Glioblastoma multiforme (GBM) is the most aggressive of the primary brain tumors, with a grim prognosis despite intensive treatment. In the past decades, progress in research has not significantly ...increased overall survival rate.
The in vitro antineoplastic effect and mechanism of action of Casiopeina III-ia (Cas III-ia), a copper compound, on rat malignant glioma C6 cells was investigated.
Cas III-ia significantly inhibited cell proliferation, inducing autophagy and apoptosis, which correlated with the formation of autophagic vacuoles, overexpression of LC3, Beclin 1, Atg 7, Bax and Bid proteins. A decrease was detected in the mitochondrial membrane potential and in the activity of caspase 3 and 8, together with the generation of intracellular reactive oxygen species (ROS) and increased activity of c-jun NH(2)-terminal kinase (JNK). The presence of 3-methyladenine (as selective autophagy inhibitor) increased the antineoplastic effect of Cas III-ia, while Z-VAD-FMK only showed partial protection from the antineoplastic effect induced by Cas III-ia, and ROS antioxidants (N-acetylcysteine) decreased apoptosis, autophagy and JNK activity. Moreover, the JNK -specific inhibitor SP600125 prevented Cas III-ia-induced cell death.
Our data suggest that Cas III-ia induces cell death by autophagy and apoptosis, in part due to the activation of ROS -dependent JNK signaling. These findings support further studies of Cas III-ia as candidate for treatment of human malignant glioma.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Considerable evidence implicates the proinflammatory cytokine CD40 ligand (CD40L) in atherosclerosis and accumulating data link type 1 and 2 diabetes, conditions associated with accelerated ...atherosclerosis, to inflammation. This study therefore evaluated the hypothesis that diabetic patients have elevated plasma levels of soluble CD40L (sCD40L) and that treatment with the insulin-sensitizing thiazolidinediones lowers this index of inflammation.
Subjects with type 1 (n=49) or type 2 diabetes (n=48) had higher (P<0.001) sCD40L plasma levels (6.56+/-3.27 and 6.67+/-2.90 ng/mL, respectively) compared with age-matched control groups (1.40+/-2.21 and 1.32+/-2.68 ng/mL, respectively). Multiple regression analysis demonstrated a significant (P<0.001) association between plasma sCD40L and type 1 as well as type 2 diabetes, independent of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, blood pressure, body mass index, gender, C-reactive protein, and soluble intracellular adhesion molecule-1. Furthermore, in a pilot study, administration of troglitazone (12 weeks, 600 mg/day), but not placebo, to type 2 diabetics (n=68) significantly (P<0.001) diminished sCD40L plasma levels by 29%. The thiazolidinedione lowered plasma sCD40L in type 2 diabetic patients with long-standing disease (>3 years) with or without macrovascular complications (-34% and -29%, respectively) as well as in type 2 diabetic patients with more recent (<3 years) onset of the disease (-27%; all P<0.05).
This study provides new evidence that individuals with type 1 or 2 diabetes have a proinflammatory state as indicated by elevated levels of plasma sCD40L. Troglitazone treatment of type 2 diabetic patients diminishes sCD40L levels, suggesting a novel antiinflammatory mechanism for limiting diabetes-associated arterial disease.
The purpose of this study is to investigate circulating endothelial progenitor cells (EPCs) and the signaling pathways involved in their recruitment in the ischemic retina of the 50/10 rat model of ...oxygen-induced retinopathy (OIR).
Within 12h after birth, litters of Sprague–Dawley rats and their mothers were exposed to alternating oxygen concentrations, followed by a room air exposition, to induce OIR. Retinopathy was quantified by ADPase stain in flat-mounted retinas and pre-ILM nuclei count in retinal sections. Semiquantitative real-time PCR and immunofluorescence were assessed in retinas to study stromal cell-derived factor 1 (SDF-1), its receptor CXCR4 and vascular endothelial growth factor (VEGF) expression. Circulating EPCs were evaluated by flow cytometry in peripheral blood.
Our results showed increased immunolabelling of SDF-1 in endothelial cells and strong expression of CXCR4 in Müller cells in OIR retinas as compared to control retinas. We found increased levels of CXCR4 and VEGF mRNA in OIR retinas, especially during the vascular attenuation stage. The number of circulating EPCs was decreased in OIR rats as compared to control rats.
The decrease in circulating EPCs could be implied in vessel growth arrest during normal retinal development in OIR rats, while pro-angionenic signals released by Müller cells in the hypoxic retina could drive pathological neovascularization in the ischemic retina. These data warrant further studies to investigate new therapeutic approaches for ROP.
BACKGROUNDCurrently there is no consensus regarding which add-on therapy to use in resistant hypertension. This study was designed to compare two treatment options, spironolactone (SPR) versus dual ...blockade of the renin–angiotensin–aldosterone system (RAAS).
METHODSForty-two patients with true resistant hypertension were included in the study. An open-label prospective crossover design was used to add a second RAAS blocker to previous treatment and then SPR following 1 month of wash-out. BP was measured in the office and by ambulatory blood pressure monitoring (ABPM). Changes in laboratory tests were also studied for both treatments. The predictive values of aldosterone–renin ratio (ARR) and serum potassium of determining the antihypertensive response were analyzed for both arms.
RESULTSFollowing the first stage of dual blockade, SBP dropped significantly both in office (reduction of 12.9 ± 19.2 mmHg)) and by ABPM (reduction of 7.1 ± 13.4 mmHg). Office DBP was unchanged but was significantly reduced as measured by ABPM (3.4 ± 6.2 mmHg). On SPR treatment, office BP was reduced 32.2 ± 20.6/10.9 ± 11.6 mmHg. By ABPM the reduction was 20.8 ± 14.6/8.8 ± 7.3 mmHg (P < 0.001). The BP control was achieved by 25.6% of patients in dual blockade and 53.8% in SPR with office blood pressure. By ABPM, 20.5% were controlled on dual blockade and up to 56.4% with SPR. Serum potassium was a weak inverse predictor of the blood pressure-lowering effect of SPR.
CONCLUSIONSPR has a greater antihypertensive effect than dual blockade of the RAAS in resistant hypertension. SPR at daily doses of 25–50 mg shows a potent antihypertensive effect when added to prior regimes of single RAAS axis blockade in patients with resistant arterial hypertension.
To evaluate the possible correlation between the visual field defects in patients with primary open-angle glaucoma (POAG) and the expression and enzymatic activity of nitric oxide synthase (NOS) ...isoenzymes and nitrotyrosine in trabecular meshwork (TM) samples.
TM specimens were collected from 146 patients with POAG by using standard filtration surgery. Visual field defects were evaluated by perimetry. Expression of endothelial (e)NOS and inducible (i)NOS were evaluated by quantitative RT-PCR. Constitutive (Ca2+-dependent) and iNOS (Ca2+-independent) activities were measured by the conversion of L-14C-arginine to L-14C-citrulline. In four TM specimens from POAG-affected eyes and in three human donor control eyes, 3-nitrotyrosine was localized by immunohistochemistry. The marker of lipid peroxidation malondialdehyde (MDA) was measured by the thiobarbituric acid test in samples of aqueous humor (AH) from 48 patients with either POAG or cataracts.
The results showed an upregulation of iNOS and a downregulation of calcium-dependent NOS correlated with visual field defects. Expression and activity of iNOS increased in parallel with visual field defects. However, constitutive activity decreased as the visual field defect increased. Nitrotyrosine was observed only in the cells of the TM specimens from eyes with severe POAG.
The increased expression and activity of iNOS in the TM of patients with POAG are proportional to the visual field defect and could lead to the increased of nitrotyrosine levels which may serve as marker of oxidative stress in the progression of cell death of the TM in POAG.
AIMS:The addition of an aldosterone receptor antagonist on top of current optimal therapy (based on angiotensin II inhibition) has demonstrated an important clinical benefit in heart failure patients ...with systolic dysfunction. Whether this finding also applies to heart failure patients with preserved systolic function is unknown. Therefore, we have studied the effect of adding eplerenone to standard pharmacological heart failure therapy (angiotensin-converting enzyme inhibitor/angiotensin receptor blocker and diuretic and β-blocker) in the progression of heart failure in spontaneously hypertensive heart failure (SHHF) rats.
METHODS AND RESULTS:Two-month-old SHHF rats were randomized to receive no treatment (SHHF group), a standard heart failure therapy (quinapril-torasemide-carvedilol; ST-SHHF group), or the combination of eplerenone and standard heart failure therapy (Eple+ST-SHHF group) for 20 months. Untreated SHHF was characterized by progressive left ventricular hypertrophy, fibrosis, and myocardial contractile and relaxation abnormalities, leading to pulmonary congestion. Despite similar blood pressure control, the addition of eplerenone to standard heart failure therapy further prevented left ventricular hypertrophy, contractile and relaxation alterations, and pulmonary congestion than standard heart failure therapy alone. ST-SHHF and Eple + ST-SHHF rats showed similar inhibition of structural extracellular matrix proteins collagen I, collagen III and fibronectin and metalloproteinase (MMP)-2, MMP-7, MMP-12, and MMP-13. However, only the coadministration of eplerenone with standard heart failure therapy normalized the expression of matricellular proteins thrombospondin 1, tenascin C, periostin, and secreted protein acidic rich in cysteine/osteonectin to values comparable to normotensive rats.
CONCLUSION:In a hypertensive heart failure rat model, the addition of eplerenone to conventional heart failure therapy further improves cardiac structural and functional parameters, delaying the progression of heart failure. These beneficial effects of eplerenone were associated with normalization of matricellular protein expression.
Ezetimibe, a selective inhibitor of intestinal cholesterol absorption, effectively reduces plasma cholesterol both in monotherapy or combined with a statin. However, its effect on atherosclerosis ...plaque progression is certainly unknown. MicroRNAs are short non-encoding RNA molecules dynamically implicated in monocytic differentiation which is considered an essential process during atherosclerosis development. The purpose of this study was to investigate the effect of ezetimibe on monocyte/macrophage differentiation as well as the implication of microRNAs (miRNAs) in this process. THP-1 differentiation with PMA became cells adherent to the plastic surface, and induced the expression of macrophage surface markers (CD11a, CD11b and ICAM-1) and miR-155, miR-222, miR-424 and miR-503. In the presence of ezetimibe, the adhesive capacity of THP-1 cells was decreased in a dose-dependent manner (P<0.05) and the expression of CD11a, CD11b and ICAM-1 was almost totally inhibited (P<0.05). The expression of miR-155, miR-222, miR-424 and miR-503 was reduced by 55%, 100%, 75% and 100%, respectively (P<0.05). Further mechanistic studies demonstrated that ezetimibe suppressed the PMA-induced phosphorylation of ERK/MAPK and inhibited the NF-κB activity, which are upstream signalling molecules in the differentiation process. In conclusion, ezetimibe inhibits PMA-induced THP-1 cell differentiation into macrophage-like cells in association with the inhibition of miRNA pathways. Our study suggests that inhibition of miRNAs might form a novel mechanism of anti-atherosclerotic effect of ezetimibe.
While the detection of subclinical atherosclerosis may provide an opportunity for the prevention of cardiovascular disease (CVD), which currently is a leading cause of death in HIV-infected subjects, ...its diagnosis is a clinical challenge. We aimed to compare the agreement and diagnostic performance of Framingham, SCORE and D:A:D equations for the recognition of subclinical atherosclerosis in HIV patients and to adjust the D:A:D equation using HIV and CVD variables.
Atherosclerosis was evaluated in 203 HIV-infected individuals by measuring the carotid intima-media thickness (IMT). The CVD risk was calculated using the Framingham, SCORE and D:A:D risk equations. Framingham, SCORE and D:A:D equations showed a low agreement with the IMT (Kappa: 0.219, 0.298, 0.244, respectively; p = 0.743) and a moderate predictive performance, (area under the curve AUC = 0.686, 0.665 and 0.716, respectively; p = 0.048), with the D:A:D equation being the most accurate. Atherosclerosis was demonstrated in a significant proportion of subjects with low predicted CVD risk by all three algorithms (16.3%, 17.2%, 17.2%, respectively; p = 0.743). In patients with an estimated low CVD risk atherosclerosis was associated with older age (p = 0.012) and low CD4 counts (p = 0.021). A model was developed to adjust the D:A:D equation; a significant increase in accuracy was obtained when CD4 counts and low-grade albuminuria were included (AUC = 0.772; p < 0.001).
The D:A:D equation overperforms Framingham and SCORE in HIV patients. However, all three equations underestimate the presence of subclinical atherosclerosis in this population. The accuracy of the D:A:D equation improves when CD4 counts and low-grade albuminuria are incorporated into the equation.
BACKGROUND:Although in the general population circulating vascular progenitor cell levels have been implicated in the homeostasis of the vascular wall through differentiation into endothelium and/or ...smooth muscle cells, it has not yet been assessed in HIV-infected patients. We herein investigated the number of progenitor cell subpopulations in HIV-infected patients and its relationship to carotid intima-media thickness (c-IMT).
METHODS:Blood samples were collected from 200 HIV-infected patients and CD34/KDR, CD34/VE-cadherin, and CD14/Endoglin progenitor cells were identified by flow cytometry. c-IMT was determined by ultrasonography. A group of 27 healthy subjects was used as control group.
RESULTS:In our population (20 ART-naive patients and 180 treated patients), traditional cardiovascular risk factors were not found predictive of vascular progenitor cell levels. However, antiretroviral therapy (ART)-treatment was identified as the main predictive value for low CD34/KDR cells and high CD14/Endoglin cells after adjustment by cardiovascular risk factors (age, sex, hypertension, diabetes, and hyperlipidaemia) and HIV-related characteristics (HIV duration and ART treatment). Low levels of circulating CD34/KDR or CD34/VE-cadherin endothelial progenitor cells tended to be associated with increased c-IMT. However, a positive association was found between CD14/Endoglin cells and c-IMT. Low number of CD34/KDR cells was also associated with the longest exposure to nucleoside reverse transcriptase inhibitors and/or protease inhibitors.
CONCLUSIONS:ART exposure is the main predictor of circulating vascular progenitor cell levels. However, their levels are only partially associated with high c-IMT in HIV-infected patients. ART has already been found to have proatherogenic effect, but our data first describe its relationship with vascular progenitor cells and c-IMT.
HIV-infected patients present increased incidence of cardiovascular disease (CVD). Although incipient kidney function impairment has been associated with CVD in the general population, this ...association has not been properly addressed in HIV-infected patients. We assessed the relationship between incipient renal impairment (IRI) and subclinical atherosclerosis in HIV-infected patients.
Estimated glomerular filtration rate (eGFR), carotid intima-media thickness (cIMT), and cardiovascular biomarkers were measured in 145 HIV-infected patients. IRI was defined as a composite variable: eGFR <90 mL/min, rate of eGFR decrease >3% annually over a period of 3 years, and albumin/creatinine urine ratio above the median (≥5 mg/g). Individuals with a cIMT ≥75th percentile or plaque were classified as having subclinical atherosclerosis.
Ninety-five patients (64.1%) met the criteria for IRI. As for HIV-related factors, patients with IRI more frequently had lipodystrophy (41.3% vs. 21.6%; P = 0.017), a lower CD4 lymphocyte nadir 210 (125-343) vs. 302 (178-408) cells/mL; P = 0.046, and longer exposure to nucleoside reverse transcriptase inhibitors 187 (84-259) vs. 104 (34-170) months; P = 0.001, to nonnucleoside reverse transcriptase inhibitors 32 (7-77) vs. 20 0-40) months; P = 0.043, and to protease inhibitors 42 (0-115 vs. 2.5 (0-59) months; P = 0.007. Patients with IRI more frequently had subclinical atherosclerosis (40.7% vs. 13.7%; odds ratio: 4.3; 95% confidence interval: 1.8 to 10.6; P = 0.001), even after adjustment for cardiovascular and HIV-related parameters (odds ratio: 3.8; 95% confidence interval: 1.3 to 11; P = 0.012).
The presence of IRI is an independent predictor of increased cIMT in HIV-infected patients and may help to identify patients with subclinical atherosclerosis and, therefore, increased risk of CVD.
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