Impacts of maternal separation stress on ethanol-related responses, anxiety- and depressive-like behaviors in adolescent mice.

The present work evaluated the consequences of chronic maternal separation (MS), an animal model of early-life stress, on ethanol intake and striatal Fos expression induced by ethanol consumption. Furthermore, we analyzed MS impacts on anxiety- and depressive-like behaviors and on locomotor and plasma corticosterone responses to intraperitoneal treatment with ethanol in adolescent mice. For that, male and female C57BL/6J mice were exposed or not to MS stress, for 3 h per day, from postnatal day (PND) 1 to 14, and submitted to behavioral tests from PND 28. In Experiment 1, MS and control groups of mice were submitted to an involuntary ethanol intake protocol, and striatal Fos expression following ethanol exposure was analyzed. In Experiment 2, mice behavior was assessed in elevated plus-maze, sucrose splash, saccharin preference, and open field tests. Locomotor and plasma corticosterone responses induced by a systemic dose of ethanol (1.75 g/kg) were also evaluated. Our results demonstrated that MS increased ethanol intake only in an acute manner and did not impact ethanol-induced Fos expression in the dorsal striatum and nucleus accumbens (NAc) core and shell subregions. MS did not change the parameters analyzed during elevated plus-maze, sucrose splash, preference for saccharin, and open field tests. MS did not affect locomotor activity following ethanol injection nor plasma corticosterone response to the drug. Thus, our data showed that MS transiently increased ethanol intake. However, early-life stress did not impact Fos, locomotor, or plasma corticosterone responses to the drug. In addition, MS did not affect anxiety- and depressive-like behaviors in adolescent mice.

Identification of a tyrosine kinase-phosphorylated protein in arachidonic acid- and prostaglandin A(2)-treated cells in vitro.

The effects of 20 microg/ml exogenous arachidonic acid (AA) and prostaglandin A(2) (PGA(2)) were evaluated on total tyrosine kinase (TK) activity and tyrosine phosphorylation status in HeLa and MCF-7 cells. AA and PGA(2) increased TK activity in both HeLa and MCF-7 cells. Western blotting employing an anti-phosphotyrosine antibody showed only one protein of approximately 55 kDa (approximately 55 kDa) to be phosphorylated in the MCF-7 cells, while a variety of proteins were phosphorylated in the HeLa cells, including the approximately 55 kDa protein. Amino acid analyses as well as Matrix Assisted Laser Desorption Ionization were conducted on this protein from different cell lines and it was shown to be similar. Comparison to p53 did not show similarities. The identity of this protein needs to be further characterized to help elucidate the signal transduction pathways of AA and PGA(2).

The effects of chelidonine on tubulin polymerisation, cell cycle progression and selected signal transmission pathways.

Chelidonine is a tertiary benzophenanthridine alkaloid known to cause mitotic arrest and to interact weakly with tubulin. Our interest in chelidonine began when we found it to be a major contaminant of Ukrain, which is a compound reported to be selectively toxic to malignant cells. The effects of chelidonine in two normal (monkey kidney and Hs27), two transformed (Vero and Graham 293) and two malignant (WHCO5 and HeLa) cell lines, were examined. Chelidonine proved to be a weak inhibitor of cell growth, but no evidence for selective cytotoxicity was found in this study. It was confirmed that chelidonine inhibits tubulin polymerisation (IC50 = 24 microM), explaining its ability to disrupt microtubular structure in cells. A G2/M arrest results, which is characterised by abnormal metaphase morphology, increased levels of cyclin B1 and enhanced cdc2 kinase activity. Exposure of all cell lines examined to chelidonine leads to activation of the stress-activated protein kinase/jun kinase pathway (SAPK/JNK).

Ukrain(TM), a semisynthetic Chelidonium majus alkaloid derivative, acts by inhibition of tubulin polymerization in normal and malignant cell lines.

Ukrain(TM) has been described as a semisynthetic Chelidonium majus alkaloid derivative, which exhibits selective toxicity towards malignant cells only. Its mechanism of action has hitherto been uncertain. We found that Ukrain(TM) inhibits tubulin polymerization, leading to impaired microtubule dynamics. This results in activation of the spindle checkpoint and thus a metaphase block. The effects of Ukrain(TM) on the growth, cell cycle progression and morphology of two normal, two transformed and two malignant cell lines did not differ. We could thus find no evidence for the selective cytotoxicity previously reported for Ukrain(TM).

The antimitotic effects of Ukrain, a Chelidonium majus alkaloid derivative, are reversible in vitro.

Ukrain is alleged to be an effective chemotherapeutic drug which causes minimal side-effects as a result of selective toxicity towards malignant cells only. We previously failed to confirm this claim and found Ukrain to be equally toxic to normal, transformed and malignant cell lines by causing a metaphase arrest. In this study we have found the antimitotic actions of Ukrain to be reversible in low doses in vitro, as shown by flow cytometry and concurrent haematoxylin and eosin stains. We hypothesize that the lack of side-effects found in vivo may be due to the lack of therapeutically effective dosages being administered, therefore enabling cells to overcome the metaphase arrest and survive.

Comparative study of the effects of polyunsaturated fatty acids and their metabolites on cell growth and tyrosine kinase activity in oesophageal carcinoma cells.

The effects of exogenous gamma-linolenic acid (GLA), arachidonic acid (AA), prostaglandin E2 (PGE2) and prostaglandin A2 (PGA2) were evaluated on cell growth in two squamous oesophageal carcinoma cell lines, WHCO1 and WHCO3 and normal monkey kidney (NMK) cells. In both cancer cell lines all four compounds inhibited cell growth significantly. Indomethacin (I) alone, or in combination with either GLA or AA, caused marked inhibition of cell growth in WHCO3. Total tyrosine kinase (TK) activity was determined after exposure of all three cell types to the lipid compounds. Negligible differences were observed in TK activity between treated and untreated NMK cells. Small increases were noticed in WHCO1. Marked TK stimulation was observed in WHCO3. Addition of indomethacin to WHCO3 also increased TK activity above control value. Tyrosine phosphorylation status of exposed cells indicated that a band of approximately 55 kDa (approximately 55 kDa) was primarily influenced in both WHCO3 and WHCO1. PGA2 caused a decrease in tyrosine phosphorylation of the approximately 55 kDa protein in all three cell types. Negligible differences were observed in the tyrosine phosphorylation status of the approximately 55 kDa in NMK cells exposed to GLA, AA and PGE2 respectively. However, tyrosine phosphorylation of a number of other proteins (21.5-97.4 kDa) was observed in NMK cells. Flow cytometry studies showed an increase in S phase and decrease in G1 phase in WHCO3 exposed to PGE2 and PGA2. Indomethacin alone, or in combination with GLA and AA, respectively, lead to an increase in G1 and a decrease in S phase. Induction of p53 levels was observed in WHCO3 cells exposed to GLA, AA, PGA2, indomethacin and the combination of indomethacin and GLA or AA.

The relative buffering power of cardioplegic solutions.

Those factors that prolong myocardial tolerance to global ischemia constitute an important prerequisite for effective cardioplegia. This study contrasts the relative buffering power of bicarbonate-based and tromethamine-based hyperkalemic crystalloid cardioplegic solution with histidine protein-type buffer (Bretschneider) solution. In addition, the solutions were compared with titration of whole blood and myocardial muscle homogenate.