Effect of ß-carotene on the differentiation potential of ciliary epithelium-derived MSCs isolated from mouse eyes on alginate-based scaffolds.

Retinal degenerative diseases are considered a major challenge all over the world, and stem cell therapy is a promising approach to restore degenerative cells due to RD. MSCs are multipotent stem cells found in a variety of tissues. They are capable of differentiating into various retinal cell types, so it can be a good candidate for various degenerative disorders like retinal degenerations. ß-carotene is an antioxidant that could accelerate the stem cell differentiation while using the proper scaffold. In this study, we evaluated the effect of ß-carotene on the differentiation potential of ciliary epithelium-derived MSCs isolated from mouse eyes on alginate-based scaffolds. MSCs were isolated from mouse ciliary epithelium, cultured in DMEM medium supplemented with 10% FBS, and identified by detecting their surface antigens. Three 3D culture systems, alginate, alginate/gelatin, and gelatin hydrogels were prepared, and their structures were checked via SEM. MSCs were cultured on 3D and 2D culture system scaffolds following treated with differentiation medium containing 50 µM ß-mercaptoethanol, 1 × minimum essential medium-nonessential amino acids and 20% of knockout serum replacement and ß-carotene. MSCs viability and differentiation ability were examined by MTT and ICC, respectively. The expression changes of several retinal specific genes (Nestin, RPE65, and Rhodopsin) were also evaluated by qPCR. Over 80% of cells isolated from mouse ciliary epithelium were positive for MSC-specific markers. The viability rates of MSCs grown on all alginate-based scaffolds were above 70%. MSCs cultured on alginate-based scaffold in the differentiation medium containing ß-carotene expressed higher levels of rhodopsin protein compared to a 2D culture. Also, the expressions of Nestin, Rhodopsin, and RPE65 genes were upregulated in ß-carotene-treated MSCs grown on alginate-based scaffolds. Our results indicate that the addition of ß-carotene to the differentiation medium, along with applying alginate-based scaffolds, could induce higher differentiation in mouse ciliary epithelium-derived MSCs into specialized retinal cells.

Comparison of Refractive Error Changes in Retinopathy of Prematurity Patients Treated with Diode and Red Lasers.

AIM: To compare refractive error changes in retinopathy of prematurity (ROP) patients treated with diode and red lasers. METHODS: A randomized double-masked clinical trial was performed, and infants with threshold or prethreshold type 1 ROP were assigned to red or diode laser groups. Gestational age, birth weight, pretreatment cycloplegic refraction, time of treatment, disease stage, zone and disease severity were recorded. Patients received either red or diode laser treatment and were regularly followed up for retina assessment and refraction. The information at month 12 of corrected age was considered for comparison. RESULTS: One hundred and fifty eyes of 75 infants were enrolled in the study. Seventy-four eyes received diode and 76 red laser therapy. The mean gestational age and birth weight of the infants were 28.6 ± 3.2 weeks and 1,441 ± 491 g, respectively. The mean baseline refractive error was +2.3 ± 1.7 dpt. Posttreatment refraction showed a significant myopic shift (mean 2.6 ± 2.0 dpt) with significant difference between the two groups (p < 0.001). There was a greater myopic shift among children with zone I and diode laser treatment (mean 6.00 dpt) and a lesser shift among children with zone II and red laser treatment (mean 1.12 dpt). The linear regression model, using the generalized estimating equation method, showed that the type of laser used has a significant effect on myopic shift even after adjustment for other variables. CONCLUSION: Myopic shift in laser-treated ROP patients is related to the type of laser used and the involved zone. Red laser seems to cause less myopic shift than diode laser, and those with zone I involvement have a greater myopic shift than those with ROP in zone II.

Intrasubject Difference in CCT among POAG versus Normal Individuals.

PURPOSE: To evaluate intrasubject asymmetry in central corneal thickness (CCT) among patients with primary open-angle glaucoma (POAG) as compared with that of normal subjects and to determine whether the eye with thinner cornea has more severe glaucomatous visual field damage. METHODS: In this case-control study, CCT of both eyes was measured using an ultrasonic pachymeter (UP-1000; Nidek Technologies, Gamagori, Japan) among POAG patients and normal subjects. The intrasubject difference in CCT was calculated and compared between the study groups; correlations between CCT and intraocular pressure (IOP), vertical cup-to-disc ratio (VCDR), and visual field defects were also evaluated. RESULTS: A total of 62 patients with bilateral POAG and 56 normal subjects were included. There was no significant difference between the study groups in terms of age, sex, and ocular parameters except for visual acuity, IOP, and VCDR. The POAG patients demonstrated significantly greater intrasubject asymmetry in CCT (8 ± 7 µm vs. 5 ± 3 µm; p = 0.041) and a higher prevalence of significant (>10 µm) intrasubject CCT difference (30.6 vs. 5.4%; p < 0.001) as compared with normal subjects. Although each higher level of glaucomatous damage was associated with 4-µm thinner CCT, the correlation was not statistically significant (95% confidence interval, -8 to 1 µm; p = 0.117; GEE analysis). No significant correlation was observed between CCT and IOP or VCDR (p = 0.302 and 0.137, respectively). CONCLUSIONS: Patients with POAG demonstrate a larger amount of intrasubject difference in CCT as compared with normal subjects.

Evaluation of the Potential Effects of Retinol and Alginate/Gelatin-Based Scaffolds on Differentiation Capacity of Mouse Mesenchymal Stem Cells (MSCs) into Retinal Cells.

Background and Objectives: Retinal stem cells (RSCs) resided in ciliary epithelium have shown to possess a high capacity to self-renew and differentiate into retinal cells. RSCs could be induced to differentiate when they are exposed to stimuli like natural compounds and suitable contexts such as biomaterials. The aim of this study was to examine the effects of Retinol and alginate/gelatin-based scaffolds on differentiation potential of mesenchymal stem cells (MSCs) originated from mouse ciliary epithelium. Methods and Results: MSCs were extracted from mouse ciliary epithelium, and their identity was verified by detecting specific surface antigens. To provide a three-dimensional in vitro culture system, 2% alginate, 0.5% gelatin and the mixed alginate-gelatin hydrogels were fabricated and checked by SEM. Retinol treatment was performed on MSCs expanded on alginate/gelatin hydrogels and the survival rate and the ability of MSCs to differentiate were examined through measuring expression alterations of retina-specific genes by ICC and qPCR. The cell population isolated from ciliary epithelium contained more than 93.4% cells positive for MSC-specific marker CD105. Alginate/gelatin scaffolds showed to provide an acceptable viability (over 70%) for MSC cultures. Retinol treatment could induce a high expression of rhodopsin protein in MSCs expanded in alginate and alginate-gelatin mixtures. An elevated presentation of Nestin, RPE65 and Rhodopsin genes was detected in retinol-treated cultures expanded on alginate and alginate-gelatin scaffolds. Conclusions: The results presented here elucidate that retinol treatment of MSCs grown on alginate scaffolds would promote the mouse ciliary epithelium-derived MSCs to differentiate towards retinal neurons.