CD44 Drives M1 Macrophage Polarization in Diabetic Retinopathy.

PURPOSE: Diabetic retinopathy is a typical complication of diabetes, which can facilitate the risk of blindness in severe cases. We sought to determine the function of CD44 in inflammatory responses of human retinal microvascular endothelial cells (HRMECs) and macrophage polarization during diabetic retinopathy (DR). METHODS: The hub genes were tested based on two datasets from the Gene Expression Omnibus database. Gene Ontology and pathway enrichment analysis was conducted on the base of differentially expressed genes (DEGs). The infiltration score and infiltration of the immune cells were assessed, and the link between key genes and macrophages was analyzed. The role of CD44 in HRMECs and macrophage polarization was determined by quantitative reverse transcription polymerase chain reaction, western blot, cell counting kit-8, Enzyme-linked immunosorbent assay, flow cytometry, and immunofluorescence. RESULTS: DEGs were enriched in several pathways linked to DR, such as cellular response to retinoic acid, retinol metabolic process, retina homeostasis, PI3K-AKT signaling pathway, and leukocyte transendothelial migration. A total of 144 DEGs were identified by up-regulation both in GSE102485 and GSE160306. Moreover, the infiltration of macrophages was greater in the DR group than that in the control group. We highlighted an obvious increase in the expression of CD44 and CD86 in patients with DR, and distinct positive associations were found between levels of macrophages and levels of CD44 and CD86. Furthermore, CD44 expression was substantially increased in HRMECs under high glucose (HG) conditions and CD44 knockdown markedly inhibited HG-induced inflammatory responses of HRMECs. HG-induced HRMECs remarkably influenced M1 polarization of macrophages, but CD44 knockdown significantly nullified this effect. CONCLUSIONS: CD44 influenced the advancement of DR via meditating M1 polarization of macrophages. Our findings could enhance the understanding of the mechanism of DR, which might offer a therapeutic target for DR patients.

Downregulation of c-Myc in pterygium and cultured pterygial cells.

BACKGROUND: The aim of this study was to determine c-Myc expression in pterygial tissue and in cultured fibroblasts and epithelial cells of pterygia, using normal human conjunctival samples as a control. METHODS: Expression of c-Myc in pterygium and normal human conjunctiva tissue was examined by immunohistochemical assay and Western blot. Fibroblasts and epithelial cells from primary pterygium and normal human conjunctiva were cultured in medium with or without transforming growth factor beta1 for up to 3 days. c-Myc protein expression was analysed by indirect immunofluorescence. Levels of c-Myc mRNA in fibroblasts were measured by reverse transcription polymerase chain reaction. RESULTS: c-Myc protein expression was reduced in human pterygial tissue compared with normal human conjunctiva in immunohistochemical staining. The decrease was further verified by Western blot analysis. In primary cultured cells c-Myc expression as stained by immunofluorescence was reduced in both pterygial epithelial and fibroblast cells when compared with cultured normal human conjunctiva cells. In addition, compared with cells from normal conjunctiva, reduced levels of c-Myc mRNA were observed in both cultured pterygial epithelial and fibroblast cells. Increased c-Myc expression in pterygial cells, but not in normal conjunctival cells, was found when the cultured cells were treated with transforming growth factor beta1. This increase of c-Myc mRNA appeared to be time and transforming growth factor beta1 dose dependent. CONCLUSIONS: c-Myc expression is reduced in pterygium compared with normal conjunctiva. Transforming growth factor beta1 can elevate the downregulated c-Myc in cultured pterygial cells.

HSV-1 infection suppresses TGF-beta1 and SMAD3 expression in human corneal epithelial cells.

PURPOSE: The present study was undertaken to investigate whether transforming growth factor-beta (TGF-beta) isoforms (TGF-beta1, TGF-beta2, and TGF-beta3) and SMADs (SMAD2 and SMAD3) are involved in herpes simplex virus type 1 (HSV-1) corneal infection. METHODS: Human corneal epithelial cells (HCE) were infected with HSV-1 at a multiplicity of infection of 5. Cell morphological changes were observed under phase-contrast microscopy. Levels of mRNA for TGF-beta isoforms 1, 2, and 3 as well as for SMAD2 and SMAD3 were measured by reverse transcription polymerase chain reaction (RT-PCR) at 0 h, 4 h, 8 h, 12 h, and 24 h after infection. Protein expression of TGF-beta1, TGF-beta2, SMAD3, and phospho-SMAD3 were analyzed by indirect immunofluorescence at 0 h, 12 h, and 24 h post-infection (p.i.) in HCE cells. Protein expression of TGF-beta1 was also evaluated by ELISA. RESULTS: Following HSV-1 infection, a cytopathic effect in HCE cells was observed at 8 h p.i. and became significant at 24 h p.i. Compared with normal cells, the mRNA levels of TGF-beta1 in HSV-1 infected HCE cells decreased significantly at 8 h, 12 h, and 24 h p.i. (p<0.01), and the expression of SMAD3 was also dramatically decreased 12 h and 24 h p.i. (p<0.01). No noticeable changes were found as a result of infection with respect to levels of TGF-beta2, TGF-beta3, and SMAD2 in HCE cells. Protein expression of TGF-beta1, SMAD3, and phospho-SMAD3 decreased in infected cells at 12 h and 24 h p.i. compared with normal cells, but TGF-beta2 had no change. CONCLUSIONS: TGF-beta1 and SMAD3 may be involved in the pathology of corneal diseases associated with HSV-1 infection.

[Analysis of fund sponsored articles from five ophthalmologic journals in 2005].

OBJECTIVE: To reveal the features of fund sponsored articles and the status of scientific research by analyzing fund sponsored articles from 5 ophthalmologic journals in Chinese. METHODS: Five ophthalmologic journals (Chinese Journal of Ophthalmology, Chinese Journal of Ocular Trauma and Occupational Eye Disease with Ophthalmic Surgery, Chinese Ophthalmic Research, Chinese Journal of Practical Ophthalmology, Chinese Journal Ocular Fundus Disease) published in Chinese in 2005 were selected for this study. The amount, the distribution of region, the number of co-authors, the research direction, the number of funds obtained by each paper and the distribution of subjects in various research fields of fund sponsored articles were calculated by quantitative analysis methods. RESULTS: Among 1745 articles published in 2005, 222 were supported by various funds (12.72%). Articles sponsored by national, province/ministry and other sources accounted for 4.70%, 4.81% and 3.21% of all articles, respectively. The highest numbers of co-authors was 5.21. The top region of authors was located in Guangdong Province, which published 71 over 222 papers (31.98%). One hundred and forty nine papers (67.12%) were sponsored by single fund. The subject of fund sponsored articles were mainly in the field of retina (22.97%, 51/222), cornea (17.12%, 38/222) and lens (11.26%, 25/222). CONCLUSIONS: The quantity and the level of fund sponsored articles had been improved greatly in ophthalmology journals. However, this is still inferior to other bio-scientific journals. The whole academic level of ophthalmology journals should be further promoted.

Continuously changed genes during postnatal periods in rat visual cortex.

The current study aimed to determine genes that changed continuously throughout the postnatal developmental process of the rat visual cortex. Tissue samples were taken at postnatal day 0, day 10 (before eye opening), day 20 (before the critical period) and day 45 (end of development) and subjected to microarray and real-time RT-PCR analyses. A temporal pattern of expression was revealed for 24 genes that continuously increased (18 genes) or decreased (6 genes) as visual cortex development progressed and were common among all age groups. Our data provide a relevant set of genes whose expression levels correlate with visual cortex development and represent a novel group that may affect temporal-specific regulation.

[Effects of all-trans retinoic acid on the rat Müller cell in vitro].

PURPOSE: To investigate the effects of various concentrations of all-trans retinoic acid (RA) on the rat Müller cells in vitro. METHODS: A rat Müller cell line was used in this study. Rat Müller cells were cultured with varying levels of RA for 24 h to 48 h. We examined cellular morphology under phase contrast microscope, cell proliferation using MTT assay, viable cell numbers by hemocytometer counting and cell apoptosis with flow cytometry. RESULTS: At lower concentration (< 0.1 microM), RA didn't change the cell's appearance and didn't inhibit the cell proliferation (P > 0.05). However, at higher concentration (1 microM, 10 microM, 100 microM), RA could inhibit the proliferation of Müller cells accompanied with morphological changes in a time- and dose-dependent manner. Furthermore, different concentration of RA (5 microM, 10 microM, 20 microM) could induce cell apoptosis. When using 20 microM RA to treat cells for 48 h, a significant decrease in cell numbers and an obvious increment of apoptotic cells were observed. The percentage of apoptotic cell was (35.87 +/- 7.40)% (P < 0.01, vs. control). CONCLUSIONS: RA can inhibit the proliferation and induce the apoptosis of müller cells in a time- and dose-dependent manner.