title: Biomechanics of sclera crosslinked using genipin in rabbit.
abstract: OBJECTIVE
  To strengthen the biomechanics of collagen by crosslinking rabbit scleral collagen with genipin to develop a new therapy for preventing myopic progression.
  
  
  METHODS
  Ten New Zealand rabbits were treated with 0.5 mmol/L genipin injected into the sub-Tenon's capsule in the right eyes. Untreated contralateral eyes served as the control. The treated area was cut into scleral strips measuring 4.0 mm×10.0 mm for stress-strain measurements (n=5). The remaining five treated eyes were prepared for histological examination.
  
  
  RESULTS
  Compared to the untreated scleral strips, the genipin-crosslinked scleral strips showed that the ultimate stress and Young's modulus at 10% strain were increased by the amplitude of 130% and 303% respectively, ultimate strain was decreased by 24%. There had no α-smooth muscle actin (α-SMA) positive cells in control and treated sclera. Histologically, there was no sign of apoptosis in the sclera, choroid, and retina; and no side effects were found in the peripheral cornea and optic nerve adjacent to the treatment area.
  
  
  CONCLUSIONS
  Genipin induced crosslinking of collagen can increase its biomechanical behavior by direct strengthening of the extracellular matrix in rabbit sclera, with no α-SMA expression seen in the myofibroblasts. As there is no evidence of cytotoxicity in the scleral, choroidal, and retinal cells, genipin is likely a promising agent to strengthen the weakened sclera to prevent myopic progression.
authors.affiliation: Guizhou Ophthalmic Hospital, Affiliated Hospital of Zunyi Medical College, Zunyi 563003, Guizhou Province, China.
authors.forename: Tai-Xiang
authors.initials: TX
authors.lastname: Liu
authors.affiliation: Zhongshan Ophthalmic Center of Sun Yat-sen University, the State Key Laboratory of Ophthalmology, Guangzhou 510060, Guangdong Province, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
keywords: biomechanics; crosslinking; genipin; myopia; sclera