Effects of sitagliptin therapy on markers of low-grade inflammation and cell adhesion molecules in patients with type 2 diabetes

Inflammation and endothelial dysfunction are increasingly being recognized as key etiological factors in the development of atherosclerosis and subsequent cardiovascular disease. These pro-atherogenic factors are strongly correlated and are often found to co-segregate in patients with type 2 diabetes. The impact of sitagliptin, a selective inhibitor of dipeptidyl peptidase-4, on inflammation and markers of endothelial function remains to be fully characterized.     

Bariatric surgery in morbidly obese patients improves the atherogenic qualitative properties of the plasma lipoproteins

Objective

The purpose of this study was to evaluate the effect of weight loss induced in morbidly obese subjects by Roux-en-Y gastric bypass bariatric surgery on the atherogenic features of their plasma lipoproteins.

Methods

Twenty-one morbidly obese subjects undergoing bariatric surgery were followed up for up to 1 year after surgery. Plasma and lipoproteins were assayed for chemical composition and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. Lipoprotein size was assessed by non-denaturing polyacrylamide gradient gel electrophoresis, and oxidised LDL by ELISA. Liver samples were assayed for mRNA abundance of oxidative markers.

Results

Lipid profile analysis revealed a reduction in the plasma concentrations of cholesterol and triglycerides, which were mainly associated with a significant reduction in the plasma concentration of circulating apoB-containing lipoproteins rather than with changes in their relative chemical composition. All patients displayed a pattern A phenotype of LDL subfractions and a relative increase in the antiatherogenic plasma HDL-2 subfraction (>2-fold; P < 0.001). The switch towards predominantly larger HDL particles was due to an increase in their relative cholesteryl ester content. Excess weight loss also led to a significant decrease in the plasma concentration of oxidised LDL (∼−25%; P < 0.01) and in the total Lp-PLA2 activity. Interestingly, the decrease in plasma Lp-PLA2 was mainly attributed to a decrease in the apoB-containing lipoprotein-bound Lp-PLA2.

Conclusion

Our data indicate that the weight loss induced by bariatric surgery ameliorates the atherogenicity of plasma lipoproteins by reducing the apoB-containing Lp-PLA2 activity and oxidised LDL, as well as increasing the HDL-2 subfraction.     

Evidence for an exclusive association of matrix metalloproteinase-9 with dysfunctional high-density lipoprotein: A novel finding

Objective

High-density lipoprotein is a heterogeneous class of lipoprotein with diverse antiatherogenic functions. However, these antiatherogenic properties of HDL can be compromised in atherosclerotic conditions. We have recently identified dysfunctionality in HDL even among healthy subjects, during systemic inflammation. This study was carried out with the objective of examining whether dysfunctional HDL is associated with pro-inflammatory proteins other than the acute phase proteins as reported earlier.

Methods

Serum HDL was isolated by three different methods-density gradient ultracentrifugation, PEG precipitation and electroelution. The antioxidant property of HDL was assessed as change in oxidation of LDL based on Dichloro-dihydro-fluorescein diacetate assay. HDL was subjected to gelatin zymography and western blot for assessment of MMP 9 activity.

Results

Dysfunctional HDL did not prevent the auto-oxidation of LDL. On the contrary the oxidation was enhanced. The zymogram data indicated enhanced MMP-9 activity selectively in dysfunctional HDL, irrespective of HDL isolation methods. This was confirmed by western blot of HDL probed with antibody specific to MMP 9. We also observed that dysfunctional HDL induced inflammatory response in monocyte/macrophages as evidenced by enhanced TNF-α and decreased IL-10 production. Further, invitro incubation of functional HDL with MMP-9 provided direct evidence for the association of MMP-9 with HDL and the role of MMP-9 in HDL dysfunction.

Conclusion

A remarkable finding in the present study is the previously unrecognized association of MMP-9 with dysfunctional HDL and its proinflammatory property, indicating a novel molecular connection that can enhance the risk of cardiovascular disease in subjects with dysfunctional HDL.     

The one year exercise and lifestyle intervention program KLAKS: Effects on anthropometric parameters,cardiometabolic risk factors and glycemic control in childhood obesity

Objective

Regular physical exercise within structured lifestyle programs may improve weight status and minimize metabolic risk factors in childhood obesity. The aim of this study was to evaluate the effect of the one-year combined physical exercise/lifestyle program KLAKS on anthropometric and metabolic parameters and glycemic control in childhood obesity.

Materials and Methods

142 overweight/obese (BMI > 90th percentile) candidates (7–18 years) were enrolled, 115 participants completed the program. Anthropometrics and biochemical parameters were obtained at beginning and completion. An oral glucose tolerance test (OGTT) was performed in a subgroup of participants. Course of glucose and insulin levels within OGTT was correlated with several parameters and is reported here for those who completed the program.

Results

The mean standard deviation scores (SDS) decreased significantly for BMI, waist circumference, waist-to-height ratio (WHtR) and percentage body fat (all p ≤ 0.01). Improved metabolic risk markers included mean glucose levels within an OGTT at follow-up compared to baseline (p < 0.0001) and HbA1c (p = 0.05) as well as indications of improvement for gamma-glutamyl-transferase and free fatty acids.

Conclusions

The one-year combined exercise/lifestyle program KLAKS significantly improves markers of obesity and glycemic control. Impaired cardiometabolic risk markers, even subclinical, are also favorably influenced by program participation.     

Glycation of human high density lipoprotein by methylglyoxal: Effect on HDL-paraoxonase activity

Objective

Methylglyoxal (MG), a reactive carbonyl compound formed primarily from triose phosphates, appears to be involved in the molecular mechanisms of diabetes, end-stage renal disease and neurodegenerative diseases. Methylglyoxal exerts several biological activities. Among these it promotes advanced glycation end products (AGEs), which are crucial in pathogenesis of human disease. Previous studies have demonstrated that MG reacts with proteins and compositional modifications reflect loss of biological activity. The aim of the study was to investigate the effect of in vitro MG-induced glycation on human high density lipoprotein (HDL) and on the activity of the enzyme paraoxonase-1 (PON1).

Methods

HDL was incubated in the absence or in the presence of MG (0.2 mmol/L and 1.0 mmol/L) (MG-HDL) for different times (3, 6, 24 h) at 37 ° C. We evaluated apoprotein compositional changes, in both control and MG treated HDL, using intrinsic fluorescence of tryptophan and monitoring the decrease of free amino groups. Furthermore we evaluated fluorescent advanced glycation end products (Ex = 370 nm, Em = 440 nm) and the activity of HDL-paraoxonase.

Results

We demonstrated that human HDL is susceptible to glycation by MG (0.2 mmol/L and 1 mmol/L). The decrease of free amino groups and of intrinsic fluorescence of tryptophan demonstrates HDL apoprotein modifications in HDL incubated with MG. The compositional changes are associated with a significant increase in fluorescent advanced glycation end products and with a significant decrease of paraoxonase-1 enzyme activity associated with the HDL surface.

Conclusions

HDL-associated paraoxonase is responsible for the anti-inflammatory and anti-oxidative properties of HDL and detoxification against homocysteine-thiolactone. Therefore, modifications of apoprotein composition and the decrease of paraoxonase-1 activity in MG-treated HDL could affect the protective effect exerted by HDL against oxidative damage and could contribute to complications in patients affected by diseases associated with aging and oxidative stress.     

Effect of Nicotinic acid/Laropiprant in the lipoprotein(a) concentration with regard to baseline lipoprotein(a) concentration and LPA genotype

Background

Lipoprotein(a) [Lp(a)] is a lipoprotein in which apolipoproteinB-100 is linked to apolipoprotein(a) [apo(a)]. Significant variation in Lp(a) concentration is specific to LPA gene, which codes for apo(a). Nicotinic acid (NA) is used for treatment of dyslipidemias, and the lowering effect of NA on Lp(a) has been previously reported.

Objective

To evaluate the Lp(a) lowering effect of 1 g/20 mg and 2 g/40 mg day of Nicotinic acid/Laropiprant in subjects with different baseline Lp(a) concentrations and depending on the LPA genotype.

Methods

In an open-label, 10-week study, 1 g/20 mg day of NA/Laropiprant for 4 weeks followed by 6 weeks of 2 g/40 mg day conducted at 3 centers in Spain, 82 subjects were enrolled. Patients were studied at baseline and at the end of both treatment periods and were enrolled in three groups: normal Lp(a) (< 50 mg/dL), high Lp(a) (50–120 mg/dL) and very high Lp(a) (> 120 mg/dL). The LPA genetic polymorphism was analyzed by a real-time PCR.

Results

There was a significant difference in LPA genotypes among Lp(a) concentration groups and an inverse and significant correlation between baseline Lp(a) concentration and LPA genotype was found (R = − 0.372, p < 0.001). There were a significant decrease in total cholesterol, triglycerides, LDL cholesterol, apo B and Lp(a), and a significant increase in HDL cholesterol after NA/Laropiprant treatment, without changes in BMI. However, there were no statistical differences in percentage variation of analyzed variables depending on LPA genotype.

Conclusion

LPA genotype is a major determinant of Lp(a) baseline concentration. However, the lipid lowering effect of NA is not related to LPA genotype.     

Effect of Renin–Angiotensin System Inhibition on Cardiovascular Events in Older Hypertensive Patients with Metabolic Syndrome

Objective

Metabolic syndrome (MetS) is associated with cardiovascular disease (CVD). Insulin resistance has been hypothesized as the underlying feature of MetS. Angiotensin converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) are widely used antihypertensives that may improve insulin sensitivity. The aim of the study is to evaluate the effect of ACEI/ARB on incident CVD events in older hypertensive patients with MetS.

Materials/Methods

We used the Cardiovascular Health Study, a prospective cohort study of individuals > 65 years of age to evaluate ACEI/ARB use and time to CVD events (including coronary and cerebrovascular events). The study included 777 subjects who had hypertension and ATP III-defined MetS, but free of CVD and diabetes at baseline. Cox regression models were used to evaluate the effect of ACEI/ARB as compared to other antihypertensives on the time to the first CVD events.

Results

ACEI/ARB use was associated with a decreased risk of CVD events (adjusted HR = 0.658, 95 % C.I. [0.436–0.993]) compared to other antihypertensives. When CVD endpoints were evaluated separately, use of ACEI/ARB was associated with lower rates of angioplasty and coronary events (HR of 0.129 and 0.530 respectively, with 95 % CI [0.017–0.952] and [0.321–0.875]).

Conclusions

ACEI/ARB use was associated with a lower risk of CVD events in older hypertensive patients with MetS, primarily due to a reduction in coronary events. The potential protective effect of ACEI/ARB on CVD events in older individuals with MetS will need further confirmation from prospective studies.     

单核细胞计数与高密度脂蛋白胆固醇比值评价老年急性心肌梗死患者冠状动脉介入术后ST段回落不良的观察

目的探讨单核细胞计数与高密度脂蛋白胆固醇比值(MHR)评价老年急性ST段抬高型心肌梗死(STEMI)患者经皮冠状动脉介入术(PCI)后ST段回落不良的临床意义。方法回顾性病例对照研究,收集2015年12月至2018年12月我院收治的接受直接PCI治疗的老年STEMI患者274例的临床资料,按术后心电图ST段回落情况分为ST段回落不良组79例和良好组195例,比较两组患者临床资料,采用Logistic回归分析MHR与ST段回落不良的关系,并绘制受试者工作特征(ROC)曲线分析MHR预测STEMI患者ST段回落不良临床价值。结果与ST段回落良好组患者比较,ST段回落不良组患者前壁心肌梗死、Killip分级≥2级比例高,胸痛到球囊扩张时间长,入院时肌酸激酶同工酶、N末端脑钠肽前体、超敏C反应蛋白、血糖、血尿酸、纤维蛋白原、三酰甘油、单核细胞计数高,高密度脂蛋白胆固醇、淋巴细胞计数较低(均P<0.05)。ST段回落不良组患者MHR为0.75±0.22,高于ST段回落良好组患者的0.48±0.19(t=9.831,P=0.001)。多元Logistic回归分析,MHR是老年STEMI患者PCI后ST段回落不良的独立危险因素(OR=1.950,95%CI:1.646~5.430,P=0.003)。ROC曲线显示,MHR预测STEMI患者ST段回落不良的曲线下面积为0.867,敏感度为79.72%,特异度为79.61%,最佳诊断值为0.64。结论MHR可能是老年STEMI患者PCI术后ST段回落不良独立危险因素,有良好的预测价值。     

Effects of dehydroepiandrosterone (DHEA) supplementation on the lipid profile: A systematic review and dose-response meta-analysis of randomized controlled trials

Background and aimsDehydroepiandrosterone (DHEA) supplementation has gained attention in individuals with adrenal insufficiency, and as a tool for increasing androgens and estrogens whereby is proposed to improve the accretion of muscle and bone mass. However, DHEA supplementation has demonstrated negative effects on the lipid profile and, thus, we aimed to analyze the body of evidence in this regard.Methods and resultsA systematic review and dose-response meta-analysis of randomized controlled trials (RCTs) was performed employing in Scopus, PubMed/Medline, Web of Science, Embase and Google Scholar, then including relevant articles that addressed the effects of DHEA supplementation on the lipid profile, up to February 2020. Combined findings were generated from 23 eligible articles. Hence, total cholesterol (TC) (weighted mean difference (WMD): −3.5 mg/dl, 95% confidence interval (CI): −8.5 to 1.6)), low-density lipoprotein-cholesterol (LDL-C) (WMD: 0.34 mg/dl, 95% CI: −3 to 3.7) and triglycerides (TG) levels (WMD: −2.85 mg/dl, 95% CI: −9.3 to 3.6) did not alter in DHEA group compared to the control, but HDL-C levels significantly reduced in DHEA group (WMD: −3.1 mg/dl, 95% CI: −4.9 to −1.3). In addition, a significant reduction in HDL-C values was observed in studies comprising women (WMD: −5.1 mg/dl, 95% CI: −7.2 to −3) but not in males (WMD: 0.13 mg/dl, 95% CI: −1.4 to 1.7).ConclusionsOverall, supplementation with DHEA did not change circulating values of TC, LDL-C and TG, whereas it may decrease HDL-C levels. Further long-term RCTs are required to investigate the effects of DHEA particularly on major adverse cardiac events.     

Myeloperoxidase gene polymorphism predicts fibrosis severity in women with hepatitis C

Oxidative stress plays an important role on liver fibrosis progression in the course of hepatitis C virus (HCV) infection. Myeloperoxidase (MPO) is an enzyme released by neutrophils and macrophages, responsible for generating hypochlorous acid and reactive oxygen species (ROS) that may lead to liver injury in HCV infection. On the other hand, antioxidant enzymes such as manganese superoxide dismutase (SOD) controls ROS-mediated damage. The aim of the present study was to investigate the influence of MPO G-463A and SOD2 Ala16Val polymorphisms in the severity of liver fibrosis in individuals with chronic HCV infection. The present study included 270 patients with chronic HCV recruited from the Gastrohepatology Service of the Oswaldo Cruz University Hospital/Liver Institute of Pernambuco (Recife, Northeastern Brazil). All patients underwent liver biopsy, which was classified according METAVIR score. The SNPs were determined by real-time PCR. After multivariate analysis adjustment, the GG genotype of MPO and the presence of metabolic syndrome were independently associated with fibrosis severity in women (P = 0.025 OR 2.25 CI 1.10–4.59 and P = 0.032 OR 2.32 CI 1.07–5.01, respectively). The presence of the GG genotype seems to be a risk factor for fibrosis severity in women with HCV.