Autocrine activation of cultured macrophages by brain-derived neurotrophic factor.
To elucidate a significance of the expression of brain-derived neurotrophic factor (BDNF) in the activated microglia/macrophages of the injured central nervous system, we examined BDNF actions on or BDNF synthesis by macrophages cultured from the mouse peritoneal cavity. They synthesized BDNF and neurotrophin-3 (NT-3) in addition to expressing high-affinity neurotrophin receptors, full-length TrkB (FL), truncated TrkB (TK(-)), and TrkC, thus suggesting an autocrine influence of BDNF and NT-3. BDNF, but not NT-3, enhanced phagocytic activity and stimulated synthesis/secretion of interleukin-1beta in the same manner as lipopolysaccharide (LPS). Furthermore, there was a significant correlation of the phagocytic activity with the expression of BDNF or TrkB (FL). These results imply that the phagocytic activity of macrophages depends on BDNF synthesis and/or TrkB (FL) expression, suggesting that BDNF participates in the activation processes of macrophages by acting in an autocrine manner.
Asami
Toshio
T
Laboratory of Molecular Biology, Gifu Pharmaceutical University, 5-6-1, Mitahora-Higashi, Gifu 502-8585, Japan.
Ito
Takuya
T
Fukumitsu
Hidefumi
H
Nomoto
Hiroshi
H
Furukawa
Yoshiko
Y
Furukawa
Shoei
S
D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000008:administration & dosage* / Q000378:metabolism*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D007375:Interleukin-1 / Q000378:metabolism*; D008262:Macrophage Activation; D008264:Macrophages / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D020933:Neurotrophin 3 / Q000008:administration & dosage*; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*
D019208:Brain-Derived Neurotrophic Factor; D007375:Interleukin-1; D020933:Neurotrophin 3