miR-142 downregulation alleviates the impairment of spatial learning and memory, reduces the level of apoptosis, and upregulates the expression of pCaMKII and BAI3 in the hippocampus of APP/PS1 transgenic mice.

MicroRNA-142-5p (miR-142-5p) has been found to be dysregulated in several neurodegenerative disorders. However, little is known about the involvement of miR-142-5p in Alzheimer's disease (AD). Brain angiogenesis inhibitor 3 (BAI3), which belongs to the adhesion-G protein-coupled receptor subgroup, contributes to a variety of neuropsychiatric disorders. Despite its very high expression in neurons, the role of BAI3 in AD remains elusive, and its mechanism at the cellular and molecular levels needs to be further elucidated. The current study sought to investigate whether miR-142-5p influenced BAI3 expression and neuronal synaptotoxicity induced by Aß, both in APP/PS1 transgenic mice and a cellular model of Alzheimer's disease. Altered expression of miR-142-5p was found in the hippocampus of AD mice. Inhibition of miR-142 could upregulate BAI3 expression, enhance neuronal viability and prevent neurons from undergoing apoptosis. In addition, the reduction of phosphorylation of Synapsin I and calcium/calmodulin-dependent protein kinase II (CaMKII), as well as the expression of PSD-95 in the hippocampus of APP/PS1 transgenic mice, were significantly restored by inhibiting miR-142. Meanwhile, the levels of Aß1-42, ß-APP, BACE-1 and PS-1 in cultured neurons were detected, and the effects of inhibiting miR-142 on spatial learning and memory were also observed. Interestingly, we found that BAI3, an important regulator of excitatory synapses, was a potential target gene of miR-142-5p. Collectively, our findings suggest that miR-142 inhibition can alleviate the impairment of spatial learning and memory, reduce the level of apoptosis, and upregulate the expression of pCaMKII and BAI3 in the hippocampus of APP/PS1 transgenic mice; thus, appropriate interference of miR-142 may provide a potential therapeutic approach to rescue cognitive dysfunction in AD patients.

Combine intravitreal bevacizumab with Nd: YAG laser hyaloidotomy for valsalva pre-macular haemorrhage and observe the internal limiting membrane changes: a spectralis study.

Valsalva retinopathy was described as a particular form of retinopathy, pre-retinal and subinternal limiting membrane haemorrhages in nature that rarely may break through and become subhyloid or intravitreal, secondary to a sudden increase in intrathoracic pressure. We reported a new way that Nd:YAG laser for ILM hyaloidotomy in order to drain the sub-ILM blood into vitreous cavity combined with intravitreal bevacizumab to improve the absorption of blood. Therapeutic alliance make significant outcome, protecting vision in time. We used spectralis OCT to observe sub-ILM mix cells and special ILM structure in this lesion for the first time, as the spectralis OCT can reach histology level imagination.

Expressions of survivin and vascular endothelial growth factor in a Murine model of proliferative retinopathy.

AIM: To examine the expression of survivin and vascular endothelial growth factor(VEGF) during the development of retinal neovascularization (NV) in a mouse model. METHODS: A well-characterized murine model of retinal NV was used to study the expression of survivin and VEGF. NV of the retina was induced in mice by exposure to 75% O(2) from postnatal day P7 to P12, followed by return to room air from P12 to P17. Expression of survivin and VEGF protein was analyzed by Immunohistochemistry. In addition, mouse model of proliferative retinopathy was analyzed by retinal fluorescein angiography and quantification analysis. RESULTS: The normal mice had both superfiekal and deep vascular layers that extended from the optic nerve to the periphery. In intraocular pressure(IOP) mice were characterized by represent a typical pattern of pathological retinal NV. There are less or little nuclei of new vessels vascular endothelial cell breaking through the inner retinal than in retinopathy of prematurity (ROP) mice, large clusters of blood vessels were adherent to the internal limiting membrane(ILM) (0.27±0.20 vs 23.38±1.027, t=9.454, P<0.001). During the angiogenic period from P13 to P17, survivin and VEGF protein expression increased in experimental retinas compared with control samples(2.56±0.46 vs 3.34±0.40, t=17.43, P<0.01: 2.18±0.75 vs 4.34±0.25, t=19.61, P<0.01). Protein levels of VEGF and survivn has significantly positive correlation (P<0.05, r=0.411). CONCLUSION: Correlation was made at the protein levels of survivin expression compared with that of VEGF in a murine model of retinal NV, which suggests a temporal role for survivin and VEGF in new vessel formation in response to hypoxic stimulation.

Hospital based epidemiological study for diabetic retinopathy: study design and preliminary results.

AIM: To describe the design and preliminary results of the hospital based epidemiological study for diabetic retinopathy(HBESDR), an ongoing epidemiological study to estimate the prevalence of diabetic retinopathy(DR) and to elucidate the clinical, anthropometric, biochemical and any other risk factors associated with diabetic retinopathy. METHODS: Totally 2000 diabetes will be recruited from the Diabetes eye clinic in the First Affiliated Hospital of China Medical University. All subjects underwent blood sugar estimation and Oral Glucose Tolerance Test to diagnose diabetes. All diabetes would undergo complete questionnaire, a comprehensive eye examination. Blood and urine would be collected for biochemical investigations. All fundus photographs for any DR will be graded. Participants who need treatment will be sent to the ophthalmic clinic and follow-up interval program for all subjects will be suggested. A computerized database is created for the records. RESULTS: To date, 1174 diabetes have been recruited, there were 350(29.81%) DR in all diabetes, most of them were with mild non-proliferative diabetic retinopathy (NPDR) (139, 39.71%); 71(20.29%) moderate NPDR, 66(18.86%) severe NPDR, 74(21.14%) proliferative diabetic retinopathy (PDR). Females, longer duration of diabetes, family history of diabetes and hypertension had a statistically significant increase in risk of any DR. CONCLUSION: The study is expected to provide an estimate of the overall prevalence of DR and the prevalence with different duration of diabetes and also a better understanding of the risk factors associated with DR.

Epidemic studies of diabetic retinopathy in China-a review.

The prevalence of diabetic retinopathy (DR) is increasing dramatically as the population of patients with diabetes continues to rise. This paper wants to investigate the prevalence and risk factors of DR in China through reviewing the research from Pubmed about population-based epidemic studies. The results of observational studies suggested that the overall prevalence of DR was 1.6%-6.5% in population, 19.9%-43.1% in diabetes and 13.6% in population without diabetes, most of the DR were the mild type, macular edema and vision-threatening were 5.2% and 1.2%. The risk factors for DR were longer duration of diabetes, plasma glucose concentration, concentrations of HbA(1)c level, higher systolic blood pressure(BP), higher diastolic BP, male gender, rural region, and methods of diabetic treatment and so on. The prevalence of DR which was strongly related to duration of diabetes was higher with the increase of diabetes. DR would be the major leading cause of visual impairment in China, it is very important to prevent DR by early screening and any other methods.