ABSTRACT
Objective The amyloid β-protein precursor contains a domain highly homologous to Kunitz-type serine protease inhibitors. We have successfully established and characterized the recombinant human rhKD/APP in vitro. The aim of this study is to investigate the potential neuroprotective role of rhKD/APP on cerebral ischemia/reperfusion injury in rats. Methods Rats pretreated with rhKD/APP (4, 8, 16 mg/kg) were subjected to prepare models of cerebral ischemia/reperfusion (I/R) injury and those rats treated with Nimodipine were used as positive control. Comparison of the scores of neurological deficits, TTC-stained infarct volume and cerebral water content between the groups was performed. The activities of SOD, Na+-K+-ATPase and the content of MDA in the cortex tissues were measured and the activities of serum myeloperoxidase ( MPO) enzyme were also compared. The expressions of adhesion molecules ( ICAM-1 and E-selectin) were compared by immunohistochemistry. End-labeling of nuclear DNA fragmentation (TUNEL) and qualification of caspase-3, Bcl-2 and Bax were also employed to evaluate the local apoptosis in cortex tissues. Results By pretreatment with the rhKD/APP at three doses, cerebral infarct volume, water content and neurological deficits were all reduced. The activities of SOD, and Na+-K+-ATPase were increased, the contents of MDA were decreased in the cortex tissues, and the serum MPO activity was reduced. The expressions of adhesion molecules were downregulated and the apoptotic signaling of neurons were inhibited. All the changes induced by rhKD/APP treatment in the ischemia/reperfusion injury models showed statistical significance compared with the control rats. However, no significant difference was shown between the rhKD/APP group and Nimodipine group excepted for the reduced MPO in sera. Conclusions The result of this study suggest that rhKD/APP has neuroprotective effect on the cerebral ischemia/reperfusion injury through inhibiting multiple signaling pathways and is promising to be a potential neuroprotective drug.
ABSTRACT
Present study aimed to investigate the eff ect of curcumin-pretreatment on intestinal I/R injury and on intestinal mucosa barrier. Thirty Wistar rats were randomly divided into: sham, I/R, and curcumin groups (n=10). Animals in curcumin group were pretreated with curcumin by gastric gavage (200 mg/kg) for 2 days before I/R. Small intestine tissues were prepared for Haematoxylin & Eosin (H&E) staining. Serum diamine oxidase (DAO) and tumor necrosis factor (TNF)-alpha levels were measured. Expression of intestinal TNF-alpha and tight junction protein (ZO-1) proteins was detected by Western blot and/or immunohistochemistry. Serum DAO level and serum and intestinal TNF-alpha leves were signifi cantly increased after I/R, and the values were markedly reduced by curcumin pretreatment although still higher than that of sham group (p<0.05 or p<0.001). H&E staining showed the significant injury to intestinal mucosa following I/R, and curcumin pretreatment signifi cantly improved the histological structure of intestinal mucosa. I/R insult also induced significantly down-regulated expression of ZO-1, and the eff ect was dramatically attenuated by curcumin-pretreatment. Curcumin may protect the intestine from I/R injury through restoration of the epithelial structure, promotion of the recovery of intestinal permeability, as well as enhancement of ZO-1 protein expression, and this eff ect may be partly attributed to the TNF-alpha related pathway.
Subject(s)
Animals , Amine Oxidase (Copper-Containing) , Blotting, Western , Curcumin , Eosine Yellowish-(YS) , Immunohistochemistry , Intestinal Mucosa , Intestine, Small , Intestines , Permeability , Rats, Wistar , Reperfusion Injury , Tight Junctions , Tumor Necrosis Factor-alpha , Zonula Occludens-1 ProteinABSTRACT
Objective Proteomics changes from the proteserum which isolated from the rat model of renal ischemia/reperfusion(I/R) injury are detected and investigated by the matrix-assisted UV laser desorption ionization time of flight mass sperctra (MALDI-TOF MS). Methods After the establishment of rat renal ischemia-reperfusion model,the serum samples which we selected respectively in 6,12,24 hours after reperfusion in each group were detected by MALDI-TOF MS analysis. And the peptide fingerprint which existed differences in each group were analyzed to identify.SPSS13.0 software was used to the analysis the data. At the same time,we used Mascot Search to determine their nature in protein database. Results ①the serum which was analyzed by IMAC-Cu bead was detected and had statistically significant peptide fingerprint in the m/z 2481 Da.②the results obtained from peptide mass fingerprint (PMF) were analyzed by Mascot search program for protein identification. We identified it as rat fibrinogen fragment.Conclusion Fibrinogen in kidney ischemia/reperfusion (I/R) injury plays an important role.