Protein kinase Czeta (PKCzeta) regulates ocular inflammation and apoptosis in endotoxin-induced uveitis (EIU): signaling molecules involved in EIU resolution by PKCzeta inhibitor and interleukin-13.
We show that inhibitory effect of interleukin-13 on endotoxin-induced uveitis in the Lewis rat is dependent on signaling activity of protein kinase Czeta (PKCzeta). To understand the effect of interleukin-13 or PKCzeta inhibitor treatment, the activation status of rat bone marrow-derived macrophages was studied in vitro. At 6 hours, lipopolysaccharide-stimulated macrophages produced tumor necrosis factor-alpha (TNF-alpha) with nuclear factor kappaB (NF-kappaB)/p65 expression. Treatment led to absence of NF-kappaB/p65 expression and low levels of TNF-alpha, suggesting accelerated inactivation of macrophages. At 24 hours after lipopolysaccharide stimulation, nuclear NF-kappaB/p65 decreased and nuclear NF-kappaB/p50 increased, associated with nuclear BCL-3 and a low level of TNF-alpha, indicating onset of spontaneous resolution. Treatment limited PKCzeta cleavage, with expression of nuclear NF-kappaB/p50 and BCL-3 and low nuclear NF-kappaB/p65 promoting macrophage survival, as evidenced by Bcl-2 expression. At 24 hours, intraocular treatment decreased membranous expression of PKCzeta by ocular cells, reduced vascular leakage with low nitric-oxide synthase-2 expression in vascular endothelial cells, and limited inflammatory cell infiltration with decreased intraocular TNF-alpha, interleukin-6, and nitric-oxide synthase-2 mRNA. Importantly, treatment decreased nuclear NF-kappaB/p65, increased transforming growth factor-beta2, and reduced caspase 3 expression in infiltrating macrophages, implying a change of their phenotype within ocular microenvironment. Treatment accelerated endotoxin-induced uveitis resolution through premature apoptosis of neutrophils related to high expression of toll-like receptor 4 and caspase 3.
de Kozak
Yvonne
Y
INSERM U598, Centre Biomédical des Cordeliers, 15, rue de l'Ecole de Medecine 75270, Paris cedex 06, France. ydekozak@ccr.jussieu.fr
Omri
Boubaker
B
Smith
Justine R
JR
Naud
Marie-Christine
MC
Thillaye-Goldenberg
Brigitte
B
Crisanti
Patricia
P
D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D015153:Blotting, Western; D053148:Caspase 3 / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D005123:Eye / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D005136:Eye Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D007249:Inflammation / Q000473:pathology / Q000503:physiopathology* / Q000517:prevention & control; D018793:Interleukin-13 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000633:toxicity; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008297:Male; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D015398:Signal Transduction / Q000187:drug effects; D051197:Toll-Like Receptor 4 / Q000378:metabolism; D051996:Transcription Factor RelA / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D014605:Uveitis / Q000139:chemically induced / Q000503:physiopathology* / Q000517:prevention & control; D000099221:Protein Kinase C zeta
D053148:Caspase 3; D016207:Cytokines; D005136:Eye Proteins; D018793:Interleukin-13; D008070:Lipopolysaccharides; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites; D011493:Protein Kinase C; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D051197:Toll-Like Receptor 4; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D000099221:Protein Kinase C zeta; C493487:Tlr4 protein, mouse