scholarly journals Modulation of steroidogenic enzymes by orphan nuclear transcriptional regulation may control diverse production of cortisol and androgens in the human adrenal

2004 ◽  
Vol 181 (2) ◽  
pp. 355-365 ◽  
Author(s):  
SN Kelly ◽  
TJ McKenna ◽  
LS Young

The capacity of the adrenal to produce cortisol is controlled in part by 21-hydroxylase (CYP21) and the production of androgens by 17-hydroxylase/17-20-lyase (CYP17), in response to secretagogues including ACTH, angiotensin-II (A-II) and insulin. In this study we examined the capacity of human adrenocortical cells to produce cortisol and androgens in response to these secretagogues and their ability to regulate the expression of CYP21 and CYP17. In H-295 cells, forskolin and A-II were found to stimulate production of cortisol relative to androstenedione and a similar pattern of steroid production was noted in primary human adrenocortical cells. Both mRNA and protein expression of CYP21 was upregulated with forskolin and A-II alone and in combination, as detected by Northern and Western blotting. Whereas expression of CYP17 mRNA and protein was up regulated in the presence of forskolin and forskolin in combination with insulin. The ability of steroidogenic factor-1 (SF-1) and nur77 to regulate transcription of these enzymes was examined. Forskolin, A-II and insulin increased the protein expression of SF-1. Increased binding of SF-1 to its response element in the presence of forskolin, A-II and insulin was observed. Nur77 was expressed primarily in the zona glomerulosa and fasciculata. Increased protein expression of nur77 and the greatest binding of nur77 to its response element was seen when cells were stimulated with A-II in combination with forskolin. These data indicate that nur77 may preferentially regulate steroid enzyme genes relevant to cortisol production and thereby regulate differential cortisol and adrenal androgen production.

1983 ◽  
Vol 104 (1) ◽  
pp. 103-109 ◽  
Author(s):  
Wolfgang Belmega ◽  
Wolfgang Oelkers ◽  
Lutz Belkien ◽  
Monika Shirpai ◽  
Ulrich Fiedler ◽  
...  

Abstract. Isolated adrenocortical cells from 6 patients with a 'normal' zona fasciculata, 4 patients with a 'normal' zona glomerulosa, and tumour cells from 1 adrenocortical adenoma and 1 carcinoma were incubated with and without increasing concentrations of ACTH 1–24 (10−13 m to 10−9 m) or Asp1-Ile5-angiotensin II (10−11 m to 10−7 m). In 4/5 'normal' cases, cortisol was clearly stimulated by 10−13 m ACTH. The maximum of the dose-response curve (5-fold stimulation) was reached at 10−10 m ACTH. Angiotensin II (All) started to stimulate 'normal' cells at 10−11 m with a maximum (2-fold stimulation) at 10−9 m. Aldosterone production by 'normal' cells was less markedly stimulated by ACTH and All, although the threshold doses for both peptides were similar to those of the cortisol response curves. The cells of the adrenocortical adenoma from a patient with Cushing's syndrome produced large amounts of cortisol and small amounts of aldosterone, both steroids being clearly stimulated by ACTH and AII. The adrenocortical carcinoma cells produced small amounts of cortisol and no aldosterone. Cortisol production responded to ACTH, but not to AII. The results suggest that an activated renin-angiotensin system may stimulate the zona fasciculata, since 10−11 m All (= 10 pg AII/ml) is a normal plasma All concentration on an unrestricted diet. Clinical evidence supporting this thesis is reviewed. However, cortisol production itself will rarely be increased by All in vivo, since a downregulation of ACTH would occur.


2010 ◽  
Vol 298 (2) ◽  
pp. F381-F390 ◽  
Author(s):  
Ilaria Miceli ◽  
Davina Burt ◽  
Elena Tarabra ◽  
Giovanni Camussi ◽  
Paolo Cavallo Perin ◽  
...  

Increased glomerular permeability to proteins is a characteristic feature of diabetic nephropathy (DN). The slit diaphragm is the major restriction site to protein filtration, and the loss of nephrin, a key component of the slit diaphragm, has been demonstrated in both human and experimental DN. Both systemic and glomerular hypertension are believed to be important in the pathogenesis of DN. Human immortalized podocytes were subjected to repeated stretch-relaxation cycles by mechanical deformation with the use of a stress unit (10% elongation, 60 cycles/min) in the presence or absence of candesartan (1 μM), PD-123319 (1 μM), and rosiglitazone (0.1 μM). Nephrin mRNA and protein expression were assessed using quantitative real-time PCR, immunoblotting, and immunofluorescence, and the protein expression of AT1 receptor and angiotensin II secretion were evaluated. Exposure to stretch induced a significant ∼50% decrease in both nephrin mRNA and protein expression. This effect was mediated by an angiotensin II-AT1 mechanism. Indeed, podocyte stretching induced both angiotensin II secretion and AT1 receptor overexpression, podocyte exposure to angiotensin II reduced nephrin protein expression, and both the AT-1 receptor antagonist candesartan and a specific anti-angiotensin II antibody completely abolished stretch-induced nephrin downregulation. Similar to candesartan, the peroxisome proliferator-activated receptor (PPAR)-γ agonist, rosiglitazone, also inhibited stretch-induced nephrin downregulation, suggesting interference with stretch-induced activation of the angiotensin II-AT1 receptor system. Accordingly, rosiglitazone did not alter stretch-induced angiotensin II secretion, but it prevented AT1 upregulation in response to stretch. These results suggest a role for hemodynamic stress in loss of nephrin expression and allude to a role of PPAR-γ agonists in the prevention of this loss.


2015 ◽  
Vol 408 ◽  
pp. 38-44 ◽  
Author(s):  
Melina Dattilo ◽  
Isabel Neuman ◽  
Mariana Muñoz ◽  
Paula Maloberti ◽  
Fabiana Cornejo Maciel

2020 ◽  
Vol 48 (6) ◽  
pp. 030006052092635
Author(s):  
Guo-wei Wei ◽  
Ke-yue Li ◽  
Ke-li Tang ◽  
Cheng-Xian Shi

Objective To investigate the effects of tanshinone IIA on the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway in angiotensin II-treated hepatic stellate cells (HSCs). Methods HSCs were cultured and treated with angiotensin II (10 μM) or angiotensin II (10 μM) plus tanshinone IIA (3, 10, or 30 μM). Cells were incubated for 48 hours and proliferation was determined with the Cell Counting Kit-8. The relative mRNA expression of TGF-β1, Smad4, and Smad7 was measured by quantitative real-time PCR, and the relative protein expression levels were investigated by western blotting. Results After angiotensin II treatment, cell proliferation was significantly accelerated. Furthermore, both the mRNA and protein expression of TGF-β1 and Smad4 was significantly up-regulated, while the mRNA and protein expression of Smad7 was significantly down-regulated compared with the control cells. Tanshinone IIA inhibited the observed effects of angiotensin II in a concentration-dependent manner, with significant inhibition exerted by tanshinone IIA at 10 and 30 μM. Conclusions Angiotensin II promotes the proliferation of HSCs, possibly by regulating the expression of components along the TGF-β1/Smads signaling pathway. Tanshinone IIA inhibits the angiotensin II-induced activation of this pathway, and may, therefore, have preventive and therapeutic effects in liver fibrosis.


Endocrinology ◽  
2009 ◽  
Vol 150 (8) ◽  
pp. 3483-3492 ◽  
Author(s):  
Adam S. Sirek ◽  
Ling Liu ◽  
Mark Naples ◽  
Khosrow Adeli ◽  
Dominic S. Ng ◽  
...  

The carbohydrate response element binding protein (ChREBP) has been recognized as a key controller of hepatic lipogenesis. Whereas the function of ChREBP has been extensively investigated, mechanisms underlying its transcription remain largely unknown, although ChREBP production is elevated in a hyperinsulinemic mouse model. We located a conserved Pit-1, Oct-1/Oct-2, and Unc-86 (POU) protein binding site (ATGCTAAT) within the proximal promoter region of human ChREBP. This site interacts with the POU homeodomain protein octamer transcription factor-1 (Oct-1), as detected by gel shift and chromatin immunoprecipitation assays. Oct-1 cotransfection in the human HepG2 cell line repressed ChREBP promoter activity approximately 50–75% (P < 0.01 to P < 0.001), and this repression was dependent on the existence of the POU binding site. Furthermore, overexpression of Oct-1 repressed endogenous ChREBP mRNA and protein expression, whereas knockdown of Oct-1 expression, using a lentivirus-based small hairpin RNA approach, led to increased ChREBP mRNA and protein expression. In contrast, HepG2 cells treated with 10 or 100 nm insulin for 4 or 8 h resulted in an approximately 2-fold increase of ChREBP promoter activity (P < 0.05 to P < 0.01). Insulin (10 nm) also stimulated endogenous ChREBP expression in HepG2 and primary hamster hepatocytes. More importantly, we found that the stimulatory effect of insulin on ChREBP promoter activity was dependent on the presence of the POU binding site, and insulin treatment reduced Oct-1 expression levels. Our observations therefore identify Oct-1 as a transcriptional repressor of ChREBP and suggest that insulin stimulates ChREBP expression via attenuating the repressive effect of Oct-1.


2007 ◽  
Vol 214 (3) ◽  
pp. 750-756 ◽  
Author(s):  
Wenli Wang ◽  
Carolyn A. Haller ◽  
Jing Wen ◽  
Peiyi Wang ◽  
Elliot L. Chaikof

2003 ◽  
pp. 139-145 ◽  
Author(s):  
LS Young ◽  
G Murphy ◽  
SN Kelly ◽  
TP Smith ◽  
SK Cunningham ◽  
...  

OBJECTIVES: The adrenal cortex produces aldosterone, cortisol and androgens in response to ACTH and angiotensin II. To define the differential response of morphologically distinct cells of the adrenal cortex, we examined the phenotypical and functional characteristics of human adrenocortical cells. RESULTS: Tumour growth factor-beta receptor-1 (TGFbeta-R1) and CYP-11 were found to be expressed predominantly in the zona fasciculata, whereas human leukocyte antigen (HLA-DR) and CYP-17 were localised to the zona reticularis. The angiotensin II receptor, AT-1, was found to be predominantly expressed in the zona glomerulosa. Adrenocortical cells, separated by density, yielded two distinct fractions which displayed differential growth patterns. Lipid-rich cells of fraction I expressed TGFbeta-R1 and produced significantly more cortisol relative to androstenedione than unseparated or fraction II cells, whereas lipid-poor cells of fraction II expressed HLA-DR and produced more androstenedione relative to cortisol in the presence of ACTH. Aldosterone production by fraction II was significantly greater than fraction I or unseparated cells. TGFbeta-R1-positive fasciculata-type cells separated into fraction I and HLA-DR-positive cells consistent with reticularis cells separated into fraction II. Aldosterone-producing cells indicative of glomerulosa cells separated into fraction II. CONCLUSIONS: Our findings are consistent with the concept that all adrenocortical cells are capable of producing a range of steroids, but the relative production of cortisol, androgen and aldosterone differs.


2017 ◽  
Vol 312 (2) ◽  
pp. F245-F253 ◽  
Author(s):  
Kexin Peng ◽  
Xiaohan Lu ◽  
Fei Wang ◽  
Adam Nau ◽  
Ren Chen ◽  
...  

The (pro)renin receptor (PRR) is abundantly expressed in the collecting duct (CD) and the expression is further induced by angiotensin II (ANG II). The present study was conducted to investigate the role of CD PRR during ANG II-induced hypertension and to further explore the underlying mechanism. Radiotelemetry demonstrated that a 1-wk ANG II infusion gradually and significantly induced hypertensive response in floxed mice and this response was significantly attenuated in mice lacking PRR in the CD (termed CD PRR KO). ANG II infusion in floxed mice increased urinary renin activity and selectively induced renal medullary α-epithelial sodium channel (α-ENaC) mRNA and protein expression, all of which were blunted in the null mice. In cultured mpkCCD cells grown in Transwells, transepithelial Na+ transport as measured by using a volt-ohmmeter was transiently stimulated by acute ANG II treatment, which was abolished by a PRR antagonist, PRO20. In a chronic setting, ANG II treatment induced α-ENaC mRNA expression in mpkCCD cells, which was similarly blocked by PRO20. Chronic intramedullary infusion of an ENaC inhibitor amiloride in rats significantly attenuated ANG II-induced hypertension. Overall, the present study suggests that CD PRR contributes to ANG II-induced hypertension at least partially via activation of renal medullary ENaC.


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