Search

Aim: To explore the correlation of gut microbiota and the metabolites with the progression of diabetic retinopathy (DR) and provide a novel strategy to elucidate the pathological mechanism of DR., Methods: The fecal samples from 32 type 2 diabetes patients with proliferative retinopathy (PDR), 23 with non-proliferative retinopathy (NPDR), 27 without retinopathy (DM), and 29 from the sex-, age- and BMI- matched healthy controls (29 HC) were analyzed by 16S rDNA gene sequencing. Sixty fecal samples from PDR, DM, and HC groups were assayed by untargeted metabolomics. Fecal metabolites were measured using liquid chromatography-mass spectrometry (LC-MS) analysis. Associations between gut microbiota and fecal metabolites were analyzed., Results: A cluster of 2 microbiome and 12 metabolites accompanied with the severity of DR, and the close correlation of the disease progression with PDR-related microbiome and metabolites were found. To be specific, the structure of gut microbiota differed in four groups. Diversity and richness of gut microbiota were significantly lower in PDR and NPDR groups, than those in DM and HC groups. A cluster of microbiome enriched in PDR group, including Pseudomonas , Ruminococcaceae-UCG-002 , Ruminococcaceae-UCG-005 , Christensenellaceae-R-7 , was observed. Functional analysis showed that the glucose and nicotinate degradations were significantly higher in PDR group than those in HC group. Arginine, serine, ornithine, and arachidonic acid were significantly enriched in PDR group, while proline was enriched in HC group. Functional analysis illustrated that arginine biosynthesis, lysine degradation, histidine catabolism, central carbon catabolism in cancer, D-arginine and D-ornithine catabolism were elevated in PDR group. Correlation analysis revealed that Ruminococcaceae-UCG-002 and Christensenellaceae-R-7 were positively associated with L-arginine, ornithine levels in fecal samples., Conclusion: This study elaborates the different microbiota structure in the gut from four groups. The relative abundance of Ruminococcaceae-UCG-002 and Parabacteroides are associated with the severity of DR. Amino acid and fatty acid catabolism is especially disordered in PDR group. This may help provide a novel diagnostic parameter for DR, especially PDR., Competing Interests: Conflicts of Interest: Jiang SQ, None; Ye SN, None; Huang YH, None; Ou YW, None; Chen KY, None; Chen JS, None; Tang SB, None., (International Journal of Ophthalmology Press.)

Induced pluripotent stem cells (iPSCs) were firstly induced from mouse fibroblasts since 2006, and then the research on iPSCs had made great progress in the following years. iPSCs were established from different somatic cells through DNA, RNA, protein or small molecule pathways and transduction vehicles. With continuous improvement of technology on reprogramming, the induction of iPSCs became more secure and effective, and showed enormous promise for clinical applications. We reviewed different reprogramming of somatic cells, four kinds of pathways of reprogramming and three types of transduction vehicles, and discuss the research of iPSCs in ophthalmology and the prospect of iPSCs applications.

Aim: To detect the expression of transforming growth factor beta-induced gene (TGFBI) protein in human corneal tissue and overexpress it in the human corneal epithelial cells in order to discuss the function of TGFBI in the pathogenesis of corneal dystrophy., Methods: Immunohistochemistry (IHC) was used to detect the expression of TGFBI in the human cornea tissue. TGFBI cDNA was obtained by reverse transcription-PCR from human corneal total RNA extracted from cornea transplant donor and cloned into pCMV-N-HA vector. The recombinant pCMV-N-HA-TGFBI plasmid transfected human corneal epithelial cells. Forty-eight hours later, mRNA and proteins were harvested from cells for real-time PCR analysis and western blot assay respectively., Results: IHC indicated TGFBI mainly exist below the human corneal epithelium layer. Transfection of recombinant pCMV-N-HA-TGFBI into human corneal epithelial cells resulted in effective expression of TGFBI, as shown by increased mRNA level detected by real-time PCR as well as increased protein level detected by Western blot. Meanwhile the result of real-time PCR and Western blot shown the expression of MMP1, MMP3 (matrix metalloproteinases MMP) increased while the expressin of TIMP1 (tissue inhibitors of matrix metalloproteinases TIMP) decreased., Conclusion: TGFBI mainly exists below the corneal epithelial layer, recombinant eukaryotic expression vector harboring human TGFBI cDNA was obtained and efficiently overexpressed in human corneal epithelial cells. Meanwhile the TGFBI overexpression in human corneal epithelial cells result in MMP1, MMP3 increasing and TIMP1 decreasing. The result might be helpful for studying the function and role of TGFBI in pathogenesis of corneal dystrophy.