Stimulation Of Metabolism Research Articles

Tumor Necrosis Factor α-Induced Protein 8-Like 2 Alleviates Nonalcoholic Fatty Liver Disease Through Suppressing Transforming Growth Factor Beta-Activated Kinase 1 Activation.

NAFLD prevalence has increased rapidly and become a major global health problem. Tumor necrosis factor α-induced protein 8-like 2 (TIPE2) plays a protective role in a cluster of liver diseases, such as autoimmune hepatitis, hepatitis B, and hepatocellular carcinoma. However, the function of TIPE2 in NAFLD remains unknown. Here, we investigated the role of TIPE2 in the development of NAFLD. Our study found that in vitro overexpression or knockout of TIPE2 significantly ameliorated or aggravated lipid accumulation and inflammation in hepatocytes exposed to metabolic stimulation, respectively. Consistently, in vivo hepatic steatosis, insulin resistance, inflammation, and fibrosis were alleviated in hepatic Tipe2-transgenic mice but exaggerated in hepatic Tipe2-knockout mice treated by metabolic challenges. RNA sequencing revealed that TIPE2 was significantly associated with the mitogen-activated protein kinase pathway. Mechanistic experiments demonstrated that TIPE2 bound with transforming growth factor beta-activated kinase 1 (TAK1), prevented tumor necrosis factor receptor-associated factor 6-mediated TAK1 ubiquitination and subsequently inhibited the TAK1 phosphorylation and activation of TAK1-c-Jun N-terminal kinase (JNK)/p38 signaling. Further investigation showed that blocking the activity of TAK1 reversed the worsening of hepatic metabolic disorders and inflammation in hepatic-specific Tipe2-knockout hepatocytes and mice treated with metabolic stimulation. TIPE2 suppresses NAFLD advancement by blocking TAK1-JNK/p38 pathway and is a promising target molecule for NAFLD therapy.

Mfn2 localization in the ER is necessary for its bioenergetic function and neuritic development

Mfn2 is a mitochondrial fusion protein with bioenergetic functions implicated in the pathophysiology of neuronal and metabolic disorders. Understanding the bioenergetic mechanism of Mfn2 may aid in designing therapeutic approaches for these disorders. Here we show using endoplasmic reticulum (ER) or mitochondria-targeted Mfn2 that Mfn2 stimulation of the mitochondrial metabolism requires its localization in the ER, which is independent of its fusion function. ER-located Mfn2 interacts with mitochondrial Mfn1/2 to tether the ER and mitochondria together, allowing Ca2+ transfer from the ER to mitochondria to enhance mitochondrial bioenergetics. The physiological relevance of these findings is shown during neurite outgrowth, when there is an increase in Mfn2-dependent ER-mitochondria contact that is necessary for correct neuronal arbor growth. Reduced neuritic growth in Mfn2 KO neurons is recovered by the expression of ER-targeted Mfn2 or an artificial ER-mitochondria tether, indicating that manipulation of ER-mitochondria contacts could be used to treat pathologic conditions involving Mfn2.

Effect of probiotic drug “Mucinolextra” on the physiological state of the body of young cattle

Relevance. The work is devoted to the assessment of the effectiveness of the feed additive “Mucinol-extra” together with chitosan, on the hematological and biochemical parameters of the blood of heifers of the black-and-white breed. The goal was to study the effect of the probiotic “Mucinol-extra” on the physiological state of the body of heifers. Experimental data showed that the content of total protein, albumins and globulins increased in both experimental groups. At the same time, the total protein index in the second group increased by 10.5%. The use of the probiotic preparation “Mucinol-extra” had a positive effect on the concentration of glucose in the blood of the experimental group. The content of erythrocytes in the blood of heifers in the experimental group was 12.23% higher than in the control group. Accordingly, the hemoglobin content in the experimental group exceeded the control significantly by 11.5%. The influence of the probiotic “Mucinol-extra”, together with chitosan, promoted the stimulation of protein metabolism, an increase in the level of redox processes and an improvement in the functional state of the body of young cattle. Methods. To study the effect of the probiotic “Mucinol-extra” on hematological parameters and biochemical parameters of blood serum, 2 groups of clinically healthy heifers of the black-and-white breed of 10 days of age were formed, selected according to a single physiological state, taking into account live weight, sex, age and clinical states. Each group consisted of 10 animals. Results. It was found that feeding the heifers of the experimental groups with the probiotic preparation “MUTSINOL”-extra had a favorable effect on the hematological and biochemical parameters of the blood.

Identification and characterization of MAM03055A: A novel bivalent sigma-2 receptor/TMEM97 ligand with cytotoxic activity

Sigma-2 receptor/transmembrane protein 97 (TMEM97) is upregulated in cancer cells compared to normal cells. Traditional sigma-2 receptor agonists induce apoptosis and autophagy, making them of interest in cancer therapy. Recently, we reported a novel metabolically stimulative function of the sigma-2 receptor, showing increased 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction and stimulation of glycolytic hallmarks. 6-Substituted analogs of the canonical sigma-2 receptor antagonist, 6-acetyl-3-(4-(4-(4-fluorophenyl)piperazin-1-yl)butyl)benzo[d]oxazol-2(3H)-one (SN79), produce both metabolically stimulative and cytotoxic effects. Here, we compare the activities of two related compounds: 6-amino-3-(4-(4-(4-fluorophenyl)piperazin-1-yl)butyl)benzo[d]oxazol-2(3H)-one (CM571), the 6-amino derivative of SN79, which binds with high affinity to both sigma-1 and sigma-2 receptors, and 1,3-bis(3-(4-(4-(4-fluorophenyl)piperazin-1-yl)butyl)-2-oxo-2,3-dihydrobenzo[d]oxazol-6-yl)thiourea (MAM03055A), a homo-bivalent dimer of CM571. MAM03055A resulted from the degradation of 3-(4-(4-(4-fluorophenyl)piperazin-1-yl)butyl)-6-isothiocyanatobenzo[d]oxazol-2(3H)-one (CM572), the cytotoxic 6-isothiocyanato SN79 derivative. MAM03055A exhibited high affinity and strong preference for sigma-2 receptors (sigma-1 Ki = 3371 nM; sigma-2 receptor Ki = 55.9 nM). Functionally, MAM03055A treatment potently induced cell death in SK-N-SH neuroblastoma, MDA-MB-231 breast, and both SW48 and SW480 colorectal cancer cell lines, causing proapoptotic BH3 interacting-domain death agonist (BID) cleavage in SK-N-SH cells. Conversely, CM571 induced metabolic stimulation. CM571 bound reversibly to both receptors, while MAM03055A bound pseudo-irreversibly to sigma-2 receptors and caused residual cytotoxic activity after acute exposure and removal of the compound from the media. Interestingly, MAM03055A induced a time-dependent loss of sigma-2 receptor/TMEM97 protein from cells, whereas monomer CM571 had no effect on receptor levels. These results suggest that monovalent and bivalent sigma-2 receptor ligands in this series interact differently with the receptor, thus resulting in divergent effects.

LANCL1 binds abscisic acid and stimulates glucose transport and mitochondrial respiration in muscle cells via the AMPK/PGC-1α/Sirt1 pathway

ObjectiveAbscisic acid (ABA) is a plant hormone also present and active in animals. In mammals, ABA regulates blood glucose levels by stimulating insulin-independent glucose uptake and metabolism in adipocytes and myocytes through its receptor LANCL2. The objective of this study was to investigate whether another member of the LANCL protein family, LANCL1, also behaves as an ABA receptor and, if so, which functional effects are mediated by LANCL1. MethodsABA binding to human recombinant LANCL1 was explored by equilibrium-binding experiments with [3H]ABA, circular dichroism, and surface plasmon resonance. Rat L6 myoblasts overexpressing either LANCL1 or LANCL2, or silenced for the expression of both proteins, were used to investigate the basal and ABA-stimulated transport of a fluorescent glucose analog (NBDG) and the signaling pathway downstream of the LANCL proteins using Western blot and qPCR analysis. Finally, glucose tolerance and sensitivity to ABA were compared in LANCL2−/− and wild-type (WT) siblings. ResultsHuman recombinant LANCL1 binds ABA with a Kd between 1 and 10 μM, depending on the assay (i.e., in a concentration range that lies between the low and high-affinity ABA binding sites of LANCL2). In L6 myoblasts, LANCL1 and LANCL2 similarly, i) stimulate both basal and ABA-triggered NBDG uptake (4-fold), ii) activate the transcription and protein expression of the glucose transporters GLUT4 and GLUT1 (4-6-fold) and the signaling proteins AMPK/PGC-1α/Sirt1 (2-fold), iii) stimulate mitochondrial respiration (5-fold) and the expression of the skeletal muscle (SM) uncoupling proteins sarcolipin (3-fold) and UCP3 (12-fold). LANCL2−/− mice have a reduced glucose tolerance compared to WT. They spontaneously overexpress LANCL1 in the SM and respond to chronic ABA treatment (1 μg/kg body weight/day) with an improved glycemia response to glucose load and an increased SM transcription of GLUT4 and GLUT1 (20-fold) of the AMPK/PGC-1α/Sirt1 pathway and sarcolipin, UCP3, and NAMPT (4- to 6-fold). ConclusionsLANCL1 behaves as an ABA receptor with a somewhat lower affinity for ABA than LANCL2 but with overlapping effector functions: stimulating glucose uptake and the expression of muscle glucose transporters and mitochondrial uncoupling and respiration via the AMPK/PGC-1α/Sirt1 pathway. Receptor redundancy may have been advantageous in animal evolution, given the role of the ABA/LANCL system in the insulin-independent stimulation of cell glucose uptake and energy metabolism.

The pyruvate kinase activator mitapivat reduces hemolysis and improves anemia in a β-thalassemia mouse model

Anemia in β-thalassemia is related to ineffective erythropoiesis and reduced red cell survival. Excess free heme and accumulation of unpaired α-globin chains impose substantial oxidative stress on β-thalassemic erythroblasts and erythrocytes, impacting cell metabolism. We hypothesized that increased pyruvate kinase activity induced by mitapivat (AG-348) in the Hbbth3/+ mouse model for β-thalassemia would reduce chronic hemolysis and ineffective erythropoiesis through stimulation of red cell glycolytic metabolism. Oral mitapivat administration ameliorated ineffective erythropoiesis and anemia in Hbbth3/+ mice. Increased ATP, reduced reactive oxygen species production, and reduced markers of mitochondrial dysfunction associated with improved mitochondrial clearance suggested enhanced metabolism following mitapivat administration in β-thalassemia. The amelioration of responsiveness to erythropoietin resulted in reduced soluble erythroferrone, increased liver Hamp expression, and diminished liver iron overload. Mitapivat reduced duodenal Dmt1 expression potentially by activating the pyruvate kinase M2-HIF2α axis, representing a mechanism additional to Hamp in controlling iron absorption and preventing β-thalassemia-related liver iron overload. In ex vivo studies on erythroid precursors from patients with β-thalassemia, mitapivat enhanced erythropoiesis, promoted erythroid maturation, and decreased apoptosis. Overall, pyruvate kinase activation as a treatment modality for β-thalassemia in preclinical model systems had multiple beneficial effects in the erythropoietic compartment and beyond, providing a strong scientific basis for further clinical trials.

Microbiome Catabolites as Novel Modulators of Cellular Glucose and Energy Metabolism

The gut microbiome supplies bioactive metabolites such as butyrate from dietary fiber to enhance the function of skeletal muscle mitochondria, and influences metabolism during exercise. Trained athletes have a distinctly different microbiome compared to sedentary individuals, since the composition and activity of the microbiota is in turn affected by muscle fitness. The gut microbiota regulate mitochondrial biogenesis through modulation of PGC-1α, SIRT1 and AMPK, and the mitochondria regulate the gut microbiota by modulating mucosal immune responses and intestinal barrier function. Skeletal muscle is the main site of postprandial glucose disposal; the glucose transporter GLUT4 is activated by insulin by translocation to the plasma membrane from internal vesicles. In diabetic and pre-diabetic insulin-resistant tissues, this GLUT4 translocation is compromised. Therapeutic strategies against insulin resistance, including exercise and diet-related interventions, aim to lower postprandial glycemia at least partly by restoring skeletal muscle glucose uptake and enhancing metabolism. Dietary phenolics can be considered as prebiotic-type molecules, including precursors present in the unbound form as well as covalently-attached to dietary fiber such as in cereal brans. After microbial action, many potentially bioactive phenolics are released and absorbed in the colon. These microbial products, once absorbed, interact with other tissues, including muscle and adipose cells, and stimulate the uptake of glucose by several mechanisms. For example, the microbial metabolite isovanillic acid sulfate (IVAS) stimulated a dose-dependent increase in glucose transport in human LHCN-M2 muscle cells through a GLUT4- and PI3K-dependent mechanism. IVAS also upregulated GLUT1, GLUT4 and PI3K p85α protein, and increased phosphorylation of Akt. The stimulation of glucose uptake and metabolism provides a novel link between the diet, gut microbiota and skeletal muscle energy utilization.

Specialized pro-resolving lipid mediators stimulate mitochondrial metabolism in macrophages

Abstract Chronic inflammation and sustained recruitment of classically activated macrophages (CAMs) with unchecked pro-inflammatory cytokine production is associated with disease development (e.g., atherosclerosis). Pro-inflammatory actions of CAMs are fueled by enhanced glycolysis and disruptions in the TCA cycle. Conversely, alternatively activated macrophages (AAMs) display an intact TCA cycle and mitochondrial oxidative phosphorylation (OXPHOS). Specialized pro-resolving lipid mediators (SPMs) stimulate resolution, in part, through actions on specific G-protein coupled receptors (GPCRs) in macrophages (e.g., RvD1□Fpr2). Whether SPMs exert pro-resolving effects by altering macrophage metabolism is unknown. We found that 1 hr treatment of SPMs (e.g., RvD1, RvD2, RvE1, and MaR1) enhanced basal (vehicle vs 1nM SPM; 6.11±0.1 vs RvD1 7.76±0.6 vs RvD2 9.48±0.9 vs RvE1 7.20±0.5 vs MaR1 8.73±0.9 pmol/min/μg protein; P<0.05; n=3), maximal (vehicle vs 0.1nM SPM; 9.06±1.1 vs RvD1 14.37±1.1 vs RvD2 16.54±2.7 vs RvE1 12.32±1.5 vs MaR1 13.28±1.3 pmol/min/μg protein; P<0.05; n=3), and ATP-linked respiration (vehicle vs 1nM SPM; 2.83±0.2 vs RvD1 4.50±0.3 vs RvD2 4.39±0.2 vs RvE1 4.71±0.3 vs MaR1 4.20±0.2 pmol/min/μg protein; P<0.05; n=3). Stimulation of mitochondrial metabolism with RvD1 was receptor mediated as Fpr2-deficient macrophages display no significant changes in metabolism following treatment (vehicle vs 1nM RvD1; basal 6.74±0.6 vs 6.52±0.2; maximal 11.54±1.2 vs 13.26±1.0; ATP-linked 5.84±0.8 vs 5.33±0.2 pmol/min/μg protein). Collectively, these data suggest that SPMs, despite having unique GPCRs, stimulate OXPHOS in macrophages, which could underlie their common pro-resolving properties.

Exaggerated exercise pressor reflex in a mouse model of femoral artery ligation

The exercise pressor reflex (EPR) is a reflexive mechanism in which blood pressure and heart rate increase in response to skeletal muscle contraction. These reflexive increases are caused by both mechanical and metabolic stimulation of group III and IV afferent neurons innervating in contracting skeletal muscle. Patients with peripheral artery disease (PAD) have an exaggerated EPR which contributes to exercise intolerance and morbidity and mortality. Previous studies in our laboratory have demonstrated that the EPR is overactive in a rat model of heart failure similar to it is in human heart failure patients. We determined that this abnormality was initiated by a blunting of the metabolic component but maintained by the mechanosensitive component of the reflex. Recently, we developed a mouse model of EPR, and have validated that the mouse model is similar to our rat model. In this model, studied the EPR in a model of peripheral artery disease (PAD). Our current results demonstrated that the blood pressure increase induced by passive stretch was exaggerated in mice 72 hours following femoral artery ligation. This exaggerated rise in blood pressure was not affected by SB-705498 (a TRPv1 receptor inhibitor) but it was nearly abolished by Gadolinium (a mechanical sensitive group III afferent neurons inhibitor) and it was partially reduced by GsMTx-4 (a selective inhibitor of the Piezo2 receptor). These results indicate that the exaggerated EPR in a murine model of PAD is mediated by mechanically sensitive group III neurons, which is mediated, in part, by Piezo2 receptors.

The effect of fish bone bioactive peptides on the wound healing process: an in vitro study on keratinocytes

Fish bones mainly contain type I collagen and hydroxyapatite, and despite of their potential for applications in biotechnology and biomedicine, they represent one of the major source of waste generated by fish processing industry. The present study was focused on the interaction of bioactive peptides extracted from silver carp (H. molitrix) bones with human keratinocytes in culture. The potential of fish bone bioactive peptides to influence cell viability, proliferation and migration was evaluated in different experimental models in vitro. The results demonstrated a high efficiency and bioactivity of the enzymatically extracted fish bone peptides in several processes involved in cutaneous wound healing, in particular stimulation of keratinocytes metabolism and migration. In conclusion, they present a huge potential for applications in skin tissue engineering, but also in the biomedical and cosmetic fields.

The role of mitophagy in the regulation of mitochondrial energetic status in neurons

ABSTRACT Mitochondria are the main cellular energy powerhouses and supply most of the energy in the form of ATP to fuel essential neuronal functions through oxidative phosphorylation (OXPHOS). In Alzheimer disease (AD), metabolic and mitochondrial disruptions are an early feature preceding any histopathological and clinical manifestations. Mitochondrial malfunction is also linked to synaptic defects in early AD. Mitophagy serves as a key cellular quality control mechanism involving sequestration of damaged mitochondria within autophagosomes and their subsequent degradation in lysosomes. However, it remains largely unknown whether mitophagy is involved in the regulation of energy metabolism in neurons, and if so, whether metabolic deficiency in AD is attributed to mitophagy dysfunction. Here we reveal that mitophagy is broadly activated in metabolically enhanced neurons upon OXPHOS stimulation, which sustains high energetic activity by increasing mitochondrial turnover and hence facilitating mitochondrial maintenance. Unexpectedly, in AD-related mutant HsAPP Tg mouse brains, early stimulation of OXPHOS activity fails to correct energy deficits but exacerbates synapse loss as a consequence of mitophagy failure. Excitingly, lysosomal enhancement in AD neurons restores impaired metabolic function by promoting elimination of damaged mitochondria, protecting against synaptic damage in AD mouse brains. Taken together, we propose a new mechanism by which mitophagy controls bioenergetic status in neurons, furthering our understanding of the direct impact of mitophagy defects on AD-linked metabolic deficits and shedding light on the development of novel therapeutic strategies to treat AD by the early stimulation of mitochondrial metabolism combined with elevation of lysosomal proteolytic activity. Abbreviations: AD: Alzheimer disease; Aβ: amyloid-β; APP: amyloid beta precursor protein; AV: autophagic vacuole; CHX: cycloheximide; CYCS: cytochrome c, somatic; DIV: days in vitro; FRET: Förster resonance energy transfer; Gln, glutamine; LAMP1: lysosomal associated membrane protein 1; LE: late endosome; Mito: mitochondria; Δψm: mitochondrial membrane potential; OCR: oxygen consumption rate; OXPHOS: oxidative phosphorylation; SQSTM1/p62: sequestosome 1; RHEB: Ras homolog, mTORC1 binding; ROS: reactive oxygen species; STX1: syntaxin 1; SYP: synaptophysin; Tg: transgenic; TMRE: tetramethylrhodamine ethyl ester; TEM: transmission electron microscopy; WT: wild type

Pre-storage chitosan-thyme oil coating control anthracnose in mango fruit

Anthracnose caused by Colletotrichum gloeosporioides is a severe postharvest mango disease. Postharvest application of fungicides is necessary to effectively control this disease, however, many of these fungicides are not allowed in many countries. In this study we aimed to investigate the combined effect of 1% chitosan plus 400 μLL−1 thyme oil to control anthracnose and improve shelf life of mango fruit (cv. White Chaunsa). We found that 400 μL L-1 thyme oil can completely inhibit in vitro mycelial growth of the fungus C. gloeosporioides. However, the combined application of 1% chitosan plus 400 μL L−1 thyme oil was more effective than thyme oil (400 μL L-1) alone in controlling the disease in artificially inoculated mango fruit. Furthermore, this combined treatment significantly (P ≤ 0.05) decreased naturally occurring decay. A mechanism related to promotion of fruit resistance by stimulation of phenolic metabolism is suggested by elevated phenylalanine ammonia-lyase (PAL) and peroxidase (POD) activities as compared to both the control and the synthetic fungicide Prochloraz. In addition, retention of physicochemical properties such as titratable acidity, total soluble solids, firmness, weight loss, color, and higher scores for sensory perception confirmed the efficacy of the treatment. This study demonstrated that the application of 1% chitosan plus 400 μL L-1 thyme oil more effectively controlled mango anthracnose as compared to synthetic fungicide; however, the commercial efficacy of the treatment needs to be tested.

Impact of PCSK9 on CTRP9-Induced Metabolic Effects in Adult Rat Cardiomyocytes.

The adipocytokine adiponectin and its structural homologs, the C1q/TNF-related proteins (CTRPs), increase insulin sensitivity, fatty acid oxidation and mitochondrial biogenesis. Adiponectin- and CTRP-induced signal transduction has been described to involve the adiponectin receptors and a number of co-receptors including the Low density lipoprotein receptor-related protein 1 (LRP1). LRP1 is another target of the proprotein convertase subtilisin/kexin-9 (PCSK9) in addition to the LDL-receptor (LDL-R). Here, we investigated the influence of PCSK9 on the metabolic effects of CTRP9, the CTRP with the highest homology to adiponectin. Knockdown of LRP1 in H9C2 cardiomyoblasts blunts the effects of CTRP9 on signal transduction and mitochondrial biogenesis, suggesting its involvement in CTRP9-induced cellular effects. Treatment of adult rat cardiomyocytes with recombinant PCSK9 but not knockdown of endogenous PCSK9 by siRNA results in a strong reduction in LRP1 protein expression and subsequently reduces the mitochondrial biogenic effect of CTRP9. PCSK9 treatment (24 h) blunts the effects of CTRP9-induced signaling cascade activation (AMP-dependent protein kinase, protein kinase B). In addition, the stimulating effects of CTRP9 on cardiomyocyte mitochondrial biogenesis and glucose metabolism (GLUT-4 translocation, glucose uptake) are largely blunted. Basal fatty acid (FA) uptake is strongly reduced by exogenous PCSK9, although protein expression of the PCSK9 target CD36, the key regulator of FA transport in cardiomyocytes, is not altered. In addition, only minor effects of PCSK9 were observed on CTRP9-induced FA uptake or the expression of genes involved in FA metabolism or uptake. Finally, this CTRP9-induced increase in CD36 expression occurs independent from LRP1 and LDL-R. In conclusion, PCSK9 treatment influences LRP1-mediated signaling pathways in cardiomyocytes. Thus, therapeutic PCSK9 inhibition may provide an additional benefit through stimulation of glucose metabolism and mitochondrial biogenesis in addition to the known lipid-lowering effects. This could be an important beneficial side effect in situations with impaired mitochondrial function and reduced metabolic flexibility thereby influencing cardiac function.

Vascular Type of Ehlers–Danlos Syndrome – a Rare Monogenic Connective Tissue Disease

The Ehlers-Danlos syndrome is a rare (orphan) disease characterized by the connective tissue dysplasia, fragility of the blood vessels and tissues, and variable clinical pattern. The vascular type of Ehlers-Danlos syndrome, which belongs to Group A according to the classification of 2017, is caused by the mutations in gene of alpha-1 chain of type III collagen COL3A1. The disease is characterized by the high mortality rate of the patients due to the spontaneous ruptures of the vascular walls and hollow viscera. The International Consortium (2017) developed the criteria for the clinical diagnosis of the vascular type of Ehlers – Danlos syndrome. The clinical case of the 16-year-old male patient with vascular type of Ehlers – Danlos syndrome is presented. The molecular genetic testing revealed in the child the previously described pathogenic mutation of splice site p.Gly798_Pro815del of COL3A1 gene associated with the severe course of the disease. In spite of the set of therapy measures aimed at the vascular reinforcement, stimulation and normalization of energy and mineral metabolism, the death occurred in 10 months due to the rupture of the aorta and renal artery. The Conclusion of the forensic medical examination is presented. The results of the care presented indicate that in order to avoid the omission of patients, it is advisable to revise the minimum set of signs required for the clinical diagnosis.

Pharmacological induction of mesenchymal-epithelial transition via inhibition of H2S biosynthesis and consequent suppression of ACLY activity in colon cancer cells

Hydrogen sulfide (H2S) is an important endogenous gaseous transmitter mediator, which regulates a variety of cellular functions in autocrine and paracrine manner. The enzymes responsible for the biological generation of H2S include cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST). Increased expression of these enzymes and overproduction of H2S has been implicated in essential processes of various cancer cells, including the stimulation of metabolism, maintenance of cell proliferation and cytoprotection. Cancer cell identity is characterized by so-called “transition states”. The progression from normal (epithelial) to transformed (mesenchymal) state is termed epithelial-to-mesenchymal transition (EMT) whereby epithelial cells lose their cell-to-cell adhesion capacity and gain mesenchymal characteristics. The transition process can also proceed in the opposite direction, and this process is termed mesenchymal-to-epithelial transition (MET). The current project was designed to determine whether inhibition of endogenous H2S production in colon cancer cells affects the EMT/MET balance in vitro. Inhibition of H2S biosynthesis in HCT116 human colon cancer cells was achieved either with aminooxyacetic acid (AOAA) or 2-[(4-hydroxy-6-methylpyrimidin-2-yl)sulfanyl]-1-(naphthalen-1-yl)ethan-1-one (HMPSNE). These inhibitors induced an upregulation of E-cadherin and Zonula occludens-1 (ZO-1) expression and downregulation of fibronectin expression, demonstrating that H2S biosynthesis inhibitors can produce a pharmacological induction of MET in colon cancer cells. These actions were functionally reflected in an inhibition of cell migration, as demonstrated in an in vitro “scratch wound” assay. The mechanisms involved in the action of endogenously produced H2S in cancer cells in promoting (or maintaining) EMT (or tonically inhibiting MET) relate, at least in part, in the induction of ATP citrate lyase (ACLY) protein expression, which occurs via upregulation of ACLY mRNA (via activation of the ACLY promoter). ACLY in turn, regulates the Wnt-β-catenin pathway, an essential regulator of the EMT/MET balance. Taken together, pharmacological inhibition of endogenous H2S biosynthesis in cancer cells induces MET. We hypothesize that this may contribute to anti-cancer / anti-metastatic effects of H2S biosynthesis inhibitors.

Experimental results on pancreatic juice parenteral application in broiler growing

The paper presents the results of the use of pancreatic enzymes in the form of intramuscular injection of pure pancreatic juice obtained from fistulated chickens to broiler chickens. At 7 days of age during the formation of groups, the differences between the control and experimental chickens were 17.9% (p<0.05) in favor of the former. It was found that after the injection of the drug 1 time in 7 days, there was a stimulation of metabolism in the experimental group broilers. By 14 days of age, the differences between the groups were 17.4% (p<0.05), to 21 days of age - 9.1% (p<0.05), to 28 days of age - 5.3%, to 35 - day-old age - 4.9%. Consequently, as the chickens were raised by 28 days of age, the chickens of the experimental group caught up with the live weight of the control ones, and, considering the increase in live weight, even exceeded this indicator (50.1 g/day versus 42.7). The use of parenteral pancreatic juice of chickens at a dose of 0.1ml/kg of live weight of broiler chickens allows to conclude that the drug has a stimulating effect on poultry metabolism, manifested by an increase in live weight gain, an increase in the content of lymphocytes, as an indicator of immunity, activation of protein and mineral metabolism in the body when using an enzyme preparation.

Features of protein metabolism in the body of broiler chickens when using the feed additive Peak-Antistress in the diet

Scientific publications describe the positive effect of feed additives and pharmacological complexes on metabolic processes in the body of broiler chickens, in particular, on the protein composition of the blood, meat productivity and protein accumulation in meat. The Peak-Antistress feed additive developed at the Department of Morphology, Physiology and Pharmacology of the South Ural State Agrarian University allows to reduce the technological load on the poultry body by stimulating the general metabolism and complex antioxidant action. Experiments on the use of the feed additive Peak-Antistress were carried out on broiler chickens of the final hybrid of the Arbor Acres cross in an industrial-type poultry farm with floor technology. The poultry was divided into three groups of 6,000 chickens each and kept in one workshop in separate sections. The control group received the main diet, the 1st experimental group received the main diet and feed additive at a dose of 1269 g / t of feed 5 days before slaughter, the 2nd experimental group received the main diet and feed additive at a dose of 1693 g / t of feed 5 days before slaughter. Slaughter of broiler chickens was carried out according to the technological instructions of the enterprise on the 38th day. Against the background of the use of the feed additive in the experimental groups of broiler chickens, stimulation of protein metabolism was observed, as evidenced by an increase in total protein in the blood by 7.9–20.1%, an increase in the level of protein in white meat by 0.1–0.3%, and a tendency to an increase in amino acids in white meat protein by 0.2–12.3%.

Sympathetic reactivity and inflammation: another joint problem in rheumatoid arthritis?

Sympathetic reactivity and inflammation: another joint problem in rheumatoid arthritis?

Streptomyces griseus: A new biocatalyst with N-oxygenase activity

Aromatic nitro compounds are key building blocks for many industrial syntheses and are also components of explosives, drugs and pesticides. Due to the environmentally unfriendly experimental conditions involved in their chemical syntheses, industrial processes would benefit from the use of biocatalysts. Among potentially useful enzymes, N-oxygenases, whose role is to oxygenate primary amines, are becoming relevant. These enzymes are involved in different secondary metabolic pathways in Streptomyces and in few other bacteria, forming part of the enzyme pools implicated in antibiotic synthesis. In this work, a group of Streptomyces strains, whose biomass was obtained from simple and novel culture media, were identified as new sources of N-oxygenase activity. Furthermore, the use of unspecific metabolic stimulation strategies allowed substantial improvements in the activity of whole cells as biocatalysts. It is remarkable the 6 to 50-fold increase in nitro compound yields compared to the biotransformation under standard conditions when Streptomyces griseus was the biocatalyst. In addition, biocatalyst substrate acceptance was studied in order to determine the biocatalytic potential of this enzyme.

In vivo O2 imaging in hepatic tissues by phosphorescence lifetime imaging microscopy using Ir(III) complexes as intracellular probes

Phosphorescence lifetime imaging microscopy (PLIM) combined with an oxygen (O2)-sensitive luminescent probe allows for high-resolution O2 imaging of living tissues. Herein, we present phosphorescent Ir(III) complexes, (btp)2Ir(acac-DM) (Ir-1) and (btp-OH)3Ir (Ir-2), as useful O2 probes for PLIM measurement. These small-molecule probes were efficiently taken up into cultured cells and accumulated in specific organelles. Their excellent cell-permeable properties allowed for efficient staining of three-dimensional cell spheroids, and thereby phosphorescence lifetime measurements enabled the evaluation of the O2 level and distribution in spheroids, including the detection of alterations in O2 levels by metabolic stimulation with an effector. We took PLIM images of hepatic tissues of living mice by intravenously administrating these probes. The PLIM images clearly visualized the O2 gradient in hepatic lobules with cellular-level resolution, and the O2 levels were derived based on calibration using cultured cells; the phosphorescence lifetime of Ir-1 gave reasonable O2 levels, whereas Ir-2 exhibited much lower O2 levels. Intravenous administration of NH4Cl to mice caused the hepatic tissues to experience hypoxia, presumably due to O2 consumption to produce ATP required for ammonia detoxification, suggesting that the metabolism of the probe molecule might affect liver O2 levels.