Use of 5-Fluorouracil-Soaked Bioamniotic Membranes in Trabeculectomy for Primary Open-Angle Glaucoma: A Retrospective Analysis

Chitosan modified 5-fluorouracil nanostructured lipid carriers for treatment of diabetic retinopathy in rats: A new dimension to an anticancer drug

Diabetic retinopathy (DR) is one of the chronic complications of diabetes. It includes retinal blood vessels' damage. If untreated, it leads to loss of vision. The existing treatment strategies for DR are expensive, invasive, and need expertise during administration. Hence, there is a need to develop a non-invasive topical formulation that can penetrate deep to the posterior segment of retina and treat the damaged retinal vessels. In addition, it should also provide sustained release. In recent years, novel drug delivery systems (NDDS) have been explored for treating DR and found successful. In this study, chitosan (CS) modified 5-Fluorouracil Nanostructured Lipid Carriers (CS-5-FU-NLCs) were prepared by modified melt emulsification-ultrasonication method and optimized by Box-Behnken Design. The size, polydispersity index, zeta potential and entrapment efficiency of CS-5-FU-NLCs were 163.2 ± 2.3 nm, 0.28 ± 1.52, 21.4 ± 0.5 mV and 85.0 ± 0.2 %, respectively. The in vitro drug release and ex vivo permeation study confirmed higher and sustained drug release in CS-5-FU-NLCs as compared to 5-FU solution. HET-CAM Model ensured the non-irritant nature of CS-5-FU-NLCs. In vivo ocular studies of CS-5-FU-NLCs confirmed antiangiogenic effect of 5-FU by CAM model and diabetic retinopathy induced rat model, indicating successful delivery of 5-FU to the retina.

Effectiveness and Safety of Trabeculectomy along with Amniotic Membrane Transplantation on Glaucoma: A Systematic Review

Purpose

To determine the effectiveness and safety of trabeculectomy along with amniotic membrane transplantation (AMT) for glaucoma.

Methods

This systematic review was performed using RevMan 5.3. We searched PubMed, EMBASE, and the Cochrane Library and included studies published until September 2019. The treatment group included patients with AMT and trabeculectomy (group A), and the control group had only trabeculectomy (group B). We only included randomized controlled trials. The outcomes were intraocular pressure (IOP), complete success rate, number of antiglaucoma medications, and complications.

Results

Five studies, including 174 eyes (87 eyes in the AMT group and 87 eyes in the control group), were eligible in this review. The parameters had no significant difference in heterogeneity between the AMT and control groups preoperatively. In the AMT group, the mean IOP was significantly lower at 3 and 12 months after operation (P < 0.0001 and P = 0.02, respectively), while the number of complete successes in the AMT group was significantly higher at 6 and 12 months (P = 0.02 and P = 0.003, respectively) compared with the control group. Complications, including a flat anterior chamber and hyphema, appeared to be decreased in the AMT group compared to the control group (P = 0.02 and P = 0.02, respectively). No differences were observed in the number of antiglaucoma medications, hypotony, encapsulated bleb, or choroidal detachment.

Conclusion

Compared with only trabeculectomy, it is more efficient and safer to add AMT to trabeculectomy during glaucoma filtering surgery.

[Anti-scarring effect of rapamycin following filtering surgery in rabbit eyes]

OBJECTIVE

To study the effect of rapamycin on scar formation in rabbit eyes following filtering operation and explore the possible mechanism.

METHODS

Ninety-six healthy adult rabbits were subjected to trabeculectomy of the left eye and subsequently randomly divided into 4 groups (n=24) for treatment with castor oil (control) or rapamycin (1%, 3%, or 5%) eye drops of the operated eyes 4 times a day. The morphology and function of the filtering blebs of the rabbits were compared at 7, 14, 21 and 28 days after the operation; at each of the time points, 6 rabbits from each group were euthanized for detection of expressions of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA) in the tissues in the surgical area using immunohistochemistry. Cultured rabbit subconjunctival fibroblasts (RTFSs) were treated with different concentrations of rapamycin (0.06, 0.25, 1, and 4 mg/L) and the cell apoptosis was detected using flow cytometry.

RESULTS

In the first, second and third weeks after the operation, the rate of functional follicle formation was significantly higher in the 3 rapamycin groups than in the control group (P < 0.05), and the number of α- SMA-positive fibroblasts decreased over time in the 3 rapamycin groups. In cultured RTFSs, treatment with rapamycin at different concentrations resulted in increased apoptosis of the cells, and rapamycin above 0.25 mg/L significantly increased the cell apoptosis in a dose-dependent manner.

CONCLUSIONS

Rapamycin can inhibit hyperplasia of the filtering passage tissue, helps to preserve the functional filtering blebs and prolong their life span, and induces apoptosis of RTFS.