File Download
  Links for fulltext
     (May Require Subscription)
Supplementary

postgraduate thesis: Effects of serotonin on LPS- or LTA- stimulated cytokine release in monocytes and macrophages

TitleEffects of serotonin on LPS- or LTA- stimulated cytokine release in monocytes and macrophages
Authors
Issue Date2014
PublisherThe University of Hong Kong (Pokfulam, Hong Kong)
Citation
Wong, B. [黃沛珊]. (2014). Effects of serotonin on LPS- or LTA- stimulated cytokine release in monocytes and macrophages. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5303984
AbstractChronic obstructive pulmonary disease (COPD) is a progressive disease and characterized by persistent airflow limitation. Pathophysiologically it involves many components, including oxidative stress and inflammation of the airways and lungs. Although the primary cause of COPD is smoking, acute exacerbation due to infections can accelerate disease progression, which is a significant cause of morbidity, mortality and burden on healthcare costs. One-half of all acute exacerbations of COPD are associated with bacterial infection, with non-typeable Hemophilus influenzae being the most common pathogen. Staphylococcus pneumonia, one of the most common Gram-positive bacterial pathogens, is also involved in airway infections, either primary or subsequent to viral diseases. To COPD patients the common respiratory pathogens include Gram-negative and Gram-positive bacterial species. Lipopolysaccharide (LPS), a major component of the outer membrane of all Gram-negative bacteria, which is the predominant inducer of inflammatory responses, has been widely studied. On the other hand, less is known about Gram-positive bacteria, which do not contain LPS but express lipoteichoic acid (LTA) as an important proinflammatory constituent in their cell wall. Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter that plays an important role in regulating pulmonary function and pathogenesis of inflammation. In this study, we hypothesize that the serotoninergic system may be involved in LPS- and LTA-induced inflammation in COPD. Since monocyte recruitment to lung is a key step in COPD, this study aims to investigate the effects of LPS or LTA alone and in combination of 5-HT pretreatment on the release of pro-inflammatory cytokines in undifferentiated (i.e. monocytes) and differentiated THP-1 cells (i.e. macrophages). LPS, LTA or 5-HT alone induced the release of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in both monocytes and macrophages. Our findings also showed that 5-HT pretreatment suppressed the LPS-induced IL-8 and MCP-1 release, suggesting that 5-HT might act as an anti-inflammatory mediator. On the other hand, 5-HT pretreatment enhanced the LTA-induced IL-8 and MCP-1 release, indicating that 5-HT might also act as a pro-inflammatory mediator. These results demonstrate that 5-HT may be involved in the differential modulation of inflammatory processes during Gram-negative or Gram-positive infections in COPD.
DegreeMaster of Medical Sciences
SubjectCytokines
Monocytes
Macrophages
Serotonin
Dept/ProgramMedicine
Persistent Identifierhttp://hdl.handle.net/10722/206489

 

DC FieldValueLanguage
dc.contributor.authorWong, Bauhinia-
dc.contributor.author黃沛珊-
dc.date.accessioned2014-11-03T23:14:49Z-
dc.date.available2014-11-03T23:14:49Z-
dc.date.issued2014-
dc.identifier.citationWong, B. [黃沛珊]. (2014). Effects of serotonin on LPS- or LTA- stimulated cytokine release in monocytes and macrophages. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b5303984-
dc.identifier.urihttp://hdl.handle.net/10722/206489-
dc.description.abstractChronic obstructive pulmonary disease (COPD) is a progressive disease and characterized by persistent airflow limitation. Pathophysiologically it involves many components, including oxidative stress and inflammation of the airways and lungs. Although the primary cause of COPD is smoking, acute exacerbation due to infections can accelerate disease progression, which is a significant cause of morbidity, mortality and burden on healthcare costs. One-half of all acute exacerbations of COPD are associated with bacterial infection, with non-typeable Hemophilus influenzae being the most common pathogen. Staphylococcus pneumonia, one of the most common Gram-positive bacterial pathogens, is also involved in airway infections, either primary or subsequent to viral diseases. To COPD patients the common respiratory pathogens include Gram-negative and Gram-positive bacterial species. Lipopolysaccharide (LPS), a major component of the outer membrane of all Gram-negative bacteria, which is the predominant inducer of inflammatory responses, has been widely studied. On the other hand, less is known about Gram-positive bacteria, which do not contain LPS but express lipoteichoic acid (LTA) as an important proinflammatory constituent in their cell wall. Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter that plays an important role in regulating pulmonary function and pathogenesis of inflammation. In this study, we hypothesize that the serotoninergic system may be involved in LPS- and LTA-induced inflammation in COPD. Since monocyte recruitment to lung is a key step in COPD, this study aims to investigate the effects of LPS or LTA alone and in combination of 5-HT pretreatment on the release of pro-inflammatory cytokines in undifferentiated (i.e. monocytes) and differentiated THP-1 cells (i.e. macrophages). LPS, LTA or 5-HT alone induced the release of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in both monocytes and macrophages. Our findings also showed that 5-HT pretreatment suppressed the LPS-induced IL-8 and MCP-1 release, suggesting that 5-HT might act as an anti-inflammatory mediator. On the other hand, 5-HT pretreatment enhanced the LTA-induced IL-8 and MCP-1 release, indicating that 5-HT might also act as a pro-inflammatory mediator. These results demonstrate that 5-HT may be involved in the differential modulation of inflammatory processes during Gram-negative or Gram-positive infections in COPD.-
dc.languageeng-
dc.publisherThe University of Hong Kong (Pokfulam, Hong Kong)-
dc.relation.ispartofHKU Theses Online (HKUTO)-
dc.rightsCreative Commons: Attribution 3.0 Hong Kong License-
dc.rightsThe author retains all proprietary rights, (such as patent rights) and the right to use in future works.-
dc.subject.lcshCytokines-
dc.subject.lcshMonocytes-
dc.subject.lcshMacrophages-
dc.subject.lcshSerotonin-
dc.titleEffects of serotonin on LPS- or LTA- stimulated cytokine release in monocytes and macrophages-
dc.typePG_Thesis-
dc.identifier.hkulb5303984-
dc.description.thesisnameMaster of Medical Sciences-
dc.description.thesislevelMaster-
dc.description.thesisdisciplineMedicine-
dc.description.naturepublished_or_final_version-
dc.identifier.doi10.5353/th_b5303984-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats