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The unicellular green microalga

The selenium (Se) enrichment of yeasts and lactic acid bacteria (LAB) has recently emerged as a novel concept, the individual health effects of these beneficial microorganisms are combined by supplying the essential micronutrient Se in a more bioavailable and less toxic form. This study investigated the bioavailability of Se in the strains Enterococcus faecium CCDM 922A (EF) and Streptococcus thermophilus CCDM 144 (ST) and their respective Se-enriched forms, SeEF and SeST, in a CD (SD-Sprague Dawley) IGS rat model. Se-enriched LAB administration resulted in higher Se concentrations in the liver and kidneys of rats, where selenocystine was the prevalent Se species. The administration of both Se-enriched strains improved the antioxidant status of the animals. The effect of the diet was more pronounced in the heart tissue, where a lower glutathione reductase content was observed, irrespective of the Se fortification in LAB. Interestingly, rats fed diets with EF and SeEF had higher glutathione reductase activity. Reduced concentrations of serum malondialdehyde were noted following Se supplementation. Diets containing Se-enriched strains showed no macroscopic effects on the liver, kidneys, heart, and brain and had no apparent influence on the basic parameters of the lipid metabolism. Both the strains tested herein showed potential for further applications as promising sources of organically bound Se and Se nanoparticles.

Scope Infant formula (IF) uses besides vegetable fats also bovine milk fat, which differs in triacylglycerol (TAG) structure. Furthermore, it differs in fatty acid (FA) composition. Whether changing fat source in IF affects postprandial energy metabolism, lipemic response, and blood lipid profile is unknown. Methods and Results A proof‐of‐principle study, with a randomized controlled double‐blind cross‐over design, is conducted. Twenty healthy male adults consumed drinks with either 100% vegetable fat (VEG) or 67% bovine milk fat and 33% vegetable fat (BOV), on 2 separate days. For a detailed insight in the postprandial responses, indirect calorimetry is performed continuously, and venous blood samples are taken every 30 min, until 5 h postprandially. No differences in postprandial energy metabolism, serum lipids, lipoprotein, or chylomicron concentrations are observed between drinks. After consumption of VEG‐drink, C18:2n‐6 in serum increased. Observed differences in chylomicron FA profile reflect differences in initial FA profile of test drinks. Serum ketone bodies concentrations increase following consumption of BOV‐drink. Conclusions The use of bovine milk fat in IF does neither affect postprandial energy metabolism nor lipemic response in healthy adults, but alters postprandial FA profiles and ketone metabolism. Whether the exact same effects occur in infants requires experimental verification., To study the effects of different fat sources in infant formula on energy and lipid metabolism, a proof‐of‐principle study with young adults is conducted. Replacing 67% of vegetable fat in infant formula with bovine milk fat did not affect postprandial energy metabolism nor the lipemic response, the initial difference in fatty acid profile of the formulas is reflected in the chylomicrons, and serum ketone bodies increase with consumption of bovine milk fat. Whether the exact same effects occur in infants requires experimental verification.

Background: Patients with end-stage renal disease (ESRD) exhibit high morbidity as well as mortality for atherosclerotic cardiovascular diseases (CVD). Therefore, we investigated differences in individual lipoprotein classes and subclasses in ESRD patients under chronic high volume hemodiafiltration (HV-HDF) in comparison with a control group. We also assessed the prognosis of these patients and analyzed these parameters after 5 years follow-up. Methods: 57 patients and 50 controls were enrolled. We analysed high density (HDL) and low density (LDL) lipoprotein subfractions using the Quantimetrix Lipoprint(R) system. Subfractions were correlated with selected clinical-biochemical parameters including risk factors for atherosclerotic CVD at the beginning of and after 5 years follow-up. Results: Fourteen patients survived the 5-year follow-up. Follow-up results revealed a shift toward smaller HDL subfractions. In lipoproteins carrying apolipoprotein B, there was a shift of cholesterol from very low density (VLDL) to intermediate density (IDL) lipoproteins and LDLs. Hypolipidaemic therapy did not influence lipoprotein profiles in HV-HDF patients. Conclusions: 1. HV-HDF patients exhibit specific lipid profiles with elevated triacylglycerol, low HDL and LDL and higher content of cholesterol in remnant particles (VLDL and IDL) at the expense of large LDL. HDL subfractions were linked to the number of risk factors for CVD in the control group only. 2. Baseline lipoprotein profiles did not differ between survivors and non-survivors. Non-survivors had higher CRP and lower HDL-C. 3. During the 5 year follow-up period, cholesterol in HDL particles and lipoproteins carrying apolipoprotein B redistributed in survivors towards smaller particles, thus resembling the profile of control patients.

Summary Hydrogels based on copolymers of N-vinylpyrrolidone and ethylidene-bis-3-(N-vinyl-2-pyrrolidone) (EBVP) were prepared as polymer matrices for controlled release of high loads of hydrophilic compounds into the gastrointestinal tract. EBVP was synthesized and used as a crosslinking agent for the N-vinylpyrrolidone monomer. The polymerization mixtures, containing 65–80 wt.% of the model pharmacologically active compound, were polymerized to create cylindrical formulations. The release experiments were carried out under conditions corresponding to the digestive tract. Various compositions of hydrogel matrices were tested to reveal the influence of the active compound content and the crosslinking ratio on the release kinetics. Processes such as hydrogel swelling, dissolution and formulation disintegration were evaluated. The results obtained show that the system offers many possibilities to control the drug release to meet various medicinal requirements.

Mixed results have been obtained regarding the level of insulin resistance induced by high-fat diets rich in saturated fatty acids (SFA) when compared to those enriched by polyunsaturated fatty acids (PUFA), and how metabolic effects of marine PUFA of n-3 series, i.e. docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), depend on dietary lipid background. Here we compared two high-fat diets, in which the major lipid constituent was based either on SFA in the form of pork lard (LHF diet) or PUFA of n-6 series (Omega-6) as corn oil (cHF diet). Both cHF and LHF parental diets were also supplemented with EPA+DHA (∼30 g/kg diet) to produce cHF+F and LHF+F diet, respectively. Male C57BL/6N mice were fed the experimental diets for 8 weeks. Insulin sensitivity was assessed by hyperinsulinemic-euglycemic clamps in mice fed LHF and cHF diets, and then metabolic effects of cHF+F and LHF+F diets were assessed focusing on the liver and epididymal white adipose tissue (eWAT). Both LHF and cHF induced comparable weight gain and the level of insulin resistance, however LHF-fed mice showed increased hepatic steatosis associated with elevated activity of stearoyl-CoA desaturase-1 (SCD1), and lower plasma triacylglycerol levels when compared to cHF. Despite lowering hepatic SCD1 activity, which was concomitant with reduced hepatic steatosis reaching the level observed in cHF+F mice, LHF+F did not decrease adiposity and the weight of eWAT, and rather further impaired insulin sensitivity relative to cHF+F, that tended to improve it. In conclusion, high-fat diets containing as much as ∼35 weight% as lipids induce similar weight gain and impairment of insulin sensitivity irrespective whether they are based on SFA or Omega-6. Although the SFA-rich diet containing EPA+DHA efficiently reduced hepatic steatosis, it did so without a corresponding improvement in insulin sensitivity and in the absence of effect on adiposity.

Omega-3 polyunsatuarted fatty acids (PUFA) are associated with hypolipidemic and anti-inflammatory effects. However, omega-3 PUFA, usually administered as triacylglycerols or ethyl esters, could also compromise glucose metabolism, especially in obese type 2 diabetics. Phospholipids represent an alternative source of omega-3 PUFA, but their impact on glucose homeostasis is poorly explored. Male C57BL/6N mice were fed for 8 weeks a corn oil-based high-fat diet (cHF) alone or cHF-based diets containing eicosapentaenoic acid and docosahexaenoic acid (~3%; wt/wt), admixed either as a concentrate of re-esterified triacylglycerols (ω3TG) or Krill oil containing mainly phospholipids (ω3PL). Lean controls were fed a low-fat diet. Insulin sensitivity (hyperinsulinemic-euglycemic clamps), parameters of glucose homeostasis, adipose tissue function, and plasma levels of N-acylethanolamines, monoacylglycerols and fatty acids were determined. Feeding cHF induced obesity and worsened (~4.3-fold) insulin sensitivity as determined by clamp. Insulin sensitivity was almost preserved in ω3PL but not ω3TG mice. Compared with cHF mice, endogenous glucose production was reduced to 47%, whereas whole-body and muscle glycogen synthesis increased ~3-fold in ω3PL mice that showed improved adipose tissue function and elevated plasma adiponectin levels. Besides eicosapentaenoic and docosapentaenoic acids, principal component analysis of plasma fatty acids identified palmitoleic acid (C16:1n-7) as the most discriminating analyte whose levels were increased in ω3PL mice and correlated negatively with the degree of cHF-induced glucose intolerance. While palmitoleic acid from Krill oil may help improve glucose homeostasis, our findings provide a general rationale for using omega-3 PUFA-containing phospholipids as nutritional supplements with potent insulin-sensitizing effects.

Obesity in childhood increases the risk of obesity in adulthood and is predictive for the development of metabolic disorders. The fatty acid composition is associated with obesity and obesity-associated disorders. We investigated the relationship between serum fatty acids composition, adiposity, lipids profile, parameters of glucose metabolism and leptin. The study subjects were 380 adolescents aged 15.0-17.9 years. The study's variables included anthropometric measurements, levels of serum lipids and hormonal parameters. Individual fatty acids were determined in plasma by gas-liquid chromatography. Palmitoleic acid (16:1n-7, PA) significantly positively correlated with percentage of body fat. Saturated fatty acids in phospholipids (PL) positively correlated with BMI and percentage of body fat. PA content in all lipids classes positively correlated with total cholesterol (TC), HDL cholesterol, triglycerides (TG) levels. Stearoyl-CoA desaturase (SCD) activity positively correlated with percentage of body fat and positive correlations of SCD and PA level with leptin were found. Plasma PA content and SCD are associated with adiposity and leptin in obese adolescents. No significant correlation between PA level and insulin resistance was found. Palmitoleate positively correlated with TC, HDL cholesterol, TG and LDL cholesterol levels.

Introduction: The prevalence of cardiovascular diseases is relatively high in Central European countries, which may be caused by unhealthy dietary habits and cigarette smoking. The traditional Czech diet is low in seafood – a food reported to offer some reduction of risk for myocardial infarct and stroke. The European Health Authority recommends regular intake of fish or food supplements providing at least 250 mg of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) daily. Material and methods: The present study included 100 subjects from Prague not eating fish. They were given herring fish oil capsules providing aproximately the recommended dose of EPA + DHA for 6 months. Omega-3 and other fatty acids were analysed from red blood cells (RBC) before and after study completion. Study parameters were omega-3 index, EPA + DHA, and the atherogenic index comprising saturated fatty acids divided by unsaturated fatty acids. Results: Mean omega-3 index at study entry was 5.1% (p < 0.01) increasing to 10.7%, while mean EPA + DHA increased by 112% (p < 0.01). Conclusions: Capsules of herring oil containing 250 mg EPA + DHA daily increased RBC content of omega-3 fatty acids, increasing the omega-3 index to low or intermediate risk values in 83% of the subjects studied. In populations with low access to or no tradition of eating fish, herring oil capsules providing the EU recommended dose of omega-3 fatty acids might reduce cardiovascular risk as indicated by the surrogate parameter omega-3 index.

Hyperlipidemia treatment based on niacin requires gastrointestinal administration of relatively high doses. The recommended dietary allowance of niacin as vitamin B3 is 14 to 16 mg daily in adults, while the doses of niacin used in the treatment of hyperlipidemia are generally in the range of 1 to 3 g. Administration of such large doses requires a high concentration of the active compound in the tablet and proper control of the drug release. In this study, a hydrogel matrix based on poly(2-hydroxyethyl methacrylate) and polyvinylpyrrolidone was investigated as delivery vehicle for controlled NA release into the gastrointestinal environment. The prepared hydrogel matrices varied in used monomer and crosslinker types and concentrations. The content of NA in tablets was between 65-80 %. The release profiles of NA from tablets were examined under three different pH values (1, 4.5 and 6.8) over the time period of 30 h. The effects of the monomer ratio, the crosslinking of the polymer network, and the solubility of niacin during drug release under various pH are discussed. The results showed that the release time period can be achieved in a relatively wide range of time and can be adjusted according to the medical requirements.