Dual Regulating Effect of
Shaoyao-Gangcao-Tang on COX-2 Expression in Acute and
Resolution Phases of Carrageenin-Induced Pleurisy in
Rats
Gang Chen1,2,3*,
Ming-Liang Tan1,2,3, Xue Gao1,2,3
and Ping Jia4
1Chongqing Key Laboratory of
Nature Medicine Research, 2Chongqing Key
Laboratory of Catalysis and Functional Organic
Molecules, 3Research Center of Medical
Chemistry
and Chemical Biology, Chongqing
Technology and Business University, Chongqing 400067,
4Department of Combination of Chinese and
Western Medicine, the First Affiliated Hospital of
Chongqing University of Medical Sciences, Chongqing
400016, PR China.
*For correspondence:
Email:
gangch_tcm@hotmail.com;
Tel: (+86)-23-6276-8059;
Fax:
(+86)-23-6276-9652
Received: 5 May
2012
Revised accepted:
30 June 2013
Tropical Journal of
Pharmaceutical Research, October 2013;
12(5):
727-733
http://dx.doi.org/10.4314/tjpr.v12i5.10
Abstract
Purpose: To investigate the effects and potential
mechanisms of Shaoyao-Gangcao-Tang (SGT) on acute and
resolution phases of carrageenin-induced pleurisy in
rats.
Methods: To determine the effects of SGT at 2 h, Sprague-Dawley
rats received injection of 0.2 ml of 1 % λ-carrageenin
into the pleural cavity after treatment with 4.0,
13.3 and 40.0 g/kg SGT for three days. At 2 h after
pleurisy induction, exudate volume, total cell number,
prostaglandin E2 (PGE2) production
and cyclooxygenase-2 (COX-2) protein expression were
measured. To determine the effects at 48 h, the rats
were treated with SGT at 24, 36 and 46 h after injection
of λ-carrageenin into the pleural cavity, and the
exudate volume, total cell number, 15-deoxy-Δ12, 14-PGJ2
(15d-PGJ2) production and COX-2 protein
expression were evaluated.
Results: At 2 h after pleurisy induction,
13.3 and 40.0 g/kg SGT
significantly decreased exudate volume by 34 (p < 0.05)
and b 4 0% (p < 0.01), total cell number by 27 (p <
0.05) and 41 % (p < 0.01), PGE2 production by
17 (p < 0.05) and 35 % (p < 0.01), as well as COX-2
protein expression by 21 (p < 0.01) and 43 % (p < 0.01)
compared with control group treated with saline. At 48 h
after pleurisy induction, 13.3 and 40 g/kg SGT also
significantly decreased exudate volume by 36 (p < 0.05)
and 55 % (p < 0.01), as well as total cell number by 31
(p < 0.05) and 43 % (p < 0.01), but markedly increased
15d-PGJ2 production by 26 (p < 0.05) and 51 %
(p < 0.01), as well as COX-2 protein expression by 50 (p
< 0.01) and 100 % (p < 0.01) compared with control
group.
Conclusion: The findings suggest that SGT has dual regulating
effect in acute and resolution phases of inflammation,
involving inhibiting acute inflammation through
down-regulation of pro-inflammatory mediators, and
promoting inflammatory resolution through up-regulation
of pro-resolution mediators.
Keywords: Shaoyao-Gangcao-Tang, Cyclooxygenase-2,
Prostaglandin E2, 15-Deoxy-Δ12, 14-PGJ2,
Inflammation
