AIM: To prepare a nanodrug MMC-ATS-@PLGA using polylactic acid hydroxyacetic acid copolymer(PLGA)as a carrier and mitomycin C(MMC)loaded on PLGA, and to analyse the biological safety and treatment effect of this nanodrug on inhibiting the proliferation of filtering bleb scarring after glaucoma surgery in vivo.

METHODS: The thin-film dispersion hydration ultrasonic method was used to prepare the MMC-ATS-@PLGA, and its physical and chemical properties were detected. The effect of MMC-ATS@PLGA on rabbit corneas was analysed through corneal fluorescence staining and HE staining, and tear film rupture time(BUT), Schirmer test and intraocular pressure data were collected to analyse ocular surface biosafety. A slit lamp was used to observe and calculate the filtration bubble size, and the tissue morphological changes were analysed by conjunctival HE staining. In addition, immunohistochemistry and Elisa were used to compare the anti-inflammatory effects of Flumiolone Eye Drops(FML), MMC, and MMC-ATS-@PLGA nanoparticles on inhibiting the formation of filtering bleb scarring after glaucoma surgery from multiple perspectives via comparative proteomic analysis.

RESULTS: The average particle size and zeta potential of MMC-ATS-@PLGA were 128.78±2.54 nm and 36.49±4.25 mV, respectively, with an encapsulation efficiency and a drug loading rate of(78.49±2.75)% and(30.86±1.84)%, respectively. At 33°C(the ocular surface temperature), the cumulative release rate of the MMC-ATS-@PLGA nanoparticles reached(76.58±2.68)% after 600 min. Moreover, corneal fluorescence staining, HE, BUT, Schirmer, and intraocular pressure results showed that MMC-ATS-@PLGA had good biocompatibility with the ocular surface of rabbits. At 3 wk after surgery, the area of filtering blebs in the MMC-ATS-@PLGA group was significantly larger than that in the FML group and MMC group, and the filtering blebs in the control group had basically disappeared. Pathological tissue analysis of the conjunctiva in the filtering blebs area of the eyes of the rabbits revealed that compared with that in the normal group, the morphology of the collagen fibres in the MMC-ATS-@PLGA group was relatively regular, the fibres were arranged neatly, and the tissue morphology was similar to that of the normal group. Immunohistochemistry and Elisa confirmed that compared with those in the normal group, the expression levels of α-SMA, CTGF, and type Ⅲ collagen fibre antibodies were significantly increased in the control group. After FML, MMC, or MMC-ATS-@PLGA treatment for 3 wk, the expression of inflammatory factors gradually decreased. Among the groups, the MMC-ATS-@PLGA group showed the most significant decrease(P<0.05).

CONCLUSION: This study successfully synthesized a nanomedicine(MMC-ATS-@PLGA)that inhibits scar proliferation after glaucoma filtration surgery. The drug had stable physicochemical properties, good biocompatibility, and better anti-inflammatory effects by inhibiting the expression of α-SMA, CTGF, and type Ⅲ collagen fibres, which can prevent the formation of scarring in the filtering blebs area, thereby improving the success rate of glaucoma filtering surgery.