Light-triggered methylcellulose gold nanoparticle hydrogels for leptin release to inhibit fat stores in adipocytes

Zi-Xian Liao,1 Meng-Chia Liu,1 Ivan M Kempson,2 Yu-Chen Fa,1 Kuo-Yen Huang3,4 1Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan; 2Future Industries Institute, University of South Australia, Mawson Lakes, SA, Australia; 3Institute of Biomedical Sciences, Academia Sinica, Taipei, 4Graduate Institute of Health Industry Technology and Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan Abstract: Leptin is released in response to increased triglyceride storage in adipocytes and impacts body weight, but has drawbacks such as poor therapeutic effect and side effects when delivered systemically. Leptin also modifies adipocyte sensitivity to insulin to inhibit lipid accumulation. Here, light-triggered degradation of hydrogels was used to improve accuracy and effectiveness for sustained and controllable release. In our approach, leptin was entrapped within methylcellulose (MC)-based hydrogels, with incorporation of gold nanoparticles (NP). The incorporation of gold NP into MC hydrogels led to a tunable light irradiation response that dictated the hydrogel release rate of leptin. This manuscript demonstrates feasibility in designing tunable thermosensitive hydrogels for loading multimodality therapeutic agents to enhance the bioactivity of leptin for obesity therapy. Keywords: leptin, adipocytes differentiation, methylcellulose, gold nanoparticle, degradable hydroge