Objective The stimulating factors and etiology of myocyte hypertrophy are not yet clear.We aim to investigate the mechanisms of bone morphogenetic protein 4 (BMP4)-induced H9C2 myocyte hypertrophy in rats by activating the extracellular signal regulating kinase ( ERK1/2) signaling pathway. Methods Rat H9C2 myocytes were cultured, the model of BMP4-induced H9C2 myocyte hypertrophy was established, and the cells were randomly di-vided into control A, BMP4 A, and angiotensinⅡ( AngⅡ) groups to be treated for 48 hours.The changes in the expression of ERK1/2 protein phosphorylation were observed at 0, 10, 30, 60, and 120 min after treated with BMP4 at the concentration of 50 μg/L and at 30 min after treated with BMP4 at 0, 10, 50, and 100 μg/L.The changes of the H9C2 myocytes were also observed after blocking the ERK1/2 signaling pathway.The cells were divided into control B, BMP4 B, BMP4+PD98059, and PD98059 groups to be cultured with 50μg/L BMP4 for another 48 hours after 30 min blockage with PD98059 at 50 ×10 -6 mol/L.The size and area of the cells were measured by inverted microscopy and image J Software, their total protein content detected by BCA, and the expressions of p-ERK1/2 and brain natriuretic peptide ( BNP) determined by Western blot. Results Compared with control A, the BMP4 A, and AngⅡ groups showed markedly larger cell areas ([649.74 ±2.03] vs [744.85 ±1.31] and [748.39 ±1.54] μm2), higher protein contents ([243.18 ±3.69] vs [340.09 ±2.14] and [347.43 ± 3.30] pg/cell), and higher expressions of the BNP protein ([0.72 ±0.44] vs [0.96 ±0.55] and [1.07 ±0.55]/GAPDH), with statistically significant differences between any two groups (P>0.05).After BMP4 intervention, the expression of p-ERK1/2 manifes-ted a time-dependent trend of first going up and then coming down, reaching the peak at 30 min, with the ERK1/2 protein phosphoryl-ation significantly higher at 30 min than at 10 min (P>0.05), especially than at 0, 60, and 120 min (P>0.01).The level of p-ERK1/2 protein phosphorylation in the mytocytes was elevated with the increased concentration of BMP4, remarkably higher at 50μg/L than at 0 and 10μg/L, but lower than at 100μg/L ( P>0.01) .The cell area, protein content, and BNP protein expression of the H9C2 myocytes were significantly lower in the BMP4+PD98059 group ([650.49 ±1.28] μm2, [244.06 ±3.48] pg/cell, and [0.55 ±0.15]/GAPDH) than in the BMP4 B group ([746.04 ±1.45] μm2, [343.57 ±4.11] pg/cell, and [0.79 ±0.55]/GAPDH) (P>0.01). Conclusion BMP4 may induce hypertrophy of rat H9C2 myocytes by activating the ERK1/2 signaling path-way.Early blocking of ERK1/2 activation may contribute to the management of myocardial hypertrophy.

Objective To investigate the relationship between single nucleotide polymorphism (677C→T) of methylenetetrahydrofolate reductase and Alzheimer′s disease(AD) in south China Han people. Methods By applying polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP), MTHFR 677C→T mutation was detected in 45 AD patients and 48 healthy controls. Results The frequency of MTHFR 677C→T mutation of patients showed no significant difference to that of healthy controls (P > 0.05). There is no statistic significance between AD group and controls in C, T gene frequency(P>0.05). But T gene frequency is higher in AD group than in control group. Conclusion MTHFR C 677T is not the pathogenic factor for AD, but could have some effects on AD.

BACKGROUND:Previous studies have shown that kainic acid injected into hippocampus can significantly upregulate the expression of excitatory KA1 subunit of the kainate receptor in the hippocampus, and endoplasmic reticulum stress markers, phosphorylation of the alpha subunit of eukaryotic initiation factor 2, accompanied by celldeath. OBJECTIVE:To explore the mechanism of endoplasmic reticulum stress after kainic acid is injected into the hippocampus.METHODS:0.15 nmol kainic acid was injected into the hippocampal CA1 region of 32 adult male Kunming mice, the injection time was 60 seconds. At different time points (1, 2, 3, 4, 5, 6, 8 and 12 hours) after kainic acid was injected, the Bederson score analysis was performed, and then the brain was harvested after cerebral perfusion. FJB staining of brain sections and immunofluorescence double labeled observation were also performed. RESULTS AND CONCLUSION:(1) At 3, 4, 5, 6, 8 hours after kainic acid injection, Bederson score showed severe injury of central nervous system function, and FJB staining showed the increased of celldeath in the hippocampus (P<0.05);At 1, 2, 12 hours after injection, Bederson score showed no obvious injury of central nervous system function, and FJB staining showed unobvious celldeath in the hippocampus (P>0.05). (2) According to the results of FJB staining, the brain sections were selected at 3, 8 hours for immunohistochemistry. The expressionlevels of KA1 receptors and endoplasmic reticulum stress marker P-eIF2αwere up-regulated at the same time after kainic acid was injected into hippocampus. Two single-staining KA1 and P-eIF2αimmunofluorescence images were synthesized into one over-lapped double-stained image, and two images overlapped, indicating that the up-regulated expression of KA1 and endoplasmic reticulum stress occurred in the same nerve cells. Kainic acid first up-regulated the excitatory receptor KA1 expression, which may cause cellendoplasmic reticulum dysfunction and result in the endoplasmic reticulum stress response, further promoting neuronal celldeath.

OBJECTIVETo study the feasibility of sustaining the viable status of a liver graft in at least 96 h by extracorporeal perfusion using autologous blood.

METHODSEight extracorporeal porcine liver perfusions using autologous blood were performed, each for 96 h with hepatectomy, cold preservation, cannulation of vessels, and initiation of perfusion with normothermic oxygenated porcine blood. The graft viability was assessed by metabolic, synthetic, hemodynamic, and histologic parameters.

RESULTSAfter 96 h of normothermic, extracorporeal perfusion using autologous blood, the isolated livers maintained normal physiological levels of pH and electrolytes with sustained hepatic protein synthesis (complement and factor V) throughout the perfusion. Hemodynamic parameters maintained normal physiological ranges. Histological inspection demonstrated good preservation of the liver with a good architectural integrity.

CONCLUSIONIt is possible to sustain the viable status of a liver graft within 96 h by extracorporeal perfusion using autologous blood.

Animals ; Extracorporeal Circulation ; Liver ; Liver Transplantation ; Organ Preservation ; Organ Preservation Solutions ; Swine

OBJECTIVETo explore the effect of up-regulation of KA1 subunit of the kainate receptor on endoplasmic reticulum stress (ERS)-induced excitotoxic neurodegeneration in mouse hippocampus.

METHODSSeventy adult male KM mice were subjected to microinjections into the hippocampus of kainic acid (KA) or 500, 1000, or 2000 µg/ml tunicamycin (TM). At 1, 2, 3, 4, 5, 8, and 12 h after the injections, the mice were assessed for Bederson scores and sacrificed for FJB staining and immunofluorescence observation of the brain slices.

RESULTSAt 3, 4, 5, and 8 h after KA injection and at 4 and 5 h after of 2000 µg/ml TM injection, the mice showed severe central nervous system dysfunction, and FJB staining revealed increased cell death in the hippocampus, where up-regulated expressions of KA1 receptor and ERS marker P-eIF2α were found by immunofluorescence staining (P<0.05).

CONCLUSIONMicroinjection of KA or TM into the hippocampus causes neuronal death and ERS with up-regulated expression of KA1. In this process of neuronal apoptosis, the membrane receptor KA1 receives the apoptosis signal and transfers it to the inside of the cells to cause cell endoplasmic reticulum dysfunction and ERS response, which ultimately leads to neuronal death.

Animals ; Apoptosis ; Endoplasmic Reticulum Stress ; Hippocampus ; pathology ; Kainic Acid ; pharmacology ; Male ; Mice ; Neurons ; pathology ; Receptors, Kainic Acid ; metabolism ; Tunicamycin ; pharmacology ; Up-Regulation