Effects of Nori- and Wakame-enriched meats with or without supplementary cholesterol on arylesterase activity, lipaemia and lipoproteinaemia in growing Wistar rats

The preventive and therapeutic consumption of meat enriched with carob fruit extract, rich in phenolic compounds, improves colonic antioxidant status in late-stage T2DM rats

Oxidative stress is prevalent in Type 2 Diabetes Mellitus (T2DM) and has been associated with high meat consumption. Carob Fruit Extract (CFE) contains phenolic compounds, making it a suitable functional ingredient. Current study aims to evaluate the effect of CFE-enriched meat (CFE-meat) consumption on the antioxidant status of proximal and distal colon, and its relationship with fecal phenolic compounds in late-stage T2DM rats. Three groups of eight rats were studied: 1) D, fed control-meat; 2) ED, fed CFE-meat since the beginning of the study; 3) DE, fed CFE-meat after confirming T2DM. CFE-meat consumption reduces colonic oxidative stress mainly in the proximal section and helps to ameliorate glutathione metabolism and antioxidant score. Difference between ED and DE groups were associated with colon homeostasis and T2DM progression suggesting greater fermentation but lower absorption in the DE group. CFE appears as a promising tool to improve the antioxidant status observed in late-stage T2DM.

Macroalgae-derived bioactive compounds for functional food and pharmaceutical applications-a critical review

The rising demand for global food resources, combined with an overreliance on land-based agroecosystems, poses a significant challenge for the sustainable production of food products. Macroalgae cultivation is a promising approach to mitigate impending global food insecurities due to several key factors: independence from terrestrial farming, rapid growth rates, unique biochemical makeup, and carbon capture potential. Furthermore, macroalgae are rich in vitamins, minerals, essential amino acids, polyunsaturated fatty acids and fiber, demonstrating significant potential as sustainable alternatives for enhancing dietary diversity and fulfilling nutritional requirements. This review provides an overview of the nutritional composition and functional properties of commercially cultivated macroalgae species, with emphasis on their viability as value additions to the functional food market. Furthermore, the review discusses the technological aspects of integrating macroalgae into food products, covering both innovative solutions and existing challenges. Macroalgae, beyond being nutritional powerhouses, contain a plethora of bioactive compounds with varied biological activities, including anti-diabetic, anti-cancer, cardioprotective, and neuroprotective properties, making them excellent candidates in developing novel pharmaceuticals. Thus, this review also summarizes the pharmaceutical applications of macroalgae, identifies research gaps and proposes potential strategies for incorporating macroalgae-derived bioactive compounds into therapeutic products.

Silicon as a Functional Meat Ingredient Improves Jejunal and Hepatic Cholesterol Homeostasis in a Late-Stage Type 2 Diabetes Mellitus Rat Model

Silicon included in a restructured meat (RM) matrix (Si-RM) as a functional ingredient has been demonstrated to be a potential bioactive antidiabetic compound. However, the jejunal and hepatic molecular mechanisms by which Si-RM exerts its cholesterol-lowering effects remain unclear. Male Wistar rats fed an RM included in a high-saturated-fat high-cholesterol diet (HSFHCD) combined with a low dose of streptozotocin plus nicotinamide injection were used as late-stage type 2 diabetes mellitus (T2DM) model. Si-RM was included into the HSFHCD as a functional food. An early-stage TD2M group fed a high-saturated-fat diet (HSFD) was taken as reference. Si-RM inhibited the hepatic and intestinal microsomal triglyceride transfer protein (MTP) reducing the apoB-containing lipoprotein assembly and cholesterol absorption. Upregulation of liver X receptor (LXRα/β) by Si-RM turned in a higher low-density lipoprotein receptor (LDLr) and ATP-binding cassette transporters (ABCG5/8, ABCA1) promoting jejunal cholesterol efflux and transintestinal cholesterol excretion (TICE), and facilitating partially reverse cholesterol transport (RCT). Si-RM decreased the jejunal absorptive area and improved mucosal barrier integrity. Consequently, plasma triglycerides and cholesterol levels decreased, as well as the formation of atherogenic lipoprotein particles. Si-RM mitigated the dyslipidemia associated with late-stage T2DM by Improving cholesterol homeostasis. Silicon could be used as an effective nutritional approach in diabetic dyslipidemia management.

Silicon-enriched meat positively improves plasma lipidaemia and lipoproteinaemia, LDLr, and insulin capability and the signalling pathway induced by an atherogenic diet in late-stage type 2 diabetes mellitus rats

The impact of silicon as a functional ingredient in restructured meat (RM) on lipoprotein composition, metabolism, and oxidation on type 2 diabetes mellitus (T2DM) markers has never been studied. This study aims to evaluate the effect of silicon-enriched-meat consumption on lipidaemia, lipoprotein profile and metabolism, plasma arylesterase, and TBARS and their relationships with glycaemia, insulinaemia, and insulin-signaling markers in late-stage-T2DM rats fed a high-saturated-fat-high-cholesterol (HSFHC) diet. Saturated-fat diets with or without added cholesterol were formulated by mixing a 70% purified diet with 30% freeze-dried RM with or without added silicon. Three groups of seven Wistar rats each were tested. The ED group received the control RM in the framework of a high-saturated-fat diet as early-stage T2DM control. The other two groups received streptozotocin-nicotinamide administration together with the HSFHC diet containing the control RM (LD) or silicon-enriched RM (LD-Si). Scores were created to define the diabetic trend and dyslipidaemia. The ED rats showed hyperglycaemia, hyperinsulinaemia, hypertriglyceridaemia, and triglyceride-rich-VLDLs, suggesting they were in early-stage T2DM. LD rats presented hyperglycaemia, hypoinsulinaemia, and reduced HOMA-beta and insulin signaling markers typical of late-stage T2DM along with hypercholesterolaemia and high amounts of beta-VLDL, IDL, and LDL particles and low arylesterase activity. All these markers were significantly (p < 0.05) improved in LD-Si rats. The diabetic trend and diabetes dyslipidaemia scores showed a high and significant correlation (r = 0.595, p < 0.01). Silicon-enriched-meat consumption counterbalances the negative effects of HSFHC diets, functioning as an active hypolipemic, antioxidant, and antidiabetic dietary ingredient in a T2DM rat model, delaying the onset of late-stage diabetes.

Functional Meat Products as Oxidative Stress Modulators: A Review

High meat consumption has been associated with increased oxidative stress mainly due to the generation of oxidized compounds in the body, such as malondialdehyde, 4-hydroxy-nonenal, oxysterols, or protein carbonyls, which can induce oxidative damage. Meat products are excellent matrices for introducing different bioactive compounds, to obtain functional meat products aimed at minimizing the pro-oxidant effects associated with high meat consumption. Therefore, this review aims to summarize the concept and preparation of healthy and functional meat, which could benefit antioxidant status. Likewise, the key strategies regarding meat production and storage as well as ingredients used (e.g., minerals, polyphenols, fatty acids, walnuts) for developing these functional meats are detailed. Although most effort has been made to reduce the oxidation status of meat, newly emerging approaches also aim to improve the oxidation status of consumers of meat products. Thus, we will delve into the relation between functional meats and their health effects on consumers. In this review, animal trials and intervention studies are discussed, ascertaining the extent of functional meat products' properties (e.g., neutralizing reactive oxygen species formation and increasing the antioxidant response). The effects of functional meat products in the frame of diet-gene interactions are analyzed to 1) discover target subjects that would benefit from their consumption, and 2) understand the molecular mechanisms that ensure precision in the prevention and treatment of diseases, where high oxidative stress takes place. Long-term intervention-controlled studies, testing different types and amounts of functional meat, are also necessary to ascertain their positive impact on degenerative diseases.

Brown Seaweeds for the Management of Metabolic Syndrome and Associated Diseases

Metabolic syndrome is characterized by the coexistence of different metabolic disorders which increase the risk of developing type 2 diabetes mellitus and cardiovascular diseases. Therefore, metabolic syndrome leads to a reduction in patients' quality of life as well as to an increase in morbidity and mortality. In the last few decades, it has been demonstrated that seaweeds exert multiple beneficial effects by virtue of their micro- and macronutrient content, which could help in the management of cardiovascular and metabolic diseases. This review aims to provide an updated overview on the potential of brown seaweeds for the prevention and management of metabolic syndrome and its associated diseases, based on the most recent evidence obtained from in vitro and in vivo preclinical and clinical studies. Owing to their great potential for health benefits, brown seaweeds are successfully used in some nutraceuticals and functional foods for treating metabolic syndrome comorbidities. However, some issues still need to be tackled and deepened to improve the knowledge of their ADME/Tox profile in humans, in particular by finding validated indexes of their absorption and obtaining reliable information on their efficacy and long-term safety.

Pigments Content (Chlorophylls, Fucoxanthin and Phycobiliproteins) of Different Commercial Dried Algae

Algae are a complex, polyphyletic group of organisms, affordable and naturally rich in nutrients, but also valuable sources of structurally diverse bioactive substances such as natural pigments. The aim of this work was to evaluate the polar and non-polar pigment contents of different commercial dried algae (brown: Himanthalia elongata, Undaria pinnatifida, Laminaria ochroleuca; red: Porphyra spp.; and a blue-green microalga: Spirulina spp.). The pigment extraction was carried out using different solvents (100% methanol, 100% methanol acid free, 100% ethanol, 90% acetone, N,N-dimethylformamide, dimethyl sulfoxide-water (4:1, v/v) and pH 6.8 phosphate buffer), selected according to their affinity for each class of pigments. Acetone proved to be an efficient solvent to extract chlorophylls from brown and red algae, but not from Spirulina spp. Porphyra spp. presented considerably higher levels of all pigments compared to brown algae, although Spirulina spp. presented significantly higher (p < 0.05) levels of chlorophylls, carotenoids and phycobiliproteins, compared to all macroalgae. The content of fucoxanthin extracted from the three brown algae was highly correlated to the carotenoid content. Within this group, Himanthalia elongata presented the highest fucoxanthin/total carotenoids ratio. Although the yield of extraction depended on the solvent used, the algae studied herein are an interesting source of pigments of great value for a wide range of applications.

Can Carob-Fruit-Extract-Enriched Meat Improve the Lipoprotein Profile, VLDL-Oxidation, and LDL Receptor Levels Induced by an Atherogenic Diet in STZ-NAD-Diabetic Rats?

Carob fruit extract (CFE) has shown remarkable in vitro antioxidant properties and reduces postprandial hyperglycemia and hyperlipidemia in healthy animals. Development of functional meat products that contain bioactive components are presented as a great nutritional strategy. Until now, the effect of the consumption of restructured meat enriched with CFE in a murine model of diabetes has not been investigated. The objective of this study was to evaluate the effect on glycemia, lipemia, lipoprotein profile, Ldlr, arylesterase (AE), and very low-density lipoproteins (VLDL) and liver oxidation in streptozotocin-nicotinamide (STZ-NAD) growing Wistar diabetic rats fed restructured meat in the frame of a high cholesterol/high saturated-fat diet. In the present study, three groups (D, ED and DE) were fed cholesterol-enriched (1.4% cholesterol and 0.2% cholic acid) and high saturated-fat diets (50% of total energy from fats and 20.4% from saturated fatty acids). Rats were subjected to a STZ-NAD administration at the 3rd week. Group D did not receive CFE, while ED and DE rat groups received CFE before and after the diabetic induction, respectively. After eight weeks, D rats showed hyperglycemia and hypercholesterolemia, an increased amount cholesterol-enriched VLDL (β-VLDL), IDL and LDL particles and triglyceride-enriched HDL. ED and DE partially blocked the hypercholesterolemic induction with respect to D group (p < 0.001) and improved glycemia, cholesterol levels, lipoprotein profile, Ldlr, plasma AE activity and liver oxidation (p < 0.001). Fecal fat, moisture and excretion were higher while dietary digestibility was lower in ED and DE vs. D counterparts (p < 0.0014). In conclusion, CFE-enriched meat shows, for the first time, hypoglycemic and hypolipidemic effects in STZ-NAD animals fed high cholesterol/high saturated-fat diets. Likewise, it manages to reverse possible diabetes lipoprotein alterations if CFE-enriched meat is consumed before pathology development or improves said modifications if Type 2 Diabetes Mellitus is already established.

In vivo bioavailability of polyphenols from grape by-product extracts, and effect on lipemia of normocholesterolemic Wistar rats

BACKGROUND

The direct use of phenolic extracts from grape by-products can be useful when formulating functional food to improve consumer health. The use of phenolic extracts instead of pure polyphenols as an ingredient is relevant in this context. The present study investigated the bioavailability and absorption of polyphenols from grape by-product extracts and their health effect on cholesterolemia, by adding the extract (GE) to Wistar rats diet (50 g kg^-1 ) in vivo.

RESULTS

GE caused the appearance of (+)-catechin, myricetin and quercetic acid in plasma and liver. (+)-Catechin was the most abundant compound (6 μg mL^-1 in plasma and 0.7 μg mg^-1 protein in liver), whereas no phenolic compounds were detected in plasma or liver in the control group. Similarly, 3,4-hydroxyphenylacetic, a major product of polyphenol digestion, was detected in the plasma, liver and urine of the GE-group only. GE-group had significantly lower cholesterol level and lower total cholesterol/high-density lipoprotein ratio in plasma. Total bile acid content significantly increased in fecal matter after 24 h administration of the GE-enriched diet.

CONCLUSION

Grape extract polyphenols are partially bioavailable and showed improvement in lipid metabolism. Thus, the results suggest that GE is promising as a functional ingredient in the prevention of hypercholesterolemia. © 2018 Society of Chemical Industry.

Lipoprotein Profile in Aged Rats Fed Chia Oil- or Hydroxytyrosol-Enriched Pork in High Cholesterol/High Saturated Fat Diets

Restructuring pork (RP) by adding new functional ingredients, like Chia oil (one of the richest natural source of α-linolenic acid) or hydroxytyrosol (HxT) (potent antioxidant), both with hypolipidemic activities, is one of the strategies that may help to reduce the potential negative effects of high meat products consumption. The aim of this study was to evaluate the Chia oil- or HxT-enriched-RP effect on the lipoprotein profile of aged rats fed high-fat, high-energy, and cholesterol-enriched diets. RP samples were prepared by mixing lean pork and lard with or without Chia oil (152.2 g/kg fresh matter) or HxT (3.6 g/kg fresh matter). Diets were prepared by mixing a semisynthetic diet with freeze-dried RP. Groups of 1-year male Wistar rats were fed the following experimental diets for 8 weeks: C, control-RP diet; HC, cholesterol-enriched-RP diet; and Chia oil-RP (CHIA) and HxT, Chia oil- or hydroxytyrosol-RP, cholesterol-enriched diet. Plasma lipid, lipoprotein profile, SREBP-1c protein, and low-density lipoproteins (LDL) receptor gene (Ldlr) expressions were evaluated. Compared to C diet, the HC diet increased plasma cholesterol, triglycerides, free fatty acids, total lipids, and SREBP-1c expression, but reduced Ldlr expression and significantly modified the lipoprotein profile, giving rise to the presence of high levels of atherogenic cholesterol-enriched very low-density lipoproteins (VLDL) particles. Compared to the HC diet, the HxT diet did not produce significant changes in feed intake but it reduced the body weight. Chia oil and HxT partially arrested the negative effects of the high-fat, high-energy, and cholesterol-enriched meat-based diets on lipemia and lipoproteinemia, mostly by reducing the amount of cholesterol content in VLDL (60% and 74% less in CHIA and HxT vs. HC, respectively) and the VLDL total mass (59% and 63% less in CHIA and HxT vs. HC, respectively). Free fatty acids (FFA) significantly correlated with adipose tissue weight and VLDL total mass (both p < 0.05), and plasma triglycerides, phospholipids, total lipids, and SREBP-1c (all p < 0.001), suggesting the important role of FFA in lipoprotein metabolism. Results support the recommendation to include these ingredients in pork products addressed to reduce the presence of increased atherogenic particles in aged people at CVD risk consuming large amounts of pork.

Fucoidan Extracted from Undaria pinnatifida: Source for Nutraceuticals/Functional Foods

The importance of fucoidan as a functional ingredient in food, health products, and pharmaceutics is well-recognized due to its beneficial biological effects. Fucoidan is usually extracted from brown seaweeds, including Undaria pinnatifida. Fucoidan exhibits beneficial bio-activity and has antioxidant, anticancer, and anticoagulant properties. This review focuses on the biological activity of U. pinnatifida-derived fucoidan and investigates its structure⁻activity or fraction⁻activity relationship. It also describes several fucoidan extracts, along with their claimed anticancer effects. It aims to provide information and thoughts for future research such as the development of fucoidan into functional foods or nutraceuticals.

Histomorphological changes in the pancreas and kidney and histopathological changes in the liver in male Wistar rats on antiretroviral therapy and melatonin treatment

Combination antiretroviral therapy (cART) has shown to cause inflammation, cellular injury and oxidative stress, whereas melatonin has been successful in reducing these effects. The aim of the study was to determine potential morphometric changes caused by cART in combination with melatonin supplementation in human immunodeficiency virus (HIV)-free rats. Tissue samples (N = 40) of the pancreas, liver and kidney from a control (C/ART-/M-), cART group (C/ART + ), melatonin (C/M + ) and experimental group (ART+/M + ) were collected and stained with haematoxylin and eosin (H&E) and evaluated for histopathology. The pancreata were labelled with anti-insulin and anti-glucagon to determine α- and β-cell regions. Kidneys were stained with periodic acid Schiff (PAS) to measure the area, perimeter, diameter and radius of renal corpuscles, glomeruli and proximal convoluted tubules (PCTs). Blood tests were conducted to determine hepatotoxicity. No significant changes in histopathology were seen. Melatonin stimulated pancreatic islet abundance, as the number of islets per mm² was significantly higher in the C/M+ than in the C/ART-/M- and ART+/M+. Parameters of the renal corpuscle, glomeruli, renal space and PCTs were significantly lower in the C/ART+ compared to the other groups, thus cART may have caused tubular dysfunction or cellular damage. A significant increase in serum haemoglobin was observed in the C/ART+ compared to the C/ART-, which showed cART increases serum haemoglobin in the absence of immune deficiency. Serum lipids were significantly decreased in the C/M+ compared to the C/ART-, possibly due to the effect of melatonin on the decrease of lipolysis, decreasing effect on cholesterol absorption and stimulation of lipoprotein lipase (LPL) activity. In conclusion, we have demonstrated that melatonin stimulated α-cell production, increased the number of pancreatic islets and caused a decrease in total lipids, whereas cART increased serum haemoglobin and decreased various parameters of the nephron in an HIV-free rat model, suggestive of tubular dysfunction.

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

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 added to pork significantly block dietary cholesterol effects on lipoproteinemia, arylesterase activity, and CYP7A1 expression in Zucker fa/fa rats

Zucker fa/fa rats easily develop dyslipidemia and obesity. Restructured pork (RP) is a suitable matrix for including functional ingredients. The effects of glucomannan- RP or glucomannan plus spirulina-enriched RP on plasma lipid/lipoprotein levels, cytochrome P450 7A1 (CYP7A1) expression, and arylesterase activity in growing fa/fa rats fed high-energy, high-fat cholesterol-enriched diets were tested. Groups of six rats each received diet containing 15% control-RP (C), 15% glucomannan-RP diet (G), 15% glucomannan + spirulina-RP diet (GS), and same diets enriched with 2.4% cholesterol and 0.49% cholic acid (cholesterol-enriched control (HC), cholesterol-enriched glucomannan (HG), and cholesterol-enriched glucomannan + spirulina (HGS) diets) over a 7-week period. C diet induced obesity, severe hyperglycemia, moderate hypercholesterolemia, and hypertriglyceridemia. Those facts were not significantly modified by G or GS diets. G diet increased CYP7A1 expression but decreased the total cholesterol/high density lipoproteins (HDL)-cholesterol ratio (p < 0.05) vs. C diet. GS vs. G diet increased (p < 0.05) CYP7A1 expression. HC vs. C diet reduced food intake, body weight gain, and plasma glucose (p < 0.01) but increased cholesterolemia (p < 0.01), lipidemia (plasma cholesterol plus triglycerides) (p < 0.001), cholesterol/triglyceride ratio in very low density lipoproteins (VLDL), and HDL (p < 0.05), cholesterol transported by VLDL and intermediate density lipoproteins (IDL) + low density lipoproteins (LDL), total cholesterol/HDL-cholesterol ratio and CYP7A1 expression (at least p < 0.05). HG and HGS diets vs. HC noticeably reduced lipidemia (p < 0.001), normalized VLDL and IDL + LDL lipid composition, and increased CYP7A1 expression (p < 0.01) but did not modify the cholesterol/HDL-cholesterol ratio. HGS vs. HG decreased triglyceridemia, the triglyceride-glucose (TyG) index and increased arylesterase/HDL-cholesterol activity (p < 0.05). In conclusion, G- and GS-RP act as functional foods and notably blocked the dietary cholesterol effects. In addition, HGS-RP improved the glucomannan hypolipidemic effects, increased arylesterase/HDL-cholesterol activity, and decreased insulin resistance.

Application of seaweeds to develop new food products with enhanced shelf-life, quality and health-related beneficial properties

Edible seaweeds are a good source of antioxidants, dietary fibers, essential amino acids, vitamins, phytochemicals, polyunsaturated fatty acids, and minerals. Many studies have evaluated the gelling, thickening and therapeutic properties of seaweeds when they are used individually. This review gives an overview on the nutritional, textural, sensorial, and health-related properties of food products enriched with seaweeds and seaweed extracts. The effect of seaweed incorporation on properties of meat, fish, bakery, and other food products were highlighted in depth. Moreover, the positive effects of foods enriched with seaweeds and seaweed extracts on different lifestyle diseases such as obesity, dyslipidemia, hypertension, and diabetes were also discussed. The results of the studies demonstrated that the addition of seaweeds, in powder or extract form, can improve the nutritional and textural properties of food products. Additionally, low-fat products with less calories and less saturated fatty acids can be prepared using seaweeds. Moreover, the addition of seaweeds also affected the health properties of food products. The results of these studies demonstrated that the health value, shelf-life and overall quality of foods can be improved through the addition of either seaweeds or seaweed extracts.

A comprehensive approach to formulation of seaweed-enriched meat products: From technological development to assessment of healthy properties

Meat consumption is influenced by various kinds of factors, among them health implications. Different strategies can be effective in developing meat-based functional foods. These basically entail reducing the presence of compounds with negative health implications and enhancing the presence of beneficial compounds. This article reviews a comprehensive model for the development of meat-based functional foods based on a presentation of the research achieved in terms of the design and development of qualitatively and quantitatively modified meat products (frankfurters, patties and restructured steaks). These were reformulated to incorporate nutrients associated with three different seaweeds (wakame-Undaria pinnatifida; nori-Porphyra umbilicalis; and sea spaghetti-Himanthalia elongata) as sources of bioactive substances, while simultaneously reducing sodium and fat and improving fatty acid profiles. Those seaweeds were chosen, because in terms of composition and health implications, abundance on Spanish coasts, relatively widespread consumption, and suitability in terms of flavour and colour they are better suited than others for use as ingredients in new products. It also discusses the consequences of the use of this type of meat-based functional foods (combination of pork meat and 5% of each seaweed with or without hypercholesterolaemic agent included in the diets) on growing animals (Wistar male rats), and their effects on different aspects of lipoprotein metabolism, oxidative stress and liver structure. This article, then, reports a comprehensive approach to the production of seaweed-enriched meat products, considering aspects of technological development aimed at achieving the functional effect.

Seaweeds as Preventive Agents for Cardiovascular Diseases: From Nutrients to Functional Foods

Being naturally enriched in key nutrients and in various health-promoting compounds, seaweeds represent promising candidates for the design of functional foods. Soluble dietary fibers, peptides, phlorotannins, lipids and minerals are macroalgae's major compounds that can hold potential in high-value food products derived from macroalgae, including those directed to the cardiovascular-health promotion. This manuscript revises available reported data focusing the role of diet supplementation of macroalgae, or extracts enriched in bioactive compounds from macroalgae origin, in targeting modifiable markers of cardiovascular diseases (CVDs), like dyslipidemia, oxidative stress, vascular inflammation, hypertension, hypercoagulability and activation of the sympathetic and renin-angiotensin systems, among others. At last, the review also describes several products that have been formulated with the use of whole macroalgae or extracts, along with their claimed cardiovascular-associated benefits.

Silicon-Enriched Restructured Pork Affects the Lipoprotein Profile, VLDL Oxidation, and LDL Receptor Gene Expression in Aged Rats Fed an Atherogenic Diet

BACKGROUND

Research has shown that silicon can play an important role in protecting against degenerative diseases. Restructuring pork by partially disassembling meat permits the incorporation of active components with potential functional effects. However, there has been no research to date on the impact that silicon, as a functional ingredient in restructured pork (RP), has on lipoprotein composition, metabolism, and oxidation.

OBJECTIVE

This study was designed to evaluate the effect of silicon-enriched RP on lipemia, lipoprotein profile, and oxidation markers of aged rats fed high-fat, high-energy, cholesterol-enriched diets.

METHODS

RP samples similar to commercial sausages (16% protein and 22% fat, wt:wt) were prepared by mixing lean pork and lard alone or with silicon (1.3 g Si/kg fresh matter) under controlled conditions and then freeze-dried. Saturated fat-rich diets were designed by mixing 78.3% purified diet with 21.7% freeze-dried RP. Three groups composed of 8 aged male Wistar rats (1 y old) were fed for 8 wk a control RP (C) diet, a cholesterol-enriched RP (Chol-C) diet [C diet enriched with 1.26% cholesterol plus 0.25% cholic acid, or a cholesterol and silicon-enriched RP (Chol-Si) diet (same as the Chol-C diet but containing silicon)]. Plasma lipid concentrations, lipoprotein profile, the degree of VLDL oxidation, and LDL receptor gene (Ldlr) expression were tested.

RESULTS

Compared with the C diet, the Chol-C diet did not modify food intake or body weight but significantly increased (P < 0.05) plasma cholesterol (32%) and total lipids (19%), VLDL and intermediate density lipoprotein + LDL cholesterol (both >600%), total lipids and proteins (both >300%), and the degree of VLDL oxidation [conjugated dienes >250%; thiobarbituric acid-reactive substance (TBARS), 900%] and reduced Ldlr expression (64%) and liver arylesterase activity (54%). The Chol-Si diet partially normalized changes induced by the Chol-C diet. Compared with the Chol-C group, Chol-Si rats had lower VLDL compound concentrations (P < 0.001; e.g., 75% less VLDL cholesterol) and VLDL oxidation (65% less conjugated dienes and 85% less TBARS) but greater Ldlr expression (200%).

CONCLUSIONS

Silicon added to RP strongly counterbalanced the negative effect of high-cholesterol-ingestion, functioning as an active hypocholesterolemic, hypolipemic, and antioxidative dietary ingredient in aged rats.

Wakame (Undaria pinnatifida ) modulates hyperphosphatemia in a rat model of chronic renal failure

In chronic renal failure, inorganic phosphate (Pi) retention speeds up the progression to end-stage renal disease. The current therapy for hyperphosphatemia in patients with chronic renal failure consists of dietary Pi restriction combined with administration of Pi binders, but each therapy has practical problems. Thus, the discovery of foods or nutrients that inhibit Pi absorption may be useful for the treatment of hyperphosphatemia. In the present study, we investigated whether wakame (Undaria pinnatifida) is a useful food for the prevention of hyperphosphatemia in a rat model of renal failure. Feeding a diet containing 5% wakame significantly decreased plasma and urinary Pi levels and increased the amount of fecal Pi. In addition, wakame significantly reduced plasma blood urea nitrogen and plasma Pi levels in 5/6 nephrectomized rats fed a high-Pi diet. Biochemical analyses showed that the reduction of intestinal Pi absorption is the main reason for the decrease in plasma Pi levels in rats fed a diet containing wakame. In addition, feeding alginic acid and fucoidan, major components of wakame fiber, was effective in reducing plasma Pi levels in normal rats. Finally, we concluded that wakame may be a useful food for the prevention of hyperphosphatemia in rodents.

High-cholesterol diet enriched with onion affects endothelium-dependent relaxation and NADPH oxidase activity in mesenteric microvessels from Wistar rats

BACKGROUND

The aim of the present study was to examine the effects of onion as functional ingredient on the oxidative status, lipoprotein levels (total cholesterol-TC, HDL-C, LDL-C), triacylglycerides (TAG) and vascular reactivity of mesenteric arteries in hypercholesterolemic Wistar rats.

METHODS

Twenty-four animals were fed with three different diets [control, high-cholesterol diet (HC) and high-cholesterol enriched with onion diet (HCO)]. After seven weeks of experimental feeding the rats were euthanized for blood and tissues collection. TC, HDL-C, LDL-C and TAG were measured, and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(•+)) scavenging capacity and ferric reducing antioxidant power (FRAP) were determined in plasma. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities were assayed in erythrocyte lysates. Endothelium-dependent vasodilation to acetylcholine was evaluated in mesenteric arterial segments. NADPH oxidase (NOX) was also measured by lucigenin-derived chemiluminiscence.

RESULTS

The dietary cholesterol content significantly affected plasma lipoprotein levels, increased superoxide generation from NOX, and caused impaired endothelium-dependent vasodilation in the rat mesenteric arteries. Onion ingredient improved antioxidant status in HCO group, as it was evidenced by ABTS(•+) and FRAP values and SOD and GPx enzyme activities compared to the HC-fed group, reduced the increment in NOX activity and reversed endothelial dysfunction promoted by the HC diet. Scavenging of superoxide with TEMPOL or inhibition of NOX with apocynin improved endothelium-dependent vasodilation only in HC-fed rats.

CONCLUSIONS

Enrichment of diet with onion as functional ingredient could be proposed as a complementary approach to prevent or partially modulate vascular dysfunction, reducing some of the risk indexes linked to initial development of atherosclerosis.

Protective effects of sea spaghetti-enriched restructured pork against dietary cholesterol: effects on arylesterase and lipoprotein profile and composition of growing rats

There is a general assumption that seaweeds are hypocholesterolemics and antioxidants. However, controversial results suggest specific properties for each individual alga. This study aims to assess the effect of including Sea Spaghetti alga (S) in a restructured-pork (RP) diet, both enriched and not enriched with dietary cholesterol, on arylesterase (AE) activity and lipoprotein concentration and composition of Wistar rats. Four groups of 10 growing male Wistar rats were each fed a mix of 85% AIN-93M diet and 15% freeze-dried RP for 5 weeks. The control group (C) consumed control RP-C; the S group consumed RP-S with 5% seaweeds; the Chol-C group consumed the C diet but enriched with cholesterol (2.43%) and cholic acid (0.49%); the Chol-S group consumed the S diet but enriched with cholesterol and cholic acid. AE activity was five times higher (P<.01) in S compared with C rats, but three times lower in Chol-S compared with Chol-C rats (P<.01). The Chol-C diet induced hypercholesterolemia but reduced triglycerides (TG), giving rise to the presence of very low-density lipoprotein (VLDL) that was enriched in cholesterol. The Chol-S diet partially blocked (P<.001) the hypercholesterolemic induction of the Chol-C diet, and reduced TG levels (P<.05) with respect to S rats. The cholesterol supplementation increased total cholesterol, VLDL-cholesterol, and intermediate-density lipoprotein+LDL-cholesterol (IDL+LDL)-cholesterol (P<.001) in Chol-C rats, but the effect was lower in the Chol-S diet. In conclusion, RP-S increases the antioxidant capacity within a noncholesterol enriched diet while improving the lipoprotein profile within a cholesterol-enriched diet.

Effects of seaweed-restructured pork diets enriched or not with cholesterol on rat cholesterolaemia and liver damage

Seaweed enriched-restructured pork (RP) is a potential functional food. However, indications of adverse effects associated with herbal medications, which include among others liver failure, toxic hepatitis, and death have been reported. Cholesterol feeding produces hepatomegalia and fat liver infiltration. The effect of seaweed-RP diet, cholesterol-enriched or not, on plasma cholesterol, liver damage markers, structure, and cytochrome CYP4A-1 were evaluated after 5 wk. Eight rat groups were fed a mix of 85% AIN-93M rodent-diet plus 15% RP. The Cholesterol-control (CC), Cholesterol-Wakame (CW), Cholesterol-Nori (CN) and Cholesterol-Sea Spaghetti (CS) groups respectively consumed similar diets to control (C), Wakame (W), Nori (N), and Sea Spaghetti (S) but as part of hypercholesterolaemic diets. CN and CS significantly blocked the hypercholesterolaemic effect observed in CC group. After 5-wk, N and S diets increased the CYP4A-1 expression. However, seaweed-RPs were unable to reduce the histological liver alterations observed in CC group. Larger and more abundant hepatocellular alterations were found in CS and CN rats suggesting that the hypocholesterolaemic effects of these seaweed-RPs seem to be a two-edged sword as they increased liver damage. Future studies are needed to understand the involved mechanisms.

Development and assessment of healthy properties of meat and meat products designed as functional foods

This review deals with the two major aspects to be considered in the context of meat-based functional foods and human health. One involves the different strategies used to improve (increase or reduce) the presence of bioactive (healthy and unhealthy) compounds in meat and meat products in order to develop potential meat-based functional foods; these strategies are basically concerned with animal production practices, meat processing and storage, distribution and consumption conditions. Since the link between the consumption of those foods and their potentially beneficial effects (improving health and/or reducing the risk of several chronic diseases) needs to be demonstrated scientifically, the second aspect considered is related to intervention studies to examine the functional capacity of meat-based potentially functional foods in humans, discussing how the functionality of a food can be assessed in terms of its effects on health in relation to both target body functions and risk factors.

Association of lipids with oxidative stress biomarkers in subclinical hypothyroidism

Objective. The aim of the present study was to evaluate the oxidative stress biomarkers in patients with subclinical hypothyroidism (n = 20) and health controls (n = 20). Subjects and Methods. Total cholesterol (TC), triglycerides (TGs), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), thiobarbituric acid reactive substances (TBARSs), catalase (CAT), superoxide dismutase (SOD), and arylesterase (ARE) were analyzed. Results. TC, LDL-C, TBARS, and CAT were higher in subclinical hypothyroidism patients, whereas SOD did not change. Arylesterase activity was significantly lower in the SH group, compared with the control group. Correlation analyses revealed the association of lipids (TC and LDL-C) with both oxidative stress biomarkers and thyrotropin (TSH). Thyroid hormones were correlated only with triglyceride levels. In addition, TSH was significantly correlated with TBARS, CAT, and SOD. However, no significant correlations were observed after controlling TC levels. Conclusions. We found that SH patients are under increased oxidative stress manifested by reduced ARE activity and elevated lipoperoxidation and CAT activity. Secondary hypercholesterolemia to thyroid dysfunction and not hypothyroidism per se appears to be associated with oxidative stress in subclinical hypothyroidism.