scholarly journals Aldosterone rapidly activates p-PKC delta and GPR30 but suppresses p-PKC epsilon protein levels in rat kidney

2019 ◽  
Vol 53 (3) ◽  
pp. 154-164 ◽  
Author(s):  
Somchit Eiam-Ong ◽  
Mookda Chaipipat ◽  
Krissanapong Manotham ◽  
Somchai Eiam-Ong
Keyword(s):  
Rat Kidney ◽  
Kidney Cortex ◽  
Protein Abundance ◽  
Protein Levels ◽  
Pkc Delta ◽  
Pkc Epsilon ◽  
Male Wistar Rats ◽  
Pkc Alpha

AbstractObjectives. Aldosterone rapidly enhances protein kinase C (PKC) alpha and beta1 proteins in the rat kidney. The G protein-coupled receptor 30 (GPR30)-mediated PKC pathway is involved in the inhibition of the potassium channel in HEK-239 cells. GPR30 mediates rapid actions of aldosterone in vitro. There are no reports available regarding the aldosterone action on other PKC isoforms and GPR30 proteins in vivo. The aim of the present study was to examine rapid actions of aldosterone on protein levels of phosphorylated PKC (p-PKC) delta, p-PKC epsilon, and GPR30 simultaneously in the rat kidney.Methods. Male Wistar rats were intraperitoneally injected with normal saline solution or aldosterone (150 µg/kg body weight). After 30 minutes, abundance and immunoreactivity of p-PKC delta, p-PKC epsilon, and GPR30 were determined by Western blot analysis and immunohisto-chemistry, respectively.Results. Aldosterone administration significantly increased the renal protein abundance of p-PKC delta by 80% (p<0.01) and decreased p-PKC epsilon protein by 50% (p<0.05). Aldosterone injection enhanced protein immunoreactivity of p-PKC delta but suppressed p-PKC epsilon protein intensity in both kidney cortex and medulla. Protein abundance of GPR30 was elevated by aldosterone treatment (p<0.05), whereas the immunoreactivity was obviously changed in the kidney cortex and inner medulla. Aldosterone translocated p-PKC delta and GPR30 proteins to the brush border membrane of proximal convoluted tubules.Conclusions. This is the first in vivo study simultaneously demonstrating that aldosterone administration rapidly elevates protein abundance of p-PKC delta and GPR30, while p-PKC epsilon protein is suppressed in rat kidney. The stimulation of p-PKC delta protein levels by aldosterone may be involved in the activation of GPR30.

scholarly journals Rapid Nongenomic Action of Aldosterone on Protein Expressions of Hsp90(αandβ) and pc-Src in Rat Kidney

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Somchit Eiam-Ong ◽  
Kittisak Sinphitukkul ◽  
Krissanapong Manotham ◽  
Somchai Eiam-Ong
Keyword(s):  
Rat Kidney ◽  
Growth Factor Receptor ◽  
Heat Shock Protein 90 ◽  
Protein Levels ◽  
Nongenomic Action ◽  
Luminal Membrane ◽  
Protein Expressions ◽  
Male Wistar Rats

Previousin vitrostudies indicated that aldosterone nongenomically phosphorylates epidermal growth factor receptor (EGFR) through activation of upstream signals, heat shock protein 90β(Hsp90β), and cytosolic (c)-Src kinase. We demonstrated that aldosterone rapidly elevates EGFR phosphorylation in rat kidney. There are noin vivodata regarding renal Hsp90(αandβ) and phosphorylated (p)c-Src protein expressions. The present study further investigates the expressions of these proteins. Male Wistar rats were intraperitoneally injected with normal saline solution or aldosterone (Aldo: 150 μg/kg BW). After 30 minutes, abundances and localizations of these proteins were determined. Aldosterone enhanced renal Hsp90βprotein abundance (P<0.001), but Hsp90αand pc-Src protein levels remained unaltered. Expression of Hsp90(αandβ) was induced prominently in the proximal convoluted tubules (PCTs). Activation of Hsp90αwas observed in vascular and outer medulla regions, whereas Hsp90βwas induced in the cortex. Immunoreactivity of pc-Src was elevated in PCT with obvious staining at the luminal membrane. Thisin vivostudy is the first to demonstrate that aldosterone nongenomically elevates Hsp90(αandβ) protein expressions in rat kidney. Aldosterone had no effect on pc-Src protein levels but modulated localization. These results indicate that aldosterone regulates upstream mediators of EGFR transactivationin vivo.

scholarly journals Rapid Action of Aldosterone on Protein Levels of Sodium-Hydrogen Exchangers and Protein Kinase C Beta Isoforms in Rat Kidney

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Somchit Eiam-Ong ◽  
Mookda Chaipipat ◽  
Krissanapong Manotham ◽  
Somchai Eiam-Ong
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Rat Kidney ◽  
Protein Abundance ◽  
Renal Vasculature ◽  
Protein Levels ◽  
Kinase C ◽  
Sodium Hydrogen

Previous in vitro studies demonstrated that aldosterone rapidly activates sodium-hydrogen exchangers 1 and 3 (NHE 1 and 3). In vitro investigations revealed that protein kinase C (PKC) regulates NHE properties. We previously demonstrated that aldosterone rapidly enhances PKCα protein abundance in the rat kidney. There are no reports of renal PKCβ (I and II) protein levels related to the regulation by aldosterone. There are also no in vivo data regarding the rapid effects of aldosterone on renal protein levels of NHE (1 and 3) and PKCβ (I and II), simultaneously. In the current study, rats received normal saline solution or aldosterone (150 μg/kg BW, i.p.). After 30 minutes, abundance and immunoreactivity of these proteins were determined by Western blot analysis and immunohistochemistry, respectively. Aldosterone increased NHE1 and NHE3 protein abundance to 152% and 134%, respectively (P<0.05). PKCβI protein level was enhanced by 30%, whereas PKCβII declined slightly. Aldosterone increased NHE protein expression mostly in the medulla. PKCβI immunostaining intensity was increased in the glomeruli, renal vasculature, and thin limb of the loop of Henle, while PKCβII was reduced. This is the first in vivo study to simultaneously demonstrate that aldosterone rapidly elevates PKCβI and NHE (1 and 3) protein abundance in the rat kidney. Aldosterone-induced NHE (1 and 3) protein levels may be related to PKCβI activation.

Effect of experimentally induced hypothyroidism on sulfate renal transport in rats

1999 ◽  
Vol 276 (1) ◽  
pp. F164-F171 ◽  
Author(s):  
Kazuko Sagawa ◽  
Heini Murer ◽  
Marilyn E. Morris
Keyword(s):  
Sodium Sulfate ◽  
Basolateral Membrane ◽  
Kidney Cortex ◽  
Renal Transport ◽  
Sulfate Anion ◽  
Protein Levels ◽  
Serum Sulfate ◽  
Hypothyroid Patients

Decreased serum sulfate concentrations are observed in hypothyroid patients. However, the mechanism involved in thyroid hormone-induced alterations of renal sulfate homeostasis is unknown. The objectives of this investigation were to determine the effect of 6-propyl-2-thiouracil (PTU)-induced hypothyroidism in rats on 1) the in vivo serum concentrations, renal clearance, and renal reabsorption of sulfate, 2) the in vitro renal transport in brush-border membrane (BBM) and basolateral membrane (BLM) vesicles, and 3) the cellular mechanism of the hypothyroid-induced alteration in sulfate renal transport. Serum sulfate concentrations, renal fractional reabsorption of sulfate, and creatinine clearance were decreased significantly in the hypothyroid group. The V max values for sodium-sulfate cotransport in BBM were significantly decreased in the kidney cortex from the hypothyroid animals (0.90 ± 0.31 vs. 0.49 ± 0.08 nmol ⋅ mg−1 ⋅ 10 s−1, n = 5–6, P < 0.05) without changes in K m. There were no significant differences in V max and K m for sulfate/anion exchange transport in BLM. Sodium-dependent sulfate transporter (NaSi-1) mRNA and protein levels were significantly lower in the kidney cortex from hypothyroid rats. Hypothyroidism did not alter the membrane motional order (fluidity) in BBM and BLM, which indicates that the changes in the membrane fluidity do not represent the mechanism for the altered renal transport. These results demonstrate that PTU-induced hypothyroidism decreases sodium-sulfate cotransport by downregulation of the NaSi-1 gene.

Regulation of sgk by aldosterone and its effects on the epithelial Na+ channel

2000 ◽  
Vol 278 (4) ◽  
pp. F613-F619 ◽  
Author(s):  
Alexander Shigaev ◽  
Carol Asher ◽  
Hedva Latter ◽  
Haim Garty ◽  
Eitan Reuveny
Keyword(s):  
De Novo ◽  
Rat Kidney ◽  
Kidney Cortex ◽  
Na Channel ◽  
Xenopus Laevis Oocytes ◽  
Fourfold Increase ◽  
Tight Epithelia ◽  
High Level

Aldosterone is the major corticosteroid regulating Na+ absorption in tight epithelia and acts primarily by activating the epithelial Na+ channel (ENaC) through unknown induced proteins. Recently, it has been reported that aldosterone induces the serum- and glucocorticoid-dependent kinase sgk and that coexpressing ENaC with this kinase in Xenopus laevis oocytes increases the amiloride-sensitive Na+current (Chen SY, Bhargava A, Mastroberardino L, Meijer OC, Wang J, Buse P, Firestone GL, Verrey F, and Pearce D. Proc Natl Acad Sci USA 96: 2514–2519, 1999). The present study was done to further characterize regulation of sgk by aldosterone in native mammalian epithelia and to examine its effect on ENaC. With both in vivo and in vitro protocols, an almost fivefold increase in the abundance of sgk mRNA has been demonstrated in rat kidney and colon but not in lung. Induction of sgk by aldosterone was detected in kidney cortex and medulla, whereas the papilla expressed a constitutively high level of the kinase. The increase in sgkmRNA was detected as early as 30 min after the hormonal application and was independent of de novo protein synthesis. The observed aldosterone dose-response relationships suggest that the response is mediated, at least in part, by occupancy of the mineralocorticoid receptor. Coexpressing sgk and ENaC in Xenopus oocytes evoked a fourfold increase in the amiloride-blockable Na+ channel activity. A point mutation in the β-subunit known to impair regulation of the channel by Nedd4 (Y618A) had no significant effect on the response to sgk.

scholarly journals Accumulation of Sulfate by Mitochondria of Rat Kidney Cortex

1962 ◽  
Vol 45 (4) ◽  
pp. 757-775 ◽  
Author(s):  
Robert W. Winters ◽  
Adelaide M. Delluva ◽  
Ingrith J. Deyrup ◽  
Robert E. Davies
Keyword(s):  
Rat Kidney ◽  
Kidney Cortex ◽  
Ph Optimum ◽  
Rat Kidney Cortex ◽  
Sulfate Ions ◽  
Straight Line ◽  
Freundlich Adsorption Isotherm ◽  
Ambient Concentrations

Twice washed mitochondria from rat kidney cortex can accumulate sulfate ions from low (10-7 M) ambient concentrations to create virtual gradients of several hundred to one. This sulfate is subsequently released. The activation energy for the uptake is 12,000 calories per mole; for release it is about 30,000 calories per mole. Variations in the sulfate concentration of the medium show that there is a straight line Freundlich adsorption isotherm over a million-fold range of concentration of sulfate in the medium. There are 9 x 104 sites at 10-5 M and 9 x 105 sites at 10-3 M sulfate per average single mitochondrion. Preincubation at 30°C rapidly destroys the ability to accumulate sulfate. Partial protection occurs if oxidative phosphorylation is proceeding during the preincubation. The concentration of the endogenous inorganic sulfate of twice washed mitochondria is 4.2 x 10-4 moles per liter of mitochondrial pellet water; 99.85 per cent of this endogenous sulfate is inexchangeable with external sulfate in vitro. It is all exchangeable in vivo. The pH optimum for accumulation of radiosulfate from dilute external sulfate concentrations is 5.5. These observations show that there is a delicate and specific mechanism in mitochondria from kidney cortex which accumulates sulfate. The chemical nature of the accumulated sulfate is unknown.

Identification of aldo-keto reductase (AKR7A1) and glutathione S-transferase pi (GSTP1) as novel renal damage biomarkers following exposure to mercury

2018 ◽  
Vol 37 (10) ◽  
pp. 1025-1036 ◽  
Author(s):  
Y-J Shin ◽  
K-A Kim ◽  
E-S Kim ◽  
J-H Kim ◽  
H-S Kim ◽  
...  
Keyword(s):  
Rat Kidney ◽  
Dependent Manner ◽  
Clinical Markers ◽  
Sprague Dawley ◽  
Glutathione S Transferase ◽  
Protein Levels ◽  
Kidney Proximal Tubular Cells ◽  
New Biomarkers

The kidney is one of the main targets for toxicity induced by xenobiotics. Sensitive detection of early impairment is critical to assess chemical-associated renal toxicity. The aim of this study was to identify potential nephrotoxic biomarkers in rat kidney tissues after exposure to mercury (Hg), a representative nephrotoxicant, and to evaluate these new biomarkers employing in vivo and in vitro systems. Mercuric chloride was administered orally to Sprague-Dawley rats for 2 weeks. Proteomic analysis revealed that aldo-keto reductase (AKR7A1) and glutathione S-transferase pi (GSTP1) were significantly elevated in kidney after Hg exposure. While the levels of conventional nephrotoxic clinical markers including blood urea nitrogen and serum creatinine were not elevated, the mRNA and protein levels of AKR7A1 and GSTP1 were increased upon Hg exposure in a dose-dependent manner. The increases in AKR7A1 and GSTP1 were also observed in rat kidneys after an extended exposure for 6 weeks to low-dose Hg. In in vitro rat kidney proximal tubular cells, changes in AKR7A1 and GSTP1 levels correlated well with the extent of cytotoxicity induced by Hg, cadmium, or cisplatin. AKR7A1 and GSTP1 were identified as new candidates for Hg-induced nephrotoxicity, suggesting that these biomarkers have potential for evaluating or predicting nephrotoxicity.

scholarly journals 3-Mercaptopicolinic acid, an inhibitor of gluconeogenesis

1974 ◽  
Vol 138 (3) ◽  
pp. 387-394 ◽  
Author(s):  
N. W. DiTullio ◽  
C. E. Berkoff ◽  
B. Blank ◽  
V. Kostos ◽  
E. J. Stack ◽  
...  
Keyword(s):  
Rat Kidney ◽  
Diabetic Rats ◽  
Kidney Cortex ◽  
Hepatic Glycogen ◽  
Hypoglycaemic Effect ◽  
Rat Kidney Cortex ◽  
Urea Production ◽  
Rat Livers

1. 3-Mercaptopicolinic acid (SK&F 34288) inhibited gluconeogenesis in vitro, with lactate as substrate, in rat kidney-cortex and liver slices. 2. In perfused rat livers, gluconeogenesis was inhibited when lactate, pyruvate or alanine served as substrate, but not with fructose, suggesting pyruvate carboxylase or phosphoenolpyruvate carboxylase as the site of inhibition. No significant effects were evident in O2 consumption, hepatic glycogen, urea production, or [lactate]/[pyruvate] ratios. 3. A hypoglycaemic effect was evident in vivo in starved and alloxan-diabetic rats, starved guinea pigs and starved mice, but not in 4h-post-absorptive rats. 4. In the starved rat the hypoglycaemia was accompanied by an increase in blood lactate. 5. A trace dose of [14C]lactate in vivo was initially oxidized to a lesser extent in inhibitor-treated rats, but during 90min the total CO2 evolved was slightly greater. The total amount of the tracer oxidized was not significantly different from that in the controls.

scholarly journals Insulin increases mRNA levels of protein kinase C-α and -β in rat adipocytes and protein kinase C-α, -β and -θ in rat skeletal muscle

1995 ◽  
Vol 308 (1) ◽  
pp. 181-187 ◽  
Author(s):  
A Avignon ◽  
M L Standaert ◽  
K Yamada ◽  
H Mischak ◽  
B Spencer ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Mrna Levels ◽  
Rat Adipocytes ◽  
Kinase C ◽  
Pkc Epsilon ◽  
Pkc Alpha

Effects of insulin of levels of mRNA encoding protein kinase C (PKC)-alpha, PKC-beta, PKC-epsilon and PKC-theta were examined by ribonuclease protection assay in primary cultures of rat adipocytes in vitro, and in rat adipose tissue and gastrocnemius muscle in vivo. In all cases, insulin increased the levels of PKC-alpha mRNA and PKC-beta mRNA, and, in muscle, insulin also increased the level of PKC-theta mRNA. PKC-epsilon mRNA levels, on the other hand, were not altered significantly. Insulin also stimulated the apparent translocation of PKC-alpha, -beta, -epsilon and -theta, to the membrane fractions of adipocytes, adipose tissue and gastrocnemius muscles, and, in some instances, total PKC levels were diminished, e.g. PKC-alpha and PKC-beta in cultured adipocytes in vitro and/or whole adipose tissue in vivo, and PKC-alpha and PKC-theta in the gastrocnemius muscle. Thus, insulin-induced increases in PKC mRNA may have been partly compensatory in nature to restore PKC levels following translocation and proteolytic losses. However, much more severe depletion of PKC-alpha and PKC-beta by phorbol ester treatment in cultured rat adipocytes in vitro resulted in, if anything, smaller increases in PKC-alpha mRNA and PKC-beta mRNA, and it therefore appears that insulin effects on PKC mRNA levels were not simply due to decreases in respective PKC levels. In addition, effects of insulin, particularly on PKC-beta mRNA, could not be attributed to increased glucose metabolism, which alone decreased PKC-beta mRNA in cultured adipocytes in vitro. We conclude that insulin-induced translocation and degradation of PKC-alpha, PKC-beta and PKC-theta are attended by selective increases in their mRNAs. This mechanism of increasing mRNA may be important in maintaining PKC levels during the continued action of insulin.

scholarly journals Effects of insulin on the translocation of protein kinase C-θ and other protein kinase C isoforms in rat skeletal muscles

1995 ◽  
Vol 308 (1) ◽  
pp. 177-180 ◽  
Author(s):  
K Yamada ◽  
A Avignon ◽  
M L Standaert ◽  
D R Cooper ◽  
B Spencer ◽  
...  
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Skeletal Muscles ◽  
Phorbol Esters ◽  
Kinase C ◽  
Pkc Epsilon ◽  
Pkc Isoforms ◽  
Pkc Alpha

Protein kinase C (PKC)-theta is a newly recognized major PKC isoform in skeletal muscle. In this study we found that insulin provoked rapid biphasic increases in membrane-associated immunoreactive PKC-theta, as well as PKC-alpha, PKC-beta and PKC-epsilon, in rat soleus muscles incubated in vitro. Effects of insulin on PKC isoforms in the soleus were comparable in magnitude with those of phorbol esters. Increases in membrane-associated PKC-theta, PKC-alpha, PKC-beta and PKC-epsilon were also observed in rat gastrocnemius muscles after insulin treatment in vivo. Our findings suggest that PKC-theta, like other diacylglycerol-sensitive PKC isoforms (alpha, beta and epsilon), may play a role in insulin action in skeletal muscles.

Attenuation of CCl4-induced hepatic fibrosis by GdCl3treatment or dietary glycine

2001 ◽  
Vol 281 (1) ◽  
pp. G200-G207 ◽  
Author(s):  
C. A. Rivera ◽  
B. U. Bradford ◽  
K. J. Hunt ◽  
Y. Adachi ◽  
L. W. Schrum ◽  
...  
Keyword(s):  
Kupffer Cell ◽  
Kupffer Cells ◽  
Cell Activation ◽  
Transforming Growth Factor ◽  
Stellate Cell ◽  
Smooth Muscle Actin ◽  
Protein Levels ◽  
Male Wistar Rats

The role of Kupffer cells in CCl4-induced fibrosis was investigated in vivo. Male Wistar rats were treated with phenobarbital and CCl4for 9 wk, and a group of rats were injected with the Kupffer cell toxicant gadolinium chloride (GdCl3) or were fed glycine, which inactivates Kupffer cells. After CCl4alone, the fibrosis score was 3.0 ± 0.1 and collagen protein and mRNA expression were elevated, but GdCl3or glycine blunted these parameters. Glycine did not alter cytochrome P-450 2E1, making it unlikely that glycine affects CCl4metabolism. Treatment with GdCl3or glycine prevented CCl4-induced increases in transforming growth factor (TGF)-β1 protein levels and expression. CCl4treatment increased α-smooth muscle actin staining (score 3.0 ± 0.2), whereas treatment with GdCl3and glycine during CCl4exposure blocked this effect (1.2 ± 0.5); there was no staining with glycine treatment. These results support previous in vitro data and demonstrate that treatment of rats with the selective Kupffer cell toxicant GdCl3prevents stellate cell activation and the development of fibrosis.

Sign in / Sign up

Export Citation Format

Share Document