Objective To investigate the effects and mechanisms of lactic acid bacteria on MAPK signaling in immune response of dust mite sensitized mice. Methods Forty C57BL/6 mice in Group M, P and L, were sensitized and challenged with mite extract while then the animals in Group N were treated with saline as control. The mice in Group L and P were fed with Lactococcus lactis or Lactobacillus respectively.Three days after the last challenge, all mice were sacrificed for lung pathological examination. IL-10 level in culture supernatant of splenocytes stimulated with mite extract was detected by ELISA. The expression of IL-4/ IFN-γon CD3 +CD4 + cells was detected by flow cytometry. Western blot were performed for detection of MAPK signaling ( P38, ERK, and JNK) from mice’s spleen cells stimulated with mite extract. Results The mice fed with Lactococcus lactis ( Group L) had lower rate of eosinophilic airway inflammation and higher level of IL-10 in the culture supernatant of splenocytes than Group P. Meanwhile, the number of CD4 + T cell with IL-4 expression was decreased revealed by the analysis of flow cytometry. P38 signaling inspleen cells was activated in the mice of Group M, similarly in the mice of Group P, but not of Group L.Conclusion Oral treatment of Lactococcus lactis can induce an immune tolerance in response to mite by up-regulating the level of Tr cells secreting IL-10, thus inhibiting activation of P38 signaling.
Objective To investigate the effects of antithrombin-Ⅲ ( AT-Ⅲ) on the inflammatory reaction in oleic acid-induced acute lung injury ( ALI) rats. Methods Sixtymale Sprague-Dawley rats were randomly divided into five groups, ie. a normal control group, an ALI group, an AT-Ⅲ treatment group, an AT-Ⅲ +heparin treatment group, and a heparin treatment group ( n =12) . The ALI rats were induced by injecting oleic acid ( 0. 2 mL/kg) intravenously. The lung histology was scored by modified Smithtechnique. The albumin permeability of pulmonary microvascular ( Palb) was measured by single nuclide tracer technique. The extravascular lung water ( EVLW) and wet/dry weight ratio ( W/D) of lung tissues were measured by gravity way. The activity of AT-Ⅲ in plasma was determined by the method of syntheticchromogenic substrate. Tumor necrosis factor α( TNF-α) , interleukin 6 ( IL-6) and von Willebrand factor ( vWF) levels in serum were determined using commercial enzyme-linked immunosorbent assay kits. The expressions of lung tissue extacellular signal-regulated kinases ( ERK) -1 /2, P38 mitogen-activated proteinkinase ( MAPK) and c-jun N-terminal kinases ( JNK) were determined by Western blot. Results The Smith scores, EVLW, Palb , plasma level of vWF, lung tissue levels of phospho-ERK1 /2 and phospho-P38 MAPK expressions in the ALI group were all significantly higher than those in the normal control group ( P lt; 0.05) , while not significant differentwith other three treatment groups. There were not significant differences in the activity of AT-Ⅲ in plasma and phospho-JNK expression among all five groups. The serum levels of TNF-αand IL-6 in the ALI group were significantly higher than those in the normal control group and three treatment groups. Conclusions AT-Ⅲ downregulates the levels of downstreamcytokines TNF-αand IL-6,but can not inhibite the activation of ERK1 /2 and P38 MAPK, and can not relieve endothelial permeability.The study do not demonstrate the lung protective effect of AT-Ⅲ in oleic acid-induced acute lung injury.
ObjectiveTo observe the effects of angiostatin on the activity of extra-cellular signal-regulated protein kinase (ERK) of retinal microvascular endothelial cells of mice.MethodsAngiostatin was separated and purified by l-lysine sepharose 4B from human plasma. The primary retinal microvascular endothelial cells were divided into 4 groups: the control group, vascular endothelial growth factor (VEGF) 10 ng/ml group, angiostatin 130 μg/ml group, and VEGF (10 ng/ml) + angiostatin (130 μg/ml) group. The expression of ERK1 was assayed by Westernblotting method 1, 2, 5, 10, 15, and 30 minutes after the treatment of angiostatin.ResultsCompared with the control group, the expression of ERK-1 reduced 1 minute after treatment, reduced markedly after 10 minutes. After 30 minutes, no differences of the expression of ERK were seen between the control group and angiostatin group. The activation of ERK-1 of retinal microvascular endothelial cells occurred after stimulated by VEGF, and at the pitch at the peak after 5 minutes. The level of ERK in VEGF group increased 210% than that in the control (P＜0.05). After 30 minutes, no significant difference of the level of ERK between VEGF and the control group. And because of angiostatin, the expression of ERK-1 decreased 11.9%(1 minute)、17.9%(2 minutes)、38.7%(5 minutes)、49.3%(10 minutes) （P＜0.05）、27.9%(15 minutes)、1.12%(30 minutes) respectively.ConclusionsAngiostatin can effectively block the signal path through which VEGF transmits from outside of the cell to cellular nuclei. (Chin J Ocul Fundus Dis, 2005,21:170-173)
【 Abstract 】 Objective To investigate the effects of 250 ml/m3 carbon monoxide (CO) inhalation or intraperitoneal infusion on lipopolysaccharide (LPS) induced rat intestinal tract injury, and to detect the roles of p38 mitogen-activated protein kinase (MAPK) pathway during CO administration. Methods After received 5 mg/kg LPS or an equal volume of normal saline by intravenous injection, 108 male SD rats were randomly divided into 6 groups: control group, CO inhalation (250 ml/m3) group, CO intraperitoneal infusion (250 ml/m3 at a rate of 2 L/min) group, LPS (5 mg/kg) group, LPS (5 mg/kg)+CO inhalation (250 ml/m3) group and LPS (5 mg/kg)+CO intraperitoneal infusion (250 ml/m3 at a rate of 2 L/min) group. The animals were differently sacrificed at 1, 3 and 6 h for the observation, and the ileum tissues were homogenized for determination the levels of platelet activator factor (PAF), intercellular adhesion molecule-1 (ICAM-1) and interlukin-10 (IL-10) with enzyme-lined immunosorbent assay, the content of maleic dialdehyde (MDA) with thiobarbitric acid, the activity of myeloperoxidase (MPO) with chemical method, the activity of superoxide dismutase (SOD) with hydroxylamine, the activity of phosphorylated p38 MAPK with Western blot, the pathology with light microscope, and the extents of cell apoptosis were showed by the ratio of the apoptotic cells which had less DNA to the total cells of a cell-suspension sample by using the flow cytometry after being stained with propidium iodide. Results Compared with both control, CO inhalation and intraperitoneal infusion group at the same time point, the levels of PAF, ICAM-1, MDA, MPO, cell apoptosis rate and the phosphorylated p38 MAPK protein in LPS group were increased, while IL-10 and SOD were decreased (P ＜ 0.05 or 0.01), and accompanied by severe intestinal tract injury. There were no statistics differences at the different time point in the same group. PAF, ICAM-1, MDA, MPO and cell apoptosis rate in both LPS+CO inhalation group and LPS+CO intraperitoneal infusion group were lower, while IL-10 and SOD were higher than the corresponding value in LPS group at the same time point (all P ＜ 0.05), with ameliorate injury too, but the expression of phosphorylated p38 MAPK was further up-regulated than that of LPS group (all P ＜ 0.05). However, there were no significant differences in these parameters between LPS+CO inhalation group and LPS+CO intraperitoneal infusion group. Conclusion 250 ml/m3 CO inhalation and intraperitoneal infusion exerts the similar protection against LPS induced rat intestinal tract injury via anti-oxidant, anti-inflammation, and anti-apoptosis. This may involve the p38 MAPK pathway.
ObjectiveTo investigate whether signal molecule mitogen-activated protein kinases (MAPKs) involves in the process of the mineralization and maturation of rat calvarial osteoblasts promoted by 50 Hz, 0.6 mT pulsed electromagnetic fields. MethodsRat calvarial osteoblasts were obtained by enzyme digestion from the skull of 6 neonatal Wistar rats of SPF level. The primary osteoblasts were treated in 50 Hz and 0.6 mT pulsed electromagnetic fields for 0, 5, 10, 20, 40, 60, and 120 minutes; the protein expression of phosphorylated MAPKs was detected by Western blot. The osteoblasts were randomly divided into group A (control group), group B (low frequency pulse electromagnetic fields treatment group), group C (SB202190 group), and group D (SB202190+low frequency pulse electromagnetic fields treatment group); the alkaline phosphatase (ALP) activities were tested after corresponding treatment for 1, 4, and 7 days. The corresponding treated more than 90% confluenced osteoblasts were cultured under condition of osteogenic induction, then ALP staining and alizarin red staining were carried out at 9 and 12 days respectively. ResultsThe results of Western blot showed that there was no significant changes in the protein expressions of phosphorylated level of extracellular signal-related kinases 1/2 and c-Jun amino N-terminal kinases 1/2 in 50 Hz, 0.6 mT pulsed electromagnetic fields P>0.05), but the phosphorylated level of p38 began to increase at 5 minutes, peaked at 40 minutes, then gradually decreased, and it was significantly higher at 5-120 minutes than at 0 minute (P<0.05). After the activities of p-p38 was inhibited by inhibitor SB202190, the ALP activities, positive colonies and area of ALP and calcified nodules of group B were significantly higher than groups A, C, and D (P<0.05). Conclusionp38 is one of the signal molecules involved in the process of the mineralization and maturation of rat calvarial osteoblasts promoted by 50 Hz, 0.6 mT pulsed electromagnetic fields.
Epilepsy is a disorder of the brain in which sudden abnormal discharges of neurons cause transient dysfunction and is a common disorder of the nervous system. Although most patients experience remission of symptoms with medication, about 20 ~ 30% of patients still have poor outcomes with medication and progress to refractory epilepsy. The etiology of epilepsy is complex and the exact pathogenesis is not yet clear. Current research has explored the pathophysiological mechanisms underlying epileptogenesis, thus providing a basis for identifying potential therapeutic targets for epilepsy and advancing the precision treatment of epilepsy. p38 Mitogen-activated protein kinase (MAPK) signalling pathway is a conserved class of kinases involved in many physiological/pathological processes by regulating intracellular gene expression levels, cell division, differentiation and apoptosis in response to various extracellular stimuli in order to mediate intracellular signalling cascades. The p38 MAPK signalling pathway is one of the subfamilies of MAPK that mediates inflammatory responses, apoptosis, tissue edema and other biological processes involved in the development of central nervous system diseases. The p38 MAPK signalling pathway is now reviewed for its involvement in the development of epilepsy through unused pathways, in order to identify new potential targets for epilepsy treatment and provide clinical precision.