Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.550
Filtrar
1.
Eur J Med Res ; 28(1): 26, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639782

RESUMO

BACKGROUND: Aldosterone relieves transcriptional repression of epithelial sodium channel (ENaC) by inhibiting Dot1a and Af9 expression and their interaction with ENaC promoter in various tissues. Expressions of ENaC and Af9 in inner ear have been identified. However, it is not known how Dot1l is regulated by aldosterone in inner ear. METHODS: Twenty-eight adult guinea pigs were randomly divided into the control group and treatment group. Aldosterone 1 mg/kg/d was injected intraperitoneally in the treatment group and saline in the control group for 7 days. Animals were killed 1 month later following auditory brainstem response examination. Histomorphology of cochlea was detected with hematoxylin-eosin staining, and Dot1l expression was examined with immunohistochemistry and Western blot. RESULTS: There was no significant difference in ABR thresholds before and after injection of aldosterone or saline in either group. Endolymphatic hydrops was found in 75% of animals in the treatment group. Dot1l was found in both groups in the stria vascularis, Reissner's membrane, spiral limbus, organ of Corti and spiral ligament. Dot1l expression in the treatment group was decreased by aldosterone. CONCLUSIONS: Dot1l in guinea pig cochlea is inhibited by aldosterone with induction of endolymphatic hydrops. Dot1l may be closely related to endolymph regulation by aldosterone and to pathogenesis of Meniere's disease.


Assuntos
Hidropisia Endolinfática , Doença de Meniere , Cobaias , Animais , Aldosterona/farmacologia , Aldosterona/metabolismo , Cóclea/metabolismo , Cóclea/patologia , Hidropisia Endolinfática/etiologia , Hidropisia Endolinfática/metabolismo , Hidropisia Endolinfática/patologia , Doença de Meniere/complicações , Doença de Meniere/metabolismo , Doença de Meniere/patologia
2.
Int J Mol Med ; 51(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36524378

RESUMO

Renal tubulointerstitial fibrosis (TIF) is a hallmark in the continuous progression of chronic kidney disease (CKD), in which excessive activation of the renin­angiotensin­-aldosterone system serves a crucial role. Currently, there are no targeted therapies for the progression of TIF. microRNA (miR)­26a may be an ideal anti­fibrosis candidate molecule; however, the effect of miR­26 on aldosterone (ALD)­induced TIF remains unclear. This study aimed to elucidate the role of miR­26a in ALD­induced TIF. In the present study, we hypothesized that delivery of miR­26a by exosomes could attenuate ALD­induced TIF. miR­26a expression was downregulated in the kidney of ALD­induced mice compared with the mice in the sham group. Exosome­encapsulated miR­26a (Exo­miR­26a) was manufactured and injected into ALD­treated mice through the tail vein. In vivo experiments showed that Exo­miR­26a alleviated the downregulated miR­26a expression in the kidney, tubular injury and ALD­induced TIF, which was determined using Masson's trichrome staining and assessment of lipocalin 2, α­smooth muscle actin, collagen I and fibronectin expression. Moreover, in vitro experiments revealed that Exo­miR­26a inhibited epithelial­mesenchymal transition and extracellular matrix deposition in mouse tubular epithelial cells. Mechanistically, overexpressing miR­26a led to decreased expression levels of connective tissue growth factor by directly binding to its 3'­UTR and inhibiting the activation of SMAD3. These findings demonstrated that the exosomal delivery of miR­26a may alleviate ALD­induced TIF, which may provide new insights into the treatment of CKD.


Assuntos
Exossomos , MicroRNAs , Insuficiência Renal Crônica , Animais , Camundongos , Regiões 3' não Traduzidas , Aldosterona/metabolismo , Aldosterona/farmacologia , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Exossomos/genética , Exossomos/metabolismo , Fibrose , Rim/patologia , MicroRNAs/metabolismo , MicroRNAs/farmacologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Transdução de Sinais , Proteína Smad3/genética , Proteína Smad3/metabolismo
3.
Mol Cell Endocrinol ; 561: 111836, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36549461

RESUMO

Primary hyperaldosteronism is a major cause of secondary hypertension and carries additional cardiovascular risks beyond that of the elevated blood pressure. Primary hyperaldosteronism is more prevalent in obese people, and weight loss reduces aldosterone levels. It needs to be determined whether obesity related factors directly contribute to the pathogenesis of primary hyperaldosteronism. Here we show that the non-esterified fatty acids (NEFA) palmitic acid, and to a lesser extent, linoleic acid significantly stimulated aldosterone production and steroid enzyme induction in adrenocortical HAC15 cells of human origin. Palmitic acid, linoleic acid, and to a much lesser extent, oleic acid induced the expression of aldosterone synthase. Induction of the Steroidogenic Acute Regulatory Protein (StAR) was modest. Increased aldosterone secretion was independent of fatty acid beta-oxidation in the mitochondria but may involve free fatty acid receptor 1 (FFAR1/GPR40) and endoplasmic reticulum (ER) stress. Palmitic acid and linoleic acid induced the expression of C/EBP Homologous Protein (CHOP), a marker of ER stress, correlating with their ability to induce aldosterone synthase gene expression. Palmitic acid, but not linoleic acid decreased mitochondrial potentials and induced uncoupling protein 2 (UCP2). Palmitic acid enhanced, while docosahexaenoic acid (DHA) suppressed aldosterone response to angiotensin II (Ang-II). Our study provides evidence that NEFAs modulate aldosterone production, and further suggests that hyperaldosteronism shares similar pathogenesis with other obesity-related disorders such as metabolic syndrome.


Assuntos
Hiperaldosteronismo , Hipertensão , Humanos , Aldosterona/farmacologia , Aldosterona/metabolismo , Ácidos Graxos/metabolismo , Citocromo P-450 CYP11B2/genética , Hiperaldosteronismo/genética , Ácido Palmítico/farmacologia
4.
Peptides ; 160: 170925, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36549423

RESUMO

The renal kallikrein-kinin system (RKKS) has been related to blood pressure control and sodium and water balance. We have previously shown that female spontaneously hypertensive rats (SHR) have high urinary kallikrein activity (UKa) and lower blood pressure (BP) than males whereas ovariectomy stimulates UKa and diminishes BP. We also showed that high K+ intake and prepuberal gonadectomy (Gx) diminish BP with a concomitant increase in UKa and plasma aldosterone levels. Since kallikrein co-localize in the same distal nephron segments of aldosterone effectors, we explored the effect of pharmacological blockage of aldosterone receptor, epithelial Na+ (ENaC) and the rectifying outer medulla K+ (ROMK) channels in different gonad contexts on the gene expression, renal tissue content and urine release of kallikrein. Klk1 gene expression was determined by real-time PCR and enzymatic activity of kallikrein by the amidolytic method. We found that the inhibition of the aldosterone receptor by spironolactone increases kallikrein renal tissue storage and decreases its urinary activity, especially in Gx rats. Moreover, ENaC blockade by benzamil increases the renal content of kallikrein without affecting synthesis or excretion, especially in females and Gx animals, while the inhibition of ROMK by glibenclamide increases the synthesis and renal content of kallikrein only in intact male animals. We concluded that RKKS regulation showed sexual dimorphism and seemed to be modulated by sex hormones throughout a process involving aldosterone and the aldosterone-sensitive ion channels..


Assuntos
Aldosterona , Hipertensão , Masculino , Ratos , Feminino , Animais , Aldosterona/metabolismo , Ratos Endogâmicos SHR , Receptores de Mineralocorticoides/metabolismo , Hipertensão/metabolismo , Calicreínas/genética , Calicreínas/metabolismo , Rim/metabolismo , Néfrons/metabolismo , Sódio/metabolismo , Canais Iônicos/metabolismo , Canais Epiteliais de Sódio/genética , Canais Epiteliais de Sódio/metabolismo
5.
PLoS One ; 17(12): e0279682, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36584094

RESUMO

The sharp line of demarcation between zona glomerulosa (ZG) and zona fasciculata (ZF) has been recently challenged suggesting that this interface is no longer a compartment boundary. We have used immunohistochemical analyses to study the steroid 11ß-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) pattern of expression and investigate the remodeling of the adrenal cortex in relation to aging. We analyzed human adrenal glands prepared from 47 kidney donors. No aldosterone-producing micronodules (APMs) were detectable in the younger donors aged between 22-39 but the functional ZG depicted by positive CYP11B2 staining demonstrated a lack of continuity. In contrast, the development of APMs was found in samples from individuals aged 40-70. Importantly, the progressive replacement of CYP11B2-expressing cells in the histological ZG by CYP11B1-expressing cells highlights the remodeling capacity of the adrenal cortex. In 70% of our samples, immunofluorescence studies revealed the presence of isolated or clusters of CYP11B2 positive cells in the ZF and zona reticularis. Our data emphasize that mineralocorticoid- and glucocorticoid-producing cells are distributed throughout the cortex and the medulla making the determination of the functional status of a cell or group of cells a unique tool in deciphering the changes occurring in adrenal gland particularly during aging. They also suggest that, in humans, steroidogenic cell phenotype defined by function is a stable feature and thus, the functional zonation might be not solely maintained by cell lineage conversion/migration.


Assuntos
Córtex Suprarrenal , Esteroide 11-beta-Hidroxilase , Humanos , Adulto Jovem , Adulto , Esteroide 11-beta-Hidroxilase/genética , Esteroide 11-beta-Hidroxilase/metabolismo , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Córtex Suprarrenal/metabolismo , Glândulas Suprarrenais/metabolismo , Aldosterona/metabolismo
6.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36499387

RESUMO

Both aldosterone and arginine vasopressin (AVP) are produced in the heart and may participate in cardiac fibrosis. However, their relationship remains unknown. This study aims to demonstrate the regulation and role of AVP in aldosterone synthesis in the heart. Rats were subjected to a sham operation or myocardial infarction (MI) by ligating the coronary artery. Cardiac function and fibrosis were assessed using echocardiography and immunohistochemical staining, respectively. In addition, the effects of AVP stimulation on cardiac microvascular endothelial cells (CMECs) were studied using ELISA, real-time PCR, and Western blotting. Compared with the rats having undergone a sham operation, the MI rats had an increased LVMI, type I collagen composition, and concentrations of aldosterone and AVP in the heart but decreased cardiac function. As the MI rats aged, the LVMI, type I collagen, aldosterone, and AVP increased, while the LVMI decreased. Furthermore, AVP time-dependently induced aldosterone secretion and CYP11B2 mRNA expression in CMECs. The p-CREB levels were significantly increased by AVP. Nevertheless, these effects were completely blocked by SR49059 or partially inhibited by KN93. This study demonstrated that AVP could induce the secretion of local cardiac aldosterone, which may involve CaMK and CREB phosphorylation and CYP11B2 upregulation through V1 receptor activation.


Assuntos
Arginina Vasopressina , Infarto do Miocárdio , Ratos , Animais , Arginina Vasopressina/farmacologia , Arginina Vasopressina/metabolismo , Colágeno Tipo I , Células Endoteliais/metabolismo , Coração , Aldosterona/metabolismo , Fibrose
7.
Int J Mol Sci ; 23(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36430298

RESUMO

In this review, we describe previous basic and clinical studies on autonomous aldosterone production. Over the past decades, mineralocorticoid receptor antagonists (MRAs) have been found to concentration-dependently inhibit steroidogenesis in different degrees. However, many studies have proven the suppressive effects of MRAs on the activities of hormone synthase. The probable factors of cytochrome P-450 reduction, both in microsomes and mitochondria, have also been considered: (1) one of the spironolactone metabolite forms had destructive function, except canrenone, (2) 7α-thio-spironolactone was an obligatory intermediate in the spironolactone-induced CYP450 decrease, and (3) the contributing steroids should have 7α-methylthio or 7α-methylsulfone groups. In previous clinical research, spironolactone-body-containing cells showed a type II pattern of enzyme activity (i.e., enhanced 3ß-hydroxysteroid dehydrogenase, glucose-6-phosphate, and NADP-isocitrate dehydrogenase activities and weaken succinate dehydrogenase activity), and the subcapsular micronodules composed of spironolactone-body-containing cells also exhibited a type II pattern and excess aldosterone secretion, indicating that the subcapsular micronodules might be the root of aldosterone-producing adenoma. Moreover, combined with the potential impeditive function to aldosterone secretion, a few cases of spontaneous remission of primary aldosteronism, with normal ranges of blood pressure, plasma potassium, plasma renin activity, and aldosterone renin ratio, have been reported after long-term treatment with MRAs.


Assuntos
Hiperaldosteronismo , Antagonistas de Receptores de Mineralocorticoides , Humanos , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Aldosterona/metabolismo , Espironolactona/farmacologia , Espironolactona/uso terapêutico , Mineralocorticoides , Hiperaldosteronismo/tratamento farmacológico , Hiperaldosteronismo/metabolismo , Renina , Remissão Espontânea
8.
Endocrinology ; 164(1)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36320101

RESUMO

BACKGROUND: Mammalian target of rapamycin (mTOR) inhibitors suppress adrenal cortical carcinoma cell proliferation and cortisol production; the relationship between mTOR and aldosterone production has not been examined. METHODS: HAC15 cells were incubated with an mTOR activator and several inhibitors including AZD8055 (AZD) in the presence and absence of angiotensin II (AngII). The expression of rapamycin-sensitive adapter protein of mTOR (Raptor) and rapamycin-insensitive companion of mTOR (Rictor), adaptor proteins of mTOR complex 1 and 2, respectively, were studied in the HAC15 cells and deleted by CRISPR/gRNA. RESULTS: The mTOR inhibitors decreased aldosterone induced by AngII. Inhibition of mTOR by AZD significantly suppressed AngII-induced aldosterone and cortisol formation in a dose-dependent manner, whereas the mTOR activator MHY had no effect. AZD did not alter forskolin-induced aldosterone production showing that it is specific to the AngII signaling pathway. AngII-mediated ERK and mTOR activation were suppressed by AZD, along with a concomitant dose-dependent reduction of AngII-induced steroidogenic enzymes including steroidogenic acute regulatory protein, 3ß-hydroxysteroid dehydrogenase-type 2, CYP17A1, and aldosterone synthase protein. Furthermore, mTOR components ribosomal protein S6 kinase (P70S6K) and protein kinase B phosphorylation levels were decreased by AZD. As mTOR exerts its main effects by forming complexes with adaptor proteins Raptor and Rictor, the roles of these individual complexes were studied. We found an increase in the phosphorylation of Raptor and Rictor by AngII and that their CRISPR/gRNA-mediated knockdown significantly attenuated AngII-induced aldosterone and cortisol production. CONCLUSION: mTOR signaling has a critical role in transducing the AngII signal initiating aldosterone and cortisol synthesis in HAC15 cells and that inhibition of mTOR could be a therapeutic option for conditions associated with excessive renin-angiotensin system-mediated steroid synthesis.


Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Humanos , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Aldosterona/metabolismo , Hidrocortisona/metabolismo , Sirolimo/farmacologia , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Serina-Treonina Quinases TOR
9.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36361592

RESUMO

Primary aldosteronism (PA) is considered the most common form of secondary hypertension, which is associated with excessive aldosterone secretion in the adrenal cortex. The cause of excessive aldosterone secretion is the induction of aldosterone synthase gene (CYP11B2) expression by depolarization of adrenocortical cells. In this study, we found that YM750, an Acyl-coenzyme A: cholesterol acyltransferase (ACAT) inhibitor, acts on adrenocortical cells to suppress CYP11B2 gene expression and aldosterone secretion. YM750 inhibited the induction of CYP11B2 gene expression by KCl stimulation, but not by angiotensin II and forskolin stimulation. Interestingly, YM750 did not inhibit KCl-stimulated depolarization via an increase in intracellular calcium ion concentration. Moreover, ACAT1 expression was relatively abundant in the zona glomerulosa (ZG) including these CYP11B2-positive cells. Thus, YM750 suppresses CYP11B2 gene expression by suppressing intracellular signaling activated by depolarization. In addition, ACAT1 was suggested to play an important role in steroidogenesis in the ZG. YM750 suppresses CYP11B2 gene expression and aldosterone secretion in the adrenal cortex, suggesting that it may be a potential therapeutic agent for PA.


Assuntos
Córtex Suprarrenal , Citocromo P-450 CYP11B2 , Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/metabolismo , Aldosterona/metabolismo , Aciltransferases/metabolismo , Zona Glomerulosa/metabolismo , Córtex Suprarrenal/metabolismo
10.
Int J Mol Sci ; 23(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36293446

RESUMO

The mineralocorticoid receptor (MR) is a member of the steroid receptor family and acts as a ligand-dependent transcription factor. In addition to its classical effects on water and electrolyte balance, its involvement in the pathogenesis of cardiovascular and renal diseases has been the subject of research for several years. The molecular basis of the latter has not been fully elucidated, but an isolated increase in the concentration of the MR ligand aldosterone or MR expression does not suffice to explain long-term pathologic actions of the receptor. Several studies suggest that MR activity and signal transduction are modulated by the surrounding microenvironment, which therefore plays an important role in MR pathophysiological effects. Local changes in micromilieu, including hypoxia, ischemia/reperfusion, inflammation, radical stress, and aberrant salt or glucose concentrations affect MR activation and therefore may influence the probability of unphysiological MR actions. The surrounding micromilieu may modulate genomic MR activity either by causing changes in MR expression or MR activity; for example, by inducing posttranslational modifications of the MR or novel interaction with coregulators, DNA-binding sites, or non-classical pathways. This should be considered when developing treatment options and strategies for prevention of MR-associated diseases.


Assuntos
Aldosterona , Receptores de Mineralocorticoides , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Aldosterona/metabolismo , Ligantes , DNA , Fatores de Transcrição , Água , Glucose
11.
Kidney Int ; 102(6): 1247-1258, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36228680

RESUMO

The mammalian distal nephron is a target of highly effective antihypertensive drugs. Genetic variants that alter its transport activity are also inherited causes of high or low blood pressure, clearly establishing its central role in human blood pressure regulation. Much has been learned during the past 25 years about salt transport along this nephron segment, spurred by the cloning of major transport proteins and the discovery of disease-causing genetic variants. Recognition is increasing that substantial cellular and segmental heterogeneity is present along this segment, with electroneutral sodium transport dominating more proximal segments and electrogenic sodium transport dominating more distal segments. Coupled with recent insights into factors that modulate transport along these segments, we now understand one important mechanism by which dietary potassium intake influences sodium excretion and blood pressure. This finding has solved the aldosterone paradox, by demonstrating how aldosterone can be both kaliuretic, when plasma potassium is elevated, and anti-natriuretic, when extracellular fluid volume is low. However, what also has become clear is that aldosterone itself only stimulates a portion of the mineralocorticoid receptors along this segment, with the others being activated by glucocorticoid hormones instead. These recent insights provide an increasingly clear picture of how this short nephron segment contributes to blood pressure homeostasis and have important implications for hypertension prevention and treatment.


Assuntos
Aldosterona , Hipertensão , Animais , Humanos , Pressão Sanguínea , Aldosterona/metabolismo , Néfrons/metabolismo , Sódio/metabolismo , Mamíferos/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-36185701

RESUMO

Introduction: Cardiovascular disease constitutes the leading cause of mortality in patients with chronic kidney disease (CKD), which is termed cardiorenal syndrome type 4 (CRS-4). Here, we report the development of pathological cardiac remodeling and fibrosis in unilateral urinary obstruction (UUO) rats. Methods: Hematoxylin and eosin (H&E) staining was performed to observe the pathology of myocardial tissue. The degree of myocardial tissue fibrosis was observed by Masson and Sirius red staining. Immunohistochemical staining was applied to detect the expression of CD34 and CD105 in myocardial tissue, and immunofluorescent staining was performed to examine the expression of CD34, collagen I/collagen III, and alpha smooth muscle actin (α-SMA). The expression of the signal pathway-related proteins vascular endothelial growth factor A (VEGFA), vascular endothelial growth factor receptor 2 (VEGFR2), nuclear factor κB (NF-κB), and interleukin (IL)-1ß was tested by western blotting. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA levels of serum and glucocorticoid-inducible kinase (SGK)-1, NF-κB, and interleukin-1ß (IL-1ß). Results: The results showed the development of pathological cardiac remodeling and cardiac dysfunction in UUO rats. Moreover, there was more angiogenesis and endothelial-mesenchymal transition (End-MT) in the UUO group, and these effects were inhibited by eplerenone. Conclusions: The results indicated that this cardiac fibrosis was associated with angiogenesis and that End-MT was related to aldosterone and mineralocorticoid receptor (MR) activation. Moreover, in association with the MR/IL-1ß/VEGFA signaling pathway, early treatment with the MR antagonist eplerenone in rats with UUO-induced CKD may significantly attenuate MR activation and cardiac fibrosis.


Assuntos
Insuficiência Renal Crônica , Obstrução Ureteral , Actinas/metabolismo , Aldosterona/metabolismo , Animais , Colágeno/metabolismo , Amarelo de Eosina-(YS)/metabolismo , Amarelo de Eosina-(YS)/farmacologia , Eplerenona/farmacologia , Fibrose , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Hematoxilina/metabolismo , Hematoxilina/farmacologia , Interleucina-1beta , Rim/patologia , NF-kappa B/metabolismo , NF-kappa B/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Insuficiência Renal Crônica/complicações , Obstrução Ureteral/complicações , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/farmacologia , Remodelação Ventricular
13.
Sci Rep ; 12(1): 15955, 2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153401

RESUMO

Proteolytic activation of the renal epithelial sodium channel (ENaC) is increased by aldosterone. The aldosterone-sensitive protease remains unidentified. In humans, elevated circulating aldosterone is associated with increased urinary extracellular vesicle (uEVs) excretion of mannan-binding lectin associated serine protease-2 (MASP-2). We hypothesized that MASP-2 is a physiologically relevant ENaC-activating protease. It was confirmed that MASP2 mRNA is abundantly present in liver but not in human and mouse kidneys. Aldosterone-stimulation of murine cortical colleting duct (mCCD) cells did not induce MASP-2 mRNA. In human kidney collecting duct, MASP-2 protein was detected in AQP2-negative/ATP6VB1-positive intercalated cells suggestive of MASP2 protein uptake. Plasma concentration of full-length MASP-2 and the short splice variant MAp19 were not changed in a cross-over intervention study in healthy humans with low (70 mmol/day) versus high (250 mmol/day) Na+ intake despite changes in aldosterone. The ratio of MAp19/MASP-2 in plasma was significantly increased with a high Na+ diet and the ratio correlated with changes in aldosterone and fractional Na+ excretion. MASP-2 was not detected in crude urine or in uEVs. MASP2 activated an amiloride-sensitive current when co-expressed with ENaC in Xenopus oocytes, but not when added to the bath solution. In monolayers of collecting duct M1 cells, MASP2 expression did not increase amiloride-sensitive current and in HEK293 cells, MASP-2 did not affect γENaC cleavage. MASP-2 is neither expressed nor co-localized and co-regulated with ENaC in the human kidney or in urine after low Na+ intake. MASP-2 does not mediate physiological ENaC cleavage in low salt/high aldosterone settings.


Assuntos
Túbulos Renais Coletores , Serina Proteases Associadas a Proteína de Ligação a Manose , Aldosterona/metabolismo , Amilorida/farmacologia , Animais , Aquaporina 2/metabolismo , Canais Epiteliais de Sódio/metabolismo , Células HEK293 , Humanos , Rim/metabolismo , Túbulos Renais Coletores/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Camundongos , RNA Mensageiro/metabolismo , Sódio/metabolismo
14.
Kidney360 ; 3(5): 910-921, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-36128481

RESUMO

Background: Sodium chloride (NaCl) loading and volume expansion suppress the renin-angiotensin-aldosterone system to reduce renal tubular reabsorption of NaCl and water, but effects on the sodium-chloride cotransporter (NCC) and relevant renal transmembrane proteins that are responsible for this modulation in humans are less well investigated. Methods: We used urinary extracellular vesicles (uEVs) as an indirect readout to assess renal transmembrane proteins involved in NaCl and water homeostasis in 44 patients with hypertension who had repeatedly raised aldosterone/renin ratios undergoing infusion of 2 L of 0.9% saline over 4 hours. Results: When measured by mass spectrometry in 13 patients, significant decreases were observed in NCC (median fold change [FC]=0.70); pendrin (FC=0.84); AQP2 (FC=0.62); and uEV markers, including ALIX (FC=0.65) and TSG101 (FC=0.66). Immunoblotting reproduced the reduction in NCC (FC=0.54), AQP2 (FC=0.42), ALIX (FC=0.52), and TSG101 (FC=0.55) in the remaining 31 patients, and demonstrated a significant decrease in phosphorylated NCC (pNCC; FC=0.49). However, after correction for ALIX, the reductions in NCC (FC=0.90) and pNCC (FC=1.00) were no longer apparent, whereas the significant decrease in AQP2 persisted (FC=0.62). Conclusion: We conclude that (1) decreases in NCC and pNCC, induced by acute NaCl loading and volume expansion, may be due to diluted post-test urines; (2) the lack of change of NCC and pNCC when corrected for ALIX, despite a fall in plasma aldosterone, may be due to the lack of change in plasma K+; and (3) the decrease in AQP2 may be due to a decrease in vasopressin in response to volume expansion.


Assuntos
Vesículas Extracelulares , Simportadores de Cloreto de Sódio , Aldosterona/metabolismo , Aquaporina 2/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Fosforilação , Renina/metabolismo , Solução Salina/metabolismo , Cloreto de Sódio/metabolismo , Água/metabolismo
15.
PLoS One ; 17(9): e0273313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36129874

RESUMO

HIV-associated nephropathy (HIVAN) impairs functions of both glomeruli and tubules. Attention has been previously focused on the HIVAN glomerulopathy. Tubular injury has drawn increased attention because sodium wasting is common in hospitalized HIV/AIDS patients. We used viral protein R (Vpr)-transgenic mice to investigate the mechanisms whereby Vpr contributes to urinary sodium wasting. In phosphoenolpyruvate carboxykinase promoter-driven Vpr-transgenic mice, in situ hybridization showed that Vpr mRNA was expressed in all nephron segments, including the distal convoluted tubule. Vpr-transgenic mice, compared with wild-type littermates, markedly increased urinary sodium excretion, despite similar plasma renin activity and aldosterone levels. Kidneys from Vpr-transgenic mice also markedly reduced protein abundance of the Na+-Cl- cotransporter (NCC), while mineralocorticoid receptor (MR) protein expression level was unchanged. In African green monkey kidney cells, Vpr abrogated the aldosterone-mediated stimulation of MR transcriptional activity. Gene expression of Slc12a3 (NCC) in Vpr-transgenic mice was significantly lower compared with wild-type mice, assessed by both qRT-PCR and RNAScope in situ hybridization analysis. Chromatin immunoprecipitation assays identified multiple MR response elements (MRE), located from 5 kb upstream of the transcription start site and extending to the third exon of the SLC12A3 gene. Mutation of MRE and SP1 sites in the SLC12A3 promoter region abrogated the transcriptional responses to aldosterone and Vpr, indicating that functional MRE and SP1 are required for the SLC12A3 gene suppression in response to Vpr. Thus, Vpr attenuates MR transcriptional activity and inhibits Slc12a3 transcription in the distal convoluted tubule and contributes to salt wasting in Vpr-transgenic mice.


Assuntos
Produtos do Gene vpr , HIV-1 , Aldosterona/metabolismo , Aldosterona/farmacologia , Animais , Chlorocebus aethiops , Produtos do Gene vpr/metabolismo , HIV-1/genética , Túbulos Renais Distais/metabolismo , Camundongos , Camundongos Transgênicos , Fosfoenolpiruvato , RNA Mensageiro/metabolismo , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Renina/metabolismo , Sódio/metabolismo , Cloreto de Sódio/metabolismo , Simportadores de Cloreto de Sódio/metabolismo , Membro 3 da Família 12 de Carreador de Soluto/genética , Membro 3 da Família 12 de Carreador de Soluto/metabolismo , Tiazidas
16.
Pharmacol Res Perspect ; 10(5): e00995, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36065843

RESUMO

Aldosterone exerts some of its effects not by binding to mineralocorticoid receptors, but rather by acting via G protein-coupled estrogen receptors (GPER). To determine if aldosterone binds directly to GPER, we studied the ability of aldosterone to compete for the binding of [3 H] 2-methoxyestradiol ([3 H] 2-ME), a high potency GPER-selective agonist. We used GPER gene transfer to engineer Sf9-cultured insect cells to express GPER. We chose insect cells to avoid interactions with any intrinsic mammalian receptors for aldosterone. [3 H] 2-ME binding was saturable and reversible to a high-affinity population of receptors with Kd  = 3.7 nM and Bmax  = 2.2 pmol/mg. Consistent with agonist binding to G Protein-coupled receptors, [3 H] 2-ME high-affinity state binding was reduced in the presence of the hydrolysis-resistant GTP analog, GppNHp. [3 H] 2-ME binding was competed for by the GPER agonist G1, the GPER antagonist G15, estradiol (E2), as well as aldosterone (Aldo). The order of potency for competing for [3 H] 2-ME binding, namely 2ME > Aldo > E2 ≥ G1, paralleled the orders of potency for inhibition of cell proliferation and inhibition of ERK phosphorylation by ligands acting at GPER. These data confirm the ability of aldosterone to interact with the GPER, consistent with the interpretation that aldosterone likely mediates its GPER-dependent effects by direct binding to the GPER. SIGNIFICANCE STATEMENT: Despite the growing evidence for aldosterone's actions via G protein-coupled estrogen receptors (GPER), there remains significant skepticism that aldosterone can directly interact with GPER. The current studies are the first to demonstrate directly that aldosterone indeed is capable of binding to the GPER and thus likely mediates its GPER-dependent effects by direct binding to the receptor.


Assuntos
Aldosterona , Receptores de Estrogênio , Aldosterona/metabolismo , Animais , Estrogênios , Proteínas de Ligação ao GTP/metabolismo , Mamíferos/metabolismo , Mercaptoetanol , Receptores Acoplados a Proteínas G/metabolismo
17.
Cells ; 11(17)2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36078114

RESUMO

The aim of this study was to evaluate the effect of acute aldosterone (ALDO) administration on the vascular permeability of skin. ALDO was injected intradermally into rats, and vascular permeability was measured. Eplerenone (EPL), a selective mineralocorticoid receptor (MR) antagonist, was used. Skin biopsies were carried out for immunohistochemical (IHC) staining, and polymerase chain reactions were performed to analyze the expression of MR, 11ß-hydroxysteroid dehydrogenase type 2, von Willebrand factor (vWF), vascular endothelial growth factor (VEGF), and zonula occludens 1. Our study showed the presence of MR in the rat skin vasculature for the first time. It was found that ALDO injection resulted in a more than 30% increase in vascular permeability and enhanced the endothelial exocytosis of vWF. The effect of ALDO diminished after EPL administration. An accumulation of vWF and a reduction in VEGF IHC staining were observed following chronic EPL administration. No effect of ALDO or EPL on the mRNA expression of the studied genes or skin structure was observed. The results suggest that ALDO increases vascular permeability in the skin via an MR-dependent mechanism. This effect of ALDO on skin microcirculation may have important therapeutic implications for diseases characterized by increased levels of ALDO and coexisting skin microangiopathy.


Assuntos
Aldosterona , Permeabilidade Capilar , Aldosterona/metabolismo , Aldosterona/farmacocinética , Aldosterona/farmacologia , Animais , Permeabilidade Capilar/efeitos dos fármacos , Eplerenona , Antagonistas de Receptores de Mineralocorticoides , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/metabolismo
18.
Front Endocrinol (Lausanne) ; 13: 917356, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937793

RESUMO

Increasing evidence suggests that aldosterone (Aldo) plays an essential role in vascular calcification which is a serious threat to cardiovascular disease (CVD) developed from chronic kidney disease (CKD). However, the exact pathogenesis of vascular calcification is still unclear. First, we established CKD-associated vascular calcification mice model and knockout mice model to investigate the causal relationship between allograft inflammatory factor 1 (AIF-1) and vascular calcification. Then, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) co-culture experiments were performed to further explore the mechanisms of calcification. The results of the Aldo intervention mice model and transgenic mice model showed that Aldo could cause calcification by increasing the AIF-1 level. The results of in vitro co-culture model of ECs and VSMCs showed that AIF-1 silence in ECs may alleviate Aldo-induced calcification of VSMCs. In conclusion, our study indicated that Aldo may induce vascular calcification related to chronic renal failure via the AIF-1 pathway which may provide a potential therapeutic target.


Assuntos
Insuficiência Renal Crônica , Calcificação Vascular , Aldosterona/metabolismo , Animais , Técnicas de Cocultura , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/metabolismo , Calcificação Vascular/induzido quimicamente
19.
Front Endocrinol (Lausanne) ; 13: 934326, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36004349

RESUMO

Primary aldosteronism is the most common surgically curable form of hypertension. The sporadic forms of the disorder are usually caused by aldosterone overproduction from a unilateral adrenocortical aldosterone-producing adenoma or from bilateral adrenocortical hyperplasia. The main knowledge-advances in disease pathophysiology focus on pathogenic germline and somatic variants that drive the excess aldosterone production. Less clear are the molecular and cellular mechanisms that lead to an increased mass of the adrenal cortex. However, the combined application of transcriptomics, metabolomics, and epigenetics has achieved substantial insight into these processes and uncovered the evolving complexity of disrupted cell growth mechanisms in primary aldosteronism. In this review, we summarize and discuss recent progress in our understanding of mechanisms of cell death, and proliferation in the pathophysiology of primary aldosteronism.


Assuntos
Adenoma Adrenocortical , Hiperaldosteronismo , Adenoma Adrenocortical/metabolismo , Aldosterona/metabolismo , Morte Celular , Proliferação de Células , Humanos , Hiperaldosteronismo/genética , Hiperaldosteronismo/metabolismo , Hiperplasia/complicações
20.
Ecotoxicol Environ Saf ; 243: 113982, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35987080

RESUMO

Fluorene-9-bisphenol (BHPF), which has been used as a substitute for bisphenol A (BPA) in consumer goods and industrial products, can be detected in environmental media and human urine. BHPF has been reported to have endocrine-disrupting effects, whereas deleterious effects on steroidogenesis in H295R cells and underlying mechanisms are still unclear. Here, we investigated effects of BHPF on steroidogenesis using human adrenocortical carcinoma cells (H295R). Cytotoxicity was initially assessed and half-maximal inhibitory concentration (IC50) was determined based on proliferation of cells. Responses of four steroid hormones, aldosterone, cortisol, testosterone and 17ß-estradiol (E2), and ten critical genes, StAR, HMGR, CYP11A1, CYP11B1, CYP11B1, HSD3B2, CYP21, CYP17, 17ß-HSD, and CYP19, involved in steroidogenesis after exposure to non-cytotoxic concentrations of BHPF were determined in the presence or absence of 100 µM dbcAMP. Adenylate cyclase (AC) activity, intracellular concentrations of cAMP, PKA activity and amounts of steroidogenic factor-1 (SF-1) gene and expressions of proteins were determined to elucidate underlying mechanisms of effects on steroidogenesis. BHPF was cytotoxic to H295R cells in a dose- and time-dependent manner. Effects on production of hormones results demonstrated that exposure to greater concentrations of BHPF inhibited productions of aldosterone, cortisol, testosterone and E2 by down-regulation of steroidogenic genes. Inhibition of AC activity, intercellular cAMP content and PKA activity after exposure to BHPF implied that the AC/cAMP/PKA signaling pathway was involved in BHPF-induced suppression of steroidogenesis in H295R cells. Additionally, BHPF inhibited steroidogenesis and expressions of steroidogenic genes via decreasing expression of SF-1 protein, both in basal and dbcAMP-induced treatment. These results contributed to understanding molecular mechanisms of BHPF-induced effects on steroidogenesis and advancing the comprehensive risk assessment of BPs.


Assuntos
Aldosterona , Hidrocortisona , Aldosterona/metabolismo , Compostos Benzidrílicos , Bucladesina , Linhagem Celular Tumoral , Fluorenos , Humanos , Hidrocortisona/metabolismo , Fenóis , Transdução de Sinais , Esteroide 11-beta-Hidroxilase/metabolismo , Testosterona/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...