OBJECTIVETo observe the ability of triple helix-forming oligonucleotides (TFOs) modified with manganese porphyrin to combine with and cleave HBV DNA fractions.

METHODSTFO were modified with manganese porphyrin and acridines, and then reacted with the (32)P labeled HBV DNA fragments at 37 degrees C in vitro (pH 7.4). Electrophoretic mobility shift assays and DNase I footprinting tests were used to show the affinity and specificity of TFO to bind to target sequences. The ability of TFO to cleave HBV DNA fragments was tested by cleavage experiments.

RESULTSTFO modified with manganese porphyrin and acridine could bind to the target sequence in a sequence-dependent manner, with a Kd value of 3.5 x 10(-7) mol/L and a relative affinity of 0.008. In the presence of potassium monopersulfate (KHSO(5)), TFO modified with manganese porphyrin and acridine could cleave the target sequence where the triplex DNA was formed.

CONCLUSIONIn the presence of KHSO(5), TFO modified with manganese porphyrin and acridine could bind and cleave the target HBV-DNA in a sequence-dependent manner.

DNA ; drug effects ; pharmacology ; DNA, Viral ; chemistry ; drug effects ; Hepatitis B virus ; genetics ; Manganese ; pharmacology ; Metalloporphyrins ; pharmacology ; Potassium Compounds ; pharmacology ; Sulfates ; pharmacology

OBJECTIVETo investigate the effect of the photodynamic therapy (PDT) with the new water-soluble metalloporphyrin compound on human prostate cancer PC-3 cells in vitro and the anticancer mechanism of PDT.

METHODSThe new water-soluble manganese, 5,10,15, 20-tetra (N-methyl4-pyridyl) porphinato (2-) tetraiodide salt, was synthesized. The PC-3 cells were treated with the compound of serial concentrations(0, 0.1, 1, 1.0 micromol/L) followed by irradiation of different dosages of visible light. The techniques of MTT and Annexin-V/propidium iodide double-labeled flow cytometry (FCM) were applied to measuring the inhibitory effect of the compound on the growth activity and apoptosis of the cells.

RESULTSWhen the metalloporphyrin compound concentration was within 10 micromol/L and the irradiation time was within 30 min, the water-soluble metalloporphyrin compound had a significant inhibitory effect on the proliferation of PC-3 cells and induced PC-3 cell apoptosis, and the effects depended greatly on metalloporphyrin concentration and illumination dosages. Higher concentrations and dosages induced the death of the majority of PC-3 cells.

CONCLUSIONThe PDT of the water-soluble metalloporphyrin compound followed by light irradiation has a distinctive killing effect on PC-3 cells in vitro, and the rates of proliferation inhibition and cell apoptosis are correlated with metalloporphyrin concentration and the dosages of light irradiation. The results suggest that the mechanism of metalloporphyrin PDT may be involved with the induction of apoptosis in human prostate cancer cells.

Apoptosis ; drug effects ; radiation effects ; Cell Line, Tumor ; Dose-Response Relationship, Drug ; Dose-Response Relationship, Radiation ; Humans ; Male ; Metalloporphyrins ; pharmacology ; Photochemotherapy ; Prostatic Neoplasms ; pathology

AIMTo synthesize four water-soluble metal porphyrins [5, 10, 15, 20-tetra[4-(4'-pyridine-1) butyloxy phenyl] metalloporphyrins bromide, metal = Zn (I), Cu (II), Mn (III) and Co (IV)] as analogous enzyme having two anti-active oxygen functions.

METHODSThe first function, scavenging O2-, has been proved by using riboflavine-methionine photoreduction methods. The second function, scavenging H2O2, has been demonstrated by using the oxidating Vit C. The third function, scavenging HO*, has been demonstrated by using Fenton reaction. The complexes were measured by the mice liver homogenate technique of mice.

RESULTSFour model compounds could scavenge O2- in the concentration range of 1.0 x 10(-5) - 1.0 x 10(-6) mol x L(-1), decompose H2O2 in the concentration of 1.5 x 10(-6) - 1.0 x 10(-6) mol x L(-1), scavenge HO* in the concentration of 2.0 x 10(-8) - 1.0 x 10(-8) mol x L(-1). All showed that they had obvious action of decreasing the lipid peroxidation in the concentration of 1.0 x 10(-7) mol x L(-1).

CONCLUSIONAll above-mentioned complexes were considered to be qualified analogous enzymes of anti-active oxygen.

Animals ; Cobalt ; Copper ; Free Radical Scavengers ; chemical synthesis ; pharmacology ; Hydrogen Peroxide ; metabolism ; Hydroxyl Radical ; metabolism ; In Vitro Techniques ; Lipid Peroxidation ; drug effects ; Liver ; metabolism ; Malondialdehyde ; metabolism ; Manganese ; Metalloporphyrins ; chemical synthesis ; pharmacology ; Mice ; Reactive Oxygen Species ; metabolism ; Zinc

In vascular smooth muscle cells (VSMCs), induction of the heme oxygenase-1 (HO-1) confers vascular protection against cellular proliferation mainly via its up-regulation of the cyclin-dependent kinase inhibitor p21(WAF1/CIP1) that is involved in negative regulation of cellular proliferation. In the present study, we investigated whether the phytochemical curcumin and its metabolite tetrahydrocurcumin could induce HO-1 expression and growth inhibition in rat VSMCs and, if so, whether their antiproliferative effect could be mediated via HO-1 expression. At non-toxic concentrations, curcumin possessing two Michael-reaction acceptors induced HO-1 expression by activating antioxidant response element (ARE) through translocation of the nuclear transcription factor E2-related factor-2 (Nrf2) into the nucleus and also inhibited VSMC growth triggered by 5% FBS in a dose-dependent manner. In contrast, tetrahydrocurcumin lacking Michael-reaction acceptor showed no effect on HO-1 expression, ARE activation and VSMC growth inhibition. The antiproliferative effect of curcumin in VSMCs was accompanied by the increased expression of p21(WAF1/CIP1). Inhibition of VSMC growth and expression of p21(WAF1/CIP1) by curcumin were partially, but not completely, abolished when the cells were co- incubated with the HO inhibitor tin protoporphyrin. In human aortic smooth muscle cells (HASMCs), curcumin also inhibited growth triggered by TNF-alpha and increased p21(WAF1/CIP1) expression via HO-1-dependent manner. Our findings suggest that curcumin has an ability to induce HO-1 expression, presumably through Nrf2-dependent ARE activation, in rat VSMCs and HASMCs, and provide evidence that the antiproliferative effect of curcumin is considerably linked to its ability to induce HO-1 expression.
Active Transport, Cell Nucleus ; Animals ; Aorta/cytology ; Cell Nucleus/metabolism ; Cell Proliferation/*drug effects ; Cells, Cultured ; Curcumin/analogs & derivatives/*pharmacology ; Cyclin-Dependent Kinase Inhibitor p21/biosynthesis/metabolism ; Gene Expression Regulation ; Heme Oxygenase (Decyclizing)/biosynthesis/genetics/*physiology ; Heme Oxygenase-1/biosynthesis/genetics/*physiology ; Humans ; Metalloporphyrins/pharmacology ; Muscle, Smooth, Vascular/drug effects/*physiology ; Myocytes, Smooth Muscle/drug effects/*physiology ; NF-E2-Related Factor 2/metabolism ; Protoporphyrins/pharmacology ; Rats ; Regulatory Sequences, Nucleic Acid ; Response Elements ; Tumor Necrosis Factor-alpha/pharmacology