Page 67 - Q. Neuroscience

Jeong-Min Hong, Ji-Hong Moon, Honghua Yin, Kazi Mohammad Ali Zinnah, Jong-Hoon Kim, Jae-Won
Seol and Sang-Youel Park*
College of Veterinary Medicine, Chonbuk National University, Jeonju, Jeonbuk 561-756, South Korea

BACKGROUND AIM

Prion diseases are fatal neurodegenerative disorders that are derived from Prion peptide–mediated neuroinflammation was attenuated by
accumulation of an abnormal prion protein (PrPSc) of prion protein in the calcineurin and autophagy inhibition, and also suggest
brains. Recent studies have illustrated that calcineurin could play an calcineurin and autophagy may be a possible target molecule in
important role in the calcium-calmodulin pathway to regulate nuclear factor anti-inflammation of neuron.
kappa B (NF-κB). Calcineurin is activated by the binding calcium to METHODS
calmodulin. In the present study, we examined the activation of calcineurin
and autophagy upon exposure to prion peptide and its role in prion peptide-  Cell culture
induced upregulation of nuclear factor-kappa B (NF-κB) and  PrP (106-126) treatment
proinflammatory cytokines including tumor necrosis factor (TNF)-α and  ELISA
interleukin (IL)-6 in human neuro carcinoma. The results indicate that prion  Immunocytochemistry
peptide induced calcineurin activation, which subsequently lead to the  Western blot assay
activation of NF-κB transcription factor. Calcineurin activation increased  Calcineurin activity assay
the expression of TNF-α and IL-6, which blocked by treatment with  Fluorescence microscopy analysis
calcineurin and autophagy inhibitors.  Statistical analysis
RESULTS

A p- NF-κB A B
β-actin B p- NF-κB p- NF-κB
PrP(μM) 25 50 100 A 250 ** β-actin β-actin
200
calcineurin 150
PrP
PrP
B β-actin Calcineurin activity (pmol/μg protein) 100 FK506 siPPP3CB
PrP(μM) 25 50 100 50 NC
PrP(μM) 0 25 50 100
C
C
PrP(μM) 50 100 calcineurin D 250 ***
C *** *** D 1.5 ** ** ** β-actin PrP 200 *
150
PrP
IL-6 mRNA expression (ΔΔCt) 1.5 1.0 0.5 *** TNF alpha mRNA expression (ΔΔCt) 1.0 0.5 FK506 Calcineurin activity (pmol/μg protein) 100 50 0 *** *** *** FK506 ***
PrP
0.0 0.0 FK506 150 *** E 150 ***
PrP(μM) 25 50 100 PrP(μM) 25 50 100 E D ***
calcineurin TNF-α expression (pg/ml) 100 *** ***
E 200 *** *** *** *** *** *** β-actin PrP Il-6expression (pg/ml) 100 50 *** *** 50
siPPP3CB
IL-6 expression (pg/ml) 150 50 TNF-α expression F 150 50 NC FK506 0 FK506 0
(pg/ml) 100
100
PrP
PrP
0 0
PrP(μM) 25 50 100 PrP(μM) 25 50 100
Figure 2. Prion protein induced calcineurin activation. Figure 3. Calcineurin inhibition alleviated p-NF-κB-mediated
Figure 1. Prion protein increased p-NF-κB-mediated inflammation. inflammation.
A
A p- NF-κB B P62
P62 LC-3
β-actin
LC-3 β-actin calcineurin
PrP
β-actin CQ PrP
CQ
PrP(μM) 25 50 100
C
B
P62
Autophagy
LC-3
PrP
β-actin CQ
PrP
FK506
IL-6 expression (pg/ml) 250 TNF-α expression (pg/ml) 150 50 *** ***
D ** *** E ***
C 200 *** *** 100 *** NF-kb
150
100
PrP 50 0 PrP 0
CQ
CQ
PrP
FK506 Neuro
inflammation
Figure 4. Abrogation of calcineurin activation induced autophagy Figure 5. Inhibition of autophagy alleviated p-NF-κB driven
inactivation. proinflammation by prion protein.
CONCLUSION Contact information
 PrP (106-126) induces calcineurin activation, and calcineurin functions as an upstream E-mail: als93030@naver.com
mediator of NF-κB activation. Tel: 010-9918-9235
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