Role of histaminergic system in the regulation of nutrition
In the review modern data on a role of various humoral factors (neuromediators, hormones, adipocytokines etc.) in regulation of appetite, food consumption and obesity are presented. The special attention is paid to the role of histamine and histamine receptors of H3-type in processes of regulation of a food intake. Interaction of various humoral factors is discussed at obesity and other alimentary-dependent diseases.
Vitamins and oxidative stress
The central and local stress limiting systems, including the antioxidant defense system involved in defending the organism at the cellular and systemic levels from excess activation response to stress influence, leading to damaging effects. The development of stress, regardless of its nature [cold, increased physical activity, aging, the development of many pathologies (cardiovascular, neurodegenerative diseases, diseases of the gastrointestinal tract, ischemia, the effects of burns), immobilization, hypobaric hypoxia, hyperoxia, radiation effects etc.] leads to a deterioration of the vitamin status (vitamins E, A, C). Damaging effect on the antioxidant defense system is more pronounced compared to the stress response in animals with an isolated deficiency of vitamins C, A, E, B1 or B6 and the combined vitamins deficiency in the diet. Addition missing vitamin or vitamins restores the performance of antioxidant system. Thus, the role of vitamins in adaptation to stressors is evident. However, vitamins C, E and beta-carotene in high doses, significantly higher than the physiological needs of the organism, may be not only antioxidants, but may have also prooxidant properties. Perhaps this explains the lack of positive effects of antioxidant vitamins used in extreme doses for a long time described in some publications. There is no doubt that to justify the current optimal doses of antioxidant vitamins and other dietary antioxidants specially-designed studies, including biochemical testing of initial vitamin and antioxidant status of the organism, as well as monitoring their change over time are required.
Analysis of regulatory basis for organization of clinical nutrition in medical institutions of the Russian Federation
The article analyzes regulatory basis for organization of clinical nutrition in medical institutions of Russia. It is shown that the strategy of therapeutic measures in acute and chronic diseases a central place to take dietary therapy with adequate provision of energy and plastic body’s needs, correction of metabolic disorders and risk factors for comorbidity. Prior to the confirmation of the order of Ministry of Health of Russia from 05.08.2003, № 330 «On measures to improve nutritional care in health care institutions in the Russian Federation» clinical nutrition in medical institutions was based on the nosological principle, in the form of daily diet – a diet designed for each concrete Diseases which are identified by a number from 1 to 15. According to the order of Ministry of Health of Russia from 05.08.2003, № 330 in the health care practice has introduced a new range of diets (system standard diets), which is based on the principle of adapting the chemical composition and energy value of the diet to the individual clinical and pathogenic features of the disease and combines previously used diet numbering system. It is shown that the organization of clinical nutrition should be based on common requirements imposed on the federal level and at the level of the subject of the Russian Federation. In order to optimize clinical nutrition is necessary to determine the methodological approaches to personalization through the introduction of diet in health care practice of modern innovative technologies health food, performing preventive and treatment of the problem (implementation of Article 39 of the Federal Law of 21.11.2011 № 323-FZ «On the basis of health protection in the Russian Federation», the Order of the Government of the Russian Federation of 25.10.2010 № 1873-r «On the basis of the state policy in the field of nutrition to 2020 year»).
Clinical assessment of dietary correction of metabolic syndrome by using specialized food product enriched with chrome
Effectiveness of Laminaria jam enriched with chromium has been investigated in ambulatory patients with metabolic syndrome. 50 patients ranging in age from 30 to 65 years (mean age 53,4±7,5) were under observation during 6 months. 30 patients from comparison group were given recommendations on modeling of lifestyle (diet, reduced and controlled dosed physical loading) and they received medical treatment. Main group of patients (20 people) in addition received dietary product – Laminaria jam, enriched with chromium, which daily dose (20 g) contain 280 μg of iodine and 66 μg of chromium. In both groups declines of overweight, improving clinical and laboratory parameters, adaptive organism reserves and quality of life has been registered. Patients from the main group referred good organoleptic properties of dietary product, it was well tolerated by patients without causing unwanted side effects. After 6 months of a dietary correction mean relative body mass reduction in the main group amounted to 5,0% while in the comparison group – 3,0%. Positive dynamics of the circumference of the waist in patients accounted for 5,9% in main group and 3,1% in comparison group. Systolic and diastolic blood pressure decreased in the main group, an average of 20,5 and 24,2%; in the comparison group – 10,5 and 13,3% respectively. The average reduction in LDL-C reached 28,3% in the main group and 18,3% in the comparison group. Triglyceride levels decrease was an average of 18,9% in the studied group, that was significantly higher than in the control group (3,7%). The dynamics of OGTT in main group amounted to 13,1% while in the comparison group – 8,6%. Differences between group indices were statistically significant for most of the variables. The inclusion of the dietary product in a range of therapeutic and preventive activities under metabolic syndrome has been shown to improve clinical and metabolic indicators (body mass, arterial pressure, lipid and carbohydrate metabolism parameters) compared with standard therapy.
IMMUNOLOGY AND BIOCHEMISTRY OF NUTRITION
The influence of dietary fibers on cell immunity under the adequate nutrition and in the presence of alimentary polyhypovitaminosis in rats
The effect of wheat bran on cell immunity in rats adequately provided with vitamins or insufficiently supplied with vitamins has been investigated. 48 male Wistar rats (58,1±0,5 g) were divided into 6 group and fed with complete semi-synthetic diet, containing 100% or 20% of vitamin mixture (Vit) with or without supplement of insoluble dietary fiber (DF) in the dose corresponding to the upper allowable level of its consumption (5% wheat bran of diet mass) for 4 weeks. The animals of the 1 group received 100% of vitamin mixture (100% Vit); 2 group – 100% Vit+DF; 3 group – 20% of vitamin mixture (20% Vit); 4 group – 20% of vitamin mixture and DF (20% Vit+DF). The next 5 days rats from vitamin-deficient groups were fed with diets supplemented with 80% of Vit: (5 group – 20% Vit+ 80% Vit; 6 group – 20% Vit+DF+80% Vit). The contents of lymphocytes, relative quantity of B- (CD45RA+) and T-lymphocytes (CD3+), subpopulations of T-lymphocytes: T-helper (CD3+CD4+) and cytotoxic T-lymphocytes (CD3+CD8+), NK-cells (CD161a+) in the peripheral blood of rats were determined by the method of flow cytometry using Beckman Coulter FC 500 (USA) cytometer. In rats fed complete semi-synthetic diet supplemented with DF (100% Vit+DF) the reduction of relative contents of T-lymphocytes and the increase of the fraction of cytotoxic T-lymphocytes in peripheral blood has been found. The analogous changes and more pronounced degree of immunosupression, that appeared in a lymphocytopenia, much smaller level of T-lymphocytes, T-helper and increase of cytotoxic T-lymphocytes content in rats fed a low vitamins diet (20% Vit) in comparison with these parameters of control group, have been detected. In rats received 20% Vit+DF the suppressed cell immunity was accompanied with decreased level of NK-cells. Normalization of vitamins content in the diets of rat deficient groups led to an almost complete recovery of cell immunity indicators to the level of the animals from the corresponding control groups. Inclusion in the diet of fiber requires its further enrichment with vitamins. Special studies of fiber diet influence on are needed to clarify the upper allowable level of insoluble dietary fiber in human nutrition.
Vitamin C in fruits and vegetables
Strong opinion about reducing vitamin C content in traditional cultivars of fruits and vegetables as a result of intensive farming practices, on the one hand, and depletion of soil, waste of fertilizers, on the other hand, takes place. The aim of the study was to assess changes in vitamin C content in fresh vegetables, fruits and berries from the 40s of last century to the present. Available national and foreign data from official tables of the chemical composition tables published in different years, including the most typical values, based on the results conducted in a number of research institutes, laboratories and university departments, as well as some original investigations and unpublished own results were used to analyze possible changes of vitamin C content in fruits and vegetables. For comparison we take into consideration only results from the most common and affordable since the last century method of visual titration, which has a relative error of 20%. Analysis of vitamin C content conducted according 5–58 studies from the 40s of the last century to the present, for 32 types of greens and vegetables (potatoes, various types of cabbage and onion, garlic, carrot, turnip, tomato, pepper, eggplant, cucumber, squash, peas, turnip, garden radish, parsnip, rhubarb, parsley, dill, lettuce, onion, spinach, sorrel), and according to 6–50 studies of 24 sorts of fruits (apple, pear, mandarin, orange, lemon, grapefruit, pineapple, banana, watermelon, cantaloupe, grapes, peach, apricot, plum, cherry, blackberry, blueberry, strawberry, raspberry, blackberry, gooseberry, black currant, red and white) has been done. It was found that the average content of vitamin varies slightly. Deviations from the average for all the years of research do not exceed the standard deviation. Analysis of longitudinal data did not confirm a vitamin C decrease. This means that vitamin value C of fruits and vegetables remains approximately constant, due to the successful selection of new varieties with increased vitamin value. Thus, the view of reducing the C-vitamin value in cultivars produce proved unfounded.
Analytical methods for control of foodstuffs made from bioengineered plants
Foodstuffs made by modern biotechnology are requiring for special control. Analytical methods used for these purposes are being constantly perfected. When choosing a strategy for the analysis, several factors have to be assessed: specificity, sensitivity, practically of the method and time efficiency. To date, the GMO testing methods are mainly based on the inserted DNA sequences and newly produced proteins in GMOs. Protein detection methods are based mainly on ELISA. The specific detection of a novel protein synthesized by gene introduced during transformation constitutes an alternative approach for the identification of GMO. The genetic modification is not always specifically directed at the production of a novel protein and does not always result in protein expression levels sufficient for detection purposes. In addition, some proteins may be expressed only in specific parts of the plant or expressed at different levels in distinct parts of plant. As DNA is a rather stable molecule relative to proteins, it is preferred target for any kind of sample. These methods are more sensitive and specific than protein detection methods. PCR-based test can be categorized into several levels of specificity. The least specific methods are commonly called «screening methods» and relate to target DNA elements, such as promoters and terminators that are present in many different GMOs. For routine screening purpose regulatory elements 35S promoter, derived from the Cauliflower Mosaic Virus and the NOS terminator, derived from the nopaline synthase gene of Agrobacterium tumefaciens, are used as target sequences. The second level is «gene-specific methods». These methods target a part of the DNA harbouring the active gene associated with the specific genetic modification. The highest specificity is seen when the target is the unique junction found at the integration locus between the inserted DNA and the recipient genome. These are called «event-specific methods». For a quantitative assessment of GMO the most promising is PCR with the detection of results on the real time-scale. This method has several advantages such as high sensitivity and specificity, little time of analyses, which are conducted in a closed test-tube without contamination environment of PCR products. The microarray technologies have been developed in the past few years. The main principle of the micro-array technology is miniaturization. Methods can be performed on a much larger scale in much smaller volumes.
Rapid determination of food grain infection by fungi Fusarium and their species detection (part 1)
Currently contamination of food grains with Fusarium spp. is determined by conventional mycological methods and can last up to 30–40 days. The method specificity is highly dependent on the subjective evaluation of the researchers. The alternative to traditional mycological methods is detection by PCR. The purpose of the study was to improve the contamination analysis method of food grains infected by Fusarium for analysis time reducing and species detection specificity increasing. Investigations were carried out on food grains samples harvested in 2009–2011 from 5 federal regions of Russia. On the first stage, 100 grains were sowing on potato-sucrose medium and then incubated at 24 °C for 7–10 days. At the second stage, the Fusarium species composition grown from food grains was estimated by two methods. The first method was mycological for monospore isolates. The second one was PCR analysis of DNA extracts from the combined sample of Fusarium mycelium which grew on a foodgrains sample. Species-specific primers of such mycotoxins producers as F. graminearum, F. culmorum, F. sporotrchiodes, F. langsethiae, F. poae, F. avenaceum, F. tricinctum were used for PCR detection. The species composition of viable Fusarium spp. fungi revealed in foodgrains samples by mycological method completely concided with the results of PCR analysis. In result, the method that combines traditional mycological sowing for detection of viable species with PCR species detection of the mycelium in integrated sample has been developed. The method significantly reduces test duration (3–4 times) by excluding the sieving step in obtaining monospore fungi isolates for further species identification. The method also allows obtaining reliable data on the viable Fusarium speсies including producers of toxins in foodgrains. Thus, the idea of improving of the identification stage allowing reducing labor costs and increasing of the method specificity was realized.
Determination of chondroitin sulfate in food supplements by capillary zone electrophoresis
Chondroitin sulfate is widely used as an ingredient in food supplements. A method of capillary zone electrophoresis for qualitative and quantitative analysis of chondroitin sulfate in food supplements has been developed. The system of capillary electrophoresis Agilent 3D CE (USA) with diode array detector (spectral range 190–400 nm, 192 nm was used to quantity), quartz capillary Agilent with effective length 56 cm (USA) (internal diameter 50 μm, temperature 25 °C, 30 kV, negative polarity) and 50 mM phosphate buffer (рН 3,5) has been used. Quantity limit of this method was 0,5 g/kg. It was used for determination of content of chondroitin sulfate in 14 food supplements. The chondroitin sulfate was detected in all test samples with deviation from the declared content (25–600 mg per capsule or tablet) at the level of 1 to 9%. The applicability of the elaborated method for assessing of food supplements quality has been shown.
Hygiene of nutrition
Determination of authenticity and thermal transformation of bee products by NMR spectroscopy
NMR studies of carbohydrate composition of several varieties of honey and surface layer of Altai honey were carried out. Investigated samples were differing by their geobotanical nature, year of collection and thermal effect to which they were subjected. It is shown that compared with honey its surface layer is enriched with glucose while fructose is depleted. It is established that fructose diastereoisomers in honey are in equilibrium concentrations, so their distribution does not change at heating. The effect of temperature on the ratio of α-/β-form glucose in honey was established. It has been shown that in the unheated honey the value of the ratio α-/β- glucose was >1, when honey was heating glucose anomerization occured and due to this the ratio value became <1. Therefore, the ratio of glucose anomers in honey can be considered as an index of its thermal transformation and can be used as an additional technique at examining the honey quality.
Comparative characteristics of antioxidant capacity and energy content of some foods
The paper presents a comparative evaluation of antioxidant capacity and energy values of different foods groups in order to identify the most efficient combinations for correction of metabolic disorders associated with an imbalance in antioxidant system. In study integral method for determining of antioxidant and energy indicators (patent № 2 455 703) has been used. It has been revealed that the highest antioxidant-energy capacity (AE) of fresh juices has a pomegranate juice (AE=3895,9±241,4 mg/L·kJ–1), other fresh juices inferior to him on this indicator: grenade>orange>lemon=apple>pomelо>mandarin>persimmon>kiwi>pears>avocado. Among dairy products the highest AE belongs to boiled fermented milk – «ryazhenka» (AE=40,9±2,7 mg/L·kJ–1), other dairy products can be placed in line with index AE: ryazhenka=>kefir>yogurt. Most of fresh juices were significantly superior to antioxidant-energy potential of other foods. Despite the fact that dairy products AE were lower than AE of some juices, they were much superior to AE values of fast food products (biscuits, potato chips, popcorn). This demonstrates need to reduce the quota of fast foods in the diet to prevent the risk of reduction potential of the endogenous antioxidant system.