Preheparin serum lipoprotein lipase mass might be a biomarker of metabolic syndrome

Relationship between Lipoprotein Lipase Derived from Subcutaneous Adipose Tissue and Cardio-Ankle Vascular Index in Japanese Patients with Severe Obesity

INTRODUCTION

Cardio-ankle vascular index (CAVI) is an arterial stiffness index that correlates inversely with body mass index (BMI) and subcutaneous fat area. Lipoprotein lipase (LPL) that catalyzes the hydrolysis of serum triglycerides is produced mainly in adipocytes. Serum LPL mass reflects LPL expression in adipose tissue, and its changes correlate inversely with changes in CAVI. We hypothesized that LPL derived from subcutaneous adipose tissue (SAT) suppresses the progression of arteriosclerosis and examined the relationship of LPL gene expression in different adipose tissues and serum LPL mass with CAVI in Japanese patients with severe obesity undergoing laparoscopic sleeve gastrectomy (LSG).

METHODS

This study was a single-center retrospective database analysis. Fifty Japanese patients who underwent LSG and had 1-year postoperative follow-up data were enrolled (mean age 47.5 years, baseline BMI 46.6 kg/m2, baseline HbA1c 6.7%). SAT and visceral adipose tissue (VAT) samples were obtained during LSG surgery. LPL gene expression was analyzed by real-time PCR. Serum LPL mass was measured by ELISA using a specific monoclonal antibody against LPL.

RESULTS

At baseline, LPL mRNA expression in SAT correlated positively with serum LPL mass, but LPL mRNA expression in VAT did not. LPL mRNA expression in SAT was correlated, and serum LPL mass tended to correlate inversely with the number of metabolic syndrome symptoms, but LPL mRNA expression in VAT did not. LPL mRNA expression in SAT and CAVI tended to correlate inversely in the group with visceral-to-subcutaneous fat ratio of 0.4 or higher, which is considered metabolically severe. Serum LPL mass increased 1 year after LSG. Change in serum LPL mass at 1 year after LSG tended to be an independent factor inversely associated with change in CAVI.

CONCLUSIONS

Serum LPL mass reflected LPL mRNA expression in SAT in Japanese patients with severe obesity, and LPL mRNA expression in SAT was associated with CAVI in patients with visceral obesity. The change in serum LPL mass after LSG tended to independently contribute inversely to the change in CAVI. This study suggests that LPL derived from SAT may suppress the progression of arteriosclerosis.

Effects of Vildagliptin, a Dipeptidyl Peptidase-4 Inhibitor, on the Parameters of Glucose Metabolism and the Cardio-Ankle Vascular Index in Individuals with Type 2 Diabetes

DPP-4 inhibitors are frequently used as first-line agents for the treatment of type 2 diabetes in Japan. This study aimed to examine the effects of vildagliptin on glucose metabolism and arterial stiffness. Twenty treatment-naïve patients with type 2 diabetes (8 males and 12 females) received vildagliptin 50 mg twice daily for 6 months. Self-monitored blood glucose measurements and a 75 g OGTT were performed. Arterial stiffness was assessed using the CAVI. After the vildagliptin treatment, a significant decrease in the median HbA1c (from 8.3 to 6.4%) and fasting HOMA-β (from 26.1 to 34.5%), and a marginally significant decrease in the CAVI (from 8.9 to 8.4, p = 0.087) were observed. The glycemic variability parameters also improved, whereas the insulin sensitivity and oxidative stress remained unchanged. Participants with a lower glycemic variability on the 75 g OGTT after vildagliptin treatment showed a significant decrease in their CAVI. The baseline BMI was significantly higher for the participants with a decreased CAVI than in those with no change in their CAVI (24.5 vs. 20.8 kg/m2). After vildagliptin treatment, a decrease in the CAVI was observed, especially in the individuals with improved glycemic variability on the 75 g OGTT. Vildagliptin may be suitable for vascular protection in individuals with high glycemic variability and/or an elevated BMI.

The Effects of Smoking on the Diagnostic Characteristics of Metabolic Syndrome: A Review

Metabolic syndrome is a growing epidemic that increases the risk for cardiovascular disease, diabetes, stroke, and mortality. It is diagnosed by the presence of three or more of the following risk factors: 1) obesity, with an emphasis on central adiposity, 2) high blood pressure, 3) hyperglycemia, 4) dyslipidemia, with regard to reduced high-density lipoprotein concentrations, and 5) dyslipidemia, with regard to elevated triglycerides. Smoking is one lifestyle factor that can increase the risk for metabolic syndrome as it has been shown to exert negative effects on abdominal obesity, blood pressure, blood glucose concentrations, and blood lipid profiles. Smoking may also negatively affect other factors that influence glucose and lipid metabolism including lipoprotein lipase, adiponectin, peroxisome proliferator-activated receptors, and tumor necrosis factor-alpha. Some of these smoking-related outcomes may be reversed with smoking cessation, thus reducing the risk for metabolic disease; however, metabolic syndrome risk may initially increase post cessation, possibly due to weight gain. Therefore, these findings warrant the need for more research on the development and efficacy of smoking prevention and cessation programs.

Carbonylated Proteins as Key Regulators in the Progression of Metabolic Syndrome

Based on the known role of oxidative stress in the pathogenesis and progression of metabolic syndrome, we used two-dimensional gel electrophoresis with immunochemical detection of protein carbonyls (2D-Oxyblot) to characterize the carbonylated proteins induced by oxidative stress in spontaneously hypertensive rats/NDmcr-cp (CP), an animal model of metabolic syndrome. We also profiled the proteins that showed change of expression levels in their epididymal adipose tissue at the pre-symptomatic (6-week-old) and the symptomatic (25-week-old) stages of the metabolic syndrome. Two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) combined with matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS) was used to analyze proteins extracted from the epididymal adipose tissue. The up-regulated proteins identified at the pre-symptomatic stage were mainly associated with ATP production and redox reaction, while the down-regulated proteins found at the symptomatic stage were involved in antioxidant activity and the tricarboxylic acid (TCA) cycle. Further analysis using the 2D-Oxyblot showed significantly high carbonylation levels of gelsolin and glycerol-3-phosphate dehydrogenase [NAD+] at the symptomatic stage. These results suggest that reduced antioxidant capacity underlies the increased oxidative stress state in the metabolic syndrome. The identified carbonylated proteins, including gelsolin, are potential targets that may act as key regulators in the progression of the metabolic syndrome.

Data-independent acquisition proteomics reveals circulating biomarkers of coronary chronic total occlusion in humans

Introduction

The pathophysiology of coronary chronic total occlusion (CTO) has not been fully elucidated.

Methods

In the present study, we aimed to investigate the potential plasma biomarkers associated with the pathophysiologic progression of CTO and identify protein dynamics in the plasma of CTO vessels immediately after successful revascularization. We quantitatively analyzed the plasma proteome profiles of controls (CON, n = 10) and patients with CTO pre- and post- percutaneous coronary intervention (PCI) (CTO, n = 10) by data-independent acquisition proteomics. We performed enzyme-linked immunosorbent assay (ELISA) to further confirm the common DEPs in the two-group comparisons (CON vs. CTO and CTO vs. CTO-PCI).

Results

A total of 1936 proteins with 69 differentially expressed proteins (DEPs) were detected in the plasma of patients with CTO through quantitative proteomics analysis. For all these DEPs, gene ontology (GO) analysis and protein-protein interaction (PPI) analysis were performed. The results showed that most of the proteins were related to the negative regulation of proteolysis, regulation of peptidase activity, negative regulation of hydrolase activity, humoral immune response, and lipid location. Furthermore, we identified 1927 proteins with 43 DEPs in the plasma of patients with CTO vessels after immediately successful revascularization compared to pre-PCI. GO analysis revealed that the above DEPs were enriched in the biological processes of extracellular structure organization, protein activation cascade, negative regulation of response to external stimulus, plasminogen activation, and fibrinolysis. More importantly, we generated a Venn diagram to identify the common DEPs in the two-group comparisons. Seven proteins, ADH4, CSF1, galectin, LPL, IGF2, IgH, and LGALS1, were found to be dynamically altered in plasma during the pathophysiological progression of CTO vessels and following successful revascularization, moreover, CSF1 and LGALS1 were validated via ELISA.

Conclusions

The results of this study reveal a dynamic pattern of the molecular response after CTO vessel immediate reperfusion, and identified seven proteins which would be the potential targets for novel therapeutic strategies to prevent coronary CTO.

Maternal Blood-Based Protein Biomarkers in Relation to Abdominal Fat Distribution Measured by Ultrasound in Early Mid-Pregnancy

The objective of this study was to examine the associations of early mid-pregnancy ultrasound measured visceral and subcutaneous fat depths with blood-based protein biomarkers. This was a cross-sectional study including 201 pregnant women at Uppsala University Hospital, Sweden. The mean age of the women was 31.0 years, and 57.7% were nulliparous. Maternal visceral and subcutaneous fat depths were measured by ultrasound at the early second-trimester anomaly scan. A non-fasting blood sample was collected in conjunction with the second-trimester anomaly scan, and the Olink cardiovascular II panel was used to measure 92 blood-based protein biomarkers in the sample. Cross-sectional associations of visceral and subcutaneous fat depths with blood-based protein biomarkers were examined using Mann-Whitney U tests with false discovery rate adjustments. In addition, linear regression analyses adjusting for maternal age, parity, and early pregnancy body mass index were performed. The results showed differences in one biomarker between women with elevated (≥ 52 mm) versus normal (< 52 mm) visceral fat depth, and in three biomarkers between women with elevated (≥ 22 mm) versus normal (< 22 mm) subcutaneous fat depth. Hence, levels of blood-based protein biomarkers differ between pregnant women with dissimilar body fat distributions, which might reflect disparities in biological pathways.

Determinants of type 2 diabetes remission after bariatric surgery in obese Japanese patients: a retrospective cohort study

Objective

Bariatric surgery (BS) improves glycemic control in type 2 diabetes; however, some patients show insufficient improvement. Understanding the pathophysiology of type 2 diabetes in obese patients can facilitate appropriate treatment for type 2 diabetes after BS. The homeostatic model assessment (HOMA) 2 enables the calculation of the values from C-peptide data and evaluation of insulin users. We aimed to evaluate the pathophysiology of type 2 diabetes using pre- and postoperative parameters and HOMA2 in obese patients who underwent BS.

Methods

We retrospectively reviewed data from 45 obese patients with type 2 diabetes who underwent BS. They were followed-up for 12 months. The relationship between the HOMA2 score and complete remission (CR) of type 2 diabetes after BS was analyzed. Patients with and without CR were assigned to the CR and non-CR groups, respectively. Multiple regression analysis was used to identify factors associated with improvement in type 2 diabetes after BS.

Results

BS significantly improved body weight and glucose metabolism. The preoperative glycosylated hemoglobin A1c level and insulin secretion (HOMA2-%B) significantly differed between the CR and non-CR groups. Postoperative weight reduction and improved insulin sensitivity correlated significantly with CR; multiple regression showed that the preoperative HOMA 2-%B independently predicted CR of type 2 diabetes after BS.

Conclusion

Preoperative insulin secretion, improvement in insulin sensitivity, and weight reduction after BS are related to CR of type 2 diabetes after BS. The results better reveal the pathophysiology of and treatment for type 2 diabetes in obese patients who undergo BS.

Case Report: Various Abnormalities in Lipid and Glucose Metabolism Induced by Capecitabine

Capecitabine has been used for the treatment of various types of tumors. The rare side effects induced by capecitabine have been reported as hypertriglyceridemia, acute pancreatitis associated with hypertriglyceridemia and hypertriglyceridemia complicated with hyperglycemia. The mechanisms of capecitabine-induced hypertriglyceridemia are unclear. In this report, we present a subject with sigmoid colon cancer and capecitabine-induced dyslipidemia. LDL-cholesterol level was markedly elevated throughout the long period of treatment with capecitabine. In addition, triglyceride level was high and not stable during the treatment period. Her dyslipidemia was ameliorated by the treatment with 5 mg of rosuvastatin, which is one of the HMG-CoA reductase inhibitors.

Individualization of the infusion rate of a soybean oil-based intravenous lipid emulsion for inpatients, based on baseline triglyceride concentrations: A population pharmacokinetic approach

BACKGROUND

A rapid infusion rate for intravenous lipid emulsion (ILE) can cause adverse effects; therefore, safe and efficient infusion rates are desired. This study aimed to develop a triglyceride (TG) kinetic model after soybean oil-based ILE (SO-ILE) administration and individualize the infusion rate via a population pharmacokinetic approach.

METHODS

Eighty-three inpatients were enrolled in this prospective observational study. A TG kinetic model was applied to the observations based on population pharmacokinetics using a nonlinear mixed-effect model. The patients' characteristics and laboratory parameters were evaluated to identify predictors of TG kinetics, and the maximum acceptable infusion rate was defined as that for which the maximum TG concentration did not exceed 400 mg/dl in 90% of patients.

RESULTS

No adverse events associated with SO-ILE administration were observed. The developed TG kinetic model explained the observed TG concentrations and identified the baseline TG concentration and body weight as predictors of TG kinetics. The estimated maximum acceptable infusion rates greatly varied among individuals, ranging from <0.01 to 0.3 g/kg/h.

CONCLUSION

The present study suggested the necessity and demonstrated the feasibility of individualizing the infusion rates of SO-ILE, using a population pharmacokinetic approach.

GIP Receptor Antagonist, SKL-14959 Indicated Alteration of the Lipids Metabolism to Catabolism by the Inhibition of Plasma LPL Activity, Resulting in the Suppression of Weight Gain on Diets-Induced Obesity Mice

INTRODUCTION

Glucose-dependent insulinotropic polypeptide (GIP) plays a crucial role in the regulation of lipid metabolism via lipoprotein lipase (LPL). GIP receptor antagonist, SKL-14959, suppressed the weight gain in the diet-induced obesity model. However, the mechanism is not unclear. Therefore, we aimed to give insight into the reason.

METHODS

Mice were divided into three groups of the low-fat diet, high-fat diets mixture with or without SKL-14959 for 151 days, and were monitored body weight and food consumption through the test. Oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were also performed. After that, blood, liver, muscle and adipose tissue were collected. Blood samples were measured glycosylated hemoglobin A1c (HbA1c), glucose, insulin, GIP level and plasma LPL activity. Triacylglycerol (TG) contents of liver and muscles were also measured. Moreover, a simple correlation analysis was performed.

RESULTS

SKL-14959 suppressed the body weight gain, decreased body mass index (BMI), HbA1c, and fasting glucose level, and trended to decline adipose tissues weight and TG contents compared with the vehicle, and inhibited plasma LPL activity. OGTT and ITT in the SKL-14959 group were not significantly changed relative to the vehicle. Additionally, upon treatment with SKL-14959 treatment, weight gain had weak correlation with lipase activity. Furthermore, lipase activity was associated with the fat mass and not white but red muscle TG contents and liver TG contents were not associated with lipase activity but HbA1c.

IN CONCLUSION

SKL-14959 might direct lipids metabolism to catabolism by inhibition of plasma LPL activity, resulting in the suppression of weight gain on diets-induced obesity mice.

Prevention of Cardiovascular Events with Pitavastatin is Associated with Increased Serum Lipoprotein Lipase Mass Level: Subgroup Analysis of the TOHO-LIP

Aim: To clarify the mechanism by which pitavastatin reduced cardiovascular (CV) events more effectively than atorvastatin in the TOHO Lipid Intervention Trial Using Pitavastatin (TOHO-LIP), the changes in (Δ) non-heparinized serum level of lipoprotein lipase mass (LPL mass) during administration of the respective statins were investigated.

Methods: From TOHO-LIP data, 223 hypercholesterolemic patients with any CV risks followed at Toho University Sakura Medical Center were analyzed. The patients were randomized to pitavastatin (2 mg/day) group ( n =107) or atorvastatin (10 mg/day) group ( n =116), and followed for 240 weeks. In this subgroup study, the primary and secondary end points were the same as those in TOHO-LIP, and 3-point major adverse cardiovascular events (3P-MACE) was added. The relationship between ΔLPL mass during the first year and the incidences of each end point was analyzed.

Results: The lipid-lowering effect was not different between the two statins. Cumulative 240-week incidence of each end point was significantly lower in pitavastatin group (primary: 1.9% vs. 10.3%, secondary: 4.7% vs. 18.1%, 3P-MACE: 0.9% vs. 6.9%). Mean LPL mass (64.9 to 69.0 ng/mL) and eGFR (70.1 to 73.6 ml/min/1.73m ² ) increased in pitavastatin group, but not in atorvastatin group during the first year. Cox proportional-hazards model revealed that ΔLPL mass (1 ng/mL or 1SD) contributed to almost all end points.

Conclusions: Pitavastatin administration reduced CV events more efficaciously than atorvastatin despite similar LDL cholesterol-lowering effect of the two statins. Increased LPL mass during the first year by pitavastatin treatment may be associated with this efficacy.

Background characteristics and diabetes remission after laparoscopic sleeve gastrectomy in Japanese patients with type 2 diabetes stratified by BMI: subgroup analysis of J-SMART

Aim

The J-SMART study was the first national survey of Japanese patients undergoing laparoscopic sleeve gastrectomy (LSG). We performed a subgroup analysis of J-SMART focusing on the differences in patient background and diabetes remission between patients with BMI 32-34.9 kg/m² and those with higher BMI.

Methods

In this multi-institutional retrospective study at 10 certified bariatric institutions, 203 Japanese with type 2 diabetes (T2D) and BMI of 32 kg/m² or higher were analyzed (mean age: 49.2 years, BMI: 43.8 kg/m², HbA1c: 7.6%). Patients were stratified into five groups according to preoperative BMI.

Results

Background characteristics in BMI 32.0-34.9 group were higher adjusted HbA1c, higher visceral/subcutaneous fat area ratio, higher prevalence of diabetic retinopathy, higher frequency of insulin use and lower serum C-peptide. Although 2-year percent total weight loss (21.7%) and diabetes complete remission (CR) rate (52.4%) were lower in BMI 32.0-34.9 group, diabetes improvement rate was 81.0%, and the decrease in HbA1c and number of antidiabetic drugs were comparable or greater than those with higher BMI. Higher BMI and no insulin use were significant independent predictors of diabetes CR. No significant independent predictor was identified for diabetes improvement.

Conclusion

The patients with 32-34.9 kg/m² were characterized by more severe visceral obesity, T2D and the complications, and lower intrinsic insulin secretion capacity. LSG should be considered as a treatment option for patients with BMI 32-34.9 kg/m², to improve diabetes control.

The Prevalence of Metabolic Syndrome in Ethiopian Population: A Systematic Review and Meta-analysis

Background

The metabolic syndrome is a clustering of hyperglycemia/insulin resistance, hypertension, dyslipidemia, and obesity which are risk factors for cardiovascular disease, type 2 diabetes and stroke, and all-cause mortality. The burden of metabolic syndrome is emerging alarmingly in low- and middle-income countries such as Ethiopia; however, there is lack of comprehensive estimation. This study aimed to determine the pooled prevalence of metabolic syndrome in Ethiopia.

Methods

This systematic review and meta-analysis included original articles of observational studies published in the English language. Searches were carried out in PubMed, Google Scholar, and Africa Journals from conception to August 2020. A random-effects model was used to estimate the pooled prevalence of metabolic syndrome in Ethiopia. Heterogeneity was assessed using the I 2 statistic. Subgroup analysis was also conducted based on sex/gender and study subjects. Egger's test was used to assess publication bias.

Results

Electronic and gray literature search retrieved 942 potentially relevant papers. After removing duplicates and screening with eligibility criteria, twenty-eight cross-sectional studies were included in this meta-analysis. The pooled prevalence of metabolic syndrome in Ethiopia was found to be 34.89% (95% CI: 26.77, 43.01) and 27.92% (95% CI: 21.32, 34.51) by using NCEP/ATP III and IDF criteria, respectively. The weighted pooled prevalence of metabolic syndrome was higher in females 36.74% (95% CI: 20.72, 52.75) and 34.09% (95% CI: 26.68, 41.50) compared to males 22.22% (95% CI: 14.89, 29.56) and 24.82% (95% CI: 18.34, 31.31) by using IDF and NCEP/ATP III criteria, respectively. Subgroup analysis based on the study subjects using NCEP/ATP III showed that the weighted pooled prevalence was 63.78%(95% CI: 56.17, 71.40), 44.55% (95% CI: 30.71, 52.38), 23.09% (95% CI: 19.74, 26.45), 20.83% (95% CI: 18.64, 23.01), and 18.45% (95% CI: 13.89, 23.01) among type 2 diabetes patients, hypertensive patients, psychiatric patients, HIV patients on HAART, and working adults, respectively. The most frequent metabolic syndrome components were low HDL-C 51.0% (95% CI: 42.4, 59.7) and hypertriglyceridemia 39.7% (95% CI: 32.8, 46.6).

Conclusions

The findings revealed an emerging high prevalence of metabolic syndrome in Ethiopia. Therefore, early intervention is required for the primary prevention of the occurrence of metabolic syndrome and the further reduction of the morbidity and mortality related to it.

Maternal Adipose Tissue Expansion, A Missing Link in the Prediction of Birth Weight Centile

CONTEXT

Maternal body mass index (BMI) is associated with increased birth weight but does not explain all the variance in fetal adiposity.

OBJECTIVE

To assess the contribution of maternal body fat distribution to offspring birth weight and adiposity.

DESIGN

Longitudinal study throughout gestation and at delivery.

SETTING

Women recruited at 12 weeks of gestation and followed up at 26 and 36 weeks. Cord blood was collected at delivery.

PATIENTS

Pregnant women (n = 45) with BMI 18.0 to 46.3 kg/m2 and healthy pregnancy outcome.

METHODS

Maternal first trimester abdominal subcutaneous and visceral adipose tissue thickness (SAT and VAT) was assessed by ultrasound.

MAIN OUTCOME MEASURES

Maternal body fat distribution, maternal and cord plasma glucose and lipid concentrations, placental weight, birth weight, and fetal adiposity assessed by cord blood leptin.

RESULTS

VAT was the only anthropometric measure independently associated with birth weight centile (r2 adjusted 15.8%, P = .002). BMI was associated with trimester 2 and trimesters 1 through 3 area under the curve (AUC) glucose and insulin resistance (Homeostatic Model Assessment). SAT alone predicted trimester 2 lipoprotein lipase (LPL) mass (a marker of adipocyte insulin sensitivity) (11.3%, P = .017). VAT was associated with fetal triglyceride (9.3%, P = .047). Placental weight was the only independent predictor of fetal adiposity (48%, P < .001). Maternal trimester 2 and AUC LPL were inversely associated with fetal adiposity (r = -0.69, P = .001 and r = -0.58, P = .006, respectively).

CONCLUSIONS

Maternal VAT provides additional information to BMI for prediction of birth weight. VAT may be a marker of reduced SAT expansion and increased availability of maternal fatty acids for placental transport.

Severe hypertriglyceridemia in a subject with disturbed life style and poor glycemic control without recurrence of acute pancreatitis: a case report

BACKGROUND

Hypertriglyceridemia is often observed as the result of lipid abnormality and frequently associated with other lipid and metabolic disorders. Aggravation of hypertriglyceridemia is caused by various conditions. However, severe hypertriglyceridemia is usually induced by an addition of some secondary clinical conditions such as uncontrolled type 2 diabetes mellitus (T2DM) and obesity with insulin resistance.

CASE PRESENTATION

A 40-year-old man with 4-year history of dyslipidemia and T2DM visited after his interruption of therapy for about 1.5 years. His past history was acute pancreatitis. His life style was markedly disturbed, and he had a lot of risk factors for hypertriglyceridemia. Surprisingly, his serum triglyceride level was as high as 16,900 mg/dL. His aggravation and remission of hypertriglyceridemia were closely associated with the alteration of RLP-cholesterol levels in dyslipidemia and glycoalbumin and ketone body levels in T2DM.

CONCLUSION

We report very severe hypertriglyceridemia, which seemed to be caused by markedly disturbed life style and poorly controlled T2DM. Total therapy with diet and drug for each disease is very important for the improvement of very severe hypertriglyceridemia. This case report suggests that very severe hypertriglyceridemia alone does not necessarily bring out acute pancreatitis, although it is very important to check pancreatitis markers in such a situation.

Association between skeletal muscle mass and serum concentrations of lipoprotein lipase, GPIHBP1, and hepatic triglyceride lipase in young Japanese men

Background

Two important regulators for circulating lipid metabolisms are lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL). In relation to this, glycosylphosphatidylinositol anchored high-density lipoprotein binding protein 1 (GPIHBP1) has been shown to have a vital role in LPL lipolytic processing. However, the relationships between skeletal muscle mass and lipid metabolism, including LPL, GPIHBP1, and HTGL, remain to be elucidated. Demonstration of these relationships may lead to clarification of the metabolic dysfunctions caused by sarcopenia. In this study, these relationships were investigated in young Japanese men who had no age-related factors; participants included wrestling athletes with abundant skeletal muscle.

Methods

A total of 111 young Japanese men who were not taking medications were enrolled; 70 wrestling athletes and 41 control students were included. The participants’ body compositions, serum concentrations of lipoprotein, LPL, GPIHBP1 and HTGL and thyroid function test results were determined under conditions of no extreme dietary restrictions and exercises.

Results

Compared with the control participants, wrestling athletes had significantly higher skeletal muscle index (SMI) (p < 0.001), higher serum concentrations of LPL (p < 0.001) and GPIHBP1 (p < 0.001), and lower fat mass index (p = 0.024). Kruskal–Wallis tests with Bonferroni multiple comparison tests showed that serum LPL and GPIHBP1 concentrations were significantly higher in the participants with higher SMI. Spearman’s correlation analyses showed that SMI was positively correlated with LPL (ρ = 0.341, p < 0.001) and GPIHBP1 (ρ = 0.309, p = 0.001) concentration. The serum concentrations of LPL and GPIHBP1 were also inversely correlated with serum concentrations of triglyceride (LPL, ρ = − 0.198, p = 0.037; GPIHBP1, ρ = − 0.249, p = 0.008). Serum HTGL concentration was positively correlated with serum concentrations of total cholesterol (ρ = 0.308, p = 0.001), low-density lipoprotein-cholesterol (ρ = 0.336, p < 0.001), and free 3,5,3′-triiodothyronine (ρ = 0.260, p = 0.006), but not with SMI.

Conclusions

The results suggest that increased skeletal muscle mass leads to improvements in energy metabolism by promoting triglyceride-rich lipoprotein hydrolysis through the increase in circulating LPL and GPIHBP1.

Serum Triglyceride Lipase Concentrations are Independent Risk Factors for Coronary Artery Disease and In-Stent Restenosis

Aim: Endothelial lipase (EL), hepatic lipase (HL), and lipoprotein lipase (LPL) are all triglyceride lipases and are associated with coronary artery disease (CAD). However, whether they can be simultaneous independent risk factors for CAD is unknown. In the present study, we investigated whether the three lipases can be independent risk factors simultaneously for CAD and whether combining these lipases could provide greater predictive power than high-density lipoprotein cholesterol (HDL-c) for the development of CAD.

Methods: Eighty-six patients with CAD and 65 healthy controls were enrolled in the study. Additionally, 38 patients who underwent one-year follow-up angiography after percutaneous coronary intervention with stent implantation were collected to investigate in-stent restenosis. Serum EL, HL, and LPL concentrations were measured and compared with other coronary risk factors.

Results: Serum EL and HL concentrations were both significantly increased in patients with CAD or in-stent restenosis, whereas serum LPL concentration was reduced significantly in patients with CAD. Multivariate logistic regression analysis indicated that the three lipases were simultaneous independent risk factors for CAD. However, only serum EL concentration was considered an independent risk factor for in-stent restenosis. Importantly, the receiver operating characteristic curve showed that the combined measurement of the three lipases displayed better predictive power than HDL-c or any one of the three lipases for CAD.

Conclusions: Serum EL concentration was an independent risk factor for both CAD and in-stent restenosis. Moreover, the combined assessment of serum EL, HL, and LPL concentrations as multiple risk factors provided potent predictive power for CAD.

Standing is not enough: A randomized crossover study on the acute cardiometabolic effects of variations in sitting in healthy young men

OBJECTIVES

Standing desks and stability balls are increasingly popular to increase muscle activity and thereby prevent potential adverse cardiometabolic effects of prolonged sitting. The present study examined the effects of (1) sitting on a stability ball ('active sitting') and (2) hourly 10-min standing interruptions during prolonged sitting on postprandial cardiometabolic biomarkers.

DESIGN

Experimental crossover study.

METHODS

Twenty healthy-weight males (19.2±0.6years) participated randomly in three 5-h conditions: (1) sitting on an office chair (SIT), (2) sitting on a stability ball (SIT-ACTIVE) and (3) sitting with hourly 10-min standing interruptions (SIT-STAND). In each condition, participants consumed a standardized mixed meal at baseline. Hourly blood samples and pre/post saliva samples were collected and analyzed for levels of insulin, glucose and cortisol. Pre/post hemodynamic monitoring (middle finger; Nexfin-monitoring) was conducted; heart rate was measured continuously (Polar) and muscle activity (leg and lower-back, Portilab) was measured during periods of sitting (on an office chair and on a stability ball) and standing.

RESULTS

Muscle activity and heart rate during standing periods were significantly higher than during sitting (both SIT and SIT-ACTIVE). Generalized estimating equations revealed no significant difference in any of the biomarkers between the three experimental conditions. Systolic blood pressure was lower during SIT-STAND, while stroke volume was lower during SIT-ACTIVE than during SIT. Although significant, these differences were small, approximating the day-to-day variability in blood pressure and stroke volume.

CONCLUSIONS

We conclude that hourly standing interruptions during 5h prolonged sitting or continuously sitting on a stability ball do not significantly affect postprandial cardiometabolic biomarkers in healthy young men.

TRIAL REGISTRATION

This trial is registered in the NTR trial register (NTRcode 5723).

Laparoscopic Sleeve Gastrectomy Significantly Increases Serum Lipoprotein Lipase Level in Obese Patients

OBJECTIVES

Obesity is one of the causes of metabolic disorders. Laparoscopic sleeve gastrectomy (LSG) confers beneficial effects not only on body weight (BW) but also on metabolic disorders. The lipoprotein lipase (LPL) level in preheparin serum is associated with visceral adipose tissue and reflects insulin resistance. However, the change in serum preheparin LPL levels after LSG remains unclear. This study aimed to examine the effect of LSG on preheparin LPL level in obese patients compared with nonsurgical treatment.

METHODS

We retrospectively reviewed a total of 100 obese patients who were treated for obesity and had preheparin LPL levels measured before and 12 months after LSG or after 12 months of nonsurgical treatment. Fifty-six patients received LSG (LSG group), and 44 patients had no surgical treatment (nonsurgical group). We compared clinical parameters such as body mass index (BMI), hemoglobin A1c (HbA1c), and preheparin LPL level before and 12 months after treatment.

RESULTS

BMI and HbA1c decreased significantly in both groups, but decreases in both parameters were greater in the LSG group than in the nonsurgical group. Estimated glomerular filtration was significantly improved only in the LSG group. Preheparin LPL level increased significantly only in the LSG group (from 45.8 ± 21.6 to 75.0 ± 34.9 ng/mL, p < 0.001). Multiple regression identified LSG and decreased BMI as independent predictors of preheparin LPL level increase.

CONCLUSIONS

These results suggest that LSG independently increases pre-heparin LPL level beyond BW reduction in obese patients.

Daily sitting time associated with the risk of metabolic syndrome in Korean adolescents

BACKGROUND

This study aimed to investigate the relationship between daily sitting time and the risk of metabolic syndrome in Korean adolescents.

METHODS

Data from 486 adolescents aged 12-18 years were obtained from national surveys. Daily sitting time was measured using questionnaires and divided into three intervals: <8 h; 8-12 h; and ≥12 h.

RESULTS

The mean daily sitting time and prevalence of positive metabolic components were 620.9±9.9 min/day and 45.5±2.7%, respectively. In a multivariate logistic regression analysis, adolescents who sat longer were more likely to have metabolic components (p<0.05), independent of age, sex, area of residence, sleeping time and body mass index.

CONCLUSIONS

Longer daily sitting time appears to be associated with an increased risk of metabolic syndrome in adolescents. These findings highlight the need to focus on reducing sitting time for all adolescents, not just for those at risk of obesity.

The role of plasma lipoprotein lipase, hepatic lipase and GPIHBP1 in the metabolism of remnant lipoproteins and small dense LDL in patients with coronary artery disease

BACKGROUND

The relationship between plasma lipoprotein lipase (LPL), hepatic triglyceride lipase (HTGL), glycosylphosphatidylinositol anchored HDL binding protein1 (GPIHBP1) concentration and the metabolism of remnant lipoproteins (RLP) and small dense LDL (sdLDL) in patients with coronary artery disease (CAD) is not fully elucidated.

METHODS

One hundred patients who underwent coronary angiography were enrolled. The plasma LPL, HTGL and GPIHBP1 concentrations were determined by ELISA. The time dependent changes in those lipases, lipids and lipoproteins were studied at a time-point just before, and 15min, 4h and 24h after heparin administration.

RESULTS

The LPL concentration exhibited a significant positive correlation with HDL-C, and inversely correlated with TG and RLP-C. The HTGL concentration was positively correlated with RLP-C and sdLDL-C. The HTGL ratio of the pre-heparin/post-heparin plasma concentration and sdLDL-C/LDL-C ratio were significantly greater in CAD patients than in non-CAD patients. GPIHBP1 was positively correlated with LPL and inversely correlated with RLP-C and sdLDL-C.

CONCLUSION

The HTGL concentration was positively correlated with RLP-C and sdLDL-C, while LPL and GPIHBP1 were inversely correlated with RLP-C and sdLDL-C. These results suggest that elevated HTGL is associated with increased CAD risk, while elevated LPL is associated with a reduction of CAD risk.

The effect of combined diet and exercise intervention on body weight and the serum GPIHBP1 concentration in overweight/obese middle-aged women

BACKGROUND

The relationship between the effects of diet and exercise intervention and the body weight associated with the serum lipoprotein lipase (LPL), hepatic triglyceride lipase (HTGL) and glycosylphosphatidylinositol anchored high density lipoprotein binding protein 1 (GPIHBP1) concentrations has not been elucidated.

METHODS

Sixty-six overweight/obese middle aged women were assigned to the diet and exercise intervention for 4months. They were divided into 2 groups followed by the body mass index (BMI) decreased >3% (n=41) and <3% (n=25). Serum lipids, lipoproteins and the LPL, HTGL, GPIHBP1 concentrations were determined.

RESULTS

The cases in which the BMI decreased >3% exhibited significant improvement of diagnostic markers compared with the cases with <3% decrease after the intervention. The LPL concentration did not significantly change, but GPIHBP1 increased significantly after the intervention. The increased GPIHBP1 was significantly associated with decreased body weight. Multiple regression analysis indicated a strong association between GPIHBP1 and percentage of body fat.

CONCLUSIONS

The diet and exercise intervention significantly increased the serum GPIHBP1 concentration in association with a decrease in body weight and percentage of body fat. These results suggest that GPIHBP1 is a better marker for body weight decrease than LPL.

The heterozygous N291S mutation in the lipoprotein lipase gene impairs whole-body insulin sensitivity and affects a distinct set of plasma metabolites in humans

BACKGROUND

Mutations in the lipoprotein lipase gene causing decreased lipoprotein lipase activity are associated with surrogate markers of insulin resistance and the metabolic syndrome in humans.

OBJECTIVE

We investigated the hypothesis that a heterozygous lipoprotein lipase mutation (N291S) induces whole-body insulin resistance and alterations in the plasma metabolome.

METHODS

In 6 carriers of a heterozygous lipoprotein lipase mutation (N291S) and 11 age-matched and weight-matched healthy controls, we examined insulin sensitivity and substrate metabolism by euglycemic-hyperinsulinemic clamps combined with indirect calorimetry. Plasma samples were taken before and after the clamp (4 hours of physiological hyperinsulinemia), and metabolites were measured enzymatically or by gas chromatography-mass spectrometry.

RESULTS

Compared with healthy controls, heterozygous carriers of a defective lipoprotein lipase allele had elevated fasting plasma levels triglycerides (P < .006), and markedly impaired insulin-stimulated glucose disposal rates (P < .024) and nonoxidative glucose metabolism (P < .015). Plasma metabolite profiling demonstrated lower circulating levels of pyruvic acid and α-tocopherol in the N291S carriers than in controls both before and after stimulation with insulin (all >1.5-fold change and P < .05).

CONCLUSION

Heterozygous carriers with a defective lipoprotein lipase allele are less insulin sensitive and have increased plasma levels of nonesterified fatty acids and triglycerides. The heterozygous N291S carriers also have a distinct plasma metabolomic signature, which may serve as a diagnostic tool for deficient lipoprotein lipase activity and as a marker of lipid-induced insulin resistance.

ADIPOQ single nucleotide polymorphism: Association with adiponectin and lipoproteins levels restricted to men

Adiponectin is an adipokine inversely correlated with obesity, which has beneficial effect on insulin resistance and lipid metabolism. Considering its potential as a therapeutic target in the metabolic disorder contexts, and in order to add knowledge in the area, our study evaluated the ADIPOQ 276G > T polymorphism effect on adiponectin levels, and on lipoproteins of clinical interest in a population sample composed of 211 healthy individuals. Significant effects were observed only among men: the carriers of heterozygous genotype (GT) showed high levels of adiponectin (p = 0.018), while the rare homozygous genotype (TT) gave its carriers a negative phenotype, represented by higher levels of low density lipoprotein cholesterol (LDL-C) (p = 0.004 and p = 0.005) and total cholesterol (TC) (p = 0.010 and p = 0.005) compared to carriers of other genotypes (GG and GT respectively), the independent effect of SNP on LDL-C and TC levels was confirmed by multiple regression analysis (p = 0.008 and p = 0.044). We found no evidence of correlation between circulating adiponectin levels and biochemical markers, which suggests, therefore, an SNP 276G > T independent effect on adiponectin levels and on lipoprotein metabolism in men enrolled in this study.

Hepatic Lipase: a Comprehensive View of its Role on Plasma Lipid and Lipoprotein Metabolism

Hepatic lipase (HL) is a key enzyme catalyzing the hydrolysis of triglycerides (TG) and phospholipids (PLs) in several lipoproteins. It is generally recognized that HL is involved in the remodeling of remnant, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and the production of small, dense low-density lipoproteins (sd-LDLs).On the other hand, it is unclear whether HL accelerates or retards atherosclerosis. From the clinical point of view, HL deficiency may provide useful information on answering this question, but the rarity of this disease makes it impossible to conduct epidemiological study.In this review, we describe a comprehensive and updated view of the clinical significance of HL on lipid and lipoprotein metabolism.

Relationships among serum lipoprotein lipase mass, visceral fat, and retinal nerve fiber layer thickness

PURPOSE

The purpose of the study was to determine whether there were significant correlations among the serum lipoprotein lipase mass, visceral fat, and the retinal nerve fiber layer (RNFL) thickness.

METHODS

We studied 118 consecutive subjects. Optical coherence tomography (OCT) was used to measure the RNFL thickness. The Pearson correlation coefficient was used to determine the relationships among lipoprotein lipase (LPL) mass, visceral fat area by computed tomography, OCT, and other parameters. We performed a multiple regression analysis to identify independent factors for the RNFL sectors that were the most strongly correlated with the LPL mass and visceral fat area.

RESULTS

The LPL mass was significantly correlated with the nasal RNFL thickness in both eyes (right eye: r = 0.24, p = 0.008, left eye: 0.32, 0.0008) and inferior RNFL thickness in the left eye ( r = 0.23, p = 0.01). The visceral fat area was significantly correlated with the nasal RNFL thickness in both eyes (right eye: r = -0.19, p = 0.04, left eye: -0.30, 0.0008) and the inferior RNFL thickness in the left eye ( r = -0.23, p = 0.01). The subcutaneous fat area was not significantly correlated with any OCT parameters. The multiple regression analysis revealed that age, LPL mass, and visceral fat area were independent contributors to the nasal RNFL thickness in the left eye (age, standard regression coefficient = -0.34 , p = 0.0004; LPL mass, 0.26, 2.49, 0.01; visceral fat area, -0.21, 0.03).

CONCLUSION

A reduction of lipoprotein lipase and accumulation of visceral fat might produce retinal neurodegenerative disorders that decrease the RNFL thickness, especially on the nasal side.

Effects of body weight reduction on cardio-ankle vascular index (CAVI)

OBJECTIVE

Obesity is associated with type 2 diabetes, dyslipidemia and hypertension, contributing to atherogenesis. Weight reduction is the fundamental therapy for obesity. Recently, a novel arterial stiffness parameter called cardio-ankle vascular index (CAVI) has been developed. We hypothesized that CAVI may be a candidate marker of increased vascular stiffness in obese patients. The aim of this study is to investigate the effect of weight reduction on CAVI.

SUBJECTS AND METHODS

Using CAVI as an indicator, we assessed the changes in arterial stiffness in 47 obese Japanese subjects (aged 46 ± 13 years) who underwent a 12-week weight reduction program consisting of a calorie restriction diet (20-25 kcal/day) and exercise therapy. Visceral fat area (VFA) was evaluated by CT.

RESULTS

At baseline, CAVI correlated positively with age (r = 0.70), blood pressure (r = 0.23), VFA (r = 0.26) and HbA1c (r = 0.39). After 12 weeks of weight reduction, mean BMI decreased from 33.3 ± 7.5 to 30.7 ± 6.4 kg/m(2) (p < 0.0001), and mean CAVI decreased from 8.3 to 7.9 (p < 0.01). The change in VFA correlated positively with change in CAVI in subjects with decrease in CAVI (r = 0.47). Furthermore, change in VFA was a significant independent predictor for change in CAVI. No significant correlation was observed between change in CAVI and clinical variables such as BMI, HbA1c and lipids.

CONCLUSION

This study demonstrated that CAVI decreased after weight reduction, and was associated with a decrease in VFA. CAVI reduction maybe a marker of improved vascular stiffness after weight reduction in subjects with visceral adiposity.

Utility of the triglyceride level for predicting incident diabetes mellitus according to the fasting status and body mass index category: the Ibaraki Prefectural Health Study

AIM

The levels of lipids, especially triglycerides (TG), and obesity are associated with diabetes mellitus (DM). Although typically measured in fasting individuals, non-fasting lipid measurements play an important role in predicting future DM. This study compared the predictive efficacy of lipid variables according to the fasting status and body mass index (BMI) category.

METHODS

Data were collected for 39,196 nondiabetic men and 87,980 nondiabetic women 40-79years of age who underwent health checkups in Ibaraki-Prefecture, Japan in 1993 and were followed through 2007. The hazard ratios (HRs) for DM in relation to sex, the fasting status and BMI were estimated using a Cox proportional hazards model.

RESULTS

A total of 8,867 participants, 4,012 men and 4,855 women, developed DM during a mean follow-up of 5.5 years. TG was found to be an independent predictor of incident DM in both fasting and non-fasting men and non-fasting women. The multivariable-adjusted HR for DM according to the TG quartile (Q) 4 vs. Q1 was 1.18 (95% confidence interval (CI): 1.05, 1.34) in the non-fasting men with a normal BMI (18.5-24.9). This trend was also observed in the non-fasting women with a normal BMI. That is, the multivariable-adjusted HRs for DM for TG Q2, Q3 and Q4 compared with Q1 were 1.07 (95% CI: 0.94, 1.23), 1.17 (95%CI: 1.03, 1.34) and 1.48 (95%CI: 1.30, 1.69), respectively.

CONCLUSIONS

The fasting and non-fasting TG levels in men and non-fasting TG levels in women are predictive of future DM among those with a normal BMI. Clinicians must pay attention to those individuals at high risk for DM.

Role of SN1 lipases on plasma lipids in metabolic syndrome and obesity

OBJECTIVE

To assess the phospholipase activity of endothelial (EL) and hepatic lipase (HL) in postheparin plasma of subjects with metabolic syndrome (MS)/obesity and their relationship with atherogenic and antiatherogenic lipoproteins. Additionally, to evaluate lipoprotein lipase (LPL) and HL activity as triglyceride (TG)-hydrolyses to complete the analyses of SN1 lipolytic enzymes in the same patient.

APPROACH AND RESULTS

Plasma EL, HL, and LPL activities were evaluated in 59 patients with MS and 36 controls. A trend toward higher EL activity was observed in MS. EL activity was increased in obese compared with normal weight group (P=0.009) and was negatively associated with high-density lipoprotein-cholesterol (P=0.014 and P=0.005) and apolipoprotein A-I (P=0.045 and P=0.001) in control and MS group, respectively. HL activity, as TG-hydrolase, was increased in MS (P=0.025) as well as in obese group (P=0.017); directly correlated with low-density lipoprotein-cholesterol (P=0.005) and apolipoprotein B (P=0.003) and negatively with high-density lipoprotein-cholesterol (P=0.021) in control group. LPL was decreased in MS (P<0.001) as well as in overweight and obese compared with normal weight group (P=0.015 and P=0.004, respectively); inversely correlated %TG-very low-density lipoproteins (P=0.04) and TG/apolipoprotein B index (P=0.013) in control group. These associations were not found in MS.

CONCLUSIONS

We describe for the first time EL and HL activity as phospholipases in MS/obesity, being both responsible for high-density lipoprotein catabolism. Our results elucidate part of the remaining controversies about SN1 lipases activity in MS and different grades of obesity. The impact of insulin resistance on the activity of the 3 enzymes determines the lipoprotein alterations observed in these states.

Pioglitazone improves the cardio-ankle vascular index in patients with type 2 diabetes mellitus treated with metformin

BACKGROUND

Type 2 diabetes is known to be associated with elevated cardiovascular mortality. Pioglitazone improves blood pressure (BP) and pulse wave velocity (PWV), which is an arterial stiffness parameter. Arterial stiffness is closely associated with cardiovascular disease. However, PWV is correlated with BP. The cardio-ankle vascular index (CAVI) reflects arterial stiffness independent of BP. Pioglitazone improves PWV but reduces blood pressure. The aim of this study was to re-evaluate the effect of pioglitazone on arterial stiffness with CAVI.

METHODS

Sixty patients with type 2 diabetes mellitus and already on 500 mg/day of metformin received add-on therapy of pioglitazone 15 mg/day or glimepiride 1 mg/day for 6 months, during which time changes in their metabolic parameters and CAVI were observed.

RESULTS

After 6 months of treatment, both pioglitazone (n=30) and glimepiride (n=30) improved fasting blood glucose and glycated hemoglobin. The changes in fasting blood glucose and glycated hemoglobin between the two groups were greater in the pioglitazone group. Systolic and diastolic BP was decreased in both groups, with no significant between-group differences. Only pioglitazone increased serum adiponectin levels, and the change in adiponectin between the pioglitazone and glimepiride groups was significantly different. CAVI was decreased significantly by pioglitazone but remained unchanged after treatment with glimepiride. The change in CAVI between the two groups was significantly different.

CONCLUSION

These results suggest that pioglitazone improves CAVI, a BP-independent arterial stiffness parameter, in patients with type 2 diabetes mellitus treated with metformin.

Comparative effects of pioglitazone and metformin on oxidative stress markers in newly diagnosed type 2 diabetes patients: a randomized clinical trial

AIMS

Recent studies have suggested that pioglitazone exerts anti-oxidant properties which may countervail oxidative stress (OS). We aimed to elucidate the effects of pioglitazone on OS modulation and to compare its effects with metformin.

METHODS

Data from the randomized clinical trial (registration no.NCT01521624) were used. Newly diagnosed type 2 diabetes patients were assigned to pioglitazone 30mg daily (n=30), metformin 1000mg daily (n=50), or no medication (n=49). Recommendations for exercise and dietary modifications were provided for three groups. Serum concentrations of advanced oxidation protein products(AOPP), advanced glycation end products(AGE), ferritin reducing ability of plasma(FRAP), and enzymatic activities of paraoxonase(PON), lecithin-cholesterol asyltransferase(LCAT), and lipoprotein lipase(LPL) were measured at baseline and after three months.

RESULTS

In comparison with no medication, pioglitazone proved to be superior in OS amelioration (p<0.05 in all analyses). Compared with metformin, both medications were equally effective in decrement of AOPP and AGE, along with increment of PON (p=0.688, 0.140, and 0.273, respectively). FRAP concentrations increased significantly with metformin (p=0.012). On the other hand, pioglitazone yielded better efficacy in restoration of LCAT and LPL enzymatic activities (p=0.037, and <0.001, respectively).

CONCLUSIONS

Similar to metformin, three months treatment with Pioglitazone is beneficial in terms of OS alleviation and anti-oxidant capacity restoration.

Fasting apolipoprotein B48 is a marker for peripheral arterial disease in type 2 diabetes

An earlier study showed that fasting and postprandial concentrations of apolipoprotein B48 were raised in patients with type 2 diabetes (DM2) and peripheral arterial disease (PAD) as compared with persons without DM2 or persons with DM2 but not PAD. The aim of this study was to confirm the association of PAD and B48 in a larger group of patients with DM2 and the relation of B48 with the preheparin lipoprotein lipase (LPL) mass. We studied 456 patients with DM2. PAD was defined as an ankle-brachial index (ABI) <0.9. Apolipoprotein B48 was quantified by ELISA. Apo B48 was significantly higher in the group with an ABI <0.9 than the groups with ABI of 0.9-1.3 and >1.3 (10.7 ± 6.28 vs. 9.24 ± 5.5 vs. 9.17 ± 8.8 mg/L, ANOVA test, p < 0.05). B48 was independently associated with an ABI <0.9 (OR 1.053; 95 % CI, 1.013-1.094; p < 0.05), together with smoking and duration of diabetes. The preheparin LPL mass was similar in the patients with and without PAD. In conclusion, we confirmed that fasting B48 is an independent marker of PAD in patients with DM2, unrelated to the preheparin LPL mass, statin therapy or glucose lowering treatment.

Maternal obesity is associated with the formation of small dense LDL and hypoadiponectinemia in the third trimester

CONTEXT

Maternal obesity is associated with high plasma triglyceride, poor vascular function, and an increased risk for pregnancy complications. In normal-weight pregnant women, higher triglyceride is associated with increased small, dense low-density lipoprotein (LDL).

HYPOTHESIS

In obese pregnancy, increased plasma triglyceride concentrations result in triglyceride enrichment of very low-density lipoprotein-1 particles and formation of small dense LDL via lipoprotein lipase.

DESIGN

Women (n = 55) of body mass index of 18-46 kg/m(2) were sampled longitudinally at 12, 26, and 35 weeks' gestation and 4 months postnatally.

SETTING

Women were recruited at hospital antenatal appointments, and study visits were in a clinical research suite.

OUTCOME MEASURES

Plasma concentrations of lipids, triglyceride-rich lipoproteins, lipoprotein lipase mass, estradiol, steroid hormone binding globulin, insulin, glucose, leptin, and adiponectin were determined.

RESULTS

Obese women commenced pregnancy with higher plasma triglyceride, reached the same maximum, and then returned to higher postnatal levels than normal-weight women. Estradiol response to pregnancy (trimester 1-3 incremental area under the curve) was positively associated with plasma triglyceride response (r(2) adjusted 25%, P < .001). In the third trimester, the proportion of small, dense LDL was 2-fold higher in obese women than normal-weight women [mean (SD) 40.7 (18.8) vs 21.9 (10.9)%, P = .014], and 35% of obese, 14% of overweight, and none of the normal-weight women displayed an atherogenic LDL subfraction phenotype. The small, dense LDL mass response to pregnancy was inversely associated with adiponectin response (17%, P = .013).

CONCLUSIONS

Maternal obesity is associated with an atherogenic LDL subfraction phenotype and may provide a mechanistic link to poor vascular function and adverse pregnancy outcome.

Associations between sedentary behaviour and metabolic parameters in patients with schizophrenia

This study examined the association between sedentary behaviour and metabolic parameters among patients with schizophrenia. A total of 76 patients and 38 healthy age-, gender- and BMI-matched volunteers were included. Participants were asked for their overall sitting and physical activity behaviour using the International Physical Activity Questionnaire. Patients were additionally screened for psychiatric symptoms and extrapyramidal side-effects of antipsychotic medication. On average, patients with schizophrenia spent 8.5h per day sitting (versus 6.21h in healthy controls). Patients sitting more than 10.4h per day had a higher BMI, waist circumference and fasting glucose concentrations and experienced more negative and cognitive symptoms than those sitting less than 5.8h per day. Overall sitting time was associated with a significantly greater likelihood of metabolic syndrome. A stepwise backward-elimination multivariate regression analysis demonstrated that sitting time is a significant predictor for BMI. Current results suggest patients with schizophrenia may benefit from reducing total sitting time.

The association of lipoprotein lipase PvuII polymorphism and niacin intake in the prevalence of metabolic syndrome: a KMSRI-Seoul study

Lipoprotein lipase (LPL) polymorphism correlated with LPL activity is associated with plasma lipid and lipoprotein levels. We aimed to investigate the frequency of LPL PvuII polymorphism and effects of LPL PvuII polymorphism and niacin intake on the prevalence of metabolic syndrome (MetSyn) in Koreans. Lifestyle questionnaires, anthropometry, and dietary records were completed, and LPL PvuII polymorphism, LPL mass, and lipid profiles were determined in 548 Koreans (MetSyn: 278, Non-MetSyn: 270). The MetSyn group showed a significantly lower frequency of P1P1 (wild type) and a higher frequency of P1P2 (hetero type) than the non-MetSyn group. The P2P2 (mutant type) group significantly showed lower levels of HDLc and LPL mass and a higher level of TG than the P1P1 group. As niacin intake increased, LPL mass decreased in the P2P2 group (r (2) = 0.07). In particular, the lowest niacin intake group (≤14.82 mg/day) increased more than 3 times with regard to a higher risk of MetSyn than the others in the P2P2 mutant groups. However, the MetSyn risk declined 74% at the optimal levels of niacin intake (14.83-17.80 mg/day) in the P2P2 group compared to those of the P1 allele group. The findings indicate that optimal levels of niacin intake effectively decreased Korean MetSyn prevalence in the P2P2 mutant group.

Associations between television viewing time and overall sitting time with the metabolic syndrome in older men and women: the Australian Diabetes, Obesity and Lifestyle study

OBJECTIVES

To examine associations between self-reported television (TV) viewing time and overall sitting time with the metabolic syndrome and its components.

DESIGN

Cross-sectional.

SETTING

Population-based sample of older men and women living in Australia.

PARTICIPANTS

One thousand nine hundred fifty-eight participants from the Australian Diabetes, Obesity and Lifestyle (AusDiab) study (aged ≥ 60, mean age 69, 54% women).

MEASUREMENTS

Self-reported television viewing time and overall sitting time were collected using an interviewer-administered questionnaire. The metabolic syndrome was defined according to the revised International Diabetes Federation criteria.

RESULTS

Compared with those in the lowest quartile, the odds ratios (ORs) of the metabolic syndrome in the highest quartile of television viewing time were 1.42 (95% confidence interval (CI)=0.93-2.15) for men and 1.42 (95% CI=1.01-2.01) for women and in the highest quartile of overall sitting time were 1.57 (95% CI=1.02-2.41) for men and 1.56 (95% CI=1.09-2.24) for women. Television viewing time was associated with lower high-density lipoprotein cholesterol (HDL-C) levels and glucose intolerance in women. Overall sitting time was detrimentally associated with greater risk of high triglyceride levels in men and women, abdominal obesity in women, and low HDL-C levels in men. All models were adjusted for age, education, physical activity, self-rated health, employment, diet, smoking, and alcohol intake and for hormone replacement therapy and estrogen use in women.

CONCLUSION

For older adults, high levels of sedentary behavior were associated with greater prevalence of the metabolic syndrome; reducing prolonged overall sitting time may be a feasible way to improve metabolic health.

The HindIII polymorphism in the lipoprotein lipase gene predicts type 2 diabetes risk among Chinese adults

OBJECTIVE

We aimed to investigate the polymorphism HindIII of the lipoprotein lipase (LPL) gene to explore whether it had a potential role in susceptibility to type 2 diabetes mellitus (T2DM) among Han Chinese, and whether this effect was influenced by regulating LPL or other risk factors.

METHODS

Overall, 654 Han Chinese adults were selected from a community-based cross-sectional study using a stratified cluster random sampling. Genotyping was performed using the PCR-RFLP technique, and the metabolic variables were measured using standard methods.

RESULTS

Individuals with the HindIII H-/H- genotype tended to have higher pre-heparin LPL (PrLPL) and lower triglyceride levels but an unexpected higher prevalence of T2DM compared with the H+/H+ genotype carriers. The association between the H-/H- genotype and T2DM risk remained unchanged across all subgroups of lipids/glucose-related RF. In a recessive model, the H-/H- genotype conferred a 2.12-fold increased risk [odds ratio (OR): 3.12; 95% confidence interval (CI): 1.18-8.27] for T2DM after controlling for age and sex, and increased further after additionally adjusting for traditional RFs, and PrLPL (OR=4.45; 95% CI=1.51-13.07).

CONCLUSIONS

This study indicated that Chinese adults with the LPL gene HindIII H-/H- genotype had a significantly increased risk of T2DM, even if they had favorable lipid profiles.

Improvement of cardio-ankle vascular index by glimepiride in type 2 diabetic patients

AIMS

Glimepiride, a third generation sulfonylurea (SU), is known to have extrapancreatic effects, but its vascular effect is unclear. We investigated the efficacy of glimepiride in improving arterial stiffness assessed by cardio-ankle vascular index (CAVI) in type 2 diabetic patients, compared with glibenclamide, a conventional SU.

METHODS

Forty type 2 diabetic patients were randomly assigned to two groups. One group was administered glimepiride 1.5 mg/day, and the other group was administered glibenclamide 1.25 mg/day for 6 months.

RESULTS

No significant difference in hypoglycaemic effect was observed between two groups. CAVI significantly decreased only in glimepiride group (9.4 ± 1.4→8.9 ± 0.8, p < 0.05). Decrease in CAVI was greater in glimepiride group than in glibenclamide group (-0.50 ± 0.98 vs. -0.04 ± 0.57, p = 0.048). Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) decreased in glimepiride group and increased in glibenclamide group, and the changes were significantly different between groups (-1.5 ± 3.5 vs. + 1.8 ± 3.6, p = 0.009); whereas serum lipoprotein lipase mass increased in glibenclamide group and decreased in glibenclamide group, and the changes tended to be different between groups (+ 2.1 ± 19.1 vs. -7.4 ± 19.2, p = 0.096). Change in urinary 8-OHdG was a significant independent predictor for change in CAVI in all subjects.

CONCLUSIONS

These results suggest that glimepiride improves CAVI compared with glibenclamide. Reduced oxidative stress and improved insulin resistance may contribute to the improvement of CAVI by glimerpiride.

Triglyceride lipases and atherosclerosis

PURPOSE OF REVIEW

There are strong epidemiologic connections between plasma triglycerides and atherosclerosis. We will consider to what extent this goes back to derangements of the lipoprotein lipase (LPL) system. The roles of hepatic lipase and endothelial lipase will also be touched upon.

RECENT FINDINGS

Understanding of LPL action has taken major steps with the discovery of lipase maturation factor 1 as a specific endoplasmic reticulum chaperon needed for proper folding of the lipases, glycosylphosphatidylinositol-anchored HDL-binding protein 1 as an endothelial cell protein needed for transport and binding of LPL and some angiopoietin-like proteins that can modulate LPL activity. Studies of genetic variants continue to support the important roles of the lipases in lipoprotein metabolism and in atherosclerosis.

CONCLUSION

There are several ways by which derangement of the lipases may contribute to atherogenesis. Lipase actions are major determinants of plasma lipoprotein patterns. LPL activity must be modulated in relation to the physiological situation (feeding, fasting, exercise, etc.). Fatty acids and monoglycerides generated must be efficiently removed so that they do not endanger the integrity of the endothelium, cause lipotoxic reactions or both. In addition, the lipases may cause binding and endocytosis of lipoprotein particles in the artery wall.

Visceral fat accumulation in Japanese high school students and related atherosclerotic risk factors

AIM

To investigate the factors that influence visceral fat accumulation in adolescence, we performed a medical examination of high school students and assessed abdominal fat thickness and fatty change of the liver.

METHODS

A cohort of 374 Japanese high school students aged 15-16 years (193 boys and 181 girls) in public high schools in Chiba prefecture were enrolled. Anthropometric parameters, blood cell count, blood chemistry and adipocytokine levels were measured. Preperitoneal fat thickness (PFT) and echoic contrast of the liver were measured by ultrasonography.

RESULTS

Anthropometric parameters, systolic blood pressure, blood cell count, ALT, AST, FBS, gamma-GTP, HDL-C, LpL, UA, adiponectin, resistin and leptin levels differed between sexes. Multivariate regression analysis revealed that leptin was the most appropriate marker for PFT in both sexes (p<0.0001). Visceral obesity, categorized as PFT exceeding 8 mm, was observed in 9.6% of all students. Boys with visceral obesity showed apparent liver dysfunction, hyperlipidemia, hyperinsulinemia, and high leptin and low adiponectin levels. Overall, 16.6% of boys and 30.4% of girls showed hepatorenal echo contrast positivity. Boys with visceral obesity and fatty liver had more risk factors for atherosclerosis.

CONCLUSIONS

Physical examination of high school students is important for early detection of atherosclerosis.

Release of 12 adipokines by adipose tissue, nonfat cells, and fat cells from obese women

The relative release in vitro of endothelin-1, zinc-alpha2-glycoprotein (ZAG), lipocalin-2, CD14, RANTES (regulated on activation, normal T cell expressed and secreted protein), lipoprotein lipase (LPL), osteoprotegerin (OPG), fatty acid-binding protein 4 (FABP-4), visfatin/PBEF/Nampt, glutathione peroxidase-3 (GPX-3), intracellular cell adhesion molecule 1 (ICAM-1), and amyloid A was examined using explants of human adipose tissue as well as the nonfat cell fractions and adipocytes from obese women. Over a 48-h incubation the majority of the release of LPL was by fat cells whereas that of lipocalin-2, RANTES, and ICAM-1 was by the nonfat cells present in human adipose tissue. In contrast appreciable amounts of OPG, amyloid A, ZAG, FABP-4, GPX-3, CD14, and visfatin/PBEF/Nampt were released by both fat cells and nonfat cells. There was an excellent correlation (r = 0.75) between the ratios of adipokine release by fat cells to nonfat cells over 48 h and the ratio of their mRNAs in fat cells to nonfat cells at the start of the incubation. The total release of ZAG, OPG, RANTES, and amyloid A by incubated adipose tissue explants from women with a fat mass of 65 kg was not different from that by women with a fat mass of 29 kg. In contrast that of ICAM-1, FABP-4, GPX-3, visfatin/PBEF/Nampt, CD14, lipocalin-2, LP, and endothelin-1 was significantly greater in tissue from women with a total fat mass of 65 kg.