Differential regulation of intestinal stem cell proliferation depending on the type of AhR ligands
- 주제(키워드) Intestinal stem cell (ISC) , Aryl hydrocarbon receptor (AhR) , Proliferation , Intestinal epithelial cells (IECs) , 6-Formylindolo[3 , 2-Ь] carbazole (FICZ) , 2 , 3 , 7 , 8-tetrachlorodibenzo-ρ-dioxin (TCDD)
- 주제(DDC) 651.1
- 발행기관 아주대학교
- 지도교수 장선영
- 발행년도 2023
- 학위수여년월 2023. 8
- 학위명 석사
- 학과 및 전공 일반대학원 바이오헬스규제과학과
- 실제URI http://www.dcollection.net/handler/ajou/000000032948
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
The gut epithelial barrier is important to maintain intestinal homeostasis to protect from antigens, that exist in the lumen. When the epithelial barrier is weakened, bacterial translocation can progress, causing inflammatory bowel disease. The aryl hydrocarbon receptor (AhR) is an important environmental sensor that maintains the intestinal epithelial barrier. AhR ligands are diverse and largely classified into endogenous and exogenous ligands. The AhR exhibited different functions depending on the type of ligands. This study revealed the effects of endogenous and exogenous ligands on the proliferation of intestinal stem cells (ISC). 2,3,7,8tetrachlorodibenzo-ρ-dioxin (TCDD) was used as an exogenous ligand and 6Formylindolo[3,2-Ь] carbazole (FICZ) was used as an endogenous ligand. To investigate the function of AhR in intestinal epithelial cells, 3D culture was utilized to mimic the actual intestinal environment. It was found that FICZ decreased the growth of organoids, while TCDD did not exert such effects. Also, FICZ decreased the proliferation of ISC, whereas TCDD did not. Besides, TCDD disrupted the regulatory effects of FICZ on the organoids. In contrast to the results observed in organoids, in the in vivo system, FICZ increased the proliferating cells, while TCDD did not exhibit the same effect. These results indicated that under normal conditions, proliferation control by AhR ligands did not occur significantly. However, when the environment worsens, FICZ regulated epithelial cell proliferation while TCDD did not. Moreover, these findings implied that in the presence of cancer, the effect of AhR ligands on epithelial cells might differ, indicating that different effects on carcinogenesis depend on the type of AhR ligands.
more목차
Ⅰ. INTRODUCTION 1
Ⅱ. MATERIALS AND METHODS 4
1. Mice 4
2. Gut organoid 4
3. RNA extraction 5
4. Real-time PCR 6
5. Immunofluorescence 6
6. Fluorescence intensity 7
7. SRB (Sulforhodamine B) assay 8
8. Statics 8
Ⅲ. RESULTS 13
A. FICZ suppressed the growth of organoids originating from the mouse small intestine. 13
B. Different types of AhR ligands led to alterations in the AhR signaling pathway and function of differentiated cells in the small intestine organoids. 16
C. FICZ decreased the number of proliferating cells. 18
D. FICZ suppressed the growth of colonoids. 20
E. Different types of AhR ligands led to alterations in the AhR signaling pathway and function of differentiated cells in the colonoids. 22
F. TCDD interfered with the effects of FICZ on the growth of organoids. 24
G. The interference of TCDD affected the AhR signaling pathway and function of differentiated cells. 26
H. Summary of organoid results. 28
I. The effects of AhR ligands in the small intestine. 29
J. The effects of AhR ligands in the colon upstream. 32
K. The effects of AhR ligands in the colon rectal. 34
Ⅳ. DISCUSSION 36
Ⅴ. CONCLUSION 41
REFERENCES 43
KOREAN ABSTRACT 46
