IL-17A stimulates granulocyte colony-stimulating factor production via ERK1/2 but not p38 or JNK in human renal proximal tubular epithelial cells

We investigated the potential role of IL-17A in the induction of granulocyte colony-stimulating factor (G-CSF), a critical granulopoietic growth factor, in human renal proximal tubular epithelial cells. Human renal proximal tubular cells (HK-2, ATCC) were used to characterize the effects of IL-17A or IL-17F on G-CSF production, using ELISA, real-time RT-PCR, and immunoblotting. The cell surface expression of IL-17 receptors (IL-17Rs) was analyzed by flow cytometry. IL-17A stimulation of proximal tubular cells led to a dose- and time-dependent increase in secreted G-CSF. This effect was dependent on mRNA transcription and protein translation. Real-time RT-PCR demonstrated that G-CSF mRNA expression reached a maximum level at 6 h following IL-17A stimulation and that this increase was dose dependent. Both IL-17RA and IL-17RC were expressed on proximal tubular cells. IL-17A also enhanced TNF-α- or IL-1β-mediated G-CSF secretion from cells. Additionally, IL-17A induced MAPK (ERK1/2 but not p38 MAPK or JNK) activation, and pharmacological inhibitors of MEK1/2 (U0126) but not of p38 MAPK (SB203580) or JNK (SP600125), significantly blocked the IL-17A-mediated G-CSF release. We demonstrated the potential ability of IL-17A to induce G-CSF in renal proximal tubular cells. It is proposed that IL-17A may play an important role in neutrophil transmigration and activation via stimulation of G-CSF in tubular injury.

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Abstract 385: TRPA1 Mediates Angiotensinogen Augmentation in Renal Proximal Tubular Cells

Hypertension ◽

10.1161/hyp.60.suppl_1.a385 ◽

2012 ◽

Vol 60 (suppl_1) ◽

Author(s):

Ryousuke Satou ◽

Andrea Zsombok ◽

Andrei V Derbenev

Keyword(s):

Oxidative Stress ◽

Western Blot ◽

P38 Mapk ◽

Rt Pcr ◽

Proximal Tubular Cells ◽

Tubular Cells ◽

Proximal Tubular ◽

Renal Proximal Tubular Cells ◽

Renal Proximal Tubular ◽

Stimulation Of

Overactivity of the intrarenal renin-angiotensin system contributes to the development of hypertension and renal injury. In this process, regulation of angiotensinogen (AGT) in renal proximal tubular cells (RPTC) is a key factor. Oxidative stress stimulates AGT expression accompanied by activation of p38 MAPK in RPTC. Transient receptor potential A1 (TRPA1) is known to be a sensor activated by a variety of noxious stimuli including hydrogen peroxide. Activated TRPA1 induces calcium influx across the plasma membrane leading to activation of AGT-inducible signal transducers. However, the presence and function of TRPA1 in the kidney have not been delineated. Therefore, this study was performed to demonstrate expression of intrarenal TRPA1 and its role in AGT augmentation in RPTC. Expression of TRPA1 in mouse kidney and cultured mouse RPTC were determined by RT-PCR, in situ hybridization, western blot analysis and immunocytochemistry. The RPTC were treated with 100 μM H2O2 for 1 hr with or without 10μM HC030031, a TRPA1 specific antagonist. EGTA was used to the culture medium for depletion of extracellular calcium. Thereafter, AGT expression levels were evaluated by real-time RT-PCR, and TRPA1 expression levels and p38 MAPK activity were determined by western blot analyses. TRPA1 expression was observed in tubules of renal cortex, and the cultured PRTC expressed TRPA1 mRNA and protein. H2O2 increased AGT expression (1.54 ± 0.08, ratio to control) in RPTC. The AGT augmentation was suppressed by HC030031 (1.19 ± 0.05, ratio to control). Calcium depletion also resulted in attenuation of the AGT augmentation induced by H2O2. Although H2O2 induced phosphorylation of p38 MAPK, HC030031 did not inhibit the p38 MAPK activation. TRPA1 expression was increased by H2O2 under the experimental condition (1.90 ± 0.06, ratio to control). These results suggest that TRPA1 is expressed in RPTC, which contributes to H2O2-induced AGT augmentation via calcium-dependent but p38 MAPK-independent pathways. Furthermore, increase in TRPA1 expression by H2O2 likely facilitates the stimulation of AGT expression. Therefore, TRPA1 may play an important role in the progression of oxidative stress-associated renal injury and hypertension via the stimulation of AGT expression in RPTC.

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Integrative effects of EGF on metabolism and proliferation in renal proximal tubular cells

AJP Cell Physiology ◽

10.1152/ajpcell.1995.269.5.c1317 ◽

1995 ◽

Vol 269 (5) ◽

pp. C1317-C1325 ◽

Cited By ~ 28

Author(s):

G. Nowak ◽

R. G. Schnellmann

Keyword(s):

Oxygen Consumption ◽

Acid Synthesis ◽

Proximal Tubular Cells ◽

Tubular Cells ◽

Proximal Tubular ◽

Epidermal Growth ◽

Renal Proximal Tubular Cells ◽

Renal Proximal Tubular ◽

The Relationship ◽

Stimulation Of

This study examined the relationship between alterations in cellular metabolism and induction of proliferation in renal proximal tubular cells (RPTC) after epidermal growth factor (EGF) exposure. EGF treatment (10 ng/ml) of confluent RPTC cultures for 6 consecutive days increased monolayer DNA content 3.3-fold. EGF-stimulated proliferation of RPTC was preceded by a rapid (within 4 h) induction of glycolysis and a decrease in basal and ouabain-sensitive oxygen consumption (20 and 30%, respectively). EGF stimulated the pentose cycle by 58% and decreased gluconeogenesis by 48%. Supplementation of the culture medium with ribose-5-phosphate or ribose abolished the stimulation of glycolysis and the pentose cycle by EGF but had no effect on proliferation. These results show that EGF rapidly stimulates the pentose cycle, shifts glucose metabolism from gluconeogenesis to glycolysis, and decreases oxygen consumption before any increase in proliferation. The lack of an EGF effect on the pentose cycle and glycolysis in the presence of exogenous precursors for DNA synthesis suggests that the stimulation of these pathways before proliferation is due to increased demands for ribose for subsequent nucleic acid synthesis.

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Lack of Cathepsin D in the Renal Proximal Tubular Cells Resulted in Increased Sensitivity against Renal Ischemia/Reperfusion Injury

International Journal of Molecular Sciences ◽

10.3390/ijms20071711 ◽

2019 ◽

Vol 20 (7) ◽

pp. 1711 ◽

Cited By ~ 3

Author(s):

Chigure Suzuki ◽

Isei Tanida ◽

Masaki Ohmuraya ◽

Juan Oliva Trejo ◽

Soichiro Kakuta ◽

...

Keyword(s):

Epithelial Cells ◽

Cathepsin D ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Tubular Epithelial Cells ◽

Proximal Tubular Cells ◽

Tubular Cells ◽

Proximal Tubular ◽

Renal Proximal Tubular Cells ◽

Renal Proximal Tubular

Cathepsin D is one of the major lysosomal aspartic proteases that is essential for the normal functioning of the autophagy-lysosomal system. In the kidney, cathepsin D is enriched in renal proximal tubular epithelial cells, and its levels increase during acute kidney injury. To investigate how cathepsin D-deficiency impacts renal proximal tubular cells, we employed a conditional knockout CtsDflox/−; Spink3Cre mouse. Immunohistochemical analyses using anti-cathepsin D antibody revealed that cathepsin D was significantly decreased in tubular epithelial cells of the cortico-medullary region, mainly in renal proximal tubular cells of this mouse. Cathepsin D-deficient renal proximal tubular cells showed an increase of microtubule-associated protein light chain 3 (LC3; a marker for autophagosome/autolysosome)-signals and an accumulation of abnormal autophagic structures. Renal ischemia/reperfusion injury resulted in an increase of early kidney injury marker, Kidney injury molecule 1 (Kim-1), in the cathepsin D-deficient renal tubular epithelial cells of the CtsDflox/−; Spink3Cre mouse. Inflammation marker was also increased in the cortico-medullary region of the CtsDflox/−; Spink3Cre mouse. Our results indicated that lack of cathepsin D in the renal tubular epithelial cells led to an increase of sensitivity against ischemia/reperfusion injury.

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Costimulation with angiotensin II and interleukin 6 augments angiotensinogen expression in cultured human renal proximal tubular cells

AJP Renal Physiology ◽

10.1152/ajprenal.00047.2008 ◽

2008 ◽

Vol 295 (1) ◽

pp. F283-F289 ◽

Cited By ~ 43

Author(s):

Ryousuke Satou ◽

Romer A. Gonzalez-Villalobos ◽

Kayoko Miyata ◽

Naro Ohashi ◽

Akemi Katsurada ◽

...

Keyword(s):

Human Kidney ◽

Ang Ii ◽

Proximal Tubular Cells ◽

Tubular Cells ◽

Human Renin ◽

Protein Expressions ◽

Proximal Tubular Epithelial Cells ◽

Proximal Tubular ◽

Renal Proximal Tubular Cells ◽

Renal Proximal Tubular

Augmented intrarenal ANG II stimulates IL-6, which contributes to renal injury. The expression of intrarenal angiotensinogen (AGT) is enhanced by increased intrarenal ANG II in human renin/human AGT double transgenic mice. ANG II also augments AGT expression in hepatocytes and cardiac myocytes. However, the mechanisms underlying AGT augmentation by ANG II and the contribution of IL-6 to this system are poorly understood. This study was performed in human renal proximal tubular epithelial cells (HRPTECs) to test the hypothesis that IL-6 contributes to the upregulation of AGT expression by ANG II. Human kidney-2 (HK-2) cells, immortalized HRPTECs, were incubated with 10−7 M ANG II and/or 10 ng/ml IL-6 for up to 24 h. AGT mRNA and protein expressions were measured by real-time RT-PCR and ELISA, respectively. The activities of NF-κB and STAT3 were evaluated by Western blotting and EMSA. Stimulation with either ANG II or IL-6 did not significantly alter AGT mRNA or protein expression. In contrast, costimulation with ANG II and IL-6 significantly increased AGT mRNA and protein expressions (1.26 ± 0.10 and 1.16 ± 0.13 over control, respectively). Olmesartan, an ANG II type 1 receptor blocker, and an IL-6 receptor antibody individually inhibited this synergistic effect. NF-κB was also activated by costimulation with ANG II and IL-6. Phosphorylation and activity of STAT3 were increased by stimulation with IL-6 alone and by costimulation. The present study indicates that IL-6 plays an important role in ANG II-mediated augmentation of AGT expression in human renal proximal tubular cells.

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