DSS 유도 대장염 마우스 모델에서 Phillyrin의 대장상피세포 매개 항염증 효과 = The anti-inflammatory effects of phillyrin mediated by colonic epithelial cells in a DSS-induced colitis mouse model

다국어 초록 (Multilingual Abstract)

Phillyrin (PHI) is a lignan glycoside found mainly in the fruits and leaves of Forsythia suspensa, serving as the major active ingredient. PHI possesses various biological and pharmacological properties, such as anti-inflammatory, antiviral, anti-obesity, and antioxidant effects. However, its potential as a treatment for ulcerative colitis and the exact mechanism through which it acts remain uncertain. Therefore, the anti-inflammatory effect of PHI in dextran sulfate sodium (DSS)-induced colitis mice was investigated by in vitro and in vivo experiments. BALB/c mice were divided into six groups, and acute colitis was induced by administering 5% DSS in drinking water for 7 days. Five groups, excluding the control group, received daily oral doses of PHI (12.5, 25, and 50 mg/kg) or ASA (50 mg/kg) for one week. PHI reduced clinical symptoms, including body weight loss, colon shortening, disease activity, and mucosal damage. Histopathological analysis showed partial recovery of mucosal damage and crypt loss. Additionally, PHI reduced mRNA expression of pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-α as well as COX-2 and iNOS through the MAPK signaling pathway. The anti-inflammatory effect of PHI was also evaluated in HT-29 cells, where non-cytotoxic doses of PHI inhibited the mRNA expression of IL-1 β, IL-6, IL-8, and TNF-α after LPS stimulation. In conclusion, PHI shows anti-inflammatory activity in DSS-induced colitis and LPS-stimulated HT-29 cells, suggesting its potential as a treatment for ulcerative colitis.

국문 초록 (Abstract)

Phillyrin (PHI)은 연교(連翹; Forsythia suspensa Vahl)에서 발견되는 리그난 성분으로 주요 활성 성분으로 작용한다. PHI는 항염, 항바이러스, 항비만 및 항산화 효과와 같은 다양한 생물학적 및 약리적 특성을 가지고 있다. 그러나, 궤양성 대장염에서의 치료적 역할과 작용 기전은 아직 불분명하다. 따라서, 본 연구에서는 덱스트란 황산나트륨(DSS)으로 유도된 대장염 마우스에서 PHI의 항염 효과를 확인했다. BALB/c 마우스를 여섯 그룹으로 나누고, 7일 동안 음용수에 5% DSS를 투여하여 급성 대장염을 유도했다. 대조군을 제외한 다섯 그룹은 1주일 동안 PHI (12.5, 25 및 50 mg/kg) 또는 5-ASA (50 mg/kg)를 매일 경구 투여했다. PHI는 체중 감소, 대장 단축, 질병 활동 및 점막 손상을 포함한 임상 증상을 감소시켰다. 조직병리학적 분석은 점막 손상과 융기부 손실이 부분적으로 회복되었음을 보여주었다. 또한, PHI는 MAPK 신호전달경로를 통해 IL-1β, IL-6, TNF-α와 같은 염증성 사이토카인과 COX-2, iNOS의 mRNA 발현을 감소시켰다. PHI의 항염증 효과는 대장상피세포인 HT-29 세포에서도 확인되었다. 비세포독성 용량의 PHI는 LPS 자극 후 IL-1β, IL-6, IL-8, TNF-α의 mRNA 발현을 억제했다. 결론적으로, PHI는 DSS로 유도된 대장염 질환 모델과 LPS로 자극된 HT-29 세포에서 항염증 활성을 나타내어 궤양성 대장염 치료제로서의 잠재력을 시사한다.

목차 (Table of Contents)

• 1. Introduction 1
• 2. Materials and methods 4
• 2.1. Reagents and antibodies 4
• 2.2. Animals 4
• 2.3. Induction of mouse colitis model by DSS administration 5
• 2.4. Disease activity index (DAI) 5
• 2.5. Histological analysis 6
• 2.6. Cell culture 7
• 2.7. Assay of cell viability 7
• 2.8. Real-time reverse transcription-polymerase chain reaction (RT-PCR) 8
• 2.9. Western blot analysis 10
• 2.10. Statistical analysis 11
• 3. Results 12
• 3.1. Analysis of serum biochemical parameters in DSS-induced colitis mice 12
• 3.2. Effect of PHI on colon length shortening in DSS-induced colitis mice 14
• 3.3. Effect of PHI on body weight change in DSS-induced colitis mice 17
• 3.4. Effect of PHI on DAI in DSS-induced colitis mice 19
• 3.5. Effect of PHI intestinal tissue damage in DSS-induced colitis mice 21
• 3.6. Effects of PHI on IL-1β, IL-6, and TNF-α in DSS-induced colitis mice 23
• 3.7. Effect of PHI on the expression levels of
• pro-inflammatory mediators in DSS-induced colitis mice 27
• 3.8. Effect of PHI on the phosphorylation of MAPKs in DSS-induced colitis mice 30
• 3.9. Effect of PHI on the viability of HT-29 cells 32
• 3.10. Effect of PHI on the mRNA expression of
• pro-inflammatory cytokines in LPS-stimulated HT-29 cells 34
• 3.11. Effect of PHI on the expression levels of
• pro-inflammatory mediators in LPS-stimulated HT-29 cells 39
• 3.12. Effect of PHI on the phosphorylation of MAPKs in LPS-stimulated HT-29 cells 42
• 4. Discussion 44