Proteins In Muscle Tissue Research Articles

Gamma Secretase Inhibitors as Potential Therapeutic Targets for Notch Signaling in Uterine Leiomyosarcoma.

Uterine leiomyosarcoma (uLMS) is a rare and aggressive cancer with few effective therapeutics. The Notch signaling pathway is evolutionarily conserved with oncogenic properties, but it has not been well studied in uLMS. The purpose of our study was to determine expression of Notch family genes and proteins and to investigate the therapeutic effect of γ-secretase inhibitors (GSIs), indirect inhibitors of Notch signaling, in uLMS. We determined expression of Notch genes and proteins in benign uterine smooth muscle tissue, fibroids, and uLMS samples by immunostaining and in two uLMS cell lines, SK-UT-1B (uterine primary) and SK-LMS-1 (vulvar metastasis) by RT-PCR, Western blot and immunostaining. We exposed our cell lines to GSIs, DAPT and MK-0752, and measured expression of HES1, a downstream effector of Notch. Notch proteins were differentially expressed in uLMS. Expression of NOTCH3 and NOTCH4 was higher in uLMS samples than in benign uterine smooth muscle and fibroids. Expression of NOTCH4 was higher in SK-LMS-1 compared to SK-UT-1B. Exposure of SK-UT-1B and SK-LMS-1 to DAPT and MK-0752 decreased expression of HES1 and decreased uLMS cell viability in a dose- and time-dependent manner that was unique to each GSI. Our findings suggest that GSIs are potential therapeutics for uLMS, albeit with limited efficacy.

INFLUENCE OF PARAMETERS OF MARINATING MEAT SEMI-FINISHED PRODUCTS ON THE QUALITY OF THE FINISHED PRODUCT

Improvement and introduction of modern technologies in the creation of new types of meat semi-finished products, the study of promising components and the development of new recipes for marinades, improving the organoleptic and taste properties of the final product is a relevant and promising area of research. Therefore, this study is focused on the influence of marinating parameters in the technology of meat semi-finished products, namely on the organoleptic, physicochemical, and functional-technological properties of the finished product. To solve the tasks, generalisation, comparison and the following research methods were used: organoleptic evaluation of appearance, cut section, taste, smell, colour, consistency, and juiciness; moisture content – by drying samples in a drying oven at a temperature of 103 ± 2 °C to a constant mass; fat content – by the Soxhlet method; ash content – by the conventional weighing method; determination of protein content – by the Kjeldahl method; the yield of the finished product was determined by weighing before and after heat treatment; moisture binding and moisture retention capacity was determined by pressing. The studies found that the effect of the duration of marinating significantly affects the organoleptic characteristics. Thus, the organoleptic characteristics and taste and aroma properties of the finished product when using honey in marinades improve, and the appearance becomes more attractive. According to the results of the organoleptic evaluation, the finished product, after 24 hours of marinating, received a score of 4.9 points. Also, in these samples were observed greater water retention and water binding capacity, which contributes to increased hydration and solubility of muscle tissue proteins. The influence of marinating parameters on the consumptive properties of the product has been established. Thus, the yield of finished baked beef after 24 hours of ageing in the marinade was the highest in sample No. 1 (marinade based on citrus honey – 10 g) and amounted to 84.96%, while the average weight yield of other samples was in the range of 73.18-77.5%. The obtained research results make it possible to expand the range of semi-finished products, correct organoleptic properties and enrich the finished product with biologically active substances

Uncoupling Proteins in Striated Muscle Tissue: Known Facts and Open Questions.

Significance: Uncoupling proteins (UCPs) are a family of proteins that allow proton leakage across the inner mitochondrial membrane. Although UCP1, also known as thermogenin, is well known and important for heat generation in brown adipose tissue, striated muscles express two distinct members of UCP, namely UCP2 and UCP3. Unlike UCP1, the main function of UCP2 and UCP3 does not appear to be heat production. Recent Advances: Interestingly, UCP2 is the main isoform expressed in cardiac tissues, whereas UCP3 is the dominant isoform in skeletal muscles. In the past years, researchers have started to investigate the regulation of UCP2 and UCP3 expression in striated muscles. Furthermore, concepts about the proposed functions of UCP2 and UCP3 in striated muscles are developed but are still a matter of debate. Critical Issues: Potential functions of UCP2 and UCP3 in striated muscles include a role in protection against mitochondria-dependent oxidative stress, as transporter for pyruvate, fatty acids, and protons into and out of the mitochondria, and in metabolic sensing. In this context, the different isoform expression of UCP2 and UCP3 in the skeletal and cardiac muscle may be related to different metabolic requirements of the two organs. Future Directions: The level of expression of UCP2 and UCP3 in striated muscles changes in different disease stages. This suggests that UCPs may become drug targets for therapy in the future. Antioxid. Redox Signal. 37, 324-335.

Nutrient adequacy and safety of functional lamb enriched with microelements

The article presents the results of studies of the amino acid composition and the concentration of trace elements in the meat of sheep of the Edilbaevsky breed when introducing feed additives containing essential trace elements into the diet. It was found that muscle tissue protein is saturated with an extremely important source of energy - alanine, its content varies in the studied groups from 0.71 to 0.76 g / 100 g of the product. The highest iodine content was found in the II - 54.6 ±6.8 mcg/kg and III - 61.5±9.6 mcg/kg experimental groups, the smallest amount of iodine was contained in the meat of animals of the control group.

Effects of Bacillus subtilis on growth performance and intestinal flora of Penaeus vannamei

In this article,It is of great significance to reduce the use of antibiotics and improve the efficiency of aquaculture. With companion feeding, Penaeus vannamei was fed with different concentrations of Bacillus subtilis. After feeding for 30 days, we weighed them to detect their growth performance, took hepatopancreas and blood samples to measure alanine aminotransferase, aspartate aminotransferase α-amylase, phenol oxidase, superoxide dismutase and peroxidase, and the content of crude protein in muscle tissue were measured. The result showed that adding 0.5% of B. subtilis to the feed has the best effect. When analyzing the intestinal flora, we found that the Proteobacteria and Firmicutes as the dominant phyla have significant differences compared with the control group. According to the Shannon diversity index, it can be seen that as the concentration of probiotics increases, the abundance of intestinal flora also tends to increase. According to different UPDMA cluster branches, it can be seen that there may be an enrichment of the same genus among groups. When the concentration of probiotics is 1%, the concentration of probiotics has a greater impact on the function of the intestinal flora.

Effect of 4 weeks of High-Intensity Interval Training on P53 and Caspase-3 Proteins Content in the Heart Muscle Tissue of Rats with Type 1 Diabetes

Introduction: Type 1 diabetes can lead to muscle apoptosis and a defect in the structure of the heart tissue. One of the main pathways of apoptosis is the pathway activated by the P53 and Caspase-3 proteins. Therefore, the aim of this study was to investigate the effect of 4 weeks of high intensity interval training on the content of P53 and Caspase-3 proteins in heart muscle tissue of Sprague-Dawley rats with type 1 diabetic rats. Methods: In this experimental study, twelve 2-month-old Sprague-Dawley male rats with mean weight of 300±20 gr were selected and after induction of diabetes through streptozotocin solution, randomly divided into 2 groups: experimental (n= 6) and control (n= 6). The training program consisted of 5 stages of 4-minute with an intensity of 85 to 95% of the maximum speed and 3-minute active rest periods with an intensity of 50 to 60% of the maximum speed. Proteins were measured by Western-Blot in vitro. SPSS software version 16 and independent t-test were used to analyze the data. Results: High intensity interval training resulted in a significant reduction in the P53 protein content of the training group compared to the control group (P=0.003). However, there was no significant change in the content of Caspase-3 in the activated form (P=0.71) and the initial form (P=0.15) in the training group compared to the control group. Conclusion: High intensity interval training, by reducing the content of the P53 protein and preventing the activation of the caspase-3 protein, may have inactivated the apoptosis pathway of these two proteins in heart cells in type 1 diabetic subjects.

Meat productivity and biological value of meat in bulls of various breeds

Our study presents the results of a comparative assessment of meat productivity and biological value of meat in bulls of various breeds. The work was carried out at OJSC named after N.E. Tokarlikov of the Almetyevsk region of the Republic of Tatarstan using industrial technology in three groups (18 heads in each group): I - Simmental, II - Black-and-White and III - Hereford. Relatively high rates of meat productivity and qualitative characteristics of the meat were determined in Hereford bulls: meat weight was 1.7 and 4.5% more compared with Simmental and Black-and-White peers. The meat index in animals of the meat direction (4.59) is higher by 7.5 and 5.5% compared to analogues of I and II groups. The specific gravity of the protein did not have significant differences (18.60-19.05%). At the same time, a higher level of fat was noted in meat from beef cattle - by 1.05 and 1.51%. They also favorably differed in essential amino acids content in the proteins of muscle tissue. Their amino acid score was above 100%. A more balanced ratio of essential amino acids was established in individuals of beef cattle when calculating the biological value of the protein. Meat from animals of Hereford breed was differed by relatively high level of non-essential amino acids - 318.8 mg per 1 g of protein, which is 1.3 and 10.4% more than in the peers of the first two groups.

СРАВНИТЕЛЬНАЯ ХАРАКТЕРИСТИКА АМИНОКИСЛОТНОГО СКОРА БЕЛКОВ МЯСА БАРАНЧИКОВ ПРИ ОБОГАЩЕНИИ РАЦИОНОВ ЭССЕНЦИАЛЬНЫМИ МИКРОЭЛЕМЕНТАМИ

The quality of meat, first of all, characterizes the proteins of muscle tissue. The amino acid composition and the ratio of essential amino acids are the main indicators of the biological potential of a protein. In the work, a scientific and economic experiment was carried out on the use of feed additives with trace elements selenium and zinc in the diet of rams. This article describes the effect of additives «Yoddar-Zn» and «DAFS-25», enriched with essential elements, on the biological value of the meat of young sheep of the Edilbaev breed. Quantitative indicators of essential amino acids were determined in a laboratory, which indicated the usefulness of the protein of this type of meat for all studied groups of animals. The protein of experimental animals contained all the essential amino acids necessary for the life of the organism. The minimum amino acid score was calculated for each group of rams. The obtained data fixed different limiting amino acids in the studied groups. The highest value of the minimum score was observed in lambs of the third experimental group due to the amino acid leucine. It was concluded that animals that consumed a dietary supplement with zinc and selenium in the composition had a higher potential for using meat protein for plastic purposes, which is expected to be absorbed by the human body by 87%.

Differential Gene Expression in Cell Types of the Human Skeletal Muscle: A Bioinformatics-Based Meta-Review

PURPOSE: This study evaluates the differences in the expression of genes frequently analyzed in the field of exercise science between the skeletal muscle tissue and various cell types that comprise the skeletal muscle tissue.METHODS: We summarized the genes and proteins expressed in the skeletal muscle that were published in “Exercise Science” journal from 2015 to present. Thereafter, we selected 15 genes and proteins that were the most analyzed genes and proteins in the skeletal muscle. These genes and proteins were horizontally compared for expression differences in skeletal muscle components and cultured cells based on NCBI Gene Expression Omnibus DataSets.RESULTS: The most analyzed genes (encoding analyzed proteins) in skeletal muscle tissues in “Exercise Science” were PPARGC1A, PPARD, MTOR, MAP1LC3A, MAP1LC3B, PRKAA1, AKT1, SLC2A4, MAPK1, COX4I1, MAPK14, MEF2A, MAPK8, RPS6KB1, and SOD1. Among them, PPARGC1A, AKT1, SLC2A4, MAPK1, and COX4I1 were specifically expressed in the skeletal muscle. However, expression of other genes was found to be significantly affected in other cell types of the skeletal muscle tissue.CONCLUSIONS: Genes such as PPARGC1A, which are specifically expressed in the skeletal muscle, may be analyzed without pretreating (such as perfusion) the skeletal muscle tissue. However, expression of other genes may depend on the skeletal muscle cell type. Thus, in such instances, pretreatment, such as perfusion and isolation, should be considered.

Next-Generation Ultrasol Curcumin Boosts Muscle Endurance and Reduces Muscle Damage in Treadmill-Exhausted Rats.

Curcumin positively affects performance during exercise and subsequent recovery. However, curcumin has limited bioavailability unless consumed in larger doses. In the current study, we examined the impact of a new formulation of curcumin, Next-Generation Ultrasol Curcumin (NGUC), which is relatively more bioavailable than natural curcumin on exhaustion time, grip strength, muscle damage parameters, and serum and muscle proteins. A total of 28 rats were randomly grouped as control (C, non-supplemented), exercise (E, non-supplemented), E+NGUC100 (supplemented with 100 mg/kg BW NGUC), and E+NGUC200 (supplemented with 200 mg/kg NGUC). Grip strength and exhaustion time were increased with NGUC supplementation (p < 0.0001). Creatine kinase (CK), lactate dehydrogenase (LDH), lactic acid (LA), myoglobin, malondialdehyde (MDA) concentrations were reduced in serum, and muscle tissue in NGUC supplemented groups (p < 0.05). In contrast, NGUC supplementation elevated the antioxidant enzyme levels compared to the non-supplemented exercise group (p < 0.01). Additionally, inflammatory cytokines were inhibited with NGUC administration (p < 0.05). NGUC decreased PGC-1α, p-4E-BP1, p-mTOR, MAFbx, and MuRF1 proteins in muscle tissue (p < 0.05). These results indicate that NGUC boosts exercise performance while reducing muscle damage by targeting antioxidant, anti-inflammatory, and muscle mass regulatory pathways.

Expression of different genotypes of bovine TRDMT1 gene and its polymorphisms association with body measures in Qinchuan cattle (Bos Taurus)

DNA methyltransferase 2 (DNMT2) was renamed as tRNA aspartic acid methyltransferase 1 (TRDMT1) by catalyzing the methylation of tRNAAsp anti-codon loop C38. The development of sequencing of nucleic acids and protein detection techniques have prompted the demonstration that TRDMT1 mediated tRNA modification affects protein synthesis efficiency. This process affects the growth and development of animals. The DNA of 224 Qinchuan cattles aged 2–4 years old was collected in this experiment. The genetic variations of TRDMT1 exon and some intron regions were detected by mixed pool sequencing technology. qRT-PCR and Western Blot were used to detect the expression levels of mRNA and protein produced with the combination of different genetic variant loci. Three haplotypes were detected and the distribution ratios were different. Muscle tissue mRNA and protein testing showed that there were differences in mRNA expression levels among different genotypes (P < 0.05) and the protein expression levels between different genotypes show the same trend as mRNA. This study provides potential molecular materials for the improvement of Qinchuan cattle reproductivity and provides theoretical support for studying the effects of livestock TRDMT1 on animal growth and development.

The Effect of Monsoon on Chemical Composition and Bioaccumulation of Heavy Metals in Scomberomorus commerson, Lacepede 1800, from Oman Sea

This study was performed to determine the chemical compositions and heavy metals in the muscle of Scomberomorus commerson from the Oman Sea, during the two seasons, pre-monsoon and post-monsoon in 2018. The protein, fat, moisture, and ash contents were determined by AOAC (Association of Official Analytical Chemists) methods. Heavy metal (Zn, Cu, and Pb) analyses were performed by atomic absorption spectrophotometer after acid digestion. There were significant differences between protein, fat, moisture, and ash values in muscle tissue in two seasons (P Cu>Pb. The amounts of Zn, Cu, and Pb were below maximum permissible limits (MPL) recommended by international standards (FAO, FAO/WHO, and MAFF). Results revealed that estimated daily and weekly intakes of Zn, Cu, and Pb were far below the permissible tolerable daily intake (PTWI) recommended by FAO/WHO. Therefore, consumption of S. commerson in the pre and post-monsoon has no risks for human health in the Oman Sea.

Adaptation of the two-dimensional electrophoresis method for canned meat

Studies of the qualitative indicators of canned meat in accordance with regulatory documents are carried out on average samples of specimens, but when studying by proteomic methods, such sampling does not allow high-quality separation of protein components due to the high fat content in the product. When two-dimensional electrophoresis was carried out on an average sample, fragments of the main muscle and connective tissue proteins of beef were found in small quantities, but the electrophoretogram was not very informative. A significantly better separation was achieved after removing the fat fraction from the product. When studying broth from canned meat, the largest amount of intensely coloured high-molecular-weight protein fractions with a mass of more than 50 kDa was revealed. The electrophoretogram of the meat pieces showed a wide range of proteins across the entire molecular weight range of the polyacrylamide gel, including major muscle proteins. The study of broth together with meat pieces but after fat removal is optimal for the primary screening of the protein component of canned meat.

ИССЛЕДОВАНИЕ ТЕХНОХИМИЧЕСКОЙ ХАРАКТЕРИСТИКИ ДАЛЬНЕВОСТОЧНОГО ШЛЕМОНОСЦА (GYMNOCANTHUS HERZENSTEINI)

The article considers the problem of the rational use of aquatic biological resources in the modern fishing process, which can be partially solved by the complex processing of hydrobionts, the by-catch being underutilized. Gobies or sculpins make about 22% of the by-catch in the catch of commercial fish species in the Far Eastern fishery basin. It is a promising fishing object, the biological value of which was studied earlier and proved in the recent studies. Despite the available reserves, gobies are not used for developing the food products or feed flour. The frequent reasons for low demand for products from such non-commercial raw materials can be: the lack of modern data on the chemical composition of the edible part, data on biological safety, methods of technological processing of raw materials and technology for obtaining food products. There are presented the study results on the size, mass and technological characteristics of Far Eastern stag-horn sculpin belonging to gobies Cottidae Gymnocanthus (Gymnocanthus Herzensteini). There is shown the relationship between the fish mass and the mass of muscle tissue, between the fish length and weight, and the fish weight and mass of the head. The yield of secondary raw materials (heads, entrails, bones, fins) has been determined. Based on the conducted chemical analysis, it was found out that Far Eastern staghorn sculpin belongs to the protein species of fish (19%) with a low lipid content (up to 2%). For the first time, the amino acid and fatty acid composition of proteins and lipids of fish muscle tissue has been investigated. It has been stated that the muscle tissue contains all essential amino acids, the rate of which is more than 100%. The objective indicators of the biological value of muscle tissue proteins were determined: the coefficients of difference between the amino acid rate, utility of amino acids, protein-water and lipid-protein coefficients were calculated. The content of macro- and micro-elements has been studied. It was inferred that the maximum permissible concentration of arsenic, cadmium, mercury and lead do not exceed the maximum permissible level.

JUSTIFICATION OF THE INNOVATIVE METHOD OF PRELIMINARY PROCESSING OF FISH RAW MATERIALS

The scientific article presents experimental data on the possibility of modification of the generally accepted traditional technology of pre-heat treatment of freshwater fish raw materials in the production of canned fish by developing an innovative method - dehydration with hydrochloric acid. Technological and rheological features of the muscle tissue of the object of study - silver carp, which is the most important object of aquaculture and commercial fish farming in Ukraine and in many other countries, require the use of pre-heat treatment. This technique is required to remove moisture from muscle tissue by denaturing sarcoplasmic proteins when the temperature rises above 95 C. Due to the high specific heat of fish muscle tissue, heat treatment is energy intensive and, consequently, not cost effective.&#x0D; In connection with the above promising direction of modification of preliminary heat treatment of raw materials of the fish industry in the production of canned fish should be the development and implementation of a new innovative energy-saving method of processing semi-finished products in the design of modern fish processing enterprises.&#x0D; The paper presents data on the effect of hydrochloric acid on the properties of muscle tissue of silver carp. This directional regulation of the moisture holding capacity in the direction of its reduction is possible by shifting the pH to the isoelectric point of muscle tissue proteins.&#x0D; The influence of such technological parameters as mass fraction of hydrochloric acid in the treatment solution, hydromodule (solution: raw material), temperature and duration of the process on the change of active acidity of muscle tissue of fish raw materials, and, accordingly, moisture binding capacity was established. Accordingly, the following technological parameters of the process were determined: mass fraction of hydrochloric acid - 0.1%, processing temperature 20–25°С, hydraulic module - 1:10, processing duration - 30 minutes. The introduction of the developed technological parameters of the innovative method of pre-treatment creates conditions in which the active acidity of muscle tissue is as close as possible to the isoelectric point of most fish proteins, which in turn provides minimum values of moisture binding capacity.&#x0D; Based on the obtained data, a technological method of pre-processing of fish raw materials in the production of canned fish has been developed, the use of which allows to completely eliminate energy-intensive thermal operation from the technological cycle, and accordingly significantly increase economic efficiency

The inducing of caspase and Bcl-2 pathway with royal jelly decreases the muscle tissue damage exposed with fluoride in rats.

In this study, 42 Wistar albino male rats (n = 42, 8 weeks old) were used. Rats were divided into 6 groups and 7 rats included each group. Groups: (i) Control group: Standard diet; (ii) RJ (royal jelly) group: Standard diet + royal jelly; (iii) F50 group: Standard diet + 50 mg/kg fluoride; (iv): F100 group: Standard diet + 100 mg/kg fluoride; (v) F50+RJ group: Standard diet + 50 mg/kg fluoride + royal jelly; (vi): F100+RJ group: Standard diet + 100 mg/kg fluoride + royal jelly. After 8 weeks, the rats were decapitated, and their muscle tissues were removed. Expression levels of Caspase-3, Caspase-6, Bax, tumor necrosis factor-α (TNF-α), interleukin 1 alpha (IL1-α) and Bcl-2 proteins in muscle tissue were determined by western blotting method. Histopathological analyses were also performed on the muscle tissue. Malondialdehyde (MDA), glutathione (GSH) and catalase (CAT) analyses were determined by a spectrophotometer. According to the obtained results, Bcl-2, TNF-α and IL1-α protein expression was increased in damage groups compared to the control and royal jelly groups, while Caspase-3, Caspase-6 and Bax protein expression levels decreased in damage groups. MDA level increased in damage groups compared to the control and royal jelly groups, while CAT and GSH levels increased with royal jelly application in royal jelly-given group in comparison to the flouride-exposed group. According to histopathological analysis results, edema and inflammatory cell formations were found in the injury groups, a tendency to decrease in these injuries was observed in the treatment groups. Based on these results, we can say that royal jelly has protective effects on muscle tissue against fluoride damage.Graphical abstract

Long-term ketamine administration induces bladder damage and upregulates autophagy-associated proteins in bladder smooth muscle tissue.

Long-term ketamine abuse can cause significant lower urinary tract symptoms in humans, termed ketamine-associated cystitis (KC). Here, we established a model of long-term (6 months) ketamine administration in wild-type (C57BL/6) mice. We elucidated the pathological effects of ketamine in the bladder and investigated changes in autophagy-associated protein expression (i.e., LC3, Beclin-1, and P62) and inflammatory cytokines (i.e., IL-6 and IL-1β) in the bladder smooth muscle tissue. Long-term ketamine administration reduced the number of layers in the bladder mucosal epithelial cells (4-5 layers in the saline group vs. 2-3 layers in the ketamine groups), but increased the number of mast cells and collagen fibers. LC3-II/LC3-I, Beclin-1, IL-6, and IL-1β protein expression in the bladder smooth muscle tissues of ketamine-treated mice was significantly increased. The mRNA and protein levels of P62 in the Ket-60 mg/kg group were also significantly increased, but not the Ket-30 mg/kg group. Our results reveal that long-term ketamine administration can cause cystitis-like pathological changes in mice, and the disordered autophagy in the bladder tissue may be involved in the persistent bladder damage following long-term administration of ketamine at 60 mg/kg.

Effect of metformin on the expression of SNAER proteins in the skeletal muscle of rats with type 2 diabetes

Background and Aims: SNARE proteins are composed of a combination of SNAP-23, Stx-4, and VAMP-2 isoforms that are significantly expressed in skeletal muscle. These proteins control the transport of GLUT4 to the cell membranes. The modifications in the expression of SNARE proteins can cause Type 2 diabetes. The present study aimed to assess the effect of metformin on the expression of these proteins in rats. Materials and Methods: For the purpose of the study, 40 male Wistar rats were randomly selected. Streptozotocin and Nicotinamide were used for the induction of type 2 diabetes. The animals were assigned to five groups (n=8), including healthy and diabetic groups as control, as well as three experimental groups which were treated with different doses of metformin (100, 150, and 200 mg/kg body weight) for 30 days. The quantitative reverse transcription PCR (RT-qPCR) method was applied to evaluate the expression of SNARE complex proteins.. Results: Based on the results, metformin (100, 150, and 200 mg/kg body weight) decreased serum glucose levels and increased serum insulin levels. This difference in dose of 200 mg/kg body weight was statistically significant (P&lt;0.05). Moreover, all three doses of metformin increased the expression of SNAP- 23, syntaxin-4, and VAMP-2 proteins in skeletal muscle tissue. Metformin at a dose of 200 mg/kg body weight demonstrated the most significant effects (P&lt;0.05). Conclusion: As evidenced by the results of the current study, another anti-diabetic mechanism of metformin is to increase the expression of SNARE proteins, which effectively improves insulin resistance and lowers blood glucose.

Investigation of Protein Biomarkers and Oxidative Stress in Pinirampus pirinampu Exposed to Mercury Species from the Madeira River, Amazon-Brazil.

In recent decades, the scientific community has widely debated the contamination of fish in the Amazon region by mercury species. As the diet of riverside populations in the Amazon region is based mainly on fish, these populations are exposed to mercurial species that can cause serious and irreversible damage to their health. The risks of consuming fish exposed to mercurial species in the Amazon region have motivated toxicological investigations. However, the effect of mercurial species on protein and enzyme levels is still controversial. In this work, analytical and bioanalytical techniques Two-dimensional polyacrylamide gel electrophoresis [2D-PAGE] Graphite Furnace Atomic Absorption Spectrometry [GFAAS], and Mass Spectrometry in Sequence with Electrospray Ionization [ESI-MS/MS] were used to identify proteins associated with mercury (metal-binding protein) in muscle and liver tissues of the fish species Pinirampus pirinampu from the Madeira River, in the Brazilian Amazon. Enzymatic and lipid peroxidation analyses were also used to assess changes related to oxidative stress. Determinations of total mercury by GFAAS indicated higher concentrations in liver tissue (555 ± 19.0µgkg-1) when compared to muscle tissue (60 ± 2.0µgkg-1). The fractionation process of tissue proteomes by 2D-PAGE and subsequent mapping of mercury by GFAAS in the protein spots of the gels identified the presence of mercury in three spots of the liver tissue (concentrations in the range of 0.800 to 1.90mgkg-1). The characterization of protein spots associated with mercury by ESI-MS/MS identified the enzymes triosephosphate isomerase A, adenylate kinase 2 mitochondrial, and glyceraldehyde-3-phosphate dehydrogenase as possible candidates for mercury exposure biomarkers. The muscle tissue did not show protein spots associated with mercury. Enzymatic activity decreased proportionally to the increase in mercury concentrations in the tissues.

Oxidative stress in broiler chicken and its consequences on meat quality

Oxidative stress is inevitable in poultry production, and it affects the physiological, behavioral and biochemical status of growing chicken which ultimately deteriorates meat quality. Appearance, texture, juiciness, tenderness and odor are responsible for the overall meat quality as they are essential perceptible features, which determine the consumer’s judgment. Overproduction of free radicals including reactive oxygen species (ROS) disturbs the mitochondrial function in living cells. During high-temperature mitochondrial substrate oxidation and electron transport chain (ETC) activity increases. This increased activity results in excessive production of superoxide that oxidizes protein and lipid contents in muscle tissues. By oxidizing protein and lipid, ROS spoils the nutritive quality of chicken meat. High ambient temperature is one of the major contributing factors that enhance oxidative stress. Poultry feed with anti-oxidant supplementation and innovative processing techniques can help the poultry industry to overcome oxidative stress.