Objective To study the differentially expressed genes (DEG) during the differentiation of human induced pluripotent stem cells (hiPSC) and human embryonic stem cells (hESC) into pericytes and endothelial cells, and to identify key molecules and signaling pathways that may regulate this differentiation process. MethodshiPSC and hESC were selected and expanded using mTeSR medium. A "two-step method" was used to induce the differentiation of hiPSC and hESC into pericytes and endothelial cells. Pericytes were identified using immunofluorescence staining, while endothelial cells were isolated and identified using flow cytometry. Total RNA samples were extracted on days 0, 4, 7, and 10 of differentiation and consistently significant DEGs were screened. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) signal pathway enrichment analysis were performed on the screened DEGs. ResultsBoth hiPSCs and hESCs successfully differentiated into pericytes and endothelial cells under induction conditions. Transcriptome sequencing results showed that with the extension of differentiation time, the DEGs in hiPSCs and hESCs were significantly upregulated or downregulated, following a generally consistent trend. During the differentiation process, marker genes for pericytes and endothelial cells were significantly upregulated. A total of 491 persistent DEGs were detected in both hiPSC and hESC, with 164 unique to hiPSCs and 335 to hESCs, while 8 DEGs were co-expressed in both cell lines. Among these, SLC30A3, LCK, TNFRSF8, PRDM14, and GLB1L3 showed sustained downregulation, whereas CLEC18C, CLEC18B, and F2RL2 exhibited sustained upregulation. GO enrichment analysis revealed that DEGs with sustained upregulation were primarily enriched in terms related to neurogenesis, differentiation, and developmental proteins, while DEGs with sustained downregulation were enriched in terms related to membrane structure and phospholipid metabolic processes. KEGG pathway analysis showed that upregulated genes were primarily enriched in cancer-related pathways, pluripotency regulatory pathways, the Wnt signaling pathway, and the Hippo signaling pathway, whereas downregulated genes were predominantly enriched in metabolism-related pathways. ConclusionsDuring the differentiation of hiPSC and hESC into pericytes and endothelial cells, 8 DEGs exhibit sustained specific expression changes. These changes may promote pericyte and endothelial cell differentiation by activating the Wnt and Hippo pathways, inhibiting metabolic pathways, releasing the maintenance of stem cell pluripotency, affecting the cell cycle, and inhibiting cell proliferation.
Objective To observe the expression of vascular endothelial growth factor receptor-1 (VEGFR-1) and VEGFR-2 in hypoxic chorioretinal endothelial cells of monkeys (RF/6A), and to evaluate the effect of minocycline. Methods RF/6A was cultured and divided into four groups: control group, hypoxia group, hypoxia and low dose of minocycline group (0.5 mu;mol/L), hypoxia and medium dose of minocycline group (5 mu;mol/L), and hypoxia and high dose of minocycline group (50 mu;mol/L). Real-time reverse transcriptionpolymerase chain reaction (RT-PCR) and immunohistopathological staining were used to measure the mRNA and protein expression of VEGFR-1 and VEGFR-2, respectively. Results RT-PCR showed that the expression of VEGFR-1 mRNA did not vary significantly between groups (F 24 h=0.17,F 48 h=1.53,F72 h=2.04;P＞0.05). Compared with hypoxia group, the expression of VEGFR-2 mRNA in all minocycline treated groups were significantly downregulated (low minocycline, medium minocycline, high minocycline: t=4.69, 20.16, 17.12; P＜0.001). The immunohistopathological study showed the cells with positive staining of VEGFR-1 can be observed in all groups, and the staining was relatively weak and mainly located in cell membrane and cytoplasm. The optical density value analysis showed that the protein expression of VEGFR-1 did not vary significantly between groups at all time points（F 24 h=0.251,F 48 h=0.340,F72 h=0.589;P＞0.05）. The VEGFR-2 positive staining cells were also observed in all groups, and the staining was relatively high. Brown staining particles of VEGFR-2 were observed in the cell membrane with minor staining particles in cytoplasm. The staining density of VEGFR-2 was significantly higher in hypoxia group than control group. Compared with the hypoxia group, the protein expression of VEGFR-2 in minocycline treated groups was significantly lower（F 24 h=19.147,F 48 h=14.893,F72 h==11.984; P＜0.05). Conclusion The expression of VEGFR-2 is upregulated in RF/6A, and minocycline somewhat shows an inhibition effect.
Objective To clarify that the vascular endothelial cell injury caused by obstructive sleep apnoea hypopnea syndrome (OSAHS) is partly mediated by miRNA-92a. Methods Serum miRNA-92a level was measured in patients who underwent polysomnography between January 2018 and December 2018. The correlation between miRNA-92a and OSAHS was analyzed. Meanwhile, endothelial cells were cultured in vitro, and morphological changes and JC-1 staining results of endothelial cells were observed after OSAHS serum stimulation, so as to further clarify the injury of endothelial cells. The changes of miRNA-92a target gene were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot to further clarify the mechanism of endothelial cell injury. Results Seventy-two patients received polysomnography, including 22 cases in the non-OSAHS group, 18 in the mild OSAHS group, 10 in the moderate OSAHS group, and 22 in the severe OSAHS group. Serum miRNA-92a level was significantly increased in the OSAHS patients, and it also increased with the aggravation of OSAHS severity. OSAHS serum significantly damaged endothelial cells. Endothelial cells were swollen, disordered arrangement, and unclear boundaries. JC-1 staining showed that green fluorescence was significantly enhanced compared with the control group. RT-PCR and Western blot showed that the expressions of Krüppel-like factor-2 (KLF-2), Krüppel-like factor-4 (KLF-4) and endothelial nitric oxide synthase (eNOS) were significantly decreased under OSAHS serum stimulation. Conclusion Serum miRNA-92a of OSAHS patients is significantly increased, and reduces the expression of target genes KLF-2, KLF-4 and eNOS, affects the mitochondrial function of endothelial cells, and injures endothelial cells.
ObjectiveTo investigate the influence of Ataxia-telangiectasia mutated (ATM) activation on cellular oxidative stress induced by high glucose in bovine retinal capillary endothelial cells(BRECs).
Methods The BRECs were treated by different culture medium with various glucose concentrations (5 mmol/L glucose, 30 mmol/L glucose, 30 mmol/L glucose+10 μmol/L KU55933) as normal glucose group, high glucose group and treatment group respectively.After the cells incubated for 48 hours, the protein expression of ATM, P-ATM, Mitogen-Activated Protein Kinase P38(P38), P-P38, Extracellular signal-regulated kinases(ERKs), P-ERKs was detected by Western blot; cellular ROS level was detected by Reactive Oxygen Species Assay Kit; propidium iodide/Hoechst staining was used for analysis of apoptosis; the expression of vascular endothelial growth factor (VEGF) in the supernatant was determined by Enzyme-Linked Immunosorbent Assay (ELISA); the paracellular permeability between endothelium cells was detected by FITC-dextran.
ResultsCompared with the protein level of P-ATM, P-P38 and P-ERKs in high glucose group increased. Especially, P-P38, P-ERKs expressed much more than in high glucose group. The secretion of VEGF in high glucose group was higher than that in the normal glucose group but less than that in treatment group. The same tendency existed in ROS assay, apoptosis assay and paracellular permeability measuring.
ConclusionsHigh glucose induced altered activation of ATM which might play a protective role in cellular oxidative stress. Deficiency of ATM might lead to ROS explosion, cell apoptosis and dysfunction of endothelial barrier. The mechanism might be associated with P38, ERKs and VEGF.
ObjectiveTo construct the connective tissue growth factor (CTGF) recombinant interference vector (shRNA) and observe its inhibitory effect on the expression of endogenous CTGF in retinal vascular endothelial cells. Methods The human CTGF shRNA was constructed and the high-titer CTGF shRNA lentivirus particles was acquired via three-plasmid lentivirus packaging system to infect retinal vascular endothelial cells. The optimal multiplicity and onset time of lentivirus infection were identified by tracing down the red florescent protein in interference vector. The cells were classified into three groups: blank control group, infection control group and CTGF knockdown group. The differences in cells migrating ability was observed through Transwell allay. The mRNA and protein expression of CTGF, fibronectin, α-smooth muscle actin (α-SMA) and collagen Ⅰ (Col Ⅰ) were quantified through real-time PCR testing and Western blot system. Data between the three groups were examined via one-way analysis of variance. ResultsThe result showed that an optimal multiplicity of 20 and onset time of 72 hours were the requirements to optimize lentivirus infection. Transwell allay result showed a contrast in the number of migrated cells in the CTGF knockdown group and that in the blank control group and infection control group (F=20.64, P=0.002). Real-time PCR testing showed a contrast in related gene expression (CTGF, fibronectin, α-SMA and Col Ⅰ) in the CTGF knocked-down group and that in the blank control group and infection control group (F=128.83, 124.44, 144.76, 1 374.44; P=0.000, 0.000, 0.000, 0.000). Western blot system showed the statistical significance of the contrasted number of related protein expression (CTGF, fibronectin, α-SMA and Col Ⅰ) in the knockdown group and that in the blank control group (F=22.55, 41.60, 25.73, 161.68; P=0.002, 0.000, 0.001, 0.000). ConclusionThe success in producing CTGF shRNA lentivirus particle suggests that CTGF shRNA lentivirus can effectively knock down CTGF expression.
Objective To observe the influences of uncoupling protein 2 (UCP-2) rs660339 variants transfection on cell proliferation and apoptosis of human umbilical vein endothelial cell (HUVEC). Methods Two UCP-2 green fluorescent protein (GFP) lentivirus constructs were created with the rs660339 locus carried C or T (UCP-2C or UCP-2T), respectively. HUVEC were cultured after lentiviral infection of UCP-2C or UCP-2T. The expression of UCP-2C or UCP-2T was detected with real time polymerase chain reaction. Cell proliferation and cell apoptosis were compared among negative control (NC) group, UCP-2T group and UCP-2C group using CCK-8 cell viability and flow cytometry. Western blot and immunostaining were employed to examine the expression of Bcl-2 gene. Results The lentivirus constructs were successfully created. ＞80% of the transfected cells were found to express GFP under fluorescent microscope. The mRNA levels of UCP-2 gene were significantly increased (F=29.183,P=0.001) in the UCP-2T group and UCP-2C group. The CCK-8 assay revealed that on day two (F=15.970,P=0.004), day three (F=16.738,P=0.004), day four (F=5.414,P=0.045) post-infection, UCP-2T and UCP-2C group showed significantly greater proliferation than the NC cells. The apoptotic rate in the UCP-2T and UCP-2C group was significantly lower than NC group (F=277.138,P=0.000), and the apoptotic rate of UCP-2T was significantly lower than that of UCP-2C (P=0.003). The protein levels of Bcl-2 in the UCP-2T and UCP-2C group were significantly greater than that in the NC group (F=425.679,P=0.000), and the Bcl-2 expression of UCP-2T was greater than that of UCP-2C (P=0.002). The Bcl-2 density in the UCP-2T and UCP-2C group were greater than that in the NC group (F=11.827,P=0.008), while there was no difference between UCP-2T and UCP-2C group (P=0.404). Conclusion The variants of UCP-2 rs660339 may influence HUVEC proliferation and apoptosis, and UCP-2T showed a stronger effect of inhibiting apoptosis than UCP-2C.
Objective
To explore the effect and mechanism of ultrashort wave (USW) for prevention and treatment of vascular crisis after rat tail replantation.
Methods
Eighty 3-month old female Sprague Dawley rats (weighing 232.8-289.6 g) were randomly divided into 5 groups. In each group, based on the caudal vein and the coccyx was retained, the tail was cut off. The tail artery was ligated in group A; the tail artery was anastomosed in groups B, C, D, and E to establish the tail replantation model. After surgery, the rats of group B were given normal management; the rats of group C were immediately given intraperitoneal injection (3.125 mL/kg) of diluted papaverine hydrochloride injection (1 mg/mL); the rats of groups D and E were immediately given the local USW treatment (once a day) at anastomotic site for 5 days at the dosage of 3 files and 50 mA for 20 minutes (group D) and 2 files and 28 mA for 20 minutes (group E). The survival rate of the rat tails was observed for 10 days after the tail replantation. The tail skin temperature difference between proximal and distal anastomosis was measured at pre- and post-operation; the change between postoperative and preoperative temperature difference was calculated. The blood plasma specimens were collected from the inner canthus before operation and from the tip of the tail at 8 hours after operation to measure the content of nitric oxide (NO).
Results
The survival rates of the rat tails were 0 (0/14), 36.4% (8/22), 57.1% (8/14), 22.2% (4/18), and 75.0% (9/12) in groups A, B, C, D, and E, respectively, showing significant overall differences among 5 groups (χ2=19.935, P=0.001); the survival rate of group E was significantly higher than that of group B at 7 days (P lt; 0.05), but no significant difference was found between the other groups by pairwise comparison (P gt; 0.05). At preoperation, there was no significant difference in tail skin temperature difference among 5 groups (P gt; 0.05); at 8 hours, 5 days, 6 days, and 7 days after operation, significant overall difference was found in the change of the skin temperature difference among groups (P lt; 0.05); pairwise comparison showed significant differences after operation (P lt; 0.05): group B gt; group D at 8 hours, group C gt; group D at 5 days, groups A, B, and C gt; group D at 6 days, groups B and C gt; groups A and E, and group B gt; group D at 7 days; but no significant difference was found between the other groups at the other time points (P gt; 0.05). Preoperative plasma NO content between each group had no significant difference (P gt; 0.05). The overall differences had significance in the NO content at postopoerative 8 hours and in the change of the NO content at pre- and post-operation among groups (P lt; 0.05). Significant differences were found by pairwise comparison (P lt; 0.05): group D gt; groups A, B, and C in the plasma NO content, group D gt; groups A and B in the change of the NO content at pre- and post-operation; but no significant difference was found between the other groups by pairwise comparison (P gt; 0.05).
Conclusion
Rat tail replantation model in this experiment is feasible. USW therapy can increase the survival rate of replanted rat tails, reduce skin temperature at 7 days, improve blood supply, increase the content of nitric oxide at the early period and prevent vascular crisis.
Objective To explore the effect of bone morphogenetic protein 4 (BMP4) on the glycolysis level of human retinal microvascular endothelial cells (hRMECs). MethodsA experimental study. hRMECs cultured in vitro were divided into normal group, 4-hydroxynonenal (HNE) group (4-HNE group) and 4-HNE+BMP4 treatment group (BMP4 group). 4-HNE group cell culture medium was added with 10 μmmol/L 4-HNE; BMP4 group cell culture medium was added with recombinant human BMP4 100 ng/ml after 6 h stimulation with 10 μmol/L 4-HNE. The levels of intracellular reactive oxygen species (ROS) were detected by flow cytometry. The effect of 4-HNE on the viability of cells was detected by thiazole blue colorimetry. Cell scratch test and Transwell cell method were used to determine the effect of 4-HNE on cell migration. The relative expression of BMP4 and SMAD9 mRNA and protein in normal group and 4-HNE group were detected by real-time quantitative polymerase chain reaction and Western blot. Seahorse XFe96 cell energy metabolism analyzer was used to determine the level of intracellular glycolysis metabolism in normal group, 4-HNE group and BMP4 group. One-way analysis of variance was used for comparison between groups. ResultsThe ROS levels in hRMECs of normal group, 4-HNE group and BMP4 group were 21±1, 815±5, 810±7, respectively. Compared with the normal group, the levels of ROS in the 4-HNE group and the BMP4 group were significantly increased, and the difference was statistically significant (F=53.40, 50.30; P＜0.001). The cell viability in the normal group and 4-HNE group was 1.05±0.05 and 1.28±0.05, respectively; the migration rates were (0.148±0.005)%, (0.376±0.015)%; the number of cells passing through the pores were 109.0±9.6, 318.0±6.4, respectively. Compared with the normal group, the 4-HNE group had significantly higher cell viability, cell migration rate, and the number of cells passing through the pores, and the differences were statistically significant (F=54.35, 52.84, 84.35; P＜0.05). The relative expression levels of BMP4 and SMAD9 mRNA in the cells of the 4-HEN group were 1.680±0.039 and 1.760±0.011, respectively; compared with the normal group, the difference was statistically significant (F=53.66, 83.54; P＜0.05). The relative expression levels of BMP4 and SMAD9 proteins in the cells of the normal group and 4-HEN group were 0.620±0.045, 0.860±0.190, 0.166±0.049, 0.309±0.038, respectively; compared with the normal group, the differences were statistically significant (F=24.87, 53.84; P＜0.05). The levels of intracellular glycolysis, glycolytic capacity and glycolytic reserve in normal group, 4-HNE group and BMP4 group were 1.21±0.12, 2.84±0.24, 1.78±0.36, 2.59±0.11, 5.34±0.32, 2.78±0.45 and 2.64±0.13, 5.20±0.28, 2.66±0.33. Compared with the normal group, the differences were statistically significant (4-HNE group: F=86.34, 69.75, 58.45; P＜0.001; BMP4 group: F=56.87, 59.35, 58.35; P＜0.05). There was no significant difference in intracellular glycolysis, glycolysis capacity and glycolysis reserve level between 4-HNE group and BMP4 group (F=48.32, 56.33, 55.01; P＞0.05). ConclusionBMP4 induces the proliferation and migration of hRMECs through glycolysis.
Objective To explore morphological recellularization level of bioprosthetic valve scaffold (BVS) and to provide researching means for fabricating tissue engineered heart valve in vitro.Methods The homograft bioprosthetic aortic tube valve was selected as BVS, which was conserved by liquid nitrogen, and its endothelial cells (ECs) were removed by 0.1% sodium dodecylsulphate (SDS). As implantation cells, the endothelial cells (ECs) differentiating from human bone marrow mesenchymal stem cells (MSCs) in vitro were implanted with high-density seeding (gt;10 5 cells/cm2) on the BVS, which was covered by fibronectin (80 μg/ml) in advance. The complex structure was statically cultured in DMEM (high glucose) with 20% FBS and VEGF (10 ng/ml) for about 20 days in vitro and stained by 0.5% AgNO3. The morphological structure was observed and photographed by stereomicroscope to detect the recellularization level. Results The ECs of the bioprosthetic valve were notonly removed completely, but also the collagen fiber and elastic fibers were reserved. The ECs differentiating from MSCs were successfully implanted on the HBS, whose recellularization levels on 7th, 14th and 20th day were 73%, 85%, and 92% respectively. Conclusion AgNO3 staining technique is effective, convenient, and economic in evaluating the recellularization level of BVS. It is an effective method in morphological observation for fabricating tissueengineered heart valve in vitro.
Objective
To explore transthyretin (TTR) effect on retinal vascular endothelial cells (hREC) under high glucose and hypoxia environment.
Methods
hREC and human retinal pigment epithelial cell (hRPEC) were cultured at low-glucose (LG), high glucose (HG) and hypoxia. The glucose concentration was increased from 5.5 mmol/L up to 25 mmol/L, and hypoxia was induced by 200 μmol/L CoCl2. The cells were divided into LG group, LG-hypoxia group, HG group, HG-hypoxia group according to the different cell culture environment. The growth index was detected at 0, 4, 8, 16, 24, 36, 48, 60, 72 hours after cultured. Furthermore, hREC and hRPEC were also cultured with additional TTR (4 μmol/L), respectively. Then transwell co-culture system was employed to reveal the effects of hRPEC on the growth of hREC.
Results
At 72 hours after cultured, the growth index of hREC and hRPEC in LG group were increased as compared with LG-hypoxia group and HG group (hREC: F=17.098, 22.970; P < 0.05. hRPEC: F=45.442, 9.011; P < 0.05); the growth index of hREC and hRPEC were decreased in HG group and HG-hypoxia group (hREC: F=146.184, P < 0.05；hRPEC: F=27.907, P < 0.05). Additionally, hREC could be significantly repressed by added TTR during culture with high concentration of glucose (F=161.430, 24.106; P < 0.05). hREC could be significantly increased by added TTR during culture with low concentration of glucose (F=200.486, 48.662; P < 0.05). In co-culture process, hRPEC revealed inhibition activity against hREC under both natural and abnormal environment (LG group: F=15.711, P < 0.05; LG-hypoxia group: F=45.659, P < 0.05; HG group: F=7.857, P < 0.05; HG-hypoxia group: F=6.348, P < 0.05).
Conclusion
Under high glucose and hypoxia environment, the growth of hREC from neovascular could be inhibited by TTR.
