| First Author | Cardenas H | Year | 2003 |
| Journal | Brain Res | Volume | 985 |
| Issue | 1 | Pages | 89-97 |
| PubMed ID | 12957371 | Mgi Jnum | J:85581 |
| Mgi Id | MGI:2675776 | Doi | 10.1016/s0006-8993(03)03172-x |
| Citation | Cardenas H, et al. (2003) Compromised reactive microgliosis in MPTP-lesioned IL-6 KO mice. Brain Res 985(1):89-97 |
| abstractText | Reactive gliosis, the cellular manifestation of neuroinflammation, is a pathological hallmark of neurodegenerative diseases including Parkinson's disease. The persistent gliosis observed in the Parkinson's disease substantia nigra (SN) and in humans and animals exposed to the neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) may represent a chronic inflammatory response that contributes to pathology. We have previously shown that in the absence of interleukin-6 (IL-6) dopaminergic neurons are more vulnerable to MPTP. Since IL-6 is both an autocrine and paracrine proliferation factor for CNS glia, we investigated reactive gliosis in MPTP-lesioned IL-6 (-/-) mice. While astrogliosis was similar in injured IL-6 (+/+) and IL-6 (-/-) SN pars compacta (pc), microgliosis was severely compromised in IL-6 (-/-) mice. In the absence of IL-6, an acute reactive microgliosis was transient with a complete absence of reactive microglia at day 7 post-lesion. Extensive reactive microgliosis was observed in the SNpc of MPTP-lesioned IL-6 (+/+) mice. Because glial derived inducible nitric oxide synthase (iNOS) has been implicated in dopaminergic cell death, we examined glial iNOS expression in the IL-6 genotypes to determine if it correlated with the greater vulnerability and reduced microgliosis observed in the MPTP-lesioned IL-6 (-/-) nigrostriatal system. Both reactive microglia and astrocytes expressed iNOS in the lesioned SNpc. In the IL-6 (-/-) mice, microglial iNOS expression diminished as reactive microgliosis declined. The data suggest IL-6 regulation of microglia activation, while iNOS expression appears to be secondary to cell activation. |
