Cytotoxic effects of cyclophosphamide (CPA), paclitaxel (PCT), and docetaxel (DTX) and their modulation by cytochrome P450 (CYP) metabolism were studied by incubating cell lines L929 and P388D1 with or without rat liver microsomes. The microsomes themselves were not cytotoxic. P388D1 cells were more sensitive to CPA, PCT, and DTX than L929 cells. CYP2B1-, CYP3A-, and CYP2E1-induced microsomes effectively oxidized the prodrug CPA to cytotoxic products in 2-h incubation periods. Cytotoxicity of DTX and PCT for P388D1 cells became apparent 24 h after a 2-h incubation period with the drugs, and their effects were enhanced by CYP2E1 microsomes, but markedly decreased by CYP3A-induced microsomes. DTX and PCT without microsomes caused a dose-related cytotoxicity in P388D1 and HeLa cells. P388D1 and HeLa cells did not grow after a 24-h exposure to 1-10 microM DTX, but about 0.1% of cells survived exposure to 1-10 microM PCT. After 4 weeks of multiplication, the surviving P388D1 cells displayed lower sensitivity to DTX and PCT, but cytotoxicity in HeLa cells was unchanged and their growth ability decreased. In P388D1 cells, PCT with DTX (0.1, 0.5. 1, 2.5, or 5 microM) showed only additive cytotoxicity, although they reportedly act in different phases of the cell cycle. In P388D1 cells treated with DTX or PCT, normal mononuclear cells disappeared and the cell diameter increased up to threefold. Mulberry-like nuclei developed, giving rise to multiple nuclei, which were hyper- or hypochromatic. Chromatin condensation in some multiple nuclei and cell shrinkage of some cells fit the definition of apoptosis, but enlargement of the surviving cells and numerous hypochromatic nuclei do not. In conclusion, L929 and P388D1 cells incubated with microsomes enabled the role of various CYP enzymes in the effect of anticancer drugs to be assessed. The delayed cytotoxicity of DTX and PCT compared to that of CPA was related to their different mode of action. Fluorescent microscopy revealed quantitatively different effects of PCT and DTX on the nuclei, indicating that their mode of action may not be completely identical.
Background/Aims: In addition to their lipid-lowering effects, HMG-CoA reductase inhibitors (statins) induce a variety of pleiotropic actions that have been recently studied in the area of cardiovascular and renal protection. In the present studies we sought to determine whether statins retain beneficial effects in the experimental model of NO deficiency achieved by chronic administration of a pressor dose of L-arginine analogue N-nitro-L-arginine-methyl ester (L-NAME). Methods: To address this issue, blood pressure (BP), renal function (GFR), and albuminuria were determined in rats treated for 4 weeks with L-NAME, L-NAME + atorvastatin (ATO), and in untreated controls. In addition, renal cortical protein expression of caveolin 1 (CAV1), vascular endothelial growth factor (VEGF), and activity of RhoA were also determined. Results:L-NAME administration resulted in sustained elevation of BP, decreased GFR, and in higher albuminuria as compared to control animals. Co-administration of ATO with L-NAME normalized albuminuria and prevented decreases in GFR in L-NAME rats without having an impact on pressor effects of L-NAME. CAV1 protein expression was similar in all groups of rats. In contrast, VEGF expression and RhoA activity was increased in L-NAME-treated animals, and normalized with co-administration of ATO. Conclusion: Treatment with ATO exerts early nephroprotective effects in the NO-deficient model of hypertension. These effects could be mediated by amelioration of VEGF expression and reduction of RhoA activity.
Benzene (B), toluene (T), ethylbenzene (EB), styrene (S) and xylene isomers (oX, mX, pX) are important environmental pollutants and B is a proved human carcinogen. Their inhalation by male Wistar rats (4 mg/l, 20 h/day, 4 days) caused cytochrome P450 (P450) induction. The degree of P450 2B1 induction increased and that of 2E1 decreased in the series B, T, EB, S, oX, mX and pX, as estimated by Western blots, while neither solvent was as effective for 2B1 induction as phenobarbital and B was more effective for 2E1 than ethanol. The levels of several other P450s decreased after exposure to these solvents, B being most effective. Exposure to these solvents increased in vitro hepatic microsomal oxidation of B and aniline (AN) (2E1 substrates) 3 to 6-fold, indicating induction of this P450. T oxidation was increased 2 to 4-fold and chlorobenzene (ClB) oxidation 3-fold. Sodium phenobarbital (PB, 80 mg/kg/day, 4 days, i.p.) did not increase ethylmorphine (EM) and benzphetamine (BZP) demethylation (2B1 substrates), neither of the B derivatives did so, and oX decreased it; however, pentoxyresorufin O-dealkylation was well related to the immunochemically detected 2B1 levels in control, PB and B microsomes. PB did not increase B, but increased T and ClB oxidation 2-4 and 3-fold, respectively, indicating possible 2B1 role in their oxidation. B oxidation after various inducers was related to immunochemical 2E1 levels, T and ClB oxidation to both 2B1 and 2E1 and AN oxidation to 2E1 and 1A2 levels.(ABSTRACT TRUNCATED AT 250 WORDS)
IntroductionThe time course of pregnancy-associated plasma protein-A (PAPP-A) levels was studied at admission, immediately after percutaneous coronary intervention (PCI) and 1, 2, 4, 6, 12, 24 and 48 h after PCI in acute coronary syndrome with ST segment elevation (ACS-STE) to determine the impact of PCI, concomitant clinical complications and heparin administration.Material and methodsPregnancy-associated plasma protein-A serum levels, examined by the KryptorTM system, were studied in 30 heparinized PCI ACS-STE patients, in 10 elective PCIs and 12 coronary angiographies with heparin, and in 5 patients with normal coronary angiogram without heparin.ResultsHeparin caused a high PAPP-A increase in ACS-STE patients, in all patients with heparin without ACS and angiographic signs of significant atherosclerosis. This increase was directly associated with heparin dosage and activated clotting time (ACT) (r = 0.71, p = 0.0001) and inversely with the interval between heparin applications and time of serum sampling. It was followed by a rapid decrease within 1 to 2 h and return to normal levels in 10 to 12 h. In ACS-STE patients the decrease was significantly slower than in heparinized elective PCI and angiography patients. The PAPP-A increase was not significantly dependent on the length of PCI. Persistent increase after 24 h was associated in 4/7 patients with concomitant clinical complications.ConclusionsThe diagnostic validity of PAPP-A can be verified only within the 1st h after clinical onset of ACS before heparin administration, the prognostic value in heparinized patients not earlier than 12 h after the last heparin application, if ACT is normal and serious clinical concomitant complications are eliminated.
Follicle-stimulating hormone receptors (FSHRs) are almost exclusively expressed on granulosa cells, and FSH action is probably most clearly reflected in intrafollicular hormone milieu of antral follicles. Little is known about the possible effects of the common single nucleotide polymorphism (SNP) FSHR −29G > A (rs1394205) on hormonal conditions in humsan small antral follicles (hSAFs) obtained from women in the natural menstrual cycle. This study investigated the follicle fluid (FF) concentrations of anti-Müllerian hormone, estradiol, progesterone, androstenedione, and testosterone in hSAF in relation to the different genotypes of FSHR −29G > A. FF from 362 follicles was collected in 95 women undergoing fertility preservation, who did not suffer from a disease that directly affected ovarian function. The testosterone levels of the minor A/A genotype were significantly increased compared to the A/G and the G/G genotype. Furthermore, significantly reduced androstenedione levels were observed for the G/G genotype, as compared to the A/G genotype, while the other hormones did not show statistical significant differences. In conclusion, the androgen levels of hSAF were significantly elevated in the minor SNP genotype in the FSHR promoter polymorphism FSHR −29G > A.
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