ABSTRACT
Objective To estimate any influence of strong pulsed magnetic fields on the expression of growth-related genes in human bladder cancer BIU-87 cells. Methods Human BIU-87 cells were cultured in vitro and randomly divided into a magnetic field group and a control group. Each group was further divided into 24 h, 48 h and 72 h sub-groups. The magnetic field group cells were exposed to an 8 T magnetic field pulsed at 15 Hz for 2 h every day. The control group cells also placed on the same environment, but not exposed to any strong, pulsed magnetic field. The expression of B cell lymphoma/leukemia gene-2 (Bcl-2) mRNA, Bax mRNA and caspase-3 mRNA was measured with RT-PCR, and flow cytometry was used to evaluate the expression of the Bcl-2, Bax and caspase-3 genes of the tumor cells in vitro. Results The expression of Bax mRNA and protein was significantly higher in the cells exposed to the magnetic field than in the control groups. The expression of Bcl-2 mRNA and protein was significantly less. The expression of caspase-3 mRNA and protein in the two groups showed no significant differences.Conclusions A strong, pulsed magnetic field can inhibit the growth of bladder tumor BIU-87 cells and promote their apoptosis. The mechanism is probably related with the magnetic field promoting Bax mRNA and protein expression and inhibiting Bcl-2 mRNA and protein expression.
ABSTRACT
Objective To study the effect of magnetic stimulation on the expression of B cell lymphoma/leukemia gene 2 ( Bcl-2 ) and caspase-3 genes, and the apoptosis of neurons in rats with spinal cord injury (SCI).Methods Sixty rats were randomly divided into a magnetic stimulation group, a model group and a sham-operation group. An SCI model was established in the magnetic stimulation and model groups. The magnetic stimulation was applied at the 6th, 12th, 24th and 72nd hour after the operation to the rats in the magnetic stimulation group, and sham magnetic stimulation was given to the model group and sham-operation group rats at the same time points. Two hours after treatment, 5 rats of each group were sacrificed and their injured spinal cords were sectioned. The gene expressions were detected using immunohistochemical techniques, and apoptosis of neurons was observed by the TUNEL method. Results Few apoptotic cells were found in the sham-operation group, but more were found in the model group. Apoptotic cells in the magnetic stimulation group were significantly fewer than in the model group. The expression of both Bcl-2 and caspase-3 in the magnetic stimulation and model groups was significantly higher than in the sham-operation group at the different time points. Expression of Bcl-2 in the magnetic stimulation group was significantly higher than in the model group, but expression of caspase-3 in the magnetic stimulation group was significantly lower than in the model group. Conclusions Magnetic stimulation up-regulates the expression of Bcl-2 genes and down-regulates the expression of caspase-3 in injured neurons. Magnetic stimulation might have protective and rehabilitative effects after human SCI.