Effects of body composition on the procoagulant imbalance in obese patients.

Obesity is associated with increased thrombotic risk and hypercoagulability whose main driver is an excess of coagulation factor VIII relative to protein C. The aims of this study were to evaluate the association between factor VIII, protein C, factor VIII-to-protein C ratio and bioimpedance parameters of body composition in obese patients. We analysed blood from 69 obese patients and 23 non-obese healthy controls. Plasma levels of factor VIII, protein C, and factor VIII-to-protein C ratio were correlated with total fat, visceral fat, and muscle mass. Compared to controls, obese patients had significantly higher factor VIII (110.5% vs 78.05%, p < 0.001), protein C (120.99% versus 110.51%, p = 0.014), and factor VIII-to-protein C ratio (0.93 versus 0.73, p = 0.002). In obese patients, factor VIII correlated with body-mass index, body fat percentage, muscle mass percentage, and fat-to-muscle ratio, whereas protein C had significant relationships with body fat percentage, muscle mass percentage and fat-to-muscle ratio, but not with body-mass index. Factor VIII-to-protein C ratio > 1 was significantly associated with body-mass index (odds ratio 1.08, 95% CI 1.02 to 1.14) and fat-to-muscle ratio (odds ratio 2.47, 95% CI 1.10 to 5.55). Factor VIII-to-protein C ratio strongly correlated with D-dimer levels in the overall population (rho 0.44, p < 0.001) and obese patients (rho 0.41, p < 0.001). In obese patients, bioimpedance measures of body fat and muscle mass percentage were associated with factor VIII and protein C. Factor VIII-to-protein C ratio was strongly associated with fat-to-muscle ratio and only modestly related to BMI.

Venous thromboembolism in cancer patients receiving neoadjuvant chemotherapy: a systematic review and meta-analysis.

Essentials Cancer patients are at risk for venous thromboembolism (VTE). The risk of VTE in less advanced stage cancer on neoadjuvant chemotherapy is unclear. In over 7800 patients, we found a 7% pooled incidence of VTE during neoadjuvant therapy. Highest VTE rates were observed in patients with bladder and esophageal cancer. SUMMARY: Background Venous thromboembolism (VTE) is a frequent complication in cancer patients receiving adjuvant treatment. The risk of VTE during neoadjuvant chemo-radiotherapy remains unclear. Objectives This systematic review evaluated the incidence of VTE in patients with cancer receiving neoadjuvant treatment. Methods MEDLINE and EMBASE databases were searched from inception to October 2017. Search results were supplemented with screening of conference proceedings of the American Society of Clinical Oncology (2009-2016) and the International Society of Thrombosis and Haemostasis (2003-2016). Two review authors independently screened titles and abstracts, and extracted data onto standardized forms. Results Twenty-eight cohort studies (7827 cancer patients, range 11 to 1398) were included. Twenty-five had a retrospective design. Eighteen cohorts included patients with gastrointestinal cancer, representing over two-thirds of the whole study population (n = 6002, 78%). In total, 508 of 7768 patients were diagnosed with at least one VTE during neoadjuvant treatment, for a pooled VTE incidence of 7% (95% CI, 5% to 10%) in the absence of substantial between-study heterogeneity. Heterogeneity was not explained by site of cancer or study design characteristics. VTE presented as pulmonary embolism in 22% to 96% of cases (16 cohorts), and it was symptomatic in 22% to 100% of patients (11 cohorts). The highest VTE rates were observed in patients with bladder (10.6%) or esophageal (8.4%) cancer. Conclusions This review found a relatively high incidence of VTE in cancer patients receiving neoadjuvant therapy in the presence of some between-study variation, which deserves further evaluation in prospective studies.

Non-O blood group and outcomes of in vitro fertilization.

PURPOSE: Retrospective and cross-sectional studies suggested that non-O blood group may be associated with failures of in vitro fertilization (IVF), but data remain controversial. The aim of this observational cohort study was to prospectively evaluate the effect of non-O blood type on clinical outcomes of IVF. METHODS: Women < 40 years who underwent IVF and had ABO blood type recorded as part of the routine workup were eligible. The primary study outcome was live birth. Secondary outcomes included spontaneous abortion, positive pregnancy test, and clinical pregnancy. RESULTS: A total of 497 women with a mean age of 34.6 (standard deviation 3.2) years were included. The mean number of embryos transferred was 2.3 (standard deviation 0.6). The most common ABO blood types were O (n = 213, 42.9%) and A (n = 203, 40.8%), while 63 (12.7%) and 18 (3.6%) women had the B and AB blood types, respectively. Differences in live birth (21.8 vs. 24.3%, odds ratio [OR] 1.17; 95% confidence intervals [CI], 0.76 to 1.78), positive pregnancy test (37.9 vs. 36.6%, OR 0.96; 95% CI, 0.66 to 1.38), clinical pregnancy (35.1 vs. 33.8%, OR 0.95; 95% CI, 0.66 to 1.39), and spontaneous abortion (12.3 vs. 9.2%, OR 0.72; 95% CI, 0.41 to 1.29) between women with O and non-O blood type were not statistically significant. CONCLUSIONS: In a prospective cohort study, we confirmed the lack of a significant association between non-O blood type and clinical outcomes of IVF. Further studies are needed to clarify whether non-O blood group has any prognostic relevance in women undergoing IVF.

Current management strategies and long-term clinical outcomes of upper extremity venous thrombosis.

UNLABELLED: Essentials Few data exist on outcome of upper extremity deep and superficial vein thrombosis (UEDVT and UESVT). We followed 102 and 55 patients with UEDVT or UESVT, respectively, for a median of 3.5 years. Risk of recurrent venous thromboembolism was low in both diseases, and the mortality high. Postthrombotic symptoms were infrequent and cancer patients had a higher risk of recurrent VTE. SUMMARY: Background There is scant information on the optimal management and clinical outcome of deep and superficial vein thrombosis of the upper extremity (UEDVT and UESVT). Objectives To explore treatment strategies and the incidence of recurrent venous thromboembolism (VTE), mortality, postthrombotic symptoms, and bleeding in patients with UEDVT and UESVT and to assess the prognosis of cancer patients with UEDVT. Patients/methods Follow-up of patients with UEDVT or UESVT, who were enrolled previously in a diagnostic management study. Results We followed 102 and 55 patients with UEDVT and UESVT, respectively, both for a median of 3.5 years. Anticoagulant treatment was started in 100 patients with UEDVT (98%) and in 40 (73%) with UESVT. Nine patients with UEDVT (9%) developed recurrent VTE, 26 (26%) died, 6 (8%) of 72 patients had moderate postthrombotic symptoms, and 5 (5%) experienced major bleeding. One patient with UESVT had a recurrent VTE, 18 (33%) died, none had moderate postthrombotic symptoms, and none had major bleeding. Of the cancer patients with UEDVT, 18% had recurrent VTE vs. 7.5% in non-cancer patients (adjusted hazard ratio 2.2, 95%CI 0.6-8.2). The survival rate was 50% in cancer patients with UEDVT vs. 60% in those without (adjusted HR 0.8, 95%CI 0.4-1.4). Conclusions The risk of recurrent VTE was low in patients with UEDVT, and negligible for UESVT. Mortality was high for both diseases. Postthrombotic symptoms were infrequent and mild. Anticoagulant therapy of UEDVT carried a substantial risk of major bleeding. Cancer patients had a significant risk of recurrent VTE.

Inhibition of P-glycoprotein-mediated transport by S-adenosylmethionine and cynarin in multidrug-resistant human uterine sarcoma MES-SA/Dx5 cells.

Multidrug resistance (MDR) to anticancer chemotherapy is often mediated by the overexpression of the plasma membrane drug transporter P-glycoprotein (Pgp) encoded by multidrug resistance gene (MDR1). Various chemosensitizing agents are able to inhibit Pgp activity but their clinical application is limited by their toxicity. Furthermore, hepatotoxicity related to chemotherapy causes delays of treatment in cancer patients and often requires supplementation of anti-tumour therapy with hepatoprotective agents. In this in vitro study, we investigated the effectiveness of an endogenous hepatoprotective agent, S-adenosylmethionine (SAMe), and a natural hepatoprotective compound, Cynarin (Cyn), to inhibit Pgp activity in order to evaluate their potential use as chemosensitizing agents. Human doxorubicin (doxo) resistant uterine sarcoma cells (MES-SA/Dx5) expressing high levels of Pgp were treated with two hepatoprotectors at various concentrations (1, 5 and 10 microM) that are clinically achievable, in the presence or absence of three different concentrations of doxo (2, 4 and 8 microM). In order to evaluate the effects of both hepatoprotectors, we measured the intracellular accumulation and cytotoxicity of doxo, the cellular GSH level, ROS production and catalase (CAT) activity. We found that treatment with 2, 4 and 8 microM doxo in the presence of SAMe or Cyn significantly increased the doxo accumulation and cytotoxicity on MES-SA/Dx5 cells, when compared to control cells receiving doxo alone. Moreover, treatment with SAMe or Cyn significantly increased GSH content, greater than 80 percent and 60 percent, respectively) and CAT activity greater than 60 and 150 percent, respectively) in resistant cancer cells, while ROS production was below the values of corresponding untreated control cells. Our in vitro findings provide a rationale for the potential clinical use of these hepatoprotectors both as chemosensitizing agents, to reverse Pgp-mediated MDR, and as antioxidants to protect normal cells from chemotherapy-induced cytotoxixity.

The effect of the plasticizer diethylhexyl phthalate on transport activity and expression of P-glycoprotein in parental and doxo-resistant human sarcoma cell lines.

Multidrug resistance (MDR) to cancer therapy is frequently associated with the over-expression of the multidrug transporter MDR1 gene product P-glycoprotein (Pgp) in several types of human tumours. Various chemosensitizers have been used to inhibit Pgp activity but toxicity limits their clinical application. Di(2-ethylhexyl)phthalate (DEHP) is a plasticizer that is released from polyvinyl chloride (PVC) medical devices. Therefore, cancer patients undertaking chemotherapy are exposed to a clinically important amount of DEHP through blood and blood component transfusions, apheresis products, intravenous chemotherapy, parenteral nutrition and other medical treatments. The present study was designed to investigate the effects of DEHP on transport activity and expression of Pgp in order to evaluate its potential use as a chemosensitizer in cancer therapy. Human doxorubicin (doxo) resistant sarcoma cells (MES-SA/Dx5) that over-express Pgp were treated with different doses of doxo (2, 4 and 8 µM) in the presence or absence of various concentrations of DEHP (3, 6 and 12 µM) that were clinically achievable in vivo. Our results show that co-treatment with 2, 4 and 8 µM doxo in the presence of the lowest concentration of DEHP (3 µM) enhanced significantly doxo accumulation in MES-SA/Dx5 cells and, consistently increased the sensitivity to doxo, when compared to controls receiving only doxo. In contrast, higher DEHP concentrations (6 and 12 µM) induced MES-SA/Dx5 to extrude doxo decreasing doxo cytotoxicity toward resistant cells below control values. These results are consistent with the increase in Pgp expression levels in parental MES-SA cells treated with 3, 6 and 12 µM DEHP for 24 h and compared to untreated controls. All in all, these findings suggest a potential clinical application of DEHP as a chemosensitizer to improve effectiveness of the antineoplastic drugs in MDR human tumours.

Accuracy of diagnostic tests for clinically suspected upper extremity deep vein thrombosis: a systematic review.

BACKGROUND: The best available test for the diagnosis of upper extremity deep venous thrombosis (UEDVT) is contrast venography. The aim of this systematic review was to assess whether the diagnostic accuracy of other tests for clinically suspected UEDVT is high enough to justify their use in clinical practise and to evaluate if any test can replace venography. METHODS: MEDLINE and EMBASE databases were searched from inception to June 2009. Two reviewers independently evaluated study eligibility, extracted data, and assessed study quality. RESULTS: We identified 17 papers, reporting on 793 patients. Overall, the methodological quality was poor, sample sizes were small, and large between-study differences were observed in spectrum and design. The summary estimates of sensitivity (95% confidence interval) were 97% (90-100%) for compression ultrasonography, 84% (72-97%) for Doppler ultrasonography, 91% (85-97%) for Doppler ultrasonography with compression, and 85% (72-99%) for phleboreography. The corresponding summary estimates of specificity were, respectively, 96% (87-100%), 94% (86-100%), 93% (80-100%), and 87% (71-100%). Clinical findings, a clinical score, D-dimer, magnetic resonance imaging, rheography and plethysmography were evaluated in one study each, involving a median number of 46 patients (range 21-214). Sensitivity and specificity ranged from 0% to 100% and from 14% to 100%. CONCLUSIONS: Methodological limitations, large between-study differences and small sample sizes limit the evidence of tests for clinically suspected UEDVT. Compression ultrasonography may be an acceptable alternative to venography. The addition of (color) Doppler does not seem to improve the accuracy. Adequately designed studies are warranted to confirm these findings.

Leptin induces tissue factor expression in human peripheral blood mononuclear cells: a possible link between obesity and cardiovascular risk?

BACKGROUND: Obesity is a major modifiable risk factor for cardiovascular disease. Leptin, the hormone synthesized and released primarily by adipose tissue and found increased in obese individuals, has been implicated in the regulation of inflammation and arterial and venous thrombosis. OBJECTIVE: To investigate the role of tissue factor (TF), the pivotal agonist of the clotting cascade, as a link between obesity and cardiovascular disease. METHODS AND RESULTS: In 15 obese patients, plasma levels of leptin and TF as well as TF expression in resting and endotoxin-stimulated mononuclear leukocytes (MN) were increased when compared with healthy donors. In a selected sample of obese patients, loss of body weight led to decreased circulating leptin levels, accompanied by a reduction in plasma TF as well as in TF expression, both in resting and endotoxin-stimulated MN. In subsequent in vitro experiments, leptin was incubated with MN from healthy subjects. Leptin induced TF activity and antigen in a dose-dependent fashion, as assessed by clotting assay and ELISA, respectively. Increased migration of c-Rel/p65 into the nucleus, as determined by EMSA, and development of TF mRNA in monocytes, as assessed by RT-PCR, were observed. Experiments with mitogen-activated protein kinase (MAPK) inhibitors, indicated the involvement of p38 and ERK1/2 pathways. CONCLUSIONS: The presence of TF-expressing MN in blood from obese subjects and the in vitro induction of TF by pharmacologic concentrations of leptin in MN from healthy subjects suggest that TF expression by leptin-stimulated monocytes may contribute to the cardiovascular risk associated with obesity.

Microsatellite polymorphism of the human leptin gene (LEP) and risk of cardiovascular disease.

BACKGROUND: No data have been so far reported on the relationship between polymorphisms of LEP gene and cardiovascular disease. PATIENTS AND METHODS: We genotyped a tetranucleotide repeat mapped in the 3'UTR of the LEP gene (LEP-tet) in 109 subjects with cardiovascular events and in 109 control subjects. RESULTS: Univariate analysis and multivariate logistic regression analysis adjusted for age, gender, smoking status, history of hyperlipidemia, hypertension or diabetes showed not significant association between the genotype of the LEP-tet and cardiovascular diseases. Moreover, no differences were observed in the plasma leptin concentrations between cases and control subjects (22 +/- 19 vs 22 +/- 14 ng/ml, P = 0.52) and in relation to the LEP-tet classes or carriage of specific alleles (P = 0.76 for the association between LEP-tet classes and leptin levels in overall analysis). CONCLUSIONS: In conclusion, our data do not support an association between the LEP-tet microsatellite polymorphism of the human LEP gene and cardiovascular diseases.

Effect of lipid-lowering treatment on factor VII profile in hyperlipidemic patients.

A link has been suggested between blood lipids and hemostatic activation. Factor VII (FVII) is a coagulation factor which plays a pivotal role in fibrin generation and thrombus formation. Clinical trials have demonstrated that inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase greatly reduce cardiovascular events in patients with and without coronary artery disease but few data, at this time, are available on the effects of lipid-lowering treatment on factor VII levels. We studied thirty-six IIA and IIB type hyperlipidemic patients who, after a preliminary period of lipid-lowering diet, added atorvastatin (20 mg/daily) or continued dietary treatment alone until they achieved LDL-C recommended levels (<4 mmol/L). Four to six weeks of lipid lowering treatment with diet plus atorvastatin, produced a significant reduction in FVII coagulant activity (FVIIc) and antigen (FVIIAg). No significant changes were observed in activated FVII (FVIIa). The lipid-lowering treatment with diet alone induced an improved lipid pattern, but no significant changes in FVII profile. Our study suggests a significant effect of lipid-lowering treatment on FVII levels. A possibile nonlipid mechanism that modifies FVII pathway may be suggested.

Increased type II transforming growth factor-beta receptor expression in liver cells during cholesterol challenge.

A large body of evidences implicates transforming growth factor-beta (TGF-beta) in the pathogenesis of atherosclerosis. In this context, TGF-beta receptor dysfunction has been suggested to be relevant. We tested the effect of hypercholesterolemia, a well-known risk factor for atherosclerosis, on liver type II TGF-beta receptor (TbetaR-II) expression in atherosclerosis-susceptible C57BL/6 mouse strain fed atherogenic diet. In addition, the relationship between cholesterol and TbetaR-II expression was verified by cholesterol challenge on human hepatoma cell (HepG2) cultures. The susceptible C57BL/6 mice fed atherogenic diet exhibited significant mRNA and immunohistochemical TbetaR-II liver expression at 2, 5, 9 and 15 weeks as compared to animals fed a regular diet. The TbetaR-II profile on HepG2 resulted in a time-dependent increased expression when the cells were incubated with soluble free cholesterol, associated with an increased TGF-beta-dependent biological activity as detected by luciferase assay of reporter gene. These data provide evidence for a cholesterol-dependent TbetaR-II induction that may play a potentially relevant role in the development of hypercholesterolemia and atherogenesis.

Expression of interleukin 8 (IL-8) and substance P in human chronic pancreatitis.

BACKGROUND: Changes in substance P content and a relationship between the degree of perineural inflammation and pain has been demonstrated in chronic pancreatitis. Whether a relationship exists between neural alteration and pancreatic inflammation (neurogenic inflammation) is not known. AIMS: In the present study we evaluated gene expression of preprotachykinin A (PPT-A), the gene encoding substance P, and interleukin 8, a proinflammatory and hyperalgesic mediator whose release is co-regulated by substance P. PATIENTS: Pancreatic tissue specimens obtained from 21 patients (16 male, five female) with chronic pancreatitis and 18 healthy organ donors (nine male, nine female) were analysed. METHODS: Gene expression of PPT-A and interleukin 8 was studied by northern blot analysis. Respective proteins were localised using immunohistochemistry. RESULTS: Northern blot analysis showed that PTT-A mRNA expression levels were present at comparable levels in normal and chronic pancreatitis tissue samples. In contrast, interleukin 8 mRNA was expressed at very low levels in normal controls but was increased 41-fold (p<0. 001) in chronic pancreatitis tissue samples. Using immunohistochemistry, interleukin 8 protein was localised mainly in immune cells often found around enlarged pancreatic nerves. In addition, in chronic pancreatitis, intense interleukin 8 immunostaining was present in metaplastic ductal cells of the atrophic pancreatic parenchyma. In chronic pancreatitis samples there was a positive relationship between interleukin 8 mRNA levels and the presence of ductal metaplasia (r=0.795; p<0.001) and the inflammation score (r=0.713; p<0.001). CONCLUSIONS: Our data indicate that in chronic pancreatitis, the increase in substance P in enlarged pancreatic nerves is not caused by enhanced intrapancreatic PTT-A mRNA expression, suggesting that the location of substance P synthesis is outside of the pancreas. In addition, localisation of interleukin 8 positive immune cells around pancreatic nerves further supports the existence of neuroimmune interactions as a pathophysiological mechanism in chronic pancreatitis.

Peripheral blood mononuclear cell production of interleukin-8 and IL-8-dependent neutrophil function in hypercholesterolemic patients.

Interleukin-8 is a cytokine produced by mononuclear cells that is involved in polymorphonuclear neutrophil leukocyte (PMN) recruitment and activation. Several studies have previously demonstrated a leukocyte activation during hypercholesterolemia and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have been found to play a role in the prevention of atherothrombotic disease. The purpose of this study was to determine interleukin-8 (IL-8) mRNA expression and ex vivo production from peripheral blood mononuclear cells (PBMCs) and IL-8-dependent PMN activation of hypercholesterolemic (HC) patients with respect to normocholesterolemic (NC) subjects. Using Northern blot analysis, we found a four- and threefold increase in the amount of IL-8 transcript in PBMC from HC patients, in unstimulated and LPS stimulated cultures, respectively. A specific immunoassay showed a correspondingly significant increase of IL-8 immunoactivity in the conditioned medium of PBMC from HC subjects as compared with controls (unstimulated PBMC: 15 +/- 4 vs. 4.2 +/- 3 ng/ml; P < 0.0001; LPS stimulated PBMC: 65.3 +/- 8 vs. 36.6 +/- 9 ng/ml; P < 0.0001). PMN of HC patients stimulated with IL-8 showed a reduced elastase release with respect to NC subjects before physiological granule release after f-Met-Leu-Phe (fMLP) treatment. These results indicate an upregulation of the IL-8 system in dyslipidemic patients and provide evidence for ongoing in vivo IL-8-dependent PMN activation during hypercholesterolemia.

Haemostatic abnormalities, cardiac involvement and serum tumor necrosis factor levels in X-linked dystrophic patients.

Left ventricular thrombosis and systemic emboli have been demonstrated to complicate cardiomyopathy in Duchenne and Becker muscular dystrophy (DMD, BMD). We investigated plasma levels of prothrombin fragment 1+2 (F1+2). thrombin-antithrombin III complex (TAT) and circulating levels of tumor necrosis factor-alpha (TNF-alpha), a procoagulant cytokine that has been shown to be elevated in patients with depressed cardiac function, in 20 patients with DMD and 12 patients with BMD as compared with 30 age-matched control subjects. Significantly elevated levels of F1+2 (DMD: 1.4+/-0.8 nmol/l; BMD: 1.8+/-0.8 nmol/l vs. controls: 0.7+/-0.2 nmol/l, p <0.01 and p <0.001, respectively), TAT complexes (DMD: 4.7+/-2.7 microg/l, BMD: 5+/-2.3 microg/l vs. controls: 1.6+/-0.5 microg/l, p <0.001) and TNF-alpha (54+/-9 vs. 25+/-7 pg/ml, p <0.001) were observed in patients with the dystrophic disease compared to control subjects. A significantly negative correlation was also found between F1+2 and TAT complexes and left ventricular ejection fraction (r = -0.65, p <0.0001; r = -0.80, p < 0.0001, respectively) and a positive correlation between F1+2 and TAT complexes and serum TNF-alpha levels (r = 0.67, p <0.0001; r = 0.70, p <0.0001, respectively). Our results indicate a hypercoagulable state in X-linked dystrophic patients. A possible relationship between haemostatic activation, left ventricular dysfunction and TNF-alpha system upregulation may be suggested.

Vascular non-protein thiols: prooxidants or antioxidants in atherogenesis?

Abstract-cell-mediated lipoprotein oxidation may be due to generation of non-protein thiols (NP-SH) from cystine with formation of oxidizing species. However, NP-SH, especially GSH, may also exert antioxidant effects in vitro and in vivo. To further investigate whether vascular NP-SH could be prooxidants or antioxidants in atherosclerosis, we have correlated the aortic content of NP-SH with that of lipoperoxides in 10 rabbits fed on a fat-enriched atherogenic diet for 9 weeks. As compared to 7 control rabbits, aortic NP-SH and lipoperoxides were significantly increased in the fat-fed animals. The levels of NP-SH were strongly and inversely correlated with those of lipid peroxidation in the atherosclerotic aorta (r(s) -0.92, P < 0.0001 for thiobarbituric acid reactive substances, and r(s) -0.80, P < 0.01 for fluorescent damage products of lipid peroxidation). A similar trend was evident also in the control rabbits (r(s) -0.60 for both indices of lipid peroxidation). Thus, the present data suggest that vascular NP-SH exert significant antioxidant-antilipoperoxidative effects in vivo especially in fat diet-related atherogenic conditions.

Antioxidant properties of ticlopidine on human low density lipoprotein oxidation.

We found that ticlopidine, at therapeutically relevant concentrations (2.5-10 microM), but not aspirin nor salicylate, significantly counteracted copper-driven human LDL oxidation. Ticlopidine, at 5 and 10 microM, was also antioxidant on peroxyl radical-induced LDL oxidation; yet it was ineffectual on thiol and ascorbate oxidation mediated by peroxyl radicals themselves, suggesting that drug antioxidant capacity is somehow related to the lipoprotein nature of the oxidizable substrate, but not to radical scavenging. The drug could not indeed react with the stable free radical 1,1-diphenyl-2-pycrylhydrazyl, nor had apparent metal complexing-inactivating activity. Thus, ticlopidine has antioxidant effects on LDL oxidation, which, together with its anti-platelet activity, could confer peculiar antiatherogenic properties to the drug in vivo.

Transforming growth factor beta1 induces IL-1 receptor antagonist production and gene expression in rat vascular smooth muscle cells.

Atherosclerosis is an inflammatory-fibroproliferative process that may represent a possible milieu in which transforming growth factor-beta (TGF-beta) can be involved. Vascular smooth muscle cells (VSMC) may represent a source or a target of a large number of growth factors and proinflammatory cytokines, including interleukin-1 and its receptor antagonist (IL-1Ra). We tested the effect of TGF-beta1, on IL-1Ra production and gene expression in rat VSMC cultures. We found a significant dose (3-30 ng/ml) and time-dependent (0-48 h) increase in IL-1Ra immunoactivity in the supernatant of conditioned medium and cell lysates. The maximal effect was observed with TGF-beta at 30 ng/ml and after 24 h incubation time, respect to untreated cells (320 +/- 26 vs. 211 +/- 20 pg/ml; P < 0.01). Furthermore, TGF-beta1 induced an increased mRNA expression which began at 2 h and peaked at 18 h incubation time (about a 6-fold increase with respect to unstimulated cells). The effect of TGF-beta1 on IL-1Ra production was completely inhibited by an anti-IL-1beta antibody (10 microg/ml) (from 320 +/- 81 to 181 +/- 46 pg/ml). These experiments suggest that TGF-beta1, potentially produced in the vascular wall during atherogenesis, may play a pathophysiological role in the autocrine control of IL-1 actions, via VSMC IL-1Ra production.

Increased transforming growth factor-beta production and gene expression by peripheral blood monocytes of hypertensive patients.

Cultured human peripheral blood monocytes are known to secrete and express transforming growth factor-beta (TGF-beta), a multifunctional cytokine that can be involved in myocardial and vascular remodeling. In addition, monocytes/macrophages have been demonstrated to be colocalized with fibrosis of hypertrophied heart and in the vascular wall of hypertensive vessels. In this study, we tested TGF-beta production and mRNA expression in peripheral blood monocytes from hypertensive patients with myocardial hypertrophy and increased carotid myointimal thickness with respect to healthy normotensive control subjects. We found an increased TGF-beta activity in the conditioned medium of monocytes from hypertensive patients compared with control subjects as evaluated by inhibition of [3H]thymidine incorporation by mink lung epithelial cells (-83% and -18% in hypertensive and normotensive subjects; P<.001). Western blot analysis confirmed a significant difference in the amount of TGF-beta protein secreted in the conditioned medium of hypertensive patients compared with that of normotensive subjects. Finally, we also observed a 4.2- and 5.5-fold increase in the amount of TGF-beta1 and TGF-beta2 transcripts, respectively. Our results indicate an upregulation of the TGF-beta system in the peripheral blood monocytes of hypertensive patients with cardiovascular structural changes, suggesting a possible role of TGF-beta monocyte production in hypertensive disease.

Infra-red laser irradiation enhances interleukin-1 receptor antagonist, increases 3H-thymidine incorporation and the release of [3H]arachidonic acid in human monocytes.

The effect of infra-red laser irradiation has been experimented on various biological systems and particularly in human tissues, in vitro as well as in vivo. In order to examine the influence of laser irradiation on cells of the monocytic lineage we have irradiated human peripheral blood mononuclear cells with an infra-red laser at a wavelength of 904 nm, at 2000 Hz frequency and 15 mW for 2 min. Here, we report that laser irradiation for 2 min. at different preincubation times (T = 0 and T = 30 min) enhances LPS (10 micrograms/ml or PHA (10 micrograms/ml, suboptimal concentration)-stimulated monocytes by modifying cell proliferation, as judged by [3H] thymidine incorporation. IL-1 receptor antagonist (IL-1ra) along with an increased release of [3H] Arachidonic acid production, is also influenced by laser irradiated monocytes when treated for 2 min after 1 h incubation. IL-1RA production increased 4-5 fold after laser irradiation, while 3H-arachidonic acid incorporated from PMA-stimulated cells increased and the effect was significant at T = 0 and T = 30 min; while at T = 1 h the effect was negligible. These results may provide new information regarding the effect of laser irradiation on the immune system.