In vitro prediction of gastrointestinal absorption of novel ß-hydroxy-ß-arylalkanoic acids using PAMPA technique.

Prediction of gastrointestinal absorption of thirteen newly synthesized ß-hydroxy-ß-arylalkanoic acids (HAA) and ibuprofen was performed using PAMPA test. The highest values of PAMPA parameters (%T and Papp) were calculated for 1C, 1B and 2C and these parameters were significantly lower in comparison to ibuprofen. QSPR analysis was performed in order to identify molecular descriptors with the highest influence on %T and -logPapp and to create models which could be used for the design of novel HAA with improved gastrointestinal absorption. Obtained results indicate that introduction of branched side chain, as well as introduction of substituents on one phenyl ring (which disturb symmetry of the molecule) could have positive impact on gastrointestinal absorption. On the basis of these results, six novel HAA were designed and PAMPA parameters %T and -logPapp were predicted by use of selected QSPR models. Designed derivatives should have better gastrointestinal absorption than HAA tested in this study.

Oxidative stress induced by chlorpromazine in patients treated and acutely poisoned with the drug.

Background/Aim: Although chlorpromazine (CPZ) is an antipsychotic drug widely used in clinical practice for a long time, its mechanism of action has not been entirely defined. An extremely difficult managing of patients acutely poisoned with CPZ is additional reason for detailed studying its toxicity mechanisms. In this clinical study, we investigated whether the oxidative stress (OS) mediates CPZ toxic effects in the exposed patients. Methods: The patients were organized into 3 groups: the T-group - hospitalized patients receiving therapeutic doses of 75-150 mg CPZ/day; the overdosed group, divided into two subgroups: the group M and the group S - mildly (CPZ serum concentration: 0.21 ± 0.05 mg/L) and severely (CPZ serum concentration: 2.66 ± 0.25 mg/L) poisoned patients, respectively, and the group C (control group of healthy volunteers). Oxidative stress parameters [total antioxidative status (TAS) and malondialdehyde (MDA) in plasma)] and superoxide dismutase (SOD) activity in erythrocytes were measured spectrophotometrically, and CPZ concentrations in serum were monitored chromatographically. One set of measurements was performed in the group C and T, whereas two sets of measurements (after 24 hours and 48 hours) were done in the poisoned patients, groups M and S. Results: A decrease of TAS and increase of SOD activity were obtained in both subgroups of the poisoned patients, compared to the controls and the group receiving therapeutic doses of CPZ. A significant increase of MDA was achieved in severely poisoned patients, compared to all other groups. Conclusion: Changed oxidative stress parameters in patients poisoned with chlorpromazine indicate involvement of oxidative stress in the toxicity mechanism(s) of chlorpromazine.

Docking Studies, Synthesis and Biological Evaluation of ß-aryl-ß-hydroxy Propanoic Acids for Anti-inflammatory Activity.

BACKGROUND: Nonsteriodal anti-inflammatory drugs (NSAIDs) are numerous and widely used for more than 60 years, but there is still a strong need for developing novel selective NSAIDs. The need is justified by the fact that nonselective NSAIDs can produce serious gastric side effects and that some of the selective NSAID are withdrawn due to their cardiotoxic side effects. METHODS: Eight ß-hydroxy-ß-arylpropanoic acids, which belong to the arylpropanoic acid class of compounds, structurally similar to some nonsteroidal anti-inflammatory drugs (NSAIDs), were docked into 3D catalytic site of both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Seven out of those eight acids were synthesized using already published modification of Reformatsky reaction additionally optimized by increasing temperature. Synthesized compounds were tested in vivo in order to elucidate anti-inflammatory activity, gastric tolerability and impact on liver function of rats. RESULTS: Results of docking studies have indicated that all compounds have potential to selectively inhibit COX-2 isoform, but that the compounds containing polar substituents on phenyl ring are better inhibitors. Results of carrageenan-induced rat paw oedema test have shown that all compounds exhibit dose dependence and good gastric tolerability and none of the tested compounds have shown negative effect on liver function compared to ibuprofen. CONCLUSION: The compound containing polar nitro group in para position has shown the best docking results, anti-inflammatory activity, low hepatotoxicity and good gastric tolerability.

In vitro assessment of antiproliferative action selectivity of dietary isothiocyanates for tumor versus normal human cells.

Background/Aim: Numerous epidemiological studies have shown beneficial effects of cruciferous vegetables consumption in cancer chemoprevention. Biologically active compounds of different Brassicaceae species with antitumor potential are isothiocyanates, present in the form of their precursors - glucosinolates. The aim of this study was to determine the selectivity of antiproliferative action of dietary isothiocyanates for malignant versus normal cells. Methods: Antiproliferative activity of three isothiocyanates abundant in human diet: sulforaphane, benzyl isothiocyanate (BITC) and phenylethyl isothiocyanate, on human cervix carcinoma cell line - HeLa, melanoma cell line - Fem-x, and colon cancer cell line - LS 174, and on peripheral blood mononuclear cells (PBMC), with or without mitogen, were determined by MTT colorimetric assay 72 h after their continuous action. Results: All investigated isothiocyanates inhibited the proliferation of HeLa, Fem-x and LS 174 cells. On all cell lines treated, BITC was the most potent inhibitor of cell proliferation with half-maximum inhibitory concentration (IC50) values of 5.04 mmoL m-3 on HeLa cells, 2.76 mmol m-3 on Fem-x, and 14.30 mmol m-3 on LS 174 cells. Antiproliferative effects on human PBMC were with higher IC50 than on malignant cells. Indexes of selectivity, calculated as a ratio between IC50 values obtained on PBMC and malignant cells, were between 1.12 and 16.57, with the highest values obtained for the action of BITC on melanoma Fem-x cells. Conclusion: Based on its antiproliferative effects on malignant cells, as well as the selectivity of the action to malignant vs normal cells, benzyl isothiocyanate can be considered as a promising candidate in cancer chemoprevention. In general, the safety of investigated compounds, in addition to their antitumor potential, should be considered as an important criterion in cancer chemoprevention. Screening of selectivity is a plausible approach to the evaluation of safety of both natural isothiocyanates and synthesised analogues of these bioactive compounds.

Docking Studies and α-Substitution Effects on the Anti-Inflammatory Activity of ß-Hydroxy-ß-arylpropanoic Acids.

Six ß-hydroxy-ß-aryl propanoic acids were synthesised using a modification of Reformatsky reaction which has already been reported. These acids belong to the aryl propanoic acid class of compounds, structurally similar to the NSAIDs, such as ibuprofen, and an anti-inflammatory activity is thus expected. The aim of this work was to determine anti-inflammatory activity, examine gastric tolerability, and to carry out molecular docking experiments to identify potential COX-2 inhibitors among the ß-hydroxy-ß-aryl propanoic acids, and to elucidate the effect α-methyl substitution on the anti-inflammatory activity. Anti-inflammatory activity and gastric tolerability were determined on rats using carrageenan induced paw oedema method, and docking studies were carried out using Autodock v4.0.1. The range of ED50 values is between 127 µmol/kg and 15 µmol/kg, while the result for ibuprofen is 51.7 µmol/kg. Only slight hyperaemia or few petechiae were spotted on rat's stomach. The results indicate that all compounds possess significant anti-inflammatory activity after oral administration, and that 2-methyl-3-hydroxy-3,3-diphenyl-propanoic acid has greatest activity, surpassing that of ibuprofen, a standard NSAID. Another compound, 3-hydroxy-3,3-diphenylpropanoic acid, shows activity matching that of ibuprofen, and is non-chiral and is proven to be non-toxic. The most of investigated compounds have interactions with P3 anchor site like COX-2 selective inhibitors. No tested substances or ibuprofen produced any significant gastric lesions.

Docking studies and anti-inflammatory activity of beta-hydroxy-beta-arylpropanoic acids.

The article describes a two-step synthesis of diastereomeric 3-hydroxy-2-methyl-3-(4-biphenylyl)butanoic acids. In the first step an intermediate alpha-bromo propanoic acid 1-ethoxyethyl ester was synthesized. The second step is a new modified Reformatsky reaction in presence of Zn in tetrahydrofuran (THF) at -5 to 10 degrees C between the previously synthesized intermediate and 4-acetylbiphenyl. Synthesis of the other studied beta-hydroxy-beta-arylpropanoic acids has already been reported. These beta-hydroxy-beta-arylpropanoic acids belong to the arylpropanoic acid class of compounds, structurally similar to the NSAIDs such as ibuprofen. The anti-inflammatory activity and gastric tolerability of the synthesized compounds were evaluated. Molecular docking experiments were carried out to identify potential COX-2 inhibitors among the beta-hydroxy-beta-aryl-alkanoic acids class. The results indicate that all compounds possess significant anti-inflammatory activity after oral administration and that the compounds 2-(9-(9-hydroxy-fluorenyl))-2-methylpropanoic acid (5) and 3-hydroxy-3,3-diphenyl-propanoic acid (3) possess the strongest anti-inflammatory activity, comparable to that of ibuprofen, a standard NSAID,and that none of tested substances or ibuprofen produced any significant gastric lesions.