Mineralization of vegetable oils used for thermal weed control in arable soils

Hot vegetable oil can be used for weed control as an alternative to the use of herbicides. We analysed the temporal development of vegetable oil mineralization in soil and tested the role of nutrient supply on oil mineralization. Further, we investigated the effect of oil application on mineralization of native soil organic carbon (SOC), i.e. the priming effect. In a laboratory experiment, three oil dosages (0.1, 1.0 and 3.0ml per 35g soil) were applied to three arable soils and soil respiration was measured hourly. Both a C3-sunflower oil and a C4-corn oil were used in order to differentiate oil-derived CO2 from SOC-derived CO2. The results revealed that after 42days of incubation, 9.6 to 39.7% of the applied oil was mineralized which, however, also primed the mineralization of SOC by a factor of 2.2 to 4.2. The higher the applied oil amount, the lower was the percentage of oil-C mineralization, but the higher was the priming effect. The addition of fertilizer (0.29mgNg(-1) soil and 0.048mgPg(-1) soil) increased oil-C mineralization to 39.9 to 50.9%. We conclude that oil can temporarily accumulate in soil, especially in case of low nutrient supply. As the addition of oil stimulates SOC mineralization, a decrease of native SOC stocks may occur, which needs further quantification in long-term field experiments.Peer reviewe

Top-Down Lipidomics Reveals Ether Lipid Deficiency in Blood Plasma of Hypertensive Patients

BACKGROUND: Dyslipoproteinemia, obesity and insulin resistance are integrative constituents of the metabolic syndrome and are major risk factors for hypertension. The objective of this study was to determine whether hypertension specifically affects the plasma lipidome independently and differently from the effects induced by obesity and insulin resistance. METHODOLOGY/PRINCIPAL FINDINGS: We screened the plasma lipidome of 19 men with hypertension and 51 normotensive male controls by top-down shotgun profiling on a LTQ Orbitrap hybrid mass spectrometer. The analysis encompassed 95 lipid species of 10 major lipid classes. Obesity resulted in generally higher lipid load in blood plasma, while the content of tri- and diacylglycerols increased dramatically. Insulin resistance, defined by HOMA-IR >3.5 and controlled for BMI, had little effect on the plasma lipidome. Importantly, we observed that in blood plasma of hypertensive individuals the overall content of ether lipids decreased. Ether phosphatidylcholines and ether phosphatidylethanolamines, that comprise arachidonic (20:4) and docosapentaenoic (22:5) fatty acid moieties, were specifically diminished. The content of free cholesterol also decreased, although conventional clinical lipid homeostasis indices remained unaffected. CONCLUSIONS/SIGNIFICANCE: Top-down shotgun lipidomics demonstrated that hypertension is accompanied by specific reduction of the content of ether lipids and free cholesterol that occurred independently of lipidomic alterations induced by obesity and insulin resistance. These results may form the basis for novel preventive and dietary strategies alleviating the severity of hypertension

Repeated lipoprotein apheresis and immune response: Effects on different immune cell populations

BACKGROUND Atherosclerosis is considered a chronic inflammation of arterial vessels with the involvement of several immune cells causing severe cardiovascular diseases. Lipoprotein apheresis (LA) improves cardiovascular conditions of patients with severely disturbed lipid metabolism. In this context, little is known about the impact of LA on various immune cell populations, especially over time. METHODS Immune cells of 18 LA-naïve patients starting weekly LA treatment were analyzed before and after four apheresis cycles over the course of 24 weeks by flow cytometry. RESULTS AND CONCLUSIONS An acute lowering effect of LA on T cell and natural killer (NK) cell subpopulations expressing CD69 was observed. The non-classical and intermediate monocyte subsets as well as HLA-DR$^{+}$ 6-sulfo LacNAc$^{+}$ monocytes were significantly reduced during the apheresis procedure. We conclude that LA has the capacity to alter various immune cell subsets. However, LA has mainly short-term effects than long-term consequences on proportions of immune cells

Gender, Contraceptives and Individual Metabolic Predisposition Shape a Healthy Plasma Lipidome

Lipidomics of human blood plasma is an emerging biomarker discovery approach that compares lipid profiles under pathological and physiologically normal conditions, but how a healthy lipidome varies within the population is poorly understood. By quantifying 281 molecular species from 27 major lipid classes in the plasma of 71 healthy young Caucasians whose 35 clinical blood test and anthropometric indices matched the medical norm, we provided a comprehensive, expandable and clinically relevant resource of reference molar concentrations of individual lipids. We established that gender is a major lipidomic factor, whose impact is strongly enhanced by hormonal contraceptives and mediated by sex hormone-binding globulin. In lipidomics epidemiological studies should avoid mixed-gender cohorts and females taking hormonal contraceptives should be considered as a separate sub-cohort. Within a gender-restricted cohort lipidomics revealed a compositional signature that indicates the predisposition towards an early development of metabolic syndrome in ca. 25% of healthy male individuals suggesting a healthy plasma lipidome as resource for early biomarker discovery

A principal component meta-analysis on multiple anthropometric traits identifies novel loci for body shape

Large consortia have revealed hundreds of genetic loci associated with anthropometric traits, one trait at a time. We examined whether genetic variants affect body shape as a composite phenotype that is represented by a combination of anthropometric traits. We developed an approach that calculates averaged PCs (AvPCs) representing body shape derived from six anthropometric traits (body mass index, height, weight, waist and hip circumference, waist-to-hip ratio). The first four AvPCs explain >99% of the variability, are heritable, and associate with cardiometabolic outcomes. We performed genome-wide association analyses for each body shape composite phenotype across 65 studies and meta-analysed summary statistics. We identify six novel loci: LEMD2 and CD47 for AvPC1, RPS6KA5/C14orf159 and GANAB for AvPC3, and ARL15 and ANP32 for AvPC4. Our findings highlight the value of using multiple traits to define complex phenotypes for discovery, which are not captured by single-trait analyses, and may shed light onto new pathways.Peer reviewe

Associations of plasma lipidomic profile with insulin sensitivity indices-data used for figures 1-3

Supplemental material to article “Detection of Independent Associations of Plasma Lipidomic Parameters with Insulin Sensitivity Indices Using Data Mining Methodology” by Kopprasch et al., which includes data used for figures 1-3

Aldosterone Hypothesis for Cognitive Impairment in Diabetes Mellitus

Increased plasma aldosterone concentration is significantly associated with dementia, which is accentuated by diabetes mellitus (DM). Angiotensin II (AngII) deteriorates cognitive function through neuronal degradation. Lipoproteins, a major source of cholesterol for aldosterone biosynthesis, undergo glycoxidative modifications in the presence of hyperglycemia. We hypothesize that there would be a pathophysiological link between diabetically-modified lipoproteins, angiotensin II, and increased plasma aldosterone concentration for induction of cognitive impairment. Glycoxidized lipoproteins produce significantly more aldosterone from AngII-sensitized adrenocortical cells compared to their native counterparts. The elucidation of signaling mechanisms revealed that modified lipoproteins follow the similar signaling mechanism like AngII for adrenocortical aldosterone release via ERK1/2 and Janus kinase-2 (Jak-2)-mediated pathways. The enhanced aldosterone release from AngII-sensitized adrenocortical cells induced by glycoxidatively modified lipoproteins may play a crucial role in cognitive dysfunction in diabetic individuals along with AngII via a prevailing mode of signaling cascade involving ERK1/2- and Jak-2-dependent pathways

Short- and long-term effects of lipoprotein apheresis on plasma hormones in patients with therapy-resistant dyslipidemia

BACKGROUND AND AIMS Lipoprotein apheresis (LA) is a highly effective method to improve the clinical and metabolic situation in patients with therapy-resistant disorders of lipid metabolism. Cholesterol is the substrate for the synthesis of all steroid hormones. If repeated massive reduction of LDL-cholesterol may interfere with human adrenal steroidogenesis, and could become clinically relevant is unknown, so far. Thus, the aim of this study was to determine possible short- and long-term effects of LA on blood plasma levels of ACTH, cortisol, aldosterone, DHEAS, renin and testosterone. METHODS In total, 39 patients, treated with one of four LA techniques were studied: 1. Lipid Filtration (LF; n = 7), 2. Dextran Sulfate Adsorption (DSA; n = 7), 3. Membrane Filtration Optimised Novel Extracorporeal Treatment (MONET; n = 8), and 4. Direct Absorption of Lipoproteins (DALI; n = 15). Hormone levels were analyzed before and after five LA sessions with an interval of 20 weeks covering a total observation time of two years. In addition patients were comprehensively characterized by clinical and laboratory data. RESULTS Patients treated with LA revealed an acute reduction of steroid hormones and ACTH, independent of apheresis technology but no long-term insufficiency in steroidogenesis was observed. Plasma renin levels were stable in LF patients and were highly elevated in patients under DSA, MONET and DALI apheresis throughout the observation period. CONCLUSIONS In summary, these data suggest that although different LA techniques considerably differ in their acute effects on hormone levels during LA, they did not alter long-term hormone levels sustainably

Long-term follow-up of circulating oxidative stress markers in patients undergoing lipoprotein apheresis by Direct Adsorption of Lipids (DALI)

OBJECTIVE: Beyond its well-established efficacy in lowering atherogenic lipids and lipoproteins, DALI (Direct Adsorption of Lipids) apheresis has been shown to have acute anti-inflammatory and endothelium-protective effects. In the present study, we investigated long-term effects of DALI procedures on circulating oxidative stress markers. METHODS: Thirteen patients involved in the study underwent regular DALI apheresis for nearly two years. At sessions 1, 40 and 80 conventional lipid status and changes of systemic oxidative stress markers (oxidized LDL, anti-oxidized LDL antibodies, advanced oxidation protein products (AOPP), and myeloperoxidase (MPO)) were examined. RESULTS: DALI procedure efficiently reduced atherogenic lipids/lipoproteins. On day three after apheresis lipid parameters returned to pre-apheresis values. They showed no tendency to increase or to decrease over time. No significant differences were found between 1st, 40th and 80th sessions. In a similar way, levels of oxidative stress biomarkers acutely decreased after apheresis sessions and rebounded on day three after apheresis. No significant differences were observed between sessions 1, 40, and 80. CONCLUSION: DALI apheresis repeatedly decreases atherogenic lipid/lipoprotein profile and oxidative stress biomarker levels during each session. Among all investigated parameters no longitudinal effects over two years could be observed

Association between systemic oxidative stress and insulin resistance/sensitivity indices - the PREDIAS study

OBJECTIVE Systemic oxidative stress has been causally related to insulin resistance and the subsequent development of type 2 diabetes mellitus (T2D). We investigated associations between circulating oxidative stress markers and different surrogate indexes of insulin sensitivity/resistance. PATIENTS Cross-sectional data were obtained from 1183 subjects with normal glucose tolerance (NGT), 280 subjects with impaired glucose tolerance (IGT) and 69 newly detected T2D individuals entering the PREDIAS (prevention of diabetes) study. MEASUREMENTS Following oral glucose tolerance test, five different insulin sensitivity/resistance indices were estimated: homoeostasis model of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), early phase insulin release (EPIR), insulin sensitivity index (ISI) and disposition index (DI). Additionally, circulating phagocyte generation of reactive oxygen species (ROS) and plasma total antioxidant capacity (TAC) was measured. RESULTS After adjustment for five covariates, HOMA-IR was significantly increased in IGT and T2D subjects when compared to NGT subjects (P = 0·000). QUICKI (P = 0·000), ISI (P = 0·000), EPIR (0·005/0·012) and DI (P = 0·000) were significantly attenuated in IGT and T2D. The prevalence of IGT and T2D individuals increased with increasing ROS generation and TAC tertiles. Increased systemic ROS generation was paralleled by increased HOMA-IR (P < 0·001, tertile 1/T1/vs tertile 3/T3/), decreased QUICKI (P < 0·001, T1 vs T3) and decreased ISI (P < 0·05, T1 vs T3). A similar tendency for indices was observed when comparing TAC tertiles: increase in HOMA-IR, decrease in QUICKI and ISI (P < 0·001, T1 vs T3 each). EPIR and DI did not differ significantly across ROS generation and TAC tertiles. CONCLUSIONS Systemic oxidative stress is associated with elevated insulin resistance index HOMA-IR, and decreased insulin sensitivity surrogates QUICKI and ISI