Spirulina liquid extract prevents metabolic disturbances and improves liver sphingolipids profile in hamster fed a high-fat diet.

PURPOSE: Metabolic syndrome is characterized by hyperglycemia, hyperlipemia and exacerbated oxidative stress. The aim of the study was to determine whether Spirulysat®, a Spirulina liquid extract (SLE) enriched in phycocyanin, would prevent metabolic abnormalities induced by high-fat diet. METHODS: The effect of acute SLE supplementation on postprandial lipemia and on triton-induced hyperlipidemia was studied in hamster fed control diet (C). The effect of chronic SLE supplementation on lipid content in plasma, liver and aorta, and on glycemia and oxidative stress was studied in hamster fed control (C) or high-fat diet (HF) for two weeks and then treated with SLE for two weeks (CSp and HFSp) or not (C and HF). RESULTS: The acute SLE supplementation lowered plasma cholesterol and non-esterified fatty acid concentrations after olive oil gavage (P < 0.05) in CSp, while no effect was observed on triglyceridemia. HFD increased plasma MDA, basal glycemia, triglyceridemia, total plasma cholesterol, VLDL, LDL and HDL cholesterol, ceramide, sphingomyelin and glucosylceramide content in liver in HF compared to C (P < 0.05). SLE did not affect SOD and GPx activities nor total antioxidant status in HFSp group but lowered glycemia, glucoceramide and cholesterol in liver and cholesterol in aorta compared to HF (P < 0.05). SLE also decreased HMGCoA and TGF-ß1 gene expression in liver (P < 0.05) and tended to lower G6Pase (P = 0.068) gene expression in HFSp compared to HF. CONCLUSION: Although 2-week SLE supplementation did not affect oxidative stress, it protected from hyperglycemia and lipid accumulation in liver and aorta suggesting a protective effect against metabolic syndrome.

Dietary Arginine Supplementation during Gestation and Lactation Increases Milk Yield and Mammary Lipogenesis in Rats.

BACKGROUND: Arginine, an essential amino acid during the reproductive period, has been shown to enhance lactation performances in livestock. Whether it could help mothers with breastfeeding difficulties is not known. OBJECTIVES: This study aimed to determine whether dietary arginine supplementation would enhance milk production in rat dams nursing large 12-pup litters and, if so, what mechanisms are involved. METHODS: In 3 series of experiments, differing in dam killing timing, 59 primiparous, pregnant Sprague-Dawley rats (mean ± SD weight: 254 ± 24.7 g) were randomly assigned to receive either 1) an AIN-93G diet supplemented with l-arginine at 2.0% (ARG diet), through lactation and gestation (AGL group); 2) a control AIN-93G diet including at 3.5% an isonitrogenous mix of amino acids that are not essential for lactation (MA diet), during gestation and lactation (MA group); or 3) the MA diet during gestation and the ARG diet during lactation (AL group). Milk flow was measured using deuterated water enrichment between days 11 and 18. Plasma hormones and mammary expression of genes involved in lactation were measured using ELISA and qRT-PCR, respectively, at lactation days 12, 18, or 21 in the 3 experiments. Data were analyzed by ANOVA. RESULTS: Dam food intake, pup weight gain, milk flow normalized to dam weight, and milk fat concentration were 17%, 9%, 20%, and 20% greater in the AGL group than in the MA group, respectively (P < 0.05). Genes involved in lipogenesis and lipid regulation were overexpressed ≤2.76-fold in the mammary gland of AGL dams compared with MA dams (P < 0.05) and plasma leptin concentration was 39% higher (P = 0.008). Milk flow and composition and mammary gene expression of the AL group did not differ from those of the MA group, whereas milk fat concentration and flow were 26% and 37% lower than in the AGL group, respectively. CONCLUSIONS: Arginine supplementation during gestation and lactation enhances milk flow and mammary lipogenesis in rats nursing large litters.

Omega 3 Improves Both apoB100-containing Lipoprotein Turnover and their Sphingolipid Profile in Hypertriglyceridemia.

CONTEXT: Evidence for an association between sphingolipids and metabolic disorders is increasingly reported. Omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) improve apolipoprotein B100 (apoB100)-containing lipoprotein metabolism, but their effects on the sphingolipid content in lipoproteins remain unknown. OBJECTIVES: In subjects with hypertriglyceridemia, we analyzed the effect of n-3 LC-PUFAs on the turnover apoB100-containing lipoproteins and on their sphingolipid content and looked for the possible association between these lipid levels and apoB100-containing lipoprotein turnover parameters. METHODS: Six subjects underwent a kinetic study before and after n-3 supplementation for 2 months with 1 g of fish oil 3 times day containing 360 mg of eicosapentaenoic acid (EPA) and 240 mg of docosahexaenoic acid (DHA) in the form of triglycerides. We examined apoB100-containing lipoprotein turnover by primed perfusion labeled [5,5,5-2H3]-leucine and determined kinetic parameters using a multicompartmental model. We quantified sphingolipid species content in lipoproteins using mass spectrometry. RESULTS: Supplementation decreased very low-density lipoprotein (VLDL), triglyceride, and apoB100 concentrations. The VLDL neutral and polar lipids showed increased n-3 LC-PUFA and decreased n-6 LC-PUFA content. The conversion rate of VLDL1 to VLDL2 and of VLDL2 to LDL was increased. We measured a decrease in total apoB100 production and VLDL1 production. Supplementation reduced the total ceramide concentration in VLDL while the sphingomyelin content in LDL was increased. We found positive correlations between plasma palmitic acid and VLDL ceramide and between VLDL triglyceride and VLDL ceramide, and inverse correlations between VLDL n-3 LC-PUFA and VLDL production. CONCLUSION: Based on these results, we hypothesize that the improvement in apoB100 metabolism during n-3 LC-PUFA supplementation is contributed to by changes in sphingolipids.

Impact of Fenugreek on Milk Production in Rodent Models of Lactation Challenge.

Fenugreek, a herbal remedy, has long been used as galactologue to help mothers likely to stop breastfeeding because of perceived insufficient milk production. However, few studies highlight the efficacy of fenugreek in enhancing milk production. The aims of our study were to determine whether fenugreek increased milk yield in rodent models of lactation challenge and if so, to verify the lack of adverse effects on dam and offspring metabolism. Two lactation challenges were tested: increased litter size to 12 pups in dams fed a 20% protein diet and perinatal restriction to an 8% protein diet with eight pups' litter, with or without 1 g.kg-1.day-1 dietary supplementation of fenugreek, compared to control dams fed 20% protein diet with eight pups' litters. Milk flow was measured by the deuterium oxide enrichment method, and milk composition was assessed. Lipid and glucose metabolism parameters were assessed in dam and offspring plasmas. Fenugreek increased milk production by 16% in the litter size increase challenge, resulting in an 11% increase in pup growth without deleterious effect on dam-litter metabolism. Fenugreek had no effect in the maternal protein restriction challenge. These results suggest a galactologue effect of fenugreek when mothers have no physiological difficulties in producing milk.

Spirulina Liquid Extract Protects against Fibrosis Related to Non-Alcoholic Steatohepatitis and Increases Ursodeoxycholic Acid.

Non-alcoholic steatohepatitis (NASH) is characterized by an excess of lipids and oxidative stress in the liver. Spirulina was reported to possess hypolipemic and antioxidative effects and might counteract NASH development. C57Bl/6J mice were fed a western diet (WD) during 25 weeks with or without spirulina liquid extract (SLE) at 2 different doses (WDS1 and WDS2 groups) in drinking water. Liver histology, inflammation, and oxidative stress were assessed as well as glucose tolerance status, lipid metabolism, and gallbladder bile acid profile. WDS2 gained significantly less weight than WD. Liver weight-to-body weight ratio and plasma alanine aminotransferase were significantly lower in WDS2 mice. A reduced liver fibrosis and NFκBp65 protein expression were measured in the supplemented group as a lower accumulation of superoxide anion, nitric oxide, and thiobarbituric reactive substances. WDS2 mice showed also a preserved glucose tolerance, a strong decrease of plasma cholesterol, and a significant increase of gallbladder ursodeoxycholic acid and ß-muricholic acid. Our findings demonstrate a protective effect of SLE against WD induced NASH that is related to less inflammation and oxidative stress, a preserved glucose tolerance, and less hepatotoxic bile acid profile.