Propofol promotes osteoclastic bone resorption by increasing DC-STAMP expression

BACKGROUND: Propofol is an intravenous anesthetic which has antioxidant effects due to its similarity in molecular structure to α-tocopherol. It has been reported that α-tocopherol increases osteoclast fusion and bone resorption. Here, we investigated the effects of propofol on signaling pathways of osteoclastogenic gene expression, as well as osteoclastogenesis and bone resorption using bone marrow-derived macrophages (BMMs). METHODS: BMMs were cultured with macrophage colony-stimulating factor (M-CSF) alone or M-CSF plus receptor activator of nuclear factor kappa B ligand (RANKL) in the presence of propofol (0–50 µM) for 4 days. Mature osteoclasts were stained for tartrate-resistant acid phosphatase (TRAP) and the numbers of TRAP-positive multinucleated osteoclasts were counted. To examine the resorption activities of osteoclasts, a bone resorption assay was performed. To identify the mechanism of action of propofol on the formation of multinucleated osteoclasts, we focused on dendritic cell-specific transmembrane protein (DC-STAMP), a protein essential for pre-osteoclastic cell fusion. RESULTS: Propofol increased the formation of TRAP-positive multinucleated osteoclasts. In addition, the bone resorption assay revealed that propofol increased the bone resorption area on dentin discs. The mRNA expression of DC-STAMP was upregulated most strongly in the presence of both RANKL and propofol. However, SB203580, a p38 inhibitor, significantly suppressed the propofol/RANKL-induced increase in mRNA expression of DC-STAMP. CONCLUSION: We have demonstrated that propofol enhances osteoclast differentiation and maturation, and subsequently increases bone resorption. Additionally, we identified the regulatory pathway underlying osteoclast cell-cell fusion, which was enhanced by propofol through p38-mediated DC-STAMP expression.

Molecular Cloning and Characterization of a P38-Like Mitogen-Activated Protein Kinase from Echinococcus granulosus

Cystic echinococcosis (CE) treatment urgently requires a novel drug. The p38 mitogen-activated protein kinases (MAPKs) are a family of Ser/Thr protein kinases, but still have to be characterized in Echinococcus granulosus. We identified a 1,107 bp cDNA encoding a 368 amino acid MAPK protein (Egp38) in E. granulosus. Egp38 exhibits 2 distinguishing features of p38-like kinases: a highly conserved T-X-Y motif and an activation loop segment. Structural homology modeling indicated a conserved structure among Egp38, EmMPK2, and H. sapiens p38α, implying a common binding mechanism for the ligand domain and downstream signal transduction processing similar to that described for p38α. Egp38 and its phosphorylated form are expressed in the E. granulosus larval stages vesicle and protoscolices during intermediate host infection of an intermediate host. Treatment of in vitro cultivated protoscolices with the p38-MAPK inhibitor ML3403 effectively suppressed Egp38 activity and led to significant protoscolices death within 5 days. Treatment of in vitro-cultivated protoscolices with TGF-β1 effectively induced Egp38 phosphorylation. In summary, the MAPK, Egp38, was identified in E. granulosus, as an anti-CE drug target and participates in the interplay between the host and E. granulosus via human TGF-β1.

IL-1beta Induces Lysozyme Overexpression through a Mechanism Involving ERK/p38 Mitogen Activated Protein Kinase Activation in Human Airway Epithelial Cells

BACKGROUND AND OBJECTIVES: Lysozyme, a major serous component of airway epithelial secretions, plays an important role in airway defense. However, little is understood about the regulation of its expression and the associated signaling pathway. The object of this study is to investigate the regulation of lysozyme expression, the downstream signaling pathway of lysozyme expression, and the related protein kinases under inflammatory conditions using the IL-1beta, which acts as a significant cytokine in many airway inflammations. MATERIALS AND METHODS: After the IL-1beta treatment of normal human nasal epithelial cells (NHNE), lysozyme mRNA expression was determined by RT-PCR. Expressed levels of ERK/p38 kinase were determined by Western blot analysis. RESULTS: IL-1beta treated NHNEcells had over-expressed lysozyme compared to the control group. Activated ERK/p38 kinase level showed marked increment by treating NHNE with IL-1beta. Lysozyme expression and ERK/p38 kinase levels decreased when inhibitors of ERK/p38 MAP kinases were added to the IL-1beta treated cells. Finally, expression of lysozyme and activated level of ERK/p38 MAP kinases decreased in a dominant-negative cell line even when treated with IL-1beta. CONCLUSION: From these results, we concluded that IL-1beta induces over-expression of lysozyme via ERK/p38 MAP kinase signaling pathways in airway epithelial cells.

The role of p38 MAP kinase on RANKL regulation in mouse periodontal ligament fibroblasts / 대한치주과학회지

No abstract available.

Saponins from Anemarrhena asphodeloides Bge. protect neurons from amyloid β-protein fragment 25-35-induced apoptosis / 中国药理学与毒理学杂志

AIM To investigate the neuroprotective effects and possible mechanisms of saponins from Anemarrhena asphodeloides Bge. (SAaB) on neuronal damage induced by amyloid β-protein fragments 25-35 (Aβ25-35). METHODS Cultured mouse peritoneal macrophages were stimulated with Aβ25-35 (20 μmol·L-1) for 0.5, 1, 2 and 6 h or preincubated with SAaB (10, 30 and 100 μmol·L-1)for 10 min or mitogen-activated protein kinase (MAPK) specific inhibitors (p38 MAPK inhibitor SB 203580 and MEK specific inhibitor PD98059) for 30 min prior to the addition of Aβ25-35(20 μmol·L-1). After stimulation with Aβ25-35 for the indicated times, total cellular extracts were prepared for Western blotting of extracellular signal-regulated kinase (ERK) and p38 MAPK. After stimulation with Aβ25-35 for 48 h, the supernatants of cultured macrophages were collected for quantification of tumor necrosis factor-α (TNF-α) and nitric oxide (NO) and protein expression of inducible nitric oxide synthase (iNOS) in macrophages was determined by immunocytochemical staining. To determine whether SAaB has protective effect against neuronal apoptosis mediated by Aβ25-35-induced macrophages activation, macrophages were stimulated with Aβ25-35 in the presence or absence of SAaB (10, 30 and 100 μmol·L-1) for 48 h and then the cell-free supernatant of Aβ25-35-stimulated macrophages was transferred to the culture of cerebellar granule neurons for 72 h. Neuronal apoptosis was quantitated by scoring the percentage of cells with apoptotic nuclear morphology after Hoechst 33258 staining. RESULTS Aβ25-35(20 μmol·L-1) significantly induced increase in phospho-ERK1/2 and phospho-p38 MAPK protein expression without affecting total protein levels and in the production of TNF-α and NO in cultured macrophages. Aβ25-35-induced increase of TNF-α production in macrophages involved activation of ERK1/2 signal pathway. Importantly, TNF-α and NO generated by cultured macrophages after Aβ25-35 stimulation may be responsible for the majority of the neuronal apoptosis. SAaB (30 and 100 μmol·L-1) significantly suppressed Aβ25-35-induced increase in phospho-ERK1/2 and phospho-p38 MAPK protein. In addition, SAaB (10, 30 and 100 μmol·L-1) also decreased the level of TNF-α and NO in supernatants of cultured macrophage and inhibited Aβ25-35-induced increase in iNOS protein expression of macrophages. Neuronal apoptosis mediated by Aβ25-35-induced macrophage activation was also significantly attenuated by treatment with SAaB (10, 30 and 100 μmol·L-1). CONCLUSION SAaB protects neurons against the neuronal cell death induced by Aβ25-35. The beneficial effects of SAaB may be related to the reduction of TNF-α and NO from activated macrophage induced by Aβ25-35.

MAP kinase superfamily in amyloid β-protein fragment 25-35-induced inflammation andapoptosis in rat hippocampus in vivo / 中国药理学与毒理学杂志

AIM To explore the mechanism of amyloid β-protein fragment 25-35(Aβ25-35)-induced inflammation and apoptosis in rat hippocampus in vivo by studying mitogen-activated protein kinase (MAPK) signaling pathway and the protective effect of anti-inflammatory drug ibuprofen. METHODS Rats were given ibuprofen (7.5 mg·kg-1 daily, ig) for 3 weeks prior to and 1 week after icv single dose of Aβ25-35 (10 μL, 1 mmol·L-1). Seven days after injection, Nissl staining and immunocytochemical technique were employed to determine the morphology of pyramidal neurons and astrocyte infiltration in hippocampal CA1. The expressions of IL-1β, extracellular signal-regulated kinase (ERK), p38 MAPK, PKC, and caspase-3 were determined by Western blot. Reverse transcription-PCR analysis showed changes in IL-1β mRNA level. RESULTS Intracerebroventricular injection of Aβ25-35 elicited astrocyte activation and infiltration and caused a strong inflammatory reaction characterized by increased IL-1β production and elevated IL-1β mRNA level. The inflammatory reaction was accompanied by the loss of pyramidal neurons in hippocampal CA1. The phosphorylation of p38 MAPK was significantly increased, on the other hand, the phosphorylation of ERK was significantly reduced and these were coupled with the increase of caspase-3 expression in hippocampal CA1. Ibuprofen (7.5 mg·kg-1 daily, 4 weeks) significantly reduced Aβ-induced IL-1β expression, caspase-3 expression and p38 MAPK activation. The loss of pyramidal neurons was also significantly attenuated by treatment with ibuprofen. CONCLUSION The activation of p38 MAPK and the down-regulation of ERK play a pivotal role in the inflam-matory response and apoptosis evoked by Aβ25-35 in vivo, which can be prevented by ibuprofen.

Insulin-dependent Stimulation of a Subtype of p38Map Kinases and Its Role in Insulin's Antiapoptotic Activity / 대한내분비학회지

BACKGROUND: The p38 mitogen-activated protein kinases (p38Map kinases) are a family of prolinedirected serine/threonine kinases. At least four isoforms of p38Map kinases have been identified; however, their physiological significances remain to be understood. Recently, the role of p38Map kinase in insulin-stimulated glucose uptake has been suggested. The present study aimed to investigate which isoform(s) were responsive to insulin stimulation. In addition, the activities of p38 Map kinase isoforms that may participate in the insulin's antiapoptotic function in CHO-IR cells were also determined. METHODS: Chinese hamster ovary cells, expressing wild- or mutated human insulin receptors (CHO-IR cells), were used to investigate whether insulin can stimulate any of the isoform(s) of the p38Map kinases. The p38Map kinase activity was determined by measuring the degree of 32P-labelling of ATF-2 protein, a specific substrate of p38Map kinase. A DNA laddering assay was performed to examine the degree of apoptosis and a RT-PCR analysis to determine which isoform(s) of the p38Map kinases were expressed in response to insulin. RESULTS: p38Map kinase activation by insulin was sharply suppressed in only the CHO-IR/A1018K cells, which lack the intrinsic tyrosine kinase activity of insulin receptors. Insulin stimulation of p38Map kinase was insensitive to SB203580, an inhibitor of the alpha(alpha)-and beta(beta)-isoforms of p38Map kinases. Moreover, orthovanadate, known as a specific stimulator of the gamma(gamma)-and delta(delta-) isoforms, stimulated the p38Map kinase activity in CHO-IR cells. Insulin increased the degree of mRNA expression of the delta-isoform, but not that of the alpha-isoform p38Map kinase. Interestingly, PD98059, an inhibitor of ERK, suppressed p38Map kinase stimulation, as well as the antiapoptotic protection of cells by insulin. As insulin was found to still protect ERK-lacking cells (CHO-IR/ SOS) from apoptosis, any substantial role(s) of ERK might be excluded. CONCLUSION: Our data suggest that insulin may stimulate the activity and expression of the-isoform of p38Map kinase in a MEK1/2-dependent manner. The involvement of the delta-isoform of p38Map kinase in insulin's antiapoptotic protection was also suggested, but remains to be investigated further to clarify the nature of its mechanism of action

Insulin-dependent Stimulation of a Subtype of p38Map Kinases and Its Role in Insulin's Antiapoptotic Activity / 대한내분비학회지

BACKGROUND: The p38 mitogen-activated protein kinases (p38Map kinases) are a family of prolinedirected serine/threonine kinases. At least four isoforms of p38Map kinases have been identified; however, their physiological significances remain to be understood. Recently, the role of p38Map kinase in insulin-stimulated glucose uptake has been suggested. The present study aimed to investigate which isoform(s) were responsive to insulin stimulation. In addition, the activities of p38 Map kinase isoforms that may participate in the insulin's antiapoptotic function in CHO-IR cells were also determined. METHODS: Chinese hamster ovary cells, expressing wild- or mutated human insulin receptors (CHO-IR cells), were used to investigate whether insulin can stimulate any of the isoform(s) of the p38Map kinases. The p38Map kinase activity was determined by measuring the degree of 32P-labelling of ATF-2 protein, a specific substrate of p38Map kinase. A DNA laddering assay was performed to examine the degree of apoptosis and a RT-PCR analysis to determine which isoform(s) of the p38Map kinases were expressed in response to insulin. RESULTS: p38Map kinase activation by insulin was sharply suppressed in only the CHO-IR/A1018K cells, which lack the intrinsic tyrosine kinase activity of insulin receptors. Insulin stimulation of p38Map kinase was insensitive to SB203580, an inhibitor of the alpha(alpha)-and beta(beta)-isoforms of p38Map kinases. Moreover, orthovanadate, known as a specific stimulator of the gamma(gamma)-and delta(delta-) isoforms, stimulated the p38Map kinase activity in CHO-IR cells. Insulin increased the degree of mRNA expression of the delta-isoform, but not that of the alpha-isoform p38Map kinase. Interestingly, PD98059, an inhibitor of ERK, suppressed p38Map kinase stimulation, as well as the antiapoptotic protection of cells by insulin. As insulin was found to still protect ERK-lacking cells (CHO-IR/ SOS) from apoptosis, any substantial role(s) of ERK might be excluded. CONCLUSION: Our data suggest that insulin may stimulate the activity and expression of the-isoform of p38Map kinase in a MEK1/2-dependent manner. The involvement of the delta-isoform of p38Map kinase in insulin's antiapoptotic protection was also suggested, but remains to be investigated further to clarify the nature of its mechanism of action

Dysferlin in a hyperCKaemic patient with caveolin 3 mutation and in C2C12 cells after p38 MAP kinase inhibition

Dysferlin is a plasma membrane protein of skeletal muscle whose deficiency causes Miyoshi myopathy, limb girdle muscular dystrophy 2B and distal anterior compartment myopathy. Recent studies have reported that dysferlin is implicated in membrane repair mechanism and coimmunoprecipitates with caveolin 3 in human skeletal muscle. Caveolin 3 is a principal structural protein of caveolae membrane domains in striated muscle cells and cardiac myocytes. Mutations of caveolin 3 gene (CAV3) cause different diseases and where caveolin 3 expression is defective, dysferlin localization is abnormal. We describe the alteration of dysferlin expression and localization in skeletal muscle from a patient with raised serum creatine kinase (hyperCKaemia), whose reduction of caveolin 3 is caused by a CAV3 P28L mutation. Moreover, we performed a study on dysferlin interaction with caveolin 3 in C2C12 cells. We show the association of dysferlin to cellular membrane of C2C12 myotubes and the low affinity link between dysferlin and caveolin 3 by immunoprecipitation techniques. We also reproduced caveolinopathy conditions in C2C12 cells by a selective p38 MAP kinase inhibition with SB203580, which blocks the expression of caveolin 3. In this model, myoblasts do not fuse into myotubes and we found that dysferlin expression is reduced. These results underline the importance of dysferlin-caveolin 3 relationship for skeletal muscle integrity and propose a cellular model to clarify the dysferlin alteration mechanisms in caveolinopathies.

Role of p-38 MAP Kinase in apoptosis of hypoxia-induced osteoblasts / 대한치과교정학회지

Tooth movement by orthodontic force effects great tissue changes within the periodontium, especially by shifting the blood flow in the pressure side and resulting in a hypoxic state of low oxygen tension. The aim of this study is to elucidate the possible mechanism of apoptosis in response to hypoxia in MC3T3E1 osteoblasts, the main cells in bone remodeling during orthodontic tooth movement. MC3T3E1 osteoblasts under hypoxic conditions (2% oxygen) resulted in apoptosis in a time-dependent manner as estimated by DNA fragmentation assay and nuclear morphology stained with fluorescent dye, Hoechst 33258. Pretreatment with Z-VAD-FMK, a pan-caspase inhibitor, or Z-DEVD-CHO, a specific caspase-3 inhibitor, completely suppressed the DNA ladder in response to hypoxia. An increase in caspase-3-like protease (DEVDase) activity was observed during apoptosis, but no caspase-1 activity (YVADase) was detected. To confirm what caspases are involved in apoptosis, Western blot analysis was performed using anti-caspase-3 or -6 antibodies. The 10-kDa protein, corresponding to the active products of caspase-3, and the 10-kDa protein of the active protein of caspase-6 were generated in hypoxia-challenged cells in which the processing of the full length form of caspase-3 and -6 was evident. While a time course similar to this caspase-3 and -6 activation was evident, hypoxic stress caused the cleavage of lamin A, which was typical of caspase-6 activity. In addition, the stress elicited the release of cytochrome c into the cytosol during apoptosis. Furthermore, we observed that pre-treatment with SB203580, a selective p38 mitogen activated protein kinase inhibitor, attenuated the hypoxia-induced apoptosis. The addition of SB203580 suppressed caspase-3 and -6-like protease activity by hypoxia up to 50%. In contrast, PD98059 had no effect on the hypoxia-induced apoptosis. To confirm the involvement of MAP kinase, JNK/SAPK, ERK, or p38 kinase assay was performed. Although p38 MAPK was activated in response to hypoxic treatment, the other MAPK -JNK/SAPK or ERK- was either only modestly activated or not at all. These results suggest that p38 MAPK is involved in hypoxia-induced apoptosis in MC3T3E1 osteoblasts.

A study on the regulatory effect of p-38 MAP kinase on nitric oxide and interleukin-6 in osteoblasts / 대한치과교정학회지

Tooth movement is the result of bone metabolism in the periodontium, where various cytokines take important roles. Interleukin-6(Il-6) and nitrous oxide (NO) were reported to be secreted from osteoblasts in the process of bone resorption. The mechanism of the process has not been clearly understood, but the activation of mitogen-activated protein kinase (MAPK) was known to be an important process in the release of the inflammatory cytokines in macrophages. In this regard, to prove the role of MAPK in the release of IL-6 and NO in MC3T3E-1 osteoblasts, Northern blot analysis, Western blot analysis and immune complex kinase assay were used. As a result, the treatment of MC3T3E-1 osteoblast cultures with combined interferon-gamma (IFN-gamma), lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-alpha) induces expressions of inducible nitric oxide synthase (iNOS) and IL-6, resulting in sustained releases of large amounts of NO and IL-6. However, IFN-gamma, LPS, and TNF-alpha individually induce a non-detectable or small amount of NO and IL-6 in MC3T3E-1 osteoblasts. The role of MAPK activation in the early intracellular signal transduction involved in iNOS and IL-6 transcription in the combined agents-stimulated osteoblasts has been investigated. The p38 MAPK pathway is specifically involved in the combined agents-induced NO and IL-6 release, since NO and IL-6 release in the presence of a specific inhibitor of p38 MAPK, 4-(4-fluorophenyl)-2-(4-metylsulfinylphenyl)-5-(4-pyridyl)imidazole) (SB203580), were significantly diminished. In contrast, PD98059, a specific inhibitor of MEK1, had no effect on NO and IL-6 release. Northern blot analysis showed that the p38 MAPK pathway controlled the iNOS and IL-6 transcription level. These data suggest that p38 MAPK play an important role in the secretion of NO and IL-6 in LPS/IFNgamma- or TNF-alpha/IFN-gamma-treated MC3T3E-1 osteotion of

Characteristics of obesity and role of ERK1/2 and p38MAPK in produetion of adipose tissue in rat with metabolic syndrome / 解放军医学杂志

Objective To observe the characteristics of obesity in rats with metabolic syndrome (MS) and to study the role of ERK1/2 and p38MAPK in the production of adipose tissues. Methods The metabolic parameters, weight of adipose tissue, waist circumference (WC), Lee's index, distribution area of adipocytes and the number of big adipocytes in the rats were measured. Adipose tissues and liver were histopathologically observed. ERK1/2 and p38MAPK of adipose tissue were determined using Western blot. Results (1) The blood pressure, fasting insulin level, LDL-C, TG and FFA in rats with MS were markedly higher than that in control rats (P

GENE EXPRESSION OF p38 MITOGEN-ACTIVATED PROTEIN KINASE AND ITS MAPKKs IN HYPERTROPHIC SCARS / 解放军医学杂志

To explore the change in gene expressions of p38 mitogen-activated protein kinase (p38MAPK) and its upstream signal-regulated molecule (mkk3 and mkk6) in normal skin versus hypertrophic scars underlying its potentially biological significance. Total RNAs were isolated from 8 specimens of hypertrophic scars and 8 specimens of normal skin, then they were purified to mRNAs, and the gene expression of mkk3, mkk6 and p38MAPK was examined with reverse transcription-polymerase chain reaction (RT-PCR). The results showed that the intensities of gene expression of mkk6 and p38MAPK were weak in normal skins, while the expression of these 2 genes was significantly elevated in hypertrophic scars compared with normal skins (P0.05). In hypertrophic scar, the elevation of mkk6 and p38MAPK gene expression, which plays pilot roles in cell proliferation, may be one of the mechanisms controlling the formation of hypertrophic scars.

Effect of MAPK inhibition on the hypoxia hypercapnia-induced pulmonary vasoconstriction / 中国病理生理杂志

AIM:To investigate isometric force displacement in isolated rat main pulmonary artery rings and right main branch pulmonary artery(second pulmonary artery)rings during hypoxia hypercapnia and the role of mitogen activated protein kinase(MAPK).METHODS:The main pulmonary artery rings were dissected from the male Sprague-Dawley rats and were randomly divided into control group and hypoxia hypercapnia group.The second pulmonary artery rings were also randomly divided into control group,hypoxia hypercapnia group,DMSO incubation group,U0126 incubation group and SB203580 incubation group.The tension changes of pulmonary artery rings were monitored in vitro.RESULTS:Under normoxia conditions,there was no statistically significant change between main pulmonary artery rings and second pulmonary artery rings.A biphasic pulmonary artery contractile response to hypoxia hypercapnia in the second pulmonary artery rings was observed instead of a sharp and transient increase in the main pulmonary artery tension.Both p38 MAPK inhibitor SB203580 and ERK1/2 inhibitor U0126 significantly attenuated the delayed,but not early,contractile phase of the biphasic pulmonary artery contraction.CONCLUSION:Acute hypoxia hypercapnia causes a biphasic pulmonary artery contractile response in the second pulmonary artery,and p38 MAPK and ERK1/2 may be two key mediators in the process.

GSH deletion increases the activity of p38MAPK in MNNG treatment / 中国病理生理杂志

AIM: To explore the effect of low concentration of N-methyl-N-nitro-N-nitroguanidine (MNNG) on p38MAPK, and the function of glutathione (GSH) on p38MAPK. METHODS: Western blotting was applied to detect the p38MAPK phosphorylation in MNNG treatment group and control group. To study the effect of GSH on MNNG-regulated p38MAPK activity, the intracellular GSH level was reduced by pretreatment of L-buthionine-S, R-sulfoximine (BSO). Assuming the absorbance of band in control group as 1.0, the relative P/T values of the treatment groups were calculated, with the “P” served as absorbance values of phospho-p38MAPK and the “T” as absorbance values of total p38MAPK. RESULTS: In BSO pretreated groups,the relative P/T in samples treated with MNNG for 2.5 h was 0.84, and became 2.19 with 3 h more incubation in the fresh medium. CONCLUSION: GSH deletion increases the activity of p38MAPK in MNNG treatment.

Role of p38MAPK activation in high glucose-induced collagen Ⅲ synthesis in normal rat kidney tubular epithelial cells NRK52E / 中国病理生理杂志

AIM: To study the role of p38 mitogen-activated protein kinase (p38MAPK) activation in high glucose-induced collagen Ⅲ synthesis in NRK52E cells. METHODS: Normal rat tubular epithelial cell line NRK52E was cultured in D-glucose of different concentrations, pretreated with SB203580 and collected at different time points. The levels of phospho-p38MAPK and extracellular matrix collagen Ⅲ were examined by Western blotting. RESULTS: The activation of p38MAPK was shown to be dependent upon D-glucose concentration and the time-course. Pretreatment with SB203580 blocked p38MAPK activation induced by high concentration of D-glucose in NRK52E cells. CONCLUSIONS: The activation of p38MAPK induced by high concentration of glucose may play a role in diabetic interstital renal fibrosis. SB203580 has a potential value of clinical applications in the prevention and treatment of diabetic nephropathy.

Expression of TGF-?_2,p38MAPK in a model of asthmatic airway remodeling / 中国病理生理杂志

AIM: To detect the expression of IL-13 and TGF-? during airway remodeling. METHODS: A airway remodeling model was established and histological changes were detected under light or electronic microscope. In situ hybridization assays were adopted to determine the status of IL-13 and TGF-?_2 transcript in lung tissue and Western blot was used to detect the expression of p38MAPK protein. RESULTS: Proliferation of airway epithelium and smooth muscle and mucous plugs were found in lung tissue of airway remodeling mice , accompanied by infiltration of eosinophils and lymphocytes in airway. Overexpression of IL-13,TGF-?_2 mRNA and p38MAPK were also observed in airway remodeling group. CONCLUSION: Expression of IL-13, TGF-?_2 mRNA and p38MAPK protein increased significantly during airway remodeling, which may suggest an role for Th2 cytokines, TGF-?_2 in the pathogenesis of airway remodeling. p38 MAPK may be associated with the development of asthma and airway remodeling. [

Association among COX_2, iNOS and p38MAPK in late phase of preconditioning in rat cardiomyocytes / 中国病理生理杂志

0.05). The LDH was lower ,and cell viability was higher in group IPC than those in control group. The LDH was higher ,and cell viability was lower in grou p SMT, group NS 398 and group SB than those in group IPC. CONCLUSIONS: In late p hase of preconditioning ,the p38MAPK activity and expression of iNOS and COX 2 increase significantly in rat cardiomyocytes, activited p38MAPK mediates iNOS ,then promotes COX 2 expression.

The Role of p38 MAP Kinase Signal Transduction in the Induction of MUC 8 Gene Expression in Normal Human Nasal Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: In cystic fibrosis, chronic bronchitis, and asthma, the mucociliary mechanism is impaired when mucin is produced excessively. The mRNA encoding MUC8 has been shown to be the major up-regulated mucin under inflammatory condition and is likely to contribute to the airway mucus plugging characteristic of these diseases. The aim of this study is to determine the intracellular signaling pathway directly involved in the MUC8 regulation following inflammatory mediator treatments. MATERIALS AND METHOD: Passage-2 normal human airway epithelial cells were used in all experiments. Inflammatory signal-induced MAP kinase activity was measured by Western blot analysis using phosphospecific anti-active MAP kinase antibodies. Inflammatory signal-induced MUC8 expression was measured in the absence or presence of SB203580 by the semi-quantative RT-PCR. RESULTS: Inflammatory stimuli such as LPS, TNF-alpha, and IL-lbeta activated the p38 MAP kinase and subsequently up-regulated the MUC8 expression. Interestingly, the TNF-alpha or IL-lbeta-inducibility of the MUC8 gene expression was greatly enhanced by specific inhibition of the p38 MAP kinase by using SB 203580 CONCLUSION: These results suggest that the intracellular p38 MAP kinase activity is a negative regulator for the MUC8 up-regulation in human nasal epithelial cells following infiammatory stimuli.

Effects of 11, 12-EET and ischemic preconditioning on phosphorylated ERK and p38 MAPK during ischemia and reperfusion in rat myocardium / 中国病理生理杂志

AIM: In order to study the relationship between the ERK and p38 MAPK activation and the protection of 11, 12-epoxyeicosatrienoic acid (11, 12-EET) and ischemia preconditioning (IP), the effects of 11, 12-EET and ischemic preconditioning on phosphorylated ERK and p38 MAPK during ischemia and reperfusion in rat myocardium were examined. METHODS: The rat heart was subjected to ischemia for 5 min by ligating the left anterior descending coronary artery followed by reperfusion for 5 min (two times) to undergo ischemia preconditioning. The rats were divided into 5 groups: (1) control; (2) sham group; (3) ischemia/reperfusion (I/R) group, in which the rat heart suffered from 60 min ischemia followed by 30 min reperfusion; (4) IP plus I/R group; (5) EET plus I/R group, in which 6.28?10 -8 mol/L 11, 12-EET was injected intravenously 20 min before I/R. The heart function was examined, and phosphorylated ERK and p38 MAPK were detected by Western blot. RESULTS: At 30 min reperfusion, +dp/dt max ,-dp/dt max and LVDP decreased significantly in I/R group compared with sham group, IP plus I/R group and EET plus I/R group; Phosphorylated ERK1/2 level was higher in I/R group than sham group, but was lower in I/R group than IP plus I/R group and EET plus I/R group; Phosphorylated p38 MAPK level was lower in control, sham, IP plus I/R and EET plus I/R group than I/R group. CONCLUSION: 11,12-EET protects rat heart against ischemia/reperfusion injury, the mechanism may be related to activation of ERK1/2 and inhibition of p38 MAPK. [