Novel polyhydroxylated fullerene suppresses intracellular oxidative stress together with repression of intracellular lipid accumulation during the differentiation of OP9 preadipocytes into adipocytes

Abstract

Along with differentiation of mouse stromal preadipocytes OP9 into adipocytes, intracellular ROS, especially superoxide anion radicals detected by NBT reduction assay, were found to appreciably increase, mainly in cytoplasmic area, parallelling with increases in intracellular lipid-droplet accumulation, whereas undifferentiated OP9 cells kept lower levels of ROS and lipid-droplets. β-Carotene bleaching assay showed that super-highly hydroxylated fullerene (SHH-F; C₆₀ (OH)₄₄) exerted higher antioxidant ability than highly hydroxylated fullerene (HH-F; C₆₀ (OH)_32–34) or lowly hydroxylated fullerene (LH-F; C₆₀ (OH)_6–12). Differentiation-dependent lipid-droplet accumulation was suppressed by SHH-F or HH-F more efficiently than LH-F. Furthermore, SHH-F significantly repressed intracellular ROS generation accompanied by adipocyte differentiation. Thus, lipid-droplet accumulation was shown to positively correlate with ROS upon the differentiation of OP9 preadipocytes into adipocytes and SHH-F significantly suppressed intracellular ROS together with repression of intracellular lipid accumulation.

Keywords::

• Fullerenol
• adipocytes
• lipid accumulation
• reactive oxygen species
• antioxidative activity
• differentiation

Declaration of interest: This work was performed as a part of the Research and Development Project of Industrial Science and Technology Frontier Program supported as a grant-in aid by NEDO (New Energy and Industrial Technology Development Organization), Japan, to N.M.

This paper was first published online on Early online on 2 July 2010.