AGEs induce oxidative stress and activate protein  kinase C-βII in neonatal mesangial cells

Increased activation of specific protein kinase C (PKC) isoforms and increased nonenzymatic glycation of intracellular and extracellular proteins [the accumulation of advanced glycation end products (AGEs)] are major mechanistic pathways implicated in the pathogenesis of diabetic complications. Blocking PKC-βII has been shown to decrease albuminuria in animal models of diabetes. To demonstrate a direct relationship between AGEs and the induction and translocation of PKC-βII, studies were carried out in rat neonatal mesangial cells, known to express PKC-βII in association with rapid proliferation in post-natal development. Oxidative stress was studied by using the fluorescent probe dichlorfluorescein diacetate. Translocation of PKC-βII was demonstrated by using immunofluorescence and Western blotting of fractionated mesangial cells. Induction of intracellular oxidative stress, increase in intracellular calcium, and cytosol to membrane PKC-βII translocation (with no change in PKC-α) were demonstrated after exposure to AGE-rich proteins. These data support the hypothesis that AGEs cause mesangial oxidative stress and alterations in PKC-βII, changes that may ultimately contribute to phenotypic abnormalities associated with diabetic nephropathy.

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PDGF and IL-1 induce and activate specific protein kinase C isoforms in mesangial cells

AJP Renal Physiology ◽

10.1152/ajprenal.1996.271.1.f108 ◽

1996 ◽

Vol 271 (1) ◽

pp. F108-F113 ◽

Cited By ~ 6

Author(s):

M. B. Ganz ◽

B. Saksa ◽

R. Saxena ◽

K. Hawkins ◽

J. R. Sedor

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

De Novo ◽

Mesangial Cells ◽

De Novo Synthesis ◽

Kinase C ◽

Pkc Isoforms ◽

Alpha Beta ◽

Pkc Alpha

In vitro and in vivo data suggest a remarkable plasticity in the differentiated phenotype of intrinsic glomerular cells, which after injury express new structures and functions. We have shown that a protein kinase C (PKC) isoform, beta II, is expressed in diseased but not normal glomeruli. Since intrarenal cytokine synthesis has been implicated in the pathogenesis of progressive glomerular injury, we have hypothesized that these mediators induce a change in isoform profile. To test this hypothesis in vitro, we have determined whether platelet-derived growth factor (PDGF) and interleukin-1 (IL-1) alter the expression or activation of PKC isoforms in cultured mesangial cells (MCs). By immunoblot and ribonuclease (RNase) protection assays, both PDGF and IL-1 induce as early as 2 h de novo synthesis of PKC-beta II. Since MCs constitutively express PKC-alpha, -beta I, and -zeta, we also determined whether IL-1 or PDGF alter the activity of these isoforms. PDGF maximally induced translocation of PKC-alpha (10 min), -beta I (90 min), -epsilon (120 min), and -zeta (120 min) from the cytosolic to the membrane fraction. IL-1, in contrast, did not alter the distribution of alpha, beta I, or epsilon at any time measured but did induce PKC-zeta translocation. These data suggest inflammatory mediators regulate PKC isoform activity in diseased glomeruli both by de novo synthesis of unexpressed isoforms and by activation of constitutively expressed PKC isoforms.

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Acetylcholine Activates Protein Kinase C-α in Pulmonary Venous Smooth Muscle

Anesthesiology ◽

10.1097/00000542-200703000-00015 ◽

2007 ◽

Vol 106 (3) ◽

pp. 507-514 ◽

Cited By ~ 4

Author(s):

Xueqin Ding ◽

Paul A. Murray

Keyword(s):

Smooth Muscle ◽

Protein Kinase C ◽

Protein Kinase ◽

Pulmonary Veins ◽

Specific Protein ◽

Isometric Tension ◽

Kinase C ◽

Pkc Isoforms ◽

Pkc Alpha ◽

Pkc Iota

Background The authors investigated whether acetylcholine-induced contraction in pulmonary venous smooth muscle (PVSM) is associated with the activation of specific protein kinase C (PKC) isoforms. Methods Isolated canine pulmonary venous rings without endothelium were suspended in modified Krebs-Ringer's buffer for measurement of isometric tension. The effects of nonspecific PKC inhibition (bisindolylmaleimide I; 3 x 10 m) and conventional PKC isoform inhibition (Gö7936 10 m) on the acetylcholine dose-response relation were assessed. The expression of conventional PKC isoforms (alpha, beta, gamma), novel PKC isoforms (delta, epsilon, theta), and atypical PKC isoforms (zeta, iota, mu) was measured in PVSM cells by Western blot analysis. The immunofluorescence technique and confocal microscopy were used to localize the cellular distribution of PKC isoforms before and after the addition of acetylcholine. Results Acetylcholine caused dose-dependent contraction in E-pulmonary veins. Pretreatment with bisindolylmaleimide I or Gö7936 attenuated acetylcholine contraction. PKC-alpha, -iota, -mu, and -zeta were expressed, whereas PKC-beta, -gamma, -delta, -epsilon;, and -theta were not expressed in PVSM cells. Immunofluorescence staining for PKC isoforms showed that in unstimulated cells, PKC-alpha and PKC-mu were detected only in the cytoplasm. PKC-iota and PKC-zeta also exhibited a cytoplasmic immunofluorescence pattern, which was especially abundant in the perinuclear zone. Activation with acetylcholine induced translocation of PKC-alpha from cytoplasm to membrane, whereas acetylcholine had no effect on the other PKC isoforms. Translocation of PKC-alpha in response to acetylcholine was blocked by the muscarinic receptor antagonist, atropine. Conclusion Acetylcholine contraction is attenuated by PKC inhibition in PVSM. Acetylcholine induces translocation of PKC-alpha from cytoplasm to membrane in PVSM. These results suggest that PKC-dependent acetylcholine contraction in PVSM may involve activation and translocation of PKC-alpha.

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EXPRESSION OF SPECIFIC PROTEIN KINASE C (PKC) ISOFORMS AND LIGAND-SPECIFIC ACTIVATION OF PKCα IN LATE GESTATION FETAL LUNG

Experimental Lung Research ◽

10.1080/01902140701385073 ◽

2007 ◽

Vol 33 (3-4) ◽

pp. 185-196 ◽

Cited By ~ 4

Author(s):

Dina Villanueva-García ◽

Karen T. Wang ◽

Heber C. Nielsen ◽

Sujatha M. Ramadurai

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Fetal Lung ◽

Specific Protein ◽

Late Gestation ◽

Kinase C ◽

Pkc Isoforms ◽

Specific Protein Kinase

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Amino acids injure mesangial cells by advanced glycation end products, oxidative stress, and protein kinase C

Kidney International ◽

10.1111/j.1523-1755.2005.00159.x ◽

2005 ◽

Vol 67 (3) ◽

pp. 953-968 ◽

Cited By ~ 28

Author(s):

Katherine R. Tuttle ◽

Emily C. Johnson ◽

Sheryl K. Cooney ◽

Robert J. Anderberg ◽

Edward K. Johnson ◽

...

Keyword(s):

Oxidative Stress ◽

Amino Acids ◽

Protein Kinase C ◽

Protein Kinase ◽

Advanced Glycation End Products ◽

Mesangial Cells ◽

Advanced Glycation ◽

Kinase C ◽

Glycation End Products ◽

End Products

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Selective modulation of specific protein kinase C (PKC) isoforms in primary human megakaryocytic vs. erythroid cells

The Anatomical Record ◽

10.1002/(sici)1097-0185(19990501)255:1<7::aid-ar2>3.0.co;2-t ◽

1999 ◽

Vol 255 (1) ◽

pp. 7-14 ◽

Cited By ~ 10

Author(s):

Marco Marchisio ◽

Valeria Bertagnolo ◽

Claudio Celeghini ◽

Marco Vitale ◽

Silvano Capitani ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Specific Protein ◽

Erythroid Cells ◽

Kinase C ◽

Pkc Isoforms ◽

Selective Modulation ◽

Specific Protein Kinase

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Contribution of protein kinase C to ET-1-induced proliferation in human myometrial cells

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1999.276.3.e503 ◽

1999 ◽

Vol 276 (3) ◽

pp. E503-E511 ◽

Cited By ~ 2

Author(s):

C. Tertrin-Clary ◽

I. Eude ◽

T. Fournier ◽

B. Paris ◽

M. Breuiller-Fouché ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Tyrosine Kinase ◽

Protein Tyrosine Kinase ◽

Myometrial Cells ◽

Kinase C ◽

Pkc Isoforms ◽

Pkc Β ◽

Pkc Ζ ◽

Tyrphostin 23

The role of protein kinase C (PKC) in endothelin-1 (ET-1)-induced proliferation of human myometrial cells was investigated. ET-1 dose dependently stimulated DNA synthesis and the number of cultured myometrial cells. Inhibition of PKC by calphostin C or Ro-31-8220 or downregulation of PKC eliminated the proliferative effects of ET-1. The failure of two protein tyrosine kinase (PTK) inhibitors (tyrphostin 51 and tyrphostin 23) to affect ET-1-induced proliferation supports the hypothesis of noninvolvement of the tyrosine kinase signaling pathway in this process. The expression and distribution of PKC isoforms were examined by Western blot analysis. The five PKC isoforms (PKC-α, -β1, -β2, -ζ, -ε) evidenced in human myometrial tissue were found to be differentially expressed in myometrial cells, with a predominant expression of PKC-α and PKC-ζ. Treatment with phorbol 12,13-dibutyrate (PDBu) resulted in the translocation of all five isoforms to the particulate fraction, whereas ET-1 induced a selective increase in particulate PKC-β1, PKC-β2, and PKC-ε. Our findings that multiple PKC isoforms are differentially responsive to ET-1 or PDBu suggest that they play distinct roles in the myometrial growth process.

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NK-active cytokines IL-2, IL-12, and IL-15 selectively modulate specific protein kinase C (PKC) isoforms in primary human NK cells

The Anatomical Record ◽

10.1002/ar.10039 ◽

2002 ◽

Vol 266 (2) ◽

pp. 87-92 ◽

Cited By ~ 28

Author(s):

Marco Vitale ◽

Alessandra Bassini ◽

Paola Secchiero ◽

Prisco Mirandola ◽

Cristina Ponti ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Nk Cells ◽

Specific Protein ◽

Kinase C ◽

Pkc Isoforms ◽

Specific Protein Kinase

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Mesangial cell protein kinase C isozyme activation in the diabetic milieu

AJP Renal Physiology ◽

10.1152/ajprenal.00014.2002 ◽

2002 ◽

Vol 282 (6) ◽

pp. F975-F980 ◽

Cited By ~ 74

Author(s):

Catharine I. Whiteside ◽

John A. Dlugosz

Keyword(s):

Diabetic Nephropathy ◽

Protein Kinase C ◽

Protein Kinase ◽

High Glucose ◽

Mesangial Cell ◽

Mesangial Cells ◽

Cell Protein ◽

Kinase C ◽

Pkc Β ◽

Vasoactive Peptide

High-glucose-induced activation of mesangial cell protein kinase C (PKC) contributes significantly to the pathogenesis of diabetic nephropathy. Excess glucose metabolism through the polyol pathway leads to de novo synthesis of both diacylglyerol (DAG) and phosphatidic acid, which may account for increased mesangial cell PKC-α, -β, -δ, -ε, and -ζ activation/translocation observed within 48-h exposure to high glucose. Raised intracellular glucose causes generation of reactive oxygen species that may directly activate PKC isozymes and enhance their reactivity to vasoactive peptide signaling. In both diabetic rodent models of diabetes and cultured mesangial cells, PKC-β appears to be the key isozyme required for the enhanced expression of transforming growth factor-β1, initiation of early accumulation of mesangial matrix protein, and increased microalbuminuria. Enhanced collagen IV expression by mesangial cells in response to vasoactive peptide hormone stimulation, e.g., endothelin-1, requires PKC-β, -δ, -ε and -ζ. Loss of mesangial cell contractility to potent vasoactive peptides and coincident F-actin disassembly are due to high-glucose-activation of PKC-ζ. Inhibition of mesangial cell PKC isozyme activation in high glucose may prove to be the next important treatment for diabetic nephropathy.

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