Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increased blood pressure induces functional and structural changes of the vascular endothelium. Depression of endothelium-dependant vasodilatation is an early manifestation of endothelial dysfunction due to hypertension. It can be demonstrated by pharmacological or physiological tests. Decreased availability of nitric oxide (NO) is a major determinant of the depression of vasodilatation. It may be caused by a reduction in the activity of NO-endothelial synthase (NOSe) related to: 1) a deficit in substrate (L-arginine), 2) an inhibition by asymmetrical dimethylarginine, 3) a deficit in the cofactor tetrahydrobiopterin (BH4). However, the increase in oxidative stress, a producer of superoxide radicals which combine with NO to form peroxynitrates (ONOO-), is the determining factor. It is related to activation of membranous NAD(P)H oxidases initiated by the stimulation of activating mecanosensors of protein C kinase. The message is amplified by oxidation of BH4 which transforms the NOSe into a producer of superoxide radicals. A cascade of auto-amplification loops leading to atherosclerosis and its complications is then triggered. The superoxide radicals and the peroxynitrates oxidise the LDL-cholesterol. They activate the nuclear factor-kappaB which controls the genes stimulating the expression of many proteins: angiotensinogen and AT1 receptors which stimulate the sympathetic system, receptors of oxidised LDL, adhesion and migration factors (ICAM-1, VCAM-1, E-selectin and MCP-1), pro-inflammatory cytokins (interleukines and TNF-alpha), growth factors (MAP kinases), plasminogen activator inhibitor 1. The monocytes and smooth muscle cells produce metalloproteinases and pro-inflammatory cytokins which destabilise the atheromatous plaque and favourise vascular remodelling. Inshort, the endothelial dysfunction due to hypertension plays a role in a complex physiopathological process and is a marker of future cardiovascular events.
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PMID:[Hypertension, endothelial dysfunction and cardiovascular risk]. 1710 Jan 43

Pro- and anti-inflammatory cytokines and their signaling pathways play key roles in protection from and pathogenesis of mycobacterial infection, and their balance and dynamic changes may control or predict clinical outcome. Peripheral blood cells' capacity to produce proinflammatory (tumor necrosis factor alpha [TNF-alpha], interleukin-12/23p40 [IL-12/23p40], and gamma interferon [IFN-gamma]) and anti-inflammatory (IL-10) cytokines in response to Mycobacterium tuberculosis or unrelated stimuli (lipopolysaccharide, phytohemagglutinin) was studied in 93 pulmonary tuberculosis (TB) patients and 127 healthy controls from Indonesia. Their cells' ability to respond to IFN-gamma was examined to investigate whether M. tuberculosis infection can also inhibit IFN-gamma receptor (IFN-gammaR) signaling. Although there was interindividual variability in the observed responses, the overall results revealed that M. tuberculosis-induced TNF-alpha and IFN-gamma levels showed opposite trends. Whereas TNF-alpha production was higher in active-TB patients than in controls, IFN-gamma production was strongly depressed during active TB, correlated inversely with TB disease severity, and increased during therapy. By contrast, mitogen-induced IFN-gamma production, although lower in patients than in controls, did not change during treatment, suggesting an M. tuberculosis-specific and reversible component in the depression of IFN-gamma. Depressed IFN-gamma production was not due to decreased IL-12/IL-23 production. Importantly, IFN-gamma-inducible responses were also significantly depressed during active TB and normalized during treatment, revealing disease activity-related and reversible impairment in IFN-gammaR signaling in TB. Finally, IFN-gamma/IL-10 ratios significantly correlated with TB cure. Taken together, these results show that M. tuberculosis-specific stimulation of IFN-gamma (but not TNF-alpha) production and IFN-gammaR signaling are significantly depressed in active TB, correlate with TB disease severity and activity, and normalize during microbiological TB cure. The depression of both IFN-gamma production and IFN-gammaR signaling may synergize in contributing to defective host control in active TB.
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PMID:Dynamic changes in pro- and anti-inflammatory cytokine profiles and gamma interferon receptor signaling integrity correlate with tuberculosis disease activity and response to curative treatment. 1714 50

To clarify the relationship between cellular immune status and nutritive condition in periparturient dairy cows, feeding content, blood profiles, and immune condition were observed in cows from two dairy herds with different types of feed content. Immunological analyses such as leukocyte population and peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, TNF-alpha, IL-4, and IL-10, quantified by real-time RT-PCR were performed. With regard to feed content during dry periods, there were six cows in the herd with insufficient non-structural carbohydrate (NFC) intake (group I) and six cows in the herd with sufficient NFC intake (group II). Significantly lower levels of blood glucose were observed in group I between weeks -12 and 16 compared with group II. Serum cholesterol level was significantly lower in group I between weeks 2 and 10 than in group II. The numbers of CD3+ and CD4+ T cells in group I were significantly lower than those in group II in weeks 6 and 14. The numbers of CD21+ B cells were significantly lower in group I than in group II in weeks -16, -12, 2, and 10. On the other hand, the CD4+/CD8+ ratio in group II was significantly higher than group I between weeks 2 and 14. The IFNgamma/IL-4 mRNA rate in group I was significantly lower than group II in week 6. We concluded that cellular immune depression occurrs after calving in dairy cows with low nutritional status in the periparturient period.
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PMID:Comparison of two different nutritive conditions against the changes in peripheral blood mononuclear cells of periparturient dairy cows. 1714 72

Previous studies have demonstrated the presence of myocardial depression in clinical and experimental septic shock. This response is mediated, in part, through circulating TNF-alpha-induced, nitric oxide-dependent, depression of basal myocyte contractility. Other mechanisms of early myocardial dysfunction involving decreased response to adrenergic stimulation may exist. This study evaluated the presence and nitric oxide dependence of impaired adrenergic response to TNF-alpha in in vitro cardiac myocytes. The contraction of electrically paced neonatal rat cardiac myocytes in tissue culture was quantified using a closed-loop video tracking system. TNF-alpha induced depression of baseline contractility over the first 20 min of cardiac myocyte exposure. This effect was blocked by N-methyl-arginine (NMA), a nitric oxide synthase inhibitor, in all studies. Contractile and cAMP response to increasing concentrations of isoproterenol was deficient in cardiac myocytes exposed to TNF-alpha regardless of the presence of NMA. In contrast, increasing concentrations of forskolin (a direct stimulant of adenylate cyclase) and dibutyryl cAMP (a metabolically active membrane-soluble analog of cAMP) completely reversed TNF-alpha-mediated depression, though only in the presence of NMA. Forskolin-stimulated cAMP generation remained intact regardless of NMA. Increasing concentrations of exogenous calcium chloride, unlike other inotropic agents, corrected TNF-alpha-mediated defects of contractility independent of the presence of NMA. These data suggest that TNF-alpha exposure is associated with a second nitric oxide-independent but calcium-dependent early depressant mechanism that is manifested by reduced contractile and cAMP response to beta-adrenergic stimulation.
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PMID:Nitric oxide-dependent and -independent mechanisms are involved in TNF-alpha -induced depression of cardiac myocyte contractility. 1723 61

In addition to playing a central role in energy homeostasis, leptin is also an important player in the inflammatory response. Systemic inflammation is accompanied by fever (less severe cases) or hypothermia (more severe cases). In leptin-irresponsive mutants, the hypothermia of systemic inflammation is exaggerated, presumably due to the enhanced production and cryogenic action of tumor necrosis factor (TNF)-alpha. Mechanisms that exaggerate hypothermia can also attenuate fever, particularly in a cool environment. Another common manifestation of systemic inflammation is behavioral depression. Along with the production of interleukin (IL)-1beta, this manifestation is exaggerated in leptin-irresponsive mutants. The enhanced production of TNF-alpha and IL-1beta may be due, at least in part, to insufficient activation of the anti-inflammatory hypothalamo-pituitary-adrenal axis by immune stimuli in the absence of leptin signaling. In experimental animals and humans that are responsive to leptin, suppression of leptin production under conditions of negative energy balance (e.g., fasting) can exaggerate both hypothermia and behavioral depression. Since these manifestations aid energy conservation, exaggeration of these manifestations under conditions of negative energy balance is likely to be beneficial.
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PMID:Leptin: at the crossroads of energy balance and systemic inflammation. 1727 15

We have previously shown that type 2 diabetes (T2D) in the mouse is associated with increased responsivity to innate immune challenge. Here we demonstrate that in a mouse model of type 1 diabetes (T1D) LPS-dependent suppression of social exploration (SE) is augmented and dependent on hyperglycemia. T1D was induced in mice with intraperitoneal (i.p.) streptozotocin (STZ). After 4d, STZ treated mice had blood glucose levels of 417+/-34mg/dl compared to 160+/-11mg/dl in non-STZ treated mice. When these diabetic mice were challenged with i.p. lipopolysaccharide (LPS), LPS-induced depression of SE was nearly 2.7-fold greater in diabetic mice at 2h than in non-diabetic mice. Examination of peritoneal proinflammatory cytokine levels 2h after LPS administration showed that diabetic mice had 4-, 2.5- and 3.6-fold greater concentrations of IL-1beta, IL-6 and TNF-alpha, respectively, when compared to non-diabetic mice. Control of blood glucose levels with injected insulin in diabetic mice improved 2h post LPS-induced loss of SE by 3.9-fold. Interestingly, insulin given intracerebroventricularly to diabetic mice did not impact LPS-induced loss of SE but did increase basal SE 8, 12 and 24h later. Finally, administration of STZ to hyperglycemic/hyperinsulinemic db/db mice did not alter LPS-induced loss of SE. Taken together these findings indicate that mice with T1D have augmented loss of SE in response to LPS and this is due to hyperglycemia and not to insulin.
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PMID:LPS-dependent suppression of social exploration is augmented in type 1 diabetic mice. 1732 Nov 7

Morbid obesity is associated with low-grade systemic inflammation and immune activation. Thereby various pro-inflammatory cytokines like TNF-alpha, IL-1, IL-6, IFN-gamma and hormones, such as leptin are synthesized and released in human adipose tissue. The immunomodulatory enzyme indoleamine 2,3-dioxygenase (IDO) is widely distributed in mammals and is inducible preferentially by IFN-gamma. IDO degrades the essential amino acid tryptophan to form N-formyl kynurenine which, depending on cell type and enzymatic repertoires, is subsequently converted to finally form niacin. More recently, it has been proposed that activation of IDO is also critically involved in the regulation of immune responses. In obesity plasma tryptophan concentrations have been shown to be decreased and to be independent of weight reduction or dietary intake. In addition, we previously demonstrated that IDO mediated tryptophan catabolism due to chronic immune activation is the cause for such reduced tryptophan plasma levels in morbidly obese patients compared to lean individuals. Furthermore, these tryptophan metabolic changes may subsequently reduce serotonin production and cause mood disturbances, depression, and impaired satiety ultimately leading to increased caloric uptake and obesity. IDO-mediated tryptophan degradation due to chronic immune activation can therefore be considered as the driving force for food intake. We here review the potential pathogenic links between chronic immune activation and decreased IDO mediated tryptophan and serotonin levels in morbid obesity.
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PMID:Chronic immune activation underlies morbid obesity: is IDO a key player? 1743 Jan 17

In the heart, thermal injury activates a group of intracellular cysteine proteases known as caspases, which have been suggested to contribute to myocyte inflammation and dyshomeostasis. In this study, Sprague-Dawley rats were given either a third-degree burn over 40% total body surface area plus conventional fluid resuscitation or sham burn injury. Experimental groups included 1) sham burn given vehicle, 400 microl DMSO; 2) sham burn given Q-VD-OPh (6 mg/kg), a highly specific and stable caspase inhibitor, 24 and 1 h prior to sham burn; 3) burn given vehicle, DMSO as above; 4) burn given Q-VD-OPh (6 mg/kg) 24 and 1 h prior to burn. Twenty-four hours postburn, hearts were harvested and studied with regard to myocardial intracellular sodium concentration, intracellular pH, ATP, and phosphocreatine (23Na/31P nuclear magnetic resonance); myocardial caspase-1, -3,and -8 expression; myocyte Na+ (fluorescent indicator, sodium-binding benzofurzan isophthalate); myocyte secretion of TNF-alpha, IL-1beta, IL-6, and IL-10; and myocardial performance (Langendorff). Burn injury treated with vehicle alone produced increased myocardial expression of caspase-1, -3, and -8, myocyte Na+ loading, cytokine secretion, and myocardial contractile depression; cellular pH, ATP, and phosphocreatine were stable. Q-VD-OPh treatment in burned rats attenuated myocardial caspase expression, prevented burn-related myocardial Na+ loading, attenuated myocyte cytokine responses, and improved myocardial contraction and relaxation. The present data suggest that signaling through myocardial caspases plays a pivotal role in burn-related myocyte sodium dyshomeostasis and myocyte inflammation, perhaps contributing to burn-related contractile dysfunction.
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PMID:Caspase inhibition reduces cardiac myocyte dyshomeostasis and improves cardiac contractile function after major burn injury. 1743 Oct 85

Despite clinical evidence of myocardial dysfunction, there is no pathological evidence of myocardial injury in hantavirus pulmonary syndrome (HPS). The dominant opinion is that the primary cardiac lesion is functional rather than structural. The present study describes hantaviral antigen and particles in the cardiac endothelium and interstitial macrophages in association with a typical myocarditis in HPS. Human hearts from 14 individuals who died of HPS were compared with hearts from 14 individuals who died of acute necrotizing pancreatitis associated with acute lung injury and 4 individuals who died accidental deaths without thoracic injury (as controls); all cases were selected from autopsies. Transmural blocks of myocardial tissue were excised from the middle portion of the left-ventricular free wall and fixed in formalin. Small samples of myocardial tissue from 4 HPS cases and 4 non-HPS controls were fixed in glutaraldehyde for electron microscopic study. Histomorphometric, immunohistochemical, and ultrastructural methods were employed to detect the presence of hantavirus in the myocardium and to evaluate interstitial edema and the minor diameter of myocytes, to characterize the immunophenotype, and to estimate the number of inflammatory cells and in situ cytokine-producing cells and the T helper cell subset 1 and 2 immune responses (tumor necrosis factor [TNF]-alpha, interferon-gamma, interleukin [IL]-10, and IL-4). Cardiac remodeling; hantaviral antigen and particles in the endothelium and macrophages; scattered foci of myofiber necrosis; greater interstitial cellular infiltration, mainly composed of macrophages and memory T lymphocytes and a significant number of T helper and B lymphocytes; and TNF-alpha protein expression in macrophage-type cells and cardiomyocytes were observed to a greater extent in HPS myocardium than in normal and acute pancreatitis control myocardium. These findings give support to the opinion that structural changes could be responsible for myocardial depression and shock in HPS, and it should be properly named as "hantavirus cardiopulmonary syndrome" (HCPS).
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PMID:Hantavirus infection induces a typical myocarditis that may be responsible for myocardial depression and shock in hantavirus pulmonary syndrome. 1743 35

Migraine is a common disorder, characterized by recurrent episodes of headache and associated symptoms. The full pathophysiology of migraine is incompletely delineated. Current theories suggest that it is a neurovascular disorder involving cortical depression, neurogenic inflammation and vasodilation. Various neuropeptides and cytokines have been implicated in the pathophysiology of migraine including calcitonin gene-related peptide, interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF)-alpha. There is evidence demonstrating an association between migraine and processes associated with inflammation, atherosclerosis, immunity and insulin sensitivity. Similarly, adiponectin, an adipocytokine secreted by adipose tissue, has protective roles against the development of insulin resistance, dyslipidaemia and atherosclerosis and exhibits anti-inflammatory properties. The anti-inflammatory activities of adiponectin include inhibition of IL-6 and TNF-induced IL-8 formation, as well as induction of the anti-inflammatory cytokines IL-10 and IL-1 receptor antagonist. Adiponectin levels are also inversely correlated with C-reactive protein (CRP), TNF-alpha and IL-6 levels. Likewise, recent studies have shown a possible correlation between CRP, TNF-alpha and IL-6 and migraine attacks. In addition, insulin sensitivity is impaired in migraine and obesity is a risk factor for the transformation from episodic to chronic migraine. In this review we discuss the basic science of adiponectin and its potential connection to the pathophysiology of migraine. Future research may focus on how adiponectin levels are potentially altered during migraine attacks, and how that information can be potentially translated into migraine therapy.
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PMID:Migraine and adiponectin: is there a connection? 1744 81


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