Hypericin과 광처리가 예쁜꼬마선충에 미치는 영향 연구
INVESTIGATING THE EFFECTS OF HYPERICIN AND LIGHT TO Caenorhabditis elegans
- 주제(키워드) 도움말 hypericin , Caenorhabditis elegans , photodynamic therapy , reactive oxygen species (ROS) , orange light , ultra violet (UV)
- 발행기관 강릉원주대학교 일반대학원
- 발행년도 2019
- 학위수여년월 2019. 8
- 학위명 석사
- 학과 및 전공 도움말 일반대학원 KIST강릉분원학.연협동과정
- 실제URI http://www.dcollection.net/handler/kangnung/000000010528
- UCI I804:42001-000000010528
- 본문언어 영어
초록/요약 도움말
Hypericin is a natural product isolated from Saint John’s wort, Hypericum perforatum and widely used as a typical photosensitizer in cancer photodynamic therapy (PDT). During the illumination with appropriate wavelength, hypericin is activated and generates subsequent cytotoxic products such as free radicals and singlet oxygen which are known as reactive oxygen species (ROS). In this study, we investigate the effect of hypericin and light treatment on the physiology, longevity and stress resistance of Caenorhabditis elegans (C. elegans), a model nematode. The high concentration of hypericin (500 and 1000 µM) decreased the body length, body bending activity, and the number of egg laid, while 20 µM hypericin had no significant toxicity in C. elegans. We also determined the toxic range of UV (320 - 400 nm) and orange light (590 nm) in C. elegans based on the observation of the growth and behavior of worms. Through the investigation of a wide range of intensity, exposure time, and treatment interval of light, we finally optimized hypericin and orange light treatment condition for promoting the health condition in C. elegans. Proper amount of hypericin and orange light co-treatment showed a significant increase of the body size and body bending frequency as well as lifespan of C. elegans as compared to those of the control worms. Besides, the PDT-treated worms subsequently showed the resistance to rotenone stress and the significant longer lifespan compared to the control worms. These data suggest that the biophotonic reaction between hypericin and orange light generates a proper amount of ROS, as a result, it enhances the adaptive responses and extends the lifespan of C. elegans
more목차 도움말
LIST OF FIGURES iii
LIST OF TABLES v
ABBREVIATIONS AND SYMBOLS vi
ABSTRACT viii
1. INTRODUCTION 1
1.1. Overview about Caenorhabditis elegans 1
1.2. Characteristics of light 3
1.3. Photodynamic therapy (PDT) 5
1.3.1. Definition 5
1.3.2. Advantages and disadvantages 5
1.3.3. Principles 6
1.4. Hypericin 6
1.4.1. Name and structure. 6
1.4.2. Chemical and physical properties 7
1.4.3. Hypericin-PDT principles 7
1.5. Reactive oxygen species (ROS) 9
1.5.1. Definition and principles 9
1.5.2. Free radical theory of aging 9
1.5.3. The hormesis theory 10
1.6. Objectives 11
2. MATERIALS AND METHODS 12
2.1. Materials 12
2.2. Methods 12
2.2.1. Compound treatment 12
2.2.2. Preparation of resuspended E. coli OP50 culture 14
2.2.3. Light experiments 15
2.2.4. The measurement of body length 15
2.2.5. Egg laying assay 15
2.2.6. Body bending measurement 15
2.2.7. Lifespan assay. 17
2.2.8. Stress resistant assay 17
2.2.9. Statistical analysis 18
3. RESULTS AND DISCUSSION 19
3.1. The effect of hypericin on the development, reproduction and exercise activity of C. elegans 19
3.1.1. Experimental design 19
3.1.2. Growth curve 21
3.1.3. Body bending 23
3.1.4. Egg laying assay 25
3.2. The effect of PDT with different light intensities and exposure time points 27
3.2.1. The experimental design 27
3.2.2. Effect of orange light (5.4 W/m2) 29
3.2.3. Effect of orange light (36.7 W/m2) 33
3.2.4. Orange light (108.4 W/m2) 37
3.2.5. UVA (6.5 W/m2) 41
3.3. The effect of different PDT treatment duration to the lifespan of C. elegans 46
3.3.1. Experimental design 46
3.3.2. 10-day treatment duration 48
3.3.3. 5-day treatment duration 51
3.4. PDT induces the stress resistance in C. elegans 55
3.4.1. Experimental design 55
3.4.2. The body bending of C. elegans after different treatment duration 57
3.4.3. Rotenone resistance 59
3.4.4. Heat shock 62
4. CONCLUSIONS 64
5. REFERENCES 67
6. ACKNOWLEDGEMENT 72
