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Query: UMLS:C0021051 (
immunodeficiency
)
71,517
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Development of Kaposi's sarcoma (KS) after glucocorticoid therapy has been observed in a variety of clinical states including human
immunodeficiency
virus-1 infection and recent in vitro studies provided evidence for a direct stimulation effect of glucocorticoid hormones on KS cell proliferation. The importance of glucocorticoids in KS pathogenesis is further highlighted by the finding that glucocorticoids synergize with cytokines to promote acquired immune deficiency syndrome (AIDS)-associated KS (AIDS-KS) growth. Furthermore, cytokine effects were abrogated by the glucocorticoid antagonist RU-486. As glucocorticoid action is mediated through activation of their intracellular cognate receptors, we hypothesized that enhanced responsiveness of AIDS-KS cells to glucocorticoids may be due to elevated
glucocorticoid receptor
(GR) content. Indeed, high expression of GRs in AIDS-KS tumor biopsies was detected both at the level of mRNA and protein. Quantitative measurements of GRs in these specimens by a sensitive immunoassay showed that GR content was significantly elevated in the tumor tissue (4663 fmol/mg protein) compared with the uninvolved skin of the same patients (2777 fmol/mg protein), both of which were markedly above the normal skin of healthy donors (893 fmol/mg protein). Immunocytochemical analysis confirmed the presence of GRs in the cytoplasm and the nucleus of KS cells. Interestingly, four major KS cytokines, namely interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, and oncostatin M, all of which are known autocrine growth factors for AIDS-KS cells, significantly increased the expression of functional GRs in cultured AIDS-KS cells. The latter result may explain, at least in part, the synergistic effect of glucocorticoid and oncostatin M on AIDS-KS cell proliferation. Thus, the high levels of GR expression in AIDS-KS and the up-regulation of GRs by KS-growth-promoting factors may confer enhanced and sustained sensitivity to the stimulatory effects of glucocorticoids. The data presented also provide molecular bases for therapeutic interventions targeting GRs in this disease.
...
PMID:Expression and cytokine regulation of glucocorticoid receptors in Kaposi's sarcoma. 866 84
The mechanisms for activating the hypothalamic-pituitary-adrenal (HPA) axis and the roles glucocorticoids play in the pathogenesis of chronic infectious disease are largely undefined. Using the LP-BM5 model of retrovirus-induced
immunodeficiency
, we found alterations in HPA axis function, manifested as an increase in circulating levels of adrenocorticotropic hormone and corticosterone, beginning after only 3 mo of infection. These changes occurred contemporaneously with a shift in the profile of circulating cytokines from a Th1-dominant (IFN-gamma) to Th2-dominant (IL-4, IL-10) phenotype. No significant changes in either circulating IL-1beta, IL-6, or TNF-alpha levels were observed in infected mice. Administering the N-methyl-D-aspartate receptor antagonist MK-801 to infected mice normalized plasma adrenocorticotropic hormone and corticosterone levels, indicating that glutamate was a major activator of the HPA axis. Moreover, MK-801 treatment of late-stage mice also reversed the type 1 to type 2 cytokine shift to a degree comparable or superior to treatment with the
glucocorticoid receptor
antagonist RU-486. These findings indicate that HPA axis activation during LP-BM5 retrovirus infection is mediated by the chronic hyperactivation of glutamatergic pathways in the hypothalamus. Through this mechanism, the degree of peripheral
immunodeficiency
observed in the late-stage disease is profoundly augmented.
...
PMID:Glutamate augments retrovirus-induced immunodeficiency through chronic stimulation of the hypothalamic-pituitary- adrenal axis. 1020 48
Multidrug antiretroviral regimens that include human
immunodeficiency
virus-1 (HIV-1) protease inhibitors are associated with distinct lipodystrophy, hypertriglyceridemia, hyperinsulinemia, and deposition of visceral abdominal adipose tissue. To determine whether these findings are related to abnormalities of adrenal function, we compared the hypothalamic-pituitary-adrenal axes of HIV-positive patients who had evidence of protease inhibitor-associated lipodystrophy (PIAL), control volunteers (CON), and patients with Cushing's syndrome (CS). To elucidate the metabolic consequences of the observed lipodystrophy, we measured basal serum lipids and compared glucose and insulin concentrations during an oral glucose tolerance test. Spontaneous plasma cortisol showed normal diurnal variation in PIAL. Cortisol levels were similar in CON and PIAL, and levels in these groups were less than those in CS at all times of the night or day (P < 0.005). Ovine CRH-stimulated morning plasma cortisol levels were similar in PIAL and CON. ACTH was significantly greater in PIAL than CON (P < 0.05) at 0, 15, and 30 min after CRH stimulation. Urinary free cortisol in PIAL (mean +/- SD, 76 +/- 51 nmol/day) was significant lower than those in CON (165 +/- 64 nmol/day; P < 0.001) and CS (1715 +/- 1203 nmol/day; P < 0.001). However, 17-hydroxycorticosteroid excretion was significantly greater in PIAL (43 +/- 23 micromol/day) than in CON (17 +/- 8 micromol/day; P < 0.001), although lower than that in CS (74 +/- 47 micromol/day; P < 0.01). Scatchard analysis revealed normal
glucocorticoid receptor
number and affinity in PIAL. Serum triglycerides were significantly greater in PIAL (6.57 +/- 5.63 mmol/L) than in CS (1.78 +/- 0.83 mmol/L; P < 0.001) or CON (1.36 +/- 0.84 mmol/L; P < 0.001). Although triglyceride levels were significantly correlated with body mass index for CON and CS, these were not correlated for PIAL. During an oral glucose tolerance test, similar glucose and insulin values were found in PIAL and CS that were greater (P < 0.05) than CON values at 30, 60, 90, and 120 min. We conclude that the lipodystrophy associated with use of HIV-1 protease inhibitors is a syndrome of increased intraabdominal adiposity with concomitant dyslipidemia and insulin resistance, but without total body weight gain and is distinct from any known form of hypercortisolism. Although urinary cortisol disposition seems to be altered in HIV-infected patients who are being treated with multidrug regimens that include protease inhibitors, the decreased free cortisol and increased 17-hydroxycorticosteroid excretion appear to be unlikely explanations for the observed lipodystrophy. The cause remains to be elucidated.
...
PMID:Endocrine and metabolic evaluation of human immunodeficiency virus-infected patients with evidence of protease inhibitor-associated lipodystrophy. 1037 88
Glucocorticoid gene regulation can be carried out through direct binding of
glucocorticoid receptor
to glucocorticoid responsive elements (GRE), regulating directly gene transcription and modulating some signaling pathways. The human
immunodeficiency
virus type 1 (HIV-1) expression can be activated by different immunomodulators through binding of particular nuclear factors to its long terminal repeat (LTR). In order to investigate the effect of glucocorticoids in pathways that activate HIV-1 expression, we transfected promonocyte (U937) and T lymphocyte (CEM-T4) cell lineages with a plasmid containing the chloramphenicol acetyl transferase (CAT) reporter gene under the control of the HIV-1 LTR. In U937 cells, dexamethasone (DEX) downregulates CAT expression induced by either phorbol myristate acetate (PMA), tumor necrosis factor alpha (TNFalpha) or granulocyte/macrophage-colony stimulating factor (GM-CSF). In CEM-T4 cells the CAT activity was slightly upregulated by DEX following the induction by either PMA or TNFalpha. Interestingly, in both cell lines transactivation of this reporter gene by transactivator protein (TAT) was downregulated by DEX. When the CAT gene was under control of HIV-1 enhancer isolated from its LTR background, the CAT activity induced by PMA was not affected by the presence of glucocorticoids. In all experiments, comparable data were obtained when DEX was replaced by hydrocortisone (HC). Our results show that, depending on the cell line, glucocorticoids can differently affect HIV-1 expression, probably by interfering in cellular pathways involved in virus expression. Moreover, the target of this regulation in LTR is probably not the enhancer region itself.
...
PMID:HIV-1 long terminal repeat modulation by glucocorticoids in monocytic and lymphocytic cell lines. 1050 Feb 86
The accessory Vpr protein of human
immunodeficiency
virus type 1 (HIV-1) is a promiscuous activator of viral and cellular promoters. We report that Vpr enhances expression of the
glucocorticoid receptor
-induced mouse mammary tumor virus (MMTV) promoter and of the Tat-induced HIV-1 long terminal repeat promoter by directly binding to p300/CBP coactivators. In contrast, Vpr does not bind to p/CAF or to members of the p160 family of nuclear receptor coactivators, such as steroid receptor coactivator 1a and
glucocorticoid receptor
(GR)-interacting protein 1. Vpr forms a stable complex with p300 and also interacts with the ligand-bound
glucocorticoid receptor
in vivo. Mutation analysis showed that the C-terminal part of Vpr binds to the C-terminal portion of p300/CBP within amino acids 2045 to 2191. The same p300 region interacts with the p160 coactivators and with the adenovirus E1A protein. Accordingly, E1A competed for binding to p300 in vitro. Coexpression of E1A or of small fragments of p300 containing the Vpr binding site resulted in inhibition of Vpr's transcriptional effects. The C-terminal part of p300 containing the transactivating region is required for Vpr transactivation, whereas the histone acetyltransferase enzymatic region is dispensable. Vpr mutants that bind p300 but not the GR did not activate expression of the MMTV promoter and had dominant-negative effects. These results indicate that Vpr activates transcription by acting as an adapter linking transcription components and coactivators.
...
PMID:Human immunodeficiency virus type 1 (HIV-1) accessory protein Vpr induces transcription of the HIV-1 and glucocorticoid-responsive promoters by binding directly to p300/CBP coactivators. 1220 51
The human
immunodeficiency
virus type-1 (HIV-1)-accessory protein Vpr interacts with and potentiates the activity of the
glucocorticoid receptor
(GR) and arrests the host cell cycle at the G2/M boundary. Here we report that three core components of the general transcription factor (TF) IIH, CDK7, Cyclin H, and MAT1, enhance Vpr's GR coactivator activity but inhibit its cell cycle-arresting function. A CDK7 mutant defective in kinase activity for the C-terminal tail of RNA polymerase II, which cannot form a functional TFIIH complex, did not enhance Vpr coactivator activity. Overexpression of all three TFIIH components and p300 cooperatively enhanced Vpr coactivator activity, whereas TFIIH overexpression did not potentiate the transcriptional activity of a Vpr mutant, which does not bind p300/CBP. These findings suggest that TFIIH participates in Vpr's GR coactivating activity, at a step beyond its interaction with p300/CBP.
...
PMID:Transcription factor TFIIH components enhance the GR coactivator activity but not the cell cycle-arresting activity of the human immunodeficiency virus type-1 protein Vpr. 1237 13
Glucocorticoids have a broad array of life-sustaining functions and play an important role in the therapy of many diseases. Thus, changes of tissue sensitivity to glucocorticoids may be associated with and influence the course and treatment of many pathologic states. Such tissue sensitivity changes may present on either side of an optimal range, respectively as glucocorticoid resistance or hypersensitivity, and may be generalized or tissue-specific. Familial/sporadic glucocorticoid resistance syndrome caused by inactivating mutations of the
glucocorticoid receptor
(GR) gene is a classic monogenic disorder associated with congenital, generalized glucocorticoid insensitivity, while several autoimmune, inflammatory and allergic diseases are often associated with resistance of the inflamed tissues to glucocorticoids. On the other hand, glucocorticoid hypersensitivity has been suggested in visceral obesity-related insulin resistance associated with components of the metabolic syndrome, and in the acquired immunodeficiency syndrome (AIDS) caused by human
immunodeficiency
virus type-1 (HIV-1) infection. Here, we have reviewed the molecular analyses of five familial and three sporadic cases of the familial/sporadic glucocorticoid resistance syndrome and discussed the possible contribution of newly identified molecules, such as HIV-1 accessory proteins Vpr and Tat, FLICE-associated huge protein (FLASH) and chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII), on the molecular regulation of GR activity, as well as their possible contribution to changes in tissue sensitivity to glucocorticoids in pathologic conditions.
...
PMID:Tissue glucocorticoid resistance/hypersensitivity syndromes. 1294 36
Vpr (Viral protein-R) of the Human Immunodeficiency Virus type-1 is a 14-kDa virion-associated protein, conserved in HIV-1, -2 and the Simian
Immunodeficiency
Virus (SIV). Vpr is incorporated into the virion, travels to the nucleus, and has multiple activities including promoter activation, cell cycle arrest at the G2/M transition and apoptosis induction. Through these activities, Vpr is thought to influence not only viral replication but also numerous host cell functions. These functions may be categorized in three groups depending on the domains of Vpr that support them: (1) functions mediated by the amino terminal portion of Vpr, like virion packaging; (2) functions mediated by the carboxyl terminal portion such as cell cycle arrest; and (3) functions that depend on central alpha-helical structures such as transcriptional activation, apoptosis and subcellular shuttling. Association of these activities to specific regions of the Vpr molecule appears to correlate to the host/viral molecules that interact with corresponding portion of Vpr. They include Gag, host transcription factors/coactivators such as SP1, the
glucocorticoid receptor
, p300/CREB-binding protein and TFIIB, apoptotic adenine nucleotide translocator, cyclophilin A and 14-3-3 proteins. The properties of Vpr molecule has made it difficult to assess its function and determine the true cellular interactors. Further studies on Vpr function are needed to fully assess the function of this important early regulatory molecule of HIV and other lentiviruses.
...
PMID:Partner molecules of accessory protein Vpr of the human immunodeficiency virus type 1. 1514 77
Patients infected with human
immunodeficiency
virus (HIV) have a higher risk of developing major depressive disorder (MDD) than the general population. Immunophilins FKBP51 and FKBP52 are expressed in cortical neurons and regulate the function of the
glucocorticoid receptor
(GR). Previous reports have shown that genetic variants in the FKBP5 gene encoding FKBP51 are linked to psychiatric disorders. We sought to determine whether immunophilins are upregulated in HIV infection. To determine whether FKBP52 and FKBP51 are associated with MDD and/or HIV, we compared protein and gene expression in autopsy tissues from the frontal cortical gray matter. The study cases were divided into five groups: control, MDD, MDD with psychosis, HIV(+), and HIV(+) with MDD. Gene expression and protein levels were determined by real-time PCR and Western blot analysis of fresh frozen tissues. Genotyping of previously published alleles of the FKBP5 gene was also performed. We found correlation of upregulation of both immunophilins in the HIV-infected groups. In the HIV(+) population with MDD, FKBP4 expression is significantly higher while FKBP5 is more variable. After analyzing the FKBP5 gene for single nucleotide polymorphisms, we found that rs3800373 CC genotype is more frequent in the MDD and MDD/Psychosis groups. We hypothesized that the levels of FKBP51, as modulator of the nuclear translocation of GR, would be lower in MDD. Instead, an increase in FKBP51 at both the transcript (FKBP5) and protein level correlated with MDD. Increased FKBP4 expression of correlated to HIV(+)MDD but not to HIV without MDD.
...
PMID:Differential expression of immunophilins FKBP51 and FKBP52 in the frontal cortex of HIV-infected patients with major depressive disorder. 1919 39
Major depressive disorder (MDD) is a significant cause of morbidity in people living with the human
immunodeficiency
virus (HIV). FKBP5 is a candidate gene with single-nucleotide polymorphisms (SNPs) rs1360780 and rs3800373 associated with MDD. This gene product and its relative, FKBP4, physically associate with the
glucocorticoid receptor
whose function is implicated in MDD pathophysiology. Because these genes are expressed in blood and brain and elevated in HIV infection, we explored the relationship between gene expression, genotype, and MDD symptoms. Longitudinally followed subjects (N = 57) as part of the CNS HIV AntiRetroviral Effects Research study, with diagnosed MDD and who donated blood for genotyping and gene expression analysis, were assessed. Subjects donated blood on adjacent visits with and without meeting criteria for MDD episode. Changes in clinical parameters were compared changes in gene expression. Change in FKBP5 expression correlated with change in Beck Depression Inventory (BDI) for MDD → euthymic comparison in GG genotype of rs3800373 (P = .013) and TT carriers of rs1360780 (P = .02). In euthymic → MDD comparison, GG homozygous, FKBP5 expression correlated with more severe change in BDI. Change in FKBP4 expression did not correlate with changes in clinical or depression measurements. Higher FKBP5 expression correlated with greater symptom change for GG carriers of rs3800373.
...
PMID:Correlation of major depressive disorder symptoms with FKBP5 but not FKBP4 expression in human immunodeficiency virus-infected individuals. 2072 98
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