Dissertation > Excellent graduate degree dissertation topics show

Regulating Mechanisms of Superoxide Anion and Nitric Oxide Generation in Macrophages

Author: LiZuo
Tutor: GaoQiuHua
School: Huazhong University of Science and Technology
Course: Inorganic Chemistry
Keywords: macrophage superoxide melatonin Ferulic acid tetramethylpyrazine nitric oxide iNOS
CLC: Q26
Type: Master's thesis
Year: 2005
Downloads: 157
Quote: 0
Read: Download Dissertation

Abstract


Macrophages, one of the key mediators of the immune system, generate large quantities of superoxide in response to a variety of stimuli, by a coordinated sequence of biochemical reactions known as the respiratory burst. At the same time, upon stimulation by certain cytokines, the iNOS gene of macrophages is induced and large amount of NO is generated. Melatonin is a derivative of tryptophan mainly synthesized in the pineal gland of mammals, which shows hypnotization and immune-regulatory functions in vivo. Recent studies revealed that melatonin acts as a potent antioxidant in vitro. Ferulic acid and tetramethylpyrazine are two active ingredients of Chinese herbal medicine Ligusticum wallichi Franchat. Excessive production of reactive oxygen species (ROS; including superoxide, nitric oxide and peroxynitrite) by macrophages has been implicated in a number of pathological processes. Accordingly, drugs that inhibit ROS generation may have beneficial effects in the treatment of diseases due to overproduction of ROS. In the present investigation, chemiluminescence by the generation of superoxide anion and burst respiratory was related with the production of nitric oxide. The effects of melatonin on the generation of superoxide anion and nitric oxide in stimulated murine macrophages were studied by luminol-enhanced chemiluminescence and EPR techniques, and the underlying molecular mechanisms were discussed. Melatonin pretreatment significantly scavenges the superoxide anion generated by macrophages, and inhibits the generation of nitric oxide. Ferulic acid, but not tetramethylpyrazine, scavenges superoxide anion dose-dependently. Western blot and RT-PCR analysis showed that melatonin decreased LPS/IFN-γ-induced iNOS gene expression. Tetramethylpyrazine also inhibits the expression of iNOS gene, and consequently decreases the formation of nitric oxide. However, ferulic acid shows no effect on iNOS expression and NO production. Further investigation suggested that melatonin significantly inhibited the degradation of cytoplasmic IκB-α, and blocked the translocation of p65/RelA into the nuclei. The results show that melatonin is an effective modulator on macrophages, which scavenges endogenous superoxide anion dose-dependently, inhibits the expression of iNOS gene via modulating the NF-κB signaling pathway, and consequently decreases the formation of nitric oxide. Therefore, it was suggested that melatonin, ferulic acid and tetramethylpyrazine might be the potential therapeutic and defense agents for diseases associated with the over activation of macrophages. The protective effects of extracts of Ligusticum wallichi Franchat against ischemic injury might be due to the scavenging of superoxide anion and the regulation of NO production.

Related Dissertations

  1. Study in Situ on Rat Intestinal Absorption Mechanism of Bazhen Decoction,R285
  2. Study on the Green Synthesis of Melatonin,R914
  3. Studies on the Effects of Exogenous Nitric Oxide on Rice under Cadmium Stress,S511
  4. Study on Heat Resistance of Chrysanthemum Floral Organ and Effects of Exogenously Nitric Oxide on Heat Resistance of Chrysanthemum,S682.11
  5. Effect of High Glucose on Chemokine Ligand 16 (CXCL16) Expression and Secretion in THP-1 Macrophages and Intervention of Aspirin in the Activity,R587.2
  6. Tissue-engineered Construction and Preliminary Implantation Study of Diamond-like Carbon Films for Artificial Mechanical Valve Applications,R654.2
  7. Kinase Activities Analysis and Localization of ZmCCaMK Induced by Abscisic Acid in Leaves of Maize Plants,S513
  8. Linear Regression and Grey Relational in the Correlation Analysis of Shanxi Overmature Vinegar’s Quality Inspection,TS264.22
  9. Noble Dendrobium Polysaccharides Attenuate Learning and Memory Deficits Induced by Lipopolysaccharide and Its Mechanisms in Rats,R285.5
  10. Effects of Cold-adaptation Swimming on Hemorheology and Quantity of NO and NOS in Aorta of SD Rats in Acute Cold Water Stress,R87
  11. Study on Extraction and Properties of Superoxide Dismutase from Goose Blood,TS254.9
  12. The Effects of Prostaglantiain E1 to the Phenotype and Functional Activity of Macrophage Which in Mouse Uterus,R363
  13. Antioxidant Effects of Atorvastatin on Vascular Remodeling of Vascular Injury in Mice,R543
  14. Changes and Roles of Plasma Hydrogen Sulfide in Elderly Patients with Ischemic Heart Failure,R541.6
  15. The Relationship between Exhale Nitric Oxide and Serum Eosinophil Cationic Protein, IL-13, IL-8 in Acute Asthma Exacerbation,R562.25
  16. Effects of Hypothermia Resuscitation on PPAR-γ and Related Gene Expression in Rats Lung during Hemorrhagic Shock,R605.971
  17. The Relationship of Serum Adiponectin、Nitric Oxide Synthase and Carotid Atherosclerosis in Patients with Acute Cerebral Infarction,R743.33
  18. Shamisen Medicinal and Edible Herbs on glucose and lipid metabolism in the metabolic syndrome and antioxidant effects,R285.5
  19. Berberine on serum levels of superoxide dismutase and malondialdehyde levels in,R743.33
  20. Hyperaccumulators Solanum nigrum (Solanum nigrum L.) tolerance and accumulation of Cd physiological and molecular mechanism of,X173
  21. Soft tissue crush injury in rats induced reactivity of isolated thoracic aorta changes,R686

CLC: > Biological Sciences > Cell Biology > Cellular Biochemistry
© 2012 www.DissertationTopic.Net  Mobile