Effects Of Low Power Microwave Radiation On Cultured Rabbit Lens, Lens Epithelial Cells And Related Gene Expression

Increased applications of electromagnetic fields are of great concern to public health. The character of the natural electromagnetic field has been altered significantly due to technological progress and numerous man-made sources such as industry, traffic, medicine, radio, television, microwaves, RTV apparatuses etc. These sources of non-ionizing radiation cause atmospheric pollution similar to the pollution from various industrial sources.The lens of the eye is derived from ectoderm and grows throughout life. This transparent organ consists of a single, cuboidal layer of epithelial cells on the anterior surface and elongated, terminally differentiated epithelial cells, or fiber cells, in the interior. The lens epithelial layer is critical for lens physiology, and insults to this layer can play a role in lens pathology. Many studies have found that damage to the epithelium can be an early event in cataractogenesis. However, no systematic studies have investigated the biological effects of low power microwave radiation on lens epithelial cells.It is well recognized that microwaves affect the biological functions of living organisms at both the cellular and molecular levels and can lead to the appearance of genotoxic effects. However, the mechanisms by which electromagnetic fields exert their biological effects remain poorly characterized. Special attention has been given toinvestigating the effects of low power microwave radiation (<10 mW/cm2) on cell growth, cell cycle progression and DNA synthesis. In human lymphocytes, 450MHz Fields at around 1.0mW/cm2 affected cAMP-independent protein kinase activity. The exposure of glioma cells or lymphocytes to 27 or 2450MHz fields caused dose dependent effects on proliferation. DNA synthesis was increased in glioma cells and suppressed in lymphocytes. Cell cycle alterations in CHO cells were induced by a 27MHz exposure. The major alteration was an increase in the number of cells in G0/G1, and a decrease of those in M phase. Cytogenetic damage has been reported in human lymphocytes from blood samples exposed to a 945MHz field. Very low power pulsed exposure of human amnion cells at 960MHz have recently been reported to induce a decrease in cell growth rate with increased exposure time.In our previous studies, we have demonstrated that low power microwave radiation can induce irreversible damage to rabbit lens epithelial cells (RLECs) in vivo. The aim of this study was to determine the effect of microwave radiation on primary cultured RLECs and lens, and related signal transduction mechanisms.Part ILow power microwave radiation inhibits the proliferation of rabbit lens epithelial cells by upregulating P27Kipl expressionObjectiveThe goal of this study was to examine the effects of low power microwave radiation (<10mW/cm2) on the proliferation of cultured rabbit lens epithelial cells (RLECs).MethodsCell culture: The rabbits used in this investigation were handled in compliance with the"Guiding Principles in the Care and Use of Animals" (DHEW Publication, N1H 86-23) andaccording to the tenets of the ARVO Statement for the Use of Animals in Ophthalmic andVision Research. 12-week-old rabbits weighing 1kg to 1.5kg were killed by CO2 inhalation.The entire eye was removed and dipped in 75% ethanol for 30 seconds, then it was opened from the posterior segment. The dissection procedure was performed with sterile instruments under a laminar flow hood. Lenses were dissected carefully by a posterior approach and washed three times in phosphate-buffered saline to remove attached pigments and vitreous. The capsule epithelium was dissected by fine forceps and placed in a 35-mm2 culture dish adhering to the plastic. Some drops of culture medium were applied to the epithelium specimens to prevent drying, and the dishes were put in a humidified CO2 incubator (5% CO2. 37C) for 6 hours to allow firm attachment of the capsules. Another 2 ml of culture medium was then added, and the capsules were left for 3 or 4 days before the fi...