Synthase Activity Levels Research Articles

IL-17A is involved in the hyperplasia of blood vessels in local lesions of psoriasis by inhibiting autophagy.

Increased angiogenesis is a pathological feature of psoriasis, but the pathomechanisms of angiogenesis in psoriasis are not clear. Interleukin-17A (IL-17A) is the major effect factor in the pathogenesis of psoriasis. Our results showed that IL-17A can promote angiogenesis and cause endothelial cell inflammation. Autophagy plays an important role not only in regulating inflammation, but also in regulating angiogenesis. Whether angiogenesis in psoriasis is related to autophagy remains unclear. In this study, we treated human umbilical vein endothelial cells (HUVECs) with IL-17A to simulate increased angiogenesis to study whether increased angiogenesis in psoriasis is related to autophagy. Our results showed that treatment of HUVECs with IL-17A significantly increased angiogenesis and expression levels of mRNA for multiple proinflammatory cytokines (CCL20, IL-8, CCL2, IL-6, and IL-1β) and, while decreasing intracellular levels of nitric oxide (NO) and NO synthase (NOS) activity. Moreover, IL-17A inhibited autophagy as shown that IL-17A significantly increased expression levels of LC3II and p62 proteins. Induction of autophagy ameliorated IL-17A-mediated inflammatory response and inhibited angiogenesis, accompanied by increased p-AMPKα(Thr172) and p-ULK1(Ser555) expression, and decreased p-mTOR(Ser2448) and p-ULK1(Ser757) expression. Furthermore, inhibition of either AMPK or lysosomal acidification completely overrode autophagy-induced changes in angiogenesis and NOS activity. Finally, induction of autophagy decreased apoptosis and caspase-3 activity in IL-17A-treated HUVECs. These results showed that IL-17A is involved in angiogenesis and inflammatory response by inhibiting autophagy through AMPK signaling pathway, suggesting that autophagy may be a new therapeutic target for psoriasis.

Epileptiform Discharges Reduce Neuronal ATP Production by Inhibiting F0F1-ATP Synthase Activity via A Zinc-α2-Glycoprotein-Dependent Mechanism.

Neuronal energy metabolism dysfunction, especially adenosine triphosphate (ATP) supply decrease, is observed in epilepsy and associated with epileptogenesis and prognosis. Zinc-α2-glycoprotein (ZAG) is known as an important modulator of energy metabolism and involved in neuronal glucose metabolism, fatty acid metabolism, and ketogenesis impairment in seizures, but its effect on neuronal ATP synthesis in seizures and the specific mechanism are unclear. In this study, we verified the localization of ZAG in primary cultured neuronal mitochondria by using double-labeling immunofluorescence, immune electron microscopy, and western blot. ZAG level in neuronal mitochondria was modulated by lentiviruses and detected by western blot. The F0F1-ATP synthase activity, ATP level, and acetyl-CoA level were measured. The binding between ZAG and F0F1-ATP synthase was determined by coimmunoprecipitation. We found that both ZAG and F0F1-ATP synthase existed in neuronal mitochondria, and there was mutual binding between them. Epileptiform discharge-induced decrease of mitochondrial ZAG level was reversed by ZAG overexpression. Epileptiform discharge or ZAG knockdown decreased F0F1-ATP synthase activity and ATP level in neurons, which were reversed by ZAG overexpression, while overexpression of ZAG along only increased F0F1-ATP synthase activity but not increased ATP level. Meanwhile, neither epileptiform discharges nor changes of ZAG level can alter the acetyl-CoA level. Moreover, epileptiform discharge did not alter F0F1-ATP synthase level. In conclusion, epileptiform discharge-induced ZAG decrease in neuronal mitochondria is correlated to F0F1-ATP synthase activity inhibition, which may possibly lead to ATP supply impairments. ZAG may be a potential therapeutic target for treating neuronal energy metabolism dysfunction in seizures with further researches.

Aerobic exercise training-induced alteration of gut microbiota composition affects endurance capacity.

This study aimed to clarify whether aerobic exercise training-induced alterations in the gut microbiota affect physiological adaptation with endurance exercise capacity. In study 1, ICR mice were randomly divided into three groups: vehicle intake + sedentary (V+S), vehicle intake + exercise training (V+Ex) and antibiotic intake + exercise training (AB+Ex). In the exercise training groups, treadmill running was performed for 8weeks. During the exercise training intervention, the antibiotic-intake group freely drank water containing antibiotics. In study 2, ICR mice were randomly divided into three groups: Sham, transplantation of caecum microbiota from sedentary mice (Sed-CMT) and exercise training mice (Ex-CMT). In study 1, the treadmill running time to exhaustion, an index of maximal aerobic capacity, after aerobic exercise training in the V+Ex group was significantly longer than that in the V+S and AB+Ex groups. Gastrocnemius muscle citrate synthase (CS) activity and PGC-1α protein levels in the V+Ex group were significantly higher than in the V+S and AB+Ex groups. The bacterial Erysipelotrichaceae and Alcaligenaceae families were positively correlated with treadmill running time to exhaustion. In study 2, the treadmill running time to exhaustion after transplantation was significantly higher in the Ex-CMT group than in the Sham and Sed-CMT groups. Furthermore, CS activity and PGC-1α protein levels in the gastrocnemius muscle were significantly higher in the Ex-CMT group than in the Sham and Sed-CMT groups. Thus, gut microbiota altered by aerobic exercise training may be involved in the augmentation of endurance capacity and muscle mitochondrial energy metabolism. KEY POINTS: Aerobic exercise training changes gut microbiota composition, and the Erysipelotrichaceae and Alcaligenaceae families were among the altered gut bacteria. The gut microbiota was associated with endurance performance and metabolic regulator levels in skeletal muscle after aerobic exercise training. Continuous antibiotic treatment attenuated the increase in endurance performance, citrate synthase activity and PGC-1α levels in skeletal muscle induced by aerobic exercise training. Gut microbiota transplantation from exercise-trained mice improved endurance performance and metabolic regulator levels in recipient skeletal muscle, despite the absence of aerobic exercise training.

Arginine metabolism governs microcycle conidiation by changing nitric oxide content in Metarhizium acridum.

Microcycle conidiation commonly exists in filamentous fungi and has great potential for mass production of mycoinsecticides. L-Arginine metabolism is essential for conidiation and conditional growth and virulence, but its role in microcycle conidiation has not been explored. Here, a unique putative arginase (MaAGA) was characterized in the entomopathogenic fungus Metarhizium acridum. Conidial germination and thermotolerance were facilitated by the disruption of MaAGA. Despite little impact on fungal growth and virulence, the disruption resulted in normal conidiation after a 60-h incubation on microcycle conidiation medium (SYA) under normal culture conditions. In the MaAGA-disruption mutant (ΔMaAGA), intracellular arginine accumulation was sharply increased. Replenishment of the direct metabolites of arginase, namely ornithine and/or urea, was unable to restore the disruption mutant's microcycle conidiation on SYA. Interestingly, nitric oxide synthase (NOS) activity and nitric oxide (NO) levels of the ΔMaAGA strain were markedly decreased in the 60-h-old SYA cultures. Finally, adding Nω-nitro-L-arginine, an inhibitor of NOS, into the SYA converted the microcycle conidiation of the wild-type strain to normal conidiation. In contrast, adding sodium nitroprusside, an NO donor, into the SYA recovered the mutant's microcycle conidiation. The results indicate that arginine metabolism controls microcycle conidiation by changing the content of NO. KEY POINTS: • The MaAGA-disruption led to normal conidiation on microcycle conidiation medium SYA. • Nitric oxide (NO) level of the ΔMaAGA strain was markedly decreased. • Adding an NO donor into the SYA recovered the microcycle conidiation of ΔMaAGA.

Proanthocyanidin delays litchi peel browning by inhibiting ethylene biosynthesis, respiratory metabolism, and phenol oxidase activities

Proanthocyanidin (PA) promotes antioxidant capacity and enhances resistance against oxidative stress-induced senescence in fruits after harvest. However, the effects of PA on the postharvest physiology of litchi fruit remain unclear. This study aimed to determine the effect of PA on ethylene and respiration physiology, and on browning enzymes of ‘feizixiao’ litchi stored at 25 °C for 8 d. Proanthocyanidin treatment delayed peel browning and color change, maintained higher peel lightness, and reduced ethylene production and respiration rates in litchi fruit. Subsequently, the key genes and/or enzymes involved in the ethylene biosynthesis pathway and respiration metabolism were determined. The PA-treated fruit exhibited lower levels of 1-aminocyclopropanecarboxylic acid (ACC) content, ACC synthase (ACS) and ACC oxidase (ACO) activity, and an inhibition of LcACS7/9 and LcACO1/2 genes on the peel and pulp compared to that of the control. In addition, the application of PA reduced respiration rate by downregulating the expression of LcAtpB, LcAOX1, LcUCP1, LcAAC1, and LcSnRK2. Furthermore, the phenol oxidase including peroxidase (POD), polyphenol oxidase (PPO), and laccase (LAC), were inhibited during litchi peel browning and senescence. Therefore, the process of PA-delayed browning of litchi may occur by delaying ethylene production and respiratory rate and inhibiting phenol oxidase activities in litchi fruit.

Artemisinin and Its Derivate Alleviate Pulmonary Hypertension and Vasoconstriction in Rodent Models.

Background Pulmonary arterial hypertension (PAH) is a complex pulmonary vasculature disease characterized by progressive obliteration of small pulmonary arteries and persistent increase in pulmonary vascular resistance, resulting in right heart failure and death if left untreated. Artemisinin (ARS) and its derivatives, which are common antimalarial drugs, have been found to possess a broad range of biological effects. Here, we sought to determine the therapeutic benefit and mechanism of ARS and its derivatives treatment in experimental pulmonary hypertension (PH) models. Methods Isolated perfused/ventilated lung and isometric tension measurements in arteries were performed to test pulmonary vasoconstriction and relaxation. Monocrotaline (MCT) and hypoxia+Su5416 (SuHx) were administered to rats to induce severe PH. Evaluation methods of ARS treatment and its derivatives in animal models include echocardiography, hemodynamics measurement, and histological staining. In vitro, the effect of these drugs on proliferation, viability, and hypoxia-inducible factor 1α (HIF1α) was examined in human pulmonary arterial smooth muscle cells (hPASMCs). Results ARS treatment attenuated pulmonary vasoconstriction induced by high K+ solution or alveolar hypoxia, decreased pulmonary artery (PA) basal vascular tension, improved acetylcholine- (ACh-) induced endothelial-dependent relaxation, increased endothelial nitric oxide (NO) synthase (eNOS) activity and NO levels, and decreased levels of NAD(P)H oxidase subunits (NOX2 and NOX4) expression, NAD(P)H oxidase activity, and reactive oxygen species (ROS) levels of pulmonary arteries (PAs) in MCT-PH rats. NOS inhibitor, L-NAME, abrogated the effects of ARS on PA constriction and relaxation. Furthermore, chronic application of both ARS and its derivative dihydroartemisinin (DHA) attenuated right ventricular systolic pressure (RVSP), Fulton index (right ventricular hypertrophy), and vascular remodeling of PAs in the two rat PH models. In addition, DHA inhibited proliferation and migration of hypoxia-induced PASMCs. Conclusions In conclusion, these results indicate that treatment with ARS or DHA can inhibit PA vasoconstriction, PASMC proliferation and migration, and vascular remodeling, as well as improve PA endothelium-dependent relaxation, and eventually attenuate the development and progression of PH. These effects might be achieved by decreasing NAD(P)H oxidase generated ROS production and increasing eNOS activation to release NO in PAs. ARS and its derivatives might have the potential to be novel drugs for the treatment of PH.

Transcriptional Analyses of Genes Related to Fodder Qualities in Giant Leucaena Under Different Stress Environments.

Leucaena leucocephala subsp. glabrata (giant leucaena) is a tree legume, whose foliage is used as a fodder for animals because of its high protein content. In spite of being a highly nutritious fodder, giant leucaena foliage has two undesirable secondary metabolites, mimosine and tannin. The amounts of mimosine and tannin in giant leucaena foliage are known to vary under different environmental conditions. Giant leucaena was grown under different salinity, pH and nitrogen availability conditions. It produced the highest amounts of mimosine at pH 6.0–7.0, whereas, variation in soil pH did not affect tannin concentrations. Salinity stress had negative effects on both mimosine and tannin concentrations, while nitrogen abundance promoted both mimosine and tannin production. Seven genes for mimosine and tannin metabolism were isolated from a transcriptome library of giant leucaena. These were mimosine synthase, mimosinase, chalcone synthase, flavanone 3β-hydroxylase, dihydroflavonol reductase, leucoanthocyanidin reductase, and anthocyanidin reductase. The highest level of mimosine synthase activity was observed in the absence of salt in the soils. Mimosine synthase activities had strong positive correlation with mimosine concentrations in the foliage (R2 = 0.78) whereas mimosinase expression did not appear to have a direct relationship with salt concentrations. The expression of mimosine synthase was significantly higher in the leucaena foliage under nitrogen abundant condition than in nitrogen deficiency conditions, while mimosinase expression was significantly higher under nitrogen deficiency condition than in nitrogen abundance conditions. Mimosine concentrations in the foliage were positively correlated with the expression levels of mimosine synthase but not mimosinase. Similarly, the concentrations of tannin were positively correlated with expression levels of dihydroflavonol reductase, leucoanthocyanidin reductase, and anthocyanidin reductase. Understanding of the environmental conditions that promote or inhibit transcription of the genes for mimosine and tannin biosynthesis should help to design environmental conditions that inhibit transcription of these genes, resulting in reduced levels of these compounds in the leucaena foliage.

Azotobacter chroococcum and Pseudomonas putida enhance pyrroloquinazoline alkaloids accumulation in Adhatoda vasica hairy roots by biotization

Adhatoda vasica is used in the treatment of cold, cough, chronic bronchitis, asthma, diarrhea, and dysentery. The biological activities of this species are attributed with the presence of alkaloids, triterpenoids, and flavonoids. Agrobacterium rhizogenes-mediated transformation of A. vasica, produces pyrroloquinazoline alkaloids, was achieved by infecting leaf discs with strain ATCC15834. The bacterial strain infected 82.7% leaf discs and 5–7 hairy root initials were developed from the cut edges of leaf discs. In this study, seven strains of Azotobacter chroococcum and five strains of Pseudomonas putida were used for the biotization of hairy roots. Plant growth-promoting rhizobacteria (PGPR) develops symbiotic association with roots of plants and increases the growth parameters of plants. PGPR (A. chroococcum and P. putida) increased the profiles of nitrogenase and acid phosphatase enzymes, biomass, dry matter contents, anthranilate synthase activity and accumulation of pyrroloquizoline alkaloids in the biotized hairy roots. Both enzymes (nitrogenase and acid phosphatase) maintain sufficient supply of nitrogen and dissolved phosphorus to the cells of hairy roots therefore, the levels of anthranilate synthase activity and pyrroloquinazoline alkaloids are increased. Total seven pyrroloquinazoline alkaloids (vasicine, vasicinone, vasicine acetate, 2-acetyl benzyl amine, vasicinolone, deoxyvasicine and vasicol) were identified from the biotized hairy roots of A. vasica. In our study, biotization increased the profiles of pyrroloquinazoline alkaloids therefore, this strategy may be used in increasing the production of medicinally important secondary metabolites in other plant species also. Our hypothetical model demonstrates that P. putida cell surface receptors receive root exudates by attaching on hairy roots. After attachment, the bacterial strain penetrates in the biotized hairy roots. This endophytic interaction stimulates acid phosphatase activity in the cells of biotized hairy roots. The P. putida plasmid gene (ppp1) expression led to the synthesis of acid phosphatase in cytosol. The enzyme enhances phosphorus availability as well as induces the formation of phosphoribosyl diphosphate. Later, phosphoribosyl diphosphate metabolizes to tryptophan and finally tryptophan converts to anthranilic acid. The synthesized anthranilic acid used in the synthesis of alkaloids in A. vasica.

Neurological restorative effects of the flavanol (‐)‐epicatechin in a rodent model of Gulf War Illness

Gulf War Illness (GWI) afflicts ~30% of the US military personnel who served in the 1990‐91 Persian Gulf War. Symptoms include cognitive deficits, muscle pain, weakness, exercise intolerance and fatigue which are still present after 30 years in war Veterans. Suspect causal agents include exposure to the compounds pyridostigmine (PB), permetrim (PM) and N,N‐diethyl‐m‐toluamide (DEET) which were used as protectants against nerve gases (PB) and insects. We previously reported a study to model GWI in which young male rats were provided PB, PM and DEET at equivalent human doses and physical restraint (to induce stress) for 3 weeks. In GWI animals, skeletal muscle weight was 35% lower vs. controls, which correlated with decreases in myofiber area, limb strength and treadmill time/distance. In a follow up study, we reported on the beneficial effects of the cacao flavanol (‐)‐epicatechin (epi) provided for 2 weeks by oral gavage on skeletal muscle atrophy and loss of function. In the current study, we wished to explore the potential of Epi to beneficially impact neurological measures of memory including multiple markers of hippocampus structure and function. Male Wistar rats underwent 3 weeks of exposure to either vehicles or DEET, PM, PB and stress. Subgroups of GWI rats (n=7/subgroup) received 15 days of either water (vehicle) or 1 mg/kg/day of Epi treatment by oral gavage and were compared to normal control (n=7). Object recognition tasks were performed to assess effects on memory and hippocampus samples were collected for histological and biochemical analysis. Results demonstrate that Epi treatment yields significant improvements in short and long‐term memory vs. GWI rats yielding values similar to those of controls. The assessment of hippocampus oxidative stress (protein carbonylation) and pro‐inflammatory cytokines levels (ELISA) of IL‐1β, TNF‐α and IFN‐γ (figure) yielded significant increases with GWI that were fully normalized with Epi to become comparable to controls. Significant increases in markers of hippocampus neuroinflammation (Iba1 and GFAP) and cell death (caspase activity) were noted with GWI and were significantly reduced with Epi. The neuronal survival signaling pathways (TREM2, PI3K and AKT) were adversely impacted by GWI and were partially or fully restored by Epi. Multiple markers of mitochondrial function (citrate synthase activity and ATP levels) adversely impacted by GWI and were fully restored by Epi. Thus, in an animal model of GWI, Epi beneficially impacted markers of hippocampus neuroinflammation, oxidative stress, cell survival, neurotoxicity and mitochondrial function. Such effects translated into improvements in functional endpoints associated with memory centers. As per the recognized safety profile of Epi clinical studies are warranted to explore the effects of treatment in Gulf War Veterans.

Characterization of Source–Sink Traits and Carbon Translocation in Maize Hybrids under High Plant Density

Both compact planting and selecting superior maize (Zea mays L.) hybrids can greatly optimize the source–sink relationship and enhance maize productivity. However, the underlying physiological mechanism for regulating carbon (C) assimilate transport and influencing grain yield between maize cultivars has remained unclear under contrasting plant densities. A two-year field experiment was conducted to investigate grain yield, vascular bundle character, grain filling, C allocation in grains and other tissues, and hormone level and enzyme activity in grains under 60,000 (ND) and 90,000 plants ha−1 (HD) densities using Xianyu 335 (XY335) and Zhengdan958 (ZD958) hybrids. Compared to the ZD958, XY335 increased grain yield, kernel number per plant (KNP), and sink capacity by 11.4%, 15.7%, and 7.4%, respectively. Moreover, XY335 performed higher net photosynthetic rate and sucrose synthase activities in grains than those in ZD958, and higher levels of sucrose phosphate synthase and soluble acid invertase activity were mainly exhibited in the middle of the grain filling stage, which contributed to increasing the proportion of grain in total dry matter, grain C content and leaf C transport efficiency by 4.3%, 12.2%, and 52.9%, respectively, under HD conditions. Additionally, a greater area and number of small vascular bundle in ear of XY335 resulted in 21.3% higher matter transport efficiency and 4.8% higher maximum grain filling rate than ZD958 under HD conditions. In addition, grains of XY335 exhibited generally higher levels of indole acetic acid (IAA) and abscisic acid (ABA), as well as ABA/GA3 ratio after maize pollination relative to those from ZD958, conducive to regulating C translocation from leaves to grains. Overall, our study illustrates that stronger source activity, sink characteristics, and matter transport channels for maize hybrids are significant for C assimilate transport to grain for achieving high grain yield under higher plant density.

The mesoionic compound MI-D changes energy metabolism and induces apoptosis in T98G glioma cells

The mesoionic compound 4-phenyl-5-(4-nitro-cinnamoyl)-1,3,4-thiadiazolium-2-phenylamine chloride (MI-D) impairs mitochondrial oxidative phosphorylation and has a significant antitumour effect against hepatocarcinoma and melanoma. This study evaluated the cytotoxic effect of MI-D on T98G glioblastoma cells and investigated whether the impairment of oxidative phosphorylation promoted by MI-D is relevant to its cytotoxic effect. The effects of MI-D on T98G cells cultured in high glucose Dulbecco's modified Eagle's medium (DMEM) HG (glycolysis-dependent) and galactose plus glutamine-supplemented Dulbecco's modified Eagle's medium (DMEM) GAL (oxidative phosphorylation-dependent) were compared. T98G cells grown in DMEM GAL medium exhibited higher respiration rates and citrate synthase activity and lower lactate levels, confirming the metabolic shift to oxidative phosphorylation in these cells. MI-D significantly decreased the cell viability in a dose-dependent manner in both media; however, T98G cells cultured in DMEM GAL medium were more susceptible. The mesoionic significantly inhibited mitochondrial oxidative phosphorylation of glioma cells in both media. At the same time, lactate levels were not altered, indicating an absence of compensatory glycolysis activation. Additionally, MI-D increased the citrate synthase activity of cells in both media, which in DMEM HG-cultivated cells was followed by citrate accumulation. Apoptosis dependent on caspase-3 mediated the toxicity of MI-D on T98G cells. The higher susceptibility of glioma cells cultured in DMEM GAL medium to MI-D indicates that the impairment of mitochondrial functions is involved in mesoionic cytotoxicity. The results of this study indicate the potential use of MI-D for glioblastoma treatment.

Impact of ATP synthase/coupling factor 6 in hypoxic pulmonary arterial hypertension: An experimental rat model.

Hypoxia-induced pulmonary arterial hypertension (PAH) is characterized by prostacyclin (PGI2 ) disorder, which manifests in the same manner as in monocrotaline (MCT)-induced PAH. Endogenous PGI2 inhibitor coupling factor 6 (CF6) is involved in MCT-induced PAH. This study aimed to explore the presence or absence of a correlation between hypoxia-induced PAH and CF6. This study was conducted between January 2019 and June 2020. A total of 135 male Wistar rats (aged 8 weeks and weighing 200-250 g) were randomly divided into five groups: (A) control, (B) 1 week of hypoxia, (C) 2 weeks of hypoxia, (D) 3 weeks of hypoxia, and (E) 4 weeks of hypoxia. CF6 expression in both lung tissue and blood samples from the lung vasculature and tail vein was measured by western blotting, immunohistochemistry, reverse transcription polymerase chain reaction, and enzyme-linked immunosorbent assay. Hemodynamic and morphological changes in hypoxia-induced rats indicated PAH development. The results showed the presence of a correlation between the mRNA and protein levels of CF6 in lung tissue, activity of mitochondrial ATP synthase, and hypoxia time, and there was a significant increment in the group exposed to hypoxia for 4 weeks compared to the control group. The decrement expression of ATPase inhibitory factor 1 (IF 1) mRNA was consistent with the outcomes of ATP synthase activity in lung tissue in the 4 weeks of hypoxia group compared with the control group. However, the levels of CF6 and ATP synthase activity did not differ between blood samples from the lung vasculature and tail vein. : In hypoxia-induced PAH, CF6 showed downregulated expression in lung tissue, but not in pulmonary vasculature and circulation. Therefore, we speculated that CF6 and ATP synthase may play important roles in hypoxia-induced PAH.

Frequent Manipulation of Resistance Training Variables Promotes Myofibrillar Spacing Changes in Resistance-Trained Individuals.

We sought to determine if manipulating resistance training (RT) variables differentially altered the expression of select sarcoplasmic and myofibril proteins as well as myofibrillar spacing in myofibers. Resistance-trained men (n = 20; 26 ± 3 years old) trained for 8 weeks where a randomized leg performed either a standard (CON) or variable RT protocol (VAR: manipulation of load, volume, muscle action, and rest intervals at each RT session). A pre-training (PRE) vastus lateralis biopsy was obtained from a randomized single leg, and biopsies were obtained from both legs 96 h following the last training bout. The sarcoplasmic protein pool was assayed for proteins involved in energy metabolism, and the myofibril protein pool was assayed for relative myosin heavy chain (MHC) and actin protein abundances. Sections were also histologically analyzed to obtain myofibril spacing characteristics. VAR resulted in ~12% greater volume load (VL) compared to CON (p < 0.001). The mean fiber cross-sectional area increased following both RT protocols [CON: 14.6% (775.5 μm2), p = 0.006; VAR: 13.9% (743.2 μm2), p = 0.01 vs. PRE for both], but without significant differences between protocols (p = 0.79). Neither RT protocol affected a majority of assayed proteins related to energy metabolism, but both training protocols increased hexokinase 2 protein levels and decreased a mitochondrial beta-oxidation marker (VLCAD protein; p < 0.05). Citrate synthase activity levels increased with CON RT (p < 0.05), but not VAR RT. The relative abundance of MHC (summed isoforms) decreased with both training protocols (p < 0.05). However, the relative abundance of actin protein (summed isoforms) decreased with VAR only (13.5 and 9.0%, respectively; p < 0.05). A decrease in percent area occupied by myofibrils was observed from PRE to VAR (−4.87%; p = 0.048), but not for the CON (4.53%; p = 0.979). In contrast, there was an increase in percent area occupied by non-contractile space from PRE to VAR (10.14%; p = 0.048), but not PRE to CON (0.72%; p = 0.979). In conclusion, while both RT protocols increased muscle fiber hypertrophy, a higher volume-load where RT variables were frequently manipulated increased non-contractile spacing in resistance-trained individuals.

Artemisinin Improves Acetylcholine-Induced Vasodilatation in Rats with Primary Hypertension.

PurposeEndothelial dysfunction and the subsequent decrease in endothelium-dependent vascular relaxation of small arteries are major features of hypertension. Artemisinin, a well-known antimalarial drug, has been shown to exert protecting roles against endothelial cell injury in cardiac and pulmonary vascular diseases. The current study aimed to investigate the effects of artemisinin on endothelium-dependent vascular relaxation and arterial blood pressure, as well as the potential signalling pathways in spontaneously hypertensive rats (SHRs).MethodsIn this study, acetylcholine (ACh)-induced dose-dependent relaxation assays were performed to evaluate vascular endothelial function after treatment with artemisinin. Artemisinin was administered to the rats by intravenous injection or to arteries by incubation for the acute exposure experiments, and it was administered to rats by intraperitoneal injection for 28 days for the chronic experiments.ResultsBoth acute and chronic administration of artemisinin decreased the heart rate and improved ACh-induced endothelium-dependent relaxation but negligibly affected the arterial blood pressure in SHRs. Incubation with artemisinin decreased basal vascular tension, NAD(P)H oxidase activity and reactive oxygen species (ROS) levels, but it also increased endothelial nitric oxide (NO) synthase (eNOS) activity and NO levels in the mesenteric artery, coronary artery, and pulmonary artery of SHRs. Artemisinin chronic administration to SHRs increased the protein expression of eNOS and decreased the protein expression of the NAD(P)H oxidase subunits NOX-2 and NOX-4 in the mesenteric artery.ConclusionThese results indicate that treatment with artemisinin has beneficial effects on reducing the heart rate and basal vascular tension and improving endothelium-dependent vascular relaxation in hypertension, which might occur by increasing eNOS activation and NO release and inhibiting NAD(P)H oxidase derived ROS production.

Parkia speciosa Hassk. Empty Pod Extract Alleviates Angiotensin II-Induced Cardiomyocyte Hypertrophy in H9c2 Cells by Modulating the Ang II/ROS/NO Axis and MAPK Pathway.

Cardiac hypertrophy is characteristic of heart failure in patients who have experienced cardiac remodeling. Many medicinal plants, including Parkia speciosa Hassk., have documented cardioprotective effects against such pathologies. This study investigated the activity of P. speciosa empty pod extract against cardiomyocyte hypertrophy in H9c2 cardiomyocytes exposed to angiotensin II (Ang II). In particular, its role in modulating the Ang II/reactive oxygen species/nitric oxide (Ang II/ROS/NO) axis and mitogen-activated protein kinase (MAPK) pathway was examined. Treatment with the extract (12.5, 25, and 50 μg/ml) prevented Ang II-induced increases in cell size, NADPH oxidase activity, B-type natriuretic peptide levels, and reactive oxygen species and reductions in superoxide dismutase activity. These were comparable to the effects of the valsartan positive control. However, the extract did not significantly ameliorate the effects of Ang II on inducible nitric oxide synthase activity and nitric oxide levels, while valsartan did confer such protection. Although the extract decreased the levels of phosphorylated extracellular signal-related kinase, p38, and c-Jun N-terminal kinase, valsartan only decreased phosphorylated c-Jun N-terminal kinase expression. Phytochemical screening identified the flavonoids rutin (1) and quercetin (2) in the extract. These findings suggest that P. speciosa empty pod extract protects against Ang II-induced cardiomyocyte hypertrophy, possibly by modulating the Ang II/ROS/NO axis and MAPK signaling pathway via a mechanism distinct from valsartan.

Effects of peroxisome proliferator activated receptor gamma (PPARγ) agonist on fasting model applied neuron cultures

Abstract Objectives Peroxisome proliferator activated receptor gamma (PPARγ) agonists used for the treatment of Diabetes Mellitus (DM), has important roles on the regulation of metabolism including ketogenesis in fasting and low glucose states. Recently PPARγ was proven to have anti-oxidant and anti-inflammatory effects on neuronal cells. Methods In the present study, effects of pioglitazone (PPARγ agonist) on cell survival, energy metabolism and mitochondrial functions were investigated in glucose deprived fasting model applied SH-SY5Y (ATCC/CRL 2266) cell lines. Before and after pioglitazone treatment; energy metabolites (glucose, lactate, ketone (βOHB), lactate dehydrogenase activity), mitochondrial citrate synthase activity and cell viability were investigated. Results and Conclusions PPARγ agonist addition to glucose deprived, ketone added neurons provided positive improvements in energy metabolites (p&lt;0.01), mitochondrial functions (p&lt;0.001) and survival rates (p&lt;0.01). Changes in mitochondrial citrate synthase activity, lactate and LDH levels of neuronal cells treated with PPARγ agonist have not been previously shown. Our results suggest, pioglitazone as an effective alternative for the treatment of neurodegenerative diseases especially with the presence of ketone bodies. By clarifying the mechanisms of PPARγ agonists, a great contribution will be made to the treatment of neurodegenerative diseases.

Knockdown of PGM1 enhances anticancer effects of orlistat in gastric cancer under glucose deprivation

BackgroundPhosphoglucomutase 1 (PGM1) acts as an important regulator in glucose metabolism. However, the role of PGM1 in gastric cancer (GC) remains unclear. This study aims to investigate the role of PGM1 and develop novel regimens based on metabolic reprogramming in GC.MethodsCorrelation and enrichment analyses of PGM1 were conducted based on The Cancer Genome Atlas database. Data derived from the Kaplan–Meier Plotter database were analyzed to evaluate correlations between PGM1 expression and survival time of GC patients. Cell counting kit-8, 5-Ethynyl-2-deoxyuridine, flow cytometry assays, generation of subcutaneous tumor and lung metastasis mouse models were used to determine growth and metastasis in vitro and in vivo. Cell glycolysis was detected by a battery of glycolytic indicators, including lactate, pyruvic acid, ATP production and glucose uptake. Fatty Acid Synthase (FASN) activity and expression levels of lipid enzymes were determined to reflect on lipid metabolism.ResultsCorrelation and enrichment analyses suggested that PGM1 was closely associated with cell viability, proliferation and metabolism. PGM1 was overexpressed in GC tissues and cell lines. High PGM1 expression served as an indicator of shorter survival for specific subpopulation of GC patients. It was also correlated with pathological tumor stage and pathological tumor node metastasis stage of GC. Under the glucose deprivation condition, knockdown of PGM1 significantly suppressed cell viability, proliferation and glycolysis, whereas lipid metabolism was enhanced. Orlistat, as a drug that was designed to inhibit FASN activity, effectively induced apoptosis and suppressed lipid metabolism in GC. However, orlistat conversely increased glycolytic levels. Orlistat exhibited more significant inhibitive effects on GC progression after knockdown of PGM1 under glucose deprivation due to combination of glycolysis and lipid metabolism both in vitro and in vivo.ConclusionsDownregulation of PGM1 expression under glucose deprivation enhanced anti-cancer effects of orlistat. This combination application may serve as a novel strategy for GC treatment.

Anti-inflammatory Effect of Astragali Radix Polysaccharide on Mice with Ulcerative Colitis

Objective: To explore the effect of Astragali radix polysaccharide on ulcerative colitis and its mechanism. Methods: Fifty SPF male mice were randomly divided into the normal control group, the model group, the high and low concentration APS group, and the positive group. The mouse model of acute ulcerative colitis was established with 5% dextran sulfate sodium salt. After the successful model establishment, the normal control and the model group were free to drink distilled water, the high and low concentration APS groups were free to drink 0.7 and 0.35 mg·mL−1 APS aqueous solution respectively, and the positive group was free to drink 1 μg·mL−1 dexamethasone aqueous solution for 7 consecutive days. Assessing disease activity index (DAI) of mice in each group, observing colonic pathological sections by HE, and detecting superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity, nitric oxide synthase (NOS) activity, malondialdehyde (MDA) content and nitric oxide (NO) levels in tissues, and then detecting interleukin-6 (IL-6), leukocyte-mediated Interleukin-1β (IL-1β), D-lactic acid (D-LA), diamine oxidase (DAO), and tumor necrosis factor-α (TNF-α) content in serum by ELISA method. Results: Compared with the DSS group, the high concentration APS group significantly (P<0.05) reduced the DAI score of mouse colitis, reduced the area of colon tissue ulcers and inflammatory cell infiltration, and restored the length of the colon, and the concentrations of IL-6, IL-1β, TNF-α and the levels of D-LA and DAO in the serum were significantly decreased. The activities of MPO, NOS, MDA and NO in colon tissue were obviously (P<0.05) decreased, while the activities of SOD were significantly (P<0.05) increased. Conclusion: The high concentration APS group had a notable effect on mice with ulcerative colitis, its effect was related to antioxidation, improvement of intestinal mucosal barrier function, and reduction of the release of inflammatory factors.

Nitric Oxide Increases Mitomycin-C Cytotoxicity by Generation of Reactive Oxygen Species and Induces Cell Death by Apoptosis in FancC-/- Cells

Fanconi Anemia (FA) is a rare genetic disorder and patients of FA exhibit progressive bone marrow failure, developmental defects and cancer predisposition. Mitochondrial dysfunction due to oxidative stress and higher levels of Reactive Oxygen Species (ROS) has been well documented in FA. Increase in the levels of Reactive Nitrogen Species (RNS) and Nitric Oxide Synthase (NOS) activity is often correlated with OS- related disorders which have altered mitochondrial function. Biological effects of Nitric Oxide (NO) and nitrosative stress depend on the cell type, concentration of NO, the time of incubation and cellular homeostasis. NO is known to have both prooncogenic as well as tumour -suppressing effects which are a result of regulation of S- nitrosylation, genome wide epigenetic changes and posttranslational modification of protein. NO plays strategic roles in metabolic and signalling pathways, making NO metabolism a key mediator in pathways that are responsible for supporting tumorigenesis. NO is also known to have important regulatory roles in the process of autophagy, which is an important mediator in the cross-talk with ROS and RNS. In the present study, we examined the interaction between ROS and NO, induction of apoptosis by NO and the possible role of NO in the pathogenesis of FA. Investigating the involvement of NO and NS and their interactions with the known hallmarks of FA will give a more comprehensive understanding of pathogenesis of FA.

MdFRK2-mediated sugar metabolism accelerates cellulose accumulation in apple and poplar

BackgroundCellulose is not only a common component in vascular plants, but also has great economic benefits for paper, wood, and industrial products. In addition, its biosynthesis is highly regulated by carbohydrate metabolism and allocation in plant. MdFRK2, which encodes a key fructokinase (FRK) in apple, showed especially high affinity to fructose and regulated carbohydrate metabolism.ResultsIt was observed that overexpression of MdFRK2 in apple decreased sucrose (Suc) and fructose (Fru) with augmented FRK activity in stems, and caused the alterations of many phenotypic traits that include increased cellulose content and an increase in thickness of the phloem region. To further investigate the involved mechanisms, we generated FRK2-OE poplar lines OE#1, OE#4 and OE#9 and discovered (1) that overexpression of MdFRK2 resulted in the huge increased cellulose level by shifting the fructose 6-phosphate or glucose 6-phsophate towards UDPG formation, (2) a direct metabolic pathway for the biosynthesis of cellulose is that increased cleavage of Suc into UDP-glucose (UDPG) for cellulose synthesis via the increased sucrose synthase (SUSY) activity and transcript levels of PtrSUSY1, (3) that the increased FRK activity increases the sink strength overall so there is more carbohydrate available to fuel increased cambial activity and that resulted in more secondary phloem. These results demonstrated that MdFRK2 overexpression would significantly changes the photosynthetic carbon flux from sucrose and hexose to UDPG for increased cellulose synthesis.ConclusionsThe present data indicated that MdFRK2 overexpression in apple and poplar changes the photosynthetic carbon flux from sucrose and hexose to UDPG for stem cellulose synthesis. A strategy is proposed to increase cellulose production by regulating sugar metabolism as a whole.