The Expression and Role of Hypoxia-induced Factor-1α in Human Tenon's Capsule Fibroblasts under Hypoxia.

PURPOSE: To determine the expression of hypoxia-induced factor-1α (HIF-1α) and its downstream factors in human Tenon's capsule fibroblasts (HTFs) and changes in HTFs biological functions, we explored the role of HIF-1α in HTFs under hypoxia to provide a basis for studying the regulation of HIF-1α in wound healing after glaucoma surgery. MATERIALS AND METHODS: we established HTFs hypoxia model in vitro, meanwhile the HIF-1α agonist VH298 or inhibitor KC7F2 was added to HTFs, and the normoxia group was used as a control. Western blot, immunofluorescence and ELISA were used to detect the expression of HIF-1α, vascular endothelial growth factor (VEGF), transforming growth factor-ß (TGF-ß), Smads and collagen I. The proliferation of HTFs was quantified by cell counting kit-8, and cell migration was tested by healing scratch test. RESULTS: HIF-1α protein expression increased under hypoxia, peaked from 4-24 h, and then decreased. The secretion of VEGF and TGF-ß increased with prolonged hypoxia time. VH298 and KC7F2 upregulated and downregulated the levels of VEGF and TGF-ß, respectively, suggesting that HIF-1α upregulates and downregulates the levels of VEGF and TGF-ß in HTFs under hypoxia, respectively. HIF-1α upregulated the proliferation, migration and collagen synthesis of HTFs under hypoxia. CONCLUSIONS: Regulating HIF-1α and its downstream factors effectively regulated HTFs proliferation, migration and collagen synthesis. HIF-1α is a promising regulator in the study of wound healing after glaucoma surgery.

A Comparison of Subconjunctival Wound Healing between Different Methods of Dissecting Subconjunctival Tissues.

OBJECTIVE: To compare different methods for dissecting subconjunctival tissues by developing subconjunctival wound healing models. METHODS: New Zealand white rabbits were separated into 3 groups based on the method by which the rabbit subconjunctival wound healing model was generated: subconjunctival tissues were dissected episclerally (EPI) or subepithelially (SUB), with a corresponding blank control (CON). All the cases in the experimental groups were surgically prepared with conjunctival flaps, and they were sacrificed on the third postoperative day. At the surgical sites, the protein levels of hypoxia-inducible factor-1 (HIF-1)-α, vascular endothelial growth factor (VEGF)-A, and matrix metalloproteinase (MMP)-2 were detected by Western blot, morphological vascularity was measured by Adobe Photoshop, and subconjunctival fibrosis was assessed by histology. RESULTS: Compared with the CON group, both the EPI and SUB groups showed significantly upregulated protein levels of HIF-1α, VEGF-A, and MMP-2. In addition, the protein levels of HIF-1α, VEGF-A, and MMP-2 were higher in the EPI group than in the SUB group. Morphological vascularity was significantly elevated in the EPI group compared with the SUB and CON groups. Collagen content was markedly increased in the EPI group compared with the SUB and CON groups. CONCLUSIONS: Dissecting subconjunctival tissues subepithelially inhibits subconjunctival fibrosis, which may be instructive in tenonectomy in filtration surgery.

One-month IOP in mitomycin C-augmented trabeculectomy can predict long-term IOP control in chronic primary angle-closure glaucoma.

PURPOSE: To investigate the predictors of long-term intraocular pressure (IOP) in chronic primary angle-closure glaucoma (CPACG) treated with primary trabeculectomy. METHODS: This study systematically reviewed cases of CPACG treated with primary trabeculectomy. The scleral flaps in all cases were sutured with two stitches in situ and two releasable sutures to ensure watertight under normal IOP conditions during surgery. Mitomycin C was used in all eyes. All patients were followed for 2 years. Digital massage of the bulbus and removal of the releasable suture were performed according to the IOP and shape of the filtering bleb. Demographic data and clinical outcomes were recorded. Factors predicting long-term IOP were identified. RESULTS: A total of 72 patients (88 eyes) with a mean age of 58.51 ± 10.60 years were included in this study. The complete success rate was 89.77% after 2 years. The IOP began to stabilize after 7 days and reached its lowest point at the 1-month follow-up. The preoperative and early postoperative high or low IOP does not affect long-term effects (P > 0.05). There was a positive correlation between postoperative IOP at the 1-month and 2-year follow-ups (r = 0.64, P < 0.001). CONCLUSION: In CPACG patients undergoing primary trabeculectomy, scleral flaps sutured watertightly with two stitches in situ and two releasable sutures under normal IOP conditions can ensure controllable, effective and safe treatment of CPACG. The preoperative and early postoperative high or low IOP does not affect long-term effects. One-month postoperative IOP can be used as a predictor of long-term IOP control.