Adenosine triphosphate (ATP) is well-known as a universal source of energy in living cells. Less known is that this molecule has a variety of important signaling functions: it activates a variety of specific metabotropic (P2Y) and ionotropic (P2X) receptors in neuronal and non-neuronal cell membranes. So, a wide variety of signaling functions well fits the ubiquitous presence of ATP in the tissues. Even more ubiquitous are protons. Apart from the unspecific interaction of protons with any protein, many physiological processes are affected by protons acting on specific ionotropic receptors-acid-sensing ion channels (ASICs). Both protons (acidification) and ATP are locally elevated in various pathological states. Using these fundamentally important molecules as agonists, ASICs and P2X receptors signal a variety of major brain pathologies. Here we briefly outline the physiological roles of ASICs and P2X receptors, focusing on the brain pathologies involving these receptors.
Humans ; Acid Sensing Ion Channels ; Protons ; Neurons ; Brain Diseases ; Adenosine Triphosphate/physiology*

As an important signal molecule, extracellular ATP(eATP) can regulate many physiological and biochemical responses to plant stress. In this study, the regulation of extracellular ATP(eATP) on chlorophyll content and chlorophyll fluorescence parameters of Angelica sinensis seedlings were studied under drought and low temperature stress. The results showed that all the chlorophyll content, the actual photochemical efficiency [Y(Ⅱ)], the electron transfer rate(ETR), the photochemical quenching coefficient(qP and qL) of A. sinensis leaves were significantly decreased under drought and low temperature stress, respectively. At the same time, non-photochemical quenching(NPQ and qN) were also all significantly increased, respectively. The application of eATP alleviated the decrease of chlorophyll content, Y(Ⅱ), ETR, qP and qL of A. sinensis leaves under drought and low temperature stress, and eliminated the increase of qN and NPQ. The results indicated that eATP could effectively increase the open ratio of PSⅡ reaction centers, and improve the electron transfer rate and light energy conversion efficiency of PSⅡ of A. sinensis leaves under drought and low temperature stress. It is beneficial to enhance the chlorophyll synthesis and the adaptability of PSⅡ about A. sinensis seedlings to drought and low temperature stress.
Adenosine Triphosphate ; pharmacology ; Angelica sinensis ; chemistry ; physiology ; Chlorophyll ; analysis ; Cold Temperature ; Droughts ; Fluorescence ; Photosynthesis ; Plant Leaves ; chemistry ; Seedlings ; chemistry ; physiology ; Stress, Physiological ; Water

BACKGROUND: Irritable bowel syndrome (IBS) is one of the most common functional intestinal diseases, but its pathogenesis is still unknown. The present study aimed to screen the differentially expressed proteins in the mucosa of colon between IBS with diarrhea (IBS-D) patients and the healthy controls. METHODS: Forty-two IBS-D patients meeting the Rome III diagnostic criteria and 40 control subjects from July 2007 to June 2009 in Chinese PLA General Hospital were enrolled in the present study. We examined the protein expression profiles in mucosa of colon corresponding to IBS-D patients (n = 5) and controls (n = 5) using 2-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS). Secondly, Western blot and immunohistochemical analysis were carried out to validate the screened proteins in 27 IBS-D patients and 27 controls. Thirdly, high-performance liquid chromatography (HPLC) was further carried out to determine ATP concentration in the mucosa of colon between 10 IBS-D patients and 8 controls. Comparisons between 2 groups were performed by Student's t-test or Mann-Whitney U-test. RESULTS: Twelve differentially expressed proteins were screened out. The α-enolase (ENOA) in the sigmoid colon (0.917 ± 0.007 vs. 1.310 ± 0.100, t = 2.643, P = 0.017) and caecum (0.765 ± 0.060 vs. 1.212 ± 0.122, t = 2.225, P = 0.023), Isobutyryl-CoA dehydrogenase (ACAD8) in the sigmoid colon (1.127 ± 0.201 vs. 1.497 ± 0.392, t = 7.093, P = 0.008) of the IBS-D group were significantly lower while acetyl-CoA acetyltransferase (CT) in the caecum (2.453 ± 0.422 vs. 0.931 ± 0.652, t = 8.363, P = 0.015) and ATP synthase subunit d (ATP5H) in the sigmoid (0.843 ± 0.042 vs. 0.631 ± 0.042, t = 8.613,P = 0.007) of the IBS-D group was significantly higher, compared with the controls. The ATP concentration in the mucosa of the sigmoid colon in IBS-D group was significantly lower than that of control group (0.470 [0.180, 1.360] vs. 5.350 [2.230, 7.900], U = 55, P < 0.001). CONCLUSIONS Many proteins related to energy metabolism presented differential expression patterns in the mucosa of colon of the IBS-D patients. The abnormalities in energy metabolism may be involved in the pathogenesis of IBS which deserves more studies to elucidate.
Adenosine Triphosphate ; metabolism ; Adult ; Blotting, Western ; Colon ; metabolism ; pathology ; Diarrhea ; enzymology ; metabolism ; pathology ; Electrophoresis, Gel, Two-Dimensional ; Energy Metabolism ; genetics ; physiology ; Female ; Humans ; Immunohistochemistry ; Intestinal Mucosa ; enzymology ; metabolism ; pathology ; Irritable Bowel Syndrome ; enzymology ; metabolism ; pathology ; Male ; Mass Spectrometry ; Middle Aged ; Proteome ; metabolism

OBJECTIVE: To investigate the effects of salvianolic acid A (SAA) on cardiomyocyte apoptosis and mitochondrial dysfunction in response to hypoxia/reoxygenation (H/R) injury and to determine whether the Akt signaling pathway might play a role. METHODS: An in vitro model of H/R injury was used to study outcomes on primary cultured neonatal rat cardiomyocytes. The cardiomyocytes were treated with 12.5, 25, 50 μg/mL SAA at the beginning of hypoxia and reoxygenation, respectively. Adenosine triphospate (ATP) and reactive oxygen species (ROS) levels were assayed. Cell apoptosis was evaluated by flow cytometry and the expression of cleaved-caspase 3, Bax and Bcl-2 were detected by Western blotting. The effects of SAA on mitochondrial dysfunction were examined by determining the mitochondrial membrane potential (△Ψm) and mitochondrial permeability transition pore (mPTP), followed by the phosphorylation of Akt (p-Akt) and GSK-3β (p-GSK-3β), which were measured by Western blotting. RESULTS: SAA significantly preserved ATP levels and reduced ROS production. Importantly, SAA markedly reduced the number of apoptotic cells and decreased cleaved-caspase 3 expression levels, while also reducing the ratio of Bax/Bcl-2. Furthermore, SAA prevented the loss of △Ψm and inhibited the activation of mPTP. Western blotting experiments further revealed that SAA significantly increased the expression of p-Akt and p-GSK-3β, and the increase in p-GSK-3β expression was attenuated after inhibition of the Akt signaling pathway with LY294002. CONCLUSION SAA has a protective effect on cardiomyocyte H/R injury; the underlying mechanism may be related to the preservation of mitochondrial function and the activation of the Akt/GSK-3β signaling pathway.
Adenosine Triphosphate ; analysis ; Animals ; Animals, Newborn ; Caffeic Acids ; pharmacology ; Cell Hypoxia ; Cells, Cultured ; Glycogen Synthase Kinase 3 beta ; physiology ; Lactates ; pharmacology ; Mitochondria, Heart ; drug effects ; physiology ; Mitochondrial Membrane Transport Proteins ; drug effects ; Myocytes, Cardiac ; drug effects ; Proto-Oncogene Proteins c-akt ; physiology ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Signal Transduction ; physiology

Mitochondrial dynamics, involving mitochondrial fusion, fission and autophagy, plays an important role in maintaining cellular physiological function and homeostasis. Mitochondria are the "energy plant" of human body, so the changes of mitochondrial fusion, division and autophagy are important for cell respiration and energy production. On the other hand, energy metabolism influences mitochondrial dynamics in turn. This paper reviewed the recent advances in studies on the relationship between energy metabolism and the proteins regulating mitochondrial fusion, fission and autophagy. The association of mitochondrial dynamics with electron chain complex expression, oxidative phosphorylation and ATP synthesis upon exercise intervention will provide theoretical references for the further studies in sports training and disease intervention.
Adenosine Triphosphate ; biosynthesis ; Autophagy ; Energy Metabolism ; Exercise ; Humans ; Mitochondria ; physiology ; Mitochondrial Dynamics ; Mitochondrial Proteins ; metabolism

Vitamin D deficiency is a common health issue around the world. We therefore evaluated the associations of semen quality with both serum and seminal plasma vitamin D levels and studied the mechanisms underlying these by incubating spermatozoa with 1,25(OH)₂D In vitro. Two hundred and twenty-two men were included in our study. Vitamin D was detected using an electrochemiluminescence method. Spermatozoa used for In vitro experiments were isolated by density gradient centrifugation. Positive relationships of serum 25(OH)D with semen volume and seminal plasma fructose were identified. Seminal plasma 25(OH)D level showed no relationship with serum 25(OH)D level, while it was inversely associated with sperm concentration and positively correlated with semen volume and sperm kinetic values. In vitro, sperm kinetic parameters increased after incubation with 1,25(OH)₂D, especially upon incubation for 30 min with it at a concentration of 0.1 nmol l^-1. Under these incubation conditions, the upward migration of spermatozoa increased remarkably with increasing adenosine triphosphate (ATP) concentration. The concentration of cyclic adenosine monophosphate (cAMP) and the activity of protein kinase A (PKA) were both elevated, and the PKA inhibitor, N-[2-(p-Bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride (H89) reversed the increase of ATP production. The concentrations of cytoplasmic calcium ions and nicotinamide adenine dinucleotide (NADH) were both enhanced, while mitochondrial calcium uniporter (MCU) inhibitor, Ruthenium 360 (Ru360) did not reverse the increase of ATP production. Therefore, seminal plasma vitamin D may be involved in regulating sperm motility, and 1,25(OH)₂D may enhance sperm motility by promoting the synthesis of ATP both through the cAMP/PKA pathway and the increase in intracellular calcium ions.
Adenosine Triphosphate/metabolism* ; Adult ; Calcium/metabolism* ; Cyclic AMP/metabolism* ; Cyclic AMP-Dependent Protein Kinases/metabolism* ; Humans ; Male ; Semen/metabolism* ; Semen Analysis ; Signal Transduction/physiology* ; Sperm Motility/physiology* ; Spermatozoa/metabolism* ; Vitamin D/pharmacology* ; Vitamin D Deficiency/blood* ; Wit and Humor as Topic ; Young Adult

OBJECTIVE: To explore the role of mitochondrial permeability transition pore (mPTP) in mediating the protective effect of gastrodin against oxidative stress damage in H9c2 cardiac myocytes. METHODS: H9c2 cardiac myocytes were treated with HO, gastrodin, gastrodin+HO, cyclosporin A (CsA), or CsA+gas+HO group. MTT assay was used to detect the survival ratio of H9c2 cells, and flow cytometry with Annexin V-FITC/PI double staining was used to analyze the early apoptosis rate after the treatments. The concentration of ATP and level of reactive oxygen species (ROS) in the cells were detected using commercial kits. The mitochondrial membrane potential of the cells was detected with laser confocal microscopy. The expression of cytochrome C was detected with Western blotting, and the activity of caspase-3 was also assessed in the cells. RESULTS: Gastrodin pretreatment could prevent oxidative stress-induced reduction of mitochondrial membrane potential, and this effect was inhibited by the application of CsA. Gastrodin significantly lowered the levels of ROS and apoptosis-related factors in HO-exposed cells, and such effects were reversed by CsA. CsA significantly antagonized the protective effect of gastrodin against apoptosis in HO-exposed cells. CONCLUSIONS Gastrodin prevents oxidative stress-induced injury in H9c2 cells by inhibiting mPTP opening to reduce the cell apoptosis.
Adenosine Triphosphate ; analysis ; Apoptosis ; drug effects ; Benzyl Alcohols ; antagonists & inhibitors ; pharmacology ; Caspase 3 ; analysis ; Cell Line ; Cell Survival ; drug effects ; Cyclosporine ; pharmacology ; Cytochromes c ; analysis ; Glucosides ; antagonists & inhibitors ; pharmacology ; Humans ; Hydrogen Peroxide ; antagonists & inhibitors ; pharmacology ; Membrane Potential, Mitochondrial ; drug effects ; Mitochondrial Membrane Transport Proteins ; physiology ; Myocytes, Cardiac ; drug effects ; metabolism ; Oxidative Stress ; Reactive Oxygen Species ; analysis

ABC transporters form the largest of all transporter families, and their structural study has made tremendous progress over recent years. However, despite such advances, the precise mechanisms that determine the energy-coupling between ATP hydrolysis and the conformational changes following substrate binding remain to be elucidated. Here, we present our thermodynamic analysis for both ABC importers and exporters, and introduce the two new concepts of differential-binding energy and elastic conformational energy into the discussion. We hope that the structural analysis of ABC transporters will henceforth take thermodynamic aspects of transport mechanisms into account as well.
ATP-Binding Cassette Transporters ; physiology ; Adenosine Triphosphate ; metabolism ; Animals ; Humans ; Models, Theoretical ; Thermodynamics

Nucleotides have unambiguously emerged as a family of mediators of intercellular communication, which bind a class of plasma membrane receptors, P2 purinergic receptors, to trigger intercellular signaling. P2 receptors can be further divided into two structurally and functionally different sub-famlies, the P2X and P2Y receptors. Different blood cells express diverse spectrum of P2 receptors at different levels. Extracellular adenosine triphosphate (ATP) exerts different effects on blood cells, regulating cell proliferation, differentiation, migration, chemotaxis, release of cytokines or lysosomal constituents, and generation of reactive oxygen or nitrogen species. The relationship between abnormal P2 receptors and human diseases attracts more and more attention. This review briefly discusses the expression and function of P2 receptors in hematopoietic system.
Adenosine Triphosphate ; Blood Cells ; physiology ; Cell Differentiation ; Cell Movement ; Cell Proliferation ; Hematopoiesis ; Humans ; Receptors, Purinergic P2 ; physiology ; Signal Transduction

Although the effects of the rice bran have recently been investigated, there is no information regarding platelet physiology available. However, it is well known that fermented natural plants have a beneficial effect on cardiovascular diseases. Therefore, this study was conducted to investigate whether fermented rice bran extract (FRBE) with several plants (Artemisia princeps, Angelica Gigantis Radix, Cnidium officinale, and Camellia sinensis) affected agonist-induced platelet aggregation, and if so, what the underlying mechanism of its activity was. We performed several experiments, including in vitro platelet aggregation, intracellular calcium concentration and adenosine triphosphate release. In addition, the activation of integrin alphaIIbbeta3 was determined using fibrinogen binding. Thrombus formation was also evaluated in vivo using an arterio-venous shunt model. The FRBE inhibited collagen-induced platelet aggregation in a concentration-dependent manner. FRBE significantly and dose dependently attenuated thrombus formation using rat arterio-venous shunt. FRBE suppressed the intracellular calcium mobilization in collagen-stimulated platelets. We also found that FRBE inhibited extracellular stimuli-responsive kinase 1/2, p38-mitogen-activated protein kinases and c-Jun N-terminal kinase phosphorylation. These results suggested that FRBE inhibited collagen-induced platelet aggregation, which was mediated by modulation of downstream signaling molecules. In conclusion, FRBE could be developed as a functional food against aberrant platelet activation-related cardiovascular diseases.
Adenosine Triphosphate ; Angelica ; Animals ; Blood Platelets ; Calcium ; Camellia ; Cardiovascular Diseases ; Cnidium ; Collagen ; Fibrinogen ; Functional Food ; JNK Mitogen-Activated Protein Kinases ; Phosphorylation ; Phosphotransferases ; Physiology ; Platelet Aggregation ; Platelet Glycoprotein GPIIb-IIIa Complex ; Protein Kinases ; Rats ; Thrombosis