Analgesic, anti-inflammatory and antiemetic activities of Cleome scaposa DC

Abstract

Cleome scaposa DC., has long been used in traditional herbal medicine for the treatment
of pain and inflammation. The present investigation is an attempt to evaluate
antiemetic, analgesic and anti-inflammatory activities of Cleome scaposa leaves
methanolic extract by using chick emesis model (oral treatment), analgesy meter
test (intraperitoneal treatment) in rats and carrageenan induced rat paw edema (oral
treatment) respectively. The antiemetic activity (150 mg/kg b.w., of extract) was
carried out by using chlopromamize (150mg/kg) as standard antiemetic drug. The
analgesic activity (250 mg/kg b.w., of extract) was performed by using diclofenac
sodium (50mg/kg) as standard analgesic drug whereas, anti-inflammatory activity
(500mg/kg b.w., of extract) was done and indomethacin (10mg/kg) was taken as
standard anti-inflammatory drug. The results showed significant antiemetic, analgesic
and anti-inflammatory effects

Full text

Phytopharmacology 2013, 4(1), 106-113 Shaheen et al.
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Analgesic, anti-inflammatory and antiemetic activities of Cleome
scaposa DC.
Najma Shaheen, Salman Ahmed, Iqbal Azhar, Muhammad Mohtasheemul Hasan*
Department of Pharmacognosy, Faculty of Pharmacy, University of Karachi, Karachi – 75270, Pakistan
*Corresponding author: phm.hasan@gmail.com ;Tel:(+9221) 99261300-7 Ext. 2400
Received: 3 August 2012, Revised: 24 September 2012, Accepted: 26 September 2012
Abstract
Cleome scaposa DC., has long been used in traditional herbal medicine for the tre-
atment of pain and inflammation. The present investigation is an attempt to evalua-
te antiemetic, analgesic and anti-inflammatory activities of Cleome scaposa leaves
methanolic extract by using chick emesis model (oral treatment), analgesy meter
test (intraperitoneal treatment) in rats and carrageenan induced rat paw edema (oral
treatment) respectively. The antiemetic activity (150 mg/kg b.w., of extract) was
carried out by using chlopromamize (150mg/kg) as standard antiemetic drug. The
analgesic activity (250 mg/kg b.w., of extract) was performed by using diclofenac
sodium (50mg/kg) as standard analgesic drug whereas, anti-inflammatory activity
(500mg/kg b.w., of extract) was done and indomethacin (10mg/kg) was taken as
standard anti-inflammatory drug. The results showed significant antiemetic, analg-
esic and anti-inflammatory effects.
Keywords: Cleome scaposa ; antiemetic; analgesic; anti-inflammatory
Introduction
Plant derived substances are continue to have a place in the process of drug disco-
very, especially in the development of new analgesic and anti-inflammatory drugs. They not
only help in the development of new analgesic and anti-inflammatory drugs but also greatly
contributed to understand complex pathway of pain transmission, receptor types and endo-
genous ligands involved in pain transmission. Isolation of morphine (Papver somniferum),
tetrahydrocannabinol (Cannabis sativa), Capsaicin (Capsicum species), Salicylic acid (Salix
species) prove the involvement of opioid (µ,δ and ҡ), cannabinoid (CB1 and CB2), vanilloid
receptors and cycloooxygenase enzyme respectively in pain and inflammation. The search
for new naturally occurring analgesic and anti-inflammatory compounds is intensifying
because of their effectiveness, lack of serious side effects and providing significant leads in
the development of more effective synthetic molecules (Calixto etal.,2000). Search for anal-
gesic and anti-inflammatory secondary metabolites proved alkaloids, flavonoids, steroids and
terpenoids as analgesic (Calixto etal.,2000) whereas alkaloids, fatty acids, polyphenolics (fla-

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vonoids, lignans, phloroglucinols, quinines, phenylpropanoids, stilbenes and diarylheptanoi-
ds), steroids, terpenoids (Gautam & Jachak,2009; Agnihotri etal.,2010), saponins and polysa-
ccharides (Agnihotri etal.,2010) behave as anti-inflammatory agents. Similarly, diarylheptanoids
(Yang et al., 1999c,d ; Shin et al.,2002; Yang etal., 2002), flavonoids (Kinoshita et al., 1996;
Yang et al. 1999a,b,d; Shin et al.,2002), glucosides (Yang et al., 1999b), lignans (Kinoshi-ta et
al.,1996; Yang etal., 1999b), monoterpenes (Kinoshita et al.,1996), sesquiterpenes (Kinoshi-ta
etal.,1996; Yang et al., 1999d), triterpenes (Kinoshita et al.,1996; Eda et al.,2005), phenylpro-
panoids (Kawai et al.,1994; Kinoshita etal.,1996), polysaccharides (Maki et al., 1987) and sterols
(Yang etal., 1999; Shin etal.,2002) are reported as active anti-emetic principles.
Cleome scaposa DC., (Family: Capparaceae) is found as a common weed all over the
plains of Arabia, Egypt, India, Pakistan and throughout the tropics of the world (Ali, 1973). It
is an annual, 10-30 cm tall, Leaves simple. Flowers 3-4 mm across, actinomorphic, white tur-
ning yellowish rarely pinkish; Capsule linear, 20-30 mm long. Seeds about 0.6 mm in diam.,
brown-black. Cleome species have been used in different abdominal complaints (Atiqur etal.,
2004; Khan, 2009) and given in pain and inflammation (Qureshi etal., 2010). Trinortrite-
rpenoid dilactone (brachycarpone), deacetoxybrachycarpone, cabralealactone, ursolic acid
are reported from Cleome species (Viqaruddin & Khisal, 1987).The chemical structure of
these compounds are mention in Figure 1. Cleome scaposa DC., has been used traditionally
as analgesic, antipyretic and anti-inflammatory agent ( Hameed et al., 2011).
O
O
O
O
O
O
O
O
O
O
O
OAc
H
COOH
HO
H
Cabralealactone Brachycarpone
Deacetoxybrachycarpone Ursolic Acid
Figure 1. Chemical structure of constituents isolated from Cleome species.

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Materials and Methods
Plant material
Leaves of Cleome scaposa DC., were collected by Mr. Arshad Gohar from University
of Karachi in July 2011 identified by a taxonomist and a voucher specimen (G.H.No. 86450)
was deposited in the herbarium of Department of Botany, University of Karachi.
Extraction
Leaves were dried in shade at room temperature for 7 days then soaked in methanol
for 5 days at room temperature and filtered through filter paper. Methanolic extract was obt-
ained by using rotary evaporator under reduce pressure at 40oC.
Animals
Young male chicks, 4 days old (32-52 g) and Whistar albino rats (150-200g) of both
sexes were obtained from Big-bird Poultry Breeders (Pvt) Ltd., and Animal house of Aga
Khan University, Karachi, Pakistan respectively. They were housed in plastic cages with saw
dust as beddings under temperature 25 ± 2°C; 12 h/12 h light-dark cycle and given food and
water ad libitum. The animals were treated complying with the international standards for
dealing the experimental animals duly approved by the legal bodies of the University of Kar-
achi. Chicks (for antiemetic activity) and rats (for analgesic and anti-inflammatory activities)
were randomly divided into three groups. The groups of animals were transferred in different
cages and marked with their identification. Permission and approval from animal studies we-
re obtained from Board of Advanced Studies and Research, University of Karachi [BASR.
Res. No.25 (15)-2007].
Chemicals used
Copper (II) sulfate pentahydrate (copper sulfate) was purchased from Scharlau Chem-
ie S.A. Barcelona, Spain. 3-(2-chloro-10H-phenothiazin-10-yl)-N,N-dimethyl-propan-1-ami-
ne (chlorpromazine) was purchased from ICN, USA. DMSO, Tween 80 and methanol were
purchased from Merck, Darmstadt, Germany. Indomethacin), Carrageenan and Diclofenac
sodium were purchased from Sigma-Aldrich Corporation.
Analgesic activity
Analgesic activity was determined by using Analgesy meter test (Randall & Selitto ,
1957). The group of rats were treated intraperitoneally with normal saline, Cleome scaposa
DC., leaves extract (250mg/kg each) and standard (diclofenac sodium 50mg/kg). The left
hind paw of rat was placed on a plinth under a cone-shaped pusher of the Ugo Basile analge-
sia meter (No. 7200). It generates a linearly increasing mechanical force or pressure on hind
paw. As the applied pressure increases, it gets to a point where the animal struggles to free its
paw. The strength at which each rat withdrew its paw was recorded and considered as indica-
tive of pain. The reaction strength of each rat was determined before and at 1, 2 and 3hrs
after treatment with standard drug or plant extract. Stimulus was terminated and force thres-

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hold read in grams taken as soon as nociceptive response was elicited by the rats. Inhibition
of pain (%) or pain threshold was calculated as follows:
Pain threshold = (Treated mean – Control mean/ Control mean) x 100.
Anti-Inflammatory activity
The anti-inflammatory activity of methanol extract of Cleome scaposa DC., leaves
(500 mg/kg) was evaluated following the protocols of Winter and co-workers (1962) with
slight modifications (Rimbau etal., 1996). Oedema was induced by subplantar injection of
carrageenan (0.1 ml of 1% solution in 0.9% saline solution) into the left hind paws. Paw
volume was measured after 3rd hour of carrageenan treatment by means of volume display-
cement methods using the Ugo Basile plethysmometer (No.7140). The difference between
initial and after treatment paw volumes indicated the degree of inflammation. Oedema was
expressed as a percent increase in paw volume due to carrageenan administration referred to
the noninjected paw. The average increase in paw volume of each group was calculated and
compared with the control (saline) and the indomethacin (10 mg/kg orally) groups. Oedema
inhibitory activity was calculated according to the following formula:
% reduction of edema = (C - T / C) x 100
Where: C = % swelling of control group (untreated) and T = % swelling of treated group.
Antiemetic activity
The anti emetic activity was evaluated by using chick emesis model (Akita etal.,
1998). Each chick was placed in a large beaker and left to settle for 10 minutes. The metha-
nol extract of Cleome scaposa DC., leaves was prepared as a dose of 150 mg/kg body weight
in a volume of 10 ml/kg in 0.9% saline containing 5% DMSO and 1% Tween 80. The dose
was administered abdominally. The control group received only saline 0.9%. After 10 minu-
tes, copper sulfate was administered orally at 50 mg/kg b.w., and the number of retches was
observed during the next 10 minutes. Chlorpromazine was used as a standard antiemetic drug
(150 mg/kg body weight). The percent inhibition was calculated by the following formula:
Inhibition (%) = (A-B/A) x 100
Where, A = Frequency of retching in control group; and B = Frequency of retching in
test group
Statistical analysis
Antiemetic, analgesic and anti-inflammatory activities were expressed as mean ± sta-
ndard error of mean. The statistical significance of the difference was determined by an unp-
aired Student's t-test.

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Table 1. Analgesic activity of Cleome scaposa leaves extract.
Pain threshold ± S.E.M (% inhibition of pain)
After Drug Administration Groups Before Drug
administration 1 hr 2 hr 3 hr
% Inhibition average
Control 36.66±1.7 39.16±2.3 40.83±2.7 35.3±2.3 ---
DS
50 mg/kg i.p. 53.3±2.0 81.34±2.7 *
(26.86)
102.2±2.3**
(40.40)
70.4±3.2**
(16.27) 27.84
CS
250 mg/kg i.p. 45.8±2.7 57.9±2.3**
(32.36)
82.5±5.5**
(50.50)
70±4.9**
(49.57) 44.14
DS = Diclofenac sodium , CS= Cleome scaposa , i.p. = intraperitoneal treatment, Values are mean ± SEM, N=6 for each
group, *P<0.05 &**P<0.005 vs. control showing significant and most significant values using unpaired Student’s t-test.
Results and Discussion
The intraperitoneal administration of Cleome scaposa DC., leaves extract (250
mg/kg) showed significant antinociceptive effect against mechanical pain (Table 1).The ana-
lgesia-meter test is a useful method in elucidating centrally mediated antinociceptive respon-
ses. The crude extract increased nociceptive threshold of rat further strengthening the eviden-
ce of centrally mediated antinociceptive activity (Nkeh et al., 2002). The methanol extract of
Cleome scaposa at the dose 250 mg/kg,i.p., significantly reduced the animal sensitivity to
pain induced by pressure. The % average inhibition from pain was found to be 27.84 of
diclofenac sodium and 44.14 of Cleome scaposa. The central protecting effect of Cleome
scaposa leaves extract was comparable to diclofenac sodium. In this model of pain, Cleome
scaposa leaves extract significantly increased the ability of animals to withstand pressure-
induced pain indicating a more central acting mechanism of the extract.
At the dose of 500 mg/kg the Cleome scaposa DC leaves extract showed maximum
inhibition of the oedema (69.16 %) as compared to control. The oedema inhibition by Indom-
ethacin 10 mg/kg p.o. was tested as 44.67% (Table 2). Oedema development in carrageenan-
induced paw oedema model in rats is represented by two phases (Vinegar et al., 1969). The
first phase occurs within an hour of carrageenan injection and is partly due to the trauma of
injection and also due to release of histamine and serotonin (Crunkhon & Meacock, 1971).
Oedema induced by carrageenan after 3rd hour of injection indicates the second phase of
applying acute inflammatory model which is mediated by prostaglandins, the cycloxygenase
products and lipoxygenase products (Vinegar et al., 1969). Non-steroidal anti-inflammatory
agents inhibit cyclooxygenase (COX-2) enzymes involved in prostaglandin synthesis (Robin-
son, 1997; Kulkarni et al., 2000). Based on these reports it is possible that the inhibitory
effect of the Cleome scaposa DC leaves extract on carrageenan-induced inflammation in rats
could be due to inhibition of cyclooxygenase leading to inhibition of prostaglandin synthesis.
Although the cyclooxygenase and lipoxygenase pathways are both involved in the inflamm-
Table 2. Anti-inflammatory activity of Cleome scaposa leaves extract.
Groups Mean paw oedema (ml) ± S.E.M at 3rd hour % inhibition of inflammation
Control 78.8±9.7 ------
Std. (IND) 10 mg/kg p.o. 43.6±1.7 44.67*
CS 500 mg/kg p.o. 24.3±0.3 69.16*
IND= Indomethacin, CS= Cleome scaposa, N = 6 for each group, p.o. = per oral, S.E.M.= Standard Error of Mean,*
P<0.01vs. control showing significant values using unpaired Student’s t-test.

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Table 3. Antiemetic activity of Cleome scaposa leaves extract.
Groups Mean number of Retches±S.E.M Inhibition (%) of emesis
Control 68.12±3.88 -----
Std. (CPZ) 150 mg/kg p.o. 45.0±0.28* 33.94
CS 150 mg/kg p.o. 34.1±2.16** 49.94
CPZ= Chlorpromazine, CS= Cleome scaposa, N = 6 for each group, p.o.= per oral, S.E.M.= Standard Error of Mean, *P
<0.1 and **P<0.005 vs. control showing significant and most significant values values using unpaired Student’s t-test.
atory process, inhibitors of cyclooxygenase are more effective in inhibiting carrageenan-
induced inflammation than lipoxygenase inhibitors (Flower et al., 1980). In our experiment,
rats pre-treated with Cleome scaposa DC leaves extract showed a significant oedema inhib-
itory response after 3rd hour following carrageenan injection. This result suggests that
Cleome scaposa DC leaves extract may act by suppressing the later phase of the inflamm-
atory process by the inhibition of cyclooxygenase. So, inhibition of carrageenan induced paw
oedema by the crude extract could be due to its inhibitory activity on the prostaglandins.
Cleome scaposa DC., leaves extract in dose of 150 mg/kg body weight reduced the
numbers of retches by 49.94% (Table 3). The group of chicks treated with chlorpromazine
had 45 retches compared to the 68 retches of the control group, thus chlorpromazine reduced
the retches by 33.94%. From the results it is clear that the extract has antiemetic potential
and is comparable with standard chlorpromazine. Although the result is significant but the
mode of action is not known. However, as the oral copper sulphate induces emesis by perip-
heral action and peripheral 5- HT4 plays an important role in copper sulfate induced emesis
(Bhandari et al., 1991; Fukui et al., 1994), the extract was able to effectively prevent its
effect, it could be implied that the extract has a peripheral antiemetic action.
As mentioned earlier that triterpenoids such as brachycarpone, deacetoxybrachycar-
pone, cabralealactone and ursolic acid are reported from Cleome species (Viqaruddin &
Khisal, 1987). Triterpenoids possess analgesic (Biswas etal.,2009) anti-inflammatory (Singh
etal.,2006; Gautam & Jachak,2009) and antiemetic (Kinoshita etal.,1996) properties. Analge-
sic and anti-inflammatory activities of ursolic acid also has been proven (Vasconcelosa etal.,
2006).So, if triterpenoids are present in the studied extract it may be implied that the obse-
rved analgesic, anti-inflammatory and antiemetic activities may be due to the presence of
these triterpenoids.
It may be said that Cleome scaposa DC., leaves extract has analgesic, anti-iflamm-
atory and antiemetic effects. These results support the traditional use of Cleome scaposa in
some painful conditions and gastro intestinal complaints. Further investigations are required
to establish responsible analgesic, anti-inflammatory and antiemetic compound(s) and elucid-
ate exact mechanism of action.
Conflict of interest
There is no conflict of interest associated with the authors of this paper.

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