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In this study, the effect of benzo[α]pyrene (BaP) on chaperone-mediated autophagy (CMA) in a simulated hypoxia environment was observed and the relationship to heat shock protein 90 (HSP90) was clarified. With HSP90 inhibitor geldanamycin (GA) and HSP90α silenced, the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α), HSP90, heat shock cognate protein 70 (HSC70), and lysosomal associated protein 2A (LAMP-2A) of A549 cells on hypoxic environment by BaP were tested. Alkaline comet experiment, immunofluorescence γ-H2AX focus experiment, quantitative real-time PCR (qPCR), and Western blot analyses were used to clarify the relationship between the DNA damage of different concentrations of BaP in A549 cells and the mRNA and protein expression of CMA-related factors. The results show that hypoxia can promote the expression of mRNA and protein of CMA-related factors in A549 cells. This study found that BaP has an inhibitory effect on CMA under the hypoxic environment. The inhibition or silencing of HSP90 will enhance the inhibitory effect of BaP on CMA. In a normoxic environment, BaP causes DNA damage and promotes CMA.
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Objective To investigate the expression of interleukin-34 (IL-34) after corneal transplantation in rats and its mechanisms of action in immune rejection.Methods SD rats were used as donors and Wistar rats as the recipients to establish corneal transplantation experimental models.Together 60 Wistar rats were randomly divided into 3 groups according to the random number table methods,and rats in B group was transplantated with autologous cornea,while C and D groups received allogeneic corneal transplantation.Another 10 rats were collected as normal controls (A group).After B,C group was treated with postoperative Tarivid eye drops,D group was treated with TobraDex eye drops postoperatively.The survival rate of corneal grafts and survival analysis were evaluated in the 10 rats from the 4 groups,and then the corneal grafts were taken from the rest of rats at the fourteenth day after the operation for hstopathological,immunohistochemical and RT-PCR examinations.Results Survival analysis showed that immune rejection did not occur in A and B group,and the mean survival time (MST) was (26.00 ± 0.97) days in D group,which was much higher than that in group C[(10 ± 1.55) days] (P ＜0.001).HE staining showed that there was obvious inflammatory cell infiltration and neovascularization in the corneal tissue of C group,and there were only a few inflammatory cells and neovascularization in D group.Immunohistochemistry showed that IL-34 protein expression in C group (0.089 4 ± 0.005 6) was significantly higher than that of A group (0.037 7 ± 0.002 3),B group (0.068 4 ±0.004 4) and group D (0.044 5 ± 0.004 5) (F =145.21,P ＜ 0.01),and its expression was mainly located in the epithelial and stromal layer.RT-PCR showed that the expression levels of IL-34,IL-1β,IL-17A,TNF-α mRNA in corneal tissue of C group were significantly higher than those in A,B and D group (all P ＜ 0.05).Conclusion IL-34 may involve in the rejection after corneal transplantation in rats,and TobraDex eye drops can delay the rejection by inhibiting the expression of IL-34 and related signaling pathways.
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<p><b>OBJECTIVE</b>To examine expression of stromal cell-derived factor-1 (SDF-1) and CXC chemokine receptor 4 (CXCR4) in rat cornea tissue and their role in corneal allograft rejection.</p><p><b>METHODS</b>With 15 Wistar rats as the normal control group, 22 Wistar rats received autologous corneal graft transplantation, and 44 Wistar rats received transplantation of corneal graft from SD rats with penetrating keratoplasty. From the rats with allograft transplantation, 22 were selected randomly for treatment with TobraDex eye drops for 30 days after the operation (twice a day), and the remaining 22 rats were treated with normal saline only. Clinical assessment of the corneal grafts was carried out using Larkin's method; histopathological observation, immunohistochemistry, and real-time quantitative PCR of the corneal grafts were performed on days 5 and 9 after the transplantation.</p><p><b>RESULTS</b>Graft rejection occurred in none of the rats in autograft group. In rats treated with TobraDex, the graft survival time was significantly longer than that in rats with saline treatment (24∓0.32 vs 10∓0.36 days, P<0.001), and histopathological examination revealed numerous inflammatory cells and neovascularization in the allografts in the latter group. SDF-1 and CXCR4 mRNA expression in the corneal tissue increased significantly in rats receiving allograft transplantation and saline treatment (P<0.001 on day 5 and P<0.01 on day 5), and their expression was obviously lowered in rats with TobraDex treatment. Immunohistochemical examination revealed that the expression of SDF-1 and CXCR4, found mainly in the corneal epithelium and stroma, was significantly increased in the allografts in rats with saline treatment.</p><p><b>CONCLUSION</b>SDF-1/CXCR4 may participate in corneal graft rejection in rats early after transplantation possibly through the mechanism that SDF-1 specifically induces CXCR4cell maturation and chemotaxis toward the allograft to promote corneal neovascularization.</p>
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Objective: To evaluate color velocity imaging-quantitative method (CVI-Q) in estimating cerebral hemodynamic change in patients with cerebral infarction. Methods: The carotids of 60 normal people and 40 cerebral infarction patients were detected by CVI-Q. We observed endangium thickness and atheromatous plaques,and measured the diameter (d), peak velocity(Vmax), resistance index(RI) and blood flow volume(Q) of the common carotid arteries. Results: In cerebral infarction group there were 75% cases with endangium thickening to different degrees, 45% cases with atheromatous plaques and 71% plaques in carotid enlargement section or bifurcation. The data measured in 2 groups were compared: (1)The d value in cerebral infarction cases increased than that in normal（P<0.05 or P<0.01）; (2)The Vmax reduced in cerebral infarction cases(P<0.05); (3)The RI increased in cerebral infarction cases (P<0.05 or P< 0.01); (4) The Q value reduced in cerebral infarction cases (P<0.01). Conclusion: CVI-Q can be used for detecting cerebral hemodynamic changes and provide quantitative indexes for clinicians to estimate ischemia degree and treatment in cerebral infarction patients.
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Objective: To evaluate color velocity imaging-quantitative method (CVI-Q) in estimating cerebral hemodynamic change in patients with cerebral infarction. Methods: The carotids of 60 normal people and 40 cerebral infarction patients were detected by CVI-Q. We observed endangium thickness and atheromatous plaques,and measured the diameter (d), peak velocity(Vmax), resistance index(RI) and blood flow volume(Q) of the common carotid arteries. Results: In cerebral infarction group there were 75% cases with endangium thickening to different degrees, 45% cases with atheromatous plaques and 71% plaques in carotid enlargement section or bifurcation. The data measured in 2 groups were compared: (1)The d value in cerebral infarction cases increased than that in normal（P<0.05 or P<0.01）; (2)The Vmax reduced in cerebral infarction cases(P<0.05); (3)The RI increased in cerebral infarction cases (P<0.05 or P< 0.01); (4) The Q value reduced in cerebral infarction cases (P<0.01). Conclusion: CVI-Q can be used for detecting cerebral hemodynamic changes and provide quantitative indexes for clinicians to estimate ischemia degree and treatment in cerebral infarction patients.