The effects of low-doses of microcystin-leucinearginine （ MC-LR ） exposure on neurobehaviors and N-acetylaspartate （NAA） expression in the hippocampus of rats were investigated. After male Sprague-Dawley （SD） ra...The effects of low-doses of microcystin-leucinearginine （ MC-LR ） exposure on neurobehaviors and N-acetylaspartate （NAA） expression in the hippocampus of rats were investigated. After male Sprague-Dawley （SD） rats were treated intra-gastrically with different doses of MC-LR for 90 d, the locomotor activity, spatial learning and memory function were evaluated in the rats after treatment using open field tests and Morris water maze tests. The results show that MC-LR exposure can lead to impairment of the spatial learning capacity and locomotor activity in rats at the dose of 2. 00 p,g/kg. The levels of NAA in the hippocampus were measured by magnetic resonance spectroscopy （MRI）. A significant decrease of NAA/Cr ratio （ P 〈 0. 05） was observed in the hippocampous. This study indicates that intra-gastrical exposure to low-doses of MC-LR has adverse effects on neuronal behavior and NAA levels in the hippocampous.展开更多
AIM:To investigate the preventive effect of N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) on bile duct ligation (BDL)induced liver fibrosis in rats. METHODS:Liver fibrosis in rats was induced by BDL and AcSDKP was in...AIM:To investigate the preventive effect of N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) on bile duct ligation (BDL)induced liver fibrosis in rats. METHODS:Liver fibrosis in rats was induced by BDL and AcSDKP was infused subcutaneously for 2 wkvia a osmotic minipump (Alzet 2ML4) immediately after BDL operation. After scarifying, serum and liver specimens were collected. Hematoxylin and eosin staining, Sirius red staining, enzyme linked immunosorbent assay, Western blot or real-time polymerase chain reaction were used to determinate liver functions, histological alterations, collagen deposition, mRNA expression of markers for fibroblasts, transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-7 (BMP-7). RESULTS:When compared to model rats, chronic exogenous AcSDKP infusion suppressed profibrogenicTGF-β1 signaling, α-smooth muscle actin positivity (α-SMA), fibroblast specific protein-1 (FSP-1) staining and collagen gene expression. Col Ⅰ, Col Ⅲ, matrix metalloproteinase-2, tissue inhibitors of metallopro-teinase-1 and tissue inhibitors of metalloproteinase-2 mRNA expressions were all significantly downregulated by AcSDKP infusion (2.02 ± 1.10vs 14.16 ± 6.50, 2.02 ± 0.45vs 10.00 ± 3.35, 2.91 ± 0.30vs 7.83 ± 1.10, 4.64 ± 1.25 vs 18.52 ± 7.61, 0.46 ± 0.16 vs 0.34 ± 0.12, respectively, P < 0.05). Chronic exogenous AcSDKP infusion attenuated BDL-induced liver injury, inflammation and fibrosis. BDL caused a remarkable increase in alanine transaminase, aspartate transaminase, total bilirubin, and prothrombin time, all of which were reduced by AcSDKP infusion. Mast cells, collagen accumulation, α-SMA, TGF-β1, FSP-1 and BMP-7 increased. The histological appearance of liver specimens was also improved. CONCLUSION:Infusion of exogenous AcSDKP attenu-ated BDL-induced fibrosis in the rat liver. Preservation of AcSDKP may be a useful therapeutic approach in the management of liver fibrosis.展开更多
基金The National Natural Science Foundation of China(No.8107225881273123)
文摘The effects of low-doses of microcystin-leucinearginine （ MC-LR ） exposure on neurobehaviors and N-acetylaspartate （NAA） expression in the hippocampus of rats were investigated. After male Sprague-Dawley （SD） rats were treated intra-gastrically with different doses of MC-LR for 90 d, the locomotor activity, spatial learning and memory function were evaluated in the rats after treatment using open field tests and Morris water maze tests. The results show that MC-LR exposure can lead to impairment of the spatial learning capacity and locomotor activity in rats at the dose of 2. 00 p,g/kg. The levels of NAA in the hippocampus were measured by magnetic resonance spectroscopy （MRI）. A significant decrease of NAA/Cr ratio （ P 〈 0. 05） was observed in the hippocampous. This study indicates that intra-gastrical exposure to low-doses of MC-LR has adverse effects on neuronal behavior and NAA levels in the hippocampous.
基金Supported by Grants from National Natural Science Foundation of China, No. 30971263 and No. 81170410 (to Chen YW)Shanghai Pujiang Program, No. 10PJ1407600 (to Chen YW)
文摘AIM:To investigate the preventive effect of N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) on bile duct ligation (BDL)induced liver fibrosis in rats. METHODS:Liver fibrosis in rats was induced by BDL and AcSDKP was infused subcutaneously for 2 wkvia a osmotic minipump (Alzet 2ML4) immediately after BDL operation. After scarifying, serum and liver specimens were collected. Hematoxylin and eosin staining, Sirius red staining, enzyme linked immunosorbent assay, Western blot or real-time polymerase chain reaction were used to determinate liver functions, histological alterations, collagen deposition, mRNA expression of markers for fibroblasts, transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-7 (BMP-7). RESULTS:When compared to model rats, chronic exogenous AcSDKP infusion suppressed profibrogenicTGF-β1 signaling, α-smooth muscle actin positivity (α-SMA), fibroblast specific protein-1 (FSP-1) staining and collagen gene expression. Col Ⅰ, Col Ⅲ, matrix metalloproteinase-2, tissue inhibitors of metallopro-teinase-1 and tissue inhibitors of metalloproteinase-2 mRNA expressions were all significantly downregulated by AcSDKP infusion (2.02 ± 1.10vs 14.16 ± 6.50, 2.02 ± 0.45vs 10.00 ± 3.35, 2.91 ± 0.30vs 7.83 ± 1.10, 4.64 ± 1.25 vs 18.52 ± 7.61, 0.46 ± 0.16 vs 0.34 ± 0.12, respectively, P < 0.05). Chronic exogenous AcSDKP infusion attenuated BDL-induced liver injury, inflammation and fibrosis. BDL caused a remarkable increase in alanine transaminase, aspartate transaminase, total bilirubin, and prothrombin time, all of which were reduced by AcSDKP infusion. Mast cells, collagen accumulation, α-SMA, TGF-β1, FSP-1 and BMP-7 increased. The histological appearance of liver specimens was also improved. CONCLUSION:Infusion of exogenous AcSDKP attenu-ated BDL-induced fibrosis in the rat liver. Preservation of AcSDKP may be a useful therapeutic approach in the management of liver fibrosis.
