Possibility of nanostructured lipid carriers encapsulating astaxanthin from Haematococcus pluvialis to alleviate skin injury in radiotherapy

AbstractPurpose The study aimed to protect patients’ skin against ionizing irradiation during radiotherapy by using astaxanthin-encapsulated nanostructured lipid carriers (NLC-ATX).Materials and methods NLC-ATX was prepared by a combined method of hot homogenization and sonication. Cytotoxicity of NLC-ATX was evaluated by MTT colorimetric assay. The in vitro radioprotection of NLC-ATX for human fibroblast (HF) cells was investigated based on the level of ROS (reactive oxygen species), DNA damage, and cell death caused by X-irradiation. In addition, the in vivo radioprotection was evaluated based on the appearance and histological structure of the irradiated skin.Results NLC-ATX was successfully prepared, with a mean particle size, zeta potential, and encapsulation efficiency of 114.4 nm, −34.1 mV, and 85.67%, respectively. Compared to the control, NLC-ATX, at an optimum ATX concentration under in vitro condition, reduced the amount of generated ROS and DNA damage of 81.6% and 41.6%, respectively, after X-radiation, resulting in a significant decrease in cell death by 62.69%. Under in vivo condition, after the 9th day of X-irradiation (equivalent to an accumulated dose of 14 Gy), the dorsal skin of five out of six NLC-ATX-untreated mice exhibited grade-1 skin damage, according to CTCAE v5.0, while treatment with NLC-ATX protected 6/6 mice from acute skin damage. Moreover, on the 28th day after the first X-irradiation, the histological images illustrated that NLC-ATX at an ATX concentration of 0.25 µg/mL exhibited good recovery of the skin, with barely any difference noted in the collagen fibers and sebaceous glands compared to normal skin.Conclusions NLC-ATX shows potential for application in skin protection against adverse effects of ionizing rays during radiotherapy.Keywords: Astaxanthinhuman fibroblastsionizing radiationnanoparticlesnanostructured lipid carrier AcknowledgementsThe authors would like to thank the Nuclear Research Institute for creating favorable conditions during the implementation of this research.Disclosure statementThe authors report there are no competing interests to declare.Additional informationFundingThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.Notes on contributorsNgoc-Bich-Dao VuNgoc-Bich-Dao Vu, MSc, is a researcher at Center of Radiation Technology and Biotechnology, Nuclear Research Institute, Vietnam, a PhD student at the Department of Biochemistry, Faculty of Biology Biotechnology, University of Science, Vietnam National University, Ho Chi Minh City, Vietnam.Ngoc-Duy PhamNgoc-Duy Pham, MSc, is a researcher at Center of Radiation Technology and Biotechnology, Nuclear Research Institute, Vietnam.Thi-Ngoc-Mai TranThi-Ngoc-Mai Tran, MSc, is a researcher at Center of Radiation Technology and Biotechnology, Nuclear Research Institute, Vietnam.Xuan-Hai PhamXuan-Hai Pham, MSc, is a researcher at Training Center, Nuclear Research Institute, Vietnam.Dai-Nghiep NgoDai-Nghiep Ngo, Prof. PhD, is a main lecturer at the Department of Biochemistry, Faculty of Biology Biotechnology, University of Science, Ho Chi Minh City, Vietnam.Minh-Hiep NguyenMinh-Hiep Nguyen, PhD, is a main researcher, Director of the Center of Radiation Technology and Biotechnology, Nuclear Research Institute, Vietnam.