Effect of pathogenic bacteria and natural products on intestinal permeability of Caenorhabditis elegans.
- 발행기관 강릉원주대학교 일반대학원
- 발행년도 2021
- 학위수여년월 2022. 2
- 학위명 석사
- 학과 및 전공 도움말 일반대학원 KIST강릉분원학.연협동과정
- 실제URI http://www.dcollection.net/handler/kangnung/000000011116
- UCI I804:42001-000000011116
- 본문언어 영어
초록/요약 도움말
장내에서 발생하는 과도한 염증은 장 투과도의 기능장애 (intestinal permeability dysfunction) 를 유발하며, 이는 다양한 염증성 장질환 (inflammatory bowel disease, IBD)의 발생에 영향을 준다. 예쁜꼬마선충 (Caenorhabditis elegans) 은 투명한 모델 선충으로, 유전자 정보가 잘 분석되어 있고, 수명 주기가 짧으며, 포유동물 모델에 비해 생명윤리 측면에서 장점을 가지고 있어, 다양한 생물학 연구에 이용된다. 본 연구에서는 예쁜꼬마선충 모델에서fluorescein isothiocyanate-dextran의 체내 투과도를 측정함으로써, 장 투과도의 표현형 지표로 사용하였다. 염증성 장질환을 모사한 증가된 장 투과도를 가진 선충에서는 대조군보다 높은 fluorescein isothiocyanate형광이 선충의 체내에서 관찰되었다. 반면 건강한 선충에서는 형광이 관찰되지 않았다. 이러한 실험 방법을 사용하여 다양한 병원성 세균이 예쁜꼬마선충의 장 투과도에 미치는 영향을 확인하였다. 6개의 유해세균 중 Pseudomonas aeruginosa, Aggregatibacter actinomycetemcomitans, Aeromonas hydrophila가 뚜렷하게 예쁜꼬마선충의 장 투과도를 증가시켰다. 다음으로 유해균에 의해 증가된 장 투과도에 대하여 천연물의 보호 효능을 확인하였다. 그 결과, schisandrin C가 위의 3가지 유해균에 의해 증가된 장 투과도를 가장 효과적으로 회복시켰으며, 홍국 에탄올 추출물은 P. aeruginosa 배양 상층액에 의한 장 투과도 손상에 대하여 회복 효능을 보였다 그러므로 schisandrin C와 홍국 에탄올 추출물은 염증성 장질환을 개선시키는 천연물 후보 물질로 유용하게 사용될 수 있을 것이다.
more초록/요약 도움말
In living organisms, severe inflammation in gut results in intestinal permeability dysfunction, which is one of the major influences of inflammatory bowel diseases (IBDs). Caenorhabditis elegans has known as a transparent tiny roundworm with a well-mapped genetic system, rapid lifecycle, non-ethical issue, thus, playing as a powerful model to investigate numerous biological processes. In this study, fluorescein isothiocyanate-dextran permeability in the intestine of nematode C. elegans was measured as a phenotypic determination of gut-permeability in which strong fluorescence intensity exhibits severe gut permeability dysfunction, mimicking IBD conditions while non-fluorescence intensity represents a healthy gut condition. Using this method, the detrimental effect of several pathogenic bacteria on intestinal permeability of C. elegans was evaluated. Among six bacteria, Pseudomonas aeruginosa, Aggregatibacter actinomycetemcomitans, and Aeromonas hydrophila induced a potent gut-barrier interruption. Next, the recovering effect of natural products against those pathogens was investigated. As a result, schisandrin C was an effective natural compound that ameliorated the gut permeability dysfunction caused by three pathogenic bacteria and red yeast rice ethanol had a mild protective effect as it only restored the impaired gut barrier caused by the supernatant of P. aeruginosa.
more목차 도움말
CONTENTS I
LIST OF FIGURES III
ABBREVIATIONS AND SYMBOLS IV
ABSTRACT 1
국 문 초 록 3
1. INTRODUCTION 5
1.1. Overview of inflammatory bowel disease 5
1.2. Overview of Caenorhabditis elegans 7
1.3. Overview of pathogenic bacteria 11
1.4. Overview of natural products 13
1.5. Objectives 17
2. MATERIAL AND METHODS 18
2.1. Materials 18
2.2 C. elegans maintenance 19
2.3 Bacterial culture condition 19
2.4 Toxicity evaluation of different pathogenic bacteria on the growth of C. elegans 20
2.5 Toxicity evaluation of different natural products on the growth of C. elegans 21
2.6 The measurement of FITC-dextran permeability in worms fed with different pathogenic bacteria and natural products. 21
2.6.1 Screening pathogenic bacteria for inducing gut permeability dysfunction in C. elegans. 21
2.6.2. Checking the effect of live and heat-inactivated bacteria and supernatant of pathogenic bacteria on the intestinal permeability of C. elegans. 22
2.6.3 Screening of natural products against gut permeability dysfunction induced by pathogenic bacteria. 22
3. RESULTS 24
3.1. The toxic effect of different pathogenic bacteria on the growth of C. elegans 24
3.2. The effect of natural products on the growth of C. elegans. 27
3.3. The effect of different pathogenic bacteria on intestinal permeability of C. elegans. 30
3.4. The effect of bacteria and supernatant of A. actinomycetemcomitans, A. hydrophila, and P. aeruginosa on the intestinal permeability of C. elegans 34
3.5. The effect of live and heat-inactivated bacteria and supernatant of A. actinomycetemcomitans, A. hydrophila, and P. aeruginosa on the intestinal permeability of C. elegans. 37
3.6. Screening of natural products against intestinal permeability dysfunction induced by pathogenic bacteria. 41
3.7. The effect of natural product on the intestinal permeability of C. elegans infected by A. actinomycetemcomitans. 41
3.8. The effect of natural product on the intestinal permeability of C. elegans infected by A. hydrophila. 45
3.9. The effect of natural product on the intestinal permeability of C. elegans infected by P. aeruginosa 48
3.10. The effect of natural product on the intestinal permeability of C. elegans treated with the supernatant of A. hydrophila. 51
3.11. The effect of natural product on the intestinal permeability of C. elegans treated with the supernatant of P. aeruginosa. 54
4. DISCUSSION 57
5. REFERENCES 61
