Laura González-Torres

Liver oxidation and inflammation in Fa/Fa rats fed glucomannan/ spirulina-surimi

The effect of high-fat squid-surimi diets enriched in glucomannan or glucomannan-spirulina on lipemia, liver glutathione status, antioxidant enzymes and inflammation biomarkers was determined in Zucker Fa/Fa rats. Groups of eight rats each received for 7weeks the squid-surimi control (C), glucomannan-enriched squid-surimi (G) and glucomannan-spirulina enriched squid-surimi (GS). Liver weight, cytochrome P450 7A1 expression and cholesterolemia were decreased in G and GS vs. C, improving glutathione red-ox index (p<0.05). G also showed increased glutathione reductase (GR) levels vs. C, but reduced the endothelial (eNOS) and increased the inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-α) levels (p<0.05). The GS diet improved superoxide dismutase, catalase, glutathione peroxidase and GR activities and eNOS, iNOS and TNF-α levels (p<0.05). The glucomannan enriched surimi-diet induced hypocholesterolemic, antioxidant and proinflammatory effects, while the addition of 3g/kg spirulina kept those hypocholesterolemic and antioxidant effects but reduced the inflammation observed.

Effects of restructured pork containing Himanthalia elongata on adipose tissue lipogenic and lipolytic enzyme expression of normo- and hypercholesterolemic rats.

Background: Inclusion of seaweeds in restructured pork (RP) would improve meat health properties. Aim: The aim was to determine the effects of RP containing Himanthalia elongata on growth, organ weight, cholesterolemia, and expression of lipoprotein lipase (LPL), acetyl CoA carboxylase (ACC), fatty acid synthase (FAS), and hormone-sensitive lipase (HSL) in adipose tissue of Wistar rats. Methods: The control group (C) consumed control RP, and the seaweed group (SS) consumed RP with 5% Himanthalia elongata. Animals on cholesterol-enriched diets (CholC, CholSS) consumed their corresponding basal diets with supplementary cholesterol (2.43%) plus cholic acid (0.49%) as hypercholesterolemic agents. Results: Seaweed inclusion did not modify cholesterolemia but reduced (p < 0.01) the hypercholesterolemic effect of dietary cholesterol plus cholic acid. CholC rats presented lower (p < 0.05) adipose fat and weight than C rats. Cholesterol feeding affected HSL, ACC, and FAS expression (p < 0.05), while alga consumption influenced HSL and ACC (p < 0.05). LPL was not significantly affected by both factors. CholSS rats showed decreased HSL and FAS (p < 0.05) but increased ACC (p < 0.05) expression compared with CholC rats. Conclusion:Himanthalia RP partially blocked the dietary hypercholesterolemic effect and changed the lipogenic/lipolytic enzyme expression, reducing the wasting effect of hypercholesterolemia on adipose tissue in rats.

Beneficial effects of chocolate on cardiovascular health

Since ancient times, numerous health beneficial effects have been attributed to chocolate, closing up its consumption to a therapeutic use. The present study reviews some relevant studies about chocolate (and its bioactive compounds) on some cardiovascular risk factors and stresses the need of future studies. The consumption of cocoa/ chocolate (i) increases plasma antioxidant capacity, (ii) diminishes platelet function and inflammation, and (iii) decreases diastolic and systolic arterial pressures. Data currently available indicate that daily consumption of cocoa-rich chocolate (rich in polyphenols) may at least partially lower cardiovascular disease risk. Further studies are required in order to establish the bioavailability and mechanisms of action of bioactive compounds in chocolate. The study of the interaction of chocolate and its components with candidate genes will also supply necessary information regarding the individuals best suited to benefit from a potential cardiovascular disease treatment with chocolate.

Glucomannan- and glucomannan plus spirulina-enriched pork affect liver fatty acid profile, LDL receptor expression and antioxidant status in Zucker fa/fa rats fed atherogenic diets

ABSTRACT We evaluated the effects of glucomannan or glucomannan plus spirulina-restructured pork (RP) on liver fatty acid profile, desaturase/elongase enzyme activities and oxidative status of Zucker fa/fa rats for seven weeks. Control (C), glucomannan (G) and glucomannan/spirulina (GS)-RP; HC (cholesterol-enriched control), HG and HGS (cholesterol-enriched glucomannan and glucomannan/spirulina-RP) experimental diets were tested. Increased metabolic syndrome markers were found in C, G and GS rats. Cholesterol feeding increased liver size, fat, and cholesterol and reduced antioxidant enzyme levels and expressions. Cholesterolemia was lower in HG and HGS than in HC. GS vs. G showed higher stearic but lower oleic levels. SFA and PUFA decreased while MUFA increased by cholesterol feeding. The arachidonic/linoleic and docosahexaenoic/alpha-linolenic ratios were lower in HC, HG, and HGS vs. C, G, and GS, respectively, suggesting a delta-6-elongase-desaturase system inhibition. Moreover, cholesterol feeding, mainly in HGS, decreased low-density-lipoprotein receptor expression and the delta-5-desaturase activity and increased the delta-9-desaturase activity. In conclusion, the liver production of highly unsaturated fatty acids was limited to decrease their oxidation in presence of hypercholesterolaemia. Glucomannan or glucomannan/spirulina-RP has added new attributes to their functional properties in meat, partially arresting the negative effects induced by high-fat-high-cholesterol feeding on the liver fatty acid and antioxidant statuses.

GLUCOMANNAN AND GLUCOMANNAN PLUS SPIRULINA-ENRICHED SQUID-SURIMI ADDED TO HIGH SATURATED DIET AFFECT GLYCEMIA, PLASMA AND ADIPOSE LEPTIN AND ADIPONECTIN LEVELS IN GROWING FA/FA RATS.

Type 2 diabetes is a very prevalent chronic disease. Among dietary factors for its prevention and treatment, interest has grown in satiating fibre (konjac glucomannan) and spirulina. Our previous studies suggest that glucomannan itself and/or in conjunction to spirulina displayed hypolipemic and antioxidant effects when incorporated to squid surimi as functional ingredients. The present study aims to determine whether glucomannan- enriched or glucomannan plus spirulina-enriched squid-surimi improve plasma glucose and insulin levels in Zucker fa/fa rats fed a high saturated fat diet. Twenty four growing rats, divided into three groups, were given modified AIN-93M diets for seven weeks: 30% squid-surimi control diet (C), 30% glucomannan-enriched squid-surimi diet (G) and 30% glucomannan plus spirulina-enriched squid-surimi diet (GS). All rats became hyperglycemics and hyperinsulinemics, but G and GS diets induced significantly lower glucose levels (20%; p < 0.05) but did not modify insulinemia with respect to C diet. GS animals showed higher HOMA-D (p < 0.05) than C ones suggesting increased insulin availability. Plasma leptin and adiponectin decreased in G and GS vs. C group (p < 0.05). Adipose adiponectin increased significantly in G and GS vs. C rats (16-20 times, p < 0.01). Leptin in adipose tissue was higher in GS vs. G group (p < 0.05). In conclusion, both glucomannan-diets were able to reduce hyperglycemia and increase adipose tissue adiponectin levels in fa/fa rats, suggesting an anti-hypertrophic and insulin-sensitizing adipokine effect in this tissue. Spirulina inclusion increased insulin availability. Although results are promising, the utility of consuming glucomannan surimis as part of usual diets demands future studies.

Glucomannan or Glucomannan Plus Spirulina-Enriched Squid-Surimi Diets Reduce Histological Damage to Liver and Heart in Zucker fa/fa Rats Fed a Cholesterol-Enriched and Non-Cholesterol-Enriched Atherogenic Diet

Glucomannan-enriched squid surimi improves cholesterolemia and liver antioxidant status. The effect of squid surimi enriched with glucomannan or glucomannan plus spirulina on liver and heart structures and cell damage markers was tested in fa/fa rats fed highly saturated-hyper-energetic diets. Animals were fed 70% AIN-93M rodent diet plus six versions of 30% squid surimi for 7 weeks: control (C), glucomannan (G), and glucomannan plus spirulina (GS). The cholesterol-control (HC), cholesterol-glucomannan (HG), and cholesterol-glucomannan plus spirulina (HGS) groups were given similar diets that were enriched with 2% cholesterol and 0.4% cholic acid. G and GS diets versus C diet significantly inhibited weight gain and lowered plasma alanine aminotransferase and aspartate aminotransferase, liver steatosis, lipogranulomas, and total inflammation and alteration scores. The hypercholesterolemic agent significantly increased the harmful effects of the C diet. Liver weight, the hepatosomatic index, all damage markers, and total histological scoring rose for HC versus C (at least P < .05). The addition of glucomannan (HG vs. HC) improved these biomarkers, and non-additional effects from spirulina were observed except for the total liver alteration score. In conclusion, glucomannan and glucomannan plus spirulina blocked the highly saturated-hyper-energetic diet negative effects both with and without added cholesterol. Results suggest the usefulness of including these functional ingredients in fish products.