Andrographolide interferes with T cell activation and reduces experimental autoimmune encephalomyelitis in the mouse.
Andrographolide is a bicyclic diterpenoid lactone derived from extracts of Andrographis paniculata, a plant indigenous to South Asian countries that shows anti-inflammatory properties. The molecular and cellular bases for this immunomodulatory capacity remain unknown. Here, we show that andrographolide is able to down-modulate both humoral and cellular adaptive immune responses. In vitro, this molecule was able to interfere with T cell proliferation and cytokine release in response to allogenic stimulation. These results were consistent with the observation that T cell activation by dendritic cells (DCs) was completely abolished by exposing DCs to andrographolide during antigen pulse. This molecule was able to interfere with maturation of DCs and with their ability to present antigens to T cells. Furthermore, in vivo immune responses such as antibody response to a thymus-dependent antigen and delayed-type hypersensitivity were drastically diminished in mice by andrographolide treatment. Finally, the ability of andrographolide to inhibit T cell activation was applied to interfere with the onset of experimental autoimmune encephalomyelitis (EAE), an inflammatory demyelinating disease of the central nervous system that is primarily mediated by CD4(+) T cells and serves as an animal model for human multiple sclerosis. Treatment with andrographolide was able to significantly reduce EAE symptoms in mice by inhibiting T cell and antibody responses directed to myelin antigens. Our data suggest that andrographolide is able to efficiently block T cell activation in vitro, as well as in vivo, a feature that could be useful for interfering with detrimental T cell responses.
Iruretagoyena
Mirentxu I
MI
Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile.
Tobar
Jaime A
JA
González
Pablo A
PA
Sepúlveda
Sofía E
SE
Figueroa
Claudio A
CA
Burgos
Rafael A
RA
Hancke
Juan L
JL
Kalergis
Alexis M
AM
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D004224:Diterpenes / Q000494:pharmacology / Q000627:therapeutic use*; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000188:drug therapy*; D005260:Female; D007109:Immunity / Q000187:drug effects; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D009186:Myelin Sheath / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects* / Q000502:physiology
D000893:Anti-Inflammatory Agents; D004224:Diterpenes; C030419:andrographolide