Dataset Information

Akt and ERK1/2 pathways are components of the vasopressin signaling network in rat native IMCD.

ABSTRACT: Vasopressin regulates water excretion through effects on the renal collecting duct. Vasopressin signaling in the inner medullary collecting duct (IMCD) is mediated by V2 receptor occupation coupled to the generation of cyclic AMP. Here, we employ a "systems" approach to analysis of vasopressin signaling. The objective is to investigate roles of activation of the Akt and ERK1/2 MAP kinase pathways, as well as Ca2+ mobilization, in IMCD cells isolated from rat kidney. The V2 receptor-selective vasopressin analog dDAVP increased the state of Akt activation (increased phosphorylation at T308 and S473) and decreased the state of ERK1/2 activation (decreased phosphorylation at T202 and Y204). Akt activation was blocked by an inhibitor of PI3K, LY294002. In microdissected IMCD segments, nonperiodic spike-like increases in intracellular Ca2+ (FLUO-4) were accelerated by vasopressin. Chelation of Ca2+ or calmodulin inhibition markedly decreased Akt phosphorylation. Decreased ERK1/2 phosphorylation was associated with a decrease in MEK1/2 phosphorylation and an increase in c-Raf phosphorylation at S259 (an inhibitory site). Based on the current findings integrated with previous findings in the IMCD, we now report a 33-node vasopressin signaling network involved in vasopressin regulation of IMCD function.

SUBMITTER: Pisitkun T

PROVIDER: S-EPMC2574714 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Akt and ERK1/2 pathways are components of the vasopressin signaling network in rat native IMCD.

Pisitkun Trairak T Jacob Vinitha V Schleicher Stephen M SM Chou Chung-Lin CL Yu Ming-Jiun MJ Knepper Mark A MA

American journal of physiology. Renal physiology 20080730 4

Vasopressin regulates water excretion through effects on the renal collecting duct. Vasopressin signaling in the inner medullary collecting duct (IMCD) is mediated by V2 receptor occupation coupled to the generation of cyclic AMP. Here, we employ a "systems" approach to analysis of vasopressin signaling. The objective is to investigate roles of activation of the Akt and ERK1/2 MAP kinase pathways, as well as Ca2+ mobilization, in IMCD cells isolated from rat kidney. The V2 receptor-selective vas ...[more]

PMID: 18667481

Similar Datasets

Project description:Quantitative mass spectrometry was used to identify hormone-dependent signaling pathways in renal medullary thick ascending limb (mTAL) cells via phosphoproteomic analysis. Active transport of NaCl across the mTAL epithelium is accelerated by hormones that increase cAMP levels (vasopressin, glucagon, parathyroid hormone, and calcitonin). mTAL suspensions from rat kidneys were exposed (15 min) to a mixture of these four hormones. Tryptic phosphopeptides (immobilized metal affinity chromatography-enriched) were identified and quantified by mass spectrometry (LTQ-Orbitrap) using label-free methodology. We quantified a total of 654 phosphopeptides, of which 414 were quantified in three experimental pairs (hormone vs. vehicle). Of these phosphopeptides, 82% were statistically unchanged in abundance in response to the hormone mixture. In contrast, 48 phosphopeptides were significantly increased, whereas 28 were significantly decreased. The population of up-regulated phosphopeptides was highly enriched in basophilic kinase substrate motifs (AGC or calmodulin-sensitive kinase families), whereas the down-regulated sites were dominated by "proline-directed" motifs (cyclin-dependent or MAP kinase families). Bioinformatic classification uncovered overrepresentation of transmembrane transporters, protein phosphatase regulators, and cytoskeletal binding proteins among the regulated proteins. Immunoblotting with phospho-specific antibodies confirmed cAMP/vasopressin-dependent phosphorylation at Thr96, Ser126, and Ser874 of the Na(+):K(+):2Cl(-) cotransporter NKCC2, at Ser552 of the Na(+):H(+) exchanger NHE3, and at Ser552 of beta-catenin. Vasopressin also increased phosphorylation of NKCC2 at both Ser126 (more than fivefold) and Ser874 (more than threefold) in rats in vivo. Both sites were phosphorylated by purified protein kinase A during in vitro assays. These results support the view that, although protein kinase A plays a central role in mTAL signaling, additional kinases, including those that target proline-directed motifs, may be involved.

Project description:BackgroundHuanglianjiedu decoction (HLJDD) is a classical Traditional Chinese Medicine (TCM) prescription with thousand years of clinical use against various malignancies, including pancreatic adenocarcinoma (PAAD). However, its potential bioactive component and molecular mechanism remains unclear.AimsThis study is to inspect the HLJDD mechanisms of action against PAAD via integrated computational and pharmacochemistry strategy, in vivo and in vitro experiments to validate associated targets and pathways.MethodsA PAAD xenograft model was established by subcutaneous injecting Panc02 cells into C57BL/6 mice. Ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) was engaged to determine constituents of HLJDD and assessed for pharmacokinetic scheme using the TCM Systems Pharmacology Platform (TCM-SP). Differentially expressed genes (DEGs) of PAAD was retrieved from the transcriptome dataset GSE43795, followed by recognizing overlapping targets the oncogenes and target genes of PAAD and HLJDD, respectively. Putative signaling pathways of HLJDD in treating PAAD were enriched using KEGG and GO analyses. The anti-PAAD effects of HLJDD was assessed in vivo and in vitro, besides, the potential mechanism was validated using immunoblotting and immunohistochemical assays.ResultsHLJDD significantly suppressed the growth of transplanted PAAD tumors, constrained PAAD progression, and induced apoptosis and S-phase arrest. Seventy-five active components meeting the drug-likeness criteria and 278 target genes of HLJDD were identified. KEGG analysis indicated that the top three enriched pathways were cancer, AGE-RAGE signaling, and IL-17 signaling pathways. Disease enrichment analysis highlighted immune, pharmacological, and cancer-related diseases as the top three categories. A total of 47 potential target genes were identified. Immunoblotting revealed that HLJDD inhibited PI3K and MAPK-related signaling pathways, while immunohistochemical staining confirmed that HLJDD suppressed the expression of phosphorylated MAPK and ERK1/2.ConclusionHLJDD inhibited PAAD in vitro and in vivo via the modulation of multiple mechanisms, including regulation of PI3K/AKT/mTOR and MAPK/ERK1/2 signaling pathways.

Dataset Information

Akt and ERK1/2 pathways are components of the vasopressin signaling network in rat native IMCD.

Publications

Akt and ERK1/2 pathways are components of the vasopressin signaling network in rat native IMCD.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets