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1.
Balkan Med J ; 38(6): 331-340, 2021 11.
Article in English | MEDLINE | ID: mdl-34860160

ABSTRACT

BACKGROUND: Previous studies have published the promoting effect of serum and glucocorticoid-regulated kinase 1 (SGK1) in various malignant tumors. However, whether SGK1 promotes gastric cancer remains a mystery. AIMS: To clarify the function of SGK1 in gastric cancer and its potential regulatory mechanism. STUDY DESIGN: Cell culture study. METHODS: The SGK1-silenced model was generated in two gastric cancer cell lines and further evaluated their malignant behavior and susceptibility to cisplatin. The interaction between miR-15a-5p and SGK1 was evaluated by the luciferase reporter assay. The knockdown efficiency of SGK1 was confirmed by RT- qPCR and Western blot assays. Cell proliferation rate was assessed with CCK-8 assay, and flow cytometry was used to determine cell cycle progression and apoptosis. RESULTS: Western blot data displayed an elevated level of SGK1 in gastric cancer cell lines. Functionally, SGK1 deficiency suppressed gastric cancer cell proliferation (P < .01) by acting on cell-cycle progression. Moreover, SGK1 deficiency suppressed cell invasion and migration of gastric cancer cells (P < .01). Further, the silencing of SGK1 obviously suppressed cell proliferation and induced apoptosis of the cells after cisplatin treatment (P < .01), indicating that SGK1 deficiency facilitated the chemosensitivity of these 2 gastric cancer cell lines to cisplatin. Mechanically, downregulation of SGK1 repressed the cytoplasm- to-nucleus translocation of NF-κB p65. Interestingly, we found that miR-15a-5p binds to the 3'UTR of SGK1, which was confirmed using luciferase activity assay (P < .05). Moreover, the data suggested that SGK1 reversed the suppression effect of miR-15a-5p on gastric cancer cell migration (P < .01). CONCLUSION: Loss of SGK1 suppresses the malignant behavior of gastric cancer cells and increases cisplatin sensitivity by restraining the NF-κB signaling pathway. Moreover, SGK1 may exert an inhibitory effect in gastric cancer by being targeted by miR-15a-5p. Therefore, SGK1 may be a prospective target for future gastric cancer therapy.


Subject(s)
Cisplatin/pharmacology , Immediate-Early Proteins/blood , NF-kappa B/genetics , Protein Serine-Threonine Kinases/blood , Stomach Neoplasms/drug therapy , Blotting, Western , Cisplatin/therapeutic use , Glucocorticoids , Humans , MicroRNAs/genetics , Prospective Studies , Real-Time Polymerase Chain Reaction , Signal Transduction , Stomach Neoplasms/blood , Stomach Neoplasms/genetics
2.
J ECT ; 36(2): 137-143, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31725056

ABSTRACT

OBJECTIVES: Hypothalamic-pituitary-adrenal axis dysregulation is frequently observed in patients with depression, with increased levels of the glucocorticoid (GC) cortisol commonly reported. Hypothalamic-pituitary-adrenal axis dysregulation may be a consequence of impaired feedback inhibition due to GC receptor (GR) impairments or dysfunction, termed "glucocorticoid resistance." Here, our objective was to assess mRNA levels of GC-related markers (GR, FKBP5, serum glucocorticoid kinase 1 [SGK1]) in patients with depression versus controls and in patient samples after electroconvulsive therapy (ECT). We also examined the relationship between these GC-related markers and 24-item Hamilton Depression Rating Scale (HAM-D24) scores to assess the utility of using them as biological markers for depression or the therapeutic response to ECT. METHODS: GR, FKBP5, and SGK1 mRNA levels were examined in whole blood samples from 88 medicated patients with depression pre-/post-ECT and 63 controls using quantitative real-time polymerase chain reaction. Exploratory subgroup correlational analyses were performed to determine the relationship between GR, FKBP5, and SGK1 and 24-item Hamilton Depression Rating Scale scores. RESULTS: GR, FKBP5, and SGK1 mRNA levels were significantly lower in medicated patients with depression compared with controls (P < 0.001, P = 0.03, P < 0.001, respectively), but ECT did not alter their levels (all P > 0.05). There was no relationship between GR, FKBP5, or SGK1 and 24-item Hamilton Depression Rating Scale scores. CONCLUSIONS: GR, FKBP5, and SGK1 do not seem to be involved in the peripheral molecular response to ECT and do not represent useful biomarkers for predicting the therapeutic response to ECT in a real-world clinical setting.


Subject(s)
Depressive Disorder, Major/blood , Depressive Disorder, Major/therapy , Electroconvulsive Therapy , Immediate-Early Proteins/blood , Protein Serine-Threonine Kinases/blood , Receptors, Glucocorticoid/blood , Tacrolimus Binding Proteins/blood , Adult , Affect , Aged , Biomarkers/blood , Depressive Disorder, Major/drug therapy , Female , Humans , Male , Middle Aged , Psychiatric Status Rating Scales , RNA, Messenger/blood , Treatment Outcome
3.
Clin Cancer Res ; 25(2): 629-640, 2019 01 15.
Article in English | MEDLINE | ID: mdl-30322876

ABSTRACT

PURPOSE: The molecular events that determine intestinal cell differentiation are poorly understood and it is unclear whether it is primarily a passive event or an active process. It is clinically important to gain a greater understanding of the process, because in colorectal cancer, the degree of differentiation of a tumor is associated with patient survival. SGK1 has previously been identified as a gene that is principally expressed in differentiated intestinal cells. In colorectal cancer, there is marked downregulation of SGK1 compared with normal tissue.Experimental Design: An inducible SGK1 viral overexpression system was utilized to induce reexpression of SGK1 in colorectal cancer cell lines. Transcriptomic and phenotypic analyses of these colorectal cancer lines was performed and validation in mouse and human cohorts was performed. RESULTS: We demonstrate that SGK1 is upregulated in response to, and an important controller of, intestinal cell differentiation. Reexpression of SGK1 in colorectal cancer cell lines results in features of differentiation, decreased migration rates, and inhibition of metastasis in an orthotopic xenograft model. These effects may be mediated, in part, by SGK1-induced PKP3 expression and increased degradation of MYC. CONCLUSIONS: Our results suggest that SGK1 is an important mediator of differentiation of colorectal cells and may inhibit colorectal cancer metastasis.


Subject(s)
Colorectal Neoplasms/blood , Colorectal Neoplasms/pathology , Immediate-Early Proteins/blood , Protein Serine-Threonine Kinases/blood , Animals , Biomarkers, Tumor , Cell Differentiation , Cell Line, Tumor , Cell Proliferation , Colorectal Neoplasms/genetics , Colorectal Neoplasms/mortality , Disease Models, Animal , Female , Gene Expression , Genes, Reporter , Humans , Immediate-Early Proteins/genetics , Mice , Neoplasm Grading , Neoplasm Metastasis , Prognosis , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , RNA, Messenger , Rats , Signal Transduction , Xenograft Model Antitumor Assays
4.
JCI Insight ; 2(22)2017 11 16.
Article in English | MEDLINE | ID: mdl-29202451

ABSTRACT

Three Akt isoforms, encoded by 3 separate genes, are expressed in mammals. While the roles of Akt1 and Akt2 in metabolism are well established, it is not yet known whether Akt3 plays a role in metabolic diseases. We now report that Akt3 protects mice from high-fat diet-induced obesity by suppressing an alternative pathway of adipogenesis via with no lysine protein kinase-1 (WNK1) and serum/glucocorticoid-inducible kinase 1 (SGK1). We demonstrate that Akt3 specifically phosphorylates WNK1 at T58 and promotes its degradation via the ubiquitin-proteasome pathway. A lack of Akt3 in adipocytes increases the WNK1 protein level, leading to activation of SGK1. SGK1, in turn, promotes adipogenesis by phosphorylating and inhibiting transcription factor FOXO1 and, subsequently, activating the transcription of PPARγ in adipocytes. Akt3-deficient mice have an increased number of adipocytes and, when fed a high-fat diet, display increased weight gain, white adipose tissue expansion, and impaired glucose homeostasis. Pharmacological blockade of SGK1 in high-fat diet-fed Akt3-deficient mice suppressed adipogenesis, prevented excessive weight gain and adiposity, and ameliorated metabolic parameters. Thus, Akt3/WNK1/SGK1 represents a potentially novel signaling pathway controlling the development of obesity.


Subject(s)
Adipogenesis/drug effects , Immediate-Early Proteins/metabolism , Obesity/prevention & control , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Signal Transduction/drug effects , WNK Lysine-Deficient Protein Kinase 1/metabolism , 3T3-L1 Cells , Adipocytes/metabolism , Adipocytes/pathology , Adipose Tissue, White/metabolism , Adipose Tissue, White/pathology , Animals , Diet, High-Fat/adverse effects , Disease Models, Animal , Female , Forkhead Box Protein O1/metabolism , Glucose/metabolism , Homeostasis , Immediate-Early Proteins/antagonists & inhibitors , Immediate-Early Proteins/blood , Male , Mice , Mice, Knockout , PPAR gamma/metabolism , Phosphorylation , Proteasome Endopeptidase Complex/metabolism , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/blood , Proto-Oncogene Proteins c-akt/genetics , Transcription Factors/drug effects , Ubiquitin/metabolism , WNK Lysine-Deficient Protein Kinase 1/blood , Weight Gain
5.
Cell Physiol Biochem ; 38(4): 1532-43, 2016.
Article in English | MEDLINE | ID: mdl-27050729

ABSTRACT

BACKGROUND/AIMS: Expression of the transcriptional co-regulator tis7 is markedly increased in the adaptive small intestine in a mouse model of short bowel syndrome. Transgenic mice with enterocytic overexpression of tis7 (tis7tg) have accelerated triglyceride absorption, with increased adiposity yet reduced skeletal muscle mass. To further explore this phenotype, we examined whether tis7 also regulates amino acid and carbohydrate absorption. METHODS: Small intestinal glucose and amino acid uptake were quantified in wild type (WT) and tis7tg mice. Amino acid transporter expression was assessed by qRT-PCR and immunoblot. Apical cell surface transporter expression was quantified by cell surface biotinylation. RESULTS: Active glucose uptake rates were unchanged. Uptake of proline but not leucine was significantly reduced in tis7tg vs. WT jejunum. Expression of serum and glucocorticoid-induced kinase 1 (SGK1), a solute carrier activator, was inhibited in tis7tg jejunum. Apical membrane expression of the proline transporter SLC6A20 was reduced in tis7tg jejunum. CONCLUSIONS: Tis7 overexpression in enterocytes inhibits proline uptake, associated with decreased expression of activated SGK1 and reduced cell surface expression of SLC6A20. Consistent with the observed tis7tg phenotype, tis7 overexpression increases triglyceride absorption but has adverse effects on the uptake of selected amino acids. Tis7 has pleiotropic effects on nutrient absorption.


Subject(s)
Immediate-Early Proteins/metabolism , Jejunum/metabolism , Membrane Proteins/metabolism , Proline/metabolism , Protein Serine-Threonine Kinases/metabolism , Amino Acid Transport Systems/genetics , Amino Acid Transport Systems/metabolism , Animals , Blotting, Western , Body Weight , Diet, High-Fat , Glucose/metabolism , Immediate-Early Proteins/blood , Immediate-Early Proteins/genetics , Membrane Proteins/genetics , Mice , Mice, Transgenic , Phosphorylation , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction
6.
J Neurochem ; 138(2): 354-61, 2016 07.
Article in English | MEDLINE | ID: mdl-27123541

ABSTRACT

Increased expression of serum- and glucocorticoid-inducible kinase 1 (SGK1) can be induced by stress and growth factors in mammals, and plays an important role in cancer, diabetes, and hypertension. A recent work suggested that SGK1 activity restores damage in a stroke model. To further investigate the role of SGKs in ischemic brain injury, we examined how SGK inhibitors influence stroke outcome in vivo and neurotoxicity in vitro. Infarct volumes were compared in adult mice with middle cerebral artery occlusion, followed by 24 h reperfusion, in the absence or presence of SGK inhibitors. Neurotoxicity assay, electrophysiological recording, and fluorescence Ca(2+) imaging were carried out using cultured cortical neurons to evaluate the underlying mechanisms. Contrary to our expectation, infarct volume by stroke decreased significantly when SGK inhibitor, gsk650394, or EMD638683, was administrated 30 min before middle cerebral artery occlusion under normal and diabetic conditions. SGK inhibitors reduced neurotoxicity mediated by N-methyl-D-aspartate (NMDA) receptors, a leading factor responsible for cell death in stroke. SGK inhibitors also ameliorated Ca(2+) increase and peak amplitude of NMDA current in cultured neurons. In addition, SGK inhibitor gsk650394 decreased phosphorylation of Nedd4-2 and inhibited voltage-gated sodium currents. These observations suggest that SGK activity exacerbates stroke damage and that SGK inhibitors may be useful candidates for therapeutic intervention. To investigate the role of serum- and glucocorticoid-inducible kinases (SGKs) in ischemic brain injury, we examined how SGK inhibitors influence stroke outcome. Infarct volumes induced by middle cerebral artery occlusion were decreased significantly by SGK inhibitors. The inhibitors also reduced glutamate toxicity, at least partly, by attenuation of NMDA and voltage-gated sodium currents. Thus, SGK inhibition attenuates stroke damage.


Subject(s)
Glucocorticoids/pharmacology , Immediate-Early Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Stroke/metabolism , Animals , Benzamides/pharmacology , Hydrazines/pharmacology , Immediate-Early Proteins/antagonists & inhibitors , Immediate-Early Proteins/blood , Infarction, Middle Cerebral Artery/drug therapy , Male , Mice, Inbred C57BL , Protein Serine-Threonine Kinases/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/metabolism , Stroke/drug therapy , Ubiquitin-Protein Ligases/metabolism
7.
Fertil Steril ; 105(5): 1266-1273, 2016 05.
Article in English | MEDLINE | ID: mdl-26827666

ABSTRACT

OBJECTIVE: To determine the expression and biological roles of serum and glucocorticoid-regulated kinase (SGK1) in tissues and cells from patients with endometriosis and from healthy control subjects. DESIGN: Case-control. SETTING: University research setting. PATIENT(S): Premenopausal women. INTERVENTION(S): Endometriotic tissues were obtained from women with ovarian endometriosis, and normal endometrial tissues were obtained from women undergoing hysterectomy for benign conditions. MAIN OUTCOME MEASURE(S): Expression levels of SGK1, the role of SGK1 in endometriosis pathology, and regulation of SGK1 by estrogen receptor (ER) ß. RESULT(S): Transcript and protein levels of SGK1 were significantly higher in endometriotic tissues and cells compared with normal endometrium. SGK1 mRNA and protein levels were stimulated by E2, by the ERß-selective agonist diarylpropionitrile, and by prostaglandin E2. SGK1 was transcriptionally regulated by ERß based on small interfering RNA knockdown and chromatin immunoprecipitation of ERß followed by quantitative polymerase chain reaction. SGK1 knockdown led to increased cleavage of poly(ADP-ribose) polymerase, and SGK1 activation was correlated with the phosphorylation of FOXO3a, a proapoptotic factor. CONCLUSION(S): ERß leads to SGK1 overexpression in endometriosis, which contributes to the survival of endometriotic lesions through inhibition of apoptosis.


Subject(s)
Endometriosis/blood , Endometrium/cytology , Endometrium/enzymology , Estrogen Receptor beta/physiology , Immediate-Early Proteins/blood , Protein Serine-Threonine Kinases/blood , Biomarkers/blood , Biomarkers/metabolism , Case-Control Studies , Cell Survival/physiology , Endometriosis/metabolism , Endometriosis/pathology , Endometrium/pathology , Enzyme Activation/physiology , Female , Humans , Immediate-Early Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism
8.
J Atheroscler Thromb ; 22(9): 981-98, 2015.
Article in English | MEDLINE | ID: mdl-25958931

ABSTRACT

AIM: The circulating RNA levels are predictive markers in several diseases. We determined the levels of circulating p53-related genes in patients with acute ST-segment elevation myocardial infarction (STEMI), indicating major heart muscle damage. METHODS: Plasma RNA was extracted from the patients (n=45) upon their arrival to the hospital (STEMI 0h) and at four hours post-catheterization (STEMI 4h) as well as from controls (n=34). RESULTS: Of 18 circulating p53-related genes, nine genes were detectable. A significantly lower incidence of circulating p21 (p < 0.0001), Notch1 (p=0.042) and BTG2 (p < 0.0001) was observed in the STEMI 0h samples in comparison to the STEMI 4h and control samples. Lower expression levels (2.1-fold) of circulating BNIP3L (p=0.011), p21 (3.4-fold, p=0.005) and BTG2 (6.3-fold, p=0.0001) were observed in the STEMI 0h samples in comparison to the STEMI 4h samples, with a 7.4-fold lower BTG2 expression (p < 0.001) and 2.6-fold lower p21 expression (p=0.034) compared to the control samples. Moreover, the BNIP3L expression (borderline significance, p=0.0655) predicted the level of peak troponin, a marker of myocardial infarction. In addition, the BNIP3L levels on admission (p=0.0025), at post-catheterization (p=0.020) and the change between the groups (p=0.0079) were inversely associated with troponin. The BNIP3L (p=0.0139) and p21 levels (p=0.0447) were also associated with a longer time to catheterization. CONCLUSIONS: Our results suggest that circulating downstream targets of p53 are inhibited during severe AMI and subsequently re-expressed after catheterization, uncovering possible novel death-or-survival decisions regarding the fate of p53 in the heart and the potential use of its target genes as prognostic biomarkers for oxygenation normalization.


Subject(s)
Gene Expression Regulation , Genes, p53 , Myocardial Infarction/blood , Myocardial Infarction/genetics , RNA/blood , Tumor Suppressor Protein p53/genetics , Acute Disease , Adult , Aged , Aged, 80 and over , Area Under Curve , Cyclin-Dependent Kinase Inhibitor p21/blood , Cyclin-Dependent Kinase Inhibitor p21/genetics , Gene Expression Profiling , Humans , Immediate-Early Proteins/blood , Immediate-Early Proteins/genetics , Incidence , Male , Membrane Proteins/blood , Membrane Proteins/genetics , Middle Aged , Myocardial Infarction/epidemiology , Oxygen/chemistry , Percutaneous Coronary Intervention , Perfusion , Prognosis , Proto-Oncogene Proteins/blood , Proto-Oncogene Proteins/genetics , Receptor, Notch1/blood , Receptor, Notch1/genetics , Tumor Suppressor Proteins/blood , Tumor Suppressor Proteins/genetics
9.
J Thromb Haemost ; 13(7): 1325-34, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25944668

ABSTRACT

BACKGROUND: Platelet secretion is critical to development of acute thrombotic occlusion. Platelet dense granules contain a variety of important hemostatically active substances. Nevertheless, biogenesis of platelet granules is poorly understood. OBJECTIVES: Serum- and glucocorticoid-inducible kinase 1 (SGK1) has been shown to be highly expressed in platelets and megakaryocytes, but its role in the regulation of platelet granule biogenesis and its impact on thrombosis has not been investigated so far. METHODS AND RESULTS: Electron microscopy analysis of the platelet ultrastructure revealed a significant reduction in the number and packing of dense granules in platelets lacking SGK1 (sgk1(-/-) ). In sgk1(-/-) platelets serotonin content was significantly reduced and activation-dependent secretion of ATP, serotonin and CD63 significantly impaired. In vivo adhesion after carotis ligation was significantly decreased in platelets lacking SGK1 and occlusive thrombus formation after FeCl3 -induced vascular injury was significantly diminished in sgk1(-/-) mice. Transcript levels and protein abundance of dense granule biogenesis regulating GTPase Rab27b were significantly reduced in sgk1(-/-) platelets without affecting Rab27b mRNA stability. In MEG-01 cells transfection with constitutively active (S422) (D) SGK1 but not with inactive (K127) (N) SGK1 significantly enhanced Rab27b mRNA levels. Sgk1(-/-) megakaryocytes show significantly reduced expression of Rab27b and serotonin/CD63 levels compared with sgk1(+/+) megakaryocytes. Proteome analysis identified nine further vesicular transport proteins regulated by SGK1, which may have an impact on impaired platelet granule biogenesis in sgk1(-/-) platelets independent of Rab27b. CONCLUSIONS: The present observations identify SGK1 as a novel powerful regulator of platelet dense granule biogenesis, platelet secretion and thrombus formation. SGK1 is at least partially effective because it regulates transcription of Rab27b in megakaryocytes.


Subject(s)
Blood Platelets/enzymology , Carotid Artery Injuries/enzymology , Cytoplasmic Granules/enzymology , Immediate-Early Proteins/blood , Platelet Activation , Protein Serine-Threonine Kinases/blood , Secretory Vesicles/enzymology , Thrombosis/enzymology , Adenosine Triphosphate/blood , Adenosine Triphosphate/metabolism , Animals , Blood Platelets/metabolism , Blood Platelets/ultrastructure , Carotid Artery Injuries/blood , Carotid Artery Injuries/genetics , Carotid Artery Injuries/pathology , Cells, Cultured , Cytoplasmic Granules/metabolism , Cytoplasmic Granules/ultrastructure , Disease Models, Animal , Female , Genotype , Immediate-Early Proteins/deficiency , Immediate-Early Proteins/genetics , Male , Megakaryocytes/enzymology , Megakaryocytes/metabolism , Mice, Knockout , Phenotype , Platelet Aggregation , Protein Serine-Threonine Kinases/deficiency , Protein Serine-Threonine Kinases/genetics , RNA, Messenger/metabolism , Secretory Vesicles/metabolism , Secretory Vesicles/ultrastructure , Serotonin/blood , Serotonin/metabolism , Signal Transduction , Tetraspanin 30/blood , Tetraspanin 30/metabolism , Thrombosis/blood , Thrombosis/genetics , Thrombosis/pathology , Time Factors , Transfection , Up-Regulation , rab GTP-Binding Proteins/genetics , rab GTP-Binding Proteins/metabolism
10.
Pediatr Transplant ; 19(2): 196-205, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25515054

ABSTRACT

IRI of a transplanted heart may result in serious early and late disadvantageous effects such as increased allograft immunogenicity, primary graft dysfunction, and initiation of fibroproliferative cascades that compromise the survival of the recipient. Sgk-1 has recently been linked to cell growth and survival. It has been reported that through a renal transplantation model, Dexa increases Sgk-1 expression and therefore protects from renal IRI. In our current study, we aim to assess the expression of Sgk-1 and its protective effects on cardiomyocyte IRI after heart transplantation. Heart allograft model was performed from Wistar into Lewis, and isograft model was from Lewis into Lewis. Grafts were then harvested at one, six, 12, or 24 h post-transplantation for Sgk-1 expression analyses. In some groups, part donors were treated with Dexa 2 h prior at doses of 0.05, 0.5 and 2 mg/BWkg, respectively. Sgk-1 expression was markedly increased in grafted heart 6-12 h post-transplantation in both the allogenic and isogenic models. Immunostaining experiments confirmed that Sgk-1 was expressed in cardiomyocytes rather than infiltrated immune cells. Furthermore, Dexa treatment significantly increased Sgk-1 expression and the donor cardiomyocyte injury was greatly minimized by Dexa treatment. These results suggest that induction of Sgk-1 might explain some of the beneficial impact of corticosteroids in IRI and hence might have therapeutic implications.


Subject(s)
Gene Expression Regulation, Enzymologic , Heart Failure/surgery , Heart Transplantation , Immediate-Early Proteins/blood , Immediate-Early Proteins/metabolism , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/metabolism , Adrenal Cortex Hormones/chemistry , Allografts , Animals , Cell Proliferation , Dexamethasone/chemistry , Graft Survival , Male , Myocytes, Cardiac/cytology , Myocytes, Cardiac/metabolism , Rats , Rats, Inbred Lew , Rats, Wistar , Reperfusion Injury , Transplantation, Homologous
11.
Nephrology (Carlton) ; 19(6): 307-17, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24602173

ABSTRACT

AIM: Serum- and glucocorticoid-inducible kinase SGK1 functions as an important regulator of transepithelial sodium transport by activating epithelial sodium channel in renal tubules. Considerable evidence demonstrated that SGK1 was associated with hypertension and fibrosing diseases, such as diabetic nephropathy and glomerulonephritis. The present study was performed to evaluate the role of SGK1 played in immunoglobulin A (IgA) nephropathy. METHODS: Seventy-six patients of biopsy-proven IgA nephropathy and 33 healthy volunteers were enrolled in this study. All patients and healthy volunteers' urinary and serum samples were tested for SGK1 expression by indirect enzyme-linked immunosorbent assay. Meanwhile all patients' renal tissues were semi-quantified for SGK1 expression by immunohistochemistry assay. The relationships between SGK1 expressions and clinical or pathological parameters were also assessed. RESULTS: SGK1 expression was upregulated in urine and renal tubules in patients of Oxford classification T1 and T2, whereas its expression in serum did not increase significantly. Relationship analysis indicated that urinary and tissue SGK1 expressions were associated with heavy proteinuria and renal insufficiency in patients with IgA nephropathy. On the other hand, RAS blockades would reduce the SGK1 levels both in urine and renal tissues. CONCLUSION: These results suggested that urinary SGK1 should be a good indicator of tubulointerstitial damage in patients of IgA nephropathy. SGK1 expressions in urine and renal tissues were associated with the activity of renin-angiotensin-aldosterone system.


Subject(s)
Glomerulonephritis, IGA/metabolism , Immediate-Early Proteins/blood , Immediate-Early Proteins/urine , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/urine , Proteinuria/metabolism , Adult , Aged , Biomarkers/blood , Biomarkers/urine , Female , Glomerulonephritis, IGA/classification , Glomerulonephritis, IGA/drug therapy , Glucocorticoids/metabolism , Humans , Male , Middle Aged , Proteinuria/classification , Proteinuria/drug therapy , Renin-Angiotensin System/drug effects , Renin-Angiotensin System/physiology , Thiazides/therapeutic use , Young Adult
12.
Am J Physiol Cell Physiol ; 304(1): C49-55, 2013 Jan 01.
Article in English | MEDLINE | ID: mdl-23015548

ABSTRACT

Aggregation of the high-affinity IgE receptor (FcεRI) on mast cells (MCs) causes MC degranulation, a process that involves cortical F-actin disassembly. Actin depolymerization may be triggered by increase of cytosolic Ca(2+). Entry of Ca(2+) through the Ca(2+) release-activated Ca(2+) (CRAC) channels is under powerful regulation by the serum- and glucocorticoid-inducible kinase SGK1. Moreover, FcεRI-dependent degranulation is decreased in SGK1-deficient (sgk1(-/-)) MCs. The present study addressed whether SGK1 is required for actin cytoskeleton rearrangement in MCs and whether modulation of actin architecture could underlie decreased degranulation of sgk1(-/-) MCs. Confirming previous results, release of ß-hexosaminidase reflecting FcεRI-dependent degranulation was impaired in sgk1(-/-) MCs compared with sgk1(+/+) MCs. When CRAC channels were inhibited by 2-aminoethoxydiphenyl borate (2-APB; 50 µM), MC degranulation was strongly decreased in both sgk1(+/+) and sgk1(-/-) MCs and the difference between genotypes was abolished. Moreover, degranulation was impaired by actin-stabilizing (phallacidin) and enhanced by actin-disrupting (cytochalasin B) agents to a similar extent in sgk1(+/+) MCs and sgk1(-/-) MCs, implying a regulatory role of actin reorganization in this event. In line with this, measurements of monomeric (G) and filamentous (F) actin content by FACS analysis and Western blotting of detergent-soluble and -insoluble cell fractions indicated an increase of the G/F-actin ratio in sgk1(+/+) MCs but not in sgk1(-/-) MCs upon FcεRI ligation, an observation reflecting actin depolymerization. In sgk1(+/+) MCs, FcεRI-induced actin depolymerization was abolished by 2-APB. The observed actin reorganization was confirmed by confocal laser microscopic analysis. Our observations uncover SGK1-dependent Ca(2+) entry in mast cells as a novel mechanism regulating actin cytoskeleton.


Subject(s)
Actin Cytoskeleton/enzymology , Cell Degranulation/genetics , Glucocorticoids/physiology , Immediate-Early Proteins/metabolism , Mast Cells/enzymology , Protein Serine-Threonine Kinases/metabolism , Actin Cytoskeleton/drug effects , Actins/blood , Actins/metabolism , Animals , Bone Marrow Cells/cytology , Bone Marrow Cells/drug effects , Bone Marrow Cells/enzymology , Boron Compounds/pharmacology , Calcium/blood , Calcium/metabolism , Calcium Channels/blood , Cell Degranulation/drug effects , Cells, Cultured , Glucocorticoids/blood , Immediate-Early Proteins/blood , Immediate-Early Proteins/deficiency , Mast Cells/drug effects , Mast Cells/metabolism , Mice , Mice, Knockout , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/deficiency
13.
J Clin Endocrinol Metab ; 97(12): E2251-60, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23055545

ABSTRACT

CONTEXT: Using single-nucleotide polymorphism analysis, we observed allelic loss of the gene for serum glucocorticoid (GC) kinase 1 (SGK1), a GC-responsive kinase involved in multiple cellular functions, in a subset of cortisol-secreting adenomas. OBJECTIVE: Our objective was to analyze SGK1 expression in adrenocortical tumors and to further characterize its role in ACTH-independent cortisol secretion, tumor progression, and prognosis. DESIGN AND SETTING: Gene expression levels of SGK1, SGK3, and CTNNB1 (coding for ß-catenin) and protein expression levels of SGK1, nuclear ß-catenin, and phosphorylated AKT were determined in adrenocortical tumors and normal adrenal glands. PATIENTS: A total of 227 adrenocortical tumors (40 adenomas and 187 carcinomas) and 25 normal adrenal tissues were included. Among them, 62 frozen tumor samples were used for mRNA analysis and 203 tumors were investigated on tissue microarrays or full standard slides by immunohistochemistry. MAIN OUTCOME MEASURES: We evaluated the relationship between SGK1 mRNA and/or protein levels and clinical parameters. RESULTS: SGK1 mRNA levels were lower in cortisol-secreting than in nonsecreting tumors (P < 0.005). Nonsecreting neoplasias showed a significant correlation between SGK1 and CTNNB1 mRNA levels (P < 0.001; r = 0.57). Low SGK1 protein levels, but not nuclear ß-catenin and phosphorylated AKT, were associated with poor overall survival in patients with adrenocortical carcinoma (P < 0.005; hazard ratio = 2.0; 95% confidence interval = 1.24-3.24), independent of tumor stage and GC secretion. CONCLUSION: Low SGK1 expression is related to ACTH-independent cortisol secretion in adrenocortical tumors and is a new prognostic factor in adrenocortical carcinoma.


Subject(s)
Adrenal Cortex Neoplasms/diagnosis , Adrenal Cortex Neoplasms/genetics , Carcinoma/diagnosis , Carcinoma/genetics , Glucocorticoids/metabolism , Immediate-Early Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Adenoma/diagnosis , Adenoma/genetics , Adenoma/metabolism , Adenoma/mortality , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/mortality , Adrenocorticotropic Hormone/pharmacology , Adult , Biomarkers, Tumor/blood , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma/metabolism , Carcinoma/mortality , Female , Gene Expression Regulation, Neoplastic , Humans , Hydrocortisone/metabolism , Immediate-Early Proteins/blood , Immediate-Early Proteins/metabolism , Male , Middle Aged , Prognosis , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/metabolism , Survival Analysis
14.
J Clin Immunol ; 32(4): 809-19, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22371292

ABSTRACT

PURPOSE: Human cytomegalovirus (CMV) active infection (CMV infection) poses serious risks to CMV-seropositive heart transplant recipients. We evaluated the usefulness of simultaneous assessment of CMV-specific values for parameters of the humoral (antibodies) and cellular (CD4+ and CD8+ T-cells) immune responses in the identification of heart recipients at risk of developing CMV infection after transplantation. METHODS: We prospectively studied 38 CMV-seropositive heart recipients. Anti-CMV antibody titers were assessed using enzyme-linked immunosorbent assays. CD4+ and CD8+ T-cell responses to overlapping peptide pools of the CMV proteins pp65 and immediate early protein-1 (IE1) were evaluated by flow cytometry. Immunological studies were performed before transplantation and at 30 days after transplantation. Patients with CMV infection were compared with heart recipients without CMV infection. RESULTS: During the 6-month follow-up period, 13 (34.2%) patients developed CMV infection. At baseline, the mean anti-CMV-IgG antibody titer was lower in patients who developed CMV infection. This difference remained at 30 days after transplantation. One month after transplantation, the mean percentage of IE1-specific CD8+ T cells that are IFNg-positive (CD8/IFNg + IE1) was lower in CMV-infected patients. The predictive value of these variables at 30 days was increased when they were combined. Cox regression analysis revealed an association between the risk of developing CMV infection and the combination marker (low anti-CMV titer [<16,100] and low CD8/IFNg + IE1 percentages [<0.40%], relative hazard, 6.07; p = 0.019). The combination marker remained significant after adjustment for clinical variables. CONCLUSIONS: This novel approach of a simultaneous assessment of specific anti-CMV antibody titers and CD8/IFNg + IE1 percentages might help identify heart transplant recipients with an increased risk of developing CMV infection.


Subject(s)
Antibodies, Viral/blood , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cytomegalovirus Infections/immunology , Cytomegalovirus/immunology , Heart Transplantation/immunology , Adult , Aged , Biomarkers/blood , Cytomegalovirus Infections/virology , Female , Humans , Immediate-Early Proteins/blood , Immediate-Early Proteins/immunology , Male , Middle Aged , Phosphoproteins/blood , Phosphoproteins/immunology , Viral Matrix Proteins/blood , Viral Matrix Proteins/immunology , Young Adult
15.
Am J Psychiatry ; 168(1): 89-96, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21078706

ABSTRACT

OBJECTIVE: The development of posttraumatic stress disorder (PTSD) is influenced by preexisting vulnerability factors. The authors aimed at identifying a preexisting biomarker representing a vulnerability factor for the development of PTSD. To that end, they determined whether the dexamethasone binding capacity of leukocytes, as a measure of glucocorticoid receptor (GR) number, before exposure to trauma was a predictor of development of PTSD symptoms. In addition, the authors analyzed mRNA expression for GR subtypes and GR target genes. METHOD: Participants were selected from a large prospective study on deployment-related disorders, in which peripheral blood mononuclear cells (PBMCs) were obtained prior to and 1 and 6 months after military deployment. Participants included armed forces personnel with high levels of PTSD symptoms 6 months after deployment (N=34) and comparison subjects without high levels of PTSD or depressive symptoms (N=34) matched for age, rank, previous deployments, educational level, and function during deployment. RESULTS: Before military deployment, the GR number in PBMCs was significantly higher in participants who developed high levels of PTSD symptoms after deployment relative to matched comparison subjects. Logistic regression analysis showed that the risk for inclusion in the PTSD group after deployment increased 7.5-fold with each GR increase of 1,000. No group differences were observed in mRNA expression of GR-α, GR-P, GR-ß, glucocorticoid-induced leucine zipper (GILZ), serum and glucocorticoid-inducible kinase-1 (SGK-1), and FKBP5. The higher GR number in the PTSD group was maintained at 1 and 6 months after deployment. CONCLUSIONS: These results demonstrate that a preexisting high GR number in PBMCs is a vulnerability factor for subsequent development of PTSD symptoms.


Subject(s)
Military Personnel/psychology , Receptors, Glucocorticoid/blood , Stress Disorders, Post-Traumatic/blood , Stress Disorders, Post-Traumatic/diagnosis , Adult , Biomarkers/blood , Depression/blood , Humans , Hydrocortisone/blood , Immediate-Early Proteins/blood , Male , Protein Serine-Threonine Kinases/blood , Risk Factors , Self Report , Tacrolimus Binding Proteins/blood , Transcription Factors/blood
16.
Bone Marrow Transplant ; 45(3): 543-9, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19617905

ABSTRACT

Rising levels of cytomegalovirus (CMV) DNAemia and/or pp65 antigenemia have been observed during pre-emptive ganciclovir therapy in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT). We assessed the incidence of this event in our series, and investigated whether its occurrence was associated with an impairment in the CMV-specific T-cell response. A total of 36 allo-SCT recipients experienced one or more episodes of active CMV infection (n=68) that were pre-emptively treated with val(ganciclovir). Rising levels of antigenemia and DNAemia, and an isolated increase in antigenemia, were observed in 39.7 and 2.9% of all episodes, respectively. Receipt of corticosteroids was associated with rising levels of antigenemia and DNAemia. Median increases of 12- and 6.8-fold of IFNgamma CD8(+) T and IFNgamma CD4(+) T cells, respectively, were observed at a median of 16.5 days after initiation of therapy in episodes with decreasing levels in antigenemia and DNAemia. In contrast, the numbers of both T-cell subsets at a median of 13.5 days after initiation of therapy did not differ significantly from those of pre-treatment samples in episodes with rising levels of antigenemia and DNAemia. Lack of prompt expansion of CMV pp65 and IE-1-specific IFNgamma CD8(+) and CD4(+) T cells is associated with rising levels in antigenemia and DNAemia during pre-emptive therapy.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cytomegalovirus Infections/etiology , Cytomegalovirus Infections/immunology , Hematopoietic Stem Cell Transplantation/adverse effects , Adolescent , Adult , Aged , Antigens, Viral/blood , Cytomegalovirus/genetics , Cytomegalovirus/immunology , Cytomegalovirus/isolation & purification , Cytomegalovirus Infections/prevention & control , Cytomegalovirus Infections/virology , DNA, Viral/blood , Drug Resistance, Viral/genetics , Female , Ganciclovir/pharmacology , Humans , Immediate-Early Proteins/blood , Interferon-gamma/biosynthesis , Male , Middle Aged , Mutation , Opportunistic Infections/etiology , Opportunistic Infections/immunology , Opportunistic Infections/prevention & control , Opportunistic Infections/virology , Phosphoproteins/blood , Transplantation, Homologous , Viral Matrix Proteins/blood , Young Adult
17.
Curr Opin Nephrol Hypertens ; 18(5): 439-48, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19584721

ABSTRACT

PURPOSE OF REVIEW: The role of serum and glucocorticoid-inducible kinase 1 (SGK1) in renal physiology and pathophysiology is reviewed with particular emphasis on recent advances. RECENT FINDINGS: The mammalian target of rapamycin complex 2 has been shown to phosphorylate SGK1 at Ser422 (the so-called hydrophobic motif). Ser397 and Ser401 are two additional SGK1-phosphorylation sites required for maximal SGK1 activity. A 5' variant alternate transcript of human Sgk1 has been identified that is widely expressed and shows improved stability, enhanced membrane association, and greater stimulation of epithelial Na+ transport. SGK1 is essential for optimal processing of the epithelial sodium channel and also regulates the expression of the Na+-Cl- cotransporter. With regard to pathophysiology, SGK1 participates in the stimulation of renal tubular glucose transport in diabetes, the renal profibrotic effect of both angiotensin II and aldosterone, and in fetal programing of arterial hypertension. SUMMARY: The outlined recent findings advanced our understanding of the molecular regulation of SGK1 as well as the role of the kinase in renal physiology and the pathophysiology of renal disease and hypertension. Future studies using pharmacological inhibitors of SGK1 will reveal the utility of the kinase as a new therapeutic target.


Subject(s)
Immediate-Early Proteins/blood , Immediate-Early Proteins/physiology , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/physiology , Animals , Appetite/genetics , Appetite/physiology , Gene Expression Regulation, Enzymologic/physiology , Humans , Hypertension/enzymology , Hypertension/genetics , Immediate-Early Proteins/biosynthesis , Immediate-Early Proteins/genetics , Kidney/physiology , Metabolic Syndrome/enzymology , Metabolic Syndrome/genetics , Obesity/enzymology , Obesity/genetics , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/genetics
18.
Kidney Blood Press Res ; 32(2): 119-27, 2009.
Article in English | MEDLINE | ID: mdl-19401625

ABSTRACT

BACKGROUND/AIMS: Serum- and glucocorticoid-inducible kinase 1 (SGK1) stimulates the epithelial sodium channel (ENaC), renal outer medullary K(+) channel 1, Na(+)/K(+)-ATPase and presumably the Na(+)-Cl(-) cotransporter (NCC). SGK1-deficient mice (sgk(-/-)) show a compensated salt-losing phenotype with secondary hyperaldosteronism. The present experiments explored the role of SGK1 in the response to diuretics. METHODS: sgk1(-/-) mice and their wild-type littermates (sgk1(+/+)) were treated with the ENaC blocker triamterene (200 mg/l), the Na(+)-K(+)-2Cl(-) cotransport inhibitor furosemide (125 mg/l), the NCC blocker hydrochlorothiazide (400 mg/l) and the mineralocorticoid receptor blocker canrenoate (800 mg/l) for 8 days. Renal SGK1 expression was studied using quantitative RT-PCR and immunofluorescence. RESULTS: Diuretic treatment increased SGK1 mRNA and protein expression in the kidney of wild-type sgk1(+/+) mice. The responses to furosemide, hydrochlorothiazide or canrenoate were not different between sgk1(+/+) and sgk1(-/-) mice, and were accompanied by moderate increases in plasma aldosterone and urea concentrations. However, treatment with triamterene in sgk1(-/-) mice (but not in sgk1(+/+) mice) led to severe, eventually lethal, body weight loss as well as increases in plasma aldosterone, urea and K(+) concentrations. CONCLUSIONS: SGK1 is required for diuretic tolerance to triamterene. The observations confirm the impaired kaliuretic potency of sgk1(-/-) mice and point to a role of SGK1 in renal Na(+) reabsorption by mechanisms other than ENaC.


Subject(s)
Diuretics/pharmacology , Gene Targeting/methods , Immediate-Early Proteins/deficiency , Immediate-Early Proteins/genetics , Protein Serine-Threonine Kinases/deficiency , Protein Serine-Threonine Kinases/genetics , Animals , Drug Tolerance , Eating/drug effects , Eating/physiology , Epithelial Sodium Channels/physiology , Immediate-Early Proteins/blood , Mice , Mice, Inbred C57BL , Mice, Knockout , Protein Serine-Threonine Kinases/blood , Triamterene/pharmacology
19.
Article in Chinese | MEDLINE | ID: mdl-20108775

ABSTRACT

OBJECTIVE: This study was aimed to investigate the clinical value of Epstein-Barr virus (EBV) Rta/IgG in the diagnosis of nasopharyngeal carcinoma (NPC). METHODS: Serum samples derived from 211 untreated patients with NPC, 413 subjects including 203 non-NPC ENT patients and 210 healthy volunteers as control were examined for the presence of antibodies directed against Rta/IgG by using enzyme-linked immnunosorbent assay (ELISA). Receiver operating characteristic (ROC) curve was applied to perform methodical evaluation of this tumor marker. RESULTS: The rA value median of Rta/IgG in NPC group was significantly higher than one in control group (P < 0.001). The area under ROC was 0.933. The sensitivity and specificity of this marker were 90.5% and 90.1%, respectively, when the best cutoff value was defined. CONCLUSION: Rta/IgG detected with ELISA method is a new target of EBV, and may be one of important marker for NPC diagnosis.


Subject(s)
Antibodies, Viral/blood , Carcinoma/diagnosis , Diagnostic Tests, Routine/methods , Epstein-Barr Virus Infections/diagnosis , Herpesvirus 4, Human/immunology , Immediate-Early Proteins/immunology , Immunoglobulin G/blood , Nasopharyngeal Neoplasms/diagnosis , Trans-Activators/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma/blood , Carcinoma/immunology , Carcinoma/virology , Case-Control Studies , Child , Epstein-Barr Virus Infections/blood , Epstein-Barr Virus Infections/immunology , Epstein-Barr Virus Infections/virology , Female , Herpesvirus 4, Human/isolation & purification , Humans , Immediate-Early Proteins/blood , Male , Middle Aged , Nasopharyngeal Neoplasms/blood , Nasopharyngeal Neoplasms/immunology , Nasopharyngeal Neoplasms/virology , Trans-Activators/blood , Young Adult
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