Fig. 2.
Vitamin K1 and menaquinone-4 completely abolish oxidative pre-OL death. A: Vitamin K1 and MK-4 prevent arachidonic acid-induced pre-OL death in a concentration-dependent manner. Pre-OLs were challenged with arachidonic acid (100 μM) in the presence of increasing concentrations of K1 or MK-4 for 24 hr, and cell survival was determined as described. B: Representative phase-contrast images of pre-OLs treated as indicated for 20–24 hr. Pre-OLs were treated with arachidonic acid (100 μM) in the absence or presence of K1 (1 μM) and MK-4 (0.1 μM) as indicated. Data are representative of at least three experiments. Scale bar = 50 μm.