Current Nutrition & Food Science - Volume 5, Issue 1, 2009

Metabolic syndrome places patients at high risk to many other health problems, as their bodies are in a perpetual state pro-inflammation and pro-thrombosis. In many cases, a regulated diet and increased exercise is sufficient in rectifying their condition, however for many patients, drug intervention is necessary. In recent years, calorie restriction has been shown to improve the health of patients afflicted with aging-related diseases, specifically those associated with metabolic syndrome, and researchers are now exploring drugs that mimic calorie restriction. Resveratrol mimics a calorie restricted diet as it has been shown to attenuate health benefits, including anti-platelet aggregation, vasorelaxation, atherosclerosis suppression, and lipid metabolism similar to a calorie restricted diet. Additionally, it modulates many of the pathways associated with metabolic syndrome, leading researchers to believe it has potential as a burgeoning therapeutic approach.

The physiopathological decline in appetite and food intake known as “anorexia of aging” can lead to involuntary weight loss and protein-energy malnutrition, with devastating consequences in older men and women. Food intake can be influenced by numerous endogenous and exogenous factors, both physiological and pathological: mechanisms underlying age-related anorexia are multifactorial, and not completely understood. Early recognition of anorexia, nutritional and pharmacological interventions can help prevent the development of malnutrition and poor clinical outcome in the elderly.

Anorexia nervosa is a challenging disorder to treat, both from a medical and a psychiatric standpoint. Part of the clinical difficulty is based on the patient's ardent desire to resist meaningful weight restoration, and the debilitating fear of food which defines this disorder. However, there are also a litany of medical complications which can interfere with the refeeding process and which affect many different body systems. One particularly concerning sequela of this refeeding is known as the refeeding syndrome. This potentially fatal syndrome most commonly occurs with aggressive refeeding programs that do not incorporate close surveillance for the signs and symptoms of the newly acquired anabolic condition. Without early detection and intervention, progressive cardiopulmonary failure can occur. Cautious and restrained provision of calories together with vigilant oversight and checking of electrolytes on a frequent basis will prevent this sobering syndrome. The biochemical, cardiac, and gastrointestinal systems are most prominently affected during early periods of weight restoration. However, weight restoration remains the key to a successful treatment outcome in patients with anorexia nervosa, and thus, familiarity with these issues is imperative for the caregivers of anorectic patients.

The isoelectric behavior of food proteins has been well characterized in the food science literature. The isoelectric point (pI) of a protein is a pH at which the protein maintains a zero net electrostatic charge. In this state, protein-protein hydrophobic interactions overcome protein-water electrostatic interactions and the minimum solubility of proteins results. Consequently, several food science laboratories have begun active research on the application of the pI to recover functional muscle proteins, particularly fish myofibrillar proteins. Fish stocks are declining and several fisheries are currently over-exploited and may collapse by mid century. Fish processing by-products are considerable and include heads, frames, viscera, and etc. By-products are land-filled, ground-and-discarded or otherwise diverted from human consumption. By-products retain ample muscle proteins and oil. The oil contains omega-3 fatty acids. Due to the lack of commercially available technology to recover proteins and lipids from fish processing by-products or underutilized aquatic species, this tremendous resource is currently unavailable for human consumption. Fish proteins and oil from otherwise low-value by-products can be recovered using isoelectric solubilization/precipitation with recovery yields of approximately 90%. Recovered proteins and oil retain functionality and nutritional value for human food products. This article reviews the fundamental biochemical principles of food proteins and lipids as well as their structure and interaction with water in relation to the isoelectric behavior. Additionally, the most recent developments regarding application of isoelectric solubilization/precipitation to recover functional and nutritious proteins and oil from fish processing byproducts and underutilized aquatic species are addressed.

It is not clear whether animals require exogenous carnitine, and over the past 20 years, the scientific discussion regarding this subject continued with arguments pro and contra. Some studies observed that feeding fish with dietary carnitine supplements may improve growth and protect against several disease outbreak. However, such growth improvement was not always observed. The results can be interpreted in two ways: Firstly, the endogenous carnitine biosynthesis may be adequate to maintain sufficient tissue levels during growth. Secondly, the responses to dietary carnitine supplements are influenced by environmental and physiological interactions. The aim of this mini review was to provide an overview of the positive effects of dietary carnitine supplementation on fish metabolism, and possible factors that might alter dietary carnitine requirements, such as feed composition, species, age, tissue dependence on fatty acid oxidation and metabolic conditions.

A great part of the population is under pharmacological treatment or takes herbal or other kinds of supplements. The influences between drugs and food/diet are of increasing interest for different reasons: - The increasing importance and detection of food-drug interactions; - The importance of an integrated dietetic-pharmacological treatment in diseases as diabetes mellitus, hypertension, hyperlipidaemia, etc; - The use of drugs and supplements in obesity; - The influence of diet in improving the nutritional status and reduction of drug adverse reactions in cancer and AIDS treatments. Therefore, dieticians need to have a broad knowledge of pharmacology, especially in the areas described before. In the dietician curriculum of the students of our school we have integrated applied pharmacology. We have worked in order to orient and adapt our pharmacology program to these specific subjects. This will provide the dietician with skills in order to obtain the optimum outcome in the treatment of their patients, working in a multidisciplinary team (nurses, physicians, pharmacists, physiotherapists, etc.).

Vitamin C (L-ascorbate) is a good antioxidant. Because of its water soluble nature it can work both inside and outside the cells to combat free radical damage. It has several applications starting from application in cancer therapeutics to treatment of common cold. Human, primates and guinea pigs can not synthesize this nutrient and must have to take this nutrient with diet. The current review brings together information available about the applications of Vitamin C with emphasis on antioxidant property and application in cancer therapy. The contradicting reports about application of Vitamin C in cancer therapy are also discussed.

The study of the mechanisms involved in cell damage mediated by oxidative compounds as well as the evaluation of biomarkers of the cellular antioxidant defence system in such conditions could help to prevent appearance and development of oxidative stress related diseases. The present overview describes a model of oxidative stress in cultured cells based on the evaluation of cellular antioxidant defences and suitable to assay the possible chemopreventive effect of dietary compounds. Since the liver is the major place for xenobiotic metabolism, research on chemopreventive compounds should focus on the response of liver cells. Human HepG2, a well differentiated transformed cell line from hepatic origin, is a reliable model widely used for biochemical and nutritional studies where many compounds and conditions can be assayed with minor inter-assay variations. The products selected for this overview are representative of different constituents included in the human diet and possess diverse structures and mechanisms of antioxidant activity: phenolic compounds such as quercetin and hydroxytyrosol, a Maillard reaction product such as coffee melanoidin and an oligoelement such as a selenium derivative. The results confirm the reliability of the model and give more insight into the specific mechanisms involved in the biological activity of the tested compounds.

In this study, efforts were focused on the dose-responses of the operating parameters (i.e. different processing methods (extruded/non-extruded), additives (tomato powder, buckwheat powder and rice powder), and extracts concentrations (0, 3, 6, 12, 30, 60 (mg/mL))) on the hydrogen peroxide scavenging, superoxide anion scavenging and reducing power of methanol extracts of the extrudates. The experiment is a 2 x 3 x 6 factorial design. Samples of each treatment were collected and the hydrogen peroxide scavenging, superoxide anion scavenging and reducing powers were measured and analyzed, using the one-way variance analyses (ANOVA) of the SPSS 9.0 software package. Experimental results indicated that: (a) The extrudates with tomato powders had the highest hydrogen peroxide scavenging ability, extrudates with buckwheat powders had lower, and the extrudates with the rice powders had the lowest ability. However, the antioxidative ability of the extrudates with buckwheat powders and rice powders decreased with increasing reaction time, except the extrudates with tomato powder (b) The extrudates with tomato powders and rice powders had the best superoxide anion scavenging ability, however, the extrudates with buckwheat powders had the lowest (c) The extrudates with tomato powders had the highest reducing powder ability, followed by the extrudates with buckwheat powders, whereas the extrudates with the rice powders had the lowest ability (d) The extrudates with tomato powders had a better antioxidative abilities than the others additives and (e) There was no significant difference between the hydrogen peroxide scavenging ability and the reducing power ability by different processing methods, except the products after extrusion had a better and significant superoxide anion scavenging ability.

Background: Transthyretin has been widely used as a biomarker for identifying protein-energy malnutrition (PEM) and for monitoring the improvement of nutritional status after implementing a nutritional intervention by enteral feeding or by parenteral infusion. This has occurred because transthyretin (TTR) has a rapid removal from the circulation in 48 hours and it is readily measured by immunometric assay. Nevertheless, concerns have been raised about the use of TTR in the ICU setting, which prompts a review of the actual benefit of using this test in a number of settings. TTR is easily followed in the underweight and the high risk populations in an ambulatory setting, which has a significant background risk of chronic diseases. It is sensitive to the systemic inflammatory response syndrome (SIRS), and needs to be understood in the context of acute illness to be used effectively. There are a number of physiologic changes associated with SIRS and the injury/repair process that will affect TTR and will be put in context in this review. The most important point is that in the context of an ICU setting, the contribution of TTR is significant in a complex milieu.