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Renato Fellin

Publications and source records attributed to Renato Fellin.

30 records · Page 2Linked to original sources
PubMed2004

[Intestinal cholesterol absorption: a pharmacological target for lowering of plasma cholesterol].

A number of clinical studies clearly demonstrate the efficacy of hypocholesterolemic treatment in reducing incident cardiovascular events. The benefit appears to be proportional to the reduction of LDL cholesterol. Recent guidelines suggest an even more stringent target of 70 mg/dl for LDL cholesterol in high-risk subjects. Statins represent a very effective treatment of hypercholesterolemia, and the co-administration of drugs with complementary mechanisms of action, may represent an additional pharmacological tool in clinical practice to achieve the suggested targets for LDL lowering. In this short review we address the most recent discoveries in the physiological pathways of cholesterol absorption and identify the concept of dual inhibition as a therapeutic paradigm that may help in reaching the LDL cholesterol targets in clinical practice.

Cardiovascular Diseases↗
PubMed2003

Defective P2Y purinergic receptor function: A possible novel mechanism for impaired glucose transport.

Extracellular ATP is an ubiquitous mediator that regulates several cellular functions via specific P2 plasma membrane receptors (P2Rs), for which a role in modulating intracellular glucose metabolism has been recently suggested. We have investigated glucose uptake in response to P2Rs stimulation in fibroblasts from type 2 diabetic (T2D) patients and control subjects. P2Rs expression was evaluated by RT-PCR; intracellular calcium release by fluorometry; glucose transporter (GLUT1) translocation by immunoblotting and chemiluminescence; glucose uptake was measured with 2-deoxy-D-[1-(3)H]glucose (2-DOG) and ATP by luminometry. Cells from T2D patients, in contrast to those from healthy controls, showed no increase in glucose uptake after ATP stimulation; extracellular ATP caused, however, a similar GLUT1 recruitment to the plasma membrane in both groups. P2Rs expression did not differ between fibroblasts from diabetic and healthy subjects, but while plasma membrane depolarization, a P2X-mediated response was similar in both groups, no evident intracellular calcium increase was detectable in the cells from the former group. The calcium response in fibroblasts from diabetics was restored by co-incubation with apyrase or hexokinase, suggesting that P2YRs in those cells were normally expressed but chronically desensitised. In support to this finding, fibroblasts from T2D subjects secreted a two-fold larger amount of ATP compared to controls. Pre-treatment with apyrase or hexokinase also restored ATP stimulated glucose uptake in fibroblasts from diabetic subjects. These results suggest that extracellular ATP plays a role in the modulation of glucose transport via GLUT1, and that the P2Y-dependent GLUT1 activation is deficient in fibroblasts from T2D individuals. Our observations may point to additional therapeutic targets for improving glucose utilization in diabetes.

Adenosine Triphosphate↗
PubMed2003

Serum cholesterol levels and in-hospital mortality in the elderly.

PURPOSE: Although total cholesterol levels among middle-aged persons correlate with long-term mortality from all causes, this association remains controversial in older persons. We explored whether total cholesterol levels were independently associated with in-hospital mortality among elderly patients. METHODS: We analyzed data from a large collaborative observational study, the Italian Group of Pharmacoepidemiology in the Elderly (GIFA), which collected data on hospitalized patients. A total of 6984 patients aged 65 years or older who had been admitted to 81 participating medical centers during four survey periods (from 1993 to 1998) were enrolled. Patients were divided into four groups based on total cholesterol levels at hospital admission: <160 mg/dL (n = 2115), 160 to 199 mg/dL (n = 2210), 200 to 239 mg/dL (n = 1719), and >or=240 mg/dL (n = 940). RESULTS: Patients (mean [+/- SD] age, 78 +/- 7 years) were hospitalized for an average of 15 +/- 10 days. The mean total cholesterol level was 186 +/- 49 mg/dL. A total of 202 patients died during hospitalization. Mortality was inversely related to cholesterol levels (<160 mg/dL: 5.2% [110/2115]; 160-199 mg/dL: 2.2% [49/2210]; 200-239 mg/dL: 1.6% [27/1719]; and >or=240 mg/dL: 1.7% [16/940]; P for linear trend <0.001). After adjustment for potential confounders (demographic characteristics, smoking, alcohol use, indicators of nutritional status, markers of frailty, and comorbid conditions), low cholesterol levels continued to be associated with in-hospital mortality. Compared with patients who had cholesterol levels <160 mg/dL, the odds ratios for in-hospital mortality were 0.49 (95% confidence interval [CI]: 0.34 to 0.70) for participants with cholesterol levels of 160 to 199 mg/dL, 0.41 (95% CI: 0.26 to 0.65) for those with cholesterol levels of 200 to 239 mg/dL, and 0.56 (95% CI: 0.32 to 0.98) for those with cholesterol levels >or=240 mg/dL. These estimates were similar after further adjustment for inflammatory markers and after excluding patients with liver disease. CONCLUSIONS: Among older hospitalized adults, low serum cholesterol levels appear to be an independent predictor of short-term mortality.

Age Factors↗
PubMed2003

Effect of a standardized grape seed extract on low-density lipoprotein susceptibility to oxidation in heavy smokers.

The aim of our study was to evaluate the effect of a standardized formulation of a polyphenolic extract of grapes (Leucoselect-Phytosome [LP]) on low-density lipoprotein (LDL) susceptibility to oxidation in a group of heavy smokers. A randomized, double-blind, crossover study was undertaken in 24 healthy male heavy smokers, aged > or = 50 years. Enrolled subjects were given 2 capsules twice daily for 4 weeks (phase 1). Each capsule contained 75 mg of a grape procyanidin extracts and soy-phosphatidlcholine or placebo consisiting of 75 mg lactose and soy-phosphatidlcholine. A wash out period of 3 weeks was then followed by 4 weeks of the opposite treatment (phase 2). Blood samples were taken at baseline and at the end of each phase and assayed for plasma lipids and LDL susceptibility to oxidation. Compliance was good, and no adverse effects were recorded. Subjects did not show significant modification of total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C) and LDL-C during LP treatment. Among oxidative indices, thiobarbituric acid reactive substances (TBARS) concentration was significantly reduced in subjects taking LP (-14.7% +/- 21.1% v +5.0% +/- 18.1%, P <.01), and the lag phase prolonged (+15.4% +/- 24.4% v -0.1% +/- 16.0%, P <.05) compared with placebo and basal values. The antioxidant potential of grape seed extract polyphenols may prove effective in a model of oxidative stress (smoking); however more investigational data are needed before use in wider clinical settings.

Antioxidants↗
PubMed2003

Progression of lower-extremity disability in older women with diabetes: the Women's Health and Aging Study.

OBJECTIVE: Older patients with diabetes are more likely to have a higher prevalence of multiple risk factors for physical disability, as a result of diabetic complications. We evaluated the pace of decline in lower-extremity function and the risk for progression of disability in older women with diabetes. RESEARCH DESIGN AND METHODS: We conducted a 3-year longitudinal cohort study of a random sample of 729 physically impaired older women (age > or =65 years) living in the community (Baltimore, MD). Diabetes was ascertained by standard criteria. Self-reported functional status and objective performance measures were assessed at baseline and over six semiannual follow-up visits. RESULTS: The baseline prevalence of diabetes was 14.4%. After adjustment for age and compared with women without diabetes, those with diabetes had an RR of 1.8 (95% CI 1.3-2.5) for incident mobility disability and 1.6 (1.2-2.1) for incident activity of daily living disability. The increased incidence of new disability associated with diabetes was paralleled by a greater decline in objective measures of lower-extremity function. Adjustment for multiple risk factors for disability did not significantly attenuate the risk for disability associated with diabetes. CONCLUSIONS: In older patients, impaired lower-extremity function is a long-term diabetic complication. Comprehensive assessment of older diabetic patients should include a standardized evaluation of lower-extremity performance.

Activities of Daily Living↗
PubMed2003

[Dyslipidemia and global cardiovascular risk: treatment guidelines].

Epidemiological studies identified several risk factors as cardiovascular disease correlates, including smoking, obesity, hypertension, diabetes, and increased plasma lipids. High blood cholesterol, and in particular LDL cholesterol levels, represents a major determinant of coronary artery disease, in particular when included in the context of a comprehensive risk profile. The more recent guidelines (especially NCEP ATP III in the United States, and the European Joint Task Force) have suggested the opportunity to favor treatment of those subjects with higher global cardiovascular risk, first of all of those individuals with coronary artery disease or another cardiovascular manifestation or diabetes, then of subjects with clustered risk factors or with markedly raised levels of single risk factors, eventually of other subjects. In this perspective the treatment also of slight dyslipidemias has been shown capable of reducing cardiovascular event incidence and mortality. Recent investigations, aiming at evaluating the impact of these "clinical recommendations" in the treatment of dyslipidemias or other cardiovascular risk factors within a framework of high global cardiovascular risk (EURO-ASPIRE II, L-TAP, etc.), showed inadequate attention of community-based medicine, disclosed by the insufficient number of subjects investigated and by the large number of untreated or undertreated patients. Rosuvastatin, a recently marketed inhibitor of the 3-hydroxy-3-methylglutaryl coenzyme A reductase, is an effective drug which may normalize high plasma cholesterol among high-risk subjects more often than other similar molecules, thus permitting to reach stringent guideline lipid targets. It is hoped that coronary risk charts based on Italian data will be implemented, with the purpose of better finding and treating those subjects who may benefit, at a suitable level of cardiovascular risk.

Anticholesteremic Agents↗
PubMed2002

Molecular mechanisms of autosomal recessive hypercholesterolemia.

Mutations in the phosphotyrosine-binding domain protein ARH cause autosomal recessive hypercholesterolemia (ARH), an inherited form of hypercholesterolemia due to a tissue-specific defect in the removal of low density lipoproteins (LDL) from the circulation. LDL uptake by the LDL receptor (LDLR) is markedly reduced in the liver but is normal or only moderately impaired in cultured fibroblasts of ARH patients. To define the molecular mechanism underlying ARH we examined ARH mRNA and protein in fibroblasts and lymphocytes from six probands with different ARH mutations. None of the probands had detectable full-length ARH protein in fibroblasts or lymphoblasts. Five probands were homozygous for mutations that introduced premature termination codons. No relationship was apparent between the site of the mutation in ARH and the amount of mRNA. The only mutation identified in the remaining proband was a SINE VNTR Alu (SVA) retroposon insertion in intron 1, which was associated with no detectable ARH mRNA. (125)I-LDL degradation was normal in ARH fibroblasts, as previously reported. In contrast, LDLR function was markedly reduced in ARH lymphoblasts, despite a 2-fold increase in LDL cell surface binding in these cells. These data indicate that all ARH mutations characterized to date preclude the synthesis of full-length ARH and that ARH is required for normal LDLR function in lymphocytes and hepatocytes, but not in fibroblasts. Residual LDLR function in cells that do not require ARH may explain why ARH patients have lower plasma LDL levels than do patients with homozygous familial hypercholesterolemia who have no functional LDLRs.

Adaptor Proteins, Signal Transducing↗
PubMed2002

Autosomal recessive hypercholesterolaemia in Sardinia, Italy, and mutations in ARH: a clinical and molecular genetic analysis.

BACKGROUND: Autosomal recessive hypercholesterolaemia (ARH) is caused by mutations in a putative adaptor protein called ARH. This recessive disorder, characterised by severe hypercholesterolaemia, xanthomatosis, and premature coronary artery disease, is rare except on the island of Sardinia, Italy. Our aim was to ascertain why ARH is more common on Sardinia than elsewhere. METHODS: We obtained detailed medical histories, did physical examinations, measured concentrations of lipoproteins, and harvested genomic DNA from 28 Sardinians with ARH from 17 unrelated families. We sequenced the coding regions and consensus splice sites of ARH in probands from these families, and from 40 individuals of non-Sardinian origin who had an autosomal recessive form of hypercholesterolaemia of unknown cause. FINDINGS: Two ARH mutations, a frameshift mutation (c432insA) in exon 4 (ARH1) and a nonsense mutation (c65G-->A) in exon 1 (ARH2), were present in all of the 17 unrelated families with ARH. Three of the ARH alleles contained both mutations, as a result of an ancient recombination between ARH1 and ARH2. No regional clustering of the three mutant alleles within Sardinia was apparent. Furthermore, four Italians from the mainland with autosomal recessive hypercholesterolaemia were homozygous for ARH1. INTERPRETATION: The small number, high frequency, and dispersed distribution of ARH mutations on Sardinia are consistent with these mutations being ancient and maintained in the Sardinian population because of geographic isolation.

Adolescent↗
PubMed2002

Simvastatin, transdermal patch, and oral estrogen-progestogen preparation in early-postmenopausal hypercholesterolemic women: a randomized, placebo-controlled clinical trial.

Hormone replacement therapy (HRT) seems to have a favorable influence on the plasma lipid profile. Only a few investigations have examined the effects of HRT versus hepatic hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase inhibitors. We compared the relative effects of different hypolipidemic strategies on lipoproteins and coagulative parameters in women with recent-onset spontaneous menopause. In this 24-week, placebo-controlled trial, 60 consecutive healthy women aged >/= 45 years, with amenorrhea from 6 to 60 months (mean, 1.9 +/- 1.4 years), serum follicle stimulating hormone (FSH) greater than 40 U/L, and slight to moderate hypercholesterolemia (low-density lipoprotein-cholesterol [LDL-C] 160 to 250 mg/dL, high-density lipoprotein-cholesterol [HDL-C] < 75 mg/dL, and triglycerides < 200 mg/dL) were enrolled and randomized to dietetic advice (placebo group), simvastatin 10 mg, 0.625 mg of conjugated equine estrogen (CEE), or 50 microg estrogen transdermal patch (ETP). In the latter 2 cases, the progestative nomegestrol was added to estrogens (days 17 to 28 of the cicle). Lipoprotein parameters were evaluated after separating very-low-density lipoproteins (VLDLs) by ultracentrifugation, while fasting glucose and insulin, homocysteine, and hemocoagulative parameters were determined in plasma. Fifty-four patients completed the trial. Total cholesterol (TC) and LDL-C significantly decrased in the simvastatin (-62 mg/dL [-20%] and -72 mg/dL [-30%], respectively), CEE (-42 mg/dL [-13%] and -45 mg/dL [-18%]), and ETP (-30 mg/dL [-10%] and -26 mg/dL [-11%]) groups compared to baseline, but only simvastatin showed an effect significantly superior to diet alone. Apolipoprotein (Apo) B was decreased by simvastatin (-25%, P <.001) and by CEE (-10%, P <.05); again, simvastatin was more effective than either diet or ETP. Triglyceride concentration and VLDL-C were unmodified by treatments. HDL-C and Apo A-I significantly increased in the simvastatin group (+18% and +8%, respectively), while HDL-C was unmodified by both HRT regimens and Apo A-I was reduced by ETP treatment (-17%); lipoprotein[a] (Lp[a]) was decreased by both HRTs (-38%, P <.05, and -22%, P =.07, for CEE and ETP, respectively). Among coagulative parameters, plasminogen activator inhibitor-1 (PAI-1) was significantly reduced by CEE (-29%, P <.05) but not ETP treatment (+16%, P = not significant), while fibrinogen, antithrombin, and homocysteine were unaffected by therapy. Thus, HRT, particularly CEE, seems well tolerated and moderately effective in improving the lipid pattern and, perhaps, the coagulative/fibrinolytic balance in postmenopausal hypercholesterolemic women; it may represent a therapeutic option in slightly dyslipidemic subjects. Statins are preferred in case of more severe disease.

Administration, Cutaneous↗
PubMed2002

Genetic factors associated with the absence of atherosclerosis in octogenarians.

BACKGROUND: Atherosclerosis (ATS) is a common age-related disease of large arteries. The prevalence of older subjects with vascular successful aging (VaSA), defined as the absence of clinical symptoms and instrumental signs of ATS, is low in Western countries. The possible contribution of genetics to the VaSA phenomenon is not known. METHODS: We investigated the distribution of four genetic polymorphisms (angiotensin converting enzyme [ACE], methylenetetrahydrofolate reductase [MTHFR], apolipoprotein E [apo E], and paraoxonase [PON] genes) in 30 subjects with VaSA, 30 subjects with moderate carotid atherosclerosis (ATS group), and 161 controls with a negative history for cardiovascular disease. Clinical examination; ultrasonographic examination of carotid, vertebral, abdominal aortic, iliac, and femoral arteries; and electrocardiogram were performed. RESULTS: The frequency of PON 192 B allele was lower in VaSA patients (13%) compared with ATS patients (37%) and controls (46%) ( p =.06 and.006, respectively); B/B homozygotes were 27% in the ATS group, 12% in controls, and 0% in the VaSA group. The frequency of the MTHFR thermolable + allele was higher in VaSA (0.51) compared with ATS (0.39) and controls (0.40) (VaSA vs C, p =.006). No differences in the distribution of ACE I/D and apo E alleles emerged between the three groups. CONCLUSIONS: The low prevalence of the PON 192 B allele in the VaSA subjects suggests that this polymorphism might have an important role in VaSA, probably by hydrolyzing lipid peroxides and thus preventing low-density lipoprotein from undergoing the oxidative modification. This finding further supports the oxidative hypothesis of ATS.

Aged↗