Effects of 13 T Static Magnetic Fields (SMF) in the Cell Cycle Distribution and Cell Viability in Immortalized Hamster Cells and Human Primary Fibroblasts Cells

Magnetic resonance image （MRI） systems with a much higher magnetic flux density were developed and applied for potential use in medical diagnostic. Recently, much attention has been paid to the biological effects of static, strong magnetic fields （SMF）. With the 13 T SMF facility in the Institute of Plasma Physics, Chinese Academy of Sciences, the present study focused on the cellular effects of the SMF with 13 T on the cell viability and the cell cycle distribution in immortalized hamster cells, such as human-hamster hybrid （AL） cells, Chinese hamster ovary （CHO） cells, DNA double-strand break repair deficient mutant （XRS-5） cells, and human primary skin fibroblasts （AG1522） cells. It was found that the exposure of 13 T SMF had less effect on the colony formation in either nonsynchronized or synchronized AL cells. Moreover, as compared to non-exposed groups, there were slight differences in the cell cycle distribution no matter in either synchronized or nonsynchronized immortalized hamster ceils after exposure to 13 T SMF. However, it should be noted that the percentage of exposed AG1522 cells at G0/G1 phase was decreased by 10% as compared to the controls. Our data indicated that although 13 T SMF had minimal effects in immortalized hamster cells, the cell cycle distribution was slightly modified by SMF in human primary fibroblasts.

Protective Effect of Space Ginseng Yeast on Human Primary Fibroblasts under Simulated Microgravity Condition

[Objectives] To study the protective effect of Space Ginseng Yeast on human primary fibroblasts. [Methods] Multiple indicators were used to simulate the microgravity effect,so as to study the protective effect of Space Ginseng Yeast on human primary fibroblasts under simulated microgravity condition. [Results]Space Ginseng Yeast could improve changes of cell morphology and decline of the survival rate caused by microgravity,restore the expression and effective arrangement of cytoskeletal protein Tubulin,extracellular matrix proteins Integrin and Fibronectin,and can inhibit the abnormal expression of MMP-1. The protective effect of Space Ginseng Yeast diluted 20-500 times is better,and the protective effect of Space Ginseng Yeast diluted 100 times is the most obvious. [Conclusions] Space Ginseng Yeast can protect damage of human primary fibroblasts caused by simulated microgravity.

Synergistic antitumor effects of in vivo production of human endostatin and tissue inhibitor of metalloproteinase-1 in mice after subcutaneous implantation of primary fibroblasts transfected by adenovirus-mediated gene delivery

Background Tissue inhibitor of metalloproteinase （TIMP）-1 is a multifunctional protein. The aim of the study was to examine the feasibility of using a combination of adenovirus-mediated gene delivery of TIMP-1 plus endostatin and cell transplantation techniques to treat tumor growth and metastasis in mouse melanoma.Methods A enzyme-linked immunosorbent assay （ELISA） was used to detect the level of TIMP-1 and endostatin in vitro and in vivo. A tumor bearing mouse model and an experimental lung metastasis model in animal experiments were used to explore the therapeutic effect of in vivo production of human TIMP-1 and endostatin after the implantation of primary fibroblasts infected with the indicated adenovirus into tumor-bearing mice and a cytochemical method was used to observe histopathological changes of the tumor. An experimental lung metastasis model was established by injecting B16BL6 cells into the tail vein of mice and adenovirus-infected primary fibroblasts were subcutaneously implanted into the mice 24 hours later. Twenty-one days after tumor cell injection, mice were sacrificed to examine the effect on nodules visible as black forms on the surface of the lungs in B16BL6 cells.Results TIMP-1 and endostatin were secreted into the supernatants of cultures of Ad-TIMP-1 and Ad-End-infected mouse primary fibroblasts. We also observed that implantation of fibroblasts infected with Ad-TIMP-1 alone, Ad-End alone, or Ad-TIMP-1 plus Ad-End resulted in detectable blood levels which may clearly inhibit the tumor growth and metastasis in a murine melanoma model.Conclusion These results suggest the high capacity of transfection for the delivery of TIMP-1 or endostatin gene constructs into primary fibroblasts, and demonstrate that the implantation of TIMP-1 and endostatin producing fibroblasts at a site in vivo where direct secretion of TIMP-1 and endostatin into the blood is possible represented a promising approach for the development of cancer therapy.

Cytotoxicity of Modified Nonequilibrium Plasma with Chlorhexidine Digluconate on Primary Cultured Human Gingival Fibroblasts

The aim of this study was to investigate the cytotoxicity of modified nonequilibrium plasma with chlorhexidine digluconate（CHX） on human gingival fibroblasts（HGFs）, and to evaluate the biosecurity of modified nonequilibrium plasma with 2% CHX as a new method of root canal treatment. Tissue samples taken from human gingiva were primarily cultured and passaged. Cells from passages 3–7 were used. HGFs were treated by modified nonequilibrium plasma with 2% CHX for 0 min（control group）, 30 s, 1 min, 1.5 min, 3 min, 5 min, and 10 min, respectively, and then they were incubated for 0, 24, and 48 h. After that, cell counting kit-8（CCK-8） assay was applied to analyze the cytotoxicity of modified nonequilibrium plasma with 2% CHX on HGFs. There was no significant difference between the 0 h group treated with the modified nonequilibrium plasma for 1 min and the control group（P〉0.05）. However, there were significant differences between all the other treated groups and the control group（P〈0.05）. When treated for 1.5 min or shorter, the cell viability was obviously increased; while treated for 3 min or longer, it was obviously reduced. Moreover, when successively cultured for 0, 24, and 48 h, cell viability was decreased at first and then increased in the 3-min-treated and 5-min-treated groups. The modified nonequilibrium plasma with 2% CHX was of no influence on cell viability in 1.5 min treatment, and it could be safely used on root canal treatment.