CKD-712, (S)-1-(alpha-naphthylmethyl)-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline, Inhibits the NF-kappaB Activation and Augments Akt Activation during TLR4 Signaling

Since CKD-712 has been developed as an anti-inflammatory agent, we examined the effect of CKD-712 during TLR4 signaling. Using HEK293 cells expressing TLR4, CKD-712 was pre-treated 1 hr before LPS stimulation. Activation of NF-kappaB was assessed by promoter assay. The activation of ERK, JNK, p38, IRF3 and Akt was measured by western blotting. CKD-712 inhibited the NF-kappaB signaling triggered by LPS. The activation of ERK, JNK, p38 or IRF3 was not inhibited by CKD-712. On the contrary the activation of these molecules was augmented slightly. The activation of Akt with stimulation of LPS was also enhanced with CKD-712 pre-treatment at lower concentration, but was inhibited at higher concentration. We suggest that during TLR4 signaling CKD-712 inhibits NF-kappaB activation. However, CKD-712 augmented the activation of Akt as well as Map kinases. Therefore, we suggest that CKD-712 might have a role as an immunomodulator.

Human Brain Astrocytes Mediate TRAIL-mediated Apoptosis after Treatment with IFN-gamma

TNF-related apoptosis inducing ligand (TRAIL) expressions were studied in primary human brain astrocytes in response to pro-inflammatory cytokines. When astrocytes were treated with IL-1beta TNF-alphaor IFN-gamma TRAIL was induced in cultured fetal astrocytes. In particular, IFN-gammainduced the highest levels of TRAIL in cultured astrocytes. When astrocytes were pre-reated with IFN-gamma they induced apoptosis in TRAIL-sensitive Peer cells. Our results suggest that IFN-gamma modulates the expression of TRAIL in astrocytes, which may enhance cytotoxic sensitivity of infiltrating immune cells or brain cells other than astrocytes during inflammation of brain.

Human Brain Astrocytes Mediate TRAIL-mediated Apoptosis after Treatment with IFN-gamma

TNF-related apoptosis inducing ligand (TRAIL) expressions were studied in primary human brain astrocytes in response to pro-inflammatory cytokines. When astrocytes were treated with IL-1beta TNF-alphaor IFN-gamma TRAIL was induced in cultured fetal astrocytes. In particular, IFN-gammainduced the highest levels of TRAIL in cultured astrocytes. When astrocytes were pre-reated with IFN-gamma they induced apoptosis in TRAIL-sensitive Peer cells. Our results suggest that IFN-gamma modulates the expression of TRAIL in astrocytes, which may enhance cytotoxic sensitivity of infiltrating immune cells or brain cells other than astrocytes during inflammation of brain.

IFN-gamma Regulates Expression of BRG1 Associated Factor 155/170 and Sensitivity to Steroid in Astrocytes

BACKGROUND: The expression of BRG1 associated factors (BAF) 155 and BAF 170 in response to IFN-gamma or TNF-alpha was studied in astrocytoma cell lines and primary astrocytes. BAFs are complexed with BRG1 and are also associated with activated glucocorticoid for glucocorticoid trans-activation. METHODS: IFN-gamma was pretreated for 18 hrs and cells were incubated with IL-1 or TNF-alpha for 72 hrs or 96 hrs with different concentrations of steroid. Cell death was measured by LDH assay. BAF expression was assayed by RT-PCR. RESULTS: IFN-gamma increased cell death by dexamethasone in LN215 cells but not in LN319 cells. The IFN-gamma increased the expression of BAF 155 and BAF 170 in adult astrocytes and LN215 cells, but IFN-gamma decreased the expression of BAF 155/170 in LN319 cells. The effect of IFN-gamma on the expression of BAF was not as clear in fetal astrocytes as it was in adult astrocytes. CONCLUSION: Our results suggest cytokines produced during immune reaction or immunotherapy may modulate steroid susceptibility of astrocytes and astrocytoma cells by influencing the expression of BAFs.