Lysophosphatidylcholine activates mesangial cell PKC and MAP kinase by PLCγ-1 and tyrosine kinase-Ras pathways

Bassa, Babu V.; Roh, Daeyoung; Vaziri, Nosratola D.; Kirschenbaum, Michael A.; Kamanna, Vaijinath S.

doi:10.1152/ajprenal.1999.277.3.f328

Cited by 44 publications

(41 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From phosphatidylcholine, lysophosphatidylcholine is generated intracellularly by phospholipase A2. Lysophosphatidylcholine activates ERK through the phosphatidylinositol 3-kinase/Janus kinase 2/MEK-1-dependent pathway in endothelial cells (49) and through the tyrosine kinase-Ras-dependent pathway in mesangial cells (50). Thus, a parsimonious working hypothesis is that VPA in neuronal cells affects lysophosphatidylcholine accumulation or valproyl-lysophosphatidylcholine is a potent or long lasting inducer of ERK pathway.…”

Section: Discussionmentioning

confidence: 99%

The Mood Stabilizer Valproic Acid Activates Mitogen-activated Protein Kinases and Promotes Neurite Growth

Yuan¹,

Huang²,

Jiang³

et al. 2001

Journal of Biological Chemistry

300

239

View full text Add to dashboard Cite

The mood-stabilizing agents lithium and valproic acid (VPA) increase DNA binding activity and transactivation activity of AP-1 transcription factors, as well as the expression of genes regulated by AP-1, in cultured cells and brain regions involved in mood regulation. In the present study, we found that VPA activated extracellular signal-regulated kinase (ERK), a kinase known to regulate AP-1 function and utilized by neurotrophins to mediate their diverse effects, including neuronal differentiation, neuronal survival, long term neuroplasticity, and potentially learning and memory. VPA-induced activation of ERK was blocked by the mitogen-activated protein kinase/ERK kinase inhibitor PD098059 and dominant-negative Ras and Raf mutants but not by dominant-negative stress-activated protein kinase/ERK kinase and mitogen-activated protein kinase kinase 6 mutants. VPA also increased the expression of genes regulated by the ERK pathway, including growth coneassociated protein 43 and Bcl-2, promoted neurite growth and cell survival, and enhanced norepinephrine uptake and release. These data demonstrate that VPA is an ERK pathway activator and produces neurotrophic effects.

show abstract

Section: Discussionmentioning

confidence: 99%

The Mood Stabilizer Valproic Acid Activates Mitogen-activated Protein Kinases and Promotes Neurite Growth

Yuan¹,

Huang²,

Jiang³

et al. 2001

Journal of Biological Chemistry

300

239

View full text Add to dashboard Cite

show abstract

“…Activated simvastatin was prepared as described previously (66) and adjusted to a final concentration of 10 mM with sterile PBS (pH 7.2).…”

Section: Methodsmentioning

confidence: 99%

Cholesterol targeting alters lipid raft composition and cell survival in prostate cancer cells and xenografts

Zhuang

Kim²,

Adam³

et al. 2005

J. Clin. Invest.

298

307

View full text Add to dashboard Cite

Lipid rafts are cholesterol-and sphingolipid-enriched microdomains in cell membranes that regulate phosphorylation cascades originating from membrane-bound proteins. In this study, we tested whether alteration of the cholesterol content of lipid rafts in prostate cancer (PCa) cell membranes affects cell survival mechanisms in vitro and in vivo. Simvastatin, a cholesterol synthesis inhibitor, lowered raft cholesterol content, inhibited Akt1 serine-threonine kinase (protein kinase Bα)/protein kinase B (Akt/PKB) pathway signaling, and induced apoptosis in caveolin-and PTEN-negative LNCaP PCa cells. Replenishing cell membranes with cholesterol reversed these inhibitory and apoptotic effects. Cholesterol also potentiated Akt activation in normal prostate epithelial cells, which were resistant to the apoptotic effects of simvastatin. Elevation of circulating cholesterol in SCID mice increased the cholesterol content and the extent of protein tyrosine phosphorylation in lipid rafts isolated from LNCaP/sHB xenograft tumors. Cholesterol elevation also promoted tumor growth, increased phosphorylation of Akt, and reduced apoptosis in the xenografts. Our results implicate membrane cholesterol in Akt signaling in both normal and malignant cells and provide evidence that PCa cells can become dependent on a cholesterol-regulated Akt pathway for cell survival.

show abstract

“…4A, evidenced that SKF86002 partially prevented ROS-induced increases in Hyal activity (91 Ϯ 24 versus 35 Ϯ 15%). To further examine if p38MAPK activation was sufficient to induce Hyal2 mRNA expression, we treated NHBE cells with the p38MAPK activator LPC (45). …”

Section: Ros-induced Hyal Activity Is Mediated By P38mapkmentioning

confidence: 99%

Reactive Oxygen Species and Hyaluronidase 2 Regulate Airway Epithelial Hyaluronan Fragmentation

Monzón

Fregien

Schmid

et al. 2010

Journal of Biological Chemistry

100

View full text Add to dashboard Cite

Hyaluronidase 2 (Hyal2) is a hyaluronan (HA)-degrading enzyme found intracellularly or/and anchored to the plasma membrane through glycosylphosphatidylinositol (GPI). Normal human bronchial epithelial cells (NHBE) grown at the air-liquid interphase (ALI), treated with PI-specific phospholipase C (PI-PLC), exhibited increased Hyal activity in secretions and decreased protein and activity on the apical membrane, confirming that GPI-anchored Hyal2 is expressed in NHBE cells and it remains active in its soluble form. We have reported that HA degradation was mediated by reactive oxygen species (ROS) in human airways. Here we show that ROS increase Hyal2 expression and activity in NHBE cells and that the p38MAPK signaling pathway is involved in this effect. Hyal2 induction was confirmed by using small interfering RNA (siRNA) expressing lentivirus. These in vitro findings correlated in vivo with smokers, where increased Hyal2 immunoreactivity in the epithelium was associated with augmented levels of HA and the appearance of low molecular mass HA species in bronchial secretions. In summary, this work provides evidence that ROS induce Hyal2, suggesting that Hyal2 is likely responsible for the sustained HA fragmentation in the airway lumen observed in inflammatory conditions associated with oxidative stress. Hyaluronan (HA)3 is a non-sulfated glycosaminoglycan found in the extracellular matrix, in body fluids, and in secretions of mammals. HA is synthesized by three transmembrane isoenzymes: HAS1, HAS2, and HAS3 at the inner face of the plasma membrane and translocated into the extracellular space (1).The association with various binding proteins (2, 3) confers HA with a unique plasticity to organize extracellular matrix (ECM) in a tissue specific fashion (for review see Ref. 4), varying from a tightly cross-linked mesh in cartilage to a highly hydrated matrix in dermis and vitreous humor (5).In addition, HA induces intracellular signaling by binding specific receptors at the cell surface, (6, 7) orchestrating a variety of host responses generally requiring an extensive deposition of a HA in the ECM. This deposition is essential for cumulus oophorus fertilization (8) as well as for proliferation and migration of mesenchymal cells. Airway smooth muscle cells exposed to polyinosinic acid-polycytidylic acid synthesize an abnormal HA matrix with cable-like structures that bind and retains leukocytes (9, 10), suggesting that HA play key roles on host defense against infections as well.Biological functions of HA are associated with its size (6, 11). For instance, high molecular weight HA (HMWHA) exhibit anti-angiogenic, anti-inflammatory, and immunosuppressive effects while small HA fragments are angiogenic and proinflammatory (12, 13). The contrasting responses elicited by different sizes of HA are exemplified in a recent report in which HMWHA attenuated while low molecular weight HA (LMWHA) increased ozone-induced airway hyperreactivity, in a mouse model of asthma (14).In human airway epithelium, HA is present at the lumen as...

show abstract

Lysophosphatidylcholine activates mesangial cell PKC and MAP kinase by PLCγ-1 and tyrosine kinase-Ras pathways

Cited by 44 publications

References 39 publications

The Mood Stabilizer Valproic Acid Activates Mitogen-activated Protein Kinases and Promotes Neurite Growth

The Mood Stabilizer Valproic Acid Activates Mitogen-activated Protein Kinases and Promotes Neurite Growth

Cholesterol targeting alters lipid raft composition and cell survival in prostate cancer cells and xenografts

Reactive Oxygen Species and Hyaluronidase 2 Regulate Airway Epithelial Hyaluronan Fragmentation

Contact Info

Product

Resources

About