Inhibitory effect of YC-1,3-(5 '-hydroxymethyl-2 '-furyl)-1-benzylindazole, on experimental choroidal neovascularization in rat
ABSTRACT It was the aim of this study to evaluate the effects of YC-1, 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole, one of the hypoxia-inducible factor 1 (HIF-1) inhibitors, on laser-induced choroidal neovascularization (CNV) in rats.
Thirty female Brown Norway rats underwent laser photocoagulation to induce CNV. Twenty of them (treatment group) were treated with a single intravitreal injection of 5 microg YC-1, and the remaining 10 (control) were sham-treated with a single intravitreal injection of 2.5 mg/ml dimethyl sulfoxide 2 weeks after laser photocoagulation. The expression of HIF-1alpha and vascular endothelial growth factor (VEGF) in CNV was evaluated by immunofluorescence staining. Fluorescein angiography was performed 2 weeks before and 2 weeks after single intravitreal YC-1 (5 microg) and dimethyl sulfoxide (2.5 mg/ml) injection, grading fluorescein leakage from 0 to 3. The size of the CNV was measured on histologic sections.
Both HIF-1alpha and VEGF were expressed in CNV lesions in the control group 4 weeks after laser photocoagulation, whereas the expressions of HIF-1alpha and VEGF were not observed in the intravitreally YC-1-treated group. The mean fluorescein leakage score decreased from 2.56 +/- 0.49 to 0.79 +/- 0.71 in the intravitreally YC-1-injected group and from 2.62 +/- 0.49 to 1.58 +/- 0.60 in the control group. Sixty-eight (71.6%) out of 95 CNV lesions of intravitreally YC-1-treated eyes (71.4%) and 12 (21.8%) out of 55 lesions in DMSO-treated eyes showed a decreased fluorescein leakage score of 2 or more. The mean difference of fluorescein leakage scores between the intravitreally YC-1-treated group and the control group was significant (p = 0.004). The mean thickness of the CNV lesions in the intravitreally YC-1-treated group (27.30 +/- 6.47 microm) was smaller than that of the control group (64.36 +/- 8.26 microm, p < 0.001). There was no ocular inflammation, retina hemorrhage or systemic toxicity induced by YC-1 treatment.
These results suggest that YC-1 inhibits the HIF-1 expression after photocoagulation and suppresses the development of laser-induced CNV formation.
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ABSTRACT: Heat stroke is a life-threatening illness characterized by an elevated core body temperature. Despite adequate lowering of the body temperature and support treatment of multiple organ-system function, heat stroke is often fatal. 3-(5'-Hydoxymethyl-2'-furyl)-1-benzyl-indazol (YC-1) been identified as an activator of soluble guanylate cyclase. To evaluate whether YC-1 protects multiple organ dysfunctions and improves survival during heat stroke and its mechanism. Male Sprague-Dawley rats untreated or treated with either YC-1 or quercetin (heat shock protein (Hsp) 70 inhibitor) were exposures to heat as a model of heat stroke. The mean arterial pressure (MAP), heart rate, rectal temperature (Tco), survival time, and plasma biochemical data, intracellular Hsp70 and heat shock factor-1 expression were measured. The value of MAP, heart rate and Tco of untreated heat stroke (HS) group were all significantly lower than that of normothermal (NT) group. Biochemical markers evidenced that liver and kidney injuries of HS group were significantly higher than that of NT groups. YC-1 (20mg/kg) pretreatment with heat stroke (YC-1+HS) group, the MAP and heart rate were return to normal, and the biochemical markers were all significantly recovered to normal. The survival time of HS group, NT group and YC-1+HS group were 21, 480, and 445min, respectively. The expression of Hsp70 and HSF-1 in liver and renal of YC-1+HS group was significantly higher than that of HS group. All of the protective effects of YC-1 were all significantly suppressed when pretreated with quercetin (400mg/kg). Results indicate that YC-1 may improve survival due to induce Hsp70 overexpression.European journal of pharmacology 12/2012; DOI:10.1016/j.ejphar.2012.11.044 · 2.68 Impact Factor
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ABSTRACT: In the present study, we investigated possible roles of the zinc (Zn)-binding protein metallothionein-3 (MT3) and cellular Zn in a mouse model of laser-induced choroidal neovascularization (CNV) using wild-type (WT) and MT3-knockout (KO) mice. Quantitative RT-PCR was used for the detection of MT3 mRNA. CNV was induced in mice between 8 and 12 weeks of age by disrupting the Bruch's membrane using an argon laser. Fundus photography and fluorescein angiography (FA) were performed 2 weeks following laser photocoagulation. The possible connection between MT3 and vascular endothelial growth factor (VEGF) expression was explored by quantifying VEGF levels in WT and MT3-KO mouse retinas by enzyme-linked immunosorbent assay. The role of Zn in VEGF expression was tested in WT and MT3-KO cells treated with pyrithione, with or without additional Zn, using immunoblotting and fluorescence photomicrography. Following laser-treatment, MT3-KO mice exhibited substantially smaller areas of CNV compared to WT mice. In addition, retinal angiograms revealed less severe fluorescein leakage in MT3-KO mice than in WT mice. On day 14 following the induction of CNV, VEGF expression was markedly increased in WT mice, but remained unchanged in MT3-KO mice. Consistent with the possible involvement of Zn released from MT3, raising intracellular Zn levels increased VEGF levels and activated its receptor, Flk-1, in both WT and MT3-KO retinal cells. Present results demonstrated that neural retinal cells express high levels of MT3, which might play a role in the process of CNV development. Moreover, Zn released from MT3 may contribute to VEGF induction.Metallomics 08/2013; DOI:10.1039/c3mt00150d · 3.98 Impact Factor
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ABSTRACT: To investigate the effects of curcumin on the development of experimental choroidal neovascularization (CNV) with underlying cellular and molecular mechanisms. C57BL/6N mice were pretreated with intraperitoneal injections of curcumin daily for 3 days prior to laser-induced CNV, and the drug treatments were continued until the end of the study. The CNV area was analyzed by fluorescein-labeled dextran angiography of retinal pigment epithelium (RPE)-choroid flat mounts on day 7 and 14, and CNV leakage was evaluated by fluorescein angiography (FA) on day 14 after laser photocoagulation. The infiltration of F4/80 positive macrophages and GR-1 positive granulocytes were evaluated by immunohistochemistry on RPE-choroid flat mounts on day 3. Their expression in RPE-choroid complex was quantified by real-time PCR (F4/80) and Western blotting (GR-1) on day 3. RPE-choroid levels of vascular endothelial growth factor (VEGF), tumor necrosis factor (TNF)-α, monocyte chemotactic protein (MCP)-1, and intercellular adhesion molecule (ICAM)-1 were examined by ELISA on day 3. Double immunostaining of F4/80 and VEGF was performed on cryo-sections of CNV lesions on day 3. The expression of nuclear factor (NF)-κB and hypoxia-inducible factor (HIF)-1α in the RPE-choroid was determined by Western blotting. Curcumin-treated mice had significantly less CNV area (P<0.05) and CNV leakage (P<0.001) than vehicle-treated mice. Curcumin treatment led to significant inhibition of F4/80 positive macrophages (P<0.05) and GR-1 positive granulocytes infiltration (P<0.05). VEGF mainly expressed in F4/80 positive macrophages in laser injury sites, which was suppressed by curcumin treatment (P<0.01). Curcumin inhibited the RPE-choroid levels of TNF-α (P<0.05), MCP-1 (P<0.05) and ICAM-1 (P<0.05), and suppressed the activation of NF-κB in nuclear extracts (P<0.05) and the activation of HIF-1α (P<0.05). Curcumin treatment led to the suppression of CNV development together with inflammatory and angiogenic processes including NF-κB and HIF-1α activation, the up-regulation of inflammatory and angiogenic cytokines, and infiltrating macrophages and granulocytes. This provides molecular and cellular evidence of the validity of curcumin supplementation as a therapeutic strategy for the suppression of age-related macular degeneration (AMD)-associated CNV.PLoS ONE 12/2012; 7(12):e53329. DOI:10.1371/journal.pone.0053329 · 3.53 Impact Factor