조골세포에서 Peroxisome proliferators-activated receptor-g 작용제인 15-Deoxy-D12,14-prostaglandin J2의 Akt와 NF-κB 기전을 통한 인터루킨-6의 분비 억제 : The 15-Deoxy-D12,14 - prostaglandin J2, peroxisome proliferators-activated receptor-g agonist, inhibits interleukin-6 secretion in MC3T3E-1 osteoblasts via the Akt and NF-kB pathways

다국어 초록 (Multilingual Abstract)

ABSTRACT

The 15-Deoxy-D12,14-prostaglandin J2, peroxisome proliferators-activated receptor g agonist, inhibits interleukin-6 secretion in MC3T3E-1 osteoblasts via the Akt and NF-κB pathways

Ik-Su Park
(Advisor：Prof. Sang-Jun Park, M.D)
Department of Medicine
Graduate School, Inje University

Objective
Periodontitis is a chronic inflammatory disease that results in gingival inflammation and periodontal tissue destruction and is accompanied by alveolar bone resorption and eventual tooth loss. Gram-negative bacterium possesses and produces lipopolysaccharide (LPS) molecules that play a role in the production of interleukin-6 (IL-6) during inflammatory process, as well as in bone resorption. 15-deoxy-D12,14-prostaglandin J2 (15d-PGJ2), peroxisome proliferators-activated receptor gamma (PPARg) activator, has been shown to have anti-inflammatory effects. Therefore, we examined the effect of 15d-PGJ2 on production of IL-6 by stimulating mouse osteoblast-like cells with LPS.

Methods
This study investigated mRNA and protein expression of IL-6 using reverse transcription-polymerase chain reaction (RT-PCR) and sandiwich ELISA inMC3T3E-1 cells, respectively. I also investigated the transcription factor of IL-6 in MC3T3E-1 cellsusing electric mobility shift assay (EMSA). I identified the LPS-stimulated IL-6 expression is involved signal pathway using RT-PCR and Western blot analysis.

Results
Our results indicate that 15d-PGJ2 inhibits LPS-induced IL-6 production in a concentration-dependent manner in MC3T3E-1 cells, without appreciable cytotoxicity. To further examine the mechanism responsible for the inhibition of IL-6 production by 15d-PGJ2, we examined the effect of 15d-PGJ2 on nuclear factorkB (NFkB) activation and the phosphorylation of protein kinase B (Akt). 15d-PGJ2 treatment clearly reduced the DNA binding activity of NF-kB in LPS-stimulated MC3T3E-1 cells, an effect that was mediated by inhibiting the degradation of inhibitor kB (IkB) and nuclear translocation of NF-kB p65 subunit. In addition, 15d-PGJ2 attenuated the LPS-mediated Akt pathway. These effects of 15d-PGJ2 were not abrogated by the PPARg antagonist, GW9662, indicating that they are PPARg-independent actions.

Conclusion
Collectively, these results suggest that 15d-PGJ2 possess a potent suppressive effect on inflammatory responses of MC3T3E-1 via the Akt and NF-κB pathways independent of PPARg and suggest that thiscompound may offer some insight into the development of a new therapeutic approach to the prevention and treatment of periodontal diseases.

Key Words : Periodontitis 15-deoxy-D12,14-prostaglandin J2 Interleukin-6 Nuclear factor-κB Protein kinase B

국문 초록 (Abstract)

국문초록

조골세포에서 Peroxisome proliferators-activated receptor-g 작용제인 15-Deoxy-D12,14-prostaglandin J2의 Akt와 NF-κB 기전을 통한 인터루킨-6의 분비 억제


박익수
(지도교수: 박상준)
인제대학교 대학원
의학과


목 적
치주염은 만성 염증성 질환으로서 잇몸염증과 치아 주위 조직 파괴가 일어나며, 치조골 흡수로 결국에는 치아를 잃게 된다. 그람네거티브 박테리아가 분비하는 내독소는 염증반응뿐 만 아니라 치조골 흡수에 중요한 역할을 하는 인터루킨-6의 분비를 유도한다. 15-deoxy-D12,14-prostaglandin J2 (15d-PGJ2), peroxisome proliferators-activated receptor gamma-g (PPARg) activator의 항-염증효과는이미 밝혀져 있다. 따라서 본 저자는 마우스 15d-PGJ2 를 이용하여 내독소로 자극한 조골세포주에서 치주염과 관련된 인자인 인터루킨-6의 분비 조절의 효과와 기전을 알아보고자 한다.

방 법
15d-PGJ2의 치주염 억제 효과를 알아보기 위하여 마우스 조골세포주에 내독소로 자극하여 인터루킨-6를 sandwich ELISA와 RT-PCR로 발현 정도를 측정하였고, 인터루킨-6 발현에 관련된 조절 기전을 조사하였다.

결 과
마우스 조골세포주에서 인터루킨-6 발현에 대한 15d-PGJ2의 효과는 독성이 없이
농도 의존적이었다. 이러한 억제효과는 인터루킨-6의 발현은 새포내에서 Akt 기전과
NF-kB 핵전사인자를 통하여 조절 되어진다.

결 론
마우스 조골세포주에서 15d-PGJ2는 Akt 기전과 NF-kB 핵전사인자조절을 통하여 치주질환의 원인중의 하나인 인터루킨-6의 분비를 조절한다. 이러한 결과로서, 치주질환 예방과 치료에 15d-PGJ2의 적용 가능성을 제시한다.


주제어 : 치주염 15-deoxy-D12,14-prostaglandin J2 Interleukin-6 Nuclear factor-κB Protein kinase B

목차 (Table of Contents)

• Lists
• List of Figures
• 국문초록 i
• Abstract iii
• I. Introduction 1
• II. Objects 5
• III. Materials and Methods 6
• IV. Results 10
• V. Discussion 15
• VI. Conclusion 18
• References 19