TRAF6/ERK/p38 pathway is involved in interleukin-17-mediated autophagy to promote osteoclast precursor cell differentiation / 浙江大学学报·医学版

To investigate the effects of interleukin (IL)-17-mediated autophagy on the TNF receptor associated factor (TRAF6)/extracellular signal-regulated kinase (ERK)/p38 pathway and osteoclast differentiation. Mouse bone marrow-derived macrophages (BMM) were cultured with a medium containing 30 ng/mL macrophage colony stimulating factor and 50 ng/mL receptor activator of nuclear factor-kappa B ligard (RANKL), and IL-17 (0.01, 0.1, 1.0, 10 ng/mL) was added for intervention (IL-17 group). Tartrate-resistant acid phosphatase (TRAP) staining was used to observe TRAP positive multinucleated cells; phalloidin fluorescent staining was used to detect actin ring circumference; toluidine blue staining was used to analyze bone resorption lacuna formation. To further examine the mechanism of the effect of IL-17-mediated autophagy on the differentiation of osteoclasts, the control group used RANKL medium to culture mouse macrophage RAW264.7 cells, while the IL-17 group was treated with IL-17 (0.01, 0.1, 1.0, /mL). Western blot was used to detect the expression of autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3) and osteoclast-related proteins c-fos and nuclear factor of activated T cell 1 (NFATc1) after treatment with different concentrations of IL-17. The expression of LC3, NFATc1, TRAF6/ERK/p38 signaling pathway related proteins were detected in IL-17 and autophagy inhibitor 3-MA group. The number of TRAP positive multinucleated cells, the circumference of the actin ring and the area of bone resorption lacuna in IL-17 group treated with IL-17 (0.01, 0.1, were significantly higher than those in the control group. In IL-17 treated RAW264.7 cells, the expression of c-fos, NFATc1, Beclin-1, LC3, TRAF6, p-ERK, and p-p38 was all significantly up-regulated (all 0.05). After treatment with the autophagy inhibitor 3-MA, the expression levels of LC3, NFATc1, TRAF6, p-ERK, and p-p38 all decreased significantly (all 0.05). IL-17 can promote the expression of autophagy proteins and enhance the differentiation ability of osteoclast precursor cells, and the TRAF6/ERK/p38 signaling pathway may be involved in this process.

Propofol combined with hypoxia induces cognitive dysfunction in immature rats p38 pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of propofol combined with hypoxia on cognitive function of immature rats and the possible role of p38 pathway and tau protein in mediating such effects.@*METHODS@#Ninety 7-day-old (P7) SD rats were randomized for daily intraperitoneal injection of propofol (50 mg/kg) or lipid emulsion (5.0 mL/kg) for 7 consecutive days. After each injection, the rats were placed in a warm box (38 ℃) with an oxygen concentration of 18% (hypoxia), 21% (normal air), or 50% (oxygen) until full recovery of the righting reflex. Another 90 P7 rats were similarly grouped and received intraperitoneal injections of p-p38 blocker (15 mg/kg) 30 min before the same treaments. The phosphorylated tau protein, total tau protein and p-p38 content in the hippocampus were detected using Western blotting. The spatial learning and memory abilities of the rats were evaluated with Morris water maze test.@*RESULTS@#Compared with lipid emulsion, propofol injection resulted in significantly increased levels of p-p38, phosphorylated tau and total tau proteins in rats with subsequent hypoxic or normal air treatment ( < 0.05), but propofol with oxygen and injections of the blocker before propofol did not cause significant changes in the proteins. Without subsequent oxygenation, the rats receiving injections of propofol, with and without prior blocker injection, all showed significantly prolonged latency time and reduced platform-crossing times and third quadrant residence time compared with the corresponding lipid emulsion groups ( < 0.05). With oxygen treatment, the rats in propofoland blocker-treated groups showed no significant difference in the performance in Morris water maze test from the corresponding lipid emulsion group. The results of Morris water maze test differed significantly between blocker-propofol group and propofol groups irrespective of exposures to different oxygen levels ( < 0.05), but not between the lipid emulsion and blocker group pairs with exposures to different oxygen levels.@*CONCLUSIONS@#Propofol combined with hypoxia can affect the expression of tau protein through p38 pathway to impair the cognitive function of immature rats, in which oxygen plays a protective role.

Taurine affects expression of ICAM-1, VCAM-1 by p38 pathway in hypoxic endothelial cells / 中国中药杂志

To investigate the effect of taurine(Tau) on ICAM-1, VCAM-1 by p-p38 pathway in bovine pulmonary artery endothelial cells(PAECs) and explore its mechanism of action. Generation 4-12 cells in primary cultures of PAECs were used in experiments and divided into five groups： control group, hypoxia(hyp) group, inhibitor(SB203580) group, treatment(Tau) group, and treatment+inhibitor(SB+Tau) group. The concentration of Tau：100 mmol•L⁻¹; p38 inhibitor SB203580： 20 μmol•L⁻¹; and the treatment time was 12 h. MTT assay was used to detect the inhibitory effect of different concentrations of Tau on PAECs. Western blot and Real-time PCR method were used to detect the p38 pathway proteins and ICAM-1, VCAM-1 expression levels. Immunofluorescence was used to investigate p38 nuclear displacement situation. The results of MTT showed that the inhibitory effect was gradually increased with increasing concentrations of Tau. Western blot and RT-PCR revealed that the protein and mRNA expression levels of ICAM-1, VCAM-1 were reduced by Tau. Western blot and immunofluorescence showed Tau can inhibit p38 activation. Tau may decrease the expression levels of VCAM-1 and ICAM-1 in endothelial cells induced by hypoxia through MAPK p38 pathway.

Anticancer property of berberine in human colorectal adenocarcinoma / 中草药

Objective: To illustrate the anticancer property induced by berberine, which is extracted from Chinese medicine Coptidis Rhizoma. Methods: Human colorectal adenocarcinoma cells, HCT-15, were treated with different concentration of berberine. Cells were then observed under the optical microscope to analyze the morphological changes; CCK-8 assay was used to detect the inhibition of cell proliferation of HCT-15; Immunoblotting was used to detect the changes of autophagy and apoptosis related markers. Athymic mice injected with HCT-15 cells were used to detect the pharmacological activity of berberine in vivo. Results: After berberine treatment, with the increased dose of berberine, the cell number reduced, cell spacing increased, and cell shape shrunk. The IC50 for berberine treatment in HCT-15 cell was 50 μmol/L. Autophagy and apoptosis markers were enhanced after treatment of 0, 50, and 100 μmol/L of berberine. The data further showed that enhanced autophagy and apoptosis were the main contributors for inhibiting cell proliferation. Immunoblotting analysis showed that berberine induced HCT-15 cells to autophagy and apoptosis mainly through p38 pathway. Athymic mice study showed that berberine treatment could decrease the volume of tumor in vivo, and the tumor inhibitory rates by berberine at 0, 50, and 100 mg/kg were 0, 32% and 74%, respectively. Conclusion: Berberine inhibits the HCT-15 cell proliferation, mainly by p38 pathway and enhances autophagy and apoptosis. Berberine can effectively inhibit tumor growth in vivo.

Effects of Dihuangyinzi on behaviors and RAGE/p38 pathway in APP/PS1 mice / 中华行为医学与脑科学杂志

Objective To investigate the effects of Dihuangyinzi(DHYZ) on behaviors and RAGE/p38 pathway in APP/PS1 mice.MethodTwenty APP/PS1 dementia mice were randomly divided into model group(n=10) and Chinese medicine group(n=10).The blank group was C57 BL/6 J normal mouse(n=10).The mice in Chinese medicine group were intragastric administration with DHYZ (9.75 g·kg-1·d-1).The mice in model group and blank group were treated with distilled water.After 30 days,the abilities of learning and memory of mice were detected by Morris water maze.The expression of amyloid-beta1-42(Aβ1-42) in the hippocampus and cortex was detected by immunohistochemistry.Reactive oxygen species of brain tissue were detected by DCFH-DA Methods in the brain of APP/PS1 mice.Gene expression level of receptor for advanced glycation end products(RAGE) was measured by real-time polymerase chain reaction (RT-PCR) in the cortex and hippocampus of APP/PS1 mice.The expression of phospho-mitogen-activated protein kinases (p38) was analyzed with Western blot and immunofluorescence analysis in the cortex and hippocampus of APP/PS1 mice.Results Behavioral Results showed that DHYZ significantly increased the distance((23.088±7.083)cm) and residence time((1.961±1.230)s)of effective area in Morris water maze on the fifth day(P<0.05,P<0.01)and remarkably increased the number of effective area crossings((1.607±0.405) times) and plats((0.893±0.283) times) in Morris water maze on the fifth day(P<0.01,P<0.05).DHYZ also significantly reduced the intracelluar ROS level(122.611±7.630) in the brain(P<0.01),and DHYZ could depress the expression of RAGE(1.467±0.081,7.983±0.136) and phosphorylation of p38 (0.376±0.026,0.538±0.016)in the cortex and hippocampus of APP/PS1 mice(P<0.01,P<0.05).Conclusions The Results demonstrate that DHYZ can partly improve memory impairment of APP/PS1 mice by the inhibition of RAGE/p38 pathway.

Research progress of mitogen-activated protein kinase signaling pathways in leukemia / 白血病·淋巴瘤

Mitogen-activated protein kinase (MAPK) signaling pathways may be involved in various activities of cells such as apoptosis,differentiation and autophagy.In human cells,MAPK signaling pathways mainly contain Erk,p38 MAPK and JNK,and each of them is highly specific and has its own function.MAPK signaling pathways are closely related to the development of leukemia.The effect of MAPK signaling pathways on leukemia cells is mainly mediated by affecting cell apoptosis,cell drug resistant,cell autophagy and differentiation.In this review,recent advances on the study of MAPK in leukemia are reviewed.

MOLECULAR MECHANISMS OF ESTROGEN INDUCED APOPTOSIS OF SYNTHETIC VASCULAR SMOOTH MUSCLE CELLS: p38 PATHWAY-DEPENDENT UP-REGULATION OF MYOCYTE ENHANCER FACTOR 2 / 解剖学报

Objective To explore the underlying molecular mechanisms of estrogen induced apoptosis of synthetic vascular smooth muscle cells (VSMCs). Methods Cultured VSMCs on passage 3 were divided into three groups: 17?-estradiol (E-2) group, p38 inhibitor group (SB+E-2) and control group. With treatment for 72 hours,the apoptosis of cells was quantified by measuring the intracellular nucleosomes with ELISA; expressions of total p38, phospho-p38 and myocyte enhancer factor-2 (MEF2) were analyzed by Western blotting, with a confirmative immunohistochemical staining for MEF2. Results Compared with that of control cells, the rate of apoptosis in VSMCs grown in E-2 was significantly increased, with up-regulations of total p38, phospho-p38 and MEF2. These effects of E-2 were blocked in SB+E-2 group in which the rate of cell apoptosis and expression of p38 had no obvious change compared with that of control group, while the expression of p-p38 and MEF2 was decreased. Immunohistochemical staining showed that MEF2 was mainly located in cellular nucleus, and its expression was increased in E-2 group but decreased in SB+E-2 group. Conclusion Estrogen may induce apoptosis of synthetic VSMCs through p38 pathway-dependent up-regulation of MEF2.