Aegiceras corniculatum extract suppresses initial and late phases of inflammation in rat paw and attenuates the production of eicosanoids in rat neutrophils and human platelets.
OBJECTIVE
The present study is designed to explore the anti-inflammatory potential of Aegiceras corniculatum Linn. Blanco stems extracts and their mechanism of action against various pro-inflammatory mediators and to validate its traditional use against inflammatory diseases.


METHODS
Rat paw edema and peritonitis models were employed for in vivo studies. For in vitro studies human platelets and rat neutrophils were stimulated with Ca(2+)-ionophore A23187 leading to the production of various pro-inflammatory metabolites, i.e., 12-HTT, 12-HETE and LTB(4) and 5-HETE which were quantified by HPLC.


RESULTS
The highly polar methanol extract (100mg/kg) caused approximately 90% reduction in the carrageenan- and prostaglandin E2-induced paw edema in rats. It also caused the inhibition of cycloxygenase-1 metabolite, 12-HHT (IC(50) 41.1+/-1.5microg/ml) with a concomitant rise in 12-lipoxygenase metabolite, 12-HETE in A23187 stimulated human platelets. Conversely, the non-polar hexane extract attenuated (IC(50) 0.36+/-0.12microg/ml) 12-HETE formation with a parallel rise in 12-HHT, thereby displaying a selectivity towards 12-lipoxygenase. Non-polar hexane extract also antagonized the production of 5-lipoxygenase metabolites, i.e., leukotriene B(4) and 5-HETE in the rat neutrophils. Furthermore, ethyl acetate extract inhibited both COX and 5-LOX with a marked decline in the production of 12-HHT (IC(50) 0.08+/-0.002microg/ml) and LTB(4) (IC(50) 0.86+/-0.03microg/ml), respectively. The anti-inflammatory effect of hexane and ethyl acetate extracts was also reflected by the diminution of carrageenan-induced cell infiltration in rat peritoneum. Additionally, plant extracts caused approximately 60% suppression in dextran-induced paw edema implying that they also ameliorate histamine and serotonin release.


CONCLUSIONS
Hexane, ethyl acetate and methanol extracts derived from Aegiceras corniculatum possess significant anti-inflammatory activity via multiple mechanisms and validate their traditional use against inflammation-related diseases.
Roome
Talat
T
International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
Dar
Ahsana
A
Naqvi
Sabira
S
Ali
Shamsher
S
Choudhary
Muhammad Iqbal
MI
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D004195:Disease Models, Animal; D004487:Edema / Q000188:drug therapy / Q000503:physiopathology; D015777:Eicosanoids / Q000096:biosynthesis; D005260:Female; D006801:Humans; D007249:Inflammation / Q000188:drug therapy* / Q000503:physiopathology; D020128:Inhibitory Concentration 50; D008297:Male; D008519:Medicine, Traditional; D051379:Mice; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D010538:Peritonitis / Q000188:drug therapy / Q000503:physiopathology; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D029623:Primulaceae / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D012997:Solvents / Q000737:chemistry
D000893:Anti-Inflammatory Agents; D015777:Eicosanoids; D010936:Plant Extracts; D012997:Solvents