Nerve growth factor induces proliferation and enhances fiber regeneration in oligodendrocytes isolated from adult pig brain.

Mature oligodendrocytes (OL) isolated from adult pig brains start to regenerate their fibers after 4-5 days in vitro (DIV); after 14 DIV a network of OL fibers is formed. Growth factors, of which it was known that they play an important part during proliferation and differentiation of OL progenitor cells, were used to study their influence on the regeneration of mature OL. For this purpose, OL were treated at 6 DIV with different concentrations of various growth factors. At 24 h intervals the [3H]thymidine incorporation was measured and at 8 DIV the OL fiber production evaluated. None of these factors did influence the regenerative process to any significant extent except nerve growth factor (NGF). For the first time it could be shown that NGF enhanced the OL fiber regeneration considerably and induced the proliferation of a subset of OL. These results may have important implications for the remyelinating process in demyelinating diseases such as multiple sclerosis.