Inhibition of SIRT1 deacetylase and p53 activation uncouples the anti-inflammatory and chemopreventive actions of NSAIDs.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been proposed as chemopreventive agents for many tumours; however, the mechanism responsible for their anti-neoplastic activity remains elusive and the side effects due to cyclooxygenase (COX) inhibition prevent this clinical application. METHODS: Molecular biology, in silico, cellular and in vivo tools, including innovative in vivo imaging and classical biochemical assays, were applied to identify and characterise the COX-independent anti-cancer mechanism of NSAIDs. RESULTS: Here, we show that tumour-protective functions of NSAIDs and exisulind (a sulindac metabolite lacking anti-inflammatory activity) occur through a COX-independent mechanism. We demonstrate these NSAIDs counteract carcinogen-induced proliferation by inhibiting the sirtuin 1 (SIRT1) deacetylase activity, augmenting acetylation and activity of the tumour suppressor p53 and increasing the expression of the antiproliferative gene p21. These properties are shared by all NSAIDs except for ketoprofen lacking anti-cancer properties. The clinical interest of the mechanism identified is underlined by our finding that p53 is activated in mastectomy patients undergoing intraoperative ketorolac, a treatment associated with decreased relapse risk and increased survival. CONCLUSION: Our study, for the first-time, links NSAID chemopreventive activity with direct SIRT1 inhibition and activation of the p53/p21 anti-oncogenic pathway, suggesting a novel strategy for the design of tumour-protective drugs.

Colorectal cancer patient-derived organoids and cell lines harboring ATRX and/or DAXX mutations lack Alternative Lengthening of Telomeres (ALT).

Telomere maintenance is necessary to maintain cancer cell unlimited viability. However, the mechanisms maintaining telomere length in colorectal cancer (CRC) have not been extensively investigated. Telomere maintenance mechanisms (TMM) include the re-expression of telomerase or alternative lengthening of telomeres (ALT). ALT is genetically associated with somatic alterations in alpha-thalassemia/mental retardation X-linked (ATRX) and death domain-associated protein (DAXX) genes. Cells displaying ALT present distinctive features including C-circles made of telomeric DNA, long and heterogenous telomeric tracts, and telomeric DNA co-localized with promyelocytic leukemia (PML) bodies forming so-called ALT-associated PML bodies (APBs). Here, we identified mutations in ATRX and/or DAXX genes in an extensive collection of CRC samples including 119 patient-derived organoids (PDOs) and 232 established CRC cell lines. C-circles measured in CRC PDOs and cell lines showed low levels overall. We also observed that CRC PDOs and cell lines did not display a significant accumulation of APBs or long telomeres with no appreciable differences between wild-type and mutated ATRX/DAXX samples. Overall, our extensive analyses indicate that CRC is not prone to engage ALT, even when carrying genetic lesions in ATRX and/or DAXX, and support the notion that ATRX/DAXX genomic footprints are not reliable predictors of ALT.

TGS1 mediates 2,2,7-trimethyl guanosine capping of the human telomerase RNA to direct telomerase dependent telomere maintenance.

Pathways that direct the selection of the telomerase-dependent or recombination-based, alternative lengthening of telomere (ALT) maintenance pathway in cancer cells are poorly understood. Using human lung cancer cells and tumor organoids we show that formation of the 2,2,7-trimethylguanosine (TMG) cap structure at the human telomerase RNA 5' end by the Trimethylguanosine Synthase 1 (TGS1) is central for recruiting telomerase to telomeres and engaging Cajal bodies in telomere maintenance. TGS1 depletion or inhibition by the natural nucleoside sinefungin impairs telomerase recruitment to telomeres leading to Exonuclease 1 mediated generation of telomere 3' end protrusions that engage in RAD51-dependent, homology directed recombination and the activation of key features of the ALT pathway. This indicates a critical role for 2,2,7-TMG capping of the RNA component of human telomerase (hTR) in enforcing telomerase-dependent telomere maintenance to restrict the formation of telomeric substrates conductive to ALT. Our work introduces a targetable pathway of telomere maintenance that holds relevance for telomere-related diseases such as cancer and aging.

Cancer-derived EVs show tropism for tissues at early stage of neoplastic transformation.

From the past decade, extracellular vesicles (EVs) have attracted considerable attention as tools for the selective delivery of anti-neoplastic drugs to cancer tissues. Compared to other nanoparticles, EVs display interesting unique features including immune compatibility, low toxicity and the ability to encapsulate a large variety of small- and macro-molecules. However, in virtually all studies, investigations on EVs have been focused on fully transformed cancers: the possibility to apply EV technology also to early-stage tumors has never been explored. Methods: Herein, we studied the ability of cancer-derived EVs to recognize and deliver their cargo also to incipient cancers. To this purpose, EV biodistribution was studied in MMTV-NeuT genetically modified mice during early mammary transformation, in fully developed breast tumors and in the normal gland of wild type syngeneic mice. EVs were loaded with indocyanine green (ICG), a near-infrared (NIR) dye together with oncolytic viruses and i.v. injected in mice. The nanoparticle biodistribution was assayed by in vivo and ex vivo optical imaging (detecting the ICG) and semiquantitative real-time PCR (measuring the adenoviral genome) in different tissues. Results: Our results demonstrate the ability of cancer-derived EVs to recognize early-stage neoplastic tissues opening the possibility to selectively deliver theranostics also for tumor prevention. Conclusions: Taken together our study demonstrates the ability of EVs to recognize and deliver diagnostic and therapeutic agents not only to fully transformed tissues but also to early stage tumors. These findings pave the way for the synthesis of "universal" EVs-based formulation for targeted cancer therapy.

Abnormal right ventricular mechanics in early systemic hypertension: a two-dimensional strain imaging study.

AIMS: To analyse the relationship between increasing systemic blood pressure (BP) and right ventricular (RV) function as assessed by two-dimensional strain imaging. METHODS AND RESULTS: Longitudinal peak strain and strain rate (SR) were sampled by speckle-tracking methodology at the RV free wall and interventricular septum (IVS) and RV and left ventricular (LV) structure and function were evaluated by conventional echo-Doppler sonography in 89 never-treated, non-obese subjects with office BP values varying from the optimal to mildly hypertensive range. Data were analysed by 24 h systolic BP (SBP) tertiles (cut-offs: 117 and 130 mmHg, n = 29, 30, and 30, respectively), thus partitioning subjects with optimal BP from those with high-normal and mildly increased values. RV peak systolic strain and early diastolic SR decreased in the mid-BP third without further changes in the upper tertile. IVS thickened gradedly by increasing systemic 24 h SBP; posterior wall remodelled to a lesser extent and poorly related to BP load and LV mass index did not change. RV and IVS systolic and diastolic strain indices associated inversely with increasing septal thickness. Conventional right and left indices of global ventricular function, left atrial size, and estimated systolic pulmonary pressure did not differ. CONCLUSION: Two-dimensional strain-assessed RV function is sensitive to increased systemic BP, even at levels below the conventional diagnostic limits for arterial hypertension. Subclinical RV systolic and diastolic abnormalities paralleled BP-driven septal remodelling, perhaps as a reflection of the crucial role played by IVS in RV function.

Lack of association between TGF-beta-1 genotypes and microalbuminuria in essential hypertensive men.

BACKGROUND: Polymorphisms within the gene for transforming growth factor (TGF)-beta-1, a pro-fibrogenic cytokine pathophysiologically involved in hypertension and hypertensive target damage, might modulate the biological activity of the encoded protein. Through that mechanism, they might contribute to microalbuminuria, a marker of subclinical renal damage and a correlate of systemic inflammation and endothelial dysfunction in hypertension, a possibility never before tested. For this reason, we assessed the association of four TGF-beta-1 polymorphic variants (C-509T, Leu(10)-->Pro, Arg(25)-->Pro, Thr(263)-->Ile) with albuminuria in uncomplicated essential hypertensive men, using (circulating active + acid-activatable latent) TGF-beta-1 levels as an indirect index of their in vivo biological activity. Because of the close pathophysiological link of TGF-beta-1 with the renin-angiotensin system, we also tested the behaviour of the angiotensin converting enzyme (ACE) deletion/insertion (D/I) polymorphism. METHODS: Albuminuria (three overnight collections), office and 24-h BP, left ventricular mass index (LVMI), BMI, renal function, glucose, lipids, plasma TGF-beta-1 (n = 162, ELISA) were measured in 222 genetically unrelated, never-treated, uncomplicated Caucasian hypertensive men. ACE D/I polymorphisms were analysed by the polymerase chain reaction technique or a 5' nuclease assay with further restriction analysis when required. RESULTS: Urine albumin levels or microalbuminuria (albuminuria > or =15 microg/min) did not differ by TGF-beta-1 genotypes, but both parameters were more frequent in ACE D/D homozygotes. Plasma TGF-beta-1 was similar across genetic backgrounds and was unrelated to albuminuria. Cardiovascular, renal, metabolic parameters were homogeneously distributed across genotypes. CONCLUSIONS: In contrast to its link with the ACE D/I genotype, microalbuminuria was independent of TGF-beta-1 polymorphism in this group of never-treated, uncomplicated essential hypertensive men.

Resistant hypertension: an overview.

Despite the availability of anti-hypertensive medications with proven efficacy and good tolerability, many hypertensive patients have blood pressure (BP) levels not at the goals set by international societies. Some of these patients are either non-adherent to the prescribed drugs or not optimally treated. However, a proportion has resistant hypertension (RH) defined as office BP above goal despite the use of ≥3 antihypertensive medications at maximally tolerated doses (one ideally being a diuretic). Diagnosis of RH based upon office measurements, however, needs confirmation through 24-h BP monitoring to exclude "white coat" RH since cardiovascular events and mortality rates follow mean ambulatory BPs. Standardized combination therapy based upon angiotensin converting enzyme inhibitors or angiotensin receptor blockers, amlodipine or other dihydropiridine calcium channel blockers and thiazide or thiazide-like diuretics has been advocated to treat RH with spironolactone as preferred fourth add-on drug. Interventional procedures such as renal denervation have been devised to treat RH and tested with insofar not positive results in series of patients not responding to medical treatment. It is unclear whether RH constitutes a specific phenotype of EH or should rather be considered a more serious form of uncontrolled hypertension. Whatever the case, its presence associates with an increased cardio- and cerebrovascular risk and deserves, therefore, particular care.

Lack of association between endothelial nitric oxide synthase gene polymorphisms, microalbuminuria and endothelial dysfunction in hypertensive men.

BACKGROUND: The Glu298Asp, T786C and 4a/4b genetic polymorphisms within the endothelial nitric oxide synthase (e-NOS) gene may predispose to hypertension, ischaemic heart disease and renal damage, possibly by reducing the generation of nitric oxide (NO), a fundamental substance in renal and cardiovascular biology. That same mechanism may contribute to raise albuminuria, a correlate of endothelial dysfunction and a marker of early kidney damage and poor cardiovascular prognosis in patients with hypertension. To assess that hypothesis, we evaluated the association of albuminuria with eNOS genotypes and their interacting potential with the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism. We also tested their impact on systemic NO availability, as reflected by endothelial-mediated forearm vasodilatation. METHODS: Albuminuria (three overnight collections), blood pressure, body mass index, renal function, glucose, lipids and prevalence of the metabolic syndrome were measured in 235 genetically unrelated, never-treated, uncomplicated white men with essential hypertension. Endothelial function was assessed in a patient subgroup (n = 94) by measuring plethysmographic forearm blood flow vasodilatation in response to intra-arterial acetylcholine with sodium nitroprusside as a control. Polymerase chain reaction or a 5' nuclease assay were used to characterize the eNOS and ACE I/D variants. RESULTS: Albuminuria or microalbuminuria (albuminuria > or = 15 microg/min) showed no association with eNOS polymorphisms either per se or after accounting for the co-existing ACE I/D genetic configuration. Forearm responses to acetylcholine did not differ by eNOS polymorphisms. Cardiovascular, renal, metabolic parameters were homogeneously distributed across different genetic backgrounds. CONCLUSION: eNOS polymorphisms apparently play no role in promoting hypertensive renal damage, and do not influence endothelial-mediated vasodilatation in never-treated men with essential hypertension.

Association between plasma gamma-glutamyltransferase fractions and metabolic syndrome among hypertensive patients.

Among the risk factors associated to metabolic syndrome (MetS), hypertension shows the highest prevalence in Italy. We investigated the relationship between the newly identified serum γ-glutamyltransferase (GGT) fractions, b- s- m- f-GGT, and risk factors associated to MetS in hypertensive patients. A total of ninety-five consecutive hypertensive patients were enrolled. GGT fractions were analysed by gel-filtration chromatography, and hepatic steatosis was evaluated by ultrasound. MetS was diagnosed in 36% of patients. Considering the whole group, b- and f-GGT showed the highest positive correlation with BMI, glucose, triglycerides and insulin, and the highest negative correlation with HDL cholesterol. While both serum triglycerides and insulin were independently associated with b-GGT levels, only triglycerides were independently associated with f-GGT. The values of b-GGT activity increased with steatosis grade (g0 = 1.19; g2 = 3.29; ratio g2/g0 = 2.75, p < 0.0001 linear trend). Patients with MetS showed higher levels of b-GGT, m-GGT and f-GGT [median (25th-75th) U/L: 3.19 (1.50-6.59); 0.55 (0.26-0.81); 10.3 (9.1-13.6); respectively] as compared to subjects presenting with one or two MetS criteria [1.75 (0.95-2.85), p < 0.001; 0.33 (0.19-0.60), p < 0.05; 8.8 (7.0-10.6), p < 0.001]. Our data point to a potential role for b- and f-GGT fractions in identifying MetS patients among hypertensive subjects, thus providing a minimally invasive blood-based tool for MetS diagnosis.

The laminA/NF-Y protein complex reveals an unknown transcriptional mechanism on cell proliferation.

Lamin A is a component of the nuclear matrix that also controls proliferation by largely unknown mechanisms. NF-Y is a ubiquitous protein involved in cell proliferation composed of three subunits (-YA -YB -YC) all required for the DNA binding and transactivation activity. To get clues on new NF-Y partner(s) we performed a mass spectrometry screening of proteins that co-precipitate with the regulatory subunit of the complex, NF-YA. By this screening we identified lamin A as a novel putative NF-Y interactor. Co-immunoprecipitation experiments and confocal analysis confirmed the interaction between the two endogenous proteins. Interestingly, this association occurs on euchromatin regions, too. ChIP experiments demonstrate lamin A enrichment in several promoter regions of cell cycle related genes in a NF-Y dependent manner. Gain and loss of function experiments reveal that lamin A counteracts NF-Y transcriptional activity. Taking advantage of a recently generated transgenic reporter mouse, called MITO-Luc, in which an NF-Y-dependent promoter controls luciferase expression, we demonstrate that lamin A counteracts NF-Y transcriptional activity not only in culture cells but also in living animals. Altogether, our data demonstrate the occurrence of lamin A/NF-Y interaction and suggest a possible role of this protein complex in regulation of NF-Y function in cell proliferation.

Alpha-adducin and angiotensin-converting enzyme polymorphisms in hypertension: evidence for a joint influence on albuminuria.

BACKGROUND: A single-nucleotide polymorphism (Gly460Trp) within the alpha-adducin gene (ADD1) may influence several renal phenotypes, including salt sensitivity, susceptibility to renal failure, the renal haemodynamics and confer a worse cardiovascular risks profile. However, its relationship with microalbuminuria, a marker of early renal and cardiovascular damage and an independent predictor of morbid events in hypertension, is unknown. For this reason, we related the ADD1 genetic polymorphism to urine albumin levels and other clinical variables in essential hypertensive men. The angiotensin-converting enzyme (ACE) insertion/deletion (ID) polymorphism was also evaluated because of its interactive potential with the ADD1 genotype. METHODS: Albuminuria (three overnight collections), echocardiographic left ventricular mass index, blood pressure, body mass index, renal function, glucose and lipids were measured in 238 genetically unrelated, never treated, uncomplicated Caucasian essential hypertensive men. Polymerase chain reaction or a 5' nuclease assay were used to characterize the ACE ID and ADD1 Gly460Trp variants, respectively. RESULTS: Microalbuminuria (albuminuria >or= 15 microg/min) was more frequent in patients with the ACE DD variant, but only in those with a ADD1 Gly460Gly background. In contrast, urine albumin did not differ by ACE ID genotype in the presence of mutated ADD1 Trp alleles. ADD1 polymorphisms per se were not associated with albuminuria. Cardiovascular, renal, metabolic parameters were homogeneously distributed among different genetic backgrounds. CONCLUSIONS: ACE DD and ADD1 Gly460Gly polymorphisms may jointly influence albuminuria in hypertensive men, 460Gly homozygosis facilitating or, possibly, the 460Trp allele mitigating the noxious renal impact of the ACE DD genotype. The data highlight further the complex pathophysiological implications of microalbuminuria in hypertension.

ACE gene insertion/deletion polymorphism modulates capillary permeability in hypertension.

A D/D (deletion/deletion) polymorphism within the ACE (angiotensin 1-converting enzyme) gene increases the risk of microalbuminuria, a predictor of atherosclerotic vascular disease, in essential hypertension. It is unknown, however, whether this genetic profile is accompanied by disturbed macromolecular permeability of systemic capillary endothelium, possibly in the context of generalized endothelial dysfunction. In the present study, the ACE gene polymorphism was determined by PCR in 79 never-treated uncomplicated hypertensive men and 16 normotensive men as controls. Evaluation variables were TERalb (transcapillary escape rate of albumin; the 1-h decline rate of intravenous (125)I-albumin, a measure of integrity of systemic capillary endothelium), albuminuria and forearm vasodilation to intra-arterial acetylcholine, an index of NO (nitric oxide)-mediated vasomotion, in addition to a series of sensitive parameters of albumin permeation (blood pressure, metabolic status and smoking habits). Analyses were done by comparing D/D homozygotes with grouped I/D (insertion/deletion) and I/I (insertion/insertion) subjects. TERalb was higher in D/D hypertensives, who had higher albuminuria, more frequent microalbuminuria and comparable forearm responsiveness to intra-arterial acetylcholine. Fasting glucose and insulin, insulin sensitivity, 24-h blood pressure, smoking habits and metabolic parameters did not differ between the two groups. TERalb and urine albumin values were positively associated in the hypertensive subjects. In conclusion, ACE D/D homozygosis, independently of several confounding factors, associates with higher TERalb in men with essential hypertension. This may reflect noxious genetic influences on systemic vascular permeability, a critical control mechanism for atherogenesis in the absence of grossly impaired NO-mediated arteriolar responsiveness. The parallel behaviour of TERalb and albuminuria suggests some shared genetically mediated determinant of renal and systemic microvascular abnormalities in hypertension.

Bioluminescence imaging of estrogen receptor activity during breast cancer progression.

Estrogen receptors (ER) are known to play an important regulatory role in mammary gland development as well as in its neoplastic transformation. Although several studies highlighted the contribution of ER signaling in the breast transformation, little is known about the dynamics of ER state of activity during carcinogenesis due to the lack of appropriate models for measuring the extent of receptor signaling in time, in the same animal. To this aim, we have developed a reporter mouse model for the non-invasive in vivo imaging of ER activity: the ERE-Luc reporter mouse. ERE-Luc is a transgenic mouse generated with a firefly luciferase (Luc) reporter gene driven by a minimal promoter containing an estrogen responsive element (ERE). This model allows to measure receptor signaling in longitudinal studies by bioluminescence imaging (BLI). Here, we have induced sporadic mammary cancers by treating systemically ERE-Luc reporter mice with DMBA (9,10-dimethyl 1,2-benzanthracene) and measured receptor signaling by in vivo imaging in individual animals from early stage until a clinically palpable tumor appeared in the mouse breast. We showed that DMBA administration induces an increase of bioluminescence in the whole abdominal area 6 h after treatment, the signal rapidly disappears. Several weeks later, strong bioluminescence is observed in the area corresponding to the mammary glands. In vivo and ex vivo imaging analysis demonstrated that this bioluminescent signal is localized in the breast area undergoing neoplastic transformation. We conclude that this non-invasive assay is a novel relevant tool to identify the activation of the ER signaling prior the morphological detection of the neoplastic transformation.

Incremental value of ultrasonic tissue characterization (backscatter) in the evaluation of left ventricular myocardial structure and mechanics in essential arterial hypertension.

BACKGROUND: Ultrasonic backscatter parameters were analyzed in hypertensive patients and divided into groups according to both severity of left ventricular hypertrophy (LVH) (group A: no LVH [n=52]; B: mild to moderate LVH [n=55]; and C: severe LVH [n=10]) and left ventricular geometry (normal geometry [n=44]; concentric remodeling [n=8]; concentric hypertrophy [n=25]; and eccentric hypertrophy [n=40]). METHODS AND RESULTS: We studied 117 male, essential hypertensive patients and 19 normotensive, age-matched (40+/-5 years), healthy subjects who served as controls. Ambulatory and office blood pressure measurements were taken and 2-dimensional Doppler echocardiography and ultrasonic myocardial integrated backscatter (IBS) were performed. A group from the hypertensive study population (n=16) was observed after a period of pharmacological antihypertensive treatment to determine the behavior of backscatter parameters in relation to eventual regression of left ventricular mass (LVM). The cyclic variation index (CVIs) of the backscatter signal at the septum level was grouped according to each LVM level and was 29.4+/-9.3 (controls), 15+/-11 (group A), 9.5+/-10 (group B), and -1.5+/-8.6 (group C) (P<0.001). CVI septum values grouped according to left ventricular geometry were 15+/-11 (normal geometry), 12+/-7 (concentric remodeling), 7+/-11 (concentric hypertrophy), and 7.8+/-11 (eccentric hypertrophy) (P<0.01). Follow-up data demonstrate a significant reduction of LVM after therapy, as well as a significant increase in CVIs toward normal values. CONCLUSIONS: Hypertensive patients with higher LVM had the worst prognosis; in fact, those patients had the most significant CVI alterations. Regression of LVM subsequent to chronic pharmacological therapy induces a normalization of ultrasonic backscatter parameters. Ultrasonic tissue characterization (backscatter) analysis could allow early identification of patients at risk of developing complications of hypertensive cardiopathy.

LDL cholesterol and global risk stratification in referred hypertensive patients.

BACKGROUND: Global risk status more than BP values per se drive nowadays treatment decisions and increasing emphasis is given to the role of lipid control in hypertension (HT). However, the distribution of circulating low density lipoproteins (LDL) levels as a function of risk profile and lipid-lowering treatment in hypertensive patients is unclear. METHODS: We analysed 1196 patients (677 males, age range: 20-80 years) referred to our Hypertension Unit with treatment history and a complete dataset (systolic blood pressure levels, being on anti-hypertensive treatment or not, total and high density lipoproteins (HDL) cholesterol, smoking status, sex, age) for 10-year absolute coronary heart disease (CHD) risk stratification by National Cholesterol Education Program (NCEP)/ATP III guidelines. LDL cholesterol <25.9 mmol/L (100 mg/dL) was the target for high-risk patients (vascular diseases, diabetes, hypertension with multiple risk factors at CHD risk >20%/10 years). LDL <33.6 mmol/L (130 mg/dL) and 41.4 mmol/L (160 mg/dL) were the thresholds for intermediate (10-20%/10 years) and low (<10%/10 years) CHD risk. RESULTS: At referral, 78% of high-risk patients were above target LDL and, overall, 56% had LDL cholesterol above the desired risk-specific thresholds. Lipid-lowering treatment was prescribed in 19% in whom LDL was actually higher than the untreated group. CONCLUSIONS: LDL cholesterol was out of target in most of a large series of referred high-risk hypertensive patients and LDL levels were largely unsatisfactory even in those undergoing lipid-lowering treatment. The data show the intensive effort still needed to implement global risk-oriented prevention strategies in hypertensive populations.

Insulin resistance causes impaired vasodilation and hypofibrinolysis in young women with polycystic ovary syndrome.

INTRODUCTION: Insulin resistance, a novel cardiovascular risk factor, is often associated with increased plasminogen activator inhibitor-1 levels and impaired vasodilation. Insulin infusion in the forearm induces plasminogen activator inhibitor-1 and tissue plasminogen activator expression and endothelium-dependent vasodilation in normal subjects. The present study explores the relationship between insulin-induced vasodilatory and fibrinolytic properties of the endothelium in women with polycystic ovary syndrome, frequently affected by insulin resistance and early atherosclerosis. MATERIALS AND METHODS: Metabolic, hormonal and fibrinolytic parameters were evaluated in 64 patients with polycystic ovary syndrome (19 insulin-resistant and 45 insulin-sensitive) and in 25 controls. In 16 women with polycystic ovary syndrome, 8 insulin-resistant and 8 insulin-sensitive, blood flow, plasminogen activator inhibitor-1 and tissue plasminogen activator expression were evaluated during insulin infusion into the forearm. RESULTS: Elevated basal plasminogen activator inhibitor-1 levels were found in women with polycystic ovary syndrome, correlating directly with insulin levels. Plasminogen activator inhibitor-1 expression increased during insulin infusion in all women with polycystic ovary syndrome, but was delayed and sustained in insulin-resistant patients (p<0.01). Vasodilatory response to insulin was blunted (p<0.01) and tissue plasminogen activator expression abolished in insulin-resistant patients (p<0.01). CONCLUSION: Our study demonstrates that women with polycystic ovary syndrome and insulin resistance show a blunted endothelial-dependent vasodilation. The impaired endothelial release of tissue-plasminogen activator and the sustained plasminogen activator inhibitor-1 release during insulin infusion suggest a hypofibrinolytic state in PCOS patients with insulin resistance. This hemodynamic and fibrinolytic derangement may contribute to the pathogenesis of early atherosclerosis in insulin resistance.

Low-grade inflammation and microalbuminuria in hypertension.

UNLABELLED: Background- Albuminuria and C-reactive protein (CRP), a marker of systemic low-grade inflammation, are frequently elevated in essential hypertension and predict cardiovascular prognosis independent of conventional risk factors. However, in spite of their potentially important links, the interrelationships between the 2 parameters have not been explored in depth in hypertensive patients. METHODS AND RESULTS: Albuminuria (the mean of 3 overnight urine collections), high-sensitive CRP (hs-CRP), 24-hour blood pressure (BP), weight, lipids, poststimulative (75 g PO) plasma glucose, insulin, and insulin sensitivity by the homeostasis model assessment model were evaluated in 220 never treated, nondiabetic, uncomplicated essential hypertensive men. Albuminuria > or =15 microg/min was defined as microalbuminuria and hs-CRP values above and below median (2.3 mg/L) as high and low, respectively. Concentric left ventricular hypertrophy was diagnosed by echocardiography, and a full-blown metabolic syndrome was identified in presence of hypertension and at least 3 of following: obesity, subclinical hyperglycemia, low high-density lipoprotein (HDL) and high triglycerides. Microalbuminuria was present in 54 patients, 29 with high hs-CRP characterized by higher 24-hour systolic BP, postload glucose, body mass index, lower HDL cholesterol, more frequent metabolic syndrome, concentric LVH, and active smoking than those with either isolated microalbuminuria (n=27) or normoalbuminuria. CONCLUSIONS: Microalbuminuria accompanied by evidence of subclinical inflammation is a strong correlate of metabolic abnormalities in essential hypertension and identifies a patient subset at very high cardiovascular risk. In contrast, isolated microalbuminuria may represent a distinct pathophysiological condition characterized by a more benign profile and possibly a better prognosis.

The vascular effects of doxazosin in hypertension complicated by metabolic syndrome.

AIMS: To evaluate the vascular effects of doxazosin, an alpha-1 antagonist, in hypertensive patients with metabolic syndrome in whom the drug has previously been shown to exert beneficial metabolic actions on lipids and insulin metabolism. EXPERIMENTAL PROTOCOL: Twelve untreated non-diabetic hypertensive patients with National Cholesterol Education Program (NCEP) ATP-III defined metabolic syndrome were assigned to three-months of treatment with doxazosin (5.5 +/- 1.9 mg/die). Study variables were measured at baseline and after treatment. End-points: forearm blood flow (strain-gauge plethysmography) responses to graded intra-arterial acetylcholine and sodium nitroprusside infusion to test endothelium-dependent and independent vasodilatation respectively. Minimum forearm vascular resistance, the ratio of mean blood pressure and post-ischaemic maximal blood flow, as an index of arteriolar structure; transcapillary albumin escape rate (the 1-h decay rate of I-albumin, 6-8 microC ev) as a measure of systemic capillary permeability. Lipids, fasting and post-glucose insulin were measured at baseline and after treatment. RESULTS: Doxazosin reduced blood pressure, augmented acetylcholine-mediated vasodilatation, decreased minimum resistance and, although not to a statistically significant extent, transvascular albumin leakage increased high-density lipoprotein (HDL) cholesterol while triglycerides and post-stimulative hyperinsulinemia decreased. CONCLUSIONS: Doxazosin improved endothelial-mediated vasomotor function and reversed abnormal arteriolar structure in hypertensive patients with metabolic syndrome while improving lipid profile and blunting post-glucose hyperinsulinemia.

Chlorthalidone improves endothelial-mediated vascular responses in hypertension complicated by nondiabetic metabolic syndrome.

BACKGROUND: The study was conducted to evaluate the vascular effects of chlorthalidone, a distal tubule-acting natriuretic agent, in hypertensive patients with nondiabetic metabolic syndrome, an insulin-resistant condition characterized by endothelial dysfunction and high risk for diabetes mellitus development. METHODS: Thirteen untreated hypertensive patients with Adult Treatment Panel-III-defined nondiabetic metabolic syndrome were assigned to 3-month treatment with chlorthalidone. The end-points were baseline and post-treatment evaluation of (1) forearm blood flow (strain-gauge plethysmography) responses to graded intra-arterial acetylcholine infusion to test endothelial-mediated vasomotor function, with sodium nitroprusside as a control for endothelium-independent vasodilatation; (2) minimum forearm vascular resistance, the ratio of mean blood pressure and maximal blood flow in response to 13-minute arterial occlusion, as a hemodynamic correlate of arteriolar structure; and (3) transcapillary albumin escape rate (the 1-hour decay rate of (125)I-albumin, 6-8 microC ev) as a measure of systemic capillary permeability. Additional measurements included baseline and posttreatment lipids, fasting, and postload glucose and insulin as well as the homeostasis model assessment, an index of insulin sensitivity. RESULTS: Chlorthalidone reduced blood pressure, augmented acetylcholine-mediated vasodilatation, decreased minimum forearm resistance, and slowed the transcapillary albumin escape rate. Metabolic parameters did not change significantly except for an increase in low-density lipoprotein cholesterol levels. CONCLUSIONS: Chlorthalidone improved endothelial function, reversed abnormal arteriolar structure, and slowed albumin permeation in hypertensive patients with nondiabetic metabolic syndrome.

Health care delivery in type 2 diabetes. A survey in an Italian primary care practice.

AIMS: Evidence-based guidelines provide targets and performance measures for the treatment of type 2 diabetic patients but a wide gap separates guidelines-driven recommendations from their clinical application, a phenomenon hindering the transfer of proven benefits to affected populations. METHODS: We analyzed the quality of diabetic care delivered by 8 general practitioners joint in a group practice attending 571 diabetic patients (5.6% of the total enlisted subjects) by assessing process (% of HbA1c, SBP and LDL-C determinations) and intermediate outcome (% of patients with HbA1c <7% vs >8%, systolic BP <130 mmHg vs >140 mmHg, LDL-cholesterol <100 mg/dL vs >130 mg/dL) indicators. RESULTS: HbA1c was at target in 49% of patients and >8% in 22%; SBP and LDL-C determination was available in about two-thirds of patients, only a minority at target for SBP and LDL-C. Antihyperglycemic and antihypertensive treatment was prescribed in most patients but only a third was on statins. During the post-evaluation phase, percentages of patients with HbA1c >8%, SBP < 130 mmHg and LDL-C < 100 mg/dL and the drug prescription pattern did not change. CONCLUSIONS: Several weaknesses affect primary care delivery to type 2 diabetic patients and efforts are needed to improve the management of this high-risk group.