Problems of Nutrition

The prevalence of small intestinal bacterial overgrowth (SIBO) is increasing worldwide, especially in countries with high rates of urbanization. The growth of pathogenic and/or opportunistic bacteria in the small intestine can cause clinical symptoms and digestive and absorption disorders.

The aim of the review was to analyze available literature on SIBO in various gastrointestinal pathologies.

Material and methods. A literature search was conducted for the last 10 years using the library platforms PubMed, Medscape by keywords: “small intestinal bacterial overgrowth”, “SIBO”. A total of 1112 scientific papers were found, of which 124 English-language and 28 Russian-language publications were subject to analysis. Of these, 41 articles (including 5 Russian-language ones) corresponding to the topic of this review were included in the review.

Results. The article presents data reflecting the pathophysiology and factors contributing to the development of SIBO. It is shown that irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) and a number of organic and functional diseases of the gastrointestinal tract (GIT) are closely associated with SIBO. The features of the pathogenesis of SIBO in gastrointestinal diseases (IBS, IBD, functional dyspepsia, celiac disease, non-alcoholic steatohepatitis, chronic pancreatitis, etc.) and its influence on the course of gastrointestinal pathology are described.

Conclusion. It is impossible to unambiguously assess the influence that SIBO and various types of gastrointestinal pathology have on each other, since, on the one hand, SIBO can develop as a result of gastrointestinal diseases, and on the other hand, it can serve a predictor of the deterioration of these diseases. Most likely, we are talking about the emergence of a vicious circle, to break which it is necessary to eradicate the microorganisms that cause SIBO. This can be achieved both through drug treatment and by adjusting the diet of patients. An important element of non-specific prevention of SIBO is also timely rational treatment of gastrointestinal diseases that contribute to the development of this syndrome.

In order to navigate the research results when determining the somatotype profile, it is necessary to know certain patterns that the somatotype undergoes during growth and development, as well as the features of body type formation depending on gender, age, race and the level of physical activity.

The purpose of the research was to identify the main patterns of somatotype formation and dynamics during ontogenesis depending on gender, age, race, the level and nature of physical activity.

Material and methods. 40 literature sources were analyzed, searches by keywords “Heath–Carter scheme”, “Sheldon scheme”, “somatotype”, “sports somatotyping”, “children’s somatotyping” were performed in the PubMed, Scopus, Web of Science Elsevier, eLibrary databases.

Results. There are no differences in the distribution of somatotypes between boys and girls aged 1–4 years. After 5 years, the somatotype profile of boys shifts towards a higher mesomorph score, and the somatotype profile of girls – towards higher endomorph and ectomorph scores, which reflects a typical adolescent restructuring, expressed in masculinity of boys and endomorph changes of girls. This divergence of somatotypes continues until the age of 18. Further, in the subgroups of adult men and women, the somatotype undergoes the same changes regardless of gender, expressed by an increase in the score values of the endomorph and mesomorph components up to the age of 60. The differences in the somatotype profile depending on ethnicity and place of residence (rural or urban residents) are associated with different physical activity, eating habits, diet and genetic hereditary factors. The score values of the somatotype components in athletes differ from those in persons with sedentary lifestyle, and athletes of various sports specializations differ from each other in somatotype profile.

Conclusion. Along with the assessment of morphological parameters and body composition, somatotyping is one of the methods for a comprehensive assessment of the level of physical development, expanding the understanding of the ratio of muscle and fat components of body mass. The existing data on the prevalence of various somatotypes in the a conditionally healthy population are indicative for a comparative assessment of newly examined individuals, since on the one hand the somatotyping results depend to a certain extent on the method of obtaining data; and on the other hand the somatotype profile changes during ontogenesis, and is influenced by gender, age, ethnicity, as well as the level of physical activity and even sports specialization.

The ability to digest lactose in adulthood is caused by a genetic mutation that emerged following the domestication of cattle approximately 10 000 years ago. However, many adults retain primary lactase deficiency – the ancestral phenotype characterized by a decline in lactase enzyme activity after weaning. While the global prevalence of this condition is well-documented, reliable large-scale population data for Russia have been lacking so far. Microarray genotyping of genetic markers now enables high-quality, up-to-date research covering representative samples from diverse ethnic groups across Russia’s regions.

The purpose of the research was to compare the frequency of GG genotype in rs4988235 (13910 C/T) in the regulatory region (MCM6) of the lactase enzyme gene LCT, which determines the genetic risk of lactase insufficiency manifestation, in populations living in Russia and evaluate the differences between Russian regions.

Methods. The largest multi-ethnic genetic study on lactase deficiency in Russia was conducted on a sample of 24,439 individuals in 56 populations. The percentage of an individual belonging to each ethnic group was estimated by calculating the ancestral contribution to an individual’s genetic makeup. In addition, we calculated the frequency of the rs4988235 GG genotype in regions of Russia using information on the individual’s current location and place of birth.

Results. The prevalence of lactase deficiency by GG genotype rs4988235 in the Russian population was 45.2 and 42.8% (95% confidence interval 42.1–43.4) in the East Slavs group. The study revealed a significant variability (22.8–83.2%) in the regional prevalence of lactase deficiency by GG rs4988235 genotype. The dependence of the regional prevalence of lactase deficiency on the current place of residence is supported by the geographical features of the Russian territory and the history of pastoralism in different regions.

Conclusion. The findings may be useful for developing regional nutrition recommendations and optimising the Russian market for lactose-free and low-lactose products, and justify the importance of genetic testing for diagnosis, highlighting the interdisciplinary relevance of the study.

β-Cryptoxanthin, along with β-carotene and α-carotene, is a precursor to vitamin A, which plays an important physiological role in the body. β-Cryptoxanthin is found in significant amounts in a limited number of dietary sources. The highest levels of β-cryptoxanthin are found in yellow, orange and red vegetables and fruit (persimmons, papaya, sweet peppers, tangerines, corn, peaches, oranges, etc.).

The aim of this study was to perform a hygienic assessment of β-cryptoxanthin intake levels, identify its main food sources in young adults in the summer-autumn period.

Material and methods. An online questionnaire was developed to establish β-cryptoxanthin intake levels from dietary sources. The questionnaire contained a list of products containing β-cryptoxanthin and common in the Russian food market. Respondents indicated the portion of food consumed the day before the survey. Data collection was carried during the period from June to October 2023. The study involved 214 respondents (173 women and 41 men) aged 18–35 years (mean age 23.4±5.2 years).

Results. The average β-cryptoxanthin intake was 0.58±0.63 (Me=0.21 [0.03; 0.66]) mg/ day. At the same time, only 15.4% of respondents had an intake more than 1.0 mg/day, which was ensured both by a variety of food sources in the diet (from 3 to 6 items) and by inclusion individual products with high content of β-cryptoxanthin. The preferred sources of β-cryptoxanthin for the majority of respondents in groups with high dietary levels (more than 1.5 mg/day) were sweet red peppers, peaches, watermelon, tangerines and orange juice. In groups with low and minimal levels of β-cryptoxanthin (less than 1.0 mg/day), along with the indicated products, its intake was due to the consumption of red pepper and paprika spices, dried cilantro, yellow and green sweet peppers, hot pepper sauce, canned jalapeno peppers, corn, oranges, apricots, nectarines, plums, peach and watermelon juices, canned peaches, dried papaya, potato chips. Despite the diversity of dietary sources, low and minimal levels of β-cryptoxanthin intake were due to both insufficient intake and selection of foods with low β-cryptoxanthin content per serving.

Conclusion. In 15.4% of respondents, the daily intake of β-cryptoxanthin was more than 1.0 mg/day, in 65.4% of respondents it was less than 1.0 mg/day, and in 19.2% of participants there were no sources of β-cryptoxanthin in the diet. More often than others, sweet red pepper, orange juice, and paprika and red pepper spices were present in the diet of respondents, regardless of the level of β-cryptoxanthin intake, but their contribution to the intake of β-cryptoxanthin was determined by the volume of a single serving, and therefore spices cannot be considered priority sources.

The quest for new bioactive compounds with an immune-oriented focus, as well as the study of the mechanisms of immunotropic action of the plant adaptogens used to restore and strengthen the immune system in athletes after intense physical exertion is a priority area of the research in sports medicine.

The aim of the study was to investigate the effect intragastric administration of ginseng root extract (GRE) (ginsenosides) on immunity and regulation of energy metabolism in rats after exhausting physical exercise (EPE).

Material and methods. The study was conducted on 5 groups of male Wistar rats with an initial body weight of ≈250 g. Animals of the control (the 1^st) and experimental groups were placed on a treadmill for 20 min 3 times a week for 2 weeks, after the training was completed, an EPE test was performed (except for the control). 30 min before the training and EPE, rats of groups 3–5 were intragastrically administered GRE in physiological solution at doses of 2.7, 13.5 and 27.0 mg per 1 kg of body weight in terms of ginsenosides, respectively; animals of groups 1 and 2 – physiological solution. Animals were withdrawn from the experiment within 30 min after the cessation of EPE. Expression of CD45R, CD3, CD4, CD8a, CD161 receptors on rat peripheral blood lymphocytes was determined by direct immunofluorescence staining of whole blood cells using a panel of monoclonal antibodies on an FC-500 flow cytometer. A basic commercial kit was used to determine the levels of cytokines: interferon γ (IFN-γ), interleukin 1β (IL-1β), IL-4, IL-6, IL-10, IL-17A and tumor necrosis factor α (TNF-α), hormones leptin and ghrelin. Measurements were performed on a Luminex 200 multiplex analyzer using xMAP (multianalyte profiling) technology and Luminex xPONENT Version 3.1 software.

Results. EPE in rats caused changes in the composition of lymphocyte subpopulations, manifested in an increase in the relative content of CD8⁺ cytotoxic lymphocytes in the peripheral blood with a decrease in the immunoregulatory index (СD4⁺/CD8⁺). Increased plasma levels of pro-inflammatory cytokines (IL-17A and TNF-α) found in group 2 rats after EPE indicate the presence of inflammatory processes in damaged organs and tissues, including skeletal muscles. Intragastric administration of ginseng root extract to rats had a dose-dependent protective effect, as evidenced by normalization of the composition of lymphocyte subpopulations, a decrease in the levels of pro-inflammatory cytokines, an increase in the activity of Treg (regulatory T-lymphocytes) and Th2 (T-helpers type 2) with an increase in the production of IL-10 and IL-4, positive modulation of the IL-10/IL-17A ratio and restoration of the overall cytokine profile to control values. Ginseng root extract also has a positive effect on energy metabolism, in which regulation leptin and ghrelin participate. Administration of the maximum dose of ginseng root extract (27 mg/kg body weight) to rats induced activation of innate immunity, as evidenced by an increase in the relative content of NK and NKT cells in the peripheral blood.

Conclusion. The obtained results confirm the regulatory and normalizing effect of ginseng root extract (ginsenosides) on the immune status and energy metabolism of Wistar rats after EPE, which indicates the prospect of its use in stressful situations caused by physical overexertion in humans.

One of the approaches to the prevention and dietary correction of carbohydrate and lipid metabolism disorders is the development of new functional foods with the ingredients containing bioactive compounds with hypolipidemic and hypoglycemic properties. Soybean protein and biomass of Arthrospira platensis cyanobacteria containing phycobiliproteins (C-phycocyanin and allophycocyanin) are the sources of such bioactive compounds.

The aim of the research was to evaluate the combined effect of phycocyanin concentrate (in two dosages of 30 and 300 mg/kg body weight) and soy protein (50% of the protein in the diet) on disorders, induced in Wistar male rats by consumption of high-fat diet with 2% cholesterol.

Material and methods. A 108-day study was performed on 60 growing male Wistar rats. Animals of the control group K1 received a standard semi-synthetic diet. Disturbances in rats of the experimental group G2 were caused by increasing the proportion of the fat component in the diet (up to 29%), adding 2% cholesterol and replacing 20% of cornstarch with sucrose. In experimental groups G3, G4, and G5, 50% of casein in the high-fat diet was replaced with soy protein isolate. Additionally, phycocyanin concentrate was added to the diets of rats in groups G4 and G5 in quantities of 30 and 300 mg/kg of body weight (in terms of phycocyanin), respectively. In all animals, insulin resistance test was conducted, body composition was measured using magnetic resonance relaxometry, blood serum biochemical parameters of protein, lipid, purine metabolism and liver function, and the triglyceride and cholesterol liver levels were determined by spectrophotometric methods using a biochemical analyzer; leptin, ghrelin, C-peptide, insulin, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase and hydroperoxides were determined in blood serum using enzyme immunoassay.

Results. The inclusion of only soy protein isolate into the high-fat diet with cholesterol had a hypoglycemic effect, preventing the development of insulin resistance, and led to a reliable decrease in blood level of lipid peroxides (p=0.011) compared to G2 group. The combined introduction of phycocyanin concentrate at a dose of 300 mg/kg body weight and soy protein into the diet significantly reduced blood levels of cholesterol (p=0.022), lipid peroxides (p=0.001) and ALT activity (p=0.032) compared to G2. At the same time, animals of both these groups retained disorders in hormonal status (increased leptin and ghrelin level), antioxidant status (elevated level of MDA and SOD) at the same level as for animals consuming high-fat diet with 2% cholesterol. Phycocyanin concentrate at a dosage of 30 mg/kg body weight together with soy protein in the diet prevented the development of insulin resistance (p=0.049) and reduced serum glucose level (p=0.025); exerted an antioxidant effect, normalizing the level of lipid peroxides (p=0.047), MDA (p=0.015) and SOD (p=0.038), significantly reduced the level of leptin (p=0.037) and ghrelin (p=0.028) compared to animals consuming a high-fat diet with 2% cholesterol.

Conclusion. The results characterizing the absence of a beneficial effect of phycocyanins at a dose of 300 mg/kg body weight indicate their possible prooxidant effect, what requires further experimental research. The data on the beneficial effects of a low dose (30 mg/kg body weight) of phycocyanins in combination with soy protein on lipid and carbohydrate metabolism may be of interest for the development of functional food ingredients with hypoglycemic and hypolipidemic properties.

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in the world, especially among children. Studying the role of biomarkers in determining the course of NAFLD in obese children will make it possible to identify the disease at an early stage, assess the risks of progression and select individual approaches to therapy.

The purpose of the research was to study the diagnostic role of noninvasive biomarkers in determining the severity of liver steatosis and fibrosis in obese children.

Material and methods. 78 children from 11 to 17 years of age with exogenous constitutional obesity were examined. The children were divided into two groups: group 1 (n=59) – children with obesity and non-alcoholic fatty liver disease (NAFLD), group 2 (n=19) – children without NAFLD; in group 1, subgroups of children with simple liver steatosis (n=45) and non-alcoholic steatohepatitis (NASH) were identified (n=14). The study of lipid metabolism (total cholesterol, HDL, LDL, triglycerides), carbohydrate metabolism (glucose, insulin, HOMA-IR), blood serum level of fibroblast growth factor-21 (FGF-21), cytokeratin-18 (СK18), apoptosis factor associated with the FAS ligand (FASL), and visfatin has been conducted. All patients underwent ultrasound examination of the abdominal organs and liver elastography to determine the degree of liver fibrosis on the METAVIR scale and the degree of steatosis using a controlled attenuation parameter (CAP).

Results. The level of the biomarkers CK-18 and FASL were significantly higher in children from Group 1 compared to those without NAFLD (1.26 [0.44; 1.57] vs 0.47 [0.43; 0.59] ng/mL, p=0.008 and 36.33 [25.57; 45.94] vs 22.55 [20.27; 26.41] pg/mL, respectively). Moreover, these levels increased with the degree of obesity. In patients with NASH, FASL levels showed a positive correlation with the degree of obesity (r=0.40), CK-18 with the stage of liver fibrosis (r=0.50), and visfatin with transaminase activity (r=0.65), fibrosis (r =1.0), and hepatic steatosis degree (r=0.60). FGF-21 demonstrated only weak correlations with the other studied biomarkers. The HIS and APRI indices were significantly higher in patients with NASH (46.46 [40.75; 53] vs 42.11 [36.88; 47.09], p=0.0006 and 0.25 [0.18; 0.36] vs 0.18 [0.15; 0.21], p=0.04 in patients with hepatic steatosis; and vs 40.02 [36.4; 44.85] and 0.16 [0.12; 0.22] in patients from Group 2, respectively). All patients had PNFI>9, indicating the presence of significant fibrotic changes. Correlation analysis showed that HIS and APRI indices were strongly associated with the degree of steatosis, alanine aminotransferase activity, and right liver lobe size.

Conclusion. The use of biomarkers makes it possible to complement ultrasound diagnostics of NAFLD, providing more complete information about the severity of the disease without invasive procedures. The development and application of noninvasive methods for the diagnosis and prediction of NAFLD will in some cases avoid liver biopsy.

Currently, there is an increase in gluten-associated diseases. The range of food for such patients is currently quite limited. In this regard, the development of new gluten-free products, including those popular among consumers of flour confectionery, is relevant.

The purpose of the research was to develop a formulation and to evaluate the quality indicators of gluten-free biscuits intended for special dietary uses.

Material and methods. To prepare prototypes of gluten-free biscuits, corn flour, green buckwheat, steamed buckwheat and rice flour were used instead of wheat flour of the highest grade, along with unsalted butter, salt, baking soda, and white sugar. The experimental products were evaluated according to organoleptic (on a five-point scale), physical and chemical (mass fraction of moisture, alkalinity, wetness) and sanitary-microbiological parameters with calculation of nutritional and energy value.

Results. When developing gluten-free biscuits for the formation of various flavor profiles, wheat flour was 100% replaced with gluten-free flour: corn, rice, steamed buckwheat and green buckwheat. According to the results of an organoleptic assessment and analysis of physical, chemical, microbiological parameters, biscuits with green buckwheat flour, as well as a mixture of corn and rice flour (1:1) were selected. The calculation of the nutritive value showed that one serving of the product (30 g) allows to cover the daily requirement for protein, fats and carbohydrates by 3.0–5.5%, dietary fiber – by about 3%. Despite the slightly increased content of micronutrients in the developed biscuits, they cannot serve as their significant source. Only biscuits with green buckwheat flour can cover the need for phosphorus, iron and vitamins B₁ and PP by 5% or more in 1 serving.

Conclusion. The developed biscuits with green buckwheat flour for special dietary uses for people with gluten intolerance can serve a source of such micronutrients as phosphorus, iron, vitamins B₁ and PP.

Antibacterial therapy of the small intestine bacterial overgrowth (SIBO) is not effective enough and has a high relapse rate after treatment. Diet is a well-modifiable factor that plays a major role in shaping the composition, diversity, metabolic activity and stability of the intestinal microbiota. Intestinal bacteria ferment undigested food residues to form species-specific carbon-chain volatile organic compounds (VOCs).

The aim of this research was to study possible correlations between dietary variables and the level of stool VOCs in patients with hydrogen-producing SIBO.

Material and methods. The material of the study was the data of 100 patients referred for a hydrogen-methane breath test with lactulose in case of suspected presence of SIBO. Excessive bacterial growth of hydrogen-producing flora in the small intestine was determined by changes in the content of hydrogen and methane in exhaled air after consuming a portion of lactulose using the GastroCheck Gastrolyzer apparatus. The assessment of actual nutrition at home was carried out by 24-hour dietary recall. The determination of VOCs in patients’ feces was carried out using gas chromatography-mass spectrometry (a gas chromatograph equipped with a vapor-phase autosampler in combination with a triple quadrupole mass spectrometer).

Results. Of the 100 patients examined, 41 were found to have a overgrowth of hydrogen–producing flora, 15 had an excess of methanogenic flora, and 10 had an excess of both hydrogen-producing and methanogenic flora. No signs of SIBO were found in 34 patients and they formed a control group. When comparing dietary parameters expressed in absolute values, significant differences were found only in relation to dietary fiber: patients with SIBO differed in a lower level of their consumption (19.8±9.1 vs 25.5±12.3 g/ day, p=0.023). At the same time, the index of healthy nutrition HEI-2020 in the control group was significantly higher (52.9±11.1 vs 44.4±14.4%, p=0.003). Due to the high variability of VOC levels, no significant differences between the groups for individual VOCs have been established. The results of the analysis of the structure of correlations between 84 variables of the nutrition assessment of the studied participants and 80 VOCs in their stool showed significant interdependence differences between patients of the studied groups. In patients with SIBO, the metabolic activity of the microbiota changed most significantly when eating leafy greens, berries, oatmeal and sausages, and in the control group when eating potatoes, tropical fruits, buckwheat and eggs.

Conclusion. Thus, significant differences in the structure of correlations between dietary variables and the level of stool VOCs in patients with SIBO and the control group have been established.