ABSTRACT
Background The rejection following keratoplasty still is a leading cause of corneal transplantation failure.Studies showed that the interleukin-22 (IL-22) ,one of the effector molecules of T helper cell 17 (Th17) participated on the rejection after heart,liver and bone marrow transplantation.However,the effect of IL-22 on corneal graft rejection is not well understood.Objective This study was to investigate the expression of IL-22 mRNA in the corneal grafts and the role of IL-22 in the immune rejection after corneal transplantation in rats.Methods Seventy-two Wistar rats were randomized into autologous keratoplasty group,allograft keratoplasty group and anti-rejection group,and other 4 normal Wistar rats served as normal control group.Autologous keratoplasty was operated on the Wistar rats of the autologous keratoplasty group,and allograft keratoplasty were carried out with the 24 SD rats as donors and 48 Wistar rats as recipients.Tobramycin and dexamethasone eye drops were topically administrated after autologous keratoplasty for 2 weeks in the anti-rejection group.The experimental eyes were examined by slit lamp microscope after surgery and graft survival was evaluated based on the rejection scoring criteria of Larkin.Intergroup accumulated survival rates of grafts were compared using Kaplan-Meier analysis.Histopathological examination of grafts was carried out in 5 and 14 days after operation respectively,and the related expression levels of IL-22 mRNA and aryl hydrocar-bon receptor (AhR) mRNA were carried out by real-time fluorescence quantitative PCR.The feeding and use of the experimental animals followed the Guangdong provincial regulations on the management of experimental animals.The experimental design was approved by the ethics committee of Southern Medical University.Results The median survival time of grafts in the allograft keratoplasty group was 10 days,and that in the anti-rejection group was 17 days,showing a significant survival extention in the anti-rejection group (x2=16.442,P =0.000).Significant differences were found among the 4 groups in the related expression levels of IL-22 mRNA in both 5 days and 14 days after surgery (postoperative 5 days : F=2.44,P =0.00;postoperative 14 days: F=267.92, P =0.00), and the related expression levels of IL-22 mRNA were remarkably higher in the allograft keratoplasty group than those in the anti-rejection group at different time points (postoperative 5 days :9.70±0.35 vs.0.46±0.21;postoperative 14 days : 23.12 ± 1.89 vs.3.14±0.94) (both at P＜0.05).The related expression levels of AhR mRNA in the grafts were considerably different among the 4 groups (postoperative 5 days : F =395.73, P =0.00;postoperative 14 days : F =942.37, P =0.00) , and the expression levels were significantly elevated in the allograft keratoplasty group compared with the anti-rejection group at various time points (postoperative 5 days:2.52±0.32 vs.1.89±0.10;postoperative 14 days:7.20±0.25 vs.2.60±0.17) (both at P＜0.05).Conclusions The expression level of IL-22 RNA up-regulates in the grafts with immuno-rejection.Topical administration of tobramycin and dexamethasone eye drops inhibits the rejection after keratoplasty.AhR plays a regulative role to the expression of IL-22 in rats after keratoplasty.
ABSTRACT
Objective To investigate whether a novel long-acting tumor necrotic factor (TNF) antagonist (soluble TNF receptor:IgG Fc [sTNFR:IgG-Fc]) can protect hepatocyte damage against liver failure caused by drugs in immunity-induced cirrhotic rats.Methods Wistar rats were repeatedly sensitized by human serum albumin (HSA) emulsified in complete freud adjuvant.The blood was collected at day 10 after the final sensitization.If anti-albumin antibody was positive,the rats were intravenously injected with HSA twice a week.After six weeks,liver cirrhosis was induced by immunity.All the model rats were divided into three groups with 15 each.Liver failure was induced with D-galactosamine/ lipopolysaccharide (LPS) intraperitoneal injection in the rats with liver cirrhosis in model group.The rats in pretreatment group were intraperitoneally injected with long-acting soluble TNF receptor p55 18 h before D-galactosamine/LPS injection.The control group were injected with 0.9％ sodium chloride.General condition,survival rate,liver function and pathological changes were all examined.Serum levels of interleukin (IL)-6,IL-22 and intrahepatic level of IL-6 were detected by enzyme linked immunosorbent assay (ELISA).The activity of Caspase 3 in hepatocyte lysis solution was measured by spectrophotography.Real-time polymerase chain reaction (PCR) was used to detect mRNA expressions of proliferating cell nuclear antigen (PCNA),bcl-2,bax and IL-22 receptor.Data were analyzed by variance analysis among groups.Results Rats in model group were dispirited with poor response after 12 hours and only 3 survived,compared with soluble TNF receptor p55 pre-treated group rats,in which all survived (P=0.029 8) with flexible response.Serum alanine aminotransferase levels in these two groups were (6 533± 360) and (105 ± 7) U/L,respectively.Hepatic regenerative nodule developed massive or submassive necrosis with septal fibrosis in model group,whereas soluble TNF receptor p55 alleviated the inflammatory and necrosis reaction of hepatic tissue.Serum IL-6 levels in model group and pretreatment group were (842.0±12.9) and (91.9±1.6) pg/mL,respectively (F=380.30,P＜0.01).Intrahepatic levels of IL-6 in these two groups were (26.2±1.2) and (11.1±0.8) pg/mL,respectively (F=176.90,P＜0.01),and serum IL-22 levels were (167.0±27.8) and (988.0±109.6) pg/mL,respectively (F=37.91,P＜0.01).Hepatic Caspase-3 activity was reduced by almost 60％ by soluble TNF receptor p55 pretreatment (F=303.70,P＜0.01) and bax expression reduced by 22％ (F=108.80,P＜0.01),while bcl-2 and PCNA expressions were up-regulated by 3.6-folds and 23.0-folds,respectively (F=115.60,P＜0.01; F=594.20,P＜0.01).Conclusions Long acting soluble TNF receptor p55 could improve survival rate,liver function and reduce inflammatory reaction of rats with liver failure induced by drugs on the basis of liver cirrhosis caused by immunity,which indicates that this drug may process a potential therapeutic value.
ABSTRACT
Objective To study the anti-oxidative stress effects of benazepril and candesartan.Methods SHRs of 12 weeks old were given benazepril(10 mg/kg?d,n=9)or candesartan(4 mg/kg?d,n=9)or combina- tion(Ben:10 mg/kg?d+Can:4 mg/kg?d)for 12 weeks.The tail arterial pressure was measured every two weeks.At end of study,pathological changes in the thoracic aorta,activity of SOD,serum contents of NO and hydroxy radicals,plasma Ang Ⅱ and cGMP,eNOS and P22~(phox)protein expressions in aortic tunica intima were de- termined.Results The thoracic aorta wall was thickened markedly in SHRs,and blood pressure,hydroxy radi- cal,Ang Ⅱ and P22~(phox)protein expression were increased significantly,while the serum NO,level of cGMP and eNOS expression were decreased.Benazepril(Ben)or Candesartan(Can)inhibit the thickening of vessel wall, enhance the activity of SOD(Ben:68.7?2.1,Can:65.6?4.2 vs SHR:48.8?3.2 U/mL,P