Catabolic Reactions Research Articles

Influence of Angiopoietin Treatment with Hypoxia and Normoxia on Human Intervertebral Disc Progenitor Cell’s Proliferation, Metabolic Activity, and Phenotype

Increasing evidence implicates intervertebral disc (IVD) degeneration as a major contributor to low back pain. In addition to a series of pathogenic processes, degenerated IVDs become vascularized in contrast to healthy IVDs. In this context, angiopoietin (Ang) plays a crucial role and is involved in cytokine recruitment, and anabolic and catabolic reactions within the extracellular matrix (ECM). Over the last decade, a progenitor cell population has been described in the nucleus pulposus (NP) of the IVD to be positive for the Tie2 marker (also known as Ang-1 receptor). In this study, we investigated the influence of Ang-1 and Ang-2 on human NP cell (Tie2+, Tie2− or mixed) populations isolated from trauma patients during 7 days in normoxia (21% O2) or hypoxia (≤5% O2). At the end of the process, the proliferation and metabolic activity of the NP cells were analyzed. Additionally, the relative gene expression of NP-related markers was evaluated. NP cells showed a higher proliferation depending on the Ang treatment. Moreover, the study revealed higher NP cell metabolism when cultured in hypoxia. Additionally, the relative gene expression followed, with an increase linked to the oxygen level and Ang concentration. Our study comparing different NP cell populations may be the start of new approaches for the treatment of IVD degeneration.

Fasting increases 18:2-containing phosphatidylcholines to complement the decrease in 22:6-containing phosphatidylcholines in mouse skeletal muscle

Fasting stimulates catabolic reactions in skeletal muscle to survive nutrient deprivation. Cellular phospholipids have large structural diversity due to various polar-heads and acyl-chains that affect many cellular functions. Skeletal muscle phospholipid profiles have been suggested to be associated with muscle adaptations to nutritional and environmental status. However, the effect of fasting on skeletal muscle phospholipid profiles remains unknown. Here, we analyzed phospholipids using liquid chromatography mass spectrometry. We determined that fasting resulted in a decrease in 22:6-containing phosphatidylcholines (PCs) (22:6-PCs) and an increase in 18:2-containing PCs (18:2-PCs). The fasting-induced increase in 18:2-PCs was sufficient to complement 22:6-PCs loss, resulting in the maintenance of the total amount of polyunsaturated fatty acid (PUFA)-containing PCs. Similar phospholipid alterations occurred in insulin-deficient mice, which indicate that these observed phospholipid perturbations were characteristic of catabolic skeletal muscle. In lysophosphatidic acid acyltransferase 3-knockout muscles that mostly lack 22:6-PCs, other PUFA-containing PCs, mainly 18:2-PCs, accumulated. This suggests a compensatory mechanism for skeletal muscles to maintain PUFA-containing PCs.

Correction of redox metabolism and the relationship of markers of systemic chronic inflammation with a measure of overall survival in cancer patients with multiorgan resections

Background. According to the literature, multiorgan resections are carried out with the most radical removal of healthy tissue. Therefore, there is a need for the most favorable preparation of the patient with perioperative therapy to reduce further complications with obtaining improved clinical and pathological prognostic indicators to increase the overall survival. Purpose: correction of redox metabolism based on the data of the oxidative modification of proteins, degree of their catabolic reaction, and data on the enzymatic state and lipid peroxidation in cancer patients with multiorgan resections on the gastrointestinal tract under conditions of perioperative intensive care. Materials and methods. The study involved 117 cancer patients aged 67.6 ± 3.7 years with locally advanced tumor processes of the gastrointestinal tract. Studies have been conducted on the enzymatic state, lipid peroxidation and oxidative modification of proteins, both in terms of the degree of fragmentation of their products in spontaneous and iron-induced reactions, and the level of medium-weight protein molecules. Serum levels of circulating tumor necrosis factor alpha, interleukin-6 and -8 were determined. Survival analysis was performed using the Kaplan-Meier method. Results. The study of patients has shown an improvement in the indicators of oxidative modification of proteins and lipid peroxidation. Survival in cancer patients with multiorgan resections demonstrated dependence on the levels of tumor necrosis factor alpha, interleukin-6 and -8 in the blood serum. Conclusions. Conducting perioperative intensive care makes it possible to reliably restore indicators of the enzymatic state, lipid peroxidation and oxidative protein modification products (on the fourth day and second week, p < 0.05). This gives us grounds for recommending the determination of these parameters in the group of cancer patients and the implementation of metabolic intensive care. In the group of L-ornithine L-aspartate and quercetin combination with povidone, the lowest indicators of systemic chronic inflammation and the best overall survival were found.

HEME Degradation Enzyme Biliverdin IXb Reductase Is Required for Stem Cell Glutamine Metabolism

Bioenergetic requirements of pluripotent stem cells (PSC) vary with lineage fate, and cellular adaptations rely largely on substrate availability and mitochondrial function to balance TCA-derived anabolic and redox-regulated antioxidant functions. Heme (protoporphyrin IX complexed with iron) serves as an indispensable co-factor for all aerobic cells, and its cytotoxicity is minimized by a two-step catabolic reaction that generates biliverdin (BV) and bilirubin (BR) tetrapyrroles, the penultimate step regulated by two non-redundant biliverdin reductases (IXa, BLVRA and IXb, BLVRB) retaining isomeric specificity and NAD(P)H-dependent redox coupling linked to BR antioxidant function. Thus, heme biosynthesis (initiated by the condensation of glycine and succinyl CoA) can be considered a linear pathway that utilizes cataplerotic TCA-derived carbon (derived from glucose and glutamine) linked to the heme degradation pathway and bilirubin excretion. Given the overlapping glucose/glutamine requirements in both heme synthesis and PSC bioenergetics, we studied consequences of dysregulated heme metabolism by targeted BLVRB disruption in iPSCs derived from human umbilical cord CD34+ hematopoietic cells. Compared to control iPSCs, BLVRB-deficient iPSCs had no reciprocal BLVRA induction, no alterations in heme oxygenase expression, and no differences in isomeric BV accumulation, although phenotypically defective in antioxidant handling with exaggerated apoptotic cell death. To better delineate metabolic pathway perturbations causally implicated in BLVRB- deficient antioxidant function and cell viability, we generated gene/metabolite clusters and an extended network plot formulated on RNASeq data coupled with liquid chromatography/mass spectrometric-based targeted metabolomics profiling of 290 intracellular metabolites. Metabolic enrichment with topological pathway analysis identified a limited number of defective pathways involving purine/pyrimidine nucleotide synthesis, redox homeostasis (pentose phosphate pathway, PPP) and TCA cycle intermediates (a-ketoglutarate, fumarate, and malate). Mitochondrial staining using TMRE as a functional and quantifiable marker of the mitochondrial transmembrane potential (DYm) identified no defect across the genotypes, although BLVRB -deficient iPSCs demonstrated defective basal and maximal oxygen consumption rates (OCR) restricted to glutamine (but not glucose) utilization. Metabolic flux quantification using [U6-13C] glucose revealed high-level and comparable (>97%) fractional labeling of 13C lactate across the genotypes, consistent with an active glycolytic metabolism that was comparable between control and BLVRB-/- iPSCs. In contrast, isotopic tracing using [U-13C5] glutamine demonstrated statistically-diminished glutamate-derived aKG accumulation (along with downstream TCA metabolites fumarate and malate isotopomers), results confirming rewired glutamine TCA entry, and reliance on glucose as a preferred substrate. Since the parallel PPP pathway utilizes glycolysis as the preferred substrate for generating both reducing equivalents (NADPH) and essential nucleotide component ribose-5-phosphate, we characterized three-dimensional embryoid body (EB) formation in the presence of the PPP pathway inhibitor 6-aminonicotinamide (6-AN), establishing statistically-decreased EB size (p<0.001) compared to control iPSCs. These data place heme catabolism in a crucial pathway of glutamine-regulated bioenergetic metabolism, and also suggest in principle that BLVRB inhibition represents an alternative strategy for modulating cellular glutamine utilization, a key substrate for cancer and hematopoietic metabolism. DisclosuresNo relevant conflicts of interest to declare.

Triacylglycerol remodeling in Physaria fendleri indicates oil accumulation is dynamic and not a metabolic endpoint.

Oilseed plants accumulate triacylglycerol (TAG) up to 80% of seed weight with the TAG fatty acid composition determining its nutritional value or use in the biofuel or chemical industries. Two major pathways for production of diacylglycerol (DAG), the immediate precursor to TAG, have been identified in plants: de novo DAG synthesis and conversion of the membrane lipid phosphatidylcholine (PC) to DAG, with each pathway producing distinct TAG compositions. However, neither pathway fits with previous biochemical and transcriptomic results from developing Physaria fendleri seeds for accumulation of TAG containing >60% lesquerolic acid (an unusual 20 carbon hydroxylated fatty acid), which accumulates at only the sn-1 and sn-3 positions of TAG. Isotopic tracing of developing P. fendleri seed lipid metabolism identified that PC-derived DAG is utilized to initially produce TAG with only one lesquerolic acid. Subsequently a nonhydroxylated fatty acid is removed from TAG (transiently reproducing DAG) and a second lesquerolic acid is incorporated. Thus, a dynamic TAG remodeling process involving anabolic and catabolic reactions controls the final TAG fatty acid composition. Reinterpretation of P. fendleri transcriptomic data identified potential genes involved in TAG remodeling that could provide a new approach for oilseed engineering by altering oil fatty acid composition after initial TAG synthesis; and the comparison of current results to that of related Brassicaceae species in the literature suggests the possibility of TAG remodeling involved in incorporation of very long-chain fatty acids into the TAG sn-1 position in various plants.

The Role of Plant-Based Protein Functional Food in Preventing Acute Respiratory Disease: A Case Study.

The Kaliningrad region is known for its specific climate, which can negatively affect the adaptive potential of the body. This manifests in an increased incidence of respiratory diseases and skin conditions. To prevent high morbidity, a plant protein product was included in the diet of first-year university students. This study aimed to assess the effectiveness of this food intervention in preventing the most common diseases among Kaliningrad students. Two groups of university students took part in the food trial. In the control group, catabolic processes prevailed in nutrient metabolism. Disadaptation manifested itself in the metabolism of proteins, vitamins, minerals, hematopoiesis and humoral immunity. Inflammation was indicated by α1- and α2-globulins, a weak immune response, and IgM and IgG. High oxidative stress and low antioxidative ability of blood serum were observed. The plant-based protein product (FP) helped preserve testosterone level and prevent an increase in catabolic reactions. Moreover, it had a positive effect on both red blood cell hematopoiesis (a smaller increase in the average volume of erythrocytes, the same average concentration and content of hemoglobin, an increased relative red cell distribution width (RDW) and white blood cell hematopoiesis (a beneficial effect for the immune system: lymphocytes, the relative content of neutrophils, monocytes, basophils and eosinophils). The stimulation of humoral immunity was evidenced by beta- and gamma-globulins, an active immune response, the level of IgM and IgG, antioxidant protection, reduction of peroxides and an increase in antioxidant activity of blood serum. The 34-week observation showed a 1.7-fold decrease in the incidence of respiratory illnesses and a 5.7-fold decrease in skin and subcutaneous tissue diseases. Acute respiratory infections were reduced 1.8-fold. There were no cases of community-acquired pneumonia in the treatment group, compared with 55.1‰ in the control group. The incidence of respiratory diseases was 3.3–10.6 times lower in the treatment group than in the control group in weeks 6–19. The findings testify to the prophylactic effect of functional food during social adaptation and acclimatization of students.

Harpic Induced Biochemical and Histological Changes in Fresh Water Fish Common Carp (Cyprinus Carpio L.)

Objectives: To investigate the xenobiotic action of toilet cleaner ‘Harpic’ on gills and muscles of fresh water teleost common carp (Cyprinus carpio L.). Methods: The test organism, fingerlings of Common carp (weight: 4.5±1.3g), (length: 5.3±1.5cm) were collected form Bhadra Reservoir Project, India. Static bioassay tests were conducted in order to evaluate the acute toxicity of Harpic. In all treatments, ten fully acclimatized test organisms were held and the same was observed for experiment and placed in different concentrations of Harpic to determine LC50 values after 24 hours. Behavioral responses and mortality of the fishes were recorded at the interval of 2 hours and the alternation of behavioral characteristics was recorded. Glucose was estimated by Anthrone method. Glycogen was estimated by Kemp’s method and Protein content was estimated by Lowery’s method. Findings: The glycogen muscle (0.015mg/g) and gills (0.06mg/g), and protein in muscles (0.482mg/g) and gills (0.749mg/g) levels were found to be depleted respectively in the tissues exposure to sub lethal concentration over the control. Whereas, the glucose level in the fish tissue showed an increase in muscle (0.168 mg/g) and in gills (0.108 mg/g) on pesticide exposure in comparison with the control. The depletion of glycogen level of gills (0.06mg/g) on pesticide exposure may be due to stress condition and increased metabolism. Further depletion of protein may also attribute to spontaneous utilization of amino acids in various catabolic reactions inside the organisms in order to combat the stress condition. Gill exhibited alteration such as showed desquamation of the epithelial lining, necrosis (Telangiectasia) of the secondary lamellae, shrinkage of secondary lamellae and also showed hypertrophy and hyperplasia at the base of the secondary lamellae. In case of muscle the nuclear proliferation was observed and also seen different size of the muscle fibres, disintegration of muscle bundles, atrophy of muscle bundles, marked thickening and separation of muscle bundles. Novelty: No such works carried out on the effect on younger developmental stages of fishes which are considered to be more susceptible and vulnerable to toxicants than those of adult stages. Keywords Cyprinus carpio, Harpic, Desquamation, Hyperglycaemia, Necrosis

Prooxidant and antioxidant systems’ indices as the markers of endogenous intoxication in ronchopathy and syndrome of obstructive sleep apnea in the dynamics of treatment

Introduction: Ronchopathy is a chronic progressive disease manifested by upper airway obstruction and chronic respiratory failure. The key process of pathological snoring is the obstructive breathing disorders. The obstructive sleep apnea syndrome (OSAS) develops on the basis of snoring. OSAS is accompanied by episodes of hypoxia and reoxygenation, which cause an increase of the level of reactive free radicals whith following development of the oxidative stress. The activation of peroxidative processes of proteins (POP) and lipids (POL) are initiated by free radicals which are noticeable components of endogenous intoxication (EI). The aim of the study was to investigate the intensity of POP and POL processes, the levels of OSAS components, and the indices EI in patients with ronchopathy and OSAS of varying severity in the dynamics of treatment. Materials and methods: 40 patients with ronchopathy and OSAS were examined at the State Institution “Institute of otolaryngology named after prof. O.S. Kolomiychenko of the National Academy of Medical Sciences of Ukraine”. All patients were divided according to the degree of snoring and hypoxia index (HI) into 4 groups of 10 persons each. Control group was formed by 10 healthy donors. The object of biochemical studies was blood serum. The intensity of POP was assessed by reaction with 2,4-dinitrophenyl-hydrazine by the Levin’s method in Reznick’s modification. POL intensity was determined by the interaction with 2-thiobarbituric acid (TBA) by Goncharenko. Catalase activity was determined by the method of Korolyuk and co-authors. The content of free thiol groups was determined by interaction with 5,5'-dithio-bis(2-nitrobenzoic acid). The content of medium weight molecules (MWM) and tyrosine-containing peptides (TCPs) were determined by spectroscopy at 254 and 280 nm, respectively. Statistical processing of the results was performed using the software package for biometric data WinPEPI. Results: Prior to the treatment in patients with ronchopathy and OSAS of varying severity, an increase in the content of MWM and TCPs were noted, that indicates the development of endogenous intoxication. In patients of all groups there was an intensification of POP, which was manifested by a significant increase of aDNFGn, aDNFGo, and kDNFGn levels. The content of TBA-positive products in patients with ronchopathy of both groups was at the level of control and increased significantly at progression of pathological process. In addition, in all groups of patients an increase of catalase activity was detected on the background of TCPs level decrease. It was found the efficacy of the offered treatment of patients with ronchopathy and OSAS of varying severity. The indices of EI, POP, POL, and antioxidant system’s were directed to improvement in contrast to the state before treatment, and some of them were improved almost to the level of control. Conclusions: It is established that the progression of hypoxia is accompanied by autointoxication, which is manifested by an increase in the content of MWM, as well as prove for the activation of catabolic reactions and excessive formation of cells’ breakdown products. It was also revealed by the intensification of POP and POL processes, the activation of which are associated with the development of insufficiency of enzymatic and nonenzymatic components of antioxidant system. The performed treatment can be considered as the effective one since on its completion all the studied indices were restored almost to the level of control.

Force Field Parameters for Fe2+4S2-4 Clusters of Dihydropyrimidine Dehydrogenase, the 5-Fluorouracil Cancer Drug Deactivation Protein: A Step towards In Silico Pharmacogenomics Studies.

The dimeric dihydropyrimidine dehydrogenase (DPD), metalloenzyme, an adjunct anti-cancer drug target, contains highly specialized 4 × Fe2+4S2−4 clusters per chain. These clusters facilitate the catalysis of the rate-limiting step in the pyrimidine degradation pathway through a harmonized electron transfer cascade that triggers a redox catabolic reaction. In the process, the bulk of the administered 5-fluorouracil (5-FU) cancer drug is inactivated, while a small proportion is activated to nucleic acid antimetabolites. The occurrence of missense mutations in DPD protein within the general population, including those of African descent, has adverse toxicity effects due to altered 5-FU metabolism. Thus, deciphering mutation effects on protein structure and function is vital, especially for precision medicine purposes. We previously proposed combining molecular dynamics (MD) and dynamic residue network (DRN) analysis to decipher the molecular mechanisms of missense mutations in other proteins. However, the presence of Fe2+4S2−4 clusters in DPD poses a challenge for such in silico studies. The existing AMBER force field parameters cannot accurately describe the Fe2+ center coordination exhibited by this enzyme. Therefore, this study aimed to derive AMBER force field parameters for DPD enzyme Fe2+ centers, using the original Seminario method and the collation features Visual Force Field Derivation Toolkit as a supportive approach. All-atom MD simulations were performed to validate the results. Both approaches generated similar force field parameters, which accurately described the human DPD protein Fe2+4S2−4 cluster architecture. This information is crucial and opens new avenues for in silico cancer pharmacogenomics and drug discovery related research on 5-FU drug efficacy and toxicity issues.

Metabolic flexibility via mitochondrial BCAA carrier SLC25A44 is required for optimal fever.

Importing necessary metabolites into the mitochondrial matrix is a crucial step of fuel choice during stress adaptation. Branched chain-amino acids (BCAAs) are essential amino acids needed for anabolic processes, but they are also imported into the mitochondria for catabolic reactions. What controls the distinct subcellular BCAA utilization during stress adaptation is insufficiently understood. The present study reports the role of SLC25A44, a recently identified mitochondrial BCAA carrier (MBC), in the regulation of mitochondrial BCAA catabolism and adaptive response to fever in rodents. We found that mitochondrial BCAA oxidation in brown adipose tissue (BAT) is significantly enhanced during fever in response to the pyrogenic mediator prostaglandin E2 (PGE2) and psychological stress in mice and rats. Genetic deletion of MBC in a BAT-specific manner blunts mitochondrial BCAA oxidation and non-shivering thermogenesis following intracerebroventricular PGE2 administration. At a cellular level, MBC is required for mitochondrial BCAA deamination as well as the synthesis of mitochondrial amino acids and TCA intermediates. Together, these results illuminate the role of MBC as a determinant of metabolic flexibility to mitochondrial BCAA catabolism and optimal febrile responses. This study also offers an opportunity to control fever by rewiring the subcellular BCAA fate.

Differential Metabolome in Rheumatoid Arthritis: a Brief Perspective.

Rheumatoid arthritis (RA) is a chronic autoimmune, inflammatory disease of the synovium that affects the movable joints. It develops due to the infiltration and invasion of the synovial joints by immune cells. Metabolism is anabolic or catabolic chemical reactions occurring in a cell. The biochemical pathways in synovial and immune cells are altered affecting the downstream metabolite formation. Changes in the metabolite levels alter signaling cascades which further intensify the disease. Despite current knowledge of metabolomics, there remain certain features that need to be elucidated to correlate the differential metabolite levels with RA. Metabolite profiling can be used to find altered patterns of metabolites in RA. Glucose, lipid, amino acid, and estrogen metabolism are the key pathways that are altered and contribute to the aggravation of RA. The altered metabolic pathways involved in different cells in RA results in complex interactions between metabolites and biomacromolecules; thus, it generates autoantigens. Moreover, understanding the correlation between differential metabolites and disease severity might help reveal potential new biomarkers and therapeutic targets for RA pathogenesis. So, considering the multi-faceted role of altered metabolites in the pathogenesis of RA, metabolic pathways of different cells are needed to be studied for a better understanding of their functions in the disease and thus, improving the present therapeutic strategies.

IDENTIFICATION OF C-TERMINALTELOPEPTIDES AS MARKERS OF CONNECTIVETISSUE DYSPLASIA IN BIOCHEMICAL BLOOD TESTS IN ADOLSCENTS WITH A HERNIATED DISC

Juvenile osteochondrosis, which can be complicated by a herniated disc, is a common disease in the pediatric population. Currently, this nosology is considered as one of the forms of manifestation of connective tissue dysplasia syndrome. A clinical study was conducted to identify dysplastic processes among 34 adolescents operated on for a herniated disc. Based on the characteristic phenotypic features, it was revealed that 15.36 % of the subjects had grade 1 connective tissue dysplasia, 74.47% — grade 2, and 10.17% — grade 3. The diagnosis was supplemented by a biochemical blood test for C-terminal telopeptides of type I collagen Beta-Cross Laps. In 18 patients (52,94%), the biochemical blood test exceeded the reference values, indicating consistency in the ongoing systemic catabolic reactions associated with the prevalent destruction of the collagen fibers of the tissues of the body.

БЕЛКИ КРОВИ И ИХ ИНФОРМАТИВНОСТЬ В ОЦЕНКЕ АДАПАТЦИОННЫХ РЕСУРСОВ КУР ПРИ ТЕХНОЛОГИЧЕСКОМ СТРЕССЕ

In the body of chickens, when exposed to the technological factor (the density of birds in the cage), a stress reaction developed as a result of activation of the hypathalamic-pituitary-adrenal system. The response and state of the neuroendocrine pathway is associated with the magnitude of the technological stress factor. When it is increased by 1.50 times, the maximum changes in the body of chickens are detected 4 hours after the start of the experiment. At the same time, the level of corticosterone and cortisol in the blood of birds increases by 3.42 and 2.99 times, increasing the rate of catabolic reactions in protein metabolism. Therefore, the amount of total protein in the blood-stream of chickens increases by 34.32 %, albumins by 26.74 %, urea and uric acid by 2.07 and 2.29 times, and the activity of AsAT and AlAT increases by 2.15 and 4.53 times (p&lt;0.05). The catabolic processes involve mainly blood albumins, whose nitrogen is used for the synthesis of uric acid. This is evidenced by a decrease in the value of Alb/uric acid by 42.74 % (p&lt;0.05). With an increase in the density of birds in the cage by 2 times, the reaction of the GGNS more pronounced and long-lasting. Although the maximum changes are registered 2 hours after the initiation of stress, they per-sist throughout the study period. At the same time, the level of corticosterone and cortisol in the blood of chickens increases by 4.17 and 3.67 times, the concentration of total protein by 39.44 %, both due to albumins (by 41.78 %) and globulins (by 37.82 %); the increase in the amount of urea and uric acid is 2.18 and 2.45 times. Both albumins and blood globulins are subjected to oxidative decomposition, which determines the decrease in the ratio TP/Urea, Alb/urea at, TP/uric acid and Alb/uric acid at 35.72-43.18 %. At the same time, the activity of AlAT increases by 7.56 times and AsAT by 2.21 times, determining the predominant use of carbon residues of free amino acids in the processes of gluconeogenesis (AlAT/AsAT increased by 3.75 times).

Myostatin inhibitor YK11 as a preventative health supplement for bacterial sepsis

Muscle wasting caused by catabolic reactions in skeletal muscle is commonly observed in patients with sepsis. Myostatin, a negative regulator of muscle mass, has been reported to be upregulated in diseases associated with muscle atrophy. However, the behavior of myostatin during sepsis is not well understood. Herein, we sought to investigate the expression and regulation of myostatin in skeletal muscle in mice inoculated with gram-negative bacteria. Interestingly, the protein level of myostatin was found to increase in the muscle of septic mice simultaneously with an increase in the levels of follistatin, NF-κΒ, myogenin, MyoD, p- FOXO3a, and p-Smad2. Furthermore, the inhibition of myostatin by YK11 repressed the levels of pro-inflammatory cytokines and organ damage markers in the bloodstream and in the major organs of mice, which originally increased in sepsis; thus, myostatin inhibition by YK11 decreased the mortality rate due to sepsis. The results of this study suggest that YK11 may help revert muscle wasting during sepsis and subdue the inflammatory environment, thereby highlighting its potential as a preventive agent for sepsis-related muscle wasting.

Sugar-mediated regulation and the role of HXK1, SnRK1, TOR kinases in &lt;i&gt;Arabidopsis thaliana&lt;/i&gt;

Sugars play an important role in plant metabolism. They are not only a source of energy, but also an integral part of the intracellular signalling network. Signals involving sugars regulate a variety of metabolic reactions, e.g. carbon and nitrogen metabolism, and produce plant response to biotic and abiotic stresses. This paper provides a brief review of modern publications about sugars acting as metabolites and signaling molecules. The well-known and recently discovered pathways for the transmission of sugar-mediated signals are described, along with their role in the regulation of plant metabolism and expression of nuclear genes. Hexokinase 1 (an enzyme for glucose synthesis), which was one of the first studied participants in the sugar-mediated signalling network, regulates the expression of many nuclear genes in response to changes in the glucose level. Hexokinase 1 should be considered as a broad-spectrum regulator due to its participation in the transmission of mitochondrial-nuclear signals and regulation of aging processes in plants, which functions lay beyond the regulation of metabolic reactions. Of particular interest is the participation of sugar-mediated signals in the switching of metabolic reactions in response to changes in carbohydrate concentrations. Sugar deficiency deactivates most energy-intensive processes, at the same time as stimulating photosynthesis or (in its absence) enhancing catabolic reactions due to activation of the SnRK1 kinase. Under sufficient sugar levels, the SnRK1 kinase is suppressed and the TOR kinase is activated, which stimulates anabolic reactions and growth. The role of competing SnRK1 and TOR kinases as the main regulators of such a process is considered, along with the function of signals mediated by trehalose-6-phosphate highly similar to the TOR signalling pathway. All these regulatory mechanisms enable plants to adapt to environmental changes and maintain homeostasis. It is possible that additional information will be obtained in the nearest future on the interaction of energy and stress-dependent signals in plants through the antagonism of TOR and SnRK1.

A comprehensive study on the effect of additives on the yield of LPC prepared from Medicago sativa Linn

During green crop fractionation, the leaf juice is released after pressing of macerated green foliage. The leaf juice expressed during this process is employed for the preparation of leaf protein concentrate (LPC), a protein-vitamin-mineral rich concentrate suitable for human nutrition. Singh (1962) recorded loss of proteins from the juice extracted from green foliage if it is not immediately processed for the preparation of LPC. It was pointed out that there is breakdown of proteins, appearance of ammonia, fermentative loss of sugars, drop in pH and decrease in the dry matter content when the juice is stored at room temperature for 48 hours. Proteolytic activity and microbial growth in juice deteriorate it. These catabolic reactions during storage of the juice results in low recovery of protein in the LPC with low yield of LPC per unit volume of the juice. It is therefore, suggested that the leaf juice should be employed for the preparation of LPC immediately after its extraction to achieve maximum yield of leaf protein. During present course of investigation effect of additives on the yield of LPC from lucerne juice stored for 48 hours was studied.

Macrophage Metabolic Signaling during Ischemic Injury and Cardiac Repair.

Macrophages are instrumental for the repair of organs that become injured due to ischemia, yet their potential for healing is sensitive to the availability of metabolites from the surrounding milieu. This sensitivity extends beyond anabolic and catabolic reactions, as metabolites are also leveraged to control production of secreted factors that direct intercellular crosstalk. In response to limiting extracellular oxygen, acute-phase macrophages activate hypoxia-inducible transcription factors that repurpose cellular metabolism. Subsequent repair-phase macrophages secrete cytokines to activate stromal cells, the latter which contribute to matrix deposition and scarring. As we now appreciate, these distinct functions are calibrated by directing flux of carbons and cofactors into specific metabolic shunts. This occurs through glycolysis, the pentose phosphate shunt, the tricarboxylic acid cycle, oxidative phosphorylation, nicotinamide adenine dinucleotides, lipids, amino acids, and through lesser understood pathways. The integration of metabolism with macrophage function is particularly important during injury to the ischemic heart, as glucose and lipid imbalance lead to inefficient repair and permanent loss of non-regenerative muscle. Here we review macrophage metabolic signaling under ischemic stress with implications for cardiac repair.

Estimation of metabolic fluxes distribution in Saccharomyces cerevisiae during the production of volatile compounds of Tequila.

A stoichiometric model for Saccharomyces cerevisiae is reconstructed to analyze the continuous fermentation process of agave juice in Tequila production. The metabolic model contains 94 metabolites and 117 biochemical reactions. From the above set of reactions, 93 of them are linked to internal biochemical reactions and 24 are related to transport fluxes between the medium and the cell. The central metabolism of S. cerevisiae includes the synthesis for 20 amino-acids, carbohydrates, lipids, DNA and RNA. Using flux balance analysis (FBA), different physiological states of S. cerevisiae are shown during the fermentative process; these states are compared with experimental data under different dilution rates (0.04-0.12 h$ ^{-1} $). Moreover, the model performs anabolic and catabolic biochemical reactions for the production of higher alcohols. The importance of the Saccharomyces cerevisiae genomic model in the area of alcoholic beverage fermentation is due to the fact that it allows to estimate the metabolic fluxes during the beverage fermentation process and a physiology state of the microorganism.

Prolonged preoperative fasting induces postoperative insulin resistance by ER-stress mediated Glut4 down-regulation in skeletal muscles.

Preoperative fasting aims to prevent pulmonary aspiration and improve bowel preparation, but it may induce profound systemic catabolic responses that lead to protein breakdown and insulin-resistant hyperglycemia after operation. However, the molecular mechanisms of catabolic reaction induced by prolonged preoperative fasting and surgical stress are undetermined. In this study, anesthetized rats were randomly assigned to receive a sham operation or laparotomy cecectomy. Fasting groups were restricted from food and water for 12 h before operation, while the feeding group had free access to food throughout the study period. Twenty-four hours after operation, the animals were sacrificed to collect blood samples and soleus muscles for analysis. Postoperative blood glucose level was significantly increased in the fasting group with elevated serum insulin and C-peptide. Continuous feeding reduced serum myoglobin and lactate dehydrogenase concentrations. Preoperative fasting activated inositol-requiring transmembrane kinase/endoribonuclease (IRE)-1α and c-Jun N-terminal kinase (JNK) mediated endoplasmic reticulum (ER)-stress, and reduced glucose transporter type 4 (Glut4) expression in the soleus muscle. Phospholamban phosphorylation was reduced and intracellular calcium levels were increased in the isolated skeletal muscle cells. Similar results were found in ER stress-induced C1C12 myoblasts. The expression of Glut4 was suppressed in the stressed C1C12, but was potentiated following inhibition of ER stress and chelation of intracellular free calcium. This study provides evidence demonstrating that prolonged preoperative fasting induces ER stress and generates insulin resistance in the skeletal muscle through suppression of Glut4 and inactivation of Ca2+-ATPase, leading to intracellular calcium homeostasis disruption and peripheral insulin resistance.

Persephonella atlantica sp. nov.: How to adapt to physico-chemical gradients in high temperature hydrothermal habitats

A novel thermophilic, microaerophilic and anaerobic, hydrogen- sulphur- and thiosulphate-oxidising bacterium, designated MO1340T, was isolated from a deep-sea hydrothermal chimney collected from the Lucky Strike hydrothermal vent field on the Mid-Atlantic Ridge. Cells were short, motile rods of 1.4–2.2μm length and 0.5–0.8μm width. Optimal growth was observed for a NaCl concentration of 2.5 % (w/v) at pH 6.5. As for other members of the genus Persephonella, strain MO1340T was strictly chemolithoautotrophic and could oxidise hydrogen, elemental sulphur or thiosulphate using oxygen as electron acceptor. Anaerobic nitrate reduction using hydrogen could also be performed. Each catabolic reaction had a different optimal growth temperature (65 to 75°C) and an optimal dissolved oxygen concentration (11.4 to 119.7 μM at 70°C for aerobic reactions) that varied according to the electron donors utilised. These experimental results are consistent with the distribution of these catabolic substrates along the temperature gradient observed in active hydrothermal systems. They strongly suggest that this adaptive strategy could confer a selective advantage for strain MO1340T in the dynamic part of the ecosystem where hot, reduced hydrothermal fluid mixes with cold, oxygenated seawater. Phylogenetic analysis indicated that strain MO1340T was a member of the genus Persephonella within the order Hydrogenothermales as it shared a 16S rRNA gene sequence similarity <95.5 % and ANI respectively 75.66 % with closest described Persephonella (P. hydrogeniphila 29WT). On the basis of the physiological and genomic properties of the new isolate, the name Persephonella atlantica sp. nov. is proposed. The type strain is MO1340T (=UBOCC-M-3359T =JCM 34026T).