Inhibition of hsa_circ_0002570 suppresses high-glucose-induced angiogenesis and inflammation in retinal microvascular endothelial cells through miR-1243/angiomotin axis.

Diabetic retinopathy (DR) is the most severe microvascular complication of diabetes and a major cause of visual impairment and blindness. However, the treatment for DR is still limited. Our study aimed to explore the role of circular RNA_0002570 in DR. First, we predicted the potential microRNA and mRNA that could bind to circ_0002570 and identified the miR-1243 and angiomotin gene; then, we used RT-PCR and Western blot to measure their expression. Next, we evaluated the abilities of proliferation, migration, and angiogenesis in vitro in human retinal microvascular endothelial cells (hRMECs) by CCK-8, transwell assay, and tube formation assay, respectively. To analyze the relationship among miR-1243, circ_0002570, and angiomotin, RNA pull-down and luciferase assay were performed. Our results showed that, in DR patients and high-glucose-induced hRMECs, miR-1243, circ_0002570, and angiomotin were all abnormally expressed. MiR-1243 could directly and competitively bind to both circ_0002570 and angiomotin mRNA to inhibit their expression. Moreover, circ_0002570 suppressed the abilities of proliferation, migration, and angiogenesis in hRMECs induced by high glucose, which was dependent on miR-1243-angiomotin axis. Furthermore, circ_0002570 could upregulate angiomotin by targeting miR-1243 to mediate the dysfunction of hRMECs induced by high glucose. In conclusion, circ_0002570 might serve as a potential target for diagnosis and treatment for DR.

Soluble expression of recomb inant cMyc, Klf4, Oct4, and Sox2 proteins in bacteria and transduction into living cells.

AIM: To develop a new method to produce recombinant reprogramming proteins, cMyc, Klf4, Oct4, and Sox2, in soluble format with low cost for the generation of induced pluripotent stem cells (iPSCs). METHODS: A short polypeptide sequence derived from the HIV trans-activator of transcription protein (TAT) and the nucleus localization signal (NLS) polypeptide were fused to the N terminus of the reprogramming proteins and they were constructed into pCold-SUMO vector which can extremely improve the solubility of recombinant proteins. Then these vector plasmids were transformed into E. coli BL21 (DE3) Chaperone competent cells for amplification. The solubility of these recombinant proteins was determined by SDS-PAGE and Coomassie brilliant blue staining. The recombinant proteins were purified by Ni-NTA resin and identified by Western blot. The transduction of these proteins into HEK 293T cells were evaluated by immunofluorescence staining. RESULTS: These four reprogramming proteins could be produced in soluble format in pCold-SUMO expression vector system with the assistance of chaperone proteins in bacteria. The proteins were purified successfully with a purity of over 70% with a relative high transduction rate into 293 cells. CONCLUSION: The results in the present study indicate the four important reprogramming proteins, cMyc, Klf4, Oct4, and Sox2, can be produced in soluble format in bacteria with low cost. Our new method thus might be expected to greatly contribute to the future study of iPSCs.

Refractive Errors in Northern China Between the Residents with Drinking Water Containing Excessive Fluorine and Normal Drinking Water.

The purpose of this study was to evaluate the refractive errors and the demographic associations between drinking water with excessive fluoride and normal drinking water among residents in Northern China. Of the 1843 residents, 1415 (aged ≥40 years) were divided into drinking-water-excessive fluoride (DWEF) group (>1.20 mg/L) and control group (≤1.20 mg/L) on the basis of the fluoride concentrations in drinking water. Of the 221 subjects in the DWEF group, with 1.47 ± 0.25 mg/L (fluoride concentrations in drinking water), the prevalence rates of myopia, hyperopia, and astigmatism were 38.5 % (95 % confidence interval [CI] = 32.1-45.3), 19.9 % (95 % CI = 15-26), and 41.6 % (95 % CI = 35.1-48.4), respectively. Of the 1194 subjects in the control group with 0.20 ± 0.18 mg/L, the prevalence of myopia, hyperopia, and astigmatism were 31.5 % (95 % CI = 28.9-34.2), 27.6 % (95 % CI = 25.1-30.3), and 45.6 % (95 % CI = 42.8-48.5), respectively. A statistically significant difference was not observed in the association of spherical equivalent and fluoride concentrations in drinking water (P = 0.84 > 0.05). This report provides the data of the refractive state of the residents consuming drinking water with excess amounts of fluoride in northern China. The refractive errors did not result from ingestion of mild excess amounts of fluoride in the drinking water.

A novel MIP gene mutation analysis in a Chinese family affected with congenital progressive punctate cataract.

Congenital cataracts are one of the leading causes of visual impairment and blindness in children, and genetic factors play an important role in their development. This study aimed to identify the genetic defects associated with autosomal dominant congenital progressive punctate cataracts in a Chinese family and to explore the potential pathogenesis. Detailed family history and clinical data were recorded, and all the family members' blood samples were collected for DNA extraction. Linkage analysis was performed by microsatellite markers that are associated with punctate cataracts, and logarithm (base 10) of odds (LOD) scores were calculated using the LINKAGE program. Positive two-point LOD scores were obtained at markers D12S1622 (Zmax = 2.71 at θ = 0.0), D12S1724 (Zmax = 2.71 at θ = 0.0), and D12S90 (Zmax = 2.71 at θ = 0.0), which flank the major intrinsic protein of lens fiber (MIP) gene on chromosomal region 12q13. Direct sequencing of the encoding region of the MIP gene revealed a novel mutation (G>D) in exon 4 at nucleotide 644, which caused a substitution of glycine to aspartic acid at codon 215 (p.G215D) for the MIP protein. The mutation cosegregated with all patients with congenital progressive punctate cataracts, but it was absent in the healthy members. Bioinformatics analysis predicted that the mutation affects the function of the MIP protein. The wild type (WT) and G215D mutant of MIP were transfected with green fluorescent protein (GFP) into Hela cells separately, and it was found that the G215D mutant was aberrantly located in the cytoplasm instead of in the plasma membrane. In summary, our study presented genetic and functional evidence linking the new MIP mutation of G215D to autosomal dominant congenital cataracts, which adds to the list of MIP mutations linked to congenital progressive punctate cataracts.

A novel mutation in the connexin 46 (GJA3) gene associated with congenital cataract in a Chinese pedigree.

PURPOSE: To identify the potential pathogenic mutation in a three-generation Chinese family with congenital nuclear pulverulent cataracts. METHODS: A three-generation pedigree was recruited for our study. Three patients and four healthy members of the family underwent a comprehensive clinical examination. Genomic DNA extracted from peripheral blood was amplified using the polymerase chain reaction (PCR) method and the exons of all candidate genes were sequenced. RESULTS: When sequencing the encoding regions of the candidate genes, a novel mutation (c.559C>T) was identified in the gap junction protein alpha 3 (GJA3) gene, which resulted in the substitution of highly conserved proline by serine at codon 187 (P187S). There was no noticeable nucleotide polymorphism in other candidate genes. The mutation co-segregated with all patients, but was absent in the healthy members and 100 normal individuals. CONCLUSIONS: The present study identified a novel mutation (c.559C>T) in the GJA3 gene associated with autosomal dominant pulverulent cataracts in a Chinese family. As the first report to relate p.P187S mutation in GJA3, it expands the mutation spectrum of GJA3 in association with congenital cataracts.

Polymorphisms of the DNA repair genes XPD and XRCC1 and the risk of age-related cataract development in Han Chinese.

PURPOSE: Epidemiological evidence suggests that ultraviolet (UV) irradiation and oxidative stress play an important role in age-related cataract pathogenesis. UV irradiation and oxidative stress can produce a wide range of DNA damage. Polymorphisms of DNA repair enzymes may affect repair efficiency and the role of DNA repair mechanisms has received attention recently in age-related cataract pathogenesis. In this case-control study, The aim was to determine the frequency of polymorphisms in two DNA repair enzyme genes, xeroderma pigmentosum complementation group D (XPD) codon 751 and x-ray cross-complementing group 1 (XRCC1) codon 399, in patients with age-related cataract and in healthy controls. METHODS: Polymerase chain reaction and restriction fragment length polymorphisms were used to analyze XPD T751G and XRCC1 G399A in 180 patients with age-related cataract and 174 healthy individuals as controls. RESULTS: There was a significant difference between the case and control groups in the XRCC1399 genotype. The odds ratio of the XRCC1 G/A polymorphism compared with the G/G wild-type genotype was 1.92 (95% CI = 1.17-3.15, p = 0.01). Moreover, individuals who carried at least one A-allele (G/A or A/A) had a 1.68-fold increased risk of developing age-related cataract compared with those who carried the G/G wild type genotype (OR = 1.68; 95% CI: 1.05-2.68, p = 0.030). No statistically significant difference was found in the genotypic and allelic distributions of the polymorphisms in the XPD gene between the groups. CONCLUSIONS: These results suggest that polymorphisms in XRCC1 codon 399 may be associated with the development of age-related cataract in Han Chinese.

Genetic analysis of the FOXL2 gene using quantitative real-time PCR in Chinese patients with blepharophimosis-ptosis-epicanthus inversus syndrome.

PURPOSE: The purpose of this study was to identify the mutation(s) or deletion(s) of the forkhead box protein L2 (FOXL2) gene in Chinese patients with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES). METHODS: Genomic DNA extracted from peripheral blood was collected from two Chinese families and from one sporadic case. PCR direct sequencing and quantitative real-time PCR-based copy number screening for the whole exon of FOXL2 were performed. RESULTS: Direct sequencing revealed an indel mutation c.50C→TA in the sporadic case which resulted in a frameshift generating 78 novel amino acids and terminating prematurely at codon 95. Deletions in the FOXL2 gene were confirmed by quantitative real-time PCR (q-real-time PCR) in two families in which intragenic mutations were excluded by direct sequencing. These changes containing deletions and a de novo mutation were not detected either in the non-carrier relatives or in 100 normal controls. CONCLUSIONS: This study identified two deletions and a de novo mutation in the FOXL2 gene in Chinese BPES patients. This is the first study to report FOXL2 gene deletions detected by q-real-time PCR in this ethnic group. This technique enriches the diagnostic methods of molecular genetics in BPES patients. The de novo mutation expands the mutation spectrum of FOXL2.