Methylophiopogonanone A, an Ophiopogon homoisoflavonoid, alleviates high-fat diet-induced hyperlipidemia: assessment of its potential mechanism.

Methylophiopogonanone A (MO-A), a homoisoflavonoid extracted from Ophiopogon japonicus, has been shown to attenuate myocardial apoptosis and improve cerebral ischemia/reperfusion injury. However, the hypolipidemic effects remain unknown. This study was performed to investigate a potential hypolipidemic effect of MO-A in hyperlipidemia rats, as well as its underlying mechanism of action. A rat model of hyperlipidemia was induced by a high-fat diet (HFD). Animals were randomly divided into three groups (n=8/group): normal control group (NC), HFD group, and HFD+MO-A (10 mg·kg-1·d-1) treatment group. The effects of MO-A on serum lipids, body weight, activity of lipoprotein metabolism enzyme, and gene expression of lipid metabolism were evaluated in HFD-induced rats. In HFD-induced rats, pretreatment with MO-A decreased the body weight gain and reduced serum and hepatic lipid levels. In addition, pretreatment with MO-A improved the activities of lipoprotein lipase and hepatic lipase in serum and liver, down-regulated mRNA expression of acetyl CoA carboxylase and sterol regulatory element-binding protein 1c, and up-regulated mRNA expression of low-density lipoprotein receptor and peroxisome proliferator-activated receptor α in the liver. Our results indicated that MO-A showed strong ability to ameliorate the hyperlipidemia in HFD-induced rats. MO-A might be a potential candidate for prevention of overweight and dyslipidemia induced by HFD.

Starch sources influence lipidaemia of diabetic dogs.

BACKGROUND: Hyperlipidaemia is considered a cause of other diseases that are clinically important and potentially life threatening. Combination of pea and barley as exclusive starch sources is known to interfere with glycemic control in diabetic dogs, but their effect on lipid profile of hiperlipidaemic dogs is yet to be evaluated. Twelve adult diabetic dogs were fed three dry extruded diets with different starch sources and different fat levels: peas and barley (PB), maize (Mi), and peas, barley and rice (Ba) with 15.7, 15.6 and 9.0% of their dry matter as fat, respectively. Plasmatic cholesterol and triglycerides concentration curves over 10 h were obtained after 60 days on each diet and with the same NPH insulin dose. ANOVA test or Friedman test were used to compare the dietary effects on triglycerides and cholesterol variables among the diets. RESULTS: Dogs presented lower mean (p = 0.05), fasting (p = 0.03), and time 8-h postprandial (p = 0.05) triglyceridemia after PB diet period than Ba diet period and time 4-h postprandial (p = 0.02) lower after PB than Mi diet. Cholesterolemia mean, minimum, maximum, area under the cholesterol curve and times points: 2, 4, 6, 8 and 10-h postprandial, had lower values after PB ingestion in comparison to Mi, without difference to Ba diet. CONCLUSION: Inclusion of pea and barley, as exclusive starch sources, in therapeutic diets for diabetic dogs can minimize plasmatic triglycerides and cholesterol concentration at fasting and at different postprandial time, compared to the maize diet or diet with lesser fat content.

Methylophiopogonanone A, an Ophiopogon homoisoflavonoid, alleviates high-fat diet-induced hyperlipidemia: assessment of its potential mechanism

Methylophiopogonanone A (MO-A), a homoisoflavonoid extracted from Ophiopogon japonicus, has been shown to attenuate myocardial apoptosis and improve cerebral ischemia/reperfusion injury. However, the hypolipidemic effects remain unknown. This study was performed to investigate a potential hypolipidemic effect of MO-A in hyperlipidemia rats, as well as its underlying mechanism of action. A rat model of hyperlipidemia was induced by a high-fat diet (HFD). Animals were randomly divided into three groups (n=8/group): normal control group (NC), HFD group, and HFD+MO-A (10 mg·kg-1·d-1) treatment group. The effects of MO-A on serum lipids, body weight, activity of lipoprotein metabolism enzyme, and gene expression of lipid metabolism were evaluated in HFD-induced rats. In HFD-induced rats, pretreatment with MO-A decreased the body weight gain and reduced serum and hepatic lipid levels. In addition, pretreatment with MO-A improved the activities of lipoprotein lipase and hepatic lipase in serum and liver, down-regulated mRNA expression of acetyl CoA carboxylase and sterol regulatory element-binding protein 1c, and up-regulated mRNA expression of low-density lipoprotein receptor and peroxisome proliferator-activated receptor α in the liver. Our results indicated that MO-A showed strong ability to ameliorate the hyperlipidemia in HFD-induced rats. MO-A might be a potential candidate for prevention of overweight and dyslipidemia induced by HFD.

Short-Term Betanin Intake Reduces Oxidative Stress in Wistar Rats.

Oxidative stress is a common condition described in risk factors for cardiovascular disease. Betanin, a bioactive pigment from red beetroot demonstrates anti-inflammatory and antioxidant properties. The main aim of this study was to evaluate the short-term intake of betanin against oxidative stress in a rodent model, a common condition described in several risk factors for cardiovascular disease. Oxidative stress was induced in Wistar rats by a hyperlipidemic diet for 60 days, followed by betanin administration (20 mg·kg-1) through oral gavage for 20 days. Plasma biochemical parameters and antioxidant enzyme activities were evaluated. Lipid peroxidation and histopathological changes were determined in the liver. The hyperlipidemic diet caused hyperglycemia, hyperinsulinemia, insulin resistance, and increases in alanine transaminase and aspartate transaminase levels. Oxidative stress status was confirmed by reduction of antioxidant enzyme activities, increased lipid peroxidation, and liver damage. Purified betanin regulated glucose levels, insulin, and insulin resistance. Hepatic damage was reversed as evidenced by the reduction in alanine transaminase and aspartate transaminase levels and confirmed by histological analyses. Betanin reduced hepatic malondialdehyde and increased superoxide dismutase, catalase, and glutathione peroxidase activities. Short-term betanin intake modulated biochemical parameters, reversed hepatic tissue damage, and attenuated oxidative stress in Wistar rats.

Attenuation of atherogenic apo B-48-dependent hyperlipidemia and high density lipoprotein remodeling induced by vitamin C and E combination and their beneficial effect on lethal ischemic heart disease in mice.

BACKGROUND AND AIMS: Atherosclerotic cardiovascular disease is highly prevalent and its underlying pathogenesis involves dyslipidemia including pro-atherogenic high density lipoprotein (HDL) remodeling. Vitamins C and E have been proposed as atheroprotective agents for cardiovascular disease management. However, their effects and benefits on high density lipoprotein function and remodeling are unknown. In this study, we evaluated the role of vitamin C and E on non HDL lipoproteins as well as HDL function and remodeling, along with their effects on inflammation/oxidation biomarkers and atherosclerosis in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. METHODS AND RESULTS: Mice were pre-treated for 5 weeks before and during atherogenic diet feeding with vitamin C and E added to water and diet, respectively. Compared to a control group, combined vitamin C and E administration reduced serum total cholesterol and triglyceride levels by decreasing apo B-48-containing lipoproteins, remodeled HDL particles by reducing phospholipid as well as increasing PON1 and apo D content, and diminished PLTP activity and levels. Vitamin supplementation improved HDL antioxidant function and lowered serum TNF-α levels. Vitamin C and E combination attenuated atherogenesis and increased lifespan in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. CONCLUSIONS: Vitamin C and E administration showed significant lipid metabolism regulating effects, including HDL remodeling and decreased levels of apoB-containing lipoproteins, in mice. In addition, this vitamin supplementation generated a cardioprotective effect in a murine model of severe and lethal atherosclerotic ischemic heart disease.

Attenuation of atherogenic apo B-48-dependent hyperlipidemia and high density lipoprotein remodeling induced by vitamin C and E combination and their beneficial effect on lethal ischemic heart disease in mice

BACKGROUND AND AIMS: Atherosclerotic cardiovascular disease is highly prevalent and its underlying pathogenesis involves dyslipidemia including pro-atherogenic high density lipoprotein (HDL) remodeling. Vitamins C and E have been proposed as atheroprotective agents for cardiovascular disease management. However, their effects and benefits on high density lipoprotein function and remodeling are unknown. In this study, we evaluated the role of vitamin C and E on non HDL lipoproteins as well as HDL function and remodeling, along with their effects on inflammation/ oxidation biomarkers and atherosclerosis in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. METHODS AND RESULTS: Mice were pre-treated for 5 weeks before and during atherogenic diet feeding with vitamin C and E added to water and diet, respectively. Compared to a control group, combined vitamin C and E administration reduced serum total cholesterol and triglyceride levels by decreasing apo B-48-containing lipoproteins, remodeled HDL particles by reducing phospholipid as well as increasing PON1 and apo D content, and diminished PLTP activity and levels. Vitamin supplementation improved HDL antioxidant function and lowered serum TNF-α levels. Vitamin C and E combination attenuated atherogenesis and increased lifespan in atherogenic diet-fed SR-B1 KO/ApoER61h/h mice. CONCLUSIONS: Vitamin C and E administration showed significant lipid metabolism regulating effects, including HDL remodeling and decreased levels of apoB-containing lipoproteins, in mice. In addition, this vitamin supplementation generated a cardioprotective effect in a murine model of severe and lethal atherosclerotic ischemic heart disease.

Daytime increase in caloric intake without change in total 24-h caloric intake can increase adiposity but not total bodyweight in rats with inverted feeding pattern.

The goal of this study was to evaluate the effect of the food availability period on body weight, self-selection of macronutrients, adiposity, lipoprotein, and serum glucose profiles without changing energy intake. Young male rats were divided into 2 groups according to the availability of food during the light and dark phases of the cycle, forming 2 groups: control group (CG) and group with inverted feeding pattern (IFPG). Before inversion of food availability on the 80th day, circadian food intake was measured every 4 h over 24 h during 3 days. The glycemic curve, an oral test for glucose tolerance, and self-selection of macronutrients were evaluated. Blood samples were collected for analysis of fasting glucose, triglycerides, and total cholesterol fractions. The IFPG showed an increase in fasting glucose in the dark phase of the cycle, changes in the glycemic curve, and oral glucose tolerance test. It also showed increased abdominal and liver fat and distinct choice of macronutrients compared with the CG. A change in the availability of food according to the phase of the circadian cycle produces changes in glucose and feeding circadian rhythm culminating in increased abdominal and hepatic fat. These effects can increase the risk of metabolic disorders and installation of chronic diseases.

Lipidomic and Antioxidant Response to Grape Seed, Corn and Coconut Oils in Healthy Wistar Rats.

Specialty oils differ in fatty acid, phytosterol and antioxidant content, impacting their benefits for cardiovascular health. The lipid (fatty acid, phytosterol) and antioxidant (total phenolics, radical scavenging capacity) profiles of grapeseed (GSO), corn (CO) and coconut (CNO) oils and their physiological (triacylglycerides, total and HDL-cholesterol and antioxidant capacity (FRAP) in serum and fatty acid and phytosterol hepatic deposition) and genomic (HL, LCAT, ApoA-1 and SR-BP1 mRNA hepatic levels) responses after their sub-chronic intake (10% diet for 28 days) was examined in healthy albino rats. Fatty acid, phytosterol and antioxidant profiles differed between oils (p ≤ 0.01). Serum and hepatic triacylglycerides and total cholesterol increased (p ≤ 0.01); serum HDL-Cholesterol decreased (p < 0.05); but serum FRAP did not differ (p > 0.05) in CNO-fed rats as compared to CO or GSO groups. Hepatic phytosterol deposition was higher (+2.2 mg/g; p ≤ 0.001) in CO- than GSO-fed rats, but their fatty acid deposition was similar. All but ApoA-1 mRNA level increased in GSO-fed rats as compared to other groups (p ≤ 0.01). Hepatic fatty acid handling, but not antioxidant response, nor hepatic phytosterol deposition, could be related to a more efficient reverse-cholesterol transport in GSO-fed rats as compared to CO or CNO.

Effect of prebiotics of Agave salmiana fed to healthy Wistar rats.

BACKGROUND: Inulin and other fructans are synthesized and stored in mezcal agave (Agave salmiana). Fructans provide several health benefits and have excellent technological properties, but only few data report their physiological effect when added in the diet. RESULTS: Here, we studied the physiological effects of fructans obtained from A. salmiana when added in the diet of Wistar rats. Results showed favorable changes on Wistar rats when the fructans was added to their diet, including the decrease of the pH in the feces and the increase of the number of lactic acid bacteria (CFU g-1 ) (Lactobacillus spp. and Bifidobacterium spp.), even these changes were enhanced with the synbiotic diet (fructans plus B. animalis subsp. lactis). Synbiotic diet, developed changes in the reduction of cholesterol and triglycerides concentrations in serum, with statistical differences (P < 0.05). Histological analysis of colon sections showed that synbiotic diet promoted colon cells growth suggesting that fructans from A. salmiana confer beneficial health effects through gut microbiota modulation. CONCLUSION: Our data underline the advantage of targeting the gut microbiota by colonic nutrients like specific structure of fructans from A. salmiana, with their beneficial effects. More studies are necessary to define the role of fructans to develop more solid therapeutic solutions in humans. © 2016 Society of Chemical Industry.

Effect of exercise intensity on postprandial lipemia, markers of oxidative stress, and endothelial function after a high-fat meal.

The aim of this study was to compare the effects of 2 different exercise intensities on postprandial lipemia, oxidative stress markers, and endothelial function after a high-fat meal (HFM). Eleven young men completed 2-day trials in 3 conditions: rest, moderate-intensity exercise (MI-Exercise) and heavy-intensity exercise (HI-Exercise). Subjects performed an exercise bout or no exercise (Rest) on the evening of day 1. On the morning of day 2, an HFM was provided. Blood was sampled at fasting (0 h) and every hour from 1 to 5 h during the postprandial period for triacylglycerol (TAG), thiobarbituric acid reactive substance (TBARS), and nitrite/nitrate (NOx) concentrations. Flow-mediated dilatation (FMD) was also analyzed. TAG concentrations were reduced in exercise conditions compared with Rest during the postprandial period (P < 0.004). TAG incremental area under the curve (iAUC) was smaller after HI-Exercise compared with Rest (P = 0.012). TBARS concentrations were reduced in MI-Exercise compared with Rest (P < 0.041). FMD was higher in exercise conditions than Rest at 0 h (P < 0.02) and NOx concentrations were enhanced in MI-Exercise compared with Rest at 0 h (P < 0.01). These results suggest that acute exercise can reduce lipemia after an HFM. However, HI-Exercise showed to be more effective in reducing iAUC TAG, which might suggest higher protection against postprandial TAG enhancement. Conversely, MI-Exercise can be beneficial to attenuate the susceptibility of oxidative damage induced by an HFM and to increase endothelial function in the fasted state compared with Rest.

Diet-Induced Weight Loss Reduces DNA Damage and Cardiometabolic Risk Factors in Overweight/Obese Women with Polycystic Ovary Syndrome.

AIMS: We aimed to investigate the impact of following a diet to induce weight loss (500 kcal deficit per day) over DNA damage and cardiometabolic risk factors in women with overweight/obesity diagnosed with polycystic ovary syndrome (PCOS). METHODS: A study was conducted in Natal, RN, Brazil selecting overweight/obese (body mass index ≥25 and <39 kg/m2) women (18-35 years). The levels of DNA damage were assessed by a single cell gel electrophoresis. Repeated 24 h dietary recall questionnaires, anthropometry, biochemical profile and sex hormones were collected at baseline and after 12 weeks of intervention. RESULTS: Women exhibiting a decrease in the markers of DNA damage: tail intensity (24.35 ± 5.86 - pre diet vs. 17.15 ± 5.04 - post-diet; p < 0.001) and tail moment (20.47 ± 7.85 - pre diet vs. 14.13 ± 6.29 - post-diet; p < 0.002). Reduction of calorie intake, weight loss, decreased sexual hormone and cardiometabolic markers such as insulin, homeostasis model assessment of insulin resistance and low-density lipoprotein cholesterol were verified In the multivariate regression analysis, quantitative insulin sensitivity check index and progesterone were responsible for the variation markers in DNA damage before the diet, losing its influence upon diet. CONCLUSION: DNA damage and the impact of cardiometabolic risk factors decreased after the intervention in women with PCOS, indicating the relevance of a nutritional approach in this group of patients.

Perfil lipídico en embarazadas durante el tercer trimestre según índice de masa corporal y consumo de grasas / Lipid profile in pregnant women during the third quarter according to body mass index and fat intake

Introducción: el embarazo es una condición que implica una adaptación metabólica para suplir los requerimientos del feto en desarrollo. Durante la gestación ocurre un aumento de los lípidos circulantes, lo que conlleva a un incremento en la peroxidación lipídica. En condiciones normales, este fenómeno se ve compensado por una elevación en los sistemas antioxidantes. Objetivo: comparar el perfil lipídico en mujeres embarazadas según el índice de masa corporal y la frecuencia de consumo de grasa. Métodos: se estudiaron 100 mujeres en el tercer trimestre de embarazo en el Hospital San Vicente de Paul de la ciudad de Ibarra en la provincia de Imbabura-Ecuador. Se realizó la medición de peso y talla para el cálculo del índice de masa corporal. Se les aplicó una encuesta de consumo de alimentos y tomó una muestra de sangre para medir los niveles de lípidos circulantes mediante métodos enzimáticos colorimétricos. Resultados: se observó un incremento de los lípidos sanguíneos los cuales se relacionan con la frecuencia de consumo de grasas. Hubo una relación entre el HDL-colesterol y el LDL-colesterol con el consumo de grasas según el índice de masa corporal. Conclusiones: durante los controles obstétricos se debe evaluar la dieta de la embarazada y reforzar la necesidad de disminuir el consumo de grasas e incrementar el consumo de verduras, legumbres y cereales. La cuantificación periódica del perfil lipídico de las gestantes constituye una buena herramienta para el control de los lipídicos cuando estos superen los niveles fisiológicos, contribuyendo en un adecuado control prenatal(AU)

Introduction: Pregnancy is a condition that involves a metabolic adaptation to meet the requirements of the developing fetus. During gestation circulating lipids increase, leading to agrowth in lipid peroxidation. Under normal conditions, this phenomenon is offset by an increase in antioxidant systems. Objective: Compare the lipid profile in pregnant women according to body mass index and frequency of fat intake. Methods: A hundred women were studied in their third trimester of pregnancy. Weight and height were measuredto calculate body mass index. A survey on food consumption was appliedand blood samples were taken to measure levels of circulating lipids by enzymatic colorimetric methods. Results: An increase in blood lipids is observedrelated to the frequency of fat consumption. A ratio of HDL-cholesterol and LDL-cholesterol fat intake was found by the body mass index. Conclusions: During controls, obstetricians should evaluate the pregnant diet and reinforce the need to reduce fat intake and increase consumption of vegetables, legumes and cereals. The periodic quantification of the lipid profile of pregnant women is good tool to control lipid when they exceed physiological levels, contributing to an adequate prenatal control(AU)

Effect of consumption of tree tomato juice (Cyphomandra betacea) on lipid profile and glucose con centrations in adults with hyperlipidemia, Ecuador.

In this work the effect of consumption of tree tomato juice (Cypho-mandra betacea) was evaluated on nutritional and biochemical parameters in 54 volunteers (44 women and 10 men) aged 45 ±8 years-Ecuador. A nutritional and biochemical evaluation was performed in volunteers; then they were invited to drink tree tomato juice (IOOg of fruit in 150 ml of water) daily for 6 weeks. Finished these 6 weeks, volunteers were nutritional and biochemical evaluated again. 67% abdominal obesity was found, decreasing at 53% after drinking the established dosage of juice. 87% of the volunteers before treatment, showed -hypercholesterolemia, 40.7% and 46.3% had hypertriglyceridemia and elevated LDL, respectively and 18.5% glucose concentrations between 98-130 mg/dL. These values decrease significantly in this group after drinking tomato juice. In ge- neral, Total Cholesterol, LDL and glucose concentrations decrease significantly after drinking tree tomato juice in all the voluntaries with or without overweight. There is no change in HDL concentrations. The consumption of tree tomato juice did not affect the activity of alanine aminotransferase or aspartate aminotransferase enzymes either creatinine, urea and uric acid concentrations, neither blood pressure suggesting that does not affect renal or liver function. These results indicate that consumption of tree tomato juice for six weeks appears to have a lipid-lowering and modulating effect on glucose metabolism, suggesting C betacea as one of the high Andean fruits nutraceutical potential. However, this issue should be investigated in more detail.

Nutritional Status and Lipid Profile in HIV-Infected Adults.

In the last decades, there have been many reports of HIV infection and abnormalities in lipid metabolism and cardiovascular disease (CVD). This study aims at describing the nutritional status of HIV-infected adults and its relation to lipid profile through traditional [total cholesterol (TC), HDL cholesterol (HDL), triglycerides (TG), non-HDL cholesterol and LDL cholesterol (LDL)] and other parameters [Apolipoprotein B (ApoB), fibrinogen, and high sensitive-C-reactive protein (hs-CRP)]. A cross-sectional descriptive study was performed. Body mass index (BMI) was calculated and references were taken from WHO. TC, HDL, TG and glucose were determined and non-HDL cholesterol and LDL were calculated. ApoB and fibrinogen were determined by quantitative radial immunodiffusion on agar plates (Diffuplate,Biocientífica SA,Argentina) and hs-CRP by immunoturbidimetric test. Qualitative variables were compared with the Chi-square test or Fisher's exact test. Quantitative variables were compared applying parametrics or nonparametric tests. Pearson test for correlations. Software SPSS 17.0. 97 patients were analyzed: 69.1% were men. 80% were on antiretroviral treatment. Average (SD) BMI was 24.3 (4.1) kg/m(2). 29.4% were overweight and 5.9% obese. Patients with a BMI ≥25.0 kg/m(2) presented significantly higher levels of TG, ApoB and glycemia than well-nourished people [246.1(169.0) vs. 142.9(78.4) mg/dL;p=0.029, 198.6(69.3) vs. 126.4(50.6) mg/dL;p=0.01 and 100 (3.2) vs. 90.2 (6.9) mg/dL;p=0.008 resp.] and a significantly decreased HDL [37.2(1.5) vs. 49.8(10.4) mg/dL;p<0.01]. No statistically significant correlation was found between ApoB and non-HDL (p=0,063). There was no evidence that there is a direct relation between Apo B and the other lipid parameters. The potential increase in CVD in this group of patients, would be related to the higher levels of TG, ApoB and overweight/obesity. Nutritional education is needed to promote a healthy weight to warn against the risk of cardiovascular disease.

Decaffeinated green tea extract rich in epigallocatechin-3-gallate improves insulin resistance and metabolic profiles in normolipidic diet--but not high-fat diet-fed mice.

Supplementation with epigallocatechin-3-gallate (EGCG), which restores metabolic profiles, has been proposed as an option for preventing and treating obesity. We investigated whether decaffeinated green tea extract rich in EGCG, attenuates high-fat diet (HFD)-induced metabolic alterations in Swiss mice. The mice were maintained on either a control diet (CD) or HFD for 8 weeks and supplemented with either a placebo or EGCG (50mg/kg/day). Body weight, serum lipid profiles, cytokine protein expression, and content in epididymal (EPI) and retroperitoneal (RET) adipose tissues, and adipocyte area were measured. The body weights of HFD + placebo-fed mice were increased compared with those of HFD + EGCG-fed mice (28 and 21%, respectively), whereas the body weights of CD + EGCG-fed mice were decreased 16% compared with those of the CD + placebo group. Serum triglyceride levels were decreased 32% in the CD + EGCG group compared with the CD + placebo group. Compared with the CD + placebo group, increased phosphorylation of AMPK and hormone-sensitive lipase in EPI and RET, respectively, was found in the CD + EGCG group. Increased acetyl-CoA carboxylase phosphorylation was observed in both adipose tissues. In addition, TNF-α and IL-10 levels in EPI and adiponectin levels were higher in the CD + EGCG group than in the CD + placebo group. TNF-α levels were lower in the HFD + EGCG group than in the HFD + placebo group. Furthermore, the CD + EGCG group exhibited a lower adipocyte area than the CD + placebo group. These indicate that the effects of decaffeinated green tea extract on body mass may be related to the crosstalk between lipolytic and inflammatory pathways in normolipidic diet-fed mice but not in HFD-fed mice.

Salicylic acid elicitation during cultivation of the peppermint plant improves anti-diabetic effects of its infusions.

Peppermint (Mentha piperita) infusions represent an important source of bioactive compounds with health benefits, which can be enhanced by applying salicylic acid (SA) during plant cultivation. The aim of this study was to evaluate the effect of SA (0, 0.5 and 2 mM) during peppermint cultivation on the chemical profile of saponins and alkaloids, as well as the anti-diabetic properties of the resulting infusions. The results showed that a 2 mM SA treatment significantly improved the chemical profiles of the infusions. Furthermore, the administration of 2 mM SA-treated peppermint infusions for 4 weeks to a high-fat diet/streptozotocin-induced diabetic rats decreased serum glucose levels (up to 25%) and increased serum insulin levels (up to 75%) as compared with the diabetic control. This can be related to the observed protection on pancreatic ß-cells. Furthermore, 0.5 and 2 mM SA-treated peppermint infusions decreased LDL (24 and 47%, respectively) and increased HDL levels (18 and 37%, respectively). In addition, all groups treated with peppermint infusions had lower serum and liver triglyceride contents, where 2 mM SA peppermint infusion showed the highest effect (44% and 56%, respectively). This is probably caused by its higher capacity to inhibit pancreatic lipase activity and lipid absorption. Moreover, SA-treated peppermint infusions improved the steatosis score in diabetic rat liver and decreased serum transaminase levels, probably as a result of the increase in steroidal saponins and alkaloids, such as trigonellin. Therefore, the application of 2 mM SA during cultivation of peppermint could be used to improve the anti-diabetic properties of peppermint infusions.

Medium-chain dicarboxylic acylcarnitines as markers of n-3 PUFA-induced peroxisomal oxidation of fatty acids.

SCOPE: Omega-3 polyunsaturated fatty acids (n-3 PUFA) found in fish oil activate PPAR-α, stimulate peroxisomal fatty acid (FA) ß-oxidation and prevent impairments on glucose homeostasis. METHODS AND RESULTS: Glucose metabolism and FA oxidation were studied in C57/Bl6 mice fed with diets containing either 3.6 and 31.5% fish oil or lard. To assess the effects of peroxisomal proliferation on FA oxidation independent of n-3 PUFA intake, mice were treated with the PPAR-α agonist WY-14643. n-3 PUFA-fed mice were protected from glucose intolerance and dyslipidemia compared to animals fed a lard-based high-fat diet. Most importantly, mice fed on the hyperlipidic diet based on fish oil as well as the WY-14643 treated mice showed twofold increase of odd, medium-chain, dicarboxylic acylcarnitines in the liver suggesting that not only ß-oxidation, but also α- and ω-oxidation of FA were increased. Finally, an oxidation assay using liver homogenates and palmitic acid as substrate revealed an over tenfold increased production of similar acylcarnitines, indicating that FA are their precursors. CONCLUSION: This study shows at the metabolite level that peroxisome proliferation induced either by fish oil or WY-14643 is associated with increased α- and ω-oxidation of FA producing specific acylcarnitines that can be utilized as biomarkers of peroxisomal FA oxidation.