Lab Anim Res.  2010 Sep;26(3):311-314. 10.5625/lar.2010.26.3.311.

Focal Cerebral Ischemia Induces Decrease of Astrocytic Phosphoprotein PEA-15 in Brain Tissue and HT22 Cells

• Koh PO

• KMID: 2312083
• DOI: http://doi.org/10.5625/lar.2010.26.3.311

Abstract

PEA-15 is a small phosphoprotein (15 kDa) that is enriched in brain astrocytes. PEA-15 acts as an important modulator of cellular function including apoptosis and signal integration. This study investigated the expression of PEA-15 in focal cerebral ischemic injury. Cerebral ischemia was surgically induced in adult male rats by middle cerebral artery occlusion (MCAO), and brains were collected 24 hr after MCAO. A proteomic approach demonstrated decreases of PEA-15 protein spots in MCAO-operated animals in comparison to sham-operated animals. Western blot analysis clearly demonstrated that MCAO induces decreases in PEA-15 levels. We previously showed that glutamate toxicity induces cell death in a hippocampus-derived cell line (HT22). Glutamate exposure induces decreases of PEA-15 levels in HT22 cells. The results of this study suggest that focal cerebral ischemia induces cell death through downregulation of PEA-15 protein.

Keyword

HT22 cells; middle cerebral artery occlusion; PEA-15

MeSH Terms

Adult
Animals
Apoptosis
Astrocytes
Blotting, Western
Brain
Brain Ischemia
Cell Death
Cell Line
Down-Regulation
Glutamic Acid
Humans
Infarction, Middle Cerebral Artery
Male
Rats
Glutamic Acid

Figure

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  Figure 1. PEA-15 protein spots identified by MALDI-TOF. Arrows indicate the protein spots. The intensity of spots was measured using PDQuest software. The ratio of intensity is described as spots intensity of MCAO-operated animal to spots intensity of sham-operated animal. Data are shown as mean± S.E.M. ∗P<0.05 (vs. Sham). Mw and IP indicate molecular weight and isoelectrical point, respectively.

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  Figure 2. Western blot analysis of PEA-15 in the cerebral cortex from sham-operated and MCAO-operated animals. Each lane represents an individual experimental animal. Densitometric analysis of PEA-15 levels is represented as intensity of PEA-15 to intensity of actin. Data are shown as mean±S.E.M. ∗P<0.05 (vs. Sham).

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  Figure 3. Western blot analysis of PEA-15 in HT22 cells. Vehicle or glutamate (5 mM) was exposed to HT22 cells for 24 hr. Each lane represents an individual experimental animal. Densitometric analysis of PEA-15 levels is represented as intensity of PEA-15 to intensity of actin. Data are shown as mean±S.E.M. ∗P<0.05 (vs. Vehicle).

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