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Background & Aims: Excessive fructose intake is associated with increased de novo lipogenesis, blood triglycerides, and hepatic insulin resistance. We aimed to determine whether fructose elicits specific effects on lipid metabolism independently of excessive caloric intake., Methods: A total of 94 healthy men were studied in this double-blind, randomized trial. They were assigned to daily consumption of sugar-sweetened beverages (SSBs) containing moderate amounts of fructose, sucrose (fructose-glucose disaccharide) or glucose (80 g/day) in addition to their usual diet or SSB abstinence (control group) for 7 weeks. De novo fatty acid (FA) and triglyceride synthesis, lipolysis and plasma free FA (FFA) oxidation were assessed by tracer methodology., Results: Daily intake of beverages sweetened with free fructose and fructose combined with glucose (sucrose) led to a 2-fold increase in basal hepatic fractional secretion rates (FSR) compared to control (median FSR %/day: sucrose 20.8 (p = 0.0015); fructose 19.7 (p = 0.013); control 9.1). Conversely, the same amounts of glucose did not change FSR (median of FSR %/day 11.0 (n.s.)). Fructose intake did not change basal secretion of newly synthesized VLDL-triglyceride, nor did it alter rates of peripheral lipolysis, nor total FA and plasma FFA oxidation. Total energy intake was similar across groups., Conclusions: Regular consumption of both fructose- and sucrose-sweetened beverages in moderate doses - associated with stable caloric intake - increases hepatic FA synthesis even in a basal state; this effect is not observed after glucose consumption. These findings provide evidence of an adaptative response to regular fructose exposure in the liver., Lay Summary: This study investigated the metabolic effects of daily sugar-sweetened beverage consumption for several weeks in healthy lean men. It revealed that beverages sweetened with the sugars fructose and sucrose (glucose and fructose combined), but not glucose, increase the ability of the liver to produce lipids. This change may pave the way for further unfavorable effects on metabolic health., Clinical Trial Registration Number: NCT01733563., Competing Interests: Conflict of interest The authors have declared that no conflicts of interest exist with regard to this study. Please refer to the accompanying ICMJE disclosure forms for further details., (Copyright © 2021 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Background: Sugar-sweetened beverages (SSBs) have unfavorable effects on glucose and lipid metabolism if consumed in high quantities by obese subjects, but the effect of lower doses in normal-weight subjects is less clear., Objective: The aim was to investigate the effects of SSBs consumed in small to moderate quantities for 3 wk on LDL particle distribution and on other parameters of glucose and lipid metabolism as well as on inflammatory markers in healthy young men., Design: Twenty-nine subjects were studied in a prospective, randomized, controlled crossover trial. Six 3-wk interventions were assigned in random order as follows: 600 mL SSBs containing 1)40 g fructose/d [medium fructose (MF)], 2) 80 g fructose/d [high fructose (HF)], 3) 40 g glucose/d [medium glucose (MG)], 4) 80 g glucose/d [high glucose (HG)], 5) 80 g sucrose/d [high sucrose (HS)], or 6) dietary advice to consume low amounts of fructose. Outcome parameters were measured at baseline and after each intervention., Results: LDL particle size was reduced after HF by -0.51 nm (95% CI: -0.19, -0.82 nm) and after HS by -0.43 nm (95% CI: -0.12, -0.74; P < 0.05 for both). Similarly, a more atherogenic LDL subclass distribution was seen when fructose-containing SSBs were consumed (MF, HF, and HS: P < 0.05). Fasting glucose and high-sensitivity C-reactive protein (hs-CRP) increased significantly after all interventions (by 4-9% and 60-109%, respectively; P < 0.05); leptin increased during interventions with SSBs containing glucose only (MG and HG: P < 0.05)., Conclusion: The present data show potentially harmful effects of low to moderate consumption of SSBs on markers of cardiovascular risk such as LDL particles, fasting glucose, and hs-CRP within just 3 wk in healthy young men, which is of particular significance for young consumers. This trial was registered at clinicaltrials.gov as NCT01021969.

Objective: Subjects with rheumatoid arthritis (RA) have increased cardiovascular risk and may show atherogenic forms of dyslipidemia. The present study investigated whether patients with early RA, beyond alterations in plasma lipids, also show lower LDL size and altered LDL subclass distribution., Design and Methods: We identified 25 subjects with RA (47+/-8 years, body mass index (BMI) 25+/-4kg/m(2)) by the American College of Rheumatology diagnostic criteria, with a disease durations <1 year and no prior treatment against it. In patients and 22 healthy subjects matched for age and BMI (controls) we measured plasma lipids and LDL size and subclasses by gradient gel electrophoresis., Results: As compared to controls RA patients had higher plasma triglycerides (1.8+/-0.5 vs. 1.0+/-0.5mmol/L, p<0.0001) and lower HDL-cholesterol concentrations (1.2+/-0.2 vs. 1.4+/-0.2mmol/L, p=0.0027), while total- and LDL-cholesterol concentrations were similar. LDL particle size was lower in RA patients than controls (264+/-7 vs. 281+/-9A, p<0.0001), due to less LDL-I (31+/-6 vs. 38+/-7%, p=0.0004) and LDL-IIA (14+/-3 vs. 16+/-3%, p=0.0182), and more LDL-IIIB (7+/-1 vs. 5+/-1%), -IVA (11+/-2 vs. 8+/-2%) and -IVB particles (12+/-2 vs. 9+/-2%,) (p<0.0001 for all). Further, about 1/3 of patients showed the complete "atherogenic-lipoprotein-phenotype" (e.g. the concomitant presence of high triglycerides, low HDL-cholesterol and elevated small, dense LDL)., Conclusions: Beyond plasma lipids, increased levels of small, dense LDL seems to be common in drug-naïve patients with early RA. Yet, whether these findings affect the atherogenic process and the clinical endpoints in these subjects remains to be determined by future prospective studies.

Background: Recent findings have suggested that subjects with non-coronary atherosclerosis may show elevated prevalence of atherogenic dyslipidemia, including higher triglyceride levels, reduced HDL-cholesterol concentrations and increased levels of small, dense low-density lipoproteins (LDL). These three lipid abnormalities constitute the so-called "atherogenic-lipoprotein-phenotype" (ALP) but its predictive role in these patients still remains to be established., Methods: We performed a 2-year follow-up study to assess clinical and biochemical predictors of cardiovascular events in 44 male patients (64+/-5 years, BMI: 27+/-3), 26 with peripheral arterial disease and 18 with abdominal aortic aneurysm. Beyond traditional cardiovascular risk factors, we measured LDL size and subclasses by gradient gel electrophoresis., Results: Clinical events were registered in the 43% of patients. At univariate analysis we found that patients with events had increased prevalence of hypertension (p=.0098), diabetes (p=.0089), family history of cardiovascular diseases (p=.0089), of elevated small, dense LDL (p=.0222) and ALP (p=.0224). At multivariate analysis (including all clinical and laboratory variables) we found the following independent predictors of events: hypertension (OR 8.9, p=.0347), diabetes (OR 9.4, p=.0270), elevated small, dense LDL (OR 6.9, p=.0488) and ALP (OR 8.7, p=.0497)., Conclusions: This is the first study that evaluated the predictive role of ALP beyond traditional cardiovascular risk factors in patients with peripheral arterial disease or abdominal aortic aneurysm. We confirmed that hypertension and diabetes are strong predictors of cardiovascular events in these subjects but ALP seems to be an independent predictor too. Yet, the therapeutical consequences of these findings need to be tested by future studies.

Ezetimibe represents the first of a new class of agents, the cholesterol absorption inhibitors, able to reduce low-density lipoproteins (LDL)-cholesterol by 15-25% from baseline in monotherapy and on top of statins and fibrates. To-date all the data regarding the efficacy of ezetimibe comes from the studies of its lipid-lowering power. Yet, recent findings from the ENHANCE study on atherosclerosis progression showed that the addition of ezetimibe to simvastatin in patients with heterozygous familial hypercholesterolemia did not affect the mean change in carotid intima-media thickness, although a significant reduction in LDL-cholesterol levels was present. Therefore, we cannot exclude that ezetimibe is treating mainly LDL-cholesterol and not the underlying dyslipidemia. Reviewing all available evidences on the effects on atherogenic small, dense LDL, it seems that ezetimibe produce quantitative rather than qualitative changes in LDL, with small net effects on LDL subclass distribution. Yet, we cannot exclude that clinical and laboratory factors influenced this result. We found important differences in the methodology used to measure LDL size and subfractions and this represents a crucial point, since these methods cannot be fully used interchangeably. In addition, it is reasonable to imagine that ezetimibe may be more effective on small, dense LDL in subjects with hypertriglyceridemia. Further formal cardiovascular event outcome trials are underway and this will provide additional insights into the long-term effects of ezetimibe. Future prospective studies are also needed to clarify to which extent ezetimibe is able to reduce atherogenic dyslipidemia, beyond LDL-cholesterol levels.

Background: High amounts of dietary fructose may contribute to dyslipidemia in adults, but there are few data in children. Childhood adiposity is associated with smaller LDL particle size, but the dietary predictors of LDL size in overweight children have not been studied., Objectives: We aimed to determine whether LDL particle size is associated with dietary factors and specifically with fructose intake in normal-weight and overweight children., Design: In a cross-sectional study of normal-weight and overweight 6-14 y-old Swiss children (n = 74), dietary intakes were assessed by using two 24-h-recalls and a 1-d dietary record. Body mass index (BMI) and waist-hip ratio (WHR) were measured, and plasma lipid profile and LDL particle size were determined., Results: Compared with the normal-weight group, overweight children had significantly higher plasma triacylglycerol concentrations, lower HDL-cholesterol concentrations, and smaller LDL particle size (P < 0.05). LDL particle size was inversely correlated to BMI SD scores and WHR (P = 0.007). Although there were no significant differences in total fructose intake, the overweight children consumed a significantly (P < 0.05) higher percentage of fructose from sweets and sweetened drinks than did the normal-weight children. After control for adiposity, the only dietary factor that was a significant predictor of LDL particle size was total fructose intake (P = 0.024)., Conclusions: In school-age children, greater total and central adiposity are associated with smaller LDL particle size and lower HDL cholesterol. Overweight children consume more fructose from sweets and sweetened drinks than do normal-weight children, and higher fructose intake predicts smaller LDL particle size.

Background: Traditional criteria to diagnose hyperinsulinaemic hypoglycaemia are based on insulin measurements by unspecific insulin assays. This study was performed to test whether these traditional criteria can be applied when insulin is measured by specific immunoassays., Methods: 29 consecutive patients undergoing a prolonged fast were included; 11 patients with insulinoma and 18 healthy individuals. We determined plasma glucose, insulin, C-peptide, proinsulin, and beta-hydroxybutyrate concentrations at the termination of the fast. Insulin was measured by an unspecific radioimmunoassay (RIA) and a specific enzyme-linked immunosorbent assay (ELISA)., Results: In 11 insulinoma patients, insulin concentrations at median plasma glucose concentration of 2.1 (range 1.3-2.5) mmol/l were 170 (76-340) pmol/l measured by RIA and 61 (11-156) pmol/l by ELISA. Insulin concentrations measured by RIA confirmed hyperinsulinaemia (i.e., >36 pmol/l, the proposed cut-off value for traditional insulin assays) in all insulinoma patients, whereas insulin concentrations measured by ELISA were <36 pmol/l in four patients. In three insulinoma patients, insulin concentrations measured by ELISA were <18 pmol/l, a proposed cut-off level to diagnose hyperinsulinaemia for specific insulin assays., Conclusion: When insulin concentrations are measured by specific immunoassays in patients evaluated for fasting hypoglycaemia, traditional reference values cannot be applied.

Background: Serum cystatin C (CysC) is a novel marker for kidney function. The impact of mild thyroid dysfunction on CysC has never been investigated., Methods: CysC was determined at the time of diagnosis of subclinical hypo- and hyperthyroidism, and when TSH returned into the normal range in 40 consecutive patients with mild thyroid dysfunction., Results: Twenty-six patients with subclinical hypothyroidism and 14 patients with subclinical hyperthyroidism were included. In patients with subclinical hypothyroidism median (range) TSH was 7.8 (4.3-26.7) mU/l (reference 0.27-4.2) at diagnosis and decreased to 2.3 (0.36-4.0) mU/l following treatment with levothyroxine. Mean (+/-S.D.) CysC increased from 0.88+/-0.23 mg/l (reference 0.63-1.33) in the hypothyroid state to 1.01+/-0.21 mg/l when TSH normalized (p<0.001). In patients with subclinical hyperthyroidism, median TSH at diagnosis was 0.08 (0.001-0.26) mU/l and increased to 1.6 (0.28-4.0) mU/l in the euthyroid state. CysC declined from 1.04+/-0.29 mg/l at diagnosis of subclinical hyperthyroidism to 0.91+/-0.25 mg/l when TSH normalized (p<0.05)., Conclusions: Mild thyroid dysfunction significantly alters CysC levels. Therefore, thyroid function has to be considered when CysC is used as a marker of kidney function.

Background: Magnesium deficiency has been associated with type 2 diabetes and may reduce insulin sensitivity and impair glucose tolerance. The etiology of magnesium depletion in diabetes is unclear. Animal studies suggest that diabetes may impair magnesium absorption; however, there are no published data on magnesium absorption in humans with diabetes., Objective: Magnesium absorption from a test meal and the excretion and retention of magnesium were compared between patients with type 2 diabetes and healthy control subjects., Design: A meal labeled with 10 mg (26)Mg isotopic label was administered, and stool and urine samples were collected for 10 and 6 d, respectively. Apparent absorption was calculated as the difference between the oral dose of (26)Mg isotopic label and the total amount of the isotopic label excreted in the feces. Magnesium retention was calculated from the apparent absorption and urinary excretion of (26)Mg isotopic label in the 6 d after administration., Results: Mean (+/- SD) values for fractional magnesium absorption in the diabetic patients and the control subjects were 59.3 +/- 7.0% and 57.6 +/- 8.5%, respectively (NS). Mean (+/- SD) urinary magnesium excretion values in the diabetic patients and the control subjects were 11.2 +/- 2.6% and 11.7 +/- 3.8%, respectively (NS); retention values were 54.2 +/- 7.1% and 51.4 +/- 6.1%, respectively (NS)., Conclusion: Dietary magnesium absorption and retention are not impaired in patients with reasonably well-controlled type 2 diabetes.