The oriental spice
curcumin has anti-inflammatory and
antioxidant effects. When given orally before injury,
curcumin reduces
burn progression in a rat comb
burn model. The authors hypothesized that
intravenous administration of
curcumin after injury would reduce
burn progression and that its effects are mediated through
iron chelation. Two comb
burns were created on the dorsum of Sprague-Dawley rats (weight, 300 g) using a
brass comb with four rectangular prongs preheated in boiling water and applied for 30 seconds resulting in four rectangular 10 × 20 mm full-thickness
burns separated by three 5 × 20 mm unburned interspaces (zone of
ischemia). Animals were randomized to receive one of four doses of crude
curcumin or one of six doses of purified
curcumin intravenously 1 and 24 hours after injury. Another set of animals were randomized to
deferoxamine or control vehicle.
Wounds were observed at 7 days after injury for visual evidence of
necrosis in the unburned interspaces. Full-thickness biopsies from the interspaces were evaluated with
Hematoxylin and
Eosin staining 7 days after injury for evidence of
necrosis. The percentage of unburned interspaces undergoing
necrosis at 1 week by purified
curcumin doses was 0 μg/kg, 74%; 0.3 μg/kg, 58%; 1 μg/kg, 53%; 3 μg/kg, 37%; 10 μg/kg, 63%; 30 μg/kg, 53%; and 100 μg/kg, 26%. The differences among the groups were significant (P = .03). When compared with controls, the 1 and 3 μg/kg
curcumin treatment groups had significantly less progression of interspaces to
necrosis (P = .04 and .002) as did the 30 and 100 μg/kg treatment groups (P = .03 and <.001).
Deferoxamine did not reduce
burn progression. When administered intravenously 1 and 24 hours after injury, both crude and purified
curcumin reduce the percentage of unburned interspaces that undergo
necrosis in a rat hot comb
burn model. The effects of purified
curcumin appear to be bimodal, suggesting more than one mechanism of action. The effects of
curcumin do not appear to be mediated by
iron chelation.