Publications by authors named "Antonio M Bonin"

Background: The ability of Zn(II) and Cu(II) metal complexes of non-steroidal anti-inflammatory drugs (NSAIDs) to inhibit acute arterial inflammation in vivo has been studied.

Results: When acute vascular inflammation was induced in normocholesterolemic New Zealand White rabbits by inserting a non-occlusive silastic collar around the common carotid artery, a single oral dose of Cu(II)-indomethacin (Cu(II)Indo, 3 mg/kg) administered by laparotomy achieved a 67 % (8.2 ± 1.

View Article and Find Full Text PDF

N-Acyloxy-N-alkoxyamides (see structure 1, below) are direct-acting mutagens for which a QSAR has been established that predicts with accuracy their activity in the bacterial reverse-mutation assay (Ames test) in Salmonella typhimurium TA100. Steric bulk next to oxygen on the alkoxyl side-chain in structure 4 has no impact on activity, but branching at the position adjacent (alpha) to the ester-carbonyl of the leaving group in structure 5 strongly inhibits mutagenicity. Both results reflect the manner in which these molecules interact with DNA.

View Article and Find Full Text PDF

Purpose: To evaluate, for the first time, the efficacy of copper-indomethacin in the inhibition of aberrant crypt foci formation using the azoxymethane-induced adenocarcinoma model, to examine cell viability in the HCT-116 colorectal cancer cell line, gastrointestinal permeability, mitochondrial oxidative damage, and renal toxicity in rat models.

Methods: Azoxymethane-induced adenocarcinoma rats were dosed with indomethacin and copper-indomethacin for 28 days and aberrant crypt foci were evaluated. HCT-116 colorectal cancer cells were exposed to indomethacin and copper-indomethacin at 0-250 microg/mL (0-698 microM for indomethacin, and 0-147 microM for copper-indomethacin), and cell viability was measured.

View Article and Find Full Text PDF

Electrophilic N-acyloxy-N-alkoxyamides are mutagenic in Salmonella typhimurium TA100 without the need for S9 metabolic activation and they react with DNA at guanine-N7 at physiological pH. Since these are direct-acting mutagens, structural factors influence binding and reactivity with DNA. Mutagenicity in TA100 can be predicted by a QSAR incorporating hydrophobicity (logP), stability to substitution reactions at nitrogen (pK(a) of the leaving acid) and steric effects of para-aryl substituents (E(s)).

View Article and Find Full Text PDF

Acetonitrile extracts of ulcerated and control rat stomachs were studied by various NMR techniques in an attempt to understand how indomethacin, a common and powerful nonsteroidal antiinflammatory drug (NSAID), induces ulcers in the stomach. One- (1D) and two-dimensional (2D) NMR spectra of extracts of ulcerated and control stomachs revealed that glycolytic and Krebs cycle enzymes were partially inhibited in the ulcerated stomach as shown by the lactate/glucose ratio. The (total choline)/lactate ratio was also higher in the extract from the control stomach than in the ulcerated stomach.

View Article and Find Full Text PDF

N-Acyloxy-N-alkoxyamides are anomeric amides that are direct-acting mutagens. They have been shown to damage DNA in the major and the minor grooves in a pH and sequence-selective manner. In acidic media, they damage adenines at N3 in the minor groove but above neutral pH, only guanine is damaged at N7 in the major groove.

View Article and Find Full Text PDF