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)

The expression of certain proteolytic enzymes involved in cell migration (collagenase, urokinase) can be enhanced by the disruption of cellular cytoskeletal organization, suggesting an association between cell shape and gene expression. We have examined the effect of cytoskeleton-disrupting agents on the production and secretion of another proteolytic enzyme, tissue plasminogen activator (tPA), and its inhibitor, plasminogen activator inhibitor-1 (PAI-1), in human endothelial cells. Addition of 1 x 10(-6) M colchicine, 5 x 10(-6) M cytochalasin B, 10(-6) M nocodazole, or 10(-6) M tubulazole had no effect on the constitutive rate of release of tPA. However, the three microtubule-disrupting agents--colchicine, nocodazole, and tubulazole--depressed the stimulation of tPA secretion by phorbol myristate acetate (PMA) by 50- to 65%. Disruption of microfilament structure by cytochalasin B had no effect. In contrast, microtubule disruption in the absence or presence of PMA stimulated PAI-1 secretion by 2.5 and 2 times, respectively. The depression of tPA secretion was not due to inhibition of the secretory function since tPA did not accumulate intracellularly during colchicine treatment. Nor did colchicine affect the PMA activation of protein kinase C-alpha, upon which stimulation of tPA is dependent; neither translocation of the kinase nor phosphorylation of the protein kinase C substrate protein, P80, was inhibited. Measurement of tPA mRNA levels demonstrated that the increase which precedes PMA-enhanced tPA secretion was also inhibited by colchicine by 50%. However, tPA gene transcriptional activity was only reduced 13%, suggesting that a post-transcriptional event was affected by microtubule disruption. PAI-1 mRNA levels and transcription rates were elevated 3.5 times. This study suggests that the changes that occur in endothelial cells during PMA-induced signal transmission leading to enhanced tPA mRNA levels and tPA antigen production can be partly blocked by agents that disrupt microtubule organization.
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PMID:Disruption of microtubules inhibits the stimulation of tissue plasminogen activator expression and promotes plasminogen activator inhibitor type 1 expression in human endothelial cells. 163 33

Type II (non-insulin dependent) diabetes is associated with a high incidence of vascular disease that causes morbidity and mortality. The principal organs affected by this process are the heart, brain and lower limbs. For many years it has been proposed that depression of the fibrinolytic system, which acts to maintain patency of blood vessels, may contribute to the development of vascular disease. A number of pharmacological agents have been shown to enhance circulating fibrinolytic activity of which metformin is perhaps the most interesting because of its low incidence of serious side effects. Early studies with metformin demonstrated an increase in global fibrinolytic activity in patients with coronary artery disease, peripheral vascular disease and diabetes. Recent studies using assays specific for the components of the fibrinolytic system have shown that the effects of metformin are to cause a fall in plasma levels of the fibrinolytic inhibitor, plasminogen activator inhibitor-1 (PAI-1). There is evidence to suggest that the relationship between depressed fibrinolysis and vascular disease is due to high levels of PAI-1, and reasons to believe that a lowering of PAI-1 may be beneficial in this respect. Further studies are warranted to evaluate the long term effects of metformin warranted to evaluate the long term effects of metformin on the incidence of vascular disease in diabetic patients.
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PMID:The effects of metformin on the fibrinolytic system in diabetic and non-diabetic subjects. 193 71

The fibrinolytic potential of the vasculature is modulated primarily by the availability and activity of plasminogen activators, which convert the zymogen plasminogen into the active fibrin-degrading enzyme plasmin. The activities of these key regulatory enzymes are directly neutralized by their primary endogenous inhibitor, plasminogen activator inhibitor-1 (PAI-1). Although some individuals with a tendency to develop thrombotic disorders exhibit elevated levels of PAI-1 in their plasma, the cause-and-effect relationship between increased PAI-1 and thrombosis is still unclear. Specifically, it is not known whether chronic depression of fibrinolytic activity results in the development of thrombosis. To address this question we developed transgenic mice in which the contribution of PAI-1 to thrombus formation could be evaluated. The results presented in this report indicate that elevated levels of PAI-1 contribute to the development of venous but not arterial occlusions.
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PMID:Development of venous occlusions in mice transgenic for the plasminogen activator inhibitor-1 gene. 236 66

Depression of fibrinolysis may be relevant to the vascular complications of diabetes mellitus. Plasminogen activator inhibitor (PAI) is an important inhibitor of fibrinolysis in humans, and we have found basal activities of PA inhibition to be elevated in patients with diabetes compared with a reference group of healthy subjects (mean +/- SD 268 +/- 268 vs. 105 +/- 48%; P less than .0001). With a monoclonal antibody, it was shown that high inhibition values were due to PAI-1. No differences in PA inhibition were noted in relation to type of diabetes, diabetic treatment, or presence or absence of vascular complications. Basal PA inhibition did not correlate with in vivo (B beta 15-42 antigen) or ex vivo (fibrin plate) fibrinolytic activity or HbA1. In patients with non-insulin-dependent diabetes mellitus, treatment with the anabolic steroid stanozolol significantly reduced PA inhibition. These findings suggest a further abnormality of fibrinolysis in diabetes, but the lack of a relationship among other measures of fibrinolysis renders its biologic significance uncertain.
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PMID:Tissue plasminogen activator inhibition in diabetes mellitus. 208 93

Plasminogen activator inhibitor (PAI-1), tissue type plasminogen activator (tPA) and von Willebrand factor (vWF) concentrations were measured by ELISA in the supernatant of the following cultures: endothelial cells from human umbilical vein (HUVEC); human colon cancer cells (HRT-18); and co-culture cells of HUVEC + HRT-18. No measurable amount of the three substances was found in the supernatant of HRT-18 cell culture. Compared to the value in the HUVEC supernatant, in the UVEC/HRT-18 co-cultures, tPA concentration was significantly lower (P = 0.0047), PAI-1 significantly higher (P = 0.026) and vWF also significantly higher (P = 0.0048). These data indicate that HRT-18 tumor cells do not produce tPA, PAI-1 and vWF; however, these tumor cells induce endothelial cells to change the production of these substances. As a consequence, the interaction between tumor and endothelial cells in vivo may lead to depression of fibrinolysis and enhancement of platelet adhesion.
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PMID:Expression of tissue-type plasminogen activator, plasminogen activator inhibitor and von Willebrand factor in the supernatant of endothelial cell cultures in response to the seeding of adenocarcinoma cell line HRT-18. 895 58

Elevated plasma levels of lipoprotein(a) [LP(a)] are associated with increased an risk of developing atherosclerosis. This increased risk may be due to an Lp(a)-mediated depression of fibrinolytic activity. Lp(a) regulates fibrinolysis by controlling the activity of plasminogen activators. Lp(a) is a low density lipoprotein with an apoprotein(a) subunit which has a high degree of homology with the fibrinolytic zymogen plasminogen. The apoprotein(a) subunit contains up to thirty seven copies of a domain homologous to the plasminogen kringle 4 domain, which enables Lp(a) to bind to fibrin. The subunit also has a zymogen domain, but it is not activated by plasminogen activators. Lp(a) inhibits plasminogen activation by competing with plasminogen for access to plasminogen activators bound to vascular surfaces. Lp(a) also competes with the irreversible inhibitor of plasminogen activators, plasminogen activator inhibitor-1. Therefore increases in Lp(a) concentration may decrease fibrinolytic activity by preventing activation of plasminogen, but Lp(a) may also prolong plasminogen activation by preventing the irreversible inhibition of the activators. At elevated levels of Lp(a) the decreased rate of plasmin generation may not be offset by the prolongation in plasminogen activation, and fibrinolysis will be inhibited.
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PMID:Lipoprotein (a) in the regulation of fibrinolysis. 922 22

In males, aging, health and disease are processes that occur over physiologic time and involve a cascade of hormonal, biochemical and physiological changes that accompany the down-regulation of the hypothalamic-anterior pituitary-testicular axis. As aging progresses there are relative increases of body fat and decreases in muscle mass. The increased adipose tissue mass is associated with the production of a number of newly generated factors. These include aromatase, leptin, PAI-1, insulin resistance, and the dyslipidemias, all of which can lead to tissue damage. Fatty tissue becomes the focal point for study as it represents the intersection between energy storage and mobilization. The increase in adipose tissue is associated with an increase in the enzyme aromatase that converts testosterone to estradiol and leads to diminished testosterone levels that favor the preferential deposition of visceral fat. As the total body fat mass increases, hormone resistance develops for leptin and insulin. Increasing leptin fails to prevent weight gain and the hypogonadal-obesity cycle ensues causing further visceral obesity and insulin resistance. The progressive insulin resistance leads to a high triglyceride-low HDL pattern of dyslipidemia and increased cardiovascular risk. All of these factors eventually contribute to the CHAOS Complex: coronary disease, hypertension, adult-onset diabetes mellitus, obesity and/or stroke as permanent changes unfold. Other consequences of the chronic hypogonadal state include osteopenia, extreme fatigue, depression, insomnia, loss of aggressiveness and erectile dysfunction all of which develop over variable periods of time.
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PMID:Aromatase, adiposity, aging and disease. The hypogonadal-metabolic-atherogenic-disease and aging connection. 1139 22

In a placebo-controlled, double-blinded, randomized study we evaluated the effect of ramipril prior to thrombolysis on the course of PAI-1 plasma levels and on the frequency of postinfarct ischemic events in patients with acute myocardial infarction. Fifty-one out of 99 patients received 2.5 mg ramipril orally prior to thrombolysis and 12 h later. The blood samples for determination of PAI-1 plasma levels were collected on admission and 2, 4, 8, 12 and 24 h after thrombolysis. Postinfarct ischemic events were registered until coronary angiography was performed and defined as recurrent chest pain and/or evidence of ischemic signs on the ECG (ST-depression or ST-segment elevation of 1 mm in one or more inferior or anterior leads). Coronary angiography was performed within 7 days after the onset of myocardial infarction. Patients were classified into two groups: those without reperfusion of the infarct-related artery (TIMI grade 0 or 1) and those with reperfusion of the infarct-related artery (TIMI grade 2.3). On admission, PAI-1 plasma levels were similar in both groups (ramipril: 47.1 [4.8] ng/ml; placebo: 49.1 [4.8] ng/ml). The PAI-1AUC was 77.2 [6.7] ng/ml/h in the ramipril group and 95.4 [6.2] ng/ml/h in the placebo group (p = 0.013). Significant differences between groups were observed at 4, 8 and 12 h after thrombolysis (4 h: 85.5 (11.3) vs. 116 (12.3) ng/ml, p < 0.01; 8 h: 79.1 (11.2) vs. 100.9 (9.3) ng/ml, p < 0.01; 12 hrs: 71.3 (9.5) vs. 87.4 (7.7) ng/ml, p < 0.05). The relative frequency of postinfarct ischemic events was significantly lower in the ramipril group (2.5% versus 7.1%, p = 0.001). Additionally, we observed a significant higher rate of TIMI grade 2 and 3 of the infarct-related artery in patients receiving oral ramipril compared to the placebo group (73% versus 54%; p = 0.035). Our study demonstrates a favorable effect of ramipril on the fibrinolytic system after thrombolysis associated with a lower rate of postinfarct ischemic events within the first days after myocardial infarction. Therefore, the application of ramipril prior to thrombolysis appears to be a reasonable concomitant treatment which may reduce early infarct-related complications.
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PMID:Ramipril prior to thrombolysis attenuates the early increase of PAI-1 in patients with acute myocardial infarction. 1219 84

Sepsis almost invariably leads to hemostatic abnormalities, ranging from insignificant laboratory changes to severe disseminated intravascular coagulation (DIC). There is compelling evidence from clinical and experimental studies that DIC is involved in the pathogenesis of microvascular dysfunction and contributes to organ failure. In addition, the massive and ongoing activation of coagulation, may deplete platelets and coagulation factors, which may in turn cause bleeding. Recent insights into important pathogenetic mechanisms that may lead to DIC have resulted in novel preventive and therapeutic approaches to patients with sepsis and a derangement of coagulation. Thrombin generation proceeds via the (extrinsic) tissue factor/factor VIIa route and simultaneously occurring depression of inhibitory mechanisms, such as antithrombin III and the protein C system. Also, impaired fibrin degradation, due to high circulating levels of PAI-1, contributes to enhanced intravascular fibrin deposition. Supportive strategies aimed at the inhibition of coagulation activation may be justified on theoretical grounds and have been found to be beneficial in experimental and initial clinical studies. These strategies comprise inhibition of tissue factor-mediated activation of coagulation or restoration of physiological anticoagulant pathways, by means of the administration of antithrombin concentrate or recombinant human activated protein C.
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PMID:Sepsis and disseminated intravascular coagulation. 1476 Feb 11

Depression and anxiety are prospectively associated with cardiac morbidity and mortality. Increased clotting diathesis may mediate this link. We hypothesized that there would be an association between mood and hemostatic changes that occur during and following recovery from acute mental stress. Forty-eight community-dwelling elderly subjects underwent a laboratory speech stressor task. Plasma von Willebrand factor (vWF), thrombin/antithrombin III (TAT) complexes, D-dimer, tissue-type plasminogen activator (t-PA), and type I plasminogen activator inhibitor (PAI-1) were measured at rest, after conclusion of the speech, and 14 min afterwards (recovery). Mood was assessed with the Hamilton Rating Scales for Depression (Ham-D) and Anxiety (Ham-A). Mental stress elicited a hypercoagulable state as evidenced by increases in TAT and D-dimer, and by a decrease in t-PA. Overall, hypercoagulability had increased after recovery. Ham-D scores and Ham-A scores correlated with increases in D-dimer over the testing interval (i.e. area under the curve). Ham-A (but not Ham-D) uniquely explained 8% and 17% of the variance in resting D-dimer and D-dimer area under the curve, respectively. The independent association of anxiety symptoms with resting and stress-induced fibrin formation (D-dimer) may be a mechanism linking mood with cardiovascular disease risk in the elderly.
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PMID:Effects of depressive symptoms and anxiety on hemostatic responses to acute mental stress and recovery in the elderly. 1515 51


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