Akkradate Siriphorn. Comparison of genistein and Pueraria mirifica in their effects on phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/1) in rat lumbar spinal cord and dorsal root ganglion following sciatic nerve ligation crush. Master's Degree(Anatomy). Mahidol University. : Mahidol University, 2006.
Comparison of genistein and Pueraria mirifica in their effects on phosphorylation of extracellular signal-regulated kinase1/2 (ERK1/1) in rat lumbar spinal cord and dorsal root ganglion following sciatic nerve ligation crush
Abstract:
Estrogen treatment has been shown to enhance functional recovery and nerve
regeneration after sciatic nerve crush injury by activation of extracellular signalregulated
kinase1/2 (ERK1/2). The aim of this study was to compare the estrogenlike
action of phytoestrogens: genistein and Pueraria mirifica (a phytoestrogen
rich Thai herb) treatments in their effects on phosphorylation of ERK1/2. The
sciatic nerve of male Sprague-Dawley rat was crush injured by ligation with 4-0
silk thread for 15 min. Blind assessment on functional recovery was assessed by
walking tract analysis, a toe spread assay, to quantify the return of normal foot
function. The lumbar spinal cords and dorsal root ganglia (DRG) were studied the
expression of the ERK1/2 signaling protein by Western blot analysis and
immunocytochemistry staining. Sciatic functional index, an index of functional
recovery, was significantly higher in the genistein, and Pueraria mirifica treated
rats throughout regeneration after day 8 comparing to the group of normal saline
treatment. At day 3, the sciatic nerve ligation crush injury induced the ERK1/2
activation in motor neurons and glia cells in spinal cord. This activation, which
correlated to functional recovery, was enhanced by applying the genistein and
Pueraria mirifica. In DRG after sciatic nerve ligation crush injury, ERK1/2 was
also activated in neurons and satellite cells. Applying the genistein and Pueraria
mirifica reduced ERK1/2 activation in DRG which may play an important role in
inflammatory process after sciatic nerve injury. These results were inhibited with
ICI182,780, an estrogen receptor antagonist. This study suggests that genistein and
Pueraria mirifica as well as estrogen probably act to reduce inflammatory
response, promote nerve regeneration and functional recovery after peripheral
nerve injury and initiate researchers to investigate deeply into Pueraria mirifica
and manipulate them to serve the need for alternative medicine