Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two families of nuclear receptors for retinoic acid (RA) have been characterized. Members of the RAR family (types alpha, beta and gamma and their isoforms alpha 1, alpha 2, beta 1 to beta 4, and gamma 1 and gamma 2) are activated by most physiologically occurring retinoids (all-trans RA, 9-cis RA, 4oxo RA and 3,4 dihyroRA). In contrast, members of the RXR family (types alpha, beta and gamma and their isoforms) are activated by 9cis-RA only. In addition to the multiplicity of receptors, the complexity of retinoid signalling is further increased by the fact that, at least in vitro, RARs bind to their cognate response elements as heterodimers with RXRs. Moreover, RXRs can also bind, in vitro, to some DNA elements as homodimers, and are heterodimeric partners for other nuclear receptors, including TRs, VDR, PPARs and a number of orphan nuclear receptors. To evaluate the functions of the different RARs and RXRs types and isoforms, we have generated null mutant mice by targeted gene disruption in ES cells. As to the functions of RARs, we found that RAR alpha 1 and RAR gamma 2 null mutant mice are apparently normal. Mice deficient in RAR alpha or RAR gamma (i.e., all alpha or gamma isoforms disrupted) show aspects of the post-natal vitamin A deficiency (VAD) syndrome which can be cured or prevented by RA, including post-natal lethality, poor weight gain and male sterility. RAR beta 2 (and RAR beta) null mutants display a retrolenticular membrane which represents the most frequent defect of the fetal VAD syndrome. That these abnormalities were restricted to a small subset of the tissues normally expressing these receptors suggested that some degree of functional redundancy should exist in the RAR family. To test this hypothesis we then generated RAR double null mutants. RAR alpha beta, RAR alpha gamma and RAR beta gamma compound mutants exhibit all the malformations of the fetal VAD syndrome, thus demonstrating that RA is the vitamin A derivative which plays a crucial role at many different stages and in different structures during organogenesis. Interestingly, almost all the structures derived from mesenchymal neural crests cells (NCC) are affected in RAR compound mutants. As to the functions of RXRs, RXR gamma null mutants are viable, fertile and morphologically normal. In contrast, RXR alpha null fetuses display a thin ventricular wall and die in utero from cardiac failure. A myocardial hypoplasia has also been observed in some RAR compound mutants as well as in VAD fetuses. Thus, RXR alpha seems to act as an inhibitor of ventricular cardiocyte differentiation and/or as a positive regulator of their proliferation, and these functions might involve heterodimerization with RARs and activation by RA. RXR beta null mutants are viable but the males are sterile, most probably because of an abnormal lipid metabolism in the Sertoli cells. New abnormalities, absent in RXR alpha mutants, are generated in RXR alpha/RAR (alpha, beta or gamma) compound mutants. All these abnormalities are also seen in RAR double mutants as well as in VAD fetuses. In contrast, such manifestations of synergism are not observed between the RXR beta or RXR gamma and the RAR (alpha, beta or gamma) null mutations. These data strongly support the conclusion that RXR alpha/RAR heterodimers represent the main functional units of the RA signalling pathway during embryonic development. Moreover, since RXR gamma-/-/RXR beta-/-/RXR alpha +/-mutants are viable, a single allele of RXR alpha can perform most of the developmental RXR functions.
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PMID:[Genetic control of the development by retinoic acid]. 918 Nov 29

All trans-retinoic acid (ATRA) syndrome is a life-threatening complication of uncertain pathogenesis that can occur during the treatment of acute promyelocytic leukemia (APL) by ATRA. Since its initial description, however, no large series of ATRA syndrome has been reported in detail. We analyzed cases of ATRA syndrome observed in an ongoing European trial of treatment of newly diagnosed APL. In this trial, patients 65 years of age or less with an initial white blood cell count (WBC) less than 5,000/microL were initially randomized between ATRA followed by chemotherapy (CT) (ATRA-->CT group) or ATRA with CT started on day 3; patients with WBC greater than 5,000/microL received ATRA and CT from day 1; patients aged 66 to 75 received ATRA-->CT. In patients with initial WBC less than 5, 000/microL and allocated to ATRA-->CT, CT was rapidly added if WBC was greater than 6,000, 10,000, 15,000/microL by days 5, 10, and 15 of ATRA treatment. A total of 64 (15%) of the 413 patients included in this trial experienced ATRA syndrome during induction treatment. Clinical signs developed after a median of 7 days (range, 0 to 35 days). In two of them, they were in fact present before the onset of ATRA. In 11 patients, they occurred upon recovery from the phase of aplasia due to the addition of CT. Respiratory distress (89% of the patients), fever (81%), pulmonary infiltrates (81%), weight gain (50%), pleural effusion (47%), renal failure (39%), pericardial effusion (19%), cardiac failure (17%), and hypotension (12%) were the main clinical signs, and 63 of the 64 patients had at least three of them. Thirteen patients required mechanical ventilation and two dialysis. A total of 60 patients received CT in addition to ATRA as per protocol or based on increasing WBC; 58 also received high dose dexamethasone (DXM); ATRA was stopped when clinical signs developed in 30 patients. A total of 55 patients (86%) who experienced ATRA syndrome achieved complete remission (CR), as compared with 94% of patients who had no ATRA syndrome (P = .07) and nine (14%) died of ATRA syndrome (5 cases), sepsis (2 cases), leukemic resistance (1 patient), and central nervous system (CNS) bleeding (1 patient). None of the patients who achieved CR and received ATRA for maintenance had ATRA syndrome recurrence. No significant predictive factors of ATRA syndrome, including pretreatment WBC, could be found. Kaplan Meier estimates of relapse, event-free survival (EFS), and survival at 2 years were 32% +/- 10%, 63% +/- 8%, and 68% +/- 7% in patients who had ATRA syndrome as compared with 15% +/- 3%, 77% +/- 2%, and 80% +/- 2% in patients who had no ATRA syndrome (P = .05, P = .003, and P = .03), respectively. In a stepwise Cox model that also included pretreatment prognostic variables, ATRA syndrome remained predictive for EFS and survival. In conclusion, in this multicenter trial where CT was rapidly added to ATRA in case of high or increasing WBC counts and DXM generally also used at the earliest clinical sign, the incidence of ATRA syndrome was 15%, but ATRA syndrome was responsible for death in only 1.2% of the total number of patients treated. However, occurrence of ATRA syndrome was associated with lower EFS and survival.
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PMID:Incidence, clinical features, and outcome of all trans-retinoic acid syndrome in 413 cases of newly diagnosed acute promyelocytic leukemia. The European APL Group. 976 54

Mouse embryos lacking the retinoic acid receptor RXRalpha properly undergo the early steps of heart development, but then fail to initiate a proliferative expansion of cardiomyocytes that normally results in the formation of the compact zone of the ventricular chamber wall. RXRalpha(-/-) embryos have a hypoplastic ventricular chamber and die in midgestation from cardiac insufficiency. In this study, we have investigated the underlying mechanistic basis of this phenotype. We find that interference with retinoic acid receptor function in the epicardium of transgenic embryos recapitulates the hypoplastic phenotype of RXRalpha deficient embryos. We further show that wild type primary epicardial cells, and an established epicardial cell line (EMC cells), secrete trophic protein factors into conditioned media that stimulate thymidine incorporation in primary fetal cardiomyocytes, and thymidine incorporation, cell cycle progression, and induction of cyclin D1 and E activity in NIH3T3 cells. In contrast, primary epicardial cells derived from RXRalpha(-/-) embryos and an EMC subline constitutively expressing a dominant negative receptor construct both fail to secrete activity into conditioned media. The production of trophic factors is induced by retinoic acid treatment and is inhibited by a retinoid receptor antagonist. Fetal atrial and ventricular myocytes both respond to epicardial-derived trophic signaling, although postnatal cardiomyocytes are nonresponsive. We therefore propose that the fetal epicardium, in response to retinoic acid and in a manner requiring the activity of RXRalpha, secretes trophic factors which drive fetal cardiomyocyte proliferation and promote ventricular chamber morphogenesis.
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PMID:Epicardial induction of fetal cardiomyocyte proliferation via a retinoic acid-inducible trophic factor. 1229 6

Endothelins are a family of three peptides of 21 amino acids with strong vasoconstrictor effects. The three peptides are encoded by three different genes and derived from precursors (" big endothelins") which are cleaved by metalloproteases, named endothelin-converting enzyme. Two receptors have been cloned, ET-A and ET-B which bind the three endothelins with various affinities. The diverse expression pattern of the endothelin system (ET) components is associated with a complex pharmacology and its counteracting physiological actions. New modulators of the ET system have been described : retinoic acid, leptin, prostaglandins, hypoxia. Endothelins can be considered as regulators working in paracrine and autocrine fashion in a variety of organs in different cellular types. The ET system has beneficial and detrimental roles in mammals. The different components have been shown to be essential for a normal embryonic and neonatal development, for renal homeostasis and maintenance of basal vascular tone. They are involved in physiological and tumoral angiogenesis. They affect the physiology and pathophysiology of the liver, muscle, skin, adipose tissue and reproductive tract. The endothelin system participates in the development of atherosclerosis as well as pulmonary hypertension, and mediates cardiac remodeling in heart failure. Elaboration of new animal models (knock-out, pathophysiological models em leader ) will allow the clear genetic dissection of physiological and pathophysiological roles of the endothelin system.
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PMID:[What is the role of endothelin system?]. 1506 80

Cardiogenesis, one of the earliest and most complex morphogenetic events in the embryo, is not fully understood at the molecular level and is typically a low-yield process. Affording a high throughput of cardiogenesis from a suitable population of pluripotent cells is therefore a major assignment in the perspective of a stem cell therapy for heart failure. Analysis of cardiac lineage commitment in mouse embryonic stem cells and in vivo models of cardiac differentiation revealed that a number of crucial growth factors are released from precursor cells, acting in an autocrine fashion on specific plasma membrane receptors to prime a cardiogenic decision. Nevertheless, it is increasingly becoming evident that cell nuclei harbor the potential for intrinsic signal transduction pathways. The term "intracrine" has been proposed for growth regulatory peptides that have been shown to act within their cell of synthesis at the level of the nuclear envelope, chromatin, or other subnuclear components. Considerable evidence links known intracrines with transcriptional responses and self-sustaining loops that behave as long-lived signals and impart features characteristic of differentiation, growth regulation and cell memory. This review focuses on a number of autocrine and intracrine systems within the context of cardiac differentiation and emphasizes the identification of cardiogenic mechanisms as a clue for the development of unprecedented differentiating strategies. In this regard, recently synthesized mixed esters of hyaluronan with butyric and retinoic acid primed the expression of cardiogenic genes and elicited a remarkable increase in cardiomyocyte yield in mouse embryonic stem cells. This demonstrates the potential for chemically modifying the gene program of cardiac differentiation without the aid of gene transfer technologies and sets the basis for the design of a novel generation of chemicals suited for the organization of targeted lineage patterning in stem cells.
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PMID:Autocrine and intracrine signaling for cardiogenesis in embryonic stem cells: a clue for the development of novel differentiating agents. 1637 Mar 27

We report on a three-drug myeloablative regimen designed to consolidate remission and to prevent central nervous system (CNS) relapse of high-risk neuroblastoma (NB). Sixty-six NB patients received topotecan 2 mg/m2/day, x 4 days; thiotepa 300 mg/m2/day, x 3 days; and carboplatin approximately 500 mg/m2/day, x 3 days. Post-SCT treatments included radiotherapy, immunotherapy, 13-cis-retinoic acid, +/-oral etoposide. Significant nonhematologic toxicities were mucositis and skin-related in all patients, convulsions in three patients, and cardiac failure and venocclusive disease of liver in one patient each. Grade 2 hepatotoxicity led to truncating cytoreduction in two patients; both later relapsed in brain. Among 46 patients transplanted in first complete/very good partial remission (CR/VGPR), event-free survival is 54% (s.e.+/-8%) at 36 months post-SCT; notable events were three non-NB-related deaths (adenovirus on day +9, bowel necrosis at 5 months, multiorgan failure at seven months) and four relapses in brain. Of 12 patients transplanted with evidence of NB, two became long-term event-free survivors and two relapsed in the brain. Of eight patients transplanted in second or greater CR/VGPR, one became a long-term event-free survivor and seven relapsed though not in the CNS. This regimen has manageable toxicity but does not prevent CNS relapse.
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PMID:Topotecan, thiotepa, and carboplatin for neuroblastoma: failure to prevent relapse in the central nervous system. 1640 Mar 36

All-trans-retinoic acid (ATRA) combined with anthracyclines is currently the standard treatment for acute promyelocytic leukemia (APL). In elderly patients the presence of comorbidities, such as cardiomyopathy or different organ failures, often represents an absolute contraindication to standard chemotherapy. In this particular setting of patients, alternative front-line approaches are needed. Here we report the use of gemtuzumab ozogamicin as consolidation therapy in a 68-year-old patient not eligible for standard dose anthracycline due to severe cardiac failure and chronic anticoagulant therapy, affected by low-risk APL. Induction therapy was started with ATRA alone, at a dose of 45 mg/m2 for 80 days. The patient obtained a complete hematological and molecular remission. At day +170 the patient was treated with 6 mg/m2 gemtuzumab ozogamicin monthly for two months (2 total doses) as a consolidation therapy and then started a maintenance program with ATRA 45 mg/m2 for 15 days every three months, for a total time of two years. No adverse events were observed in every phase of treatment and the patient is still in complete continuous hematological and molecular remission 29 months from diagnosis. This approach represents an intriguing therapeutic option to be investigated in randomized studies in low- and intermediate-risk elderly patients (older than 65 years), aiming to minimize or to eliminate standard chemotherapy in advantage of new non-conventional agents, including ATO.
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PMID:Combination of all-trans-retinoic acid and gemtuzumab ozogamicin in an elderly patient with acute promyelocytic leukemia and severe cardiac failure. 1716 40

We have developed a mixed ester of hyaluronan with butyric and retinoic acid (HBR) that acted as a novel cardiogenic/vasculogenic agent in human mesenchymal stem cells isolated from bone marrow, dental pulp, and fetal membranes of term placenta (FMhMSCs). HBR remarkably enhanced vascular endothelial growth factor (VEGF), KDR, and hepatocyte growth factor (HGF) gene expression and the secretion of the angiogenic, mitogenic, and antiapoptotic factors VEGF and HGF, priming stem cell differentiation into endothelial cells. HBR also increased the transcription of the cardiac lineage-promoting genes GATA-4 and Nkx-2.5 and the yield of cardiac markerexpressing cells. These responses were notably more pronounced in FMhMSCs. FMhMSC transplantation into infarcted rat hearts was associated with increased capillary density, normalization of left ventricular function, and significant decrease in scar tissue. Transplantation of HBR-preconditioned FMhM-SCs further enhanced capillary density and the yield of human vWF-expressing cells, additionally decreasing the infarct size. Some engrafted, HBR-pretreated FMhMSCs were also positive for connexin 43 and cardiac troponin I. Thus, the beneficial effects of HBR-exposed FMhMSCs may be mediated by a large supply of angiogenic and antiapoptotic factors, and FMhMSC differentiation into vascular cells. These findings may contribute to further development in cell therapy of heart failure.
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PMID:Hyaluronan mixed esters of butyric and retinoic Acid drive cardiac and endothelial fate in term placenta human mesenchymal stem cells and enhance cardiac repair in infarcted rat hearts. 1736 74

Cardiotonic steroids (CTS) like ouabain are not only specific inhibitors of the sodium pump (Na(+),K(+)-ATPase), they also can influence various cytosolic signaling events in a hormone-like manner. In the neuroblastoma cell line SH-SY5Y ouabain triggers multiple signaling pathways. Within 30 min of incubation with 1 or 10 microM ouabain, SH-SY5Y cells generate reactive oxygen species to a level approximately 50% above control and show a modest but significant elevation in cytosolic [Ca(2+)] of about 25%. After 6 h of exposure, ouabain stimulates a series of anti-apoptotic actions in SH-SY5Y cells, including concentration-dependent phosphorylation of Erk1/2, Akt, and Bad. Nevertheless, at the same time this CTS also induces a series of events that inhibit retinoic acid-induced neuritogenesis and promote cell death. Both of these latter phenomena are possibly associated with the observed ouabain-induced reduction in the abundance of the anti-apoptotic proteins Bcl-XL and Bcl-2. In addition, ouabain treatment results in cytochrome c release into the cytosol and induces activation of caspase 3, events that point towards the stimulation of apoptotic pathways that are probably enhanced by the stimulation of p53 phosphorylation at Ser15 also observed in this study. These pathways may eventually lead to cell death: treatment with 10 nM ouabain results in a 20% decrease in cell number after 4 days of incubation and treatment with 1 microM ouabain decreases cells number by about 75%. The results obtained here emphasize the importance of further research in order to elucidate the various signalling cascades triggered by ouabain and possibly other CTS that are used in the treatment of heart failure and to identify their primary receptor(s).
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PMID:Ouabain activates signaling pathways associated with cell death in human neuroblastoma. 1752 49

Cardiomyocyte apoptosis has an important role in the transition from compensatory cardiac remodeling to heart failure. All-trans retinoic acid (RA), a bioactive vitamin A derivative, prevents stretch- and angiotensin II (Ang II)-induced cardiac hypertrophy. However, the anti-apoptotic potential of RA in the heart remains unexplored. Here, we demonstrate that stretch- and Ang II-induced apoptosis is prevented by RA in neonatal cardiomyocytes. RA improved mitochondrial function by inhibiting the stretch- and Ang II-induced reduction in mitochondrial membrane potential, cytochrome c release and by increasing the Bcl2/Bax ratio. RA inhibited stretch- and Ang II-induced intracellular reactive oxygen species (ROS) generation and upregulated the SOD2 level. Hydrogen peroxide-induced increases in the number of TUNEL-positive cells and percentage of Annexin V positive cells, were dose-dependently inhibited by RA. The thiol antioxidant, N-acetyl cysteine (NAC), completely inhibited stretch- and Ang II-induced apoptosis. Using diazoxide (mitochondrial ATP-sensitive K(+) channel opener) and SDS (NADPH oxidase activator), we confirmed that RA suppressed both mitochondrial- and NADPH oxidase-derived ROS. We also observed that both RAR and RXR were involved in preventing Ang II- and stretch-induced ROS production and apoptosis, by using selective retinoid receptor agonists and antagonists. Our data provide the first evidence that RA prevents Ang II and stretch induced apoptosis, by inhibiting ROS generation and increasing the anti-oxidant defense system, suggesting that RA-mediated signaling may provide a new therapeutic target for the prevention of the cardiac remodeling process.
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PMID:All-trans retinoic acid prevents angiotensin II- and mechanical stretch-induced reactive oxygen species generation and cardiomyocyte apoptosis. 1794 Oct 88


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