Neuronal death in cytokine-activated primary human brain cell culture: role of tumor necrosis factor-alpha.
We examined cytokine-mediated neuronal death in neuron-astrocyte cultures from second trimester human fetal cerebrum. In these cultures, high-output inducible nitric oxide synthase (NOS) and tumor necrosis factor-alpha (TNFalpha) are expressed in astrocytes after exposure to IL-1beta/IFNgamma. Neuronal cell death was evident at >/=48 h following cytokine stimulation. Neutralizing anti-TNFalpha antiserum inhibited ( approximately 48%) neurotoxicity in IL-1beta/IFNgamma-treated cultures, demonstrating a role for endogenously produced TNFalpha. Interestingly, the degree of neuroprotection conferred by superoxide dismutase or N-methyl D-aspartate (NMDA) receptor antagonists in these cultures was smaller and variable. Similarly, the effect of the NOS inhibitor, N(G)-monomethyl L-arginine (NMMA) on IL-1beta/IFNgamma-induced neuronal death was variable, showing no statistically significant effect when results from more than 30 independent cultures were averaged. Neurons die by apoptosis in cytokine-treated human fetal CNS cultures as shown by the characteristic nuclear morphology as well as positive labeling for TUNEL. Our results demonstrate a potent neurotoxicity mediated by the cytokine combination IL-1beta/IFNgamma in primary human neuron-astrocyte cultures and a crucial role for endogenous TNFalpha in mediating neurotoxicity in this system. These results firmly establish the neurotoxic potential of the inflammatory cytokines IL-1beta and TNFalpha in the human CNS.
Downen
M
M
Department of Pathology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Amaral
T D
TD
Hua
L L
LL
Zhao
M L
ML
Lee
S C
SC
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D001253:Astrocytes / Q000737:chemistry* / Q000187:drug effects / Q000502:physiology*; D002452:Cell Count; D018929:Cell Culture Techniques; D005333:Fetus / Q000166:cytology; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007375:Interleukin-1 / Q000494:pharmacology / Q000502:physiology / Q000633:toxicity; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D009498:Neurotoxins / Q000378:metabolism; D009569:Nitric Oxide / Q000502:physiology / Q000633:toxicity; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000502:physiology; D013482:Superoxide Dismutase / Q000633:toxicity; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects / Q000378:metabolism* / Q000633:toxicity; D014443:Tyrosine / Q000031:analogs & derivatives / Q000187:drug effects / Q000378:metabolism
D007375:Interleukin-1; D009498:Neurotoxins; D016194:Receptors, N-Methyl-D-Aspartate; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine; D019001:Nitric Oxide Synthase; D013482:Superoxide Dismutase