Abstract
Extracts prepared from the leaves of Phyllostachys edulis (bamboo) have received attention in pharmacological research due to their potent
antitumor, anti-inflammatory, antimicrobial, and anti-ulcerogenic activities. In this
study, anti-inflammatory effects of a bamboo leaf extract on tumor necrosis factor
alpha-induced overproduction of interleukin 8, vascular endothelial growth factor,
and interleukin 6 in immortalized human keratinocytes were investigated for the first
time. In addition, wound-healing effects were evaluated in 3T3-swiss albino mouse
fibroblasts. Bamboo leaf extract and isoorientin inhibited the tumor necrosis factor
alpha-induced release of interleukin 8 and vascular endothelial growth factor. Furthermore,
isoorientin dose-dependently reduced levels of interleukin 6 in tumor necrosis factor
alpha-α-treated immortalized human keratinocytes cells. Wound healing was evaluated using
a modification of the classical scratch assay. For evaluation of the wound gap, a
new computerized method based on time-lapse microscopy was developed. It was shown
that bamboo leaf extract (10 µg/mL) improved wound closure by 28 % (12 h) and 54 %
(24 h), respectively. In concentrations of 50 µg/mL and above, bamboo leaf extract
inhibited cell migration without affecting cell viability. Isoorientin (10 µM) improved
wound closure by 29 % (12 h) and 56 % (24 h), respectively. Comparable to bamboo leaf
extract, higher concentrations of isoorientin prevented cell migration. It is suggested
that bamboo leaf extract as well as isoorientin have a dual activity – in higher doses,
they show anti-inflammatory effects, and in lower concentrations, they exert anti-angiogenic
activities.
Key words
Phyllostachys edulis
- Poaceae - bamboo - wound healing - anti-inflammatory - time-lapse microscopy
