curcumin and pyrazolanthrone

Acute lung injury (ALI) is characterized by high prevalence and high mortality. Thus far, no effective pharmacological treatment has been made for ALI in clinics. Inflammation is critical to the development of ALI. Curcumin analog C66, having reported as an inhibitor of c-Jun N-terminal kinase (JNK), exhibits anti-inflammatory property both in vitro and in vivo. However, whether C66 is capable of reducing lipopolysaccharide (LPS)-induced ALI through the inhibition of inflammation by targeting JNK remains unknown.. Intratracheal injection of LPS was employed to build a mouse ALI model. H&E staining, wet/dry ratio, immunofluorescence staining, inflammatory cell detection, and inflammatory gene expression were used to evaluate lung injury and lung inflammation. In vitro, LPS was used to induce the expression of inflammatory cytokines both in protein and gene levels.. The results of our studies showed that the pretreatment with C66 and JNK inhibitor SP600125 was capable of attenuating the LPS-induced ALI by detecting pulmonary edema, pathological changes, total protein concentration, and inflammatory cell number in bronchoalveolar lavage fluid (BALF). Besides, C66 and SP600125 also suppressed LPS-induced inflammatory cytokine expression in BALF, serum, and lung tissue. In vitro, LPS-induced production of TNF-α and IL-6 and gene expression of TNF-α, IL-6, IL-1β, and COX-2 could be inhibited by the pretreatment with C66 and SP600125. It was found that C66 and SP600125 could inhibit LPS-induced phosphorylation of JNK both in vitro and in vivo.. In brief, our results suggested that C66 protects LPS-induced ALI through the inhibition of inflammation by targeting the JNK pathway. These findings further confirmed the pivotal role of JNK in ALI and implied that C66 is likely to serve as a potential therapeutic agent for ALI.

Topics: Acute Lung Injury; Animals; Anthracenes; Cells, Cultured; Curcumin; Disease Models, Animal; Dose-Response Relationship, Drug; Inflammation; Injections, Intravenous; JNK Mitogen-Activated Protein Kinases; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Molecular Structure; Phosphorylation; Structure-Activity Relationship

Topics: Abietanes; Anthracenes; Antineoplastic Agents; Curcumin; Gene Expression Regulation, Leukemic; Humans; K562 Cells; Leukemia; Promoter Regions, Genetic; Protein Kinase Inhibitors; Transcription Factor AP-1; WT1 Proteins

To examine whether curcumin has protective effect on insulin resistance induced by bisphenol A (BPA) in LO2 cells and whether this effect was mediated by inhibiting the inflammatory mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) pathways.. LO2 cells were stimulated with BPA in the presence or absence of curcumin for 5 days. Glucose consumption, activation of insulin signaling, MAPKs and NF-κB pathways, levels of inflammatory cytokines and MDA production were analyzed.. Curcumin prevented BPA-induced reduction of glucose consumption and suppression of insulin signaling pathway, indicating curcumin alleviated BPA-triggered insulin resistance in LO2 cells. mRNA and proteins levels of TNF-α and IL-6, as well as MDA level in LO2 cells treated with BPA were decreased by curcumin. Furthermore, curcumin downregulated the activation of p38, JNK, and NF-κB pathways upon stimulation with BPA. Inhibition of JNK pathway, but not p38 nor NF-κB pathway, improved glucose consumption and insulin signaling in BPA-treated LO2 cells.. Curcumin inhibits BPA-induced insulin resistance by suppressing JNK pathway.

Topics: Anthracenes; Benzhydryl Compounds; Cell Line; Curcumin; Enzyme Activation; Humans; Imidazoles; Inflammation; Insulin Resistance; MAP Kinase Signaling System; NF-kappa B; Oxidative Stress; Phenols; Pyridines; Pyrrolidines; Thiocarbamates

Brain expressed X-linked (Bex) genes are newer group of pro-apoptotic genes. Role of any Bex gene in neuroblastoma and Bex4 and Bex6 in any cancer is completely unknown. Re-expression of all endogenous Bex genes by any nutraceutical is also unknown. Therefore, we investigated the induction of all endogenous Bex genes and associated mechanisms by curcumin using N2a, an aggressive neuroblastoma cell line. Curcumin induced all endogenous Bex genes prior to apoptosis in N2a cells in a dose- and time-dependent manner. Wortmannin (PI-3Kinases inhibitor), SP600125 (JNK inhibitor) and pifithrin-α (p53 inhibitor) abrogated curcumin-mediated induction of Bex genes. Inhibition of curcumin-mediated induction of Bex genes by pifithrin-α also inhibited N2a cells apoptosis suggesting, a direct role of Bex genes in N2a cells apoptosis and involvement of p53 in Bex genes induction. Curcumin treatment activated p53 through hyperphosphorylation at serine 15 before Bex genes induction indicating Bex genes are novel downstream targets of p53. Collectively, curcumin, a safe nutraceutical has the potential to induce all endogenous Bex genes to harness their anti-cancer properties in neuroblastoma cells. Re-expression of Bex genes by curcumin acts as tumor suppressors and may provide alternate strategy to treat neuroblastomas and other cancers with silenced Bex genes.

Topics: Androstadienes; Animals; Anthracenes; Apoptosis; Benzothiazoles; Cell Line, Tumor; Curcumin; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Gene Expression Regulation, Neoplastic; JNK Mitogen-Activated Protein Kinases; Mice; Models, Biological; Nerve Tissue Proteins; Neuroblastoma; Phosphatidylinositol 3-Kinases; Phosphorylation; Promoter Regions, Genetic; Signal Transduction; Time Factors; Toluene; Tumor Suppressor Protein p53; Wortmannin

Cardiovascular diseases as leading causes of the mortality world-wide are related to diabetes. The present study was to explore the protective effect of curcumin analogue C66 on diabetes-induced pathogenic changes of aortas. Diabetes was induced in male C57BL/6 mice with a single intraperitoneal injection of streptozotocin. Diabetic mice and age-matched non-diabetic mice were randomly treated with either vehicle (Control and Diabetes), C66 (C66 and Diabetes/C66) or c-Jun N-terminal kinase (JNK) inhibitor (sp600125, JNKi and Diabetes/JNKi). All three treatments were given by gavage at 5 mg/kg every other day for 3 months. Aortic inflammation, oxidative stress, fibrosis, cell apoptosis and proliferation, Nrf2 expression and transcription were assessed by immunohistochemical staining for the protein level and real-time PCR method for mRNA level. Diabetes increased aortic wall thickness and structural derangement as well as JNK phosphorylation, all of which were attenuated by C66 treatment as JNKi did. Inhibition of JNK phosphorylation by C66 and JNKi also significantly prevented diabetes-induced increases in inflammation, oxidative and nitrative stress, apoptosis, cell proliferation and fibrosis. Furthermore, inhibition of JNK phosphorylation by C66 and JNKi significantly increased aortic Nrf2 expression and transcription function (e.g. increased expression of Nrf2-downstream genes) in normal and diabetic conditions. These results suggest that diabetes-induced pathological changes in the aorta can be protected by C66 via inhibition of JNK function, accompanied by the up-regulation of Nrf2 expression and function.

Topics: Animals; Anthracenes; Anti-Inflammatory Agents, Non-Steroidal; Aorta; Apoptosis; Blotting, Western; Cell Proliferation; Cells, Cultured; Curcumin; Diabetes Mellitus, Experimental; Diabetic Cardiomyopathies; JNK Mitogen-Activated Protein Kinases; Male; Mast Cells; Mice; Mice, Inbred C57BL; NF-E2-Related Factor 2; Phosphorylation; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Transforming growth factor β (TGFβ) is a key regulator associated with the pathogenesis of gingival overgrowth (GO). Connective tissue growth factor (CTGF/CCN2) is overexpressed in GO tissues. CCN2 promotes and sustains fibrosis initiated by TGFβ. Previous studies have shown that JNK and Smad3 activation is required for TGFβ-induced CCN2 expressions in human gingival fibroblasts (HGFs). In this study, we have found that Src is a major signaling mediator for TGFβ-induced CCN2 expressions in HGFs. Pre-treatment with 2 Src kinase inhibitors (PP2, Src inhibitor-1) significantly reduced TGFβ1-induced CCN2 synthesis and JNK and Smad3 activation in HGFs. These results suggest that Src is an upstream signaling transducer of JNK and Smad3 with respect to TGFβ1-stimulated CCN2 expression in HGFs. We further found that curcumin significantly abrogated the TGFβ1-induced CCN2 in HGFs by inhibiting the phosphorylations of Src, JNK, and Smad3. Furthermore, curcumin inhibited TGFβ1-induced HGF migration and α-SMA expression. Curcumin potentially qualifies as a useful agent for the control of GO.

Topics: Anthracenes; Anti-Inflammatory Agents, Non-Steroidal; Catechin; Cell Culture Techniques; Cell Movement; Cells, Cultured; Connective Tissue Growth Factor; Curcumin; Enzyme Inhibitors; Fibroblasts; Flavonoids; Gingiva; Gingival Overgrowth; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Imidazoles; Lovastatin; MAP Kinase Kinase 4; Phosphorylation; Protein Kinase Inhibitors; Pyridines; Pyrimidines; Signal Transduction; Smad3 Protein; src-Family Kinases; Transforming Growth Factor beta1

Infection with Helicobacter pylori is important in the development and progression of gastric cancer. However, the mechanisms that regulate this activation in gastric tumors remain elusive. CACUL1 has been cloned and identified as a novel gene that is expressed in many types of cancer and is involved in cell cycle regulation and tumor growth. The current study aimed to examine the expression of CACUL1 in gastric cancer samples and analyze its correlation with H. pylori infection. We found that CACUL1 was highly expressed in gastric cancer tissues and negatively correlated with gastric cancer differentiation and TNM stage. In addition, CACUL1 expression was high in H. pylori-infected tissues compared with H. pylori non-infected tissue. We found that H. pylori could up-regulate CACUL1 expression through activating protein 1. The up-regulation of CACUL1 expression could promote matrix metalloproteinase 9 and Slug expression to increase invasion and metastasis of tumor cells. These results suggested that H. pylori-triggered CACUL1 production occurred in an activating protein 1-dependent manner and regulated matrix metalloproteinase 9 and Slug expression to affect the invasion and metastasis of tumor cells. Therefore, CACUL1 is a potential therapeutic target for the treatment of aggressive gastric cancer.

Topics: Adult; Aged; Aged, 80 and over; Animals; Anthracenes; Cell Line, Tumor; Cullin Proteins; Curcumin; Female; Gastric Mucosa; Gene Expression Regulation, Neoplastic; Helicobacter pylori; Humans; Male; Matrix Metalloproteinase 9; Mice; Middle Aged; Neoplasm Invasiveness; Neoplasm Metastasis; Phosphorylation; Promoter Regions, Genetic; Proto-Oncogene Proteins c-fos; Stomach; Stomach Neoplasms; Transcription Factor AP-1; Transcriptional Activation; Up-Regulation; Young Adult

Macrophage infiltration contributes to the pathogenesis of diabetic renal injury. However, the regulatory mechanisms between macrophage infiltration and epithelial cell activation are still unclear. Our previous study found that C66, a novel curcumin analog, was able to inhibit inflammatory cytokine expression in vitro and in vivo. This study further elucidated whether C66 can prevent glucose-induced renal epithelial activation and inflammatory macrophage infiltration by a MAPK/NF-κB medicated mechanism. Our data show that pretreatment with C66 not only significantly reduced high glucose (HG)-induced over-expressions of VCAM-1, ICAM-1 and MCP-1, but also remarkably inhibited NF-κB activation, MAPKs phosphorylation, and subsequently macrophage adhesion in renal epithelial NRK-52E cells. Furthermore, we find that MAPKs, especially JNK, play important roles in HG-induced NF-κB activation, which regulates the over-expression of adhesion molecules in HG-stimulated NRK-52E cells. A molecular docking predicted that C66 may target JNK2, which leads to its anti-inflammatory actions. In vivo, administration of C66 or JNK special inhibitor SP600125 at 5 mg/kg markedly decreased diabetes-induced renal adhesion molecule expression, NF-κB activation, inflammatory cell infiltration, and pathological indexes in the kidneys of diabetic mice. These findings provide a perspective on the renoprotective effects of C66 in diabetes, and outline a novel therapeutic strategy of JNK inhibition for the treatment of diabetic nephropathy.

Topics: Animals; Anthracenes; Cell Line; Chemokine CCL2; Curcumin; Diabetes Mellitus, Experimental; Diabetic Nephropathies; Enzyme Inhibitors; Gene Expression Regulation; Intercellular Adhesion Molecule-1; Male; MAP Kinase Kinase 4; MAP Kinase Signaling System; Mice; NF-kappa B; Phosphorylation; Vascular Cell Adhesion Molecule-1

Combined curcumin and PS-341 treatment has been reported to enhance cytotoxicity and minimize adverse effects through ERK and p38MAPK mechanisms in human multiple myeloma cells. However, whether JNK plays similar role in this process remains unclear. In the present study, we found combined treatment altered NF-κB p65 expressions and distributions in multiple myeloma H929 cells. Western blot analysis showed combined treatment inactivated NF-κB while activated JNK signaling. Pre-treatment with JNK inhibitor SP600125 could attenuate NF-κB inactivation and restored H929 cells' survival. These results suggested that curcumin might enhance the cytotoxicity of PS-341 by interacting with NF-κB, at least in part, through JNK mechanism.

Topics: Anthracenes; Antineoplastic Agents; Apoptosis; Boronic Acids; Bortezomib; Cell Line, Tumor; Curcumin; Drug Synergism; Extracellular Signal-Regulated MAP Kinases; Humans; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Multiple Myeloma; p38 Mitogen-Activated Protein Kinases; Pyrazines; Transcription Factor RelA

Tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine with a critical role in osteoarthritis (OA), was primarily produced by monocytes/macrophages and plays a crucial role in the inflammatory response. Here, we investigated the intracellular signaling pathways involved in TNF-α-induced monocyte chemoattractant protein 1 (MCP-1)/CCL2 expression in human synovial fibroblast cells. Stimulation of synovial fibroblasts (OASF) with TNF-α induced concentration- and time-dependent increases in CCL2 expression. TNF-α-mediated CCL2 production was attenuated by TNFR1 monoclonal antibody (Ab). Pretreatment with an apoptosis signal-regulating kinase 1 (ASK1) inhibitor (thioredoxin), JNK inhibitor (SP600125), p38 inhibitor (SB203580), or AP-1 inhibitor (curcumin or tanshinone IIA) also blocked the potentiating action of TNF-α. Stimulation of cells with TNF-α enhanced ASK1, JNK, and p38 activation. Treatment of OASF with TNF-α also increased the accumulation of phosphorylated c-Jun in the nucleus, AP-1-luciferase activity, and c-Jun binding to the AP-1 element on the CCL2 promoter. TNF-α-mediated AP-1-luciferase activity and c-Jun binding to the AP-1 element were inhibited by TNFR1 Ab, thioredoxin, SP600125, and SB203580. Our results suggest that the interaction between TNF-α and TNFR1 increases CCL2 expression in human synovial fibroblasts via the ASK1, JNK/p38, c-Jun, and AP-1 signaling pathway.

Topics: Anthracenes; Antibodies; Bursa, Synovial; Chemokine CCL2; Curcumin; Dose-Response Relationship, Drug; Fibroblasts; Gene Expression Regulation; Genes, Reporter; Humans; Imidazoles; Luciferases; MAP Kinase Kinase 4; MAP Kinase Kinase Kinase 5; Osteoarthritis; p38 Mitogen-Activated Protein Kinases; Primary Cell Culture; Pyridines; Receptors, Tumor Necrosis Factor, Type I; Signal Transduction; Thioredoxins; Transcription Factor AP-1; Tumor Necrosis Factor-alpha

We investigated the unknown molecular mechanisms of Interleukin-1 (IL-1β)-induced cartilage aggrecan degeneration by aggrecanase (ADAMTS-A Disintegrin And Metalloproteinase with ThromboSpondin motifs) in human articular chondrocytes, a model mimicking human arthritis.. Chondrocytes were pretreated with various pharmacological inhibitors and then stimulated with IL-1β for 24 h. ADAMTS-4 expression or activity was studied by RT-PCR or ELISA and other proteins measured by Western blotting.. MAP kinase kinase-specific inhibitor, U0126 inhibited IL-1-induced phosphorylation of ERK1/2 and down-regulated ADAMTS-4 expression and activity. Protein 38 inhibitor, SB203580 down-regulated the phosphorylation of p38 and its target, activating transcription factor-2 (ATF-2), ADAMTS-4 mRNA and activity. C-Jun N-terminal kinase (JNK) inhibitor, SP600125 diminished IL-1-stimulated JNK phosphorylation, ADAMTS-4 mRNA expression and enzyme activity. A c-fos/lipoxygenase pathway inhibitor and antioxidant, nordihydroguaiaretic acid (NDGA) significantly suppressed ADAMTS-4 mRNA induction and activity. Activating protein (AP-1) and nuclear factor kappa B (NF-ĸB) transcription factor inhibitors, curcumin and pyrrolidine dithiocarbamate (PDTC) partially inhibited ADAMTS-4 induction and activity.. These results suggest partial involvement of ERK-, p38-and JNK-MAPKs as well as AP-1, ATF-2 and NF-ĸB transcription factors in IL-1-induced ADAMTS-4 in chondrocytes. Inhibition of these targets by the specific pharmacological agents could be useful for reducing aggrecanase-driven cartilage resorption in arthritis.

Topics: Anthracenes; Butadienes; Cartilage, Articular; Cells, Cultured; Chondrocytes; Curcumin; Endopeptidases; Gene Expression Regulation; Humans; Imidazoles; Interleukin-1beta; JNK Mitogen-Activated Protein Kinases; Lipoxygenases; Masoprocol; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; NF-kappa B; Nitriles; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Pyridines; Pyrrolidines; RNA, Messenger; Thiocarbamates; Transcription Factor AP-1

Lead, a ubiquitous heavy metal, is an important industrial and environmental pollutant that can target the vascular endothelium. To clarify the effects of lead on the unfolded protein response (UPR) and their significance in cytotoxicity, we examined the expression and function of endoplasmic reticulum (ER) chaperones glucose-regulated protein 78 (GRP78) and glucose-regulated protein 94 (GRP94) in vascular endothelial cells. We used bovine aortic endothelial cells as an in vitro model of the vascular endothelium. Exposure of vascular endothelial cells to lead nitrate resulted in a marked induction of GRP78 and GRP94 messenger RNA levels. In response to lead, the expression of GRP78 and GRP94 proteins also significantly increased in a dose- and time-dependent manner. In addition, small interfering RNA (siRNA)-mediated knockdown of GRP78 significantly enhanced lead-induced cytotoxicity. Compared with other metal(loid)s, including cadmium chloride, zinc sulfate, copper sulfate, and sodium arsenite, lead nitrate was found to be the most potent metal to induce these chaperones in endothelial cells. In the examined UPR pathways, lead increased the phosphorylation of inositol-requiring enzyme 1 (IRE1) and c-jun N-terminal kinase (JNK). Interestingly, the lead-induced upregulation of GRP78 and GRP94 was almost completely blocked by the JNK inhibitor SP600125 or activator protein-1 (AP-1) inhibitor curcumin. Taken together, these results suggest that lead induces ER stress, but the induction of GRP78 and GRP94 expression via the JNK-AP-1 pathway functions as a defense mechanism against lead-induced cytotoxicity in vascular endothelial cells.

Topics: Animals; Anthracenes; Aorta; Cattle; Curcumin; Endoplasmic Reticulum; Endoplasmic Reticulum Chaperone BiP; Endothelium, Vascular; Environmental Pollutants; Gene Silencing; Heat-Shock Proteins; HSP70 Heat-Shock Proteins; JNK Mitogen-Activated Protein Kinases; Lead; Membrane Proteins; Nitrates; Phosphorylation; Transcription Factor AP-1

Human esophageal epithelial cells play a key role in esophageal inflammation in response to acidic pH during gastroesophageal reflux disease (GERD), increasing secretion of IL-6 and IL-8. The mechanisms underlying IL-6 and IL-8 expression and secretion in esophageal epithelial cells after acid stimulation are not well characterized. We investigated the role of PKC, MAPK, and NF-kappaB signaling pathways and transcriptional regulation of IL-6 and IL-8 expression in HET-1A cells exposed to acid. Exposure of HET-1A cells to pH 4.5 induced NF-kappaB activity and enhanced IL-6 and IL-8 secretion and mRNA and protein expression. Acid stimulation of HET-1A cells also resulted in activation of MAPKs and PKC (alpha and epsilon). Curcumin, as well as inhibitors of NF-kappaB (SN-50), PKC (chelerythrine), and p44/42 MAPK (PD-098059) abolished the acid-induced expression of IL-6 and IL-8. The JNK inhibitor SP-600125 blocked expression/secretion of IL-6 but only partially attenuated IL-8 expression. The p38 MAPK inhibitor SB-203580 did not inhibit IL-6 expression but exerted a stronger inhibitory effect on IL-8 expression. Together, these data demonstrate that 1) acid is a potent inducer of IL-6 and IL-8 production in HET-1A cells; 2) MAPK and PKC signaling play a key regulatory role in acid-mediated IL-6 and IL-8 expression via NF-kappaB activation; and 3) the anti-inflammatory plant compound curcumin inhibits esophageal activation in response to acid. Thus IL-6 and IL-8 expression by acid may contribute to the pathobiology of mucosal injury in GERD, and inhibition of the NF-kappaB/proinflammatory cytokine pathways may emerge as important therapeutic targets for treatment of esophageal inflammation.

Topics: Anthracenes; Anti-Inflammatory Agents; Benzophenanthridines; Cell Line; Curcumin; Enzyme Activation; Epithelial Cells; Esophagus; Flavonoids; Humans; Hydrogen-Ion Concentration; Imidazoles; Interleukin-6; Interleukin-8; Mitogen-Activated Protein Kinases; Mucous Membrane; NF-kappa B; Peptides; Protein Kinase C; Protein Kinase Inhibitors; Pyridines; Signal Transduction; Telomerase; Time Factors; Transcription, Genetic; Up-Regulation

Connective tissue growth factor (CTGF) is associated with the onset and progression of fibrosis in many human tissues. Areca nut (AN) chewing is the most important etiological factor in the pathogenesis of oral submucous fibrosis (OSF). We immunohistochemically examined the expression of CTGF protein in 20 cases of OSF and found positive CTGF staining in fibroblasts and endothelial cells in all cases. Western blot analysis showed that arecoline, a main alkaloid found in AN, stimulated CTGF synthesis in a dose- and time-dependent manner in buccal mucosal fibroblasts. Constitutive overexpression of CTGF during AN chewing may enhance the fibrotic activity in OSF and play a role in the pathogenesis of OSF. Pretreatment with NF-kappaB inhibitor Bay 11-7082, JNK inhibitor SP600125, p38 MAPK inhibitor SB203580 and antioxidant N-acetyl-l-cysteine, but not ERK inhibitor PD98059, significantly reduced arecoline-induced CTGF synthesis. Furthermore, curcumin completely inhibited arecoline-induced CTGF synthesis and the inhibition is dose-dependent. These results indicated that arecoline-induced CTGF synthesis was mediated by ROS, NF-kappaB, JNK, P38 MAPK pathways and curcumin could be a useful agent in controlling OSF.

Topics: Anthracenes; Anti-Inflammatory Agents, Non-Steroidal; Arecoline; Cheek; Cholinergic Agonists; Connective Tissue Growth Factor; Curcumin; Endothelial Cells; Epithelial Cells; Fibroblasts; Flavonoids; Humans; Imidazoles; Mouth Mucosa; Nitriles; Oral Submucous Fibrosis; Pyridines; Sulfones

To investigate the attenuating effect of curcumin, an anti-inflammatory compound derived from dietary spice turmeric (Curcuma longa) on the pro-inflammatory insulin-resistant state in 3T3-L1 adipocytes.. Glucose uptake rate was determined with the [3H] 2-deoxyglucose uptake method. Expressions of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were measured by quantitative RT-PCR analysis and ELISA. Nuclear transcription factor kappaB p65 (NF-kappa p65) and mitogen-activated protein kinase (MAPKs) were detected by Western blot assay.. The basal glucose uptake was not altered, and curcumin increased the insulin-stimulated glucose uptake in 3T3-L1 cells. Curcumin suppressed the transcription and secretion of TNF-alpha and IL-6 induced by palmitate in a concentration-dependent manner. Palmitate induced nuclear translocation of NF-kappaB. The activities of Jun NH2-terminal kinase (JNK), extracellular signal-regulated kinase1/2 (ERK1/2) and p38MAPK decreased in the presence of curcumin. Moreover, pretreatment with SP600125 (inhibitor of JNK) instead of PD98059 or SB203580 (inhibitor of ERK1/2 or p38MAPK, respectively) decreased the up-regulation of TNF-alpha induced by palmitate.. Curcumin reverses palmitate-induced insulin resistance state in 3T3-L1 adipocytes through the NF-kappaB and JNK pathway.

Topics: 3T3-L1 Cells; Animals; Anthracenes; Anti-Inflammatory Agents, Non-Steroidal; Curcumin; Glucose; Insulin; Insulin Resistance; Interleukin-6; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mice; NF-kappa B; Palmitates; Protein Kinase Inhibitors; Tumor Necrosis Factor-alpha; Up-Regulation

Glutamate induces cell death by upsetting the cellular redox homeostasis, termed oxidative glutamate toxicity, in a mouse hippocampal cell line, HT22. Extracellular signal-regulated kinases (ERK) 1/2 are known key players in this process. Here we characterized the roles of both MAP kinases and cell cycle regulators in mediating oxidative glutamate toxicity and the neuroprotective mechanisms of curcumin in HT22 cells. c-Jun N-terminal kinase (JNK) and p38 kinase were activated during the glutamate-induced HT22 cell death, but at a later stage than ERK activation. Treatment with a JNK inhibitor, SP600125, or a p38 kinase inhibitor, SB203580, partly attenuated this cell death. Curcumin, a natural inhibitor of JNK signaling, protected the HT22 cells from glutamate-induced death at nanomolar concentrations more efficiently than SP600125. These doses of curcumin affected neither the level of intracellular glutathione nor the level of reactive oxygen species, but inactivated JNK and p38 significantly. Moreover, curcumin markedly upregulated a cell-cycle inhibitory protein, p21cip1, and downregulated cyclin D1 levels, which might help the cell death prevention. Our results suggest that curcumin has a neuroprotective effect against oxidative glutamate toxicity by inhibiting MAP kinase signaling and influencing cell-cycle regulation.

Topics: Animals; Anthracenes; Antioxidants; Cell Death; Cell Line; Curcumin; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p21; Glutamic Acid; Glutathione; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mice; Neuroprotective Agents; Oxidative Stress; Phosphorylation; Reactive Oxygen Species; Transcription Factor AP-1

The aim of this study was to evaluate the usefulness of human intestinal LS180 cells for studying the induction of CYP3A4 mRNA expression via vitamin D receptor (VDR). CYP3A4 mRNA expression in LS180 cells treated with 100 nM 1alpha,25-dihydroxyvitamin D(3) (1alpha,25(OH)(2)D(3)) for 6 and 24 h was approximately 80- and 500-fold higher than the control, respectively. A protein kinase (PK) inhibitor (staurosporine), c-jun N-terminal kinase (JNK) pathway inhibitor (curcumin), and JNK inhibitor (SP600125) attenuated 1alpha,25(OH)(2)D(3)-induced CYP3A4 mRNA expression, suggesting that the PK-JNK pathway contributed to the rapid and drastic induction of CYP3A4 expression via VDR in LS180 cells. The ability of CYP3A4 mRNA induction in LS180 cells was highly dependent on the site and number of vitamin D(3) and D(2) hydroxylation. In addition, short-time (6 h) treatment of LS180 cells with cytotoxic secondary bile acids, lithocholic acid (LCA) and 3-keto-LCA also significantly induced the mRNA expression of CYP3A4. LS180 cells may be useful to quickly investigate the CYP3A4-inducing effect of drugs, xenobiotics, and/or endogenous substrates in the intestinal epithelia.

Topics: Anthracenes; Calcitriol; Cell Line; Curcumin; Cytochrome P-450 CYP3A; Cytochrome P-450 Enzyme System; Enzyme Induction; Humans; Hydroxylation; Intestinal Mucosa; JNK Mitogen-Activated Protein Kinases; Lithocholic Acid; Molecular Structure; Protein Kinase Inhibitors; Receptors, Calcitriol; RNA, Messenger; Staurosporine; Time Factors; Vitamin D

Curcumin, the major pigment of the dietary spice turmeric has the potential for chemoprevention by promotion of apoptosis. Mitogen-activated protein kinase (MAPK) and NF-kappa B (NFkappaB) signalling cascades are thought to regulate apoptosis and cell survival. While curcumin inhibits NFkappaB, its effects upon the MAPK pathways are unclear. This study investigates curcumin effects upon MAPK signalling and apoptosis in HCT116 cells. Here we report that curcumin time- and dose-dependent induction of apoptosis were accompanied by sustained phosphorylation and activation of c-jun N-terminal kinase (JNK) and p38 MAPK as well as inhibition of constitutive NFkappaB transcriptional activity. Curcumin treatment also induced JNK-dependent sustained phosphorylation of c-jun and stimulation of AP-1 transcriptional activity. Curcumin-mediated c-jun phosphorylation and apoptosis were reduced by treatment with the JNK-specific inhibitor SP600125. Conversely, the p38-specific inhibitor SB203580 had no effect upon curcumin-induced apoptosis. Curcumin treatment had no effect on the activity of extracellular signal-regulated protein kinase (ERK). Taken together, our data show for the first time that JNK, but not p38 or ERK signalling, plays an important role in curcumin-mediated apoptosis in human colon cancer cells that may underlie its chemopreventive effects.

Topics: Anthracenes; Apoptosis; Cell Line, Tumor; Colonic Neoplasms; Curcumin; Enzyme Inhibitors; Humans; Imidazoles; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mitogen-Activated Protein Kinases; NF-kappa B; Pyridines; Signal Transduction

Aplidine is a promising antitumor agent derived from the Mediterranean tunicate Aplidium albicans. We have found that Aplidine at nM concentrations (10-100 nM) induced apoptosis in human leukemic cell lines and primary leukemic cell cultures from leukemic patients. Inhibition of the Fas (CD95)/Fas ligand (CD95L) signaling pathway with an antagonistic anti-Fas antibody partially inhibited Aplidine-induced apoptosis. L929 cells were resistant to Aplidine action but underwent apoptosis after transfection with human Fas cDNA. Aplidine induced a rapid and sustained c-Jun NH(2)-terminal kinase activation, and pretreatment with curcumin or SP600125 inhibited Aplidine-induced c-Jun NH(2)-terminal kinase activation and apoptosis. However, inhibition of extracellular signal-regulated kinase and p38 kinase signaling pathways did not affect Aplidine-induced apoptosis. Aplidine induced caspase-3 activation, and caspase inhibition prevented Aplidine-induced apoptosis. Aplidine failed to induce apoptosis in MCF-7 breast cancer cells, defective in caspase-3, additionally implicating caspase-3 in its proapoptotic action. Aplidine also triggered an early release of cytochrome c from mitochondria, and overexpression of bcl-2 by gene transfer abrogated mitochondrial cytochrome c release and apoptosis. Aplidine rapidly induced cleavage of Bid, a mediator that connects the Fas/CD95 cell death receptor to the mitochondrial apoptosis pathway. Primary cultures of normal human cells, including hepatocytes and resting peripheral blood lymphocytes, were spared or weakly affected after Aplidine treatment. Nevertheless, mitogen (phytohemagglutinin/interleukin-2)-activated T lymphocytes resulted sensitively to the apoptotic action of Aplidine. Thus, Aplidine is an extremely potent and rapid apoptotic inducer on leukemic cells that triggers Fas/CD95- and mitochondrial-mediated apoptotic signaling routes, and shows a rather selective apoptotic action on cancer cells and activated T cells.

Topics: Anthracenes; Apoptosis; BH3 Interacting Domain Death Agonist Protein; Blotting, Western; Carrier Proteins; Caspase 3; Caspases; Cell Line, Tumor; Cells, Cultured; Curcumin; Cytochromes c; Depsipeptides; DNA, Complementary; Dose-Response Relationship, Drug; Enzyme Activation; fas Receptor; Flow Cytometry; Glutathione Transferase; Hepatocytes; HL-60 Cells; Humans; JNK Mitogen-Activated Protein Kinases; Jurkat Cells; Leukemia; MAP Kinase Kinase 4; Microscopy, Fluorescence; Mitochondria; Mitogen-Activated Protein Kinase Kinases; Mitogen-Activated Protein Kinases; Peptides, Cyclic; Protein Transport; Proto-Oncogene Proteins c-bcl-2; Signal Transduction; Time Factors; Tumor Cells, Cultured