- Email: [email protected]
Pharmacological study of Cymbopogon citratus leaves
Journal of Ethnopharmacology, 25 (1989) 103-107 Elsevier Scientific Publishers Ireland Ltd.
PHARMACOLOGICAL
STUDY
OF CYMBOPOGON
D. CARBAJAL, A. CASACO, L. ARRUZAZABALA, Department of Pharmacology Box 6860, Havana (Cuba)
103
CITRATUS
LEAVES
R. GONZALEZ and Z. TOLON
and Toxicology, National
Center for Scientific Research, Post
(Accepted August 26, 1988)
Summary
Cymbopogon citratus leaves are employed by the Cuban population as an antihypertensive and anti-inflammatory folk medicine. A 10% or 20% decoction of leaves was tested using arterial pressure in rats, urine production and carrageenan-induced edema in rats. The decoction showed some intravenously and some weak dose-related hypotensive effects given diuretic and anti-inflammatory effect when given orally. Introduction Lemongrass or Cymbopogon citratus (DC.) Stapf. Fam. Graminaceae (local name cana Santa or cana de limon) is one of the most popular medicinal plants in Cuba as has been demonstrated by a recent national survey (Fuentes and Granda, 1980). In Cuba a decoction of the leaves is reported to have hypotensive, anticatarrhal and antiheumatic properties. In Brazil, the people use this plant for the treatment of nervous and gastrointestinal disturbances (Carlini et al., 1986) and in Angola, Nigeria and India this plant is employed for a variety of different diseases. The aim of the present study is to determine whether or not a decoction of the leaves of this plant has hypotensive and anti-inflammatory effects. Materials and methods
Plant muterials Herbarium sample HAC number 34406 corresponds to the plant material collected near the city of Havana in May and June of the same year and classified by Lit. Victor Fuentes of the Experimental Station of Medicinal Plants. The pharmacological study was conducted with a decoction of the leaves prepared as follows: samples were left for 3 days in an oven at 0378~8741/89/$02.10 01989 Eisevier Scientific Publishers Ireland Ltd. Published and Printed in Ireland
104
37_4O”C, after which 10 g of dry leaves were boiled in 50 or 100 ml of distilled water for 5 min (20 and 10% deco&ions respectively), filtered through muslin with the volume readjusted after filtration.
Blood pressure measurement Fifteen healthy male and female Wistar rats, weighing 180-220g were anesthetized with sodium pentobarbital, 30-40 mg/kg injected intraperitoneally, A tracheotomy was performed and a polyethylene catheter was placed into the right carotid artery for the purpose of measuring systemic arterial pressure (SAP) using a MPU 0.5 transducer and a fourchannel polygraph (Nihon Kohden, model RM-45). Another catheter was inserted into the left jugular vein for injecting the deco&ion. After reaching steady state with respect to the SAP: 1 ml/kg (IV = 5), 2 ml/kg (N = 5), and 3 ml/kg (N = 5) of the 10% decoction was slowly injected (i-v.) at 0.6 ml per min and recordings taken for 50 min or until the SAP returned to control values. Variations in SAP were expressed as percent of control (SAP before injection of deco&ion.)
Measurement
of diuretic
activity
As diuretic compounds are very important for the treatment of hypertension the diuretic activity of the decoction was studied using a modification of the method of Lipschitz et al. (1942). Thirty-two male Wistar stock rats weighing between 180-240 g were fasted and deprived of water for 18 h before the experiment. Four groups of eight rats each received the following treatments. Animals in the control group were each given 25 ml 0.9 NaCl by the oral route. Two groups received 25 ml/kg of the 10 and 20% decoctions respectively. One group was given a suitable oral dose of a reference diuretic (urea, 1.5 g/kg). Animals were put in metabolic cages for 5 h and cumulative diuresis measured. Urinary excretion index was calculated as follows; Urinary
excretion
Anti-inflammatory
Excreted volume index = ~~~~~~~~~ volume x 100.
effect
The method of Winter et al. (1962) was used. Twenty male Wistar rats weighing 100-18Og were fasted and deprived of water overnight (approximately 18 h) prior to the induction of edema with a subpiantar injection of 0.1 ml of 1% carrageenan in physiological saline into the right hind paw. One hour prior to the subplantar injection, the first group of five rats received 3 ml orally (total volume per animal) of saline solution and was designated as a negative control group, another group of equal size received
105
indomethacin 1.5 mg/kg injected subcutaneously and was considered as a positive control group. Control pedal volume was taken immediately before the earrageenan injection (0 h value) and the swelling was measured 5 h later. The mean values of the 5-h reading after deduction of the corresponding O-h values were expressed in percent of the value obtained in control negative animals.
s~tisti~~ arudysis Data were analyzed statistically using Mann-Whitney test. Results
The intravenous injection of single doses of the deco&ion elicited an immediate fall in blood pressure. This effect was transient for l-2 ml/kg doses (Fig. 1) but 3 ml/kg i.v. resulted in a hypotensive effect lasting more than 35 min. Meawrement
of diuretic activity
Table 1 shows that the decoction has a weak diuretic effect, The 10% decoction elicited a 11.1% increase for the urinary excretion index, while the 20% decoction increased the index to 15%. Urea, a weak diuretic substance
Fig. 1. E&z& of Cy~~gon cittatus deco&ion on mean arterial blood pressure in rata. Decoction was administered intravenously at doses of 1 ml/kg, 2 ml&g and 3 ml/kg. Plotted values represent the mean and the S.E.M. of five experiments. Ordinate: percent of arterial blood pressure relative to basal values. Abscissa: time in min.
106 TABLE 1 DIUREI’IC EFFECT OF CYMBOPOGON CITRATUS LEAF DECOCTION IN RATS Oral treatment (25 ml/kg)
Urinary excretion index (W)
Control (saline) Decoction (10%) Decoction (20%) Urea (1.5 g/kg)
2.4 11.1 15.0 67.0
clinically, increased urinary excretion solution by only 2.39%. Anti-inflammatory
by 67% and physiological
saline
effect
The inhibitory effect of the 20% decoction 5 h after injection of carrageenan was 18.6% and this response was significantly less potent than indomethacin which elicited an inhibition of paw edema by 58.6% (Table 2). Discussion
The results obtained with the Cymbo~gon citrates leaf decoction given intravenously in rats suggest that the plant may have some hypotensive potential. The finding that the decoction has a weak diuretic effect also supports the idea that this plant may have some value in the treatment of hypertension. In our experiments we could not elucidate the hypotensive
TABLE 2 EFFECT OF CYMBOPOGGN CZ’ZXATUS LEAF DECOCTION ON CARRAGEENANINDUCED HINDPAW EDEMA IN RATS Treatment
Dose
Hindpaw thickness (mm i S.E.M.)
Edema inhibition (%)
Saline solution
15
4.15 f 0.92
-
15
3.34 zt0.65*
18.6
1.70 * 0.89**
58.6
(ml/kg, P.o.) Decoction 20% (ml/kg, P.o.) Indomethacin
1.5
(mg/kg,s.c.) Significant difference from the corresponding vehicle controls: *P < 0.01, **P < 0.001; N per group = 5.
107
mechanism of this plant but, based on preliminary screening, it did not appear to have either a cardiac depressant effect or a direct relaxant effect on vascular smooth muscle (unpublished results). Further acute and chronic studies will be necessary to elucidate its possible mechanisms of action. The oral anti-inflammatory effect of the decoction was considered too weak to be important in the treatment of rheumatic diseases. Toxicological studies in this laboratory show that the decoction lacks significant toxic, teratogenic and mutagenic effects. These data are in agreement with those ones reported by Souza Formigoni et al. (1986) and support that the decoction is relatively safe when used as a folk medicine. Acknowledgements
We are indebted to Lit. Victor Fuentes, Station of Medicinal Plants, Havana, for collecting and providing us with samples of Cymbopogon citratus. References Carlini, E.A., Contar, J. de P., Silva-Filho, A.R., Da Silveira-Filho, N.G., Frochtengarten, M .L. and Bueno, O.F.A. (1986) Pharmacology of lemongrass (Cymbopogon citratua Stapf.) I: Wecta of teas prepared from the leaves on laboratory Animals. Journal of Ethnophurmacology 17, 37-64. Souza Formigoni, M.L.O., Lodder, H.M., Filho, O.G., Ferreira, T.M .S. and Carlini, E.A. (1986) Pharmacology of lemongrass (Cymbopogon citrates Stapf .). II: Wects of daily two-month administration in male and female rats and in offspring exposed in utero. Joum~l of Ethnophurmacobgy 17,65-74. Fuentes, V. and Granda, M. (1980) Encuesta sobre la utilizacidn de plantas medicinales. VII Seminario Cientffico de1 CNIC, libro de restimenes, - Palacio de las Convenciones, Habana, Cuba, p. 281. Lipschitz, W.L., Hadidian, Z. and Kerpcsar (1942) Bioassay of diuretics. Joumal of Phur?nQcozogy 79,97-110. Winter, C.A., Risley, E.A. and Nuss, G.W. (1962) Carrageenan-induced edema in the hind paw of the rat as an assay for anti-inflammatory drugs. Proceedings of the Society of Experimental Biology and Medicine 111, 544-547.
PHARMACOLOGICAL
STUDY
OF CYMBOPOGON
D. CARBAJAL, A. CASACO, L. ARRUZAZABALA, Department of Pharmacology Box 6860, Havana (Cuba)
103
CITRATUS
LEAVES
R. GONZALEZ and Z. TOLON
and Toxicology, National
Center for Scientific Research, Post
(Accepted August 26, 1988)
Summary
Cymbopogon citratus leaves are employed by the Cuban population as an antihypertensive and anti-inflammatory folk medicine. A 10% or 20% decoction of leaves was tested using arterial pressure in rats, urine production and carrageenan-induced edema in rats. The decoction showed some intravenously and some weak dose-related hypotensive effects given diuretic and anti-inflammatory effect when given orally. Introduction Lemongrass or Cymbopogon citratus (DC.) Stapf. Fam. Graminaceae (local name cana Santa or cana de limon) is one of the most popular medicinal plants in Cuba as has been demonstrated by a recent national survey (Fuentes and Granda, 1980). In Cuba a decoction of the leaves is reported to have hypotensive, anticatarrhal and antiheumatic properties. In Brazil, the people use this plant for the treatment of nervous and gastrointestinal disturbances (Carlini et al., 1986) and in Angola, Nigeria and India this plant is employed for a variety of different diseases. The aim of the present study is to determine whether or not a decoction of the leaves of this plant has hypotensive and anti-inflammatory effects. Materials and methods
Plant muterials Herbarium sample HAC number 34406 corresponds to the plant material collected near the city of Havana in May and June of the same year and classified by Lit. Victor Fuentes of the Experimental Station of Medicinal Plants. The pharmacological study was conducted with a decoction of the leaves prepared as follows: samples were left for 3 days in an oven at 0378~8741/89/$02.10 01989 Eisevier Scientific Publishers Ireland Ltd. Published and Printed in Ireland
104
37_4O”C, after which 10 g of dry leaves were boiled in 50 or 100 ml of distilled water for 5 min (20 and 10% deco&ions respectively), filtered through muslin with the volume readjusted after filtration.
Blood pressure measurement Fifteen healthy male and female Wistar rats, weighing 180-220g were anesthetized with sodium pentobarbital, 30-40 mg/kg injected intraperitoneally, A tracheotomy was performed and a polyethylene catheter was placed into the right carotid artery for the purpose of measuring systemic arterial pressure (SAP) using a MPU 0.5 transducer and a fourchannel polygraph (Nihon Kohden, model RM-45). Another catheter was inserted into the left jugular vein for injecting the deco&ion. After reaching steady state with respect to the SAP: 1 ml/kg (IV = 5), 2 ml/kg (N = 5), and 3 ml/kg (N = 5) of the 10% decoction was slowly injected (i-v.) at 0.6 ml per min and recordings taken for 50 min or until the SAP returned to control values. Variations in SAP were expressed as percent of control (SAP before injection of deco&ion.)
Measurement
of diuretic
activity
As diuretic compounds are very important for the treatment of hypertension the diuretic activity of the decoction was studied using a modification of the method of Lipschitz et al. (1942). Thirty-two male Wistar stock rats weighing between 180-240 g were fasted and deprived of water for 18 h before the experiment. Four groups of eight rats each received the following treatments. Animals in the control group were each given 25 ml 0.9 NaCl by the oral route. Two groups received 25 ml/kg of the 10 and 20% decoctions respectively. One group was given a suitable oral dose of a reference diuretic (urea, 1.5 g/kg). Animals were put in metabolic cages for 5 h and cumulative diuresis measured. Urinary excretion index was calculated as follows; Urinary
excretion
Anti-inflammatory
Excreted volume index = ~~~~~~~~~ volume x 100.
effect
The method of Winter et al. (1962) was used. Twenty male Wistar rats weighing 100-18Og were fasted and deprived of water overnight (approximately 18 h) prior to the induction of edema with a subpiantar injection of 0.1 ml of 1% carrageenan in physiological saline into the right hind paw. One hour prior to the subplantar injection, the first group of five rats received 3 ml orally (total volume per animal) of saline solution and was designated as a negative control group, another group of equal size received
105
indomethacin 1.5 mg/kg injected subcutaneously and was considered as a positive control group. Control pedal volume was taken immediately before the earrageenan injection (0 h value) and the swelling was measured 5 h later. The mean values of the 5-h reading after deduction of the corresponding O-h values were expressed in percent of the value obtained in control negative animals.
s~tisti~~ arudysis Data were analyzed statistically using Mann-Whitney test. Results
The intravenous injection of single doses of the deco&ion elicited an immediate fall in blood pressure. This effect was transient for l-2 ml/kg doses (Fig. 1) but 3 ml/kg i.v. resulted in a hypotensive effect lasting more than 35 min. Meawrement
of diuretic activity
Table 1 shows that the decoction has a weak diuretic effect, The 10% decoction elicited a 11.1% increase for the urinary excretion index, while the 20% decoction increased the index to 15%. Urea, a weak diuretic substance
Fig. 1. E&z& of Cy~~gon cittatus deco&ion on mean arterial blood pressure in rata. Decoction was administered intravenously at doses of 1 ml/kg, 2 ml&g and 3 ml/kg. Plotted values represent the mean and the S.E.M. of five experiments. Ordinate: percent of arterial blood pressure relative to basal values. Abscissa: time in min.
106 TABLE 1 DIUREI’IC EFFECT OF CYMBOPOGON CITRATUS LEAF DECOCTION IN RATS Oral treatment (25 ml/kg)
Urinary excretion index (W)
Control (saline) Decoction (10%) Decoction (20%) Urea (1.5 g/kg)
2.4 11.1 15.0 67.0
clinically, increased urinary excretion solution by only 2.39%. Anti-inflammatory
by 67% and physiological
saline
effect
The inhibitory effect of the 20% decoction 5 h after injection of carrageenan was 18.6% and this response was significantly less potent than indomethacin which elicited an inhibition of paw edema by 58.6% (Table 2). Discussion
The results obtained with the Cymbo~gon citrates leaf decoction given intravenously in rats suggest that the plant may have some hypotensive potential. The finding that the decoction has a weak diuretic effect also supports the idea that this plant may have some value in the treatment of hypertension. In our experiments we could not elucidate the hypotensive
TABLE 2 EFFECT OF CYMBOPOGGN CZ’ZXATUS LEAF DECOCTION ON CARRAGEENANINDUCED HINDPAW EDEMA IN RATS Treatment
Dose
Hindpaw thickness (mm i S.E.M.)
Edema inhibition (%)
Saline solution
15
4.15 f 0.92
-
15
3.34 zt0.65*
18.6
1.70 * 0.89**
58.6
(ml/kg, P.o.) Decoction 20% (ml/kg, P.o.) Indomethacin
1.5
(mg/kg,s.c.) Significant difference from the corresponding vehicle controls: *P < 0.01, **P < 0.001; N per group = 5.
107
mechanism of this plant but, based on preliminary screening, it did not appear to have either a cardiac depressant effect or a direct relaxant effect on vascular smooth muscle (unpublished results). Further acute and chronic studies will be necessary to elucidate its possible mechanisms of action. The oral anti-inflammatory effect of the decoction was considered too weak to be important in the treatment of rheumatic diseases. Toxicological studies in this laboratory show that the decoction lacks significant toxic, teratogenic and mutagenic effects. These data are in agreement with those ones reported by Souza Formigoni et al. (1986) and support that the decoction is relatively safe when used as a folk medicine. Acknowledgements
We are indebted to Lit. Victor Fuentes, Station of Medicinal Plants, Havana, for collecting and providing us with samples of Cymbopogon citratus. References Carlini, E.A., Contar, J. de P., Silva-Filho, A.R., Da Silveira-Filho, N.G., Frochtengarten, M .L. and Bueno, O.F.A. (1986) Pharmacology of lemongrass (Cymbopogon citratua Stapf.) I: Wecta of teas prepared from the leaves on laboratory Animals. Journal of Ethnophurmacology 17, 37-64. Souza Formigoni, M.L.O., Lodder, H.M., Filho, O.G., Ferreira, T.M .S. and Carlini, E.A. (1986) Pharmacology of lemongrass (Cymbopogon citrates Stapf .). II: Wects of daily two-month administration in male and female rats and in offspring exposed in utero. Joum~l of Ethnophurmacobgy 17,65-74. Fuentes, V. and Granda, M. (1980) Encuesta sobre la utilizacidn de plantas medicinales. VII Seminario Cientffico de1 CNIC, libro de restimenes, - Palacio de las Convenciones, Habana, Cuba, p. 281. Lipschitz, W.L., Hadidian, Z. and Kerpcsar (1942) Bioassay of diuretics. Joumal of Phur?nQcozogy 79,97-110. Winter, C.A., Risley, E.A. and Nuss, G.W. (1962) Carrageenan-induced edema in the hind paw of the rat as an assay for anti-inflammatory drugs. Proceedings of the Society of Experimental Biology and Medicine 111, 544-547.