Np. Rotstein et al., APOPTOSIS OF RETINAL PHOTORECEPTORS DURING DEVELOPMENT IN-VITRO - PROTECTIVE EFFECT OF DOCOSAHEXAENOIC ACID, Journal of neurochemistry, 69(2), 1997, pp. 504-513
When rat retinal cells are cultured in a serum-free medium, the photor
eceptor cells start dying after 7 days. The addition of docosahexaenoi
c acid (DHA) to the cultures prevents the selective death of photorece
ptors. Here it is shown that, unlike other retinal neurons, photorecep
tors die through an apoptotic pathway. Hallmarks of apoptosis, such as
nuclear fragmentation and condensation and DNA cleavage forming a lad
der pattern on an agarose gel, were observed. The timing and high sele
ctivity of the triggering of photoreceptor cell apoptosis suggest the
existence of a programmed cell death. Compared with other fatty acids,
DHA not only was the most effective in promoting photoreceptor surviv
al, but also the only one to decrease the number of apoptotic nuclei.
The results suggest that DHA is important among the factors preventing
apoptosis of photoreceptors in the developing retina. A limitation in
the availability of this fatty acid might trigger apoptosis as a resu
lt of the failure to develop functional photoreceptor outer segments.