Antiinflammatory actions of cat's claw: the role of NF-kappaB.
BACKGROUND
Uncaria tomentosa is a vine commonly known as cat's claw or 'uña de gato' (UG) and is used in traditional Peruvian medicine for the treatment of a wide range of health problems, particularly digestive complaints and arthritis.


OBJECTIVE
The aim of this study was to determine the proposed anti-inflammatory properties of cat's claw. Specifically: (i) does a bark extract of cat's claw protect against oxidant-induced stress in vitro, and (ii) to determine if UG modifies transcriptionally regulated events.


METHODS
Cell death was determined in two cell lines, RAW 264.7 and HT29 in response to peroxynitrite (PN, 300 microM). Gene expression of inducible nitric oxide synthase (iNOS) in HT29 cells, direct effects on nitric oxide and peroxynitrite levels, and activation of NF-kappaB in RAW 264.7 cells as influenced by UG were assessed. Chronic intestinal inflammation was induced in rats with indomethacin (7.5 mg/kg), with UG administered orally in the drinking water (5 mg/mL).


RESULTS
The administration of UG (100 microg/mL) attenuated (P < 0.05) peroxynitrite-induced apoptosis in HT29 (epithelial) and RAW 264.7 cells (macrophage). Cat's claw inhibited lipopolysaccharide-induced iNOS gene expression, nitrite formation, cell death and inhibited the activation of NF-kappaB. Cat's claw markedly attenuated indomethacin-enteritis as evident by reduced myeloperoxidase activity, morphometric damage and liver metallothionein expression.


CONCLUSIONS
Cat's claw protects cells against oxidative stress and negated the activation of NF-kappaB. These studies provide a mechanistic evidence for the widely held belief that cat's claw is an effective anti-inflammatory agent.
Sandoval-Chacón
M
M
LSU Medical Center, Department of Paediatrics and Stanley S. Scott Cancer Center, New Orleans, LA 70112, USA.
Thompson
J H
JH
Zhang
X J
XJ
Liu
X
X
Mannick
E E
EE
Sadowska-Krowicka
H
H
Charbonnet
R M
RM
Clark
D A
DA
Miller
M J
MJ
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D017209:Apoptosis; D002470:Cell Survival; D002478:Cells, Cultured; D004586:Electrophoresis / Q000379:methods; D004789:Enzyme Activation; D005786:Gene Expression Regulation / Q000187:drug effects; D019073:HT29 Cells; D006801:Humans; D007213:Indomethacin; D007249:Inflammation / Q000139:chemically induced; D008297:Male; D008668:Metallothionein / Q000378:metabolism; D016328:NF-kappa B / Q000096:biosynthesis* / Q000235:genetics; D009566:Nitrates / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D018384:Oxidative Stress / Q000187:drug effects*; D009195:Peroxidase / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley
D000893:Anti-Inflammatory Agents; D016328:NF-kappa B; D009566:Nitrates; D010936:Plant Extracts; D012333:RNA, Messenger; C039642:peroxynitric acid; D009569:Nitric Oxide; D008668:Metallothionein; D009195:Peroxidase; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D007213:Indomethacin