ABSTRACT
The antiproliferative effect of serotonin-reuptake inhibitors (SSRI) and serotonin antagonists has been demonstrated in prostate tumors. Since Hypericum perforatum components act as serotonin-reuptake inhibitors and exert cytotoxic effects on several human cancer cell lines, in this work we analyzed the effect of a treatment with Hypericum perforatum extract (HPE) on the growth of human prostate cancer cells in vitro and in vivo. This study highlighted a significant reduction of tumor growth and number of metastasis suggesting that this natural compound may be useful in the treatment of prostate cancer.
Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Hypericum/chemistry , Plant Extracts/therapeutic use , Prostatic Neoplasms/pathology , Prostatic Neoplasms/prevention & control , Animals , Cell Division/drug effects , Humans , Male , Methanol/metabolism , Mice , Mice, Nude , Prostatic Neoplasms/chemistry , Tumor Cells, Cultured/transplantationABSTRACT
Preprotachykinin-A (PPT-A) mRNA levels in discrete rat brain regions were examined. Analysis of silver grains revealed a 19.2% and 31.5% statistically significant decrease in PPT-A mRNA in the dorsal and ventral caudate putamen (d-CPu and v-CPu), respectively, a 30% lower expression of PPT-A mRNA in the bed nucleus of the stria terminalis (BNST), a 33.7% decrease in PPT-A mRNA in the habenula (Hb), and a 30% decrease of PPT-A mRNA levels in the posterodorsal part of the medial amygdala (MePD). Results show that aging of the CNS is associated with widespread changes in tachykinin gene expression, suggesting that alterations in the tachykinergic system may have implications in the physiopathology of the elderly.
Subject(s)
Aging/metabolism , Protein Precursors/metabolism , RNA, Messenger/metabolism , Tachykinins/metabolism , Animals , In Situ Hybridization , Male , RatsABSTRACT
The mechanisms by which vanadate exerts a toxic effect on living organisms are not completely understood. This is principally due to the variety of intracellular targets of the metal and to the changes in the chemical form and oxidation states that vanadate can undergo, both in the external environment and intracellularly. In order to further elucidate the reasons for vanadate toxicity, and assuming that common detoxification mechanisms can be evoked by a general heavy metal response, we have compared some aspects of the cellular responses to vanadate and copper in the yeast Hansenula polymorpha. By means of 2D electrophoresis we show the existence of common determinants in the responses to vanadate- and copper-induced stresses. Moreover, we demonstrate that both metals induce significant increases in antioxidant enzyme levels, and that there are significant overlaps in the heavy metal and oxidative stress responses. Interestingly, vanadate induces an increase in catalase activity that is much higher than that seen with copper and, unlike copper, does not cause lipid peroxidation of cellular membranes. This suggests that H. polymorpha cells activate a further specific detoxification pathway against vanadate-induced oxidative insults.
Subject(s)
Copper/pharmacology , Pichia/drug effects , Vanadates/pharmacology , Catalase/metabolism , Electrophoresis, Gel, Two-Dimensional , Enzyme Activation/drug effects , Fungal Proteins/metabolism , Oxidative Stress , Pichia/physiology , Superoxide Dismutase/metabolism , Thiobarbituric Acid Reactive Substances/analysisABSTRACT
A Bacillus stearothermophilus in vitro translational system has been developed to study the expression of the three cistrons (infC, rpml, and rplT) constituting the infC operon of this bacterium. When directed by homologous in vitro transcribed infC tricistronic mRNA, this system, which consists of partially purified and purified components of the B. stearothermophilus translational apparatus, synthesizes with high efficiency and specificity the three gene products (IF3, L35, and L20) in a ratio similar to that found in vivo (i.e., about 1:6:6). The three cistrons are translationally coupled and expressed in a specific temporal order: a low level of IF3 synthesis stimulates the expression of L35 which, in turn, greatly stimulates the synthesis of L20 and IF3. Protein L20 and an excess of IF3 were found to act as translational feedback inhibitors of the entire operon. The synthesis of IF3 displayed a strong dependence on IF2. This dependence as well as the repressibility by excess IF3 were found to be due to the presence of the rare AUU initiation triplet at the beginning of infC.
