Molecular mechanism whereby paraoxonase-2 regulates coagulation activation through endothelial tissue factor in rat haemorrhagic shock model.

We investigated the molecular mechanism of paraoxonase-2 (PON-2) in regulating blood coagulation activation in rats with haemorrhagic shock through endothelial tissue factor (TF). Thirty adult Sprague Dawley rats were randomly divided into three groups: healthy control group (group A), the haemorrhagic shock PON-2 treatment group (group B), and the haemorrhagic shock group (group C). After the model was established, blood was withdrawn from the inferior vena cava of all rats. The difference in plasma thrombomodulin (TM) levels of the three groups was determined by Western blotting. The expression of transcription factors Egr-1 and Sp1 was detected by Western blotting assays. reverse transcription-polymerase chain Reaction (RT-PCR) was used to determine the mRNA expression of t-PA, PAI-1, TM, and PON-2 in the serum of three groups of rats. Endothelial TF was measured by enzyme linked immunosorbent assay (ELISA), and coagulation assay was used to detect the activity of coagulation factor VIII. Histopathological examination of the arteries of the rats was performed. The molecular mechanism of PON-2 in regulating blood coagulation activation in haemorrhagic shock model rats by endothelial tissue factor was analysed. The expression of thrombin was determined by electrophoresis. Compared with the healthy control group, the expression of TM in groups B and C decreased, both 188.64 ± 12.47 and 137.48 ± 9.72, respectively, with a significant difference. The mRNA expression of TM and PON was determined by RT-PCR. The mRNA expression of TM and PON in group B was 0.97 ± 0.07 and 1.14 ± 0.09, compared with the control group, and the mRNA expression of TM and PON in group C was 0.86 ± 0.38 and 1.12 ± 0.41, both of which increased, and there were significant differences. By measuring the expression of endothelial TF, the expression of TF in groups B and C was elevated to 12.69 ± 1.07 and 11.59 ± 0.87, with significant differences. The enzyme activities of PON-2 in groups B and C, which were 110.34 ± 14.37 and 52.37 ± 8.06, respectively, were increased compared with the healthy control group and there were significant differences. PON-2 regulates the activation of coagulation in rats with haemorrhagic shock by regulating the expression of endothelial tissue-related genes such as plasma TM and endothelial TF under hypoxic and ischaemic conditions.

Innate immune molecule surfactant protein D attenuates sepsis-induced acute kidney injury through modulating apoptosis and NFκB-mediated inflammation.

The objective of this study is to investigate the mechanism whereby innate immune molecule surfactant protein D (SP-D) attenuates sepsis-induced acute kidney injury (AKI) through modulating apoptosis and nuclear factor kappa-B (NFκB)-mediated inflammation. In the present study, a mouse sepsis model was established by cecal ligation and puncture in SP-D knockout (KO) mice and wild-type (WT) mice. A sham-operated group was included as the control. The experimental materials were extracted 6 and 24 hours postoperatively. The plasma levels of tumour necrosis factor alpha (TNF-α) and MCP-1 were determined by enzyme-linked immunosorbent assay (ELISA). Apoptosis was measured by double staining with Annexin V/propidium iodide and flow cytometry. The levels of NFκB in renal tissues were measured by ELISA and Western blotting assay. Apoptosis was detected by TUNEL assays. There were no significant differences in plasma TNF-α levels between the WT sham group and the KO sham group at 6 and 24 hours postoperatively (P < .05), but the levels of TNF-α in the WT sepsis and KO sepsis groups were significantly higher than those in controls (P < .05). The levels of TNF-α in the KO sepsis group were significantly higher than those of the WT sepsis group (P < .05). TNF-α levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The levels of MCP-1 in the WT sepsis group and the KO sepsis group at 6 and 24 hours postoperatively were significantly higher than those in the control group (P < .05), and MCP-1 levels in the KO sepsis group were significantly higher than those in the WT sepsis group (P < .05). MCP-1 levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The expression of SP-D in WT kidneys was significantly lower at 6 and 24 hours postoperatively (P < .05). The number of TUNEL-positive cells in the kidneys from septic SP-D KO mice was significantly higher (P < .05). The levels of NFκB in septic mice were significantly increased at 6 and 24 hours after induction of sepsis compared with the sham-operated group compared with those of septic SP-D KO mice and WT mice (P < .05). Innate immune molecule SP-D significantly decreased plasma levels of inflammatory cytokines in mice and attenuated sepsis-induced AKI by inhibiting NFκB activity and apoptosis.

Cyanidin-3-O-galactoside and blueberry extracts supplementation improves spatial memory and regulates hippocampal ERK expression in senescence-accelerated mice.

OBJECTIVE: To investigate whether the antioxidation and the regulation on the Extracellular Regulated Protein Kinases (ERK) signaling pathway are involved in the protective effects of blueberry on central nervous system. METHODS: 30 Senescence-accelerated mice prone 8 (SAMP8) mice were divided into three groups and treated with normal diet, blueberry extracts (200 mg/kg•bw/day) and cyaniding-3-O-galactoside (Cy-3-GAL) (50 mg/kg•bw/day) from blueberry for 8 weeks. 10 SAMR1 mice were set as control group. The capacity of spatial memory was assessed by Passive avoidance task and Morris water maze. Histological analyses on hippocampus were completed. Malondialdehyde (MDA) levels, Superoxide Dismutase (SOD) activity and the expression of ERK were detected. RESULTS: Both Cy-3-GAL and blueberry extracts were shown effective functions to relieve cellular injury, improve hippocampal neurons survival and inhibit the pyramidal cell layer damage. Cy-3-GAL and blueberry extracts also increased SOD activity and reduced MDA content in brain tissues and plasma, and increased hippocampal phosphorylated ERK (p-ERK) expression in SAMP8 mice. Further more, the passive avoidance task test showed that both the latency time and the number of errors were improved by Cy-3-GAL treatment, and the Morris Water Maze test showed significant decreases of latency were detected by Cy-3-GAL and blueberry extracts treatment on day 4. CONCLUSION: Blueberry extracts may reverse the declines of cognitive and behavioral function in the ageing process through several pathways, including enhancing the capacity of antioxidation, altering stress signaling. Cy-3-GAL may be an important active ingredient for these biological effects.

[Cytoprotective effect of blueberry extracts against oxidative damage of rat hippocampal neurons induced by H2O2].

OBJECTIVE: To investigate the protective effect of blueberry extract (BE, 25% anthocyanins) against oxidative damage in primary cultures of rat hippocampal neurons induced by H2O2. METHODS: Rat hippocampal neurons were randomly assigned to control group, H2O2 group and BE pretreatment groups, BE at six different doses (0.01, 0.1, 1.0, 10.0, 20.0 and 40 microg/ml) and then exposed to 50 micromol/L H2O2 for twenty-four hours. To selecte the most fittest concentration of BE by testing viability of neurons and activity of LDH. Then MDA concentration, SOD activity and neuronal apoptosis were(checked) measured. RESULTS: (1) Compared with H2O2 group, the hippocampal cell viabilities in the 0.1, 1.0 and 10 microg/ml BE groups were significantly increased from 57.44% to 78.42%, 87.71% and 72.40% separately. The activity of LDH in BE groups at varied concentrations (0.1, 1.0 and 10 microg/ml) was significiantly lower than that in H2O2 group. It was found that 1 microg/ml BE had the furthest protective effect against oxidative damage in primary cultures of rat hippocampal neurons induced by H2O2. (2) The concentration of MDA and the rate of neuronal apoptosis of BE group (1 microg/ml) were much lower than H2O2 group, while SOD activity was much higher. CONCLUSION: Proper dose of BE has remarkable protective effect against oxidative stress in primary cultures of rat hippocampal neurons induced by H2O2, the mechanism may be related to decreasing the neuronal apoptosis and enhancing the antioxidation of hippocampal neurons.