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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Animals, Newborn, Blotting, Western, Cell Nucleus, Cells, Cultured, Chromones, Electrophoresis, Polyacrylamide Gel, Enzyme Inhibitors, Glyceraldehyde-3-Phosphate Dehydrogenases, Morpholines, NF-kappa B, Osteoblasts, Oxazoles, Phosphatidylinositol 3-Kinases, Phosphoprotein Phosphatases, Phosphorylation, Proto-Oncogene Proteins c-akt, RNA, Messenger, Rats, Rats, Wistar, Reverse Transcriptase Polymerase Chain Reaction, Signal Transduction, Time Factors, Tumor Necrosis Factor-alpha.
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Does pI3K/Akt mediate expression of TNF-alpha mRNA and activation of NF-kappaB in calyculin A-treated primary osteoblasts? Context: The effect of calyculin A (CA), a serine/threonine protein phosphatase inhibitor, on tumor necrosis factor-alpha (TNF-alpha) in primary osteoblasts was investigated to determine whether protein phosphatases could affect primary osteoblasts and if so which signaling pathways would be involved. Primary osteoblasts were prepared from newborn rat calvaria. Cells were treated with 1 nM CA for different time periods. The expressions of TNF-alpha and GAPDH mRNA were determined by RT-PCR. Cell extracts were subjected to SDS-PAGE and the activation of Akt and NF-kappaB were analyzed by western blotting. Calyculin A-treatment markedly increased the expression of TNF-alpha mRNA and enhanced the phosphorylation level of Akt (Ser473) in these cells. Pretreatment with the PI3K inhibitor LY294002 suppressed the increase in TNF-alpha mRNA expression and the phosphorylation of Akt in response to CA. Western blot analysis showed that CA stimulated the phosphorylation and nuclear translocation of NF-kappaB in primary osteoblasts, and these responses were blocked by pretreatment with LY294002.
assistant
Calyculin A elicits activation of PI3K/Akt pathway which leads to expression of TNF-alpha mRNA and activation of NF-kappaB. This NF-kappaB activation involves both phosphorylation and nuclear translocation of NF-kappaB. Final Decision: yes