Muscle Tissue Metabolism Research Articles

DEPENDENCE OF OXIDATIVE BALANCE AND CHOLESTEROL METABOLISM IN MUSCLE TISSUE ON EXERCISE INTENSITY

Intriduction. Changes in oxidative balance and lipid metabolism have the leading role in performance limitation, adaptation and maladaptation to physical activity. It is especially important to analyse the direction of metabolic changes at the subcellular level. The aim of the study is to examine the state of oxidative balance and cholesterol metabolism in muscle tissue at moderate and maximal swim-ming load. Material and methods. A comprehensive study of indicators for free-radical oxidation (content of diene conjugates, TBA-active products, chemilu-minescence intensity), antioxidant defense (total antioxidant activity, antiradical activity) and cholesterol metabolism in tissues of heart muscle and thigh muscle of white male rats at moderate and maximum swimming load was carried out. Results. The patterns of metabolic changes in muscle tissue depending on the intensity of muscular work have been established: these are the forms of compensated oxidative stress at moderate and decompensated at maximum load, against the background of decreasing cholesterol content. In cardiac tissue oxidative stress phenomena were less expressed, and changes in cholesterol content were multidirectional: a tendency to decrease at moderate load and a significant increase at maximum load. Conclusion. The reduction of antioxidant defence resources and intensification of free-radical oxidation reactions constitute one of the leading mecha-nisms for metabolic disorders due to extreme physical load, which is confirmed by reliable changes in the studied parameters. The complex study of indicators characterizing the processes of free-radical oxidation, antioxidant protection and cholesterol content is an informative criterion for the influ-ence of physical exercise on the organism. The obtained data allow us to recommend the inclusion of antioxidants in the complex prevention and ther-apy of acute physical overstrain.

Missing information on the link between cell death mechanisms and good eating quality in cultured myofoods

BackgroundCommercial interest in the production of cultured myoproducts (cultured “meat”) has grown in a broad range of companies. As has been shown with plant-based meat alternatives, consumer acceptance of such products will depend on their eating quality, as well as cost, ethical and sustainability issues. Scope and approachPrincipal factors in the sensory quality of conventionally-produced meat (texture, colour, flavour, juiciness) are very much affected by post-mortem metabolism in muscle tissue. However, there is a lack of information on how cell death and subsequent metabolism may affect the eating quality of cultured myoproducts. Key finding/hypothesisThe main mechanisms of cell death in cell culture are apoptosis, necrosis and autophagy. Knowledge of the conditions and pathways inducing these and other mechanisms of cell death provides a conceptual framework of how cell harvesting conditions could be used to manipulate post-mortem metabolism in cultured myoproducts. Because the structure, composition and protein isoforms present will differ in conventional meat versus cultured products, a key question will be whether the well-understood post-mortem metabolic processes in the conversion of muscle to meat are desirable, or should be altered, to achieve acceptable sensory qualities of cultured myoproducts. ConclusionPublished information on post-mortem metabolism in cultured muscle cells is entirely lacking. Although post-mortem metabolism will differ with specific cell line and bioreactor conditions, general studies in the area should provide important tools in manipulating the end-product quality of cultured myofoods.

A novel QTL region for pH and meat color in Duroc pigs.

One of the most important processes that occur during the transformation of muscle to meat is the pH decline as a consequence of the post-mortem metabolism of muscle tissue. Abnormal pH declines lead to pork defects such as pale, soft, and exudative meat. There is genetic variance for ultimate pH and the role of some genes on this phenotype is well established. After conducting a genome-wide association study on ultimate pH using 526 purebred Duroc pigs, we identified associated regions on Sus scrofa chromosomes (SSC) 3, 8, and 15. Functional candidate genes in these regions included PRKAG3 and PHKG1. The SSC8 region, at 71.6 Mb, was novel and, although no candidate causative gene could be identified, it may have regulatory effects. Subsequent analysis on 828 pigs from the same population confirmed the impact of the three associated regions on pH and meat color. We detected no interaction between the three regions. Further investigations are necessary to unravel the functional significance of the novel genomic region at SSC8. These variants could be used as markers in marker-assisted selection for improving meat quality.

Pharmaco-technological research and stability of the drug for the treat-ment and prevention of vitamin and trace element deficiency in animals

The article presents the research results on the Development of manufacturing technology and the study of the stability of a solution for oral use based on carnitine hydrochloride, vitamins – E, B12, choline chloride, selenium, and zinc. “Devivit Carnitine” oral is used for the prevention of diseases of liver and muscle tissue metabolism in farm animals and poultry, nephrosis, myocarditis, prevention of stress (heat, transport, sound, food, post-vaccination, etc.), and prevention of vitamin and hypovitaminosis. When developing the drug technology, experimentally obtained pharmaco-technological properties of active substances and excipients were taken into account. The technological process of preparing an oral solution consists of four technological stages: preparation of canisters for filling, preparation of the solution, filling containers with medicine and packaging. The stability and shelf life of “Devivit Carnitine” (solution for oral use) in plastic canisters were determined. It was established that the drug sample in plastic canisters was stable, according to all quality control methods indicators, during the entire period of the study. The shelf life of the medicinal product with carnitine hydrochloride, vitamins E and B12, choline chloride, selenium, and zinc is 12 months. In the future, a study of preclinical data is planned to verify whether the drug does not reveal a particular hazard for animals based on conventional studies of safety pharmacology, repeated dose toxicity, genotoxicity, carcinogenicity, and developmental toxicity.

Effects of high-calorie diet-induced visceral obesity on reproductive hormones and muscle tissues in male and female Wistar rats

Overweight and obesity are associated with alterations in the reproductive system, which affect the anabolic supply to peripheral muscle tissues. The study aimed to investigate the effects of a high-calorie diet (HCD) on the development of obesity, reproductive hormone levels, and morphofunctional characteristics of muscle tissues in Wistar rats (i.e., 54 sexually mature male and female Wistar rats) for 16 weeks. Male rats fed with an HCD displayed (i) visceral obesity and hypogonadism, (ii) a decrease in the mass of the musculus triceps surae, (iii) increased levels of total protein, cholesterol, glucose, lactate, lactate dehydrogenase, and malonic dialdehyde (MDA) and superoxide dismutase (SOD) activities, and (iv) stable concentrations of estradiol and testosterone in the muscle tissues. In contrast, female rats fed with HCD displayed (i) visceral obesity, (ii) alterations in reproductive hormones toward hyperandrogenism, (iii) decreased metabolism in the muscle tissues, and (iv) increased levels of estradiol and MDA (without SOD activation). The cross-sectional area of the muscle fiber was significantly reduced by 20% in male and 44% in female rats on HCD. In addition, the total muscle edema was reportedly increased by twofold in both male and female rats. In summation, obese male and female rats developed an imbalance of reproductive hormones and alterations in muscle tissue metabolism.

Genomic insights into the contribution of de novo lipogenesis to intramuscular fat deposition in chicken

IntroductionThe proportion of animal based foods in daily diet of consumers is constantly increasing, with chicken being highly favored due to its high protein and low fat characteristics. The consumption of chicken around the world is steadily increasing. Intramuscular fat (IMF) is a key indicator affecting meat quality. ObjectHigh IMF content can contribute to improve the quality of chicken meat. The regulatory mechanism of IMF deposition in chicken is poorly understood, so its complete elucidation is essential to improve chicken meat quality. MethodHere, we performed whole genome resequencing on 516 yellow feather chickens and single-cell RNA sequencing on 3 63-day-old female JXY chickens. In addition, transcriptome sequencing techniques were also performed on breast muscle tissue of JXY chickens at different developmental stages. And 13C isotope tracing technique was applied. ResultsIn this study, a large-scale genetic analysis of an IMF-selected population and a control population identified fatty acid synthase (FASN) as a key gene for improving IMF content. Also, contrary to conventional view, de novo lipogenesis (DNL) was deemed to be an important contributor to IMF deposition. As expected, further analyses by isotope tracing and other techniques, confirmed that DNL mainly occurs in myocytes, contributing about 40% of the total fatty acids through the regulation of FASN, using the available FAs as substrates. Additionally, we also identified a relevant causal mutation in the FASN gene with effects on FA composition. ConclusionThese findings contribute to the understanding of fat metabolism in muscle tissue of poultry, and provide the feasible strategy for the production of high-quality chicken meat.

Peculiarities of the relationship between the terminal site of glycolysis and the initial segment of gluconeogenesis in the myocardium and skeletal muscles of animals irradiated at different doses

Existing types of muscles differ not only structurally, but also metabolically (direction of energy exchange, choice of biosubstrates, dependence on the action of mediators, hormones, etc.). A number of studies have been devoted to the study of the impact of ionizing radiation on metabolism in muscle tissue. After irradiation, thickened muscle cells with enlarged nuclei appear in the heart muscle, the number of which does not decrease for 6 months, which indicates a violation of nuclear-cytoplasmic relations in myocardial cells. Phosphoenolpyruvate carboxykinase which ensures the utilization of cytoplasmic oxaloacetate and its transformation into phosphoenolpyruvate, completes the initial stage of gluconeogenesis and can limit the rate of gluconeogenesis from lactate. It should be emphasized that phosphoenolpyruvate carboxykinase is more active in skeletal muscles, where the activity of pyruvate kinase and lactate dehydrogenase is increased. The purpose of the work is to investigate the peculiarities of the relationship between the terminal site of glycolysis and the initial segment of gluconeogenesis in the myocardium and skeletal muscles of animals irradiated at different doses. The authors proved that in animals irradiated at a dose of 0.5 Gy, the activity of pyruvate kinase in the myocardium and skeletal muscle increases compared to intact animals. In the blood, on the contrary, there is a decrease in the activity of this enzyme compared to intact animals. When animals are irradiated at a dose of 1.0 Gy, diametrically opposite changes are observed. When animals are irradiated at a dose of 0.5 Gy, there is a slight decrease in the activity of lactate dehydrogenase in the myocardium and blood against the background of an increase in the activity of this enzyme in skeletal muscle. Irradiation of animals at a dose of 1.0 Gy leads to an acute increase in lactate dehydrogenase activity in the myocardium and skeletal muscle. The data obtained revealed that in animals irradiated at a dose of 0.5 Gy, the activity of phosphoenolpyruvate carboxykinase in skeletal muscle increases, while in cardiac muscle, on the contrary, its activity decreases as well as in blood. With an increase in the radiation dose to 1.0 Gy, diametrically opposite changes in the activity of phosphoenolpyruvate carboxykinase are observed. The authors concluded that outlined changes in the waу of intramuscular glycolysis and gluconeogenesis reactions show the pathophysiologcal mechanisms of biochemical supply restructuring as the result of ionizing irradiation influence. From the fundamental point of view these results show the direction of pathophysiologically oriented pharmacological correction of radiation-provoked muscle disturbances.

PARAMETERS OF OXIDATIVE BALANCE AND CHOLESTEROL METABOLISM IN MUSCLE TISSUE DURING PROLONGED RESTRICTION OF MOTOR ACTIVITY

Actuality. The leading role in the pathogenesis of metabolic disorders in hypokinesia is performed by disorders of oxidative balance and lipid metabolism. Especially important are studies of metabolic disorders at subcellular level. The aim of the study is to investigate oxidative balance and cholesterol metabolism in muscle tissue under motor activity restriction of different duration. Material and methods. Comprehensive investigation of free radical oxidation parameters (diene conjugates, ТBA contents, intensity of chemiluminescence), antioxidant protection (total antioxidant activity, antiradical activity) and cholesterol metabolism in heart muscle and thigh muscle tissues of white male rats under movement restriction during up to 28 days, which was achieved by placing animals in individual 40 cm2 cells. Results. The patterns of metabolic changes in the muscle tissue depending on the duration of motor activity restriction were established in the form of free radical oxidation intensification, reduction of antioxidant protection resources and increase of cholesterol content in the heart muscle. These metabolic changes were expressed most prominently on the 14th to 21st days of the experiment. In addition to violations of the oxidant balance, a specific feature of changes in cholesterol content in the thigh muscle was a wave-like change of this index in the form of an increase on the 7th day of the experiment, followed by a decrease with minimal values on the 21st day of the experiment. Conclusion. Decrease in antioxidant protection resources and intensification of free-radical oxidation reactions constitute one of the leading mechanisms of metabolic disturbances in restricting motor activity, which is confirmed by significant changes of the studied indicators. Comprehensive study of the indicators characterizing the processes of free-radical oxidation, antioxidant protection and cholesterol content is an informative criterion of the effects of hypokinesia on the body, and the obtained data allow the inclusion of antioxidants in the complex prevention and therapy in forced limitation of motor activity. The author declares that there is no conflict of interest in the performance of this work.

Acadesine supplementation in a soybean oil-based diet remodels hepatic lipid and glucose metabolism in juvenile large yellow croaker (Larimichthys crocea)

Dietary high soybean oil (SO) inclusion leads to excessive hepatic lipid accumulation and metabolism disorder in fish species. This study was conducted to investigate the effects of adenosine 5’-monophosphate-activated protein kinase (AMPK) pathway activation by acadesine (AICAR) on hepatic histology and metabolism-related gene expression of juvenile large yellow croakers (Larimichthys crocea) fed with SO-based diet. In this study, fish (initial body weight 3.89 ± 0.02 g) were fed fish oil (FO)-based, SO, or SOA (SO diet supplemented with 100 mg kg−1 AICAR) diets with three replicates of each treatment for 70 days. In general, the replacement of dietary FO with SO led to excessive hepatic lipid accumulation and a glucose metabolism disorder. Histological sections and biochemical analysis of hepatic tissue consistently revealed that AICAR supplementation could partly ameliorate SO-induced excessive hepatic lipid accumulation, probably by suppressing the expression of genes related to fatty acid uptake and lipogenesis while enhancing the expression of lipolysis-related genes. Nevertheless, AICAR regulated lipid metabolism in muscle tissue in an inverse pattern to that in hepatic tissue, indicating that muscle tissue could attempt to mitigate lipid accumulation by improving lipolysis in response to the dietary inclusion of SO. Dietary AICAR partly improved glucose metabolism by reducing the expression of genes related to gluconeogenesis in hepatic tissue while increasing the expression of genes related to glucose uptake and glycolysis in muscle tissue. Collectively, dietary AICAR mitigated excessive hepatic lipid accumulation and glucose metabolism disorder. The amelioration of hepatic lipid accumulation by AICAR is likely caused by increasing lipid catabolism and decreasing lipid anabolism. The improved glucose metabolism by AICAR may be ascribed to decreased hepatic gluconeogenesis, as well as increased muscle glucose uptake and utilization.

RNA-Seq Study on the Longissimus thoracis Muscle of Italian Large White Pigs Fed Extruded Linseed with or without Antioxidants and Polyphenols

The addition of n-3 polyunsaturated fatty acids (n-3 PUFAs) to the swine diet increases their content in muscle cells, and the additional supplementation of antioxidants promotes their oxidative stability. However, to date, the functionality of these components within muscle tissue is not well understood. Using a published RNA-seq dataset and a selective workflow, the study aimed to find the differences in gene expression and investigate how differentially expressed genes (DEGs) were implicated in the cellular composition and metabolism of muscle tissue of 48 Italian Large White pigs under different dietary conditions. A functional enrichment analysis of DEGs, using Cytoscape, revealed that the diet enriched with extruded linseed and supplemented with vitamin E and selenium promoted a more rapid and massive immune system response because the overall function of muscle tissue was improved, while those enriched with extruded linseed and supplemented with grape skin and oregano extracts promoted the presence and oxidative stability of n-3 PUFAs, increasing the anti-inflammatory potential of the muscular tissue.

Молочна кислота як системний продукт метаболізму та біомаркер фізичного навантаження

This paper presents an up-to-date review of research data on the specific features of lactic acid metabolism and its role as an effector of vital regulatory mechanisms. Lactic acid is an alpha-hydroxy monocarboxylic acid. Physical loads of submaximal intensity and some diseases can cause dramatic increase of lactic acid content in the body fluids. The excessive lactate is removed from the working muscle and either metabolized by other tissues or excreted from the human body. Alteration of the lactate-pyruvate balance is one of the main markers of the development of cardiac hypertrophy and failure. The redistribution of lactate between the cells producing it and the cells that metabolize it is vital to maintain a stable pH level in tissues and hold lactate in the body since this compound is an important energy source as well as an effector of important regulatory mechanisms. The quantification of lactate is used to assess general physical capabilities of the human body, the intensity of physical load and the rate of recovery in physical rehabilitation. Specialized proteins, which refer to the group of monocarboxylate transporters, are involved in lactate excretion and absorption by cells. The presence of various types of transporters in cell membranes that differ in affinity to lactate and the direction of transport ensures a rapid redistribution of lactic acid throughout the body and regulates the intensity and direction of its metabolism according to the physiological needs. Efficient transfer and redistribution of lactate between different tissues of the body is essential, given the participation of lactate in several important regulatory mechanisms. As an effector, lactate is involved in the regulation of angiogenesis, differentiation of myosatellitocytes, regeneration of muscle fibers, polarization of macrophages and the course of inflammatory processes. Besides, lactate participates in epigenetic mechanisms of muscle tissue metabolism regulation. Therefore, lactate is one of the key metabolites in the human body.

CHANGES IN HEMATOLOGICAL BLOOD PARAMETERS IN HORSES PARTICIPATING IN EQUESTRIAN DISTANCE RUNS

The article provides information on the impact of training on clinical blood parameters in horses participating in equestrian distance running competitions, the distance length is 40 km. The animals were divided into two groups, 10 heads each. The first group included horses that were trained one week before the races, the second included animals that were trained two weeks before the competition. As a result of the research, it was revealed that in the case of training within one week before the competition, horses had a statistically significant increase in the number of segmented neutrophils compared to the indicators before the start. This is probably due to the fact that with heavy physical exertion, muscle tissue begins to be injured in insufficiently trained animals, as a result of which the body needs to dispose of the products of muscle tissue metabolism. During the training for two weeks before the competition at a distance of 40 km, the level of segmented neutrophils in the blood of horses did not differ from the data before the start. An increase in red blood indicators was determined in all experimental horses after the runs, when compared with the data before the load, but these indicators did not go beyond the reference values. This is probably due to dehydration, which often develops when walking a long distance. There was also a statistically significant decrease in the level of lymphocytes after exercise in both groups of horses when compared with the indicators before the start. At the same time, these indicators did not go beyond the reference interval.

Ostarine-Induced Myogenic Differentiation in C2C12, L6, and Rat Muscles.

Ostarine (also known as enobosarm or Gtx-024) belongs to the selective androgen receptor modulators (SARMs). It is a substance with an aryl-propionamide structure, classified as a non-steroidal compound that is not subjected to the typical steroid transformations of aromatization and reduction by α5 reductase. Despite ongoing research on ostarine, knowledge about it is still limited. Earlier studies indicated that ostarine may affect the metabolism of muscle tissue, but this mechanism has not been yet described. We aimed to investigate the effect of ostarine on the differentiation and metabolism of muscle. Using C2C12 and L6 cells, as well as muscles obtained from rats administered ostarine, we showed that ostarine stimulates C2C12 and L6 proliferation and cell viability and that this effect is mediated by androgen receptor (AR) and ERK1/2 kinase activation (p < 0.01). We also found that ostarine stimulates muscle cell differentiation by increasing myogenin, MyoD, and MyH expression in both types of cells (p < 0.01). Moreover, pharmacological blocking of AR inhibits the stimulatory effect of ostarine. We further demonstrated that 30 days of ostarine administration increases myogenin, MyoD, and MyH expression, as well as muscle mass, in rats (p < 0.01). Based on our research, we conclude that ostarine stimulates muscle tissue proliferation and differentiation via the androgen receptor.

Arsenic Toxicity on Metabolism and Autophagy in Adipose and Muscle Tissues.

Arsenic, a naturally occurring metalloid derived from the environment, has been studied worldwide for its causative effects in various cancers. However, the effects of arsenic toxicity on the development and progression of metabolic syndrome, including obesity and diabetes, has received less attention. Many studies suggest that metabolic dysfunction and autophagy dysregulation of adipose and muscle tissues are closely related to the development of metabolic disease. In the USA, arsenic contamination has been reported in some ground water, soil and grain samples in major agricultural regions, but the effects on adipose and muscle tissue metabolism and autophagy have not been investigated much. Here, we highlight arsenic toxicity according to the species, dose and exposure time and the effects on adipose and muscle tissue metabolism and autophagy. Historically, arsenic was used as both a poison and medicine, depending on the dose and treatment time. In the modern era, arsenic intoxication has significantly increased due to exposure from water, soil and food, which could be a contributing factor in the development and progression of metabolic disease. From this review, a better understanding of the pathogenic mechanisms by which arsenic alters metabolism and autophagy regulation could become a cornerstone leading to the development of therapeutic strategies against arsenic-induced toxicity and metabolic disease.

The impact of chronic kidney disease on muscle tissue metabolism in patients undergoing hemodialysis

Objective: to estimate the prevalence of sarcopenia and evaluate the contribution of myostatin and mTOR to the development of muscle mass loss and strength in patients with end-stage renal disease treated with program hemodialysis. Materials and methods: the study included 80 patients with CKD5D, the average age of study participants was 51.7±11.6 years. In all patients, anamnestic data were analyzed, the results of laboratory and instrumental examination were evaluated, the levels of myostatin and mTOR in the blood serum were determined, hand dynamometry, bioimpedancemetry, and a leg raising test were performed. Results: the average volume of muscle mass in the subgroup with sarcopenia was 20.5±0.7 kg and significantly differed from that in the subgroup without sarcopenia 25.23±0.8 kg (p &lt;0.05). The prevalence of sarcopenia in the general group was 38.75%. In men, decreased muscle mass was statistically significantly more common than among women (p &lt;0.05). The level of mTOR in the blood serum of patients with sarcopenia was significantly lower than that in the subgroup without sarcopenia (6.61±0.4 ng/ml and 9.4±0.3 ng/ml, respectively (p &lt;0.001)). The level of myostatin was significantly higher in the subgroup of patients with sarcopenia than without it (12.2±0.6 ng/ml vs. 8.1±0.3 ng/ml, respectively (p &lt;0.001)). The increase in myostatin was accompanied by a decrease in mTOR both in the general group (r=-0.57) and in the subgroup of patients with sarcopenia (r=-0.55). Conclusion: A high prevalence of sarcopenia was found in patients with CKD receiving renal replacement therapy. Myostatin and mTOR have demonstrated their diagnostic potential and can be used as promising markers for the verification of sarcopenia.

The significance of ferritin as one of the markers of inflammation

Iron is an extremely important trace element that plays a large role in oxygen transport, DNA synthesis and muscle tissue metabolism. Ferritin is a protein compound inwhich iron is deposited as a reserve for the body; in laboratory diagnostics, it is usually evaluated as a marker of iron content, and the determination of its concentration is used to diagnose iron deficiency conditions. It structurally consists of the protein apoferritin and the ferric atom in the composition of phosphate hydroxide. One ferritin molecule can contain up to 4,000 iron atoms. The ferritin content in blood is measured in nanograms per milliliter. The normal concentration for men is 29–397 ng/ml, and for women, it is 6–159 ng/ml. A decrease in the level of ferritin in the blood is possible in iron deficiency, but an increase in its concentration may indicate not only the development of hemochromatosis, but also, along with C-reactive protein, be a marker of an active inflammatory reaction. An increase in the synthesis of C-reactive protein, fibrinogen, ferritin, serum amyloid by hepatocytes occurs under the influence of pro-inflammatory cytokines IL-6, IL-18, IL-1, TNF in severe acute processes, especially in the case of their viral etiology.

Effects of cool resistance exercise on oxygen metabolism in muscle tissue and clinical application

Resistance training is beneficial for elite athletes and the elderly, alike. It plays a key role in healthy ageing, helping retain muscle mass, and it can also help reduce the chances of chronic diseases such as osteoporosis and high blood pressure. In order for resistance exercise to be effective, there is an ongoing need for proven techniques that can assist with their resistance training. Professor Masahiro Goto, Director of the Department of Physical Therapy, Aino University, Japan, works to understand the physiological dynamics at play during resistance exercise with a view to developing novel exercise methods and using new technologies to improve resistance exercise outcomes. A brief intramuscular hypoxic state is key to promoting muscle growth and this has therefore been a target for improving resistance techniques, but a challenge arises in terms of monitoring hypoxia. That is why Goto is looking to establish a method that can accurately, quickly and cheaply test the intramuscular oxygenation state during resistance exercise. Recognising the potential of near infrared spectroscopy (NIRS), he performed a study on volunteers who have resistance exercise carrier more than one year over eight weeks to find out whether NIRS can be used as an effective measure of internal muscular oxygenation levels and if cold pack treatment of muscles prior to exercise results in better muscle mass gain. He used electromyograms to measure muscle contraction, ultrasound to monitor changes in muscle mass and arterial oxygen saturation measurements to elucidate oxygenation levels. He found that NIRS was effective for routine monitoring of oxygen levels and that cold pack treatment during resistance exercise causes higher muscle activity and creates a more hypoxic muscular environment than without any cold treatment.

Effect of fasting on protein metabolism in muscle tissue of Larimichthys crocea revealed by transcriptome and proteome

Effect of fasting on protein metabolism in muscle tissue of Larimichthys crocea revealed by transcriptome and proteome

Вплив бурштинової кислоти на зміни мітохондрільного апарату клітин скелетних м᾽язів при моделюванні фізичних навантажень в експерименті

Today, a search in the experiment and practice of sports training of pharmacological agents, which at various levels of organization of the living organism, including both muscle tissue and muscle cells, were able to mitigate the negative consequences ofsuper-intense long-term physical loads, does not have to stop. One such universal means is succinic acid, which is a natural metabolite of the Krebs cycle, and, therefore, directly related to the mechanisms of energy generation in the body. Since this process in cells, and muscle tissue cells is no exception, it takes place in mitochondria. The definition of the structural-functional rearrangements of the mitochondrium of myocytes during physical loads is very interesting especially when succinic acid is used as an organoprotector. Material and methods. Physical load was simulated for three weeks in rats by swimming with an additional load. 10 intact animals served as control, and the remaining 20 were equally divided into two study groups, the first was with physical load and the second group had the same load application of succinic acid in a daily dosage of 2.5 mg per animal weighing 220-250 g, based on the corresponding extrapolation of dosages to an adult human. Research on experimental animals was carried out in compliance with all norms of bioethics. Electron microscopic studies were carried out on the material of the tissue gastrocnemius’ muscle. Results and discussion. The results of the studies showed that hypoxia of the subcompensated load was found in the cells of this tissue, as well as activation of mitochondrial morphogenesis by 58.3% and 69.0% in both the subsarcoleal and the intraamyofibrillic subpopulations, respectively. In the experiment we established an increase in the number of membrane structures and an increase in the average diameter of mitochondria, leading to an increase in the energy capacity of the mitochondrium. These phenomena can be attributed to compensatory-adaptive changes under the influence of physical load. The application of succinic acid activates these processes to an even greater extent, i.e. the application of this pharmacological agent has a powerful protective effect on the optimization of energy metabolism of muscle tissue under physical loads. Thus, it showed that succinic acid contributed to the reduction of the structural signs of endothelial and mitochondrial dysfunction, contributing, in accordance to its known properties, optimization of energy metabolism and preservation of the integrity of mitochondria with levelling of the structural manifestations of mitochondrial dysfunction. This, in turn, leads to the optimization of macroergs products and hence increases in physical performance. Conclusion. The stated facts at a new level of development of science prove the expediency and effectiveness of using succinic acid and pharmacological agents based on it in order to improve the functional state of the body of athletes and their motor qualities

Development of a methodology to categorize poultry meat affected by deep pectoral myopathy

The growth of poultry production has led to an increase in the incidence of internal defects in chicken and turkey broilers, such as Deep Pectoral Myopathy (DPM). DPM is an ischemic hemorrhage or necrosis caused by the inadequate blood supply of Pectoralis minor and major muscles. Currently, visual appearance is the only parameter used to categorize the damage level. The aim of this research was to develop a scientific methodology to determine the level of damage in poultry breast tenders affected by this myopathy. For this purpose, microstructure, pH, protein and ion contents, and color were studied. Results allowed identifying three damage levels: normal, hemorrhagic samples with hematomas and blood clots, and necrotic tissues, based on significant variables (p < .05) measured in Pectoralis minor (pH, L* and a*), where muscles with myopathy presented L* values lower than 47, and necrotic muscles presented pH values higher than 6.05. Practical applications The appearance of defects in chicken meat is a growing problem due to the intensive genetic selection and the fast growth rate that the poultry industry demands. This research provides a scientific methodology, based on biochemical and physicochemical parameters of muscle tissue metabolism, and develops and validates a categorization for deep pectoral myopathy in broilers based on the level of muscle damage. This work, provides an objective and scientific methodology, and coupled with the work published in Traffano-Schiffo et al. (2018) and patented, will allow detecting, identifying, and characterizing chickens that have suffered deep pectoral myopathy and the degree of damage.