Abstract: The antipyretic activity of ethanol (95%) extracts of Cansjera rheedii J. Gmelin aerial parts of the plant was evaluated against brewer`s yeast-induced pyrexia in rats to assess their antipyretic activity. Rectal temperatures were recorded before and after inducing pyrexia at interval of one hour to five hours. At the same time parallel experiments were run with a standard antipyretic paracetamol (100 mg kg-1) and control (Normal Saline 5 mL kg-1). Ethanol extract of Cansjera rheedii J. Gmelin at dose of 250 mg and 500 mg kg-1 body weight showed the antipyretic activity significantly (p<0.001) compared to that of control.
INTRODUCTION
In traditional medicines, various herbal preparations are being used for treating rise in body temperature. In order to reduce the side effects in modern medicine, efforts are being made to find out suitable herbal drugs. In earlier study, we have reported the antipyretic activity of Toddalia asiatic Linn (Ruckumani et al., 1996). The present study was taken up to evaluate the effect of ethanol extract of aerial parts of the plant Cansjera rheedii J. Gmelin against brewer`s yeast-induced pyrexia.
Cansjera rheedii (Family:Opiliaceae) is a climbing shrub, sometimes armed, commonly known as Kalimanakeerai in Tamil is generally found in India through Malaya to Hong Kong and North Australia (Gamble, 1981; Matthew, 1991). The whole plant of C. rheedii was used for the treatment of post-natal pain (Ravikumar and Vijaya Sankar, 2003). Hepatoprotective effect (Mounnissamy et al., 2008) and cytotoxic effect (Mounnissamy et al., 2007) of the plant were also reported. The tribes of Nilgiris in Tamil Nadu, India using the plant extract for the treatment of intermittent fever (Hosagoudar and Henry, 1996). So, the present study is focused to establish a scientific evidence for its antipyretic activity.
MATERIALS AND METHODS
Materials
The aerial parts of the plant of Cansjera rheedii (Opiliaceae)
were collected in and around Auroville, Puducherry in the month of June
2006 and it was identified and authenticated by Auro Herbarium Sakthi
Botanical Survey Department, Auroville. A voucher specimen has been kept
in our laboratory for future reference (VS-12). The aerial parts of the
plants of Cansjera rheedii were cut into small pieces, shade dried
and powdered. The coarse powder was subjected to continues hot extraction
in a soxhlet by using ethanol (95% v/v). The ethanol was removed by distillation
under reduced pressure. This extract was dissolved in Normal Saline (0.9%
w/v Sodium Chloride) and used for the experiment.
Animals
Adult male Wister rats weighing between 150-175 g were procured from
Adhiparasakthi College of Pharmacy, Melmaruvathur, Chengalpet district,
Tamil Nadu, South India. They were fed on commercial diet (Hindustan Lever
Ltd., Bangalore) and water ad libitum. All the animals acclimatized
for a week before use. The room temperature was maintained at 25 ±
1 °C.
Toxicity Study
The LD50 value of ethanol extract of C. rheedii was
determined by using different doses of the extract according to the up
and down method (Ghosh, 1984).
Antipyretic Activity
Antipyretic activity of drug was measured by the method described
by Smith and Hambourger (1935). The normal body temperature of each rat
was measured rectally by using digital thermometer (Make-SK-1250MC, Sato
Keiryoki Mfg. Co. Ltd., Japan) and recorded. Pyrexia was induced by subcutaneous
(SC) injection of 20% w/v brewer`s yeast suspension (20 mL kg-1)
into the animals back below the nape of the neck region. The site of injection
was massaged in order to spread the suspension beneath the skin. The room
temperature is kept at 25 ± 1 °C. Immediately after yeast administration,
food is withdrawn. Eighteen hours after post challenge, the rise in rectal
temperature of each rat was measured using digital thermometer. The measurement
is repeated after 30 min. Only rats that showed an increase in rectal
temperature of at least 0.7 °C were selected for the study and were
divided into four groups (1-4) comprising each of 6 animals. The Group
1 served as control and received 5 mL kg-1 of normal saline
orally. Groups 2 and 3 treated with ethanol extract of Cansjera rheedii
orally at a dose of 250 and 500 mg kg-1, respectively and
Group 4 were treated with paracetamol (100 mg kg-1 orally)
as reference drug. The rectal temperature was measured by digital thermometer
at an interval of 1, 2, 3, 4 and 5 h, after test extract/reference drug
administration.
Statistical Analysis
The data are expressed as Mean ± SEM and were analyzed statistically
by one-way Analysis of Variance (ANOVA) test between two groups; control
and test groups, followed by student`s t-test. Significant levels were
at p<0.001.
RESULTS AND DISCUSSION
The LD50 study showed that the extract was safe at dose of 2 g kg-1 body weight. The ethanolic extract at a dose of 250 mg and 500 mg kg-1 body weight has shown significant (p<0.001) antipyretic activity, it has shown significant fall in body temperature up to 5 h following its administration. The antipyretic activity started as early as 1 h and the effect was maintained for 5 h. The response was comparable to that of paracetamol a standard antipyretic drug (Table 1).
Fever may be due to infection or one of the sequels of tissue damage,
inflammation, graft rejection, or other disease states. Antipyretic are
agents, which reduce the elevated body temperature. Regulation of body
temperature requires a delicate balance between production and loss of
heat and the hypothalamus regulates the set point at which body temperature
is maintained. In fever this set point elevates and a drug like paracetamol
does not influence body temperature when it is elevated by the
| Table 1: | Effect of ethanolic extract of C. rheedii on yeast-induced pyrexia in rats |
| N = 6 animals in a group, Values are expressed as Mean ± SEM, *p<0.001 vs control, data were analyzed by using one way ANOVA followed by student`s t-test | |
factors such as exercise or increase in ambient temperature (Hullatti and Sharada, 2007). Yeast-induced fever is called pathogenic fever, its etiology includes production of prostaglandins, which set the thermo regulatory center at a lower temperature (Howard, 1993). The results show that ethanolic extract of C. rheedii possesses a significant antipyretic effect in yeast-provoked elevation of body temperature in rats and its effect is comparable to that of paracetamol (standard drug). So, inhibition of prostaglandin synthesis could be the possible mechanism of antipyretic action as that of paracetamol (Chandrashekaran et al., 2002). Also, there are several mediators or multi-processes underlining the pathogenesis of fever. Inhibition of any of these mediators may bring about antipyresis (Akio et al., 1988). From the above study we have concluded the antipyretic activity of the plant Cansjera rheedii J. Gmelin (Opiliaceae). Fractionation of the extract to find out its chemical nature and also to elucidate the probable mechanism of action of antipyretic activity.