrated to cells 1 h before exposure to declopramide, whereas the caspase-8 inhibitor zIEDHfmk had less effect. Also, the over expression of Bcl-2 by transfection in 70Z/3 cells inhibited declopramide-induced apoptosis. Prior to the induction of apoptosis, a G(2)/M cell cycle block was induced by declopramide. The cell cycle block was also observed in the presence of broad spectrum caspase inhibitor zVADfmk and in a transfectant expressing high levels of Bcl-2. Furthermore, while p53 was induced in 70Z/3 cells by declopramide, neither the apoptotic mechanism nor the G(2)/M cell cycle block were dependent on p53 activation since both effects were also seen in p53 deficient HL60 cells after addition of declopramide.