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.
The debate on the cell of origin of human retinoblastoma lasted for more than one century. In the recent issue of ldquo;cellrdquo;, David Cobrinikprime;s group shows that L/M cone precursors are the most likely answer as they have an intrinsic circuitry, including murine double minute 2 (MDM2), Nmyc, the nuclear receptors retinoid X receptor and thyroxine receptor 2, making them extremely sensitive to transformation following retinoblastoma gene inactivation.
Objective To investigate the cellular viability and mitochondrial reactive oxygen species (ROS) production of the Müller cells under high glucose condition, and explore the protection role of the 5,6-dihydrocyclopenta-1, 2-dithiole-3-thione (CPDT) on Müller cells. Methods Müller cells from Sprague Dawley rats were divided into 5 groups randomly, including 25 mmol/L normal glucose group (group A) and 65 mmol/L high glucose group (group B). High glucose group with 45, 60, 70 μmol/L CPDT and cultured them 72 hour was set as group C, D and E. Water soluble tetrazolium salt (WST)-8 was used to measure the cellular viability. Flow cytometry was used to measure the active oxygen and apoptosis index. The expression of nuclear factor erythroid 2-related factor 2 (Nrf2), hemeoxygenase-1 (HO-1), Bcl-2 and Bax protein were measured by Western blot. Results Compared with group A, the WST-8 showed that the viability of Müller cells apparently decreased in group B (t=39.59,P＜0.05). Compared with the group B, the viability of Müller cells had changes in group C (t=0.97,P＞0.05), but recovered in group D and E (t=?4.17, ?7.52;P＜0.05). Compared with group A, the FCM showed that the mitochondrial ROS levels was higher in group B (t=?30.99,P＜0.05). Compared with group B, the mitochondrial ROS levels were decreased in group D (t=27.68,P＜0.05). Compared with group A, Bax, Nrf2 and HO-1 increased (t=–11.03, –63.17, –11.44;P＜0.05), while the bcl-2 decreased in group B (t=7.861,P＜0.05). Compared with the group B, Nrf2, HO-1 and Bax decreased (t=15.11, 26.59, 6.27;P＜0.05), while the bcl-2 increased in group D (t=?6.53,P＜0.05). Conclusions Under the high glucose, CPDT may reduce the mitochondrial ROS levels and the expression of Nrf2, HO-1 and Bax protein of Müller cells. It may inhibit apoptosis through activating the Nrf2/HO-1 pathway and balancing of level of Bcl-2 protein and mitochondrial ROS.
Objective To investigate the effect of intravitreal injection with dexamethasone on leukocyte accumulation, vascular permeability, and the expression of intercellular adhension molecule (ICAM-1) in rats with diabetes. Methods Seventy-two BN rats were divided into 4 groups: control group, diabetes group, diabetes+ physiologic saline group, and diabetes+ dexamethasone group, with 18 rats in each group. Streptozotocin was injected into the rats to set up the diabetic model. Accumulated leukocytes were counted in vivo by acridine orange leukocyte fluorography, and retinal vascular permeability was measured by Evans blue assay. The expression of mRNA and protein level of ICAM-1 were evaluated by real-time quantitative polymerase chain reaction analysis and enzymelinked immunosorbent assay. Results In the diabetes+ dexamethasone group, accumulated leukocytes were reduced, retinal vascular permeability decreased, and the expression of ICAM-1 decreased. The expression of ICAM-1 mRNA and protein levels in control group, diabetes group, diabetes+ physiologic saline group, and diabetes+ dexamethasone group were 0.43plusmn;0.07，0.76plusmn;0.21，0.74plusmn;0.18，and 0.55plusmn;0.13; (37.90plusmn;4.56), (76.74plusmn;6.68), (74.32plusmn;7.11), and (39.61plusmn;4.47) pg/mg respectively. Conclusions Dexamethasone can reduce accumulated leukocytes and retinal vascular permeability, which may be caused by inhibiting the expression of ICAM-1. (Chin J Ocul Fundus Dis,2007,23:273-276)
Objective To observe the effect of ginsenoside Rg3 on the proliferation, migration, and tube formation of human retinal capillary endothelial cell (HRCEC) cultured in normal and hypoxia condition. Methods HRCEC was cultured in normal condition and treated with 0.0 mmol/L (group A), 0.1 mmol/L (group B) and 0.5 mmol/L (group C) ginsenoside Rg3. HRCEC was also cultured in hypoxia condition and treated with 0.0 mmol/L (group D), 0.1 mmol/L (group E) and 0.5 mmol/L (group F) ginsenoside Rg3. The effects of ginsenoside Rg3 on HRCEC proliferation were measured by methylthiazoletrazolium assay in 24, 48 and 72 hours after culture. In 24 hours after culture, the effect of cell migration was evaluated by transwell chamber; the effect of tube formation was evaluated by Matrigel; the expression of vascular endothelial growth factor (VEGF) protein and mRNA were detected by Western blot and real-time quantitative reverse transcription-polymerase chain reaction. Results Ginsenoside Rg3 could inhibit proliferation of HRCEC, depending on the concentration (F=30.331 and 33.402 in normal and hypoxia condition, respectively; P＜0.05) and time (F=85.462 and 136.045 in normal and hypoxia condition, respectively; P＜0.05). The number of cell migration was 103.33plusmn;3.54, 92..25plusmn;3.68, 78.64plusmn;4.66 in group A, B and C, the difference among three groups was statistically significant (F=28.801, P＜0.05). The number of cell migration was 125.76plusmn;3.11, 90.27plusmn;3.55, 77.81plusmn;5.01 in group D, E and F, the difference among three groups was statistically significant (F=117.594, P＜0.05). The number of tube formed in Matrigel was 24.3plusmn;2.2, 15.7plusmn;1.7, 10.1plusmn;2.3 in group A, B and C, the difference among three groups was statistically significant (F=35.364, P＜0.05). The number of tube formed in Matrigel was 26.2plusmn;1.9, 15.1plusmn;2.6, 8.6plusmn;1.9 in group D, E and F, the difference among three groups was statistically significant (F=50.989, P＜0.05). The expression of VEGF mRNA was 1.00plusmn;0.06, 0.79plusmn;0.06, 0.68plusmn;0.02 in group A, B and C, the difference among three groups was statistically significant (F=31.303, P＜0.05). The expression of VEGF mRNA was 3.88plusmn;0.12, 2.83plusmn;0.09, 1.15plusmn;0.05 in group D, E and F, the difference among three groups was statistically significant (F=682.668, P＜0.05). The expression of VEGF protein was 0.62plusmn;0.03, 0.41plusmn;0.02, 0.32plusmn;0.02 in group A, B and C, the difference among three groups was statistically significant (F=125.471, P＜0.05). The expression of VEGF protein was 0.91plusmn;0.03, 0.82plusmn;0.03, 0.71plusmn;0.02 in group D, E and F, the difference among three groups was statistically significant (F=41.045, P＜0.05). Conclusion Ginsenoside Rg3 can inhibit the proliferation, migration, and tube formation of HRCEC through the inhibition of VEGF expression.
Objective To observe the influence of interleukin-1beta; (IL-1beta;) on the expression of phosphorylated signal transducers and activators of transcription 3 (pSTAT 3) in rat retinal Muuml;ller cells.Methods For in vitro study cultured Muuml;ller cells were treated with IL-1beta; of different concentrations (0, 0.1, 1, 5 and 10 ng/ml) for 24 hours. For in vivo study, 32 Sprague-Dawley（SD）rats were divided into 4 groups randomly (control group，100，500 and 1000 ng/ml group) with 8 rats in each group. After 24 hours of injection with phosphate buffered solution (PBS), or 100,500,1000 ng/ml IL-1beta; into the vitreous cavities of the above rats, retinas were harvested. The expressions of pSTAT3 in cultured Muuml;ller cells or treated retinas were evaluated by indirect immunofluorescence and western blotting.Results After 24 hours of incubation without IL-1beta;, pSTAT3 has little expression in cultured Muuml;ller cells, but was upregulated by 1 ng/ml or higher IL-1beta; in a dosagedependent manner (F=46.64, 43.78;P＜0.01). pSTAT3 was not expressed in adult rat retina, but was upregulated by vitreous injection of 100 ng/ml or higher IL-1beta; in a dosagedependent manner (F=73.53,43.70;P＜0.01).pSTAT3 expressed mainly in inner nuclear layer and ganglion cell layer. Doublelabeling showed that there was no costaining of pSTAT3 and glial fibrillary acidic protein (GFAP) in retina of control group, but there were many costained Muuml;ller cells in retinas treated with IL-1beta;.Conclusions Expression of pSTAT3 in Muuml;ller cells could be activated by IL-1beta; which may represent one pathway link to reactive gliosis.
ObjectiveTo observe the effect of phase Ⅱenzyme inducer 5, 6-dihydrocyclopenta 1, 2-dithiole-3-thione (CPDT) on nuclear factor erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) signal pathway and oxidative stress in the retina of type 2 diabetic rats. MethodsThirty-five male Wistar rats were randomly divided into two group, normal group and model group. Model group were further randomly divided into two group, diabetic group and CPDT intervention group. There were 8 rats in the normal group and 27 rats in the model group. Diabetic group and CPDT intervention group were given high fat and high sugar diet for 2 months. After 12 hours of fasting, type 2 diabetic rat model was induced by intraperitoneal injection of low dose of streptozotocin. CPDT was added into the high fat and high sugar diets at 1 week after the diabetic model was established in the CPDT intervention group. Eight weeks after CPDT treatment, blood glucose, serum malondialdehyde (MDA), blood lipid, Nrf2 and hemeoxygenase-1 (HO-1) expression were evaluated. ResultsType 2 diabetic model was successfully established in 25 rats, the success rate was 92.6%.The level of blood lipid of diabetic group was higher than those of the normal group (FTC=65.866, FTG=25.441, FLDL-C=38.889; P=0.000). Blood glucose was significant different between all groups (χ2=25.812, P=0.000), and was significantly higher in diabetic group than that in normal group and CPDT intervention group. The serum MDA content was significant different between all groups (F=59.545, P=0.000), and was significantly higher in diabetic group than that in normal group (t=10.523, P=0.000) and CPDT intervention group (t=7.766, P=0.000). The mRNA level of retinal Nrf2 and HO-1 was significant different between all groups (FNrf2=19.503, PNrf2=0.000;FHO-1=9.737, PHO-1=0.001), and was higher in CPDT intervention group than the diabetic group (tNrf2=3.399, PNrf2=0.002;tHO-1=2.167, PHO-1=0.039). The protein level of retinal Nrf2 and HO-1 was significant different between all groups (FNrf2=112.823, FHO-1=119.361; P=0.000), and was higher in CPDT intervention group than the diabetic group (tNrf2=6.203, tHO-1=6.388; P=0.000). Immuno-staining showed that Nrf2 and HO-1 were mainly expressed in retinal ganglion cell layer, inner plexiform layer and inner nuclear layer, and were significant different between all groups (FNrf2=16.206, FHO-1=46.790; P=0.000). They also were higher in CPDT intervention group than the diabetic group (tNrf2=3.172, PNrf2=0.003;tHO-1=6.321, PHO-1=0.000), was higher in diabetic group than that in normal group (tNrf2=2.679, PNrf2=0.011;tHO-1=3.482, PHO-1=0.001). ConclusionCPDT may activate Nrf2/ARE pathway, induce Nrf2 and HO-1 expression, decrease serum MDA and blood glucose, and thus reduce oxidative stress injury in the retina of type 2 diabetic rats.
ObjectiveTo observe the expression of vascular endothelial growth inhibitor (VEGI, TL1A), vascular endothelial growth factor (VEGF), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in diabetes rats' serum, vitreous and retina, and discuss the role of VEGI in the pathogenesis of diabetic retinopathy (DR). MethodsA total of p70 adult male Wistar rats were randomly divided into 4 groups, the control group (10 rats), the diabetes mellitus (DM) 1 month group (20 rats), the DM 3 month group (20 rats) and the DM 6 month group (20 rats). Cytokines of serum and vitreous were determined by enzyme-linked immunosorbent assay (ELISA), and the concentrations of the cytokines in the retina were determined by immunohistochemistry on paraffin retinal sections. Hematoxylin-eosin (HE) staining of retina was used to estimate the pathological change of DR. The results were analyzed by one-way analysis of variances, independent samples t-test and LSD test. ResultsThe serum TL1A levels of the control group, the DM 1 month group, the DM 3 month group and the DM 6 month group rats were (92.09±2.05), (118.36±8.30), (85.90±7.51) and (78.90±4.88) ng/L respectively, the level of TL1A in serum of the DM 1 month group, the DM 3 month group and the DM 6 month group were significantly lower than that of the control group (F=77.405, P < 0.05). The concentration of serum TNF-α and IL-1β increased after DM model was established (F=3.508, 15.416; P < 0.05); the VEGF level in serum showed no difference between the groups (F=1.242, P > 0.05). The vitreous TL1A levels of the control group, the DM 1 month group, the DM 3 month group and the DM 6 month group were (91.50±8.18), (67.03±6.74), (47.44±4.92) and (46.01±4.62) ng/L respectively, every DM groups showed significant difference with the control group (F=114.777, P < 0.05); VEGF level in vitreous increased from 1 month after DM model was established (F=8.816, P < 0.05); TNF-α and IL-1β level in vitreous also showed an upward tendency (F=4.392, 3.635; P < 0.05). Paraffin section immunohistochemistry showed that the absorbance (also called optical density) of TL1A of the DM 1 month group and the DM 3 month group were significantly lower than that of the control group (t=6.851, 6.066; P < 0.05), but the DM 6 month group showed no difference with the control group (t=1.401, P > 0.05); the level of VEGF and TNF-α in DM groups were higher than that of the control group (tVEGF=-4.709, -16.406, -9.228; tTNF-α=-4.703, -6.583, -17.762; P < 0.05); the level of IL-1β were significantly higher in the DM 1 month group and the DM 6 month group (t=-4.108, -3.495; P > 0.05); but the DM 3 month showed no difference with the control group (t=-0.997, P > 0.05). HE staining of retina showed that the retina of the control group and the DM 1 month group had normal retinal structures, the DM 3 month group had retinal edema and disorganization, the DM 6 month group had severe retinal edema, deep stain of ganglion cells, and more neovascularization in inner plexiform layer. ConclusionVEGI is involved in the pathogenesis of DR, and it might interacts with VEGF, TNF-α and IL-1β to affect the development of DR.
Objective To observe the microvessel density（MVD）and expression of vascular endothelial growth factor (VEGF) in retinoblastoma（RB）before and after comprehensive treatment and explore its clinical correlations with tumor infiltration and recurrence. Methods Sixty-one paraffin specimens of RB were divided into enucleation without comprehensive treatment group (untreated group，52 cases), planned enucleation before comprehensive treatment group (planned enucleation group，six cases) and tumor recurrence after comprehensive treatment group（recurrence group，three cases）. There were optic nerve invasion in 19 cases，no optic nerve infiltration in 33 cases. The MVD and VEGF expressions of 61 paraffin specimens were detected by streptavidin biotin-peroxidase (SP) immunohistochemistry with monoclonal antibody of CD34 and VEGF. Real time PCR was performed for the VEGF expression of planned enucleation group and recurrence group.Results In the untreated group，the MVD and VEGF expression of optic nerve infiltration cases were significantly higher than those of cases without optic nerve infiltration（t=-2.4685, P=0.017; chi;2=8.416 6，P=0.032 8）.Tumor microvessel regression, decreased MVD, occlusion and hyaline changes of blood vessels were observed in the planned enucleation group in the course of systemic chemotherapy. Many neovascularized capillaries and increased MVD were observed in tumor tissues of the recurrence group. The VEGF expression of planned enucleation group was lower than that in the recurrence group.Conclusions There was no significant difference on VEGF expression in RB between with and without comprehensive treatment. The increasing MVD and VEGF expression of cases without comprehensive treatment were related to the optic nerve infiltration. And the increasing MVD may also play an important role in RB recurrence after comprehensive treatment.
Stem cells are crucial for embryonic development and in the maintenance of adult cellular homeostasis. Understanding the regulatory network of stem cells, including embryonic and adult stem cells, will allow us to learn the pathogenesis and possibly design novel approaches to treat many diseases (such as cancer and degeneration). The retinoblastoma (Rb) pathway controls cellular proliferation, differentiation and death. More and more evidences support an important role of Rb activity in the biology of stem and progenitor cells. Transiently inactivating Rb pathway might favor the expanding of functional stem cell populations, thus have values in the future stem cell applications.