Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Type of study
Publication year range
1.
Biochem Pharmacol ; 216: 115763, 2023 10.
Article in English | MEDLINE | ID: mdl-37625554

ABSTRACT

Anti-hormone therapies are not efficacious for reducing the incidence of triple negative breast cancer (TNBC), which lacks both estrogen and progesterone receptors. While the etiology of this aggressive breast cancer subtype is unclear, visceral obesity is a strong risk factor for both pre- and post-menopausal cases. The mechanism by which excessive deposition of visceral adipose tissue (VAT) promotes the malignant transformation of hormone receptor-negative mammary epithelial cells is currently unknown. We developed a novel in vitro system of malignant transformation in which non-tumorigenic human breast epithelial cells (MCF-10A) grow in soft agar when cultured with factors released from VAT. These cells, which acquire the capacity for 3D growth, show elevated aryl hydrocarbon receptor (AhR) protein and AhR target genes, suggesting that AhR activity may drive malignant transformation by VAT. AhR is a ligand-dependent transcription factor that generates biological responses to exogenous carcinogens and to the endogenous tryptophan pathway metabolite, kynurenine. The serum kynurenine to tryptophan ratio has been shown to be elevated in patients with obesity. Herein, we demonstrate that AhR inhibitors or knockdown of AhR in MCF-10A cells prevents VAT-induced malignant transformation. Specifically, VAT-induced transformation is inhibited by Kyn-101, an inhibitor for the endogenous ligand binding site of AhR. Mass spectrometry analysis demonstrates that adipocytes metabolize tryptophan and release kynurenine, which is taken up by MCF-10A cells and activates the AhR to induce CYP1B1 and promote malignant transformation. This novel hormone receptor-independent mechanism of malignant transformation suggests targeting AhR for TNBC prevention in the context of visceral adiposity.


Subject(s)
Kynurenine , Triple Negative Breast Neoplasms , Humans , Adipocytes/metabolism , Epithelial Cells/metabolism , Hormones/metabolism , Kynurenine/metabolism , Ligands , Receptors, Aryl Hydrocarbon/metabolism , Triple Negative Breast Neoplasms/metabolism , Tryptophan/metabolism
2.
J Cardiovasc Pharmacol ; 78(2): 319-327, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34029269

ABSTRACT

ABSTRACT: Although discovered as a vasoconstrictor, 5-hydroxytryptamine (5-HT, serotonin) infused into man and rodent reduces blood pressure. This occurs primarily through activation of 5-HT7 receptors and, at least in part, venodilation. Vascular mechanisms by which this could occur include direct receptor activation leading to vasodilation and/or suppression of contractile 5-HT receptor activation. This study tests the hypothesis that the 5-HT7 receptor restrains activation of the 5-HT2A receptor. A subhypothesis is whether agonist-induced activation-independent of constitutive activity-of the 5-HT7 receptor is necessary for this restraint. The isolated abdominal aorta and vena cava from the normal male Sprague-Dawley rat was our model. Studies used real-time PCR and a pharmacological approach in the isolated tissue bath for measurement of isometric tone. Although 5-HT2A receptor mRNA expression in both aorta and vena cava was significantly larger than that of the 5-HT7 receptor mRNA, the 5-HT7/5-HT2A receptor mRNA ratio was greater in the vena cava (0.30) than in the aorta (0.067). 5-HT7 receptor antagonism by SB266970 and DR 4458 increased maximum contraction to 5-HT in the isolated vein by over 50% versus control. The 5-HT2A receptor agonists TCB-2 and NBOH were more potent in the aorta compared with 5-HT but less efficacious, serving as partial agonists. By contrast, these same three agonists caused no contraction in the vena cava isolated from the same rats up to 10 µM agonist. Antagonism of the 5-HT7 receptor by SB269970 did not increase either the potency or efficacy of TCB-2 or NBOH. These data support that the 5-HT7 receptor itself needs to be stimulated to reduce contraction and suggest there is little constitutive activity of the 5-HT7 receptor in the isolate abdominal vena cava.


Subject(s)
Aorta, Abdominal/drug effects , Receptor, Serotonin, 5-HT2A/drug effects , Receptors, Serotonin/drug effects , Serotonin Receptor Agonists/pharmacology , Serotonin/pharmacology , Vasoconstriction/drug effects , Vasodilation/drug effects , Vena Cava, Inferior/drug effects , Animals , Aorta, Abdominal/metabolism , In Vitro Techniques , Male , Rats, Sprague-Dawley , Receptor, Serotonin, 5-HT2A/genetics , Receptor, Serotonin, 5-HT2A/metabolism , Receptors, Serotonin/genetics , Receptors, Serotonin/metabolism , Serotonin Antagonists/pharmacology , Vena Cava, Inferior/metabolism
3.
Am J Physiol Renal Physiol ; 300(1): F272-82, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20962118

ABSTRACT

Angiotensin (ANG)-(1-7) constitutes an important functional end-product of the renin-angiotensin-aldosterone system that acts to balance the physiological actions of ANG II. In the kidney, ANG-(1-7) exerts beneficial effects by inhibiting growth-promoting pathways and reducing proteinuria. We examined whether a 2-wk treatment with a daily dose of ANG-(1-7) (0.6 mg·kg(-1)·day(-1)) exerts renoprotective effects in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP). Body weight, glycemia, triglyceridemia, cholesterolemia, as well as plasma levels of Na+ and K+ were determined both at the beginning and at the end of the treatment. Also, the weekly evolution of arterial blood pressure, proteinuria, and creatinine clearance was evaluated. Renal fibrosis was determined by Masson's trichrome staining. Interleukin (IL)-6, tumor necrosis factor (TNF)-α, and nuclear factor-κB (NF-κB) levels were determined by immunohistochemistry and confirmed by Western blotting analysis. The levels of glomerular nephrin were assessed by immunofluorescence. Chronic administration of ANG-(1-7) normalized arterial pressure, reduced glycemia and triglyceridemia, improved proteinuria, and ameliorated structural alterations in the kidney of SHRSP as shown by a restoration of glomerular nephrin levels as detected by immunofluorescence. These results were accompanied with a decrease in both the immunostaining and abundance of IL-6, TNF-α, and NF-κB. In this context, the current study provides strong evidence for a protective role of ANG-(1-7) in the kidney.


Subject(s)
Angiotensin I/therapeutic use , Interleukin-6/metabolism , Kidney/drug effects , NF-kappa B/metabolism , Peptide Fragments/therapeutic use , Proteinuria/drug therapy , Tumor Necrosis Factor-alpha/metabolism , Animals , Blood Pressure/drug effects , Kidney/pathology , Male , Membrane Proteins/metabolism , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Sodium Chloride/pharmacology
4.
CABA; Ministerio de salud de la nación. Programa Sumar; s.f. 24 p.
Monography in Spanish | ARGMSAL | ID: biblio-994332

ABSTRACT

El Plan Nacer es un programa federal del Ministerio de Salud de la Nación implemen»tado para invertir recursos en salud destinados a mejorar la cobertura de salud y la calidad de la atención de las mujeres embarazadas, puérperas y de los niños/as menores de 6 años que no tienen obra social. El Programa, en acuerdo con las pro»vincias, desarrolla Seguros Públicos de Salud para la población materno-infantil sin obra social, a través de un modelo de financiamiento por resultados. En función de los resultados alcanzados, el Gobierno Nacional puso en marcha en agosto del 2012 el Programa SUMAR, la ampliación del Plan Nacer. El Programa SUMAR, junto con la cobertura para la población materno-infantil, incorpora a los niños/as y adolescentes de 6 a 19 años y a las mujeres hasta los 64 años


Subject(s)
Familiar Allocations , Maternity Allocation , Health Programs and Plans
SELECTION OF CITATIONS
SEARCH DETAIL
...