BIOLOGICAL EFFECTS OF EXTREMELY LOW-FREQUENCY MAGNETIC FIELDS ON STIMULATED MACROPHAGES J774.2 IN CELL CULTURE

Abstract

Studies with cell cultures indicate that extremely low-frequency magnetic fields may exert distinct biological effects on cellular systems. In the present study, selected biological effects of such magnetic fields are investigated in mammalian J774.2 macrophages in culture. J774.2 murine macrophages were exposed to extremely low-frequency magnetic field (ELF-MF) (25 Hz), and stimulated by lipopolysaccharide (LPS) and/or interferon-γ (IFN-γ). The generation of nitrite (NO₂⁻), prostaglandin-E₂ (PGE₂), tumor necrosis factor-alpha (TNF-α), chemiluminescence, and proteins were measured. While 1.5 mT and 25 Hz frequency did not affect the viability of the cells, higher flux density (2.4 mT) impaired it significantly. A 24-h exposure of the cells to such frequencies increased their chemiluminescence count rate and TNF-α levels, but not their PGE₂, NO₂⁻, or protein concentrations. These results demonstrate that exposure of J774.2 cells to extremely low-frequency magnetic field, at certain flux densities, decreases cell viability and may have biological significance in the antitumoricidal effect of such magnetic fields.

• J774.2 macrophages
• Extremely low-frequency magnetic field
• Free radicals
• Nitric oxide
• TNF-α
• Cell viability