Myopia is a major problem of public health in China, and even in the world, and slowing down the progress of myopia has become a hot issue of concern. However, the effects of the current therapeutic and interventional modalities to myopia, including optical lenses, chemical drugs, and laser surgery, the effect of treatment and intervention is not very satisfactory, and these modalities may incur some side effects. This situation suggests that the pathogenic and regulatory mechanisms of myopia remain elusive, and the myopia treatments lack the accurate and effective targets to the etiology. A complete visual experience depends on the entire visual pathway from the retina to the visual cortex, in which any structural and functional defect can lead to visual abnormalities. In recent years, with the advances in the infrared spectroscopy and the magnetic resonance imaging technology, more and more evidence has shown that the progression of myopia is related to the visual cortex. Improving the functional connectivity and blood prefusion between different regions of the visual cortex may impede myopia profession. In-depth understanding of the interaction between myopia and the visual cortex is helpful to search for accurate and effective myopia treatment targets and novel intervention strategies.
OBJECTIVE The effect of platelet-derived wound healing factor (PDWHF) on wound healing in diabetic rats was studied. METHODS Forty-four male SD rats were randomly divided into 2 groups. Thirty-two rats of experimental group accepted intraperitoneal injection of alloxan (1.5 mg/10 g body weight). Within one or two days after injection, while the blood sugar of the rats was higher than 180 mg/dl, the animal model of diabetic rat should have been established. Then a dorsal incision was given to every rat. After the addition of PDWHF (the experimental group) or bovine albumin (the control group), the incision was sutured up. Seven, ten and fourteen days after operation, the breaking strength of the wound was measured. On another hand, specimen from the wound was taken for the culture of fibroblasts. When the cultured fibroblasts have been incubated with 10% PDWHF for 4, 8 and 12 hours, the procollagen I (alpha 1) mRNA levels were examined respectively, and compared with those of control. RESULTS Significant difference in wound breaking strength had been observed between PDWHF-treated incisions and the control on 7, 10 and 14 days after wounding (P lt; 0.01). Experiment in vitro demonstrated that the procollagen I (alpha 1) mRNA levels in wound fibroblasts incubated with 10% PDWHF for 4, 8 and 12 hours were 0.9, 3.7 and 2.2 folds higher than those in fibroblasts in control. CONCLUSION It was suggested that direct stimulation of procollagen I (alpha 1) gene expression was one of the ways that PDWHF played its role in accelerating wound healing.
This experiment was designed to observe the proliferative effects of platelet derived wound healing factor (PDWHF) of different concentrations on fibroblasts from rat wounds and on epithelial from human wounds. Cultured fibroblasts from rat wound and epithelia from human wound were randomly divided into three groups. (1) In blank control, the cells were treated with basic medium (BM, contains 1640/0.5% FCS); (2) the positive control, the cells were treated with 1640/10% FCS and (3) in the PDWHF group, the cells were treated respectively with BM/1% PDWHF, BM/3% PDWHF, BM/5% PDWHF, BM/7% PDWHF, BM/10% PDWHF, BM/12% PDWHF, respectively. The Cells were collected after 48 hours culturing with BM or PDWHF, and the cell proliferation was measured by MTT method according to the OD values. The result showed that the PDWHF could remarkably enhance the proliferation of fibroblasts and epithelial cells when its concentration was between 1% and 7%, which was obviously higher than that of the blank control (P lt; 0.01). When the concentration of PDWHF reached 10%, its proliferative effect was not remarkable when compared with the blank control, When the concentration of PDWHF reached 12%, it showed inhibitory effect on fibroblasts and manifested no obvious inhibitory effect on epithelial cells. It was concluded that the PDWHF was a combination of a variety of growth factors. In a certain range of concentration, the PDWHF might effectively promote the proliferation of fibroblasts and epithelial cells. Howerve, when its concentration reached to relatively higher level, its effect was not remarkable any more, or even showed inhibitory effect on cell proliferation.
It was reported in this article that a preparation of acid/heat-stable peptides (AHSP) from pig serum with a molecular-weight less than 18 ku a without antigenity and toxicity could exert enhancement effect on wound healing. Two pieces of polyvinyl alcohol (PVA) sponge implanted in rat dorsal subcutaneous pouchs of 20 mice were selected as the wound model. The subcutaneous pouch having one piece of sponge was taken as the experimental group and the other as the control. Injection of 50 microliters of such peptide preparation into the test sponge was performed once a day from the time of injury on for 5 consecutive times, while 50 microliters of BSA (5 mg/ml) into the control sponge in the same way. The levels of total DNA, protein and hydroproline in AHSP-treated sponge were observed significantly higher than those in the control sponge on the 7th and 10th days after wounding (P lt; 0.05). No significant difference was seen on the 14th postinjury day (P gt; 0.05). The effect of AHSP on proliferation of wound fibroblast cultured in vitro was also detected. In conclusion, such peptides derived from pig serum had the activity to accelerate wound healing without resultant excessive healing and its direct stimulation of the proliferation of wound fibroblast was probably one of the way which AHSP exerted its action.
Abstract To study the regulation of growth and proliferation of tissue-repair cell from wound microenvironment, the effects of wound fluid (WF) on the growth and proliferation of wound fibroblast were studied in vitro. Thirty rats were divided into 6 groups. On the back of every rat, an incision of 0.5～1.0cm was performed a subcutaneous sac was made by blunt dissection. A piece of sponge was put in, and the wound was sutured. After 1,3,7,9,11,15 days, one group of the rats were sacrificed respectively, and WF was collected from the sponge. Two kinds of medium were made with each WF: 1640+1%FCS+10%WF and1640+10%FCS+10%WF. After 48 hours incubation with newly prepared wound fibroblasts, the growth of the cells was observed. It was shown that (1) Under 1%FCS, WFfrom1,3,7 days stimulated cell proliferation, and WF from 9,11,15 days caused cell death. (2) Under 10%FCS, WF from 9,11,15 days inhibited cell growth. It was suggested that the wound microenvironment stimulated the fibroblasts to proliferate for one week after injury, and beyond that further growth seemed to be arrested, and that there might be some growth inhibitory factors present in the microenvironmentduring the late stage of wound healing.
Objective To analyze the risk factors of postoperative vitreous hemorrhage (PVH) after pars plana vitrectomy (PPV) for vitreous hemorrhage (VH) secondary to retinal vein occlusion (RVO). Methods A retrospective case-control study. A total of 195 RVO patients (195 eyes) with VH were first treated with PPV from November 2015 to December 2021 were included in this study. There were 102 males (102 eyes) and 93 females (93 eyes), with an age of (62.93±9.78) years. The patients were divided into PVH group (17 patients, 8.72%) and non-PVH group (178 patients, 91.28%) according to the occurrence of PVH. The time of occurrence of PVH was (140.33±130.85) days after PPV. All eyes were performed 23G or 25G systematic PPV by the same doctor. During the operation, different types of intraocular tamponade and intravitreal injection of anti-vascular endothelial growth factor or triamcinolone acetonide after operation were selected according to the severity of retinopathy. The follow-up time was (9.45±6.68) months. The baseline systemic parameters, ocular parameters and intraoperative parameters affecting the occurrence of PVH were analyzed. Baseline systemic parameters included sex, age, diabetes mellitus and hypertension; ocular parameters included RVO type, lens status, VH course, preoperative best corrected visual acuity and intraocular pressure; intraoperative parameters included cataract phacoemulsification, removal of internal limiting membrane, type of intraocular tamponade, type of intravitreal injection drug at the end of operation, etc. Kaplan-Meier survival analysis, and Cox univariate and multivariate regression analysis were performed to analyze the risk factors of PVH after PPV in RVO with VH patients. Results In PVH group, the number of patients with diabetes was more than that in the non-PVH group, and the course of diabetes was longer, and differences were statistically significant. There were significant differences in RVO type, lens status and type of intraocular tamponade. Univariate Cox regression analysis showed that the combination with diabetes [odds ratio (OR)=2.724, 95% confidence interval (CI) 1.006-7.374, P=0.049], duration of diabetes (OR=1.071, 95%CI 1.013-1.134, P=0.016), central retinal vein occlusion (OR=4.387, 95%CI 1.421-13.546, P=0.010), intraocular lens (OR=3.493, 95%CI 1.229-9.925, P=0.019), and intraocular gas tamponade (OR=3.640, 95%CI 1.365-9.702, P=0.010) were associated with PVH. Multivariate Cox regression analysis showed that intraocular gas tamponade was independent risk factor for PVH. Conclusion Intraocular gas tamponade can increase the risk of PVH after PPV in patients with VH secondary to RVO.
With the surged prevalence of myopia, the pathogenic mechanism underlying myopia has attracted attention. At present, it is generally believed in the flied that the reduced blood perfusion in the choroid is crucial for myopigenesis. Then, in the process of myopigenesis, how are the blurred visual signals transmitted to the choroidal blood vessels through the retina and retinal pigment epithelium, leading to the reduced choroidal blood perfusion. The cellular and molecular mechanisms underpinning this process remain elusive. In recent years, the theory of scleral hypoxia has attracted much attention. Popular signaling molecules in current research include dopamine, epidermal growth factor, retinoic acid, cholinergic molecules and adenosine, etc. These factors are likely to participate in signal transduction in retina and RPE, thus causing changes in choroidal blood flow and affecting the occurrence and development of myopia. Therefore, these signaling factors and their downstream pathways may provide new ideas for the prevention and control of myopia targets.
Objective To study the differential expression profiling of the transcripts modified by m5C methylation in a rat model of N-methyl-D-aspartate (NMDA)-induced retinal excitotoxicity. MethodsA total of 65 Sprague Dawley male rats aged 7-8 weeks were randomly divided into two groups: normal control group and NMDA group. The right eye (model eye) of rats in the NMDA group were injected with 50.0 mmol/L of NMDA 3 μl in the vitreous cavity, while in the normal control group, equal volume of normal saline was injected into the vitreous cavity. After 1 week of the injection, the optic nerve conduction function of rats was detected by visual evoked potential. The whole structure of rat retina was observed by hematoxylin-eosin staining, and the thickness of each retinal layer and the number of retinal ganglion cell layer were detected. The number of β3 tubulin immunofluorescence positive cells was detected by immunofluorescence staining on retinal stretched preparation. Total RNA was extracted from the retinas of normal control group and NMDA group, and high-throughput m5C modified RNA was sequenced, and bioinformatics analysis was performed. The relative expression levels of SLFN3, PLXNB3, CD36 and HIC2 mRNA in retina were detected by real-time quantitative polymerase chain reaction. The comparison between the two groups was performed using an unpaired t test. ResultsThe P1 latency of control group and NMDA group were (117.86±6.48) and (148.46±3.78) ms, and the amplitudes were (42.57±2.41) and (8.68±0.63) μV, respectively. Compared with the normal control group, the latency period was prolonged and the amplitude was significantly decreased in the NMDA group, with statistical significance (P＜0.001). In normal control group, retinal ganglion cells (RGC) were uniformly arranged with large round nuclei. In NMDA group, the volume of retinal RGC was atrophied and the number of RGC was reduced. The total retinal thickness in the control group and NMDA group was (207.51±12.76) μm and (187.51±12.54) μm, respectively. The number of β3 tubulin positive cells was 79.86±6.56 and 29.36±2.16, respectively. Compared with normal control group, the total retinal thickness and the number of β3 tubulin positive cells in NMDA group were decreased, with statistical significance (P＜0.001). Compared with the control group, 576 differentially expressed m5C mRNA were screened in the NMDA group, among which 230 up-regulated and 346 down-regulated genes were detected, respectively. The results of biological information analysis showed that compared with the control group, the upregulated m5C mRNA in the NMDA group was mainly involved in biological processes such as perception and cell-cell adhesion, and was mainly concentrated in the cytokine-cytokine receptor interaction and neural active ligand-receptor interaction pathway. The biological processes in which down-regulated m5C mRNA was mainly involved in biological processes such as G-protein-coupled receptor signaling pathway and cell communication, which were mainly concentrated in primary immune deficiency pathway and neural active ligand-receptor interaction pathway. Real-time quantitative polymerase chain reaction detection results showed that compared with the normal control group, the relative expression levels of SLFN3 and PLXNB3 mRNA in the retina of rats in NMDA group were significantly increased, while the relative expression levels of CD36 and HIC2 mRNA were significantly decreased, with statistical significance (P＜0.05). ConclusionIn NMDA induced retinal excitatory toxicity rat models, m5C modified retinal transcriptome showed abnormal expression.
ObjectiveTo analyze the protein expression changes in the retina of non-arteritic anterior ischemic optic neuropathy (NAION) in rats.MethodsThe rat NAION (rNAION) model was established by Rose Bengal and laser. Twenty Sprague-Dawley rats were randomly divided into 4 groups, the normal control group, the laser control group, the RB injection control group, and the rNAION model group, with 5 rats in each group. The right eye was used as the experimental eye. The retina was dissected at the third day after modeling. Enzyme digestion method was used for sample preparation and data collection was performed in a non-dependent collection mode. The data were quantitatively analyzed by SWATH quantitative mass spectrometry, searching for differential proteins and performing function and pathway analysis.ResultsCompared with the other three control groups, a total of 184 differential proteins were detected in the rNAION group (expression fold greater than 1.5 times and P＜0.05), including 99 up-regulated proteins and 85 down-regulated proteins. The expressions of glial fibrillary acidic protein, guanine nucleotide binding protein 4, laminin 1, 14-3-3γ protein YWHAG were increased. Whereas the expressions of Leucine-rich glioma-inactivated protein 1, secretory carrier-associated membrane protein 5, and Clathrin coat assembly protein AP180 were decreased. The differential proteins are mainly involved in biological processes such as nerve growth, energy metabolism, vesicle-mediated transport, the regulation of synaptic plasticity, apoptosis and inflammation. Pathway enrichment analysis showed that PI3K-Akt signaling pathway and complement and thrombin reaction pathway was related to the disease.ConclusionThe protein expressions of energy metabolism, nerve growth, synaptic vesicle transport and PI3K-Akt signaling pathway can regulate the neuronal regeneration and apoptosis in NAION.
ObjectiveTo observe the inhibitory effect of lentiviral vector miR-191 (LV-191) on retinal neovascularization (RNV) in mice model of oxygen-induced retinopathy (OIR).MethodsEighty healthy 7-day-old C57BL/6J mice were randomly divided into 5 groups including normal group, non-intervention group, normal saline (NS) group, LV-191 group and LV-green fluorescent protein (GFP) group, 16 mice in each group. The OIR model was established in the non-intervention group, NS group, LV-191 group and LV-GFP group. NS group, LV-191 group and LV-GFP group were given an intravitreal injection of 1 μl of NS, LV-191 and LV-GFP at the age of 12 days. No injection was performed in the non-intervention group. In normal group,newborn mouse were maintained in room air form P0 to P17, and no treatment was performed. Mice in all five groups were euthanized at P17. Retinal neovasculation (RNV) was evaluated by counting the number of pre-retinal neovascular cells and analysis of non-perfusion area area by immunofluorescent staining of the mouse retina. Real-time quantitative PCR (RT-PCR) to detect miR -191 and P21 expression of retinal tissue.ResultsIn the LV-191 group, the non-perfusion area were both significantly smaller than those in non-intervention group, NS group and LV-GFP group (F=127.20, P＜0.001). The number of pre-retinal neovascular cell nuclei in retinas from LV-191 group were obviously lower than those in the retinas from non-intervention group, NS group and LV-GFP group (F=31.71, P＜0.05). RT-PCR showed that the LV-191 and P21 level of LV-191 group increased significantly than other groups (F=10.95, 15.60; P＜0.05).ConclusionIntravitreal injection of LV-191 inhibits RNV in mice model of OIR possibly through up-regulating p21.