Irisin is a myokine that stimulates browning of white adipocytes and enhances cortical bone mass during physical exercise. However, its short half-life limits its therapeutic potential, making sustained delivery systems desirable for bone tissue regeneration. In this study, we evaluated the effect of irisin-loaded porous silica nanoparticles (SiNPs) on caudal fin regeneration in a cholesterol-rich diet-induced obese medaka fish model, compared with irisin alone. Obese medaka were generated by feeding a 20% cholesterol diet for 2 months, followed by caudal fin amputation. Irisin formulations (free irisin or SiNP-loaded irisin at 350 ng and 700 ng) were administered via intraperitoneal injection. Cholesterol-fed medaka showed significant weight gain and fat accumulation over 30 days. Following fin amputation, bone regeneration was impaired in obese fish compared to normal controls. Notably, irisin-loaded SiNPs significantly enhanced fin regeneration, particularly at the higher dose (700 ng), compared to free irisin. These findings demonstrate that irisin delivered in porous silica nanoparticles improves bone regeneration in an obese medaka fish model more effectively than irisin alone.
Sadanandan et al. (Sat,) studied this question.