Antiinflammatory benzimidazole derivative with inhibitory effects on neutrophil function.

5-Methyl-2,2,2-trifluoroethylsulfonyl-1H-benzimidazole (BI-L-45 XX) inhibits both neutrophil enzyme release and chemotaxis in vitro and also inhibits chemotaxis in vivo. BI-L-45 XX has an IC50 between 16 microM and 25 microM in inhibiting lysosomal enzyme release from human peripheral blood neutrophils. In a Boyden chamber experiment, BI-L-45 XX inhibited migration in response to fMLP with an IC50 of 5 microM. When given orally to passively sensitized rats at doses of 0.1 to 1.0 mg/kg, it inhibited migration of neutrophils to the pleural cavity in response to an antigen (ovalbumin) challenge. BI-L-45 XX also shows activity in the developing adjuvant arthritis model, with an ED50 of 45 mg/kg, while exhibiting no significant inhibition of cyclooxygenase in a human platelet assay. This suggests the possibility that its antiinflammatory activity may be in part mediated by its effect on neutrophil function.

Pharmacological modulation of plasminogen activator secretion by P388D1 cell line.

P388D1 is a murine macrophage cell line which spontaneously secretes plasminogen activator (PA; activated function) and lysozyme (LYS; constitutive function). Compounds which decrease PA secretion without affecting LYS secretion have potential as "down-regulators" of macrophage function and, hence, of the immune system. Glucocorticoids (e.g., dexamethasone, IC50 less than 0.01 microM) and auranofin (IC50 = 1 microM) are positive in this model. In contrast, cyclooxygenase inhibitors (indomethacin, ibuprofen and piroxicam, all at 1 microM) boost PA secretion; lipoxygenase inhibitors (REV-5901, NDGA and piriprost, all at 10 microM) have little or no effect. Dexamethasone, but not auranofin, induces a urokinase-inhibitory activity which elutes between 0.13 and 0.19 M NaCl upon anion exchange HPLC (TSK-DEAE-5-PW). Fibrin overlay following SDS-PAGE of the HPLC peak reveals a urokinase-inhibitory band at approximately 90 Kd.

Benzimidazole derivatives with atypical antiinflammatory activity.

A number of substituted 2-[(2,2,2-trifluoroethyl)sulfonyl]-1H-benzimidazoles (4) have demonstrated antiinflammatory activity that appears to have a mechanism distinct from typical cyclooxygenase inhibiting nonsteroidal antiinflammatory drugs. Several of these compounds inhibit adjuvant-induced arthritis in rats at 25 mg/kg while showing no activity in the carrageenan paw edema model at up to 100 mg/kg. Two compounds, 4a and 4b, showed no significant inhibition of cyclooxygenase in vitro at concentrations as high as 5 X 10(-5) M. All compounds 4 active in adjuvant-induced arthritis were also found to inhibit release of lysosomal enzymes from neutrophils, raising the possibility that their antiinflammatory effect is at least partially mediated by an effect on neutrophil function.

Tissue distribution and excretion in urine, feces and respiratory CO2 of [14C]-ciclosidomine in beagle dogs.

14C-Labelled N-cyclohexanecarbonyl-3-(4-morpholino)-sydnone-imine hydrochloride [( 14C]-ciclosidomine, Neopres) labelled in the sydnone or morpholine position was administered orally and by intravenous injection to beagle dogs at a dose level of 1 mg/kg. The rates and routes of excretion of radioactivity were determined. The oral dose was completely absorbed and most (greater than 70%) of the radioactive label (both positions) was excreted in the urine within the first 24-48 h. The remaining label(morpholine-labelled drug) was found in feces (less than or equal to 8%), respiratory 14CO2 (2.3%) and throughout the carcass, with no major single depot. Radioactivity peaked within four hours. Elimination of dose label from the blood was biphasic, with an alpha phase (t 1/2 of 2.5 and 4.6 h after oral administration of morpholine- and sydnone-labelled drug, respectively) and a very slow beta-phase (t 1/2 = 120 h, both labels). Thin layer chromatography of 0-24 h urines (morpholine label) indicated total metabolism of the parent compound. A device is described for the continuous monitoring over several days of 14CO2 in exhaled breath from a conscious dog.

Rapid identification of Enterobacteriaceae with microbial enzyme activity profiles.

A total of 539 clinical isolates belonging to 10 species of the Enterobacteriaceae family were identified by enzyme activity profiles within 30 min of test inoculation. Each isolate was grown at 37 degrees C for 18 h on Mueller-Hinton agar and suspended to an optical density of 200 Klett units on 0.85% saline. Enzyme activity profiles were obtained by inoculating 18 fluorogenic substrates with the standardized bacterial suspension and monitoring initial rates of hydrolysis over the first 30 min of analysis. Individual enzyme activity profiles were entered into a coded data bank, and identifications were based on the Bayesian theory of probabilities. At a confidence level of 95%, five species were identified with a greater than 90% efficiency, three species were identified between 83 and 88% efficiency, and two species demonstrated a 72 and 75% efficiency of identification. The enzyme activity profile method of bacterial identification is rapid, easily automated, and reproducible.