Effect of Tamarindus indica fruits on blood pressure and lipid-profile in human model: an in vivo approach

Abstract

Fruits of Tamarindus indica were evaluated for their effects on lipid profile, systolic and diastolic blood pressure and body weight in human subjects. Dried and pulverized pulp of T. indica fruits, at a dose of 15 mg/kg body weight, was found to reduce total cholesterol level (p = 0.031) and LDL-cholesterol level (p = 0.004) to a significant extent. Though the fruits exerted no conspicuous effect on body weight and systolic blood pressure, it significantly reduced the diastolic pressure as confirmed by independent sample t-test at 5% significance level.

Full text

Pak. J. Pharm. Sci., 2006, Vol.19(2), 125-129
125
ORIGINAL ARTICLE
EFFECT OF TAMARINDUS INDICA FRUITS ON BLOOD PRESSURE
AND LIPID-PROFILE IN HUMAN MODEL: AN IN VIVO APPROACH
A.S.M. MARUF IFTEKHAR*, ISRAT RAYHAN**, MOHIUDDIN ABDUL QUADIR,
SHARIF AKHTERUZZAMAN*** AND ABUL HASNAT
Faculty of Pharmacy, University of Dhaka, Dhaka-1000, Bangladesh
*Department of Pharmacy, University of Asia Pacific, Dhanmondi, Dhaka, Bangladesh
**ISRT, Dhaka University, Dhaka-1000, Bangladesh
***Department of Biochemistry and molecular Biology, Dhaka University, Dhaka-1000, Bangladesh
ABSTRACT
Fruits of Tamarindus indica were evaluated for their effects on lipid profile, systolic and diastolic blood pressure
and body weight in human subjects. Dried and pulverized pulp of T. indica fruits, at a dose of 15 mg/kg body
weight, was found to reduce total cholesterol level (p = 0.031) and LDL-cholesterol level (p = 0.004) to a significant
extent. Though the fruits exerted no conspicuous effect on body weight and systolic blood pressure, it significantly
reduced the diastolic pressure as confirmed by independent sample t-test at 5% significance level.
Keywords: Tamarindus indica, blood pressure, lipid profile humans.
INTRODUCTION
Total lipid profile of an individual is a contributive principle
resulting from blood cholesterol along with its associated
varieties of lipoproteins i.e., high-density lipoproteins
(HDL, or α-lipoproteins), low-density lipoproteins (LDL, or
β-lipoproteins), Very-low density lipoproteins (VLDL, or
pre-β-lipoproteins) and Triglycerides. Disposition of blood
pressure and coronary heart disease has been found to be in
strong correlation with lipid profile particularly with blood
cholesterol level (Cotran, 1999). Natural product medicines
from plant sources of wide diversity have long been used
effectively in the treatment of blood pressure and higher
lipid level (Anderson et al., 1995; Koscielny et al., 1999;
Anderson et al., 2000; Castano et al., 2001; Debourdeau et
al., 2001; Quiles et al., 2002; Ros et al., 2004; Delaney et
al., 2003).
Tamarindus indica L is a plant growing and cultivated
widely in Bangladesh. The fruit is locally known as Tentul
(Tamarind). Fruits of T. indica L are used in Bangladeshi
folk medicine for their carminative, laxative and digestive
properties. Leaves and seeds are astringent while tender
leaves and flowers posses antibilious properties. Bark is
reported to be prescribed in asthma, amenorrhoea and as
febrifuge (Yusuf et al., 1994). T. indica fruits have been
investigated for its cholesterol-lowering effect on rat,
however no similar work has been reported in human
model.
In this research, the effect of dried and pulverized pulp of T.
indica fruit (oral administration) on serum cholesterol,
HDL- and LDL-cholesterol and triglyerides have been
studied in human models to look for their possible
cholesterol lowering activity. In addition, since cholesterol
level is intimately associated with body weight and blood
pressure, the effect of fruit pulp has also been evaluated on
these two parameters.
EXPERIMENTAL
Plant material
Fruits of T. indica were locally collected from cultivated
plants in Dhaka (Bangladesh). The plant was identified by
Bangladesh National Herbarium, where voucher specimens
have been deposited for future reference.
Tested material
Dried and pulverized pulp of T. indica fruit.
Study subjects and protocol
Twenty male and ten female volunteers (n=30) were chosen
randomly within the age limit of 25-49. The physical and
pathological histories of these volunteers were recorded and
normal diet was provided. Volunteers did not take any
medicine for two months prior to conduction of study.
National protocols for utilizing human subjects were closely
adhered. Dried and pulverized pulp of T. indica fruit was
orally administered at a dose of 15 mg/kg body weight to
each of the experimental volunteers (n=15) twice a day for 4
weeks. Body weight, systolic and diastolic blood pressure
were recorded with standardized procedure after the oral
Corresponding author: E-mail: ahasnat99@yahoo.com , +88152432671

Effect of Tamarindus indica fruits on blood pressure
Pak. J. Pharm. Sci., 2006, Vol.19(2), 125-129
126
administration. In control group (n=15) lactose was
provided at a dose 15 mg/kg body weight for four weeks to
each volunteer and all parameters as mentioned earlier were
determined. Ethical permission was obtained from
Bangladesh Medical Research Council (BMRC).
Lipid profile analysis
Venous blood was collected from the volunteers and
allowed to clot. It was then centrifuged for 15 min at 3,000
rpm. Clear serum was then separated from the cells and
stored at −80
o
C if not analyzed immediately.
The serum samples were assayed for total cholesterol
(Trinder, 1969; Richmond, 1973; Roeschlau et al., 1974)
and triglyceride (Trinder, 1969; Nagele et al., 1984) was
determined by enzymatic method using a commercially
available reagent kit (Randox laboratories Ltd., United
Kingdom). In order to determine the HDL-cholesterol, low
density lipoproteins (LDL and VLDL) and chylomicrone
fractions were precipitated quantitatively by the addition of
phosphotungstic acid in the serum in presence of
magnesium ion (Lopes-Virella et al., 1977). After
precipitation sample was centrifuged. Cholesterol
concentration in the supernatant fraction was determined by
using cholesterol kit. Serum LDL cholesterol was
determined according to previously reported methods
(Wieland et al., 1999). The low-density lipoproteins (LDL)
were precipitated by heparin at their isoelectric point (pH
Table 1: Effect of tamarind on body weight, blood pressure and lipid profile
Experimental volunteers (n=15) Control volunteer (n=15)
Mean ± SD Mean ± SD
P-value
Body weight (kg) 60.1667 ± 10.46180 60.4375 ± 10.80591 0.257
Systolic blood pressure, mm (Hg) 111.3333 ± 10.95313 112.5417 ± 11.13545 0.489
Diastolic blood pressure, mm (Hg) 73.2083 ± 9.20765 76.667 ±9.49905 0.013
Total cholesterol (mg/dl) 118.4583 ± 27.90664 131.8333 ± 24.98985 0.031
HDL-cholesterol (mg/dl) 29.1563 ± 7.00972 31.7688 ± 8.39046 0.194
LDL-cholesterol (mg/dl) 57.3646 ± 25.33150 78.1979 ± 26.47688 0.004
Triglycerides (mg/dl) 157.9167 ± 68.29216 109.3333 ± 77.62321 0.016
0
20
40
60
80
100
120
140
160
180
Body weight
(kg)
SBP (mm Hg) DBP (mm
Hg)
Total
cholesterol
(mg/dl)
HDL-
cholesterol
(mg/dl)
LDL-
cholesterol
(mg/dl)
T riglycerides
(mg/dl)
Before After
Fig. 1: Graphical presentation of effect of fruits of T. indica on body weight, blood pressure, total cholesterol, HDL-
cholesterol, LDL-cholesterol and triglyceride.

A.S.M. Maruf Iftekhar et al.
Pak. J. Pharm. Sci., 2006, Vol.19(2), 125-129
127
5.12) and centrifuged for 15 minutes at ~ 3000 rpm. The
cholesterol concentration of supernatant was determined by
using total cholesterol kit.
Statistical analysis
Statistical analysis was performed using SPSS windows
version 11.5. All values are expressed as mean ± SD. For all
generated data statistical differences were assessed by
independent sample t-test. P values of ≤ 0.05 were
considered significant. The same experiment was repeated
for control group (N=15) with placebo and all the
parameters were recorded as stated before.
RESULT
This study was attempted to identify the effect of fruits of T.
indica on body weight, systolic and diastolic blood pressure,
total cholesterol, HDL-cholesterol, LDL-cholesterol and
triglycerides. The parameters were measured after the oral
administration of tamarind. Table 1 presents the data of
body weight, systolic and diastolic blood pressure, total
cholesterol, HDL-cholesterol, LDL-cholesterol and
triglycerides. Mean, standard deviation and P-values also for
independent sample t-test at 5% significance level are
included in this table 1. The average body weight of 15
control volunteers was 60.43 kg after taking placebo and
60.16 kg for experimental group after taking tamarind. P-
value for independent sample t-test was >0.05, indicates that
there is no significant change in body weight after
administration of tamarind to the volunteers. No significant
change was also observed in systolic blood pressure after
administration of tamarind (P>0.05). However, for diastolic
blood pressure, P value for independent sample t-test was
found to be <0.05 which indicates a significant effect of
tamarind on diastolic blood pressure. Average diastolic
blood pressure was 76.66 mm (Hg) for control group and
73.20 mm (Hg) for experimental group (table 1).
Total blood cholesterol level was significantly reduced from
131.83 mg /dl to 118.45 mg/dl after administration of
tamarind (P<0.05). Again, tamarind significantly lowered
the LDL-cholesterol from 77.98 mg/dl to 57.36 mg/dl with a
P-value of 0.016. Tamarind was found to impart no
significant effect on HDL cholesterol level at 95%
confidence level (P>0.05). However, it was observed that,
after oral administration of tamarind, there was a significant
rise in triglyceride level in blood from 109.33 to 157.91
mg/dl (table 1). The overall result has been shown in fig. 1.
Table 2: Socio-demographic status of volunteers
Parameter Experimental and control volunteers (n =30)
n % Mean ± SDs
Education
Illiterate
Secondary
Higher secondary
Graduate and above
2
3
2
23
6.66
10
6.66
76.66
Occupation
Student
Service
Small business
Unemployed
14
13
1
2
46.66
43.33
3.33
6.66
Age in years
25 – 30
31 – 35
36 – 40
41 – 45
27
1
1
1
90
3.33
3.33
3.33
27.4500 ± 3.37932
Smoking behavior
Non smoker
Partial smoker
Habituate
14
3
13
46.66
10
43.33
Marital Status
Married
Unmarried
Divorced
12
18
0
40
60
0

Effect of Tamarindus indica fruits on blood pressure
Pak. J. Pharm. Sci., 2006, Vol.19(2), 125-129
128
DISCUSSION
The data generated in this study indicates that, fruits of T.
indica has a diversified effect on total lipid profile. It was
found to impart a significant impact in lowering total
cholesterol level and LDL-cholesterol level in body without
altering the level of HDL-cholesterol. LDL-cholesterol
which is also known as ‘bad cholesterol’ is taken up by the
cells via LDL-receptors. LDL-receptor is a transmembrane
glycoprotein that recognizes apoB-100, the exclusive
apoprotein of LDLs and takes up LDL molecules through
receptor mediated endocytosis. The endocytosed membrane
vesicles fuse with lysosomes and, in which the apoproteins
are degraded and the cholesterol esters are hydrolyzed to
yield free cholesterol. The cholesterol is then incorporated
into plasma membrane as necessary. Since tamarind reduced
the total cholesterol level, there is probably a decrease in
intracellular cholesterol, and it is known that a decrease in
intracellular cholesterol level causes an upregulation of
LDL-receptor. Pulverized pulp of T. indica was also found
to reduce the diastolic blood pressure though it had no effect
either on systolic blood pressure or body weight. The
regulation of blood pressure in humans is a complex
interplay between several exogenous and endogenous
factors such as renin-angiotensin system or endothelin
system. The experiment, though confirms the potentiality of
T. indica fruits on lowering cholesterol and LDL-cholesterol
level, however further investigation is required on larger
population to quantify and qualify this issue. Although no
group did this particular work to see the effect of fruits of T.
indica on total lipid profile, similar type of work has been
reported using other plants. It has been reported that long-
term consumption of foods containing psyllium seed husk
has effect on serum lipids in subjects with
hypercholesterolemia (Davidson et al., 1998). Psyllium-
enriched cereals also lower blood total cholesterol and LDL
cholesterol, but not HDL cholesterol, in hyper-
cholesterolemic adults (Olson et al., 1997). Similarly, it has
been reported that supplementation with a pine bark extract
rich in polyphenols increases plasma antioxidant capacity
and alters the plasma lipoprotein profile (Devaraj,
2002).Our findings definitely reveals a new dimension on
the effect of fruits of T. indica, but further study is required
in larger population to quantify and qualify this issue.
ACKNOWLEDGEMENT
The authors express their gratefulness to BCSIR,
Bangladesh for funding this project.
REFERENCES
Anderson JW, Davidson MH and Blonde L (2000). Long
term cholesterol-lowering effects as an adjunct to diet
therapy in the treatment of hypercholesterolemia. Am. J.
Clin. Nutr., 71: 1433.
Anderson JW, Johnstone BM and Cook-Newell ME (1995).
Meta-analysis of the effects of soy protein on serum
lipids. N. Engl. J. Med., 332: 276.
Castano G, Mas R, Fernandez JC, Illnait J, Fernandez L
and Alvarez E (2001). Effect of policasanol in older
patients with type II hepercholesterolemia and high
coronary risk. J. Gerontol. A. Biol. Sci. Med. Sci., 56:
186.
Cotran KC (1999). Cellular Pathology. Robbins Pathologic
basis of disease, Fifth Edition, Elsvier, UK, p.40.
Davidson MH, Maki KC, Kong JC, Dugan LD, Torri SA,
Hall HA, Drennan KB, Anderson SM, Fulgoni VL,
Saldanha LG and Olson BH (1998). Long-term effects of
consuming foods containing psyllium seed husk on serum
lipids in subjects with hypercholesterolemia. Am. J. Clin.
Nutr., 67(3): 367-76.
Debourdeau PM, Djezzar S and Estival JL (2001). Life-
threatening cosinophlic pleuropericardial effusion related
to vitamin B5 and h. Ann. Pharmacother., 35: 424.
Delaney B, Nicolosi RJ, Wilson TA, Carlson T, Frazer S,
Zheng GH, Hess R., Ostergren K, Haworth J and
Knutson N (2003). Beta-glucan fractions from barley and
oats are similarly antiatherogenic effect of Allim sativum.
J. Nutr., 133: 468.
Devaraj S, Vega-Lopez S, Kaul N, Schonlau F, Rohdewald
P and Jialal I (2002). Supplementation with a pine bark
extract rich in polyphenols increases plasma antioxidant
capacity and alters the plasma lipoprotein profile. Lipids,
37(10): 931-4.
Koscielny J, Klussendorf D and Latza R (1999). The
antiatherosclerotic effect of Allium sativum. Athero-
sclerosis, 144: 237.
Lopes-Virella MF, Stone P, Ellis S and Colwell JA (1977).
Cholesterol determination in high-density lipoproteins
separated by three different methods. Clin. Chem., 23:
882-884.
Nagele U, Hagele EO, Sauer G, Wiedemann E, Lehmann P,
Aahlefeld AW and Gruber WJ (1984). Reagent for the
enzymatic determination of serum total triglycerides with
improved lipolytic efficiency. J. Clin. Chem. Clin.
Biochem., 22: 165-174.
Olson BH, Anderson SM, Becker MP, Anderson JW,
Hunninghake DB, Jenkins DJ, LaRosa JC, Rippe JM,
Roberts DC, Stoy DB, Summerbell CD, Truswell AS,
Wolever TM, Morris DH and Fulgoni VL 3rd (1997).
Psyllium-enriched cereals lower blood total cholesterol
and LDL cholesterol, but not HDL cholesterol, in
hypercholesterolemic adults: results of a meta-analysis. J.
Nutr., 127(10): 1973-80.
Quiles JL, Mesa MD, Ramirez-Tortosa CL, Aguilera CM,
Battino M, Gil A and Ramirez-Tortosa MC (2002).
Curcuma longa extract supplemenatation reduces
oxidative stress and attenuates aortic fatty streak
development in rabbits. Arterioscler Thromb. Vasc Biol.,
22: 1225.

A.S.M. Maruf Iftekhar et al.
Pak. J. Pharm. Sci., 2006, Vol.19(2), 125-129
129
Richmond W (1973). Preparation and properties of a
cholesterol oxidase from Nocradia sp. and its application
to the enzymatic assay to total cholesterol in serum. Clin.
Chem., 18: 1350.
Roeschlau P, Bernt E and Gruber W (1974). Enzymatic
determination of total cholesterol in serum. J. Clin.
Chem. Clin. Biochem., 12: 227.
Ros E, Nunez I, Perez-Heras A, Serra M, Gilabert R, Casals
E and Deulofeu RA (2004). Walnut Diet Improves
Endothelial Function in Hypercholesterolemic Subjects:
A Randomized Crossover Trail. Circulation, 109: 1609.
INTRODUCTION
Liver diseases such as jaundice, cirrhosis and fatty liver are
very common worldwide. There are many factors for the
development of these diseases, one of the important factors
being the use of drugs. Boswellia serrata (Burseraceae),
occurs in tropical parts of Asia and Africa (Kokate, 1998).
The oleo-gum-resin of the plant is known to possess a
variety of activities such as antiarthritic, antiinflammatory,
antitumour
and anticarcinogenic effect (Singh and Atal,
1986; Huang et al., 2000). This plant is widely used for its
antiinflammatory activity, which is mediated by its active
constituents, boswellic acids. Studies have also been carried
out to determine the toxicity of this plant. It is reported that
Boswellia serrata applied topically can produce allergic
contact dermatitis (Acebo et al., 2004). The hexane extract
of the oleo-gum-resin of this plant, which is rich in
Trinder P (1969). Determination of glucose in blood using
oxidase with an alternative glucose acceptor. Ann. Clin.
Biochem., 6: 24-27.
Yusuf M, Chowdhury J and Wahab MA (1994). Medicinal
Plants of Bangladesh, First Edition, BCSIR Laboratories,
Bangladesh, p.238.
Wieland H and Seidel DA (1999). A simple specific
method for precipitation of low density lipoproteins. J.
Lipid Res., 24: 904.
Received: 10-3-2006 – Accepted: 26-4-2006
boswellic acids, is reported to produce hepatotoxicity in
large doses (1% in the diet) and it is also suggested that the
hexane extract of the plant should not be administered to
patients or volunteers participating in the clinical studies
without informing them about hepatotoxic nature of the
plant (Kiela et al., 2005). On the contrary, Pandey et al
(2005) reported that the alcoholic extract of oleo-gum-resin
of Boswellia serrata possess hepatoprotective activity that
may be due to presence of acetyl-α-boswellic acid. The
present study was undertaken to evaluate the effect of
hexane extract of oleo-gum-resin of Boswellia serrata,
widely used for its antiinflammatory activity on
experimental liver injury in rats.
MATERIALS AND METHODS
Experimental animals
Albino Wistar rats weighing 175-250 g of either sex were
used. Institutional Animal Ethics Committee approved the
ORIGINAL ARTICLE
EFFECT OF HEXANE EXTRACT OF BOSWELLIA SERRATA OLEO-GUM RESIN
ON CHEMICALLY INDUCED LIVER DAMAGE
JYOTHI Y, JAGADISH V KAMATH AND MOHAMMED ASAD*
Krupanidhi College of Pharmacy, # 5, Sarjapur Road, Koramangala, Bangalore-560 034, India
ABSTRACT
The hexane extract of oleo-gum-resin of Boswellia serrata (BSHE) was evaluated for its effect on liver injury
induced by carbon tetrachloride, paracetamol or thioacetamide. The BSHE was given in two different doses (87.5
mg/kg p.o. and 175mg/kg p.o.). Silymarin, a known hepatoprotective agent was used as standard. The lower dose of
BSHE (87.5mg/kg p.o.) significantly reduced the elevated levels of serum marker enzymes and prevented the
increase in liver weight in all three models of liver injury, while the higher dose showed mild hepatoprotective
activity. The hepatoprotective effect of lower dose of BSHE was supported by changes in histopathology. It was
concluded that hexane extract of oleo-gum-resin of Boswellia serrata plant in lower doses possess hepatoprotective
activity.
Keywords: Boswellia serrata, hepatoprotective, carbon tetrachloride, paracetamol, thioacetamide.
*Corresponding author: e-mail: mohammedasad@rediffmail.com