Leukemia inhibitory factor is a key regulator of astrocytic, microglial and neuronal responses in a low-dose pilocarpine injury model.
Insult to the central nervous system (CNS) induces many changes, including altered neurotransmitter expression, activation of astrocytes and microglia, neurogenesis and cell death. Cytokines and growth factors are candidates to be involved in astrocyte and microglial activation, and the up-regulation of glial fibrillary acidic protein (GFAP) is associated with brain damage. One of these candidates is leukemia inhibitory factor (LIF), a pro-inflammatory cytokine that is induced in astrocytes by brain damage or seizure. LIF also regulates expression of both neuropeptide Y (NPY) and galanin following peripheral nerve injury. To test the hypothesis that LIF regulates astrocyte, microglial and neuropeptide responses to a mild insult, we used a low-dose pilocarpine model to induce a brief seizure in LIF knock-out (KO) mice. Compared to wild type mice, the LIF KO mouse displays reduced astrocyte and microglial activation in the hippocampus. In addition, LIF KO mice display dramatically altered NPY, but not galanin, expression in response to injury. Thus, LIF is required for normal glial responses to brain damage, and, as in the periphery, LIF regulates NPY expression in the CNS.
Holmberg
Kristina H
KH
Biology Division, California Institute of Technology, Pasadena, CA 91125, USA. kholmber@uic.edu
Patterson
Paul H
PH
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000502:physiology*; D005260:Female; D005784:Gene Amplification; D006624:Hippocampus / Q000502:physiology; D015850:Interleukin-6 / Q000172:deficiency / Q000235:genetics*; D053605:Leukemia Inhibitory Factor; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D017628:Microglia / Q000187:drug effects / Q000502:physiology*; D018721:Muscarinic Agonists / Q000633:toxicity; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D010862:Pilocarpine / Q000633:toxicity; D016133:Polymerase Chain Reaction
D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D018721:Muscarinic Agonists; D010862:Pilocarpine