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Öğe Effects of Bevacizumab, Ranibizumab, and Aflibercept on MicroRNA Expression in a Retinal Pigment Epithelium Cell Culture Model of Oxidative Stress(Mary Ann Liebert, Inc, 2018) Dinc, Erdem; Ayaz, Lokman; Kurt, Akif HakanPurpose: This study aimed to evaluate the effects of bevacizumab, ranibizumab, and aflibercept on the microRNA (miRNA) expression in human retinal pigment epithelium cell (ARPE-19) culture model of oxidative stress. Methods: Control cells were cultured in the hydrogen peroxide (H2O2)-free medium. In H2O2 group ARPE-19 cells were exposed to 600M H2O2 alone for 18h. In study groups, cells were preincubated with bevacizumab, ranibizumab, and aflibercept (1.25-2.5, 0.5 and 2.0mg/mL, respectively) for 3h before H2O2 exposure. Another group of ARPE-19 cells were incubated with drugs for 3h without H2O2 exposure. Cell viability and vascular endothelial growth factor (VEGF) levels were evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and enzyme-linked immunosorbent assay. The expression levels of 1,152 miRNAs were determined by quantitative real-time PCR. Results: Incubation with 600M H2O2 alone for 18h decreased cell viability by approximate to 50%. Cell viability was greater in the anti-VEGF drug groups compared with the H2O2 group, but the differences were not significant (P>0.05). VEGF levels were significantly lower in the anti-VEGF drug groups compared with the H2O2 group (P<0.05 for all study groups), with no significant differences between the study groups (P>0.05). Incubation with anti-VEGF drugs alone had no effect on miRNA expression in ARPE-19 cells. However, preincubation with bevacizumab, ranibizumab, and aflibercept significantly altered the profile of H2O2-modulated miRNA expression. Conclusions: Preincubation with anti-VEGF drugs can alter the miRNA expression profile in response to H2O2-induced oxidative stress, and these drugs may have epigenetic effects.Öğe Effects of Bone Marrow and Adipose-Derived Mesenchymal Stem Cells on microRNA Expressions in Acute Alkaline Corneal Burn(Mary Ann Liebert, Inc, 2021) Dinc, Erdem; Ayaz, Lokman; Kurt, A. Hakan; Dursun, Ozer; Yilmaz, Gulsen; Vatansever, Mustafa; Ozer, OmerPurpose: The aim of this study was to investigate the microRNA (miRNA) expressions of the corneal tissue after an alkaline burn and to compare the efficiency of adipose- and bone marrow-derived mesenchymal stem cells (MSCs) on expressions. Methods: Thirty-two rats were divided into 4 groups. No intervention was made in the control group. A chemical burn was created by applying 4 mu L NaOH soaked in 6 mm filter paper to the right eye of each animal in the other groups. Whereas only subconjunctival 0.1 mL phosphate-buffered saline (PBS) was injected to in the group 1, 2 x 10(6) adipose- or bone marrow-derived MSC in 0.1 mL PBS was injected subconjunctivally to the animals in the remaining groups (groups 2 and 3, respectively). Tissue samples were collected for miRNA analysis on the third day after the burn. Results: When group 1 was compared with the control group, the expression of 3 of 93 miRNAs increased significantly, whereas the expression of 50 miRNAs decreased significantly. Significant changes in miRNA expressions were observed when group 1 was compared with groups 2 and 3. Although a significant change was observed in the expression of 6 miRNAs in the adipose-derived MSC group, it was found that the expression of 65 miRNAs significantly changed in the bone marrow-derived MSC group. Conclusion: This study shows that there are significant changes in some miRNA expressions after corneal alkaline burn and these changes can be reversed with the subconjunctival injection of MSCs.Öğe Effects of Mesenchymal Stem Cells on microRNA Expressions in Acute Alkaline Corneal Burn(Mary Ann Liebert, Inc, 2023) Dinc, Erdem; Ayaz, Lokman; Kurt, A. Hakan; Dursun, Ozer; Yilmaz, Gulsen; Vatansever, Mustafa; Ozer, Omer[Abstract Not Available]Öğe Evaluation of Anti-Inflammatory and Antiapoptotic Effects of Bone Marrow and Adipose-Derived Mesenchymal Stem Cells in Acute Alkaline Corneal Burn(Mary Ann Liebert, Inc, 2021) Dinc, Erdem; Dursun, Ozer; Yilmaz, Gulsen; Kurt, A. Hakan; Ayaz, Lokman; Vatansever, Mustafa; Ozer, OmerPurpose: The aim of the present study is to comparatively evaluate the anti-inflammatory and antiapoptotic effects of bone marrow and adipose-derived mesenchymal stem cells (MSCs) applied subconjunctivally after alkaline corneal burn. Methods: Thirty-two rats were divided into 4 groups and included in the study (n = 8). While no intervention was made in the control group, a chemical burn was created by applying 4 mu L of NaOH soaked in 6 mm filter paper to the right eye of each subject in the other groups under general anesthesia. While only subconjunctival 0.1 mL phosphate-buffered saline (PBS) was injected to in the group 1, 2 x 10(6) adipose or bone marrow-derived MSC in 0.1 mL PBS was applied subconjunctivally to the subjects in the remaining groups (Group 2 and 3, respectively). Tissue samples were collected for histological analysis on the third day after the burn. Tissue samples were evaluated light microscopically and immunohistochemically stained for interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), caspase-3 (Cas-3), and CD68. Results: The IL-1 beta and TNF-alpha staining scores and the number of CD68- and Cas-3-positive stained cells were significantly lower in the groups given bone marrow and adipose-derived MSC compared to the alkaline burn group (P < 0.0001, for all parameters). Epithelial IL-1 beta and TNF-alpha staining scores were significantly lower in the bone marrow-derived MSC group compared to the adipose-derived MSC group (P < 0.0001, for all parameters). Conclusions: The presented study shows that both bone-marrow and adipose-derived MSCs support wound healing in the corneal tissue and strongly suppress the inflammation occured in the tissue.Öğe Evaluation of circulating miRNAs in wet age-related macular degeneration(Molecular Vision, 2014) Ertekin, Sevda; Yildirim, Ozlem; Dinc, Erdem; Ayaz, Lokman; Fidanci, Senay Balci; Tamer, LuluferPurpose: In the present study, we aimed to investigate the changes in plasma miRNA in patients with wet age-related macular degeneration. Methods: The expression profiles of 384 miRNAs in plasma from 33 patients (22 male, 11 female) who were diagnosed with wet age-related macular degeneration with fundus examination, fundus fluorescein angiography, and optical coherence tomography and 31 controls (17 male, 14 female) were evaluated using high-throughput quantitative real-time PCR. Results: Our results demonstrated that the expression level of five miRNAs (miR-17-5p, miR-20a-5p, miR-24-3p, miR-106a-5p, and miR-223-3p) was significantly upregulated in patients with age-related macular degeneration when compared to the control group (p<0.05). The expression level of 11 miRNAs (miR-21-5p, miR-25-3p, miR-140-3p, miR-146b-5p, miR-192-5p, miR-335-5p, miR-342-3p, miR-374a-5p, miR-410, miR-574-3p, and miR-660-5p) was significantly downregulated in patients (p<0.05). In addition, ten miRNAs (miR-26b-5p, miR-27b-3p, miR-29a-3p, miR-139-3p, miR-212-3p, miR-324-3p, miR-324-5p, miR-532-3p, miR-744-5p, and miR-Let-7c) were expressed only in the patient group. Conclusions: Our results suggest that plasma miRNA levels may change in wet age-related macular degeneration. These molecules may have an important therapeutic target in patients who are unresponsive to antivascular endothelial growth factor therapy. However, further studies must be conducted for possible effects of miRNAs in vascular disorders of eye such as age-related macular degeneration.Öğe Evaluation of microRNA responses in ARPE-19 cells against the oxidative stress(Taylor & Francis Ltd, 2018) Ayaz, Lokman; Dinc, ErdemPurpose: This study aimed to determine microRNA (miRNA) expression profile of human retinal pigment epithelium cell (ARPE-19) against the oxidative stress induced by hydrogen peroxide (H2O2).Methods: ARPE-19 cells were incubated with different concentrations of H2O2 (200, 600 and 800M) for 18h, and then cell viability, vascular endothelial growth factor levels and total oxidant status were evaluated. Expressions of 1152 miRNA were determined by quantitative real-time PCR in each group.Results: Expressions of 90 miRNA were significantly changed in the ARPE-19 cells incubated with H2O2 compared to control group. However, miR-143-3p was only found to be expressed in groups incubated with H2O2. While 24 miRNA (hsa-miR-200c-3p, miR-192-5p, miR-194-5p, miR-141-3p, miR-658, miR-18b-5p, miR-486-5p, miR-525-3p, miR-493-3p, miR-518d-3p, miR-29b-1-5p, miR-675-3p, miR-1238-3p, miR-195-3p, miR-1539, miR-490-5p, miR-3200-5p, miR-1273d, miR-130a-5p, miR-30b-5p, miR-1247-5p, miR-1910-5p, miR27a-5p and miR-200b-3p) upregulated due to the increased dose of H2O2, nine miRNA (hsa-miR-96-5p, miR-33a-5p, miR-345-5p, miR-106b-3p, miR-1285-3p, miR-23b-5p, miR-27b-5p, miR-103a-3p and miR-4289) were also found to be downregulated.Conclusion: This study suggests that oxidative stress may be an important factor on expression of miRNAs in ARPE-19 cells. These miRNAs may have a role in the pathogenesis of age-related macular degeneration related to oxidative stress. However, this relationship needs to be examined in new studies by evaluation of pathways and target genes.Öğe Intravitreal bevacizumab effects on VEGF levels in distant organs: an experimental study(Informa Healthcare, 2014) Dinc, Erdem; Yildirim, Ozlem; Yilmaz, S. Necat; Canacankatan, Necmiye; Ayaz, Lokman; Ozcan, Tuba; Temel, Gulhan O.Purpose: The aim of this study was to determine the effects of single-dose intravitreal bevacizumab on the levels of vascular endothelial growth factor (VEGF) in serum and distant organs. Methods: Adult New Zealand albino rabbits (n = 40) were divided into experimental and control groups. Experimental rabbits received a single 0.05 ml intravitreal injection of 1.25 mg bevacizumab (Avastin) into the right eye, and control rabbits (n = 8) received no injection. Following injection, group 1 rabbits (n = 8) were sacrificed on day 1, group 2 rabbits (n = 8) on day 7, group 3 rabbits (n = 8) on day 14, and group 4 rabbits (n = 8) on day 28; control rabbits were sacrificed on day 28. After sacrifice, samples of brain, heart, liver, kidney and blood were collected. Levels of VEGF in serum and tissue were measured using enzyme-linked immunosorbent assay. The presence of bevacizumab was evaluated by immunofluorescence staining in tissues. Results: Positive bevacizumab immunoreactivity was observed in brain, heart and kidney. Serum VEGF levels significantly decreased in groups 3 and 4 compared with controls (p < 0.05). Liver VEGF levels significantly decreased in group 3 compared with controls (p < 0.05). Conclusions: Intravitreal bevacizumab not only may escape from the blood-retinal barrier and enter the general circulation, but also may be disseminated to distant organs. Our study demonstrates that a single dose of intravitreally injected bevacizumab decreases VEGF levels in serum and liver.Öğe Protective Effect of Combined Caffeic Acid Phenethyl Ester and Bevacizumab Against Hydrogen Peroxide-Induced Oxidative Stress in Human RPE Cells(Taylor & Francis Inc, 2017) Dinc, Erdem; Ayaz, Lokman; Kurt, Akif HakanPurpose: This study aimed to evaluate the protective effects of caffeic acid phenethyl ester (CAPE) and combined CAPE-bevacizumab against oxidative stress induced by hydrogen peroxide (H2O2) in human retinal pigment epithelium. Methods: ARPE-19 cells were pretreated with 5, 10, and 30 mu M CAPE alone and in combination with bevacizumab for 3 h, then exposed to H2O2 for 16 h. Cell viability was evaluated with the 3-(4,5dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Vascular endothelial growth factor (VEGF) protein levels in the medium were measured using a human VEGF ELISA kit. Total antioxidant status (TAS) and total oxidant status (TOS) were measured in ARPE-19 cells using the test kit from Rel Assay. Expression levels of VEGF, Bax, Bcl-2, cytochrome c, apoptotic protease activating factor-1 (apaf-1), and caspase-3 were determined using reverse transcription polymerase chain reaction. Results: Pretreatment of ARPE-19 cells with 30 mu M CAPE and combined CAPE-bevacizumab reduced H2O2 mediated cell death. H2O2-induced oxidative stress increased TOS and VEGF production, which was significantly inhibited by CAPE and the CAPE-bevacizumab combination. VEGF, Bax, cytochrome c, apaf-1, and caspase-3 gene expressions were significantly decreased in cells pretreated with 5, 10, and 30 mu M CAPE and combined CAPE-bevacizumab compared to the H2O2 group. In addition, Bcl-2 expression was significantly increased in both the CAPE and CAPE-bevacizumab combination groups compared to the H2O2 group. Conclusions: CAPE has a protective effect on ARPE-19 cells against oxidative stress, and VEGF protein level and expression can be decreased by incubation with different concentrations of CAPE. These results demonstrate that CAPE suppresses the mitochondria-mediated apoptosis in ARPE-19 cells under oxidative stress. In addition, the use of CAPE in combination with bevacizumab has an additive effect.