The role of adrenomedullin in Lyme disease
By Linda on Nov 16, 2010 in Infections | comments(0)
Excerpt:
Borrelia burgdorferi stimulates a strong inflammatory response
during infection of a mammalian host. To understand the
mechanisms of immune regulation employed by the host to control
this inflammatory response, we focused our studies on
adrenomedullin, a peptide produced in response to bacterial
stimuli that exhibits antimicrobial activity and regulates
inflammatory responses by modulating the expression of
inflammatory cytokines. Specifically, we investigated the effect
of B. burgdorferi on the expression of adrenomedullin as well as
the ability of adrenomedullin to dampen host inflammatory
responses to the spirochete. The concentration of adrenomedullin
in the synovial fluid of untreated Lyme arthritis patients was
elevated compared with control osteoarthritis patient samples. In
addition, co-culture with B. burgdorferi significantly increased
the expression of adrenomedullin in RAW264.7 macrophages through
MyD88-, PI3-K-, and p38-dependent signaling cascades.
Furthermore, the addition of exogenous adrenomedullin to B.
burgdorferi-stimulated RAW264.7 macrophages resulted in a
significant decrease in the induction of pro-inflammatory
cytokines. Taken together, these results suggest that B.
burgdorferi increases the production of The role of adrenomedullin in Lyme disease.
