[The trabecular meshwork: Structure, function and clinical implications. A review of the littérature (French translation of the article)]

Genistein stimulates the viability and prevents myofibroblastic transformation in human trabecular meshwork cells stimulated by TGF-β

Primary open-angle glaucoma (POAG) is the most common type of glaucoma leading to blindness. The search for ways to prevent/treat this entity is one of the main challenges of today's ophthalmology. One of such solution seems to be biologically active substances of natural origin, such as genistein (GEN), which can affect the function of isolated trabecular meshwork by the inhibition of protein tyrosine kinase. However, the role of GEN in viability as well as myofibroblastic transformation in human trabecular meshwork cells stimulated by TGF-β is unknown. Using human trabecular meshwork cells (HTMCs) we investigated the effect of genistein on cell viability and myofibroblastic transformation stimulated by TGF-β1 and TGF-β2. Using Real-Time PCR, western blot and immunofluorescence we determined the effect on the expression changes of αSMA, TIMP1, collagen 1 and 3 at mRNA and protein level. We found that genistein increases the viability of HTMCs (1, 2, 3 μg/ml; P < 0.05 and 4, 5, 10, 15, 20 μg/ml; P < 0.01). Moreover, we found that addition of 10, 15 and 20 μg/ml is able to prevent myofibroblastic transformation of HTMCs by decreasing αSMA, TIMP1, collagen 1 and 3 mRNA and protein expression (P < 0.01). Based on the obtained results, we can conclude that genistein is a potential factor that can prevent the myofibroblastic transformation of HTMCs accompanying glaucoma. Describing GEN influence on myofibroblastic transformation processes in HTMC allows us to conclude that it can be considered a potential therapeutic agent or a substance supporting treatment in patients with glaucoma.

The ocular anterior segment examination of perinatal newborns by wide-field digital imaging system: a cross-sectional study

PURPOSE

The aim of this study was to evaluate and summarize the developmental rules of the ocular anterior segment of neonates by means of wild-field digital imaging system.

METHODS

We used the wide-field digital imaging system to sequentially capture images of the neonates' eyes within 42 days after delivery, including the ocular surface, anterior segment, and fundus. At the same time, basic information at the time of birth and examination was collected.

RESULTS

Among 248 newborns, 51.21% were male. Abnormalities of the anterior segment such as visualization of anterior chamber angle vessels (79.03%) and iris vessels (51.21%), iris process (42.34%), persistent pupillary membranes (19.35%), albinism, congenital cataracts, corneal leucoma, and subconjunctival hemorrhage were observed in this study. There were significant differences in the appearance of iris vessels among different sex, gestational age and birth weight, postmenstrual age and weight at the time of examination and iris color groups. The iris vessels were more visualized in males relative to females (OR = 6.313, 95% CI 2.529-15.759). The greater the postmenstrual age at the time of examination, the lower the visualization of iris vessels (OR = 0.377, 95% CI 0.247-0.575). In addition, although visualization of anterior chamber angle vessels differed within the birth gestation age and weight at examination groups, there was no significant correlation by regression analysis.

CONCLUSIONS

The anterior segment of perinatal neonates can be visualized by the wide-field digital imaging system. The neonatal iris and anterior chamber angle are immature, and the visible vessels at the anterior chamber angle that vanish later than the surface of the iris are characteristic structures.

ALK5 inhibitor acts on trabecular meshwork cell and reduces intraocular pressure

Intraocular pressure (IOP) is the most important risk factor for the onset and progression of glaucoma. IOP reduction has been proven effective in the treatment of glaucoma. IOP is controlled by the production and outflow of the aqueous humor (AH), and the trabecular meshwork (TM) is the main pathway for AH drainage from the eye. However, there are few conventional IOP-lowering treatments that target TM, and there is a need for such treatments. In this study, we screened for the expression level of fibronectin as an indicator and identified an activin receptor-like kinase (ALK) 5 inhibitor. Western blot analysis showed that SB431542, an ALK 5 inhibitor, reduced fibronectin and α-SMA expression. Moreover, a single dose of the ALK5 inhibitor SB431542 reduced IOP in mice, and the IOP-lowering effect of the ALK5 inhibitor was greater than that of a Rho-associated coiled-coil-containing protein kinase inhibitor (Y-27632). Repeated dosing with ALK5 inhibitor eye drops (once daily) enhanced the murine IOP-lowering effect. Furthermore, ALK5 inhibition decreased the expression of extracellular matrix (ECM) mRNA and suppressed ECM production. These findings suggest that ALK5 inhibitors may contribute to the development of new treatments for glaucoma that target the TM.