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Concept: Cholesterol

477

It is well known that total cholesterol becomes less of a risk factor or not at all for all-cause and cardiovascular (CV) mortality with increasing age, but as little is known as to whether low-density lipoprotein cholesterol (LDL-C), one component of total cholesterol, is associated with mortality in the elderly, we decided to investigate this issue.

Concepts: Cholesterol, Atherosclerosis, Cardiovascular disease, Low-density lipoprotein, Atheroma, Niacin

470

Background Evolocumab is a monoclonal antibody that inhibits proprotein convertase subtilisin-kexin type 9 (PCSK9) and lowers low-density lipoprotein (LDL) cholesterol levels by approximately 60%. Whether it prevents cardiovascular events is uncertain. Methods We conducted a randomized, double-blind, placebo-controlled trial involving 27,564 patients with atherosclerotic cardiovascular disease and LDL cholesterol levels of 70 mg per deciliter (1.8 mmol per liter) or higher who were receiving statin therapy. Patients were randomly assigned to receive evolocumab (either 140 mg every 2 weeks or 420 mg monthly) or matching placebo as subcutaneous injections. The primary efficacy end point was the composite of cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina, or coronary revascularization. The key secondary efficacy end point was the composite of cardiovascular death, myocardial infarction, or stroke. The median duration of follow-up was 2.2 years. Results At 48 weeks, the least-squares mean percentage reduction in LDL cholesterol levels with evolocumab, as compared with placebo, was 59%, from a median baseline value of 92 mg per deciliter (2.4 mmol per liter) to 30 mg per deciliter (0.78 mmol per liter) (P<0.001). Relative to placebo, evolocumab treatment significantly reduced the risk of the primary end point (1344 patients [9.8%] vs. 1563 patients [11.3%]; hazard ratio, 0.85; 95% confidence interval [CI], 0.79 to 0.92; P<0.001) and the key secondary end point (816 [5.9%] vs. 1013 [7.4%]; hazard ratio, 0.80; 95% CI, 0.73 to 0.88; P<0.001). The results were consistent across key subgroups, including the subgroup of patients in the lowest quartile for baseline LDL cholesterol levels (median, 74 mg per deciliter [1.9 mmol per liter]). There was no significant difference between the study groups with regard to adverse events (including new-onset diabetes and neurocognitive events), with the exception of injection-site reactions, which were more common with evolocumab (2.1% vs. 1.6%). Conclusions In our trial, inhibition of PCSK9 with evolocumab on a background of statin therapy lowered LDL cholesterol levels to a median of 30 mg per deciliter (0.78 mmol per liter) and reduced the risk of cardiovascular events. These findings show that patients with atherosclerotic cardiovascular disease benefit from lowering of LDL cholesterol levels below current targets. (Funded by Amgen; FOURIER ClinicalTrials.gov number, NCT01764633 .).

Concepts: Cholesterol, Myocardial infarction, Atherosclerosis, Cardiovascular disease, Low-density lipoprotein, Statin, Atheroma, Apolipoprotein B

339

Background Loss-of-function variants in the angiopoietin-like 3 gene (ANGPTL3) have been associated with decreased plasma levels of triglycerides, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol. It is not known whether such variants or therapeutic antagonism of ANGPTL3 are associated with a reduced risk of atherosclerotic cardiovascular disease. Methods We sequenced the exons of ANGPTL3 in 58,335 participants in the DiscovEHR human genetics study. We performed tests of association for loss-of-function variants in ANGPTL3 with lipid levels and with coronary artery disease in 13,102 case patients and 40,430 controls from the DiscovEHR study, with follow-up studies involving 23,317 case patients and 107,166 controls from four population studies. We also tested the effects of a human monoclonal antibody, evinacumab, against Angptl3 in dyslipidemic mice and against ANGPTL3 in healthy human volunteers with elevated levels of triglycerides or LDL cholesterol. Results In the DiscovEHR study, participants with heterozygous loss-of-function variants in ANGPTL3 had significantly lower serum levels of triglycerides, HDL cholesterol, and LDL cholesterol than participants without these variants. Loss-of-function variants were found in 0.33% of case patients with coronary artery disease and in 0.45% of controls (adjusted odds ratio, 0.59; 95% confidence interval, 0.41 to 0.85; P=0.004). These results were confirmed in the follow-up studies. In dyslipidemic mice, inhibition of Angptl3 with evinacumab resulted in a greater decrease in atherosclerotic lesion area and necrotic content than a control antibody. In humans, evinacumab caused a dose-dependent placebo-adjusted reduction in fasting triglyceride levels of up to 76% and LDL cholesterol levels of up to 23%. Conclusions Genetic and therapeutic antagonism of ANGPTL3 in humans and of Angptl3 in mice was associated with decreased levels of all three major lipid fractions and decreased odds of atherosclerotic cardiovascular disease. (Funded by Regeneron Pharmaceuticals and others; ClinicalTrials.gov number, NCT01749878 .).

Concepts: Cholesterol, Myocardial infarction, Atherosclerosis, Cardiovascular disease, Low-density lipoprotein, Atheroma, Niacin, High-density lipoprotein

319

Life skills play a key role in promoting educational and occupational success in early life, but their relevance at older ages is uncertain. Here we measured five life skills-conscientiousness, emotional stability, determination, control, and optimism-in 8,119 men and women aged 52 and older (mean 66.7 y). We show that the number of skills is associated with wealth, income, subjective wellbeing, less depression, low social isolation and loneliness, more close relationships, better self-rated health, fewer chronic diseases and impaired activities of daily living, faster walking speed, and favorable objective biomarkers (concentration of high-density lipoprotein cholesterol, vitamin D and C-reactive protein, and less central obesity). Life skills also predicted sustained psychological wellbeing, less loneliness, and a lower incidence of new chronic disease and physical impairment over a 4-y period. These analyses took account of age, sex, parental socioeconomic background, education, and cognitive function. No single life skill was responsible for the associations we observed, nor were they driven by factors such as socioeconomic status or health. Despite the vicissitudes of later life, life skills impact a range of outcomes, and the maintenance of these attributes may benefit the older population.

Concepts: Cholesterol, Psychology, Osteoporosis, Medicine, Nutrition, Asthma, Chronic, Cognition

280

Statins reduce LDL cholesterol and prevent vascular events, but their net effects in people at low risk of vascular events remain uncertain.

Concepts: Cholesterol, Myocardial infarction, Atherosclerosis, Low-density lipoprotein, Statin, Mevalonate pathway

224

Tendon pain occurs in individuals with extreme cholesterol levels (familial hypercholesterolaemia). It is unclear whether the association with tendon pain is strong with less extreme elevations of cholesterol.

Concepts: Cholesterol, Atherosclerosis, Lipid disorders, Hypercholesterolemia

213

The calcium channel of sperm (CatSper) is essential for sperm hyperactivated motility and fertility. The steroid hormone progesterone activates CatSper of human sperm via binding to the serine hydrolase ABHD2. However, steroid specificity of ABHD2 has not been evaluated. Here, we explored whether steroid hormones to which human spermatozoa are exposed in the male and female genital tract influence CatSper activation via modulation of ABHD2. The results show that testosterone, estrogen, and hydrocortisone did not alter basal CatSper currents, whereas the neurosteroid pregnenolone sulfate exerted similar effects as progesterone, likely binding to the same site. However, physiological concentrations of testosterone and hydrocortisone inhibited CatSper activation by progesterone. Additionally, testosterone antagonized the effect of pregnenolone sulfate. We have also explored whether steroid-like molecules, such as the plant triterpenoids pristimerin and lupeol, affect sperm fertility. Interestingly, both compounds competed with progesterone and pregnenolone sulfate and significantly reduced CatSper activation by either steroid. Furthermore, pristimerin and lupeol considerably diminished hyperactivation of capacitated spermatozoa. These results indicate that (i) pregnenolone sulfate together with progesterone are the main steroids that activate CatSper and (ii) pristimerin and lupeol can act as contraceptive compounds by averting sperm hyperactivation, thus preventing fertilization.

Concepts: Cholesterol, Sperm, Estrogen, Testosterone, Spermatozoon, Progesterone, Steroid, Pregnenolone

211

BACKGROUND: Intermittent fasting (IF; severe restriction 1 d/week) facilitates weight loss and improves coronary heart disease (CHD) risk indicators. The degree to which weight loss can be enhanced if IF is combined with calorie restriction (CR) and liquid meals, remains unknown. OBJECTIVE: This study examined the effects of IF plus CR (with or without a liquid diet) on body weight, body composition, and CHD risk. METHODS: Obese women (n = 54) were randomized to either the IFCR-liquid (IFCR-L) or IFCR-food based (IFCR-F) diet. The trial had two phases: 1) 2-week weight maintenance period, and 2) 8-week weight loss period. RESULTS: Body weight decreased more (P = 0.04) in the IFCR-L group (3.9 +/- 1.4 kg) versus the IFCR-F group (2.5 +/- 0.6 kg). Fat mass decreased similarly (P < 0.0001) in the IFCR-L and IFCR-F groups (2.8 +/- 1.2 kg and 1.9 +/- 0.7 kg, respectively). Visceral fat was reduced (P < 0.001) by IFCR-L (0.7 +/- 0.5 kg) and IFCR-F (0.3 +/- 0.5 kg) diets. Reductions in total and LDL cholesterol levels were greater (P = 0.04) in the IFCR-L (19 +/- 10%; 20 +/- 9%, respectively) versus the IFCR-F group (8 +/- 3%; 7 +/- 4%, respectively). LDL peak particle size increased (P < 0.01), while heart rate, glucose, insulin, and homocysteine decreased (P < 0.05), in the IFCR-L group only. CONCLUSION: These findings suggest that IF combined with CR and liquid meals is an effective strategy to help obese women lose weight and lower CHD risk.

Concepts: Cholesterol, Nutrition, Obesity, Mass, Adipose tissue, Weight loss, Dieting, Diets

195

Background: Postprandial hyperlipidemia is associated with impaired endothelial function. Peanut consumption favorably affects the lipid and lipoprotein profile; however, the effects on endothelial function remain unclear.Objective: The purpose of the study was to evaluate the effects of acute peanut consumption as part of a high-fat meal on postprandial endothelial function.Methods: We conducted a randomized, controlled, crossover postprandial study to evaluate the effect of acute peanut consumption on postprandial lipids and endothelial function as assessed by flow-mediated dilatation (FMD) of the brachial artery in 15 healthy overweight or obese men [mean age: 26.7 y; mean body mass index (in kg/m(2)): 31.4]. Participants consumed, in a randomized order, a peanut meal containing 3 ounces (85 g) ground peanuts (1198 kcal; 40.0% carbohydrate, 47.7% fat, 19.4% saturated fat, 13.2% protein) and a control meal matched for energy and macronutrient content. Meals were in the form of a shake, scheduled ≥1 wk apart. Lipids, lipoproteins, glucose, and insulin were measured at baseline (0 min) and at 30, 60, 120, and 240 min after shake consumption. FMD was measured at baseline and at 240 min.Results: Acute peanut consumption blunted the serum triglyceride (TG) response 120 and 240 min after consumption compared with the control meal (means ± SEMs-120 min: 188.9 ± 19.4 compared with 197.5 ± 20.7 mg/dL; 240 min: 189.9 ± 24.3 compared with 197.3 ± 18.4 mg/dL; P < 0.05 for both). Total, LDL, and HDL cholesterol and glucose and insulin responses were similar between the test meals. Compared with baseline, only the control meal significantly decreased FMD at 240 min (control: -1.2% ± 0.5%; P = 0.029; peanut: -0.6% ± 0.5%; P = 0.3). Participants with higher baseline total (>150 mg/dL) and LDL (>100 mg/dL)-cholesterol concentrations showed a significant decrease in FMD after the control meal (-1.8%, P = 0.017; -2.0%, P = 0.038), whereas the peanut meal maintained endothelial function in all participants irrespective of total- and LDL-cholesterol concentrations.Conclusion: The inclusion of 85 g peanuts (3 ounces) as part of a high-fat meal improved the postprandial TG response and preserved endothelial function in healthy overweight or obese men. This trial was registered at clinicaltrials.gov as NCT01405300.

Concepts: Cholesterol, Nutrition, Atherosclerosis, Insulin, Obesity, Fat, Lipoprotein, Lipid

189

Abstract Objective. This study aimed to investigate the association of lipoprotein and triglyceride levels with all-cause mortality in a population free from diabetes and cardiovascular disease (CVD) at baseline. The European Guidelines on cardiovascular disease prevention state that in general total cholesterol (TC) should be < 5 mmol/L (190 mg/dL) and low-density lipoprotein cholesterol (LDL-C) should be < 3 mmol/L (115 mg/dL). Design. A population-based register study in the period 1999-2007 including 118 160 subjects aged 50 + without statin use at baseline. All-cause mortality was related to lipoprotein and triglyceride levels and adjusted for statin use after inclusion. Results. All-cause mortality was lower in the groups with TC or LDL-C above the recommended levels. Compared with subjects with TC < 5 mmol/L, adjusted hazard ratios for the group aged 60-70 years ranged from 0.68 (95% confidence interval (CI) 0.61-0.77) for TC 5-5.99 mmol/L to 0.67 (95% CI 0.59-0.75) for TC 6-7.99 mmol/L and 1.02 (95% CI 0.68-1.53) for TC ≥ 8 mmol/L in males and from 0.57 (95% CI 0.48-0.67) to 0.59 (95% CI 0.50-0.68) and 1.02 (95% CI: 0.77-1.37) in females. For triglycerides, ratios compared with the group < 1 mmol/L in the females aged 60-70 years ranged from 1.04 (95% CI 0.88-1.23) to 1.35 (95% CI 1.10-1.66) and 1.25 (95% CI 1.05-1.48) for triglycerides 1-1.39 mmol/L, 1.4-1.69 mmol/L, and ≥ 1.7 mmol/L, respectively. Statin treatment after inclusion provided a survival benefit. Conclusion. These associations indicate that high lipoprotein levels do not seem to be definitely harmful in the general population. However, high triglyceride levels in females are associated with decreased survival.

Concepts: Cholesterol, Myocardial infarction, Atherosclerosis, Cardiovascular disease, Low-density lipoprotein, Statin, Atheroma, Triglyceride