Differential effects of Th1, monocyte/macrophage and Th2 cytokine mixtures on early gene expression for molecules associated with metabolism, signaling and regulation in central nervous system mixed glial cell cultures.
BACKGROUND
Cytokines secreted by immune cells and activated glia play central roles in both the pathogenesis of and protection from damage to the central nervous system (CNS) in multiple sclerosis (MS).


METHODS
We have used gene array analysis to identify the initial direct effects of cytokines on CNS glia by comparing changes in early gene expression in CNS glial cultures treated for 6 hours with cytokines typical of those secreted by Th1 and Th2 lymphocytes and monocyte/macrophages (M/M).


RESULTS
In two previous papers, we summarized effects of these cytokines on immune-related molecules, and on neural and glial related proteins, including neurotrophins, growth factors and structural proteins. In this paper, we present the effects of the cytokines on molecules involved in metabolism, signaling and regulatory mechanisms in CNS glia. Many of the changes in gene expression were similar to those seen in ischemic preconditioning and in early inflammatory lesions in experimental autoimmune encephalomyelitis (EAE), related to ion homeostasis, mitochondrial function, neurotransmission, vitamin D metabolism and a variety of transcription factors and signaling pathways. Among the most prominent changes, all three cytokine mixtures markedly downregulated the dopamine D3 receptor, while Th1 and Th2 cytokines downregulated neuropeptide Y receptor 5. An unexpected finding was the large number of changes related to lipid metabolism, including several suggesting a switch from diacylglycerol to phosphatidyl inositol mediated signaling pathways. Using QRT-PCR we validated the results for regulation of genes for iNOS, arginase and P glycoprotein/multi-drug resistance protein 1 (MDR1) seen at 6 hours with microarray.


CONCLUSIONS
Each of the three cytokine mixtures differentially regulated gene expression related to metabolism and signaling that may play roles in the pathogenesis of MS, most notably with regard to mitochondrial function and neurotransmitter signaling in glia.
Lisak
Robert P
RP
Department of Neurology, 8D University Health Center, Wayne State University School of Medicine, 4201 St Antoine, Detroit, MI, 48210, USA. rlisak@med.wayne.edu
Benjamins
Joyce A
JA
Bealmear
Beverly
B
Nedelkoska
Liljana
L
Studzinski
Diane
D
Retland
Ernest
E
Yao
Bin
B
Land
Susan
S
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000818:Animals; D001119:Arginase / Q000378:metabolism; D002478:Cells, Cultured; D002490:Central Nervous System / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism / Q000494:pharmacology*; D004075:Diglycerides / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000378:metabolism*; D017628:Microglia / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D009414:Nerve Growth Factors / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D050637:Receptors, Dopamine D3 / Q000378:metabolism; D017476:Receptors, Neuropeptide Y / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D018417:Th1 Cells / Q000166:cytology / Q000378:metabolism*; D018418:Th2 Cells / Q000166:cytology / Q000378:metabolism*
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D016207:Cytokines; D004075:Diglycerides; D036341:Intercellular Signaling Peptides and Proteins; D009414:Nerve Growth Factors; D050637:Receptors, Dopamine D3; D017476:Receptors, Neuropeptide Y; C100568:neuropeptide Y5 receptor; D052247:Nitric Oxide Synthase Type II; D001119:Arginase