Analgesic and anti-inflammatory effects of kolaviron (a Garcinia kola seed extract)

Abstract

Kolaviron is a defatted ethanol extract from the seeds of Garcinia Kola. In the present study, the analgesic and anti-inflammatory properties of Kolaviron is investigated using both thermal and chemical models of pain assessment in mice and rats. Varying doses of Kolaviron were given 30 minutes prior to the induction of abdominal constrictions in mice and the determination of the mean tail immersion duration at water bath temperature of 50.0 ± 10°C in mice. Kolaviron exhibited dose-related anti-nociceptive properties against acetic acid induced abdominal constrictions in mice: at 50mg/kg, it gave 28.92% inhibition (P > 0.05) and at 200mg/kg it gave 55.49% inhibition (P < 0.01). The compound also increased the mean tail immersion duration at water bath temperature of 50.0 ± 1°C in mice.

Full text

Afr. J. Biomed. Res. (2000): Vol 3: 171 - 174
Original article
ANALGESIC AND ANTI-INFLAMMATORY EFFECTS OF
KOLAVIRON (A GARCINIA KOLA SEED EXTRACT)
OLALEYE S.B1*, FAROMBI E. O**, ADEWOYE E. A*, OWOYELE B. V*,
ONASANWO S. A*. AND ELEGBE R.A*
Departments of Physiology* and Biochemistry**, College of Medicine,
University of Ibadan, Ibadan, Nigeria.
Kolaviron is a defatted ethanol extract from the seeds of Garcinia Kola. In the present study, the analgesic and
anti-inflammatory properties of Kolaviron is investigated using both thermal and chemical models of pain
assessment in mice and rats. Varying doses of Kolaviron were given 30 minutes prior to the induction of
abdominal constrictions in mice and the determination of the mean tail immersion duration at water bath
temperature of 50.0 ± 10C in mice. Kolaviron exhibited dose-related anti-nociceptive properties against acetic acid
induced abdominal constrictions in mice: at 50mg/kg, it gave 28.92% inhibition (P > 0.05) and at 200mg/kg it
gave 55.49% inhibition (P < 0.01). The compound also increased the mean tail immersion duration at water bath
temperature of 50.0 ± 10C in mice.
Keywords: Kolaviron, Garcinia kola, analgesic, anti-inflammatory, rats, mice
_____________________________________________________________________________________________________________
Garcinia Kola, Heckel (Gultiferae), a largely cultivated forest tree indigenous to sub-Saharan Africa
has been referred to as a ‘wonder plant’ because almost every part of it has been found to be of
medicinal importance (Hutchinson and Dalziel, 1956). The seed (commonly known as bitter kola,
male kola or false kola) is a masticatory used in traditional hospitality, cultural and social
ceremonies. Extractive of the plant have been traditionally used for ailments such as laryngitis,
liver diseases and cough (Ayensu, 1978). The seeds are used to prevent or relieve colic, cure head
or chest colds and relieve cough (Iwu, 1993). The seed also has anti-inflammatory, antimicrobial,
antidiabetic and antiviral (Iwu, 1986) as well as antiulcer properties (Ibironke et al, 1997).
Kolaviron (Fig. 1) is a defatted ethanol extract from the seeds of Garcinia Kola (GK). It is a
mixture of three compounds - Garcinia biflavonoid GB1, GB2 and Kola flavanone in ratio 2:2:1 (Iwu
et al, 1990, Kubanga, 1987). Kolaviron has been extensively studied for its anti-hepatotoxic effects
(Akintonwa and Essien, 1990; Farombi et al, 2000,) in various experimental models.
In the present study, we report that Kolaviron may be the active principle for the analgesic and
anti-inflammatory activities of G. Kola.
MATERIALS AND METHODS
Plant materials
Seeds of Garcinia Kola were obtained locally in Ibadan, Nigeria in October 1999 and certified by
Prof. Egunyomi in the Department of Botany, University of Ibadan. A voucher specimen is available
in the herbarium of the same institution. 7 kg of Peeled seeds were sliced, pulverised with electric
blender and dried at 40oC in a Gallenkamp drying oven.
Tested material
Kolaviron was isolated according to Iwu et al ( 1990 ) as modified by Farombi et al (2000).
Briefly, the powdered seeds were extracted with light petroleum ether (b.pt 40-60oC) in a soxhlet for
24h. The defatted, dried marc was repacked and extracted with acetone (Me2CO). The extract was
concentrated and diluted twice its volume with water and extracted with ethyl acetate.
The concentrated ethyl acetate fraction gave a yellow solid known as Kolaviron. The extract
(50g) was suspended in 100ml 0.9% NaCl for oral administration to rats. Appropriate dose dilutions
were made with normal saline to provide for a total volume of 0-5ml. 0.5ml of saline was similarly
administered orally to rats.
1 *Author for correspondence: E-mail address: elegbe@skannet.com, Tel: +234(02)810026

African Journal of Biomedical Research (2000): Vol 3/ Olaleye, Farombi, Adewoye, Owoyele & Elegbe
Analgesic and anti-inflammatory effects of Kolaviron
172
R1 R2 R3 R4
GB1 OH H OH H
GB2 OH H OH OH
Kolaflavanone OH H OMe OH
Figure 1
Structure of Kolaviron
Animals:
Adult male Swiss mice (20-25g) and albino rats (100-120g) obtained from the small animal house,
College of medicine, University of Ibadan, Nigeria were used. They were housed in cages at room
temperature with free access to mice cubes (Ladokun Feeds Nig. Limited, Ibadan, Ibadan, Nigeria).
The body weight changes in the rats before and after administration of the extract was monitored
daily.
Analgesic activity
Acetic acid writhing response: Mice were treated orally with the Kolaviron at 50, 100 and
200mg/kg doses. Acetylsalicylic acid (AspegicR) was used as a reference analgesic compound at
70mg/kg dose. Control animals received 0.2ml distilled water. 30 minutes later, the animals were
given 1.2% acetic acid injection. The number of writhing and stretching within the observation
period was recorded. The percentage protection was calculated using the ratio: (control mean –
treated mean) X 100/control mean (Baghelikian et al, 1997).
Tail-flick method: Mice were
treated orally with Kolaviron,
reference drug and vehicle 30
minutes before experiment as
described above. Water was
heated to 50.0 ± 1:00C in a
water bath. By carefully holding
the animal, the tail was
immersed gently in the hot
water bath. The time taken for
the animal to flick its tail out of
the water was recorded. Each
animal served as its own
control, as preliminary
experiments showed that the
procedures involved with
injection of the vehicle lone had
no significant effect on the
response times at 30 minutes.
Anti-inflammatory activity
Edema was induced on the
right foot of rats by sublantar
injection of 0.05ml of solution of
1.5% carrageenan in 0.9%
saline (W/V). The diameter of
the injected paws and
contralateral paws were
measured 1hr, before and 1, 2,
3, 4 and 5 hours after induction
of inflammation using cotton
thread. The edema was
expressed in terms of the
difference between the right and left paws. A reference group of animals were treated with Aspirin
(150mg/kg).
Statistical analysis
All values were expressed as mean ± standard error of mean (SEM) for the acetic acid writhing
tests; statistical comparisons were done using the student’s t-test. For the tail-flick test in mice,
paired t-test was used to compare pain responses before and after treatment with extract, reference
drug or vehicle.
RESULTS
Analgesic activity
Acetic acid writhing response: The effect of Kolaviron on the acetic acid induced abdominal
writhing is shown in Table 1. The result shows that the compound exhibited significant and dose –

African Journal of Biomedical Research (2000): Vol 3/ Olaleye, Farombi, Adewoye, Owoyele & Elegbe
Analgesic and anti-inflammatory effects of Kolaviron
173
0
10
20
30
40
50
60
70
80
% inhibition of oedema
Control KV
(50mg/kg)
KV
(100mg/kg)
KV
(150mg/kg)
ASA
Figure 2.
Maximum inhibition of oedema induced by 1.5%
carra
g
eenan.
(
KV = Kolaviron
,
ASA = As
p
irin
related anti-nociceptive properties against acetic acid induced abdominal constrictions in mice. A
Kolaviron dose of 100mg/kg gave results comparative to 70mg/kg dose of the reference drug,
acetylsalicylic acid.
Table 1
Effect of Kolaviron on acetic acid writhing response in mice.
Treatment No of writhing
(Mean ± SEM)
Percentage protection
Vehicle (Distilled water) 30.60 ± 4.5 ----
Kolaviron (50mg/kg) 26.52 ± 4.8N.S 13.33
Kolaviron (100mg/kg) 21.75 ± 3.11* 28.92
Kolaviron (200mg/kg) 14.20 ± 2.50* 53.59
Aspirin (70mg/kg) 13.62 ± 2.80* 55.49
N.S= Not significant, *P<0.05 (c.f. vehicle), n= 10.
Table 2
Thermal pain perception (Tail immersion in 50 ± 10C hot water) in the presence or absence of Kolaviron
and acetylsalicylic acid.
Reaction times (seconds) (Mean ± SEM)
. Post-treatment
Treatment
Pre-
treatment 30min 60min
Vehicle (Distilled water) 7.35 ± 0.13 7.95 ± 2.19N.S 8.06 ± 2.15
Kolaviron (50mg/kg) 7.40 ± 0.18 9.63 ± 0.50*
(21.13
10.12 ± 1.10
(25.56)
Kolaviron (100mg/kg) 7.85 ± 0.13 11.52 ± 1.66**
(44.91)
10.97 ± 1.36
(36.10)
Kolaviron (200mg/kg) 7.55 ± 0.17 16.95 ± 1.32**
(113.21)
16.85 ± 0.93
(109.06)
Aspirin (70mg/kg) 7.95 ± 0.26 18.72 ± 1.65**
(135.47)
20.32 ± 1.15
(152.11
*P<0.05, **P<0.001, N.S= Not Significant, (c.f. Vehicle, paired t-test, n=15
Values in parenthesis represent percentage protection
Latency of tail immersion in mice: The
mean tail immersion in hot water bath (55
± 10C) one hour before and 30 minutes
after oral administration of varying doses
of Kolaviron are shown in Table 2.
Treatment with the vehicle did not have
any significant effect on the latency of tail
immersion. Kolaviron, at all doses tested,
showed significant and dose-related
increases in tail immersion duration.
Anti-inflammatory effect
The anti-inflammatory potencies of acetyl
salicylic acid and Kolaviron are compared
in figure 1. Kolaviron showed relatively
good anti-inflammatory activity when
compared with aspirin. The maximum
inhibition of edema attained in the rats
pre-treated with 100mg/kg kolaviron
(59.52% ± 4.65) is not significantly
different from that given by 150mg/kg Aspirin. (62.05% ± 3.75). The inhibition produced by
Kolaviron dose of 150mg/kg (72.40% ± 3.35) was significantly higher than that of aspirin.

African Journal of Biomedical Research (2000): Vol 3/ Olaleye, Farombi, Adewoye, Owoyele & Elegbe
Analgesic and anti-inflammatory effects of Kolaviron
174
DISCUSSION
In this study, the analgesic and anti-inflammatory properties of Kolaviron, a defatted seed
extract of Garcinia kola (bitter kola), was investigated in mice. We have shown here that Kolaviron
exhibited a weak analgesic but very strong anti-inflammatory activities when compared to a
standard reference drug, acetyl salicylic acid. There appears to be a fair degree of agreement
between the thermo- and chemonociceptive assays used in the present study. There is no generally
accepted paradigm for pain assessment in either human or animal experiments. It is therefore
essential to employ two or more of this method in a single study before a definite conclusion can be
made on the action of any agent affecting pain responses.
The activity of Kolaviron may not be unrelated to the presence of the biflavonoid group. The
biflavanones of Garcinia kola are pharmacologically active with several pharmakokinetic
advantages over simple monomeric flavonoids. For instance, the biflavonoids have been shown to
survive first pass metabolism which inactivates most flavonoids and they have been proved to
possess very high therapeutic potentials (Iwu, 1986). Furthermore, many plants containing
flavonoids have been shown to have diuretic, laxative, antispasmodic, anti-hypertensive and anti-
flammatory actions (Okuda, 1962). The traditional use of G. kola in the traditional management of
inflammatory conditions in hepatic and respiratory systems is thus justified.
Further studies aimed at identifying the component of Kolaviron responsible for the observed
anti-inflammatory activity is in progress.
REFERENCES
Baghelikian B; Lanhers M.C, Fleurentin J, Ollivier
E, Maillard C, Balansard G and Mortier F (1997).
An analytical study of the anti-inflammatory and
analgesic effects of Harpagophytum procumbers and
Harpagophytum zeyeri. Planta Medica 63:171 – 176.
Hutchinson J., Dalziel J.M. (1956). Flora of West
Tropical Africa. 2nd ed. H.M.S.O; London, Vol 11, pp.
295.
Iwu M.M (1993) Pharmacognostical profile of
selected medicinal plants. In: Handbook of African
Medicinal Plants. Pp 183. CRC Press, Boca Raton,
Florida.
Ayensu E.S. (1978). Medicinal Plants of West Africa
Reference Publication Inc; Algonac, MI. pp. 162.
Iwu M.M. (1986): In Plant flavonoids in Biology and
Medicine, V. Cody, E. Middleton and J.B. Harbone
eds. Ala R. Liss. New York p 485
Braide V. B. (1991). Inhibition of drug metabolism
by flavonoid extract (Kolaviron) of Garcinia kola seeds
in the rats. Phytotherapy research 5: 38 - 40
Farombi E.O, Tahntenyg D.G., Agboola A.O.,
Nwankwo J.O. and Emerole G.O. (2000) Food and
Chem Toxicol. 38 (6): 535 – 541.
Akintonwa A. and Essien A.R (1990). Protective
effects of Garcinia kola seed extract agaist
paracetamol-induced hepatotoxicity in rats. Journal
of Ethnopharmacology 29: 207 - 211.
Okuda T (1962) Flavonoids. In. Chemistry of Organic
Natural Products. ed. by h. Mitsuhashi, O. Tanaka.
S. Nazoe and M. Nagai pp. 219 - 228. Nankodo,
Tokyo.
Ibironke G.F., Olaleye S.B., Balogun O. and Aremu
D.A. (1997). Antiulcerogenic effects of diets
containing seeds of Garcinia kola (Heckel)
Phytotherapy Research 11, 312 - 313.
Iwu M.M., Igboko O.A., Elekwa O.K and Tempesta
M.S. (1990): Prevention of thioacetamide-induced
hepatotoxicity by biflavanones of Garcinia kola.
Phytotherapy Research 4; 157 - 159.
Received: 18th February 2000
Accepted in final form: 4th July 2000